A: Off-Shore Discharge Tunnel Outfall

U.S. Environmental Protection Agency · from the EPA · 119 pages · 4.0 MB
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Attachment A
Off-Shore Discharge Tunnel Outfall
NPDES Permit No. MA0103284
Boston, MA 
Discharge
Serial Number 
Discharge Location Receiving Water 
TO1 Between latitude 42 o 23'03.2",
longitude 70 o 48'13.5" and latitude
42 o 23'19.6", longitude 70 o 46'48.4" 
Massachusetts Bay

Attachment B 
Combined Sewer Overflow Discharge Outfalls 
NPDES Permit No. MA0103284 
Boston, MA 
Discharge Serial Discharge Name (By Location) Receiving Water
Number * 
003 Cambridge Park Drive Overflow Alewife Brook
201 Cottage Farm Chlorination and Detention Station Charles River
203 Prison Point CSO Treatment Facility Inner Harbor
205 Somerville Marginal CSO Pretreatment Facility Mystic River
010 Brookline St. Overflow Charles River
018 Gloucester St. Overflow Charles River
019 Exeter St. Overflow Charles River
020 Berkely St. Overflow Charles River
021 Mt. Vernon St. Overflow Charles River
022 Cambridge St. Overflow Charles River
023 Fens Gatehouse Overflow Charles River
205A Somerville Marginal/ Fellsway by Wellington Bridge Mystic River
207 Constitution Beach Boston Harbor
209 Fox Point via BOS088/089 Dorchester Bay
211 Commercial Point via BOS090 Dorchester Bay 
The CSO outfall 205A is used by the MWRA and the City of Somerville. The MWRA's designated sampling point
for outfalls 205 and 205A shall be at the following location: 
(1) Somerville Marginal (205) and Sommerville/Fellsway (205A) - 42 " 23' 0.608" N Latitude and 71 " 05' 0.062"
Longitude 
The CSO outfalls 211 and 209 are used by the MWRA and the Boston Water and Sewer Commission. The MWRA's
designated sampling points shall be at the following locations: 
(1) Commercial Point (211) - 42 " 17' 0.862" N Latitude and 71 " 03' 0.240" Longitude 
(2) Fox Point (209) - 42 " 18' 0.278" N Latitude and 71 " 03' 0.261" W Longitude

Attachment C
Flow Schematic
NPDES Permit No. MA0Q103284

Boston, MA
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(Graphic reprinted courtesy of the Boston Globe)

Attachment D 
Communities within the MWRA Conveyance System 
NPDES Permit No. MA0103284 
Boston, MA 
The following 60 communities are served by the MWRA water and/or wastewater conveyance systems: 
1. Water: 2. Sewer: 3. Water, Sewer 4. Water and Sewer: 
and/or Combined 
Peabody* Wilmington Storm Water: Stoneham Needham* 
Lynn** Burlington Woburn* Norwood 
Lynnfield Dedham Boston Winchester* Bedford* 
Saugus Natick Cambridge* Lexington Canton* 
Weston Ashland Chelsea Waltham Winthrop 
Marlborough* Westwood Somerville Arlington Quincy 
Southborough Walpole Belmont Milton 
Northborough* Stoughton Medford Newton 
Worcester*** Randolph Malden Watertown 
Chicopee Braintree Everett Framingham 
Clinton Holbrook Revere Melrose 
Leominster* Weymouth Wellesley* Brookline 
Nahant North District of Hingham Wakefield* 
Wilbraham Reading 
Swampscott 
South Hadley Fire District #1 
Marblehead 
* - is partially supplied water by MWRA.
** - water supplied to GE only.
*** - MWRA is emergency back-up water supply. 
Wastewater, and combined (i.e., sewage and storm water) wastewater, are transported through 230 miles of MWRA
pipes to the treatment system at Deer Island in Boston, MA. The MWRA provides water and/or sewer services to
60 communities.

Attachment E 
Marine Acute Toxicity Test Procedure and Protocol 
I. GENERAL REQUIREMENTS 
The permittee shall conduct acceptable acute toxicity tests in accordance with the appropriate test protocols
described below: 
! ! Mysid Shrimp ( Mysidopsis bahia ) definitive 48 hour test. 
! ! Inland Silverside ( Menidia beryllina ) definitive 48 hour test. 
Acute toxicity data shall be reported as outlined in Section VIII. 
II. METHODS 
Methods to follow are those recommended by EPA in: 
Weber, C.I. et al. Methods for Measuring the Acute Toxicity of Effluents to Freshwater and Marine Organisms , 
Fourth Edition. Environmental Monitoring Systems Laboratory, U.S. Environmental Protection Agency, Cincinnati, 
OH. August 1993, EPA/600/4-90/027F. 
Any exceptions are stated herein. 
III. SAMPLE COLLECTION 
A discharge sample shall be collected. Aliquots shall be split from the sample, containerized and preserved (as per
40 CFR Part 136) for the chemical and physical analyses. The remaining sample shall be dechlorinated (if detected) in
the laboratory using sodium thiosulfate for subsequent toxicity testing. ( Note that EPA approved test methods
require that samples collected for metals analyses be preserved immediately after collection. ) Grab samples must be
used for pH, temperature, and total residual oxidants (as per 40 CFR Part 122.21). 
Standard Methods for the Examination of Water and Wastewater describes dechlorination of samples (APHA, 1992).
Dechlorination can be achieved using a ratio of 6.7 mg/L anhydrous sodium thiosulfate to reduce 1.0 mg/L chlorine.
A thiosulfate control (maximum amount of thiosulfate in lab control or receiving water) should also be run. 
All samples held overnight shall be refrigerated at 4 o C. 
IV. DILUTION WATER 
A grab sample of dilution water used for acute toxicity testing shall be collected at a point away from the discharge
which is free from toxicity or other sources of contamination. Avoid collecting near areas of obvious road or
agricultural runoff, storm sewers or other point source discharges. An additional control (0% effluent) of a standard
laboratory water of known quality shall also be tested. 
If the receiving water diluent is found to be, or suspected to be toxic or unreliable, an alternate standard dilution
water of known quality with a conductivity, salinity, total suspended solids, and pH similar to that of the receiving
water may be substituted AFTER RECEIVING WRITTEN APPROVAL FROM THE PERMIT ISSUING
AGENCY(S) . Written requests for use of an alternative dilution water should be mailed with supporting
documentation to the following address: 
Director 
Office of Ecosystem Protection 
U.S. Environmental Protection Agency-New England

_________________________________________________________________ 
JFK Federal Building (CAA) 
Boston, MA 02203 
It may prove beneficial to have the proposed dilution water source screened for suitability prior to toxicity testing.
EPA strongly urges that screening be done prior to set up of a full definitive toxicity test any time there is question
about the dilution water's ability to support acceptable performance as outlined in the 'test acceptability' section of
the protocol. 
V. TEST CONDITIONS AND TEST ACCEPTABILITY CRITERIA 
EPA New England requires tests be performed using four replicates of each control and effluent concentration
because the non-parametric statistical tests cannot be used with data from fewer replicates. The following tables
summarize the accepted Mysid and Menidia toxicity test conditions and test acceptability criteria: 
EPA NEW ENGLAND RECOMMENDED EFFLUENT TOXICITY TEST CONDITIONS FOR THE MYSID, 
MYSIDOPSIS BAHIA 48 HOUR TEST 1 
1. Test type Static, non-renewal 
2. Salinity 25ppt + 10 percent for all dilutions by adding dry ocean salts 
3. Temperature ( o C) 20 o C + 1 o C or 25 o C + 1 o C 
4. Light quality Ambient laboratory illumination 
5. Photoperiod 16 hour light, 8 hour dark 
6. Test chamber size 250 ml 
7. Test solution volume 200 ml 
8. Age of test organisms 1-5 days 
9. No. Mysids per test chamber 10 
10. No. of replicate test chambers per treatment 4 
11. Total no. Mysids per test concentration 40 
12. Feeding regime Light feeding using concentrated Artemia nauplii while holding
prior to initiating the test 
13. Aeration 2 None 
14. Dilution water Natural seawater, or deionized water mixed with artificial sea
salts 
15. Dilution factor > 0.5 
16. Number of dilutions 3 5 plus a control. An additional dilution at the permitted effluent
concentration (% effluent) is required if it is not included in the
dilution series. 
17. Effect measured Mortality - no movement of body appendages on gentle
prodding

_________________________________________________________________ 
_________________________________________________________________ 
18. Test acceptability 90% or greater survival of test organisms in control solution 
19. Sampling requirements For on-site tests, samples are used within 24 hours of the time
that they are removed from the sampling device. For off-site
tests, samples must be first used within 36 hours of collection. 
20. Sample volume required Minimum 1 liter for effluents and 2 liters for receiving waters 
Footnotes: 
1. Adapted from EPA/600/4-90/027F. 
2. If dissolved oxygen falls below 4.0 mg/L, aerate at rate of less than 100 bubbles/min. Routine D.O. checks are
recommended. 
3. When receiving water is used for dilution, an additional control made up of standard laboratory dilution water
(0% effluent) is required. 
EPA NEW ENGLAND RECOMMENDED TOXICITY TEST CONDITIONS FOR THE INLAND SILVERSIDE, 
MENIDIA BERYLLINA 48 HOUR TEST 1 
1. Test Type Static, non-renewal 
2. Salinity 25 ppt + 2 ppt by adding dry ocean salts 
3. Temperature 20 o C + 1 o C or 25 o C + 1 o C 
4. Light Quality Ambient laboratory illumination 
5. Photoperiod 16 hr light, 8 hr dark 
6. Size of test vessel 250 mL (minimum) 
7. Volume of test solution 200 mL/replicate (minimum) 
8. Age of fish 9-14 days; 24 hr age range 
9. No. fish per chamber 10 (not to exceed loading limits) 
10. No. of replicate test vessels per
treatment 
4 
11. total no. organisms per
concentration 
40 
12. Feeding regime Light feeding using concentrated Artemia nauplii while holding prior to
initiating the test 
13. Aeration 2 None 
14. Dilution water Natural seawater, or deionized water mixed with artificial sea salts. 
3

_________________________________________________________________ 
15. Dilution factor > 0.5 
16. Number of dilutions 3 5 plus a control. An additional dilution at the permitted concentration
(% effluent) is required if it is not included in the dilution series. 
17. Effect measured Mortality-no movement on gentle prodding. 
18. Test acceptability 90% or greater survival of test organisms in control solution. 
19. Sampling requirements For on-site tests, samples must be used within 24 hours of the time they
are removed from the sampling device. Off-site test samples must be
used within 36 hours of collection. 
20. Sample volume required Minimum 1 liter for effluents and 2 liters for receiving waters. 
Footnotes : 
1. Adapted from EPA/600/4-90/027F. 
2. If dissolved oxygen falls below 4.0 mg/L, aerate at rate of less than 100 bubbles/min. Routine D.O. checks
recommended. 
3. When receiving water is used for dilution, an additional control made up of standard laboratory dilution water
(0% effluent) is required. 
VI. CHEMICAL ANALYSIS 
At the beginning of the static acute test, pH, specific conductance, salinity, total residual oxidants, and temperature
must be measured at the beginning and end of each 24 hour period in each dilution and in the controls. The
following chemical analyses shall be performed for each sampling event. 
Parameter Minimum Quantification 
Effluent Diluent Level (mg/L) 
pH x x --
Specific Conductance x x --
Salinity x x PT(o/oo) 
Total Residual Oxidants *1 x x 0.05 
Total Solids and Suspended Solids x x --
Ammonia x x 0.1 
Total Organic Carbon x x 0.5 
Total Metals 
Cd x 0.001 
Cr x 0.005 
4

Pb x x 0.005 
Cu x x 0.0025 
Zn x x 0.0025 
Ni x x 0.004 
A l x x 0.02 
Superscript : 
*1 Total Residual Oxidants 
Either of the following methods from the 18th Edition of the APHA Standard Methods for the Examination 
of Water and Wastewater must be used for these analyses: 
-Method 4500-Cl E Low Level Amperometric Titration (the preferred method); 
-Method 4500-CL G DPD Photometric Method. 
or use USEPA Manual of Methods Analysis of Water or Wastes , Method 330.5. 
VII. TOXICITY TEST DATA ANALYSIS 
LC50 Median Lethal Concentration 
An estimate of the concentration of effluent or toxicant that is lethal to 50% of the test organisms during the time
prescribed by the test method. 
Methods of Estimation: 
! Probit Method 
! Spearman-Karber 
! Trimmed Spearman-Karber 
! Graphical 
See flow chart in Figure 6 on page 77 of EPA 600/4-90/027F for appropriate method to use on a given data set. 
No Observed Acute Effect Level (NOAEL) 
See flow chart in Figure 13 on page 94 of EPA 600/4-90/027F. 
VIII. TOXICITY TEST REPORTING 
The following must be reported: 
! Description of sample collection procedures, site description; 
! Names of individuals collecting and transporting samples, times and dates of sample collection and analysis 
on chain-of-custody; and 
5

! General description of tests: age of test organisms, origin, dates and results of standard toxicant tests; light
and temperature regime; other information on test conditions if different than procedures recommended.
Reference toxicity test data must be included. 
! Raw data and bench sheets. 
! All chemical/physical data generated. (Include minimum detection levels and minimum quantification
levels.) 
! Provide a description of dechlorination procedures (as applicable). 
! Any other observations or test conditions affecting test outcome. 
! Statistical tests used to calculate endpoints. 
6

Attachment F 
Marine Chronic Toxicity Test Procedure and Protocol 
I. GENERAL REQUIREMENTS 
The permittee shall conduct acceptable silverside chronic (and modified acute) and sea urchin chronic toxicity tests
in accordance with the appropriate test protocols described below: 
! ! Inland Silverside ( Menidia beryllina ) Larval Growth and Survival Test. 
! ! Sea Urchin ( Arbacia punctulata ) 1 Hour Fertilization Test. 
Chronic and acute toxicity data shall be reported as outlined in Section VIII. The chronic Menidia test can be used
to calculate an LC50 at the end of 48 hours of exposure when both an acute (LC50) and a chronic (C-NOEC) test is
specified in the permit. 
II. METHODS 
Methods to follow are those recommended by EPA in: 
Klemm, D.J. et al. Short Term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters To
Marine and Estuarine Organisms , Second Edition. Environmental Monitoring Systems Laboratory, U.S.
Environmental Protection Agency, July 1994, EPA/600/4-91/003. 
Any exceptions are stated herein. 
III. SAMPLE COLLECTION 
For each sampling event involving the Menidia beryllina , three discharge samples shall be collected. Fresh samples
are necessary for Days 1, 3, and 5 (see Section V. for holding times). A single sample is necessary for the Arbacia
punctulata test. The sample shall be analyzed chemically (see Section VI). The initial sample (Day 1) is used to start
the tests, and for test solution renewal on Day 2. The second sample is collected for use at the start of Day 3, and
for renewal on Day 4. The third sample is used on Days 5, 6, and 7. The initial (Day 1) sample will be analyzed
chemically (see Section VI). Day 3 and 5 renewal samples will be held until test completion. If either the Day 3 or 5
renewal sample is of sufficient potency to cause lethality to 50 percent or more test organisms in any of the dilutions
for either species, then a chemical analysis shall be performed on the appropriate sample(s) as well. 
Aliquots shall be split from the sample, containerized and preserved (as per 40 CFR Part 136) for the chemical and
physical analyses. The remaining sample shall be dechlorinated (if detected) in the laboratory using sodium
thiosulfate for subsequent toxicity testing. ( Note that EPA approved test methods require that samples collected for
metals analyses be preserved immediately after collection. ) Grab samples must be used for pH, temperature, and total
residual oxidants (as per 40 CFR Part 122.21). 
Standard Methods for the Examination of Water and Wastewater describes dechlorination of samples (APHA, 1992).
Dechlorination can be achieved using a ratio of 6.7 mg/L anhydrous sodium thiosulfate to reduce 1 mg/L chlorine. A
thiosulfate control (maximum amount of thiosulfate in lab control or receiving water) should also be run. 
All samples held overnight shall be refrigerated at 4 o C. 
IV. DILUTION WATER 
Grab samples of receiving water used for chronic toxicity testing shall be collected from one or several distances
away from the discharge. It may be necessary to test receiving water at several distances in a separate chronic test

__________________________________________________________________ 
to determine the extent of the zone of toxicity. Avoid collecting near areas of obvious road or agricultural runoff,
storm sewers or other point source discharges. An additional control (0% effluent) of a standard laboratory water of
known quality shall also be tested. 
If the receiving water diluent is found to be, or suspected to be toxic or unreliable, an alternate standard dilution
water of known quality with a conductivity, salinity, total suspended solids, organic carbon, and pH similar to that of
the receiving water may be substituted AFTER RECEIVING WRITTEN APPROVAL FROM THE PERMIT
ISSUING AGENCY(S) . Written requests for use of an alternative dilution water should be mailed with supporting
documentation to the following address: 
Director 
Office of Ecosystem Protection 
U. S. Environmental Protection Agency-New England 
JFK Federal Building (CAA) 
Boston, MA 02203 
It may prove beneficial to the permittee to have the proposed dilution water source screened for suitability prior to
toxicity testing. EPA strongly urges that screening be done prior to set up of a full definitive toxicity test any time
there is question about the dilution water's ability to support acceptable
performance as outlined in the 'test acceptability' section of the protocol. 
V. TEST CONDITIONS AND TEST ACCEPTABILITY CRITERIA 
EPA New England requires that tests be performed using four replicates of each control and effluent concentration
because the on-parametric statistical tests cannot be used with data from fewer replicates. Also, if a reference
toxicant test was being performed concurrently with an effluent or receiving water test and fails, both tests must be
repeated. 
The following tables summarize the accepted Menidia and Arbacia toxicity test conditions and test acceptability
criteria: 
EPA NEW ENGLAND RECOMMENDED TEST CONDITIONS FOR THE SEA URCHIN, ARBACIA PUNCTULATA ,
FERTILIZATION TEST 1 
1. Test type Static, non-renewal 
2. Salinity 30 o/oo + 2 o/oo by adding dry ocean salts 
3. Temperature 20 + 1 o C 
4. Light quality Ambient laboratory light during test preparation 
5. Light intensity 10-20 uE/m 2 /s, or 50-100 ft-c (Ambient Laboratory Levels) 
6. Test vessel size Disposal (glass) liquid scintillation vials (20 ml capacity), presoaked in 
control water 
7. Test solution volume 5 ml 
8. Number of sea urchins Pooled sperm from four males and pooled eggs from four females are used 
per test 
9. Number of egg and sperm cells About 2000 eggs and 5,000,000 sperm cells per vial
per chamber

_________________________________________________________________ 
______________________________________________________________ 
10. Number of replicate chambers 4 
per treatment 
11. Dilution water Uncontaminated source of natural seawater or deionized water mixed with 
artificial sea salts 
12. Dilution factor Approximately 0.5 
13. Test duration 1 hour and 20 minutes 
14. Effects measured Fertilization of sea urchin eggs 
15. Number of treatments per test 2 5 and a control. An additional dilution at the permitted effluent 
concentration (% effluent) is required. 
16. Acceptability of test Minimum of 70% fertilization in controls. Effluent concentrations exhibiting 
greater than 70% fertilization, flagged as statistically significantly different 
from the controls, will not be considered statistically different from the 
controls for NOEC reporting. 
17. Sampling requirements For on-site tests, samples are to be used within 24 hours of the time that
they are removed from the sampling device. For off-site tests, samples must
be first used within 36 hours of collection. 
18. Sample volume required Minimum 1 liter 
Footnotes: 
1. Adapted from EPA/600/4-91/003, July 1994. 
2. When receiving water is used for dilution, an additional control made up of standard laboratory dilution water
(0% effluent) is required. 
EPA NEW ENGLAND RECOMMENDED TEST CONDITIONS FOR THE INLAND SILVERSIDE, MENIDIA
BERYLLINA , GROWTH AND SURVIVAL TEST 1 
1. Test type Static, renewal 
2. Salinity 5 o/oo to 32 o/oo + 2 o/oo by adding artificial sea salts 
3. Temperature 25 + 1 o C 
4. Light quality Ambient laboratory light 
5. Light intensity 10-20 uE/m 2 /s, or 50-100 ft-C 
(Ambient Laboratory Levels) 
6. Photoperiod 16 hr light, 8 hr darkness 
3

_________________________________________________________________ 
7. Test vessel size 600 - 1000 mL beakers or equivalent (glass test chambers should be 
used) 
8. Test solution volume 500-750 mL/replicate loading and DO restrictions must be met 
9. Renewal of test solutions Daily using most recently collected sample. 
10. Age of test organisms Seven to eleven days post hatch; 24 hr range in age. 
11. Larvae/test chamber 15 (minimum of 10) 
12. Number of replicate chambers 4 per treatment 
13. Source of food Newly hatched and rinsed Artemia nauplii less than 24 hr old 
14. Feeding regime Feed once a day 0.10 g wet wt Artemia nauplii per replicate on days 0
2; feed 0.15 g wet wt Artemia nauplii per replicate on days 3-6 
15. Cleaning Siphon daily, immediately before test solution renewal and feeding 
16. Aeration 2 None 
17. Dilution water Uncontaminated source of natural seawater; or deionized water mixed
with artificial sea salts. 
18. Effluent concentrations 3 5 and a control. An additional dilution at the permitted effluent 
concentration (% effluent) is required. 
19. Dilution factor > 0.5 
20. Test duration 7 days 
21. Effects measured Survival and growth (weight) 
22. Acceptability of test The average survival of control larvae is a minimum of 80%, and the
average dry wt of unpreserved control larvae is a minimum of 0.5 mg,
or the average dry wt of preserved control larvae is a minimum of 0.43
mg if preserved not more than 7 days in 4% formalin or 70% ethanol. 
23. Sampling requirements For on-site tests, samples are collected daily and used within 24 hours
of the time they are removed from the sampling device. For off-site
tests, samples must be first used within 36 hours of collection. 
24. Sample Volume Required Minimum of 6 liters/day. 
Footnotes: 
1 Adapted from EPA/600/4-91/003, July 1994. 
2 If dissolved oxygen (D.O.) falls below 4.0 mg/L, aerate all chambers at a rate of less than 100 bubbles/min.
Routine D.O. checks are recommended. 
3 When receiving water is used for dilution, an additional control made up of standard laboratory dilution water
(0% effluent) is required. 
VI. CHEMICAL ANALYSIS 
4

As part of each daily renewal of the Menidia test, pH, dissolved oxygen, specific conductance, total residual oxidants,
and temperature must be measured at the beginning and end of each 24 hour period in each dilution and in the controls.
It must also be done at the start of the Arbacia test. The following chemical analyses shall be performed for each
sampling event. 
Parameter Minimum 
Quantification 
Effluent Diluent Level(mg/L) 
pH x x -- 
Specific Conductance x x -- 
Salinity x x PPT(o/oo) 
Total Residual Oxidants *1 x x 0.05 
Total Solids and Suspended Solids x x -- 
Ammonia x x 0.1 
Total Organic Carbon x x 0.5 
Total Metals 
Cd x 0.001 
Cr x 0.005 
Pb x x 0.005 
Cu x x 0.0025 
Zn x x 0.0025 
Ni x x 0.004 
A l x x 0.02 
Superscripts : 
*1 Total Residual Oxidants 
Either of the following methods from the 18th Edition of the APHA (1992) Standard Methods for the
Examination of Water and Wastewater must be used for these analyses: 
-Method 4500-CL E the Amperometric Titration Method (the preferred method);
-Method 4500-CL G the DPD Photometric Method. 
or use USEPA Manual of Methods Analysis of Water or Wastes , Method 330.5. 
VII. TOXICITY TEST DATA ANALYSIS 
LC50 Median Lethal Concentration (Determined at 48 Hours) 
Methods of Estimation: 
! Probit Method 
! Spearman-Karber 
! Trimmed Spearman-Karber 
5

! Graphical 
See flow chart on page 56 of EPA/600/4-91/003 for appropriate point estimation method to use on a given data set. 
Chronic No Observed Effect Concentration (C-NOEC) 
Methods of Estimation: 
! Dunnett's Procedure 
! Bonferroni's T-Test 
! Steel's Many-One Rank Test 
! Wilcoxin Rank Sum Test 
Reference flow charts on pages 191, 192, and 321 of EPA/600/4-91/003 for the appropriate method to u s e on a given data
set. 
In the case of two tested concentrations causing adverse effects but an intermediate concentration not causing a
statistically significant effect, report the C-NOEC as the lowest concentration where there is no observable effect. The
definition of NOEC in the EPA Technical Support Document only applies to linear dose-response data. 
VIII. TOXICITY TEST REPORTING 
A report of results will include the following: 
! Description of sample collection procedures, site description; 
! Names of individuals collecting and transporting samples, times and dates of sample collection and analysis 
on chain-of-custody; and 
! General description of tests:age of test organisms, origin, dates and results of standard toxicant tests; light and 
temperature regime; other information on test conditions if different than procedures recommended. Reference 
toxicant test data should be included. 
! All chemical/physical data generated. (Include minimum detection levels and minimum quantification levels.) 
! Raw data and bench sheets. 
! Provide a description of dechlorination procedures (as applicable). 
! Any other observations or test conditions affecting test outcome. 
(July 1, 1990) 6

Attachment G 
Industrial Pretreatment Program Annual Report 
NPDES Permit No. MA0103284 
Boston, MA 
The information described below shall be included in the pretreatment program annual reports: 
1. An updated list of all industrial users by category, as set forth in 40 CFR 403.8(f)(2)(i), indicating compliance
or noncompliance with the following: 
i. Baseline monitoring reporting requirements for newly promulgated industries, 
ii. Compliance status reporting requirements for newly promulgated industries, 
iii. Periodic (semi-annual) monitoring reporting requirements, 
iv. Categorical standards, and 
v. Local limits; 
2. A summary of compliance and enforcement activities during the preceding year, including the number of 
i. Significant industrial users inspected by POTW (include inspection dates for each industrial user), 
ii. Significant industrial users sampled by POTW (include sampling dates for each industrial user), 
iii. Compliance schedules issued (include list of subject users), 
iv. Written notices of violations issued (include list of subject users), 
v. Administrative orders issued (include list of subject users), 
vi. Criminal or civil suits filed (include list of subject users) and, 
vii. Penalties obtained (include list of subject users and penalty amounts); 
3. A list of significantly violating industries required to be published in a local newspaper in accordance with 40
CFR 403.8(f)(2)(vii); 
4. A narrative description of program effectiveness and present and proposed changes to the program, such as
funding, staffing, ordinances, regulations, rules and/or statutory authority; 
5. A summary of all pollutant analytical results for influent, effluent, sludge and any toxicity or bioassay data from
the wastewater treatment facility. The summary shall include a comparison of influent sampling results versus
threshold inhibitory concentrations for the MWRA wastewater treatment system and effluent sampling results
versus water quality standards. Such a comparison shall be based on the sampling program described in the
paragraph below or any similar sampling program described in this Permit. 
A t a minimum, annual sampling and analysis of the influent and effluent of the MWRA's Wastewater Plant shall
be conducted for the following pollutants: 
a.) Total Cadmium f.) Total Nickel 
b.) Total Chromium g.) Total Silver 
c.) Total Copper h.) Total Zinc 
d.) Total Lead i.) Total Cyanide 
e.) Total Mercury j.) Total Arsenic 
The sampling program shall consist of one 24-hour flow-proportioned composite and at least one grab sample
that is representative of the flows received by the POTW. The composite shall consist of hourly flow-
proportioned grab samples taken over a 24-hour period if the sample is collected manually or shall consist of
a minimum of 48 samples collected at 30 minute intervals if an automated sampler is used. Cyanide shall be
taken as a grab sample during the same period as the composite sample. Sampling and preservation shall be
consistent with 40 CFR Part 136.

6. A detailed description of all interference and pass-through that occurred during the past year; 
7. A thorough description of all investigations into interference and pass-through during the past year; 
8. A description of monitoring, sewer inspections and evaluations which were done during the past year to detect
interference and pass-through, specifying parameters and frequencies; 
9. A description of actions being taken to reduce the incidence of significant violations by significant industrial
users; and, 
10. The date of the latest adoption of local limits and an indication as to whether or not the Authority is under a
State or Federal compliance schedule that includes steps to be taken to revise local limits. 
11. Information on any new introduction of pollutants into MWRA’s sewer system from a user which would be
subject to section 301 or 306 of the Clean Water Act if it were directly discharging those pollutants and on any
substantial change in the volume or character of pollutants being introduced into MWRA’s sewer system by
a user. For purposes of this paragraph, adequate notice shall include information on the quality and quantity
of effluent introduced into MWRA’s sewer system and any anticipated impact of the change on the quantity
or quality of effluent to be discharged from MWRA’s treatment plant.

Attachment H 
Total Residual Chlorine 
Discharge Limit Calculation 
NPDES Permit No. MA0103284 
Boston, MA 
Water Quality Limitation Equation:
C L = C + [(C - C )/(1/S + 1/S b - 1/(S )(S b )] a c a n n 
Given:
C L = water quality limitation
C a = maximum ambient data sample
C c = marine water quality criterion
C c1 = 13 ug/l = Acute
C c2 = 7.5 ug/l = Chronic
S n = flux-average nearfield dilution
S b = farfield background build-up dilution
Q e1 = Maximum Daily Flow = 990 MGD
Q e2 = Average Monthly Flow = 690 MGD
I d = Initial Dilution
I d1 = 62.0:1 ratio, at 990 MGD, 1 part effluent to 62 parts receiving water
I d2 = 69.1:1 ratio, at 690 MGD, 1 part effluent to 69.1 parts receiving water
S n = Flux-Average Nearfield Dilution
S n1 = (62.0 x 1.15) = 71.3:1, at 990 MGD
S n2 = (69.1 x 1.15) = 79.5:1, at 690 MGD 
(Note: 1.15 = flux-average correction value for this diffuser outfall.) 
S b = Farfield Background Build-up Dilution for a conservative toxic pollutant 
S b1 = 150:1, acute 
S b2 = 256:1, chronic 
= 364:1, human health 
Sample Calculation:
C L = C + [(C - C )/(1/S + 1/S b - 1/(S )(S b )] a c a n n 
Acute:
C L = 0 + [(13 -0)/(1/71.3 + 1/150 - 1/(71.3)(150)]
C L = [(13)/(0.014025)+(0.006666)-(0.000093502)] 
C L = 631 ug/l = 0.631 mg/l 
Chronic:
C L = 0 + [(7.5 - 0)/(1/79.5 + 1/256 - 1/(79.5)(256)]
C L = [(7.5)/(0.012578)+(0.0039062)-(0.000049135)]
C L = 456 ug/l = 0.456 mg/l 
Therefore, the total residual chlorine limits for the tunnel outfall are: (1) maximum daily limit = 631 ug/l, and (2)
average monthly limit = 456 ug/l 
Footnotes : 
1. Effluent limits for daily maximum total residual chlorine are based on the chronic values defined in the EPA
Quality Criteria for Water, 1986 (Gold Book) as adopted into the State Water Quality Standards, multiplied
by the available receiving water dilution. 
2. Under Section 301(b)(1)(C) of the CWA, discharges are subject to effluent limitations based on Water

Quality Standards. The Massachusetts Surface Water Quality Standards include the requirements for the
regulation and control of toxic constituents and also require that EPA criteria established, pursuant to
Section 304(a) of the CWA, shall be used unless a site specific criteria is established. The state will limit or
prohibit discharges of pollutants to surface waters to assure that surface water quality standards of the
receiving waters are protected and maintained or attained.

Attachment I 
Sludge Applier's Responsibilities 
These conditions do not apply to material meeting conditions at 13 e and f of the permit. The person who applies
bulk sewage sludge shall comply with the following requirements: 
General Requirements: 
1. Bulk sewage sludge shall not be applied to the land except in accordance with 40 C.F.R. Part 503 Subpart B. 
2. Bulk sewage sludge shall not be applied if any of the cumulative pollutant loading rates in Paragraph 13. g. 
vii. have been reached on the site. 
3. The person who applies the bulk sewage sludge shall obtain notice and necessary information to comply
with the requirements of 40 C.F.R. Part 503 Subpart B. 
4. The person who applies the bulk sewage sludge shall obtain the following information: 
a. Prior to application of bulk sewage sludge, the person who proposes to apply the bulk sewage shall contact
the permitting authority for the state in which the bulk sewage sludge will be applied to determine whether
bulk sewage sludge subject to the cumulative pollutant loading rates in § 503.13(b)(2) has been applied to
the site since July 20, 1993. 
b. If bulk sewage sludge subject to the cumulative pollutant loading rates has not been applied to the site, the
cumulative amount for each pollutant listed in Paragraph 13. g. vii. may be applied. 
c. If bulk sewage sludge subject to the cumulative pollutant loading rates has been applied to the site since
July 20, 1993, and the cumulative amount of each pollutant applied to the site since that date is known, the
cumulative amount of each pollutant applied to the site shall be used to determine the additional amount of
each pollutant that can be applied to the site such that the loading rates in Paragraph 13. g. vii. are not
exceeded. 
d. If bulk sewage sludge subject to the cumulative pollutant loading rates has been applied to the site since
July 20, 1993, and the cumulative amount of each pollutant applied to the site since that date is not known,
an additional amount of any pollutant may not be applied to the site. 
5. The person who applies the bulk sewage sludge shall provide the owner or lease holder of the land on 
which the bulk sewage sludge is applied notice and necessary information to comply with the requirements
of 40 C.F.R. Part 503 Subpart B. 
6. The person who applies the bulk sewage sludge shall provide written notice, prior to the initial application
of the bulk sewage sludge, to the permitting authority for the State in which the bulk sewage sludge will be
applied. The notice shall include: 
a. The location, by either street address or latitude and longitude, of the land application site. 
b. The name, address, telephone number, and National Pollutant Discharge Elimination System permit number
(if appropriate) of the person who will apply the bulk sewage sludge. 
Management Practices: 
l. The person who applies the bulk sewage sludge to the land shall comply with the following management
practices:

a. The bulk sewage sludge shall not be applied to the land if it is likely to adversely affect a threatened or 
endangered species listed under section 4 of the Endangered Species Act, or its designated habitat. 
b. The bulk sewage sludge shall not be applied to agricultural land, forest land, a public contact site or a land
reclamation site that is frozen, snow-covered, or flooded so that the bulk sewage sludge enters a wetland or
other water of the United States as defined in 40 C.F.R. § 122.2, except as provided in a permit issued
pursuant to section 402 or 404 of the Clean Water Act. 
c. Bulk sewage sludge shall not be applied to agricultural land, forest land, a public contact site, or a land
reclamation site that is less than 10 meters (33 feet) from waters of the United States, as defined in 40 C.F.R.
§ 122.2. 
d. The whole sludge application rate shall be applied at an agronomic rate designed to (i) provide the amount
of nitrogen needed by the crop or vegetation grown on the land; and (ii) minimize the amount of nitrogen
that passes below the root zone for the crop or vegetation grown of the land into the groundwater. 
Site Restrictions: 
When Class B pathogen requirements are met, the person who applies the bulk sewage sludge shall insure that the
following site restrictions are met for each site on which the bulk sewage sludge is applied: 
1. Food crops with harvested parts that touch the sewage sludge/soil mixture and are not totally above the
land surface shall not be harvested for 14 months after application of sewage sludge. 
2. Food crops with harvested parts below the surface of the land shall not be harvested for 20 months after
application of sewage sludge when the sewage sludge remains on the land surface for four months or
longer prior to incorporation into the soil. 
3. Food crops with harvested parts below the surface of the land shall not be harvested for 38 months after
application of sewage sludge when the sewage sludge remains on the land surface for less than four
months prior to incorporation into the soil. 
4. Food crops, feed crops, and fiber crops shall not be harvested for 30 days after application of sewage
sludge. 
5. Animals shall not be allowed to graze on the land for 30 days after application of sewage sludge. 
6. Turf grown on land where sewage sludge is applied shall not be harvested for one year after application of
the sewage sludge when the harvested turf is placed on either land with a high potential for public exposure
or a lawn. 
7. Public access to land with a high potential for public exposure shall be restricted for one year after
application of sewage sludge. 
8. Public access to land with a low potential for public exposure shall be restricted for 30 days after application
of sewage sludge. 
Record keeping requirements: 
1. The person who applies the bulk sewage sludge subject to the cumulative loading rate shall develop and
retain the following information indefinitely: 
a. The location, by either street address of latitude and longitude, of each site on which bulk sewage sludge is

applied. 
b. The number of hectares in each site on which bulk sewage sludge is applied. 
c. The date and time bulk sewage sludge is applied to each site. 
d. The cumulative amount of each pollutant listed in Paragraph 4a in the bulk sewage sludge applied to each
site, including the amount in Paragraph 4 of the General Requirements portion of this section. (in kilograms) 
e. The amount of sewage sludge applied to each site (in metric tons). 
f. The following certification statement: 
"I certify, under penalty of law, that the requirements to obtain information in § 503.12(e)(2) have been met
for each site on which bulk sewage sludge is applied. This determination has been made under my direction
and supervision in accordance with the system designed to ensure that qualified personnel properly gather
and evaluate the information used to determine that the requirements to obtain information have been met.
I am aware that there are significant penalties for false certification including fine and imprisonment." 
g. A description of how the requirements to obtain the information in Paragraph 4 (i through iv) [of this 
attachment] are met. 
2. When 90 percent or more of any of the cumulative pollutant loading rates are reached, the person who
applies the bulk sewage sludge shall report the information in Paragraphs 1 a through d of the Record
keeping Requirements of this attachment annually on February 19. Reports shall be submitted to EPA at
the address in the Monitoring and Reporting section of this permit. 
3. The person who applies the bulk sewage sludge shall develop and maintain the following information for
five years: 
a. The following certification statement: 
"I certify, under penalty of law, that the management practices in § 503.14 have been met for each site on
which bulk sewage sludge is applied. This determination has been made under my direction and
supervision in accordance with the system designed to ensure that qualified personnel properly gather and
evaluate the information used to determine that the management practices have been met. I am aware that
there are significant penalties for false certification including the possibility of fine and imprisonment." 
b. A description of how the management practices in the Management Practices Paragraph of this attachment
are met for each site. 
c. When Class B pathogen requirements are met, the following certification statement: 
"I certify, under penalty of law, that the site restrictions in § 503.32(b)(5), and have been met for each site on
which bulk sewage sludge is applied. This determination has been made under my direction and
supervision in accordance with the system designed to ensure that qualified personnel properly gather and
evaluate the information used to determine that the management practices and site restrictions have been
met. I am aware that there are significant penalties for false certification including the possibility of fine and
imprisonment." 
g. A description of how the site restrictions in the Site Restrictions Paragraphs of this attachment are met for
each site.

Attachment J 
Pathogens 
(40 CFR § 503.32) 
Class A - Alternative 1 (503.32(a)(3)) 
(i) Either the density of fecal coliform in the sewage sludge shall be less than 1000 Most Probable Number per gram
of total solids (dry weight basis), or the density of Salmonella sp. bacteria in the sewage sludge shall be less
than three M o s t Probable Number per four grams of total solids (dry weight basis) at the time the sewage sludge
is used or disposed; at the time the sewage sludge is prepared for sale or give away in a bag or other container
for application to the land; or at the time the sewage sludge or material derived from sewage sludge is prepared
to meet the requirements in §503.10(b), §503.10(c), §503.10(e), or §503.10(f). 
(ii) The temperature of the sewage sludge that is used or disposed shall be maintained at a specific value for a
period of time. 
(A) When the percent solids of the sewage sludge is seven percent or higher, the temperature of the
sewage sludge shall be 50 degrees Celsius or higher; the time period shall be 20 minutes or longer; and
the temperature and time period shall be determined using equation (3), except when small particles
of sewage sludge are heated by either warmed gases or an immiscible liquid. 
D = 131,700,000 (3) 
10 0.1400t 
Where, 
D = time in days. 
t = temperature in degrees Celsius. 
(B) When the percent solids of the sewage sludge is seven percent or higher and small particles of sewage
sludge are heated by either warmed gases or an immiscible liquid, the temperature of the sewage
sludge shall be 50 degrees Celsius or higher; the time period shall be 15 seconds or longer; and the
temperature and time period shall be determined using equation (3). 
(C) When the percent solids of the sewage sludge is less than seven percent and the time period is at least
15 seconds, but less than 30 minutes, the temperature and time period shall be determined using
equation (3). 
(D) When the percent solids of the sewage sludge is less than seven percent; the temperature of the
sewage sludge is 50 degrees Celsius or higher; and the time period is 30 minutes or longer, the
temperature and time period shall be determined using equation (4). 
D = 50,070,000 (4) 
10 0.1400t 
Where, 
D = time in days. 
t = temperature in degrees Celsius. 
Class A - Alternative 2 (503.32(a)(4)) 
(i) Either the density of fecal coliform in the sewage sludge shall be less than 1000 Most Probable Number per gram
of total solids (dry weight basis), or the density of Salmonella sp. bacteria in the sewage sludge shall be less

than three M o s t Probable Number per fourgrams of total solids (dry weight basis) at the time the sewage sludge
is used or disposed; at the time the sewage sludge is prepared for sale or give away in a bag or other container
for application to the land; or at the time the sewage sludge or material derived from sewage sludge is prepared
to meet the requirements in §503.10(b), §503.10(c), §503.10(e), or §503.10(f). 
(ii)(A) The pH of the sewage sludge that is used or disposed shall be raised to above 12 and shall remain above 12
for 72 hours. 
(B) The temperature of the sewage sludge shall be above 52 degrees Celsius for 12 hours or longer during
the period that the pH of the sewage sludge is above 12. 
(C) At the end of the 72 hour period during which the pH of the sewage sludge is above 12, the sewage
sludge shall be air dried to achieve a percent solids in the sewage sludge greater than 50 percent. 
Class A - Alternative 3 (503.32(a)(5)) 
(i) Either the density of fecal coliform in the sewage sludge shall be less than 1000 Most Probable Number per gram
of total solids (dry weight basis), or the density of Salmonella sp. bacteria in sewage sludge shall be less than
three Most Probable Number per four grams of total solids (dry weight basis) at the time the sewage sludge is
used or disposed; at the time the sewage sludge is prepared for sale or give away in a bag or other container
for application to the land; or at the time the sewage sludge or material derived from sewage sludge is prepared
to meet the requirements in §503.10(b), §503.10(c), §503.10(e), or §503.10(f). 
(ii)(A) The sewage sludge shall be analyzed prior to pathogen treatment to determine whether the sewage sludge
contains enteric viruses. 
(B) When the density of enteric viruses in the sewage sludge prior to pathogen treatment is less than one Plaque-
forming Unit per four grams of total solids (dry weight basis), the sewage sludge is Class A with respect to
enteric viruses until the next monitoring episode for the sewage sludge. 
(C) When the density of enteric viruses in the sewage sludge prior to pathogen treatment is equal to or greater than
one Plaque-forming Unit per four grams of total solids (dry weight basis), the sewage sludge is Class A with
respect to enteric viruses when the density of enteric viruses in the sewage sludge after pathogen treatment
is less than one Plaque-forming Unit per four grams of total solids (dry weight basis) and when the values or
ranges of values for the operating parameters for the pathogen treatment process that produces the sewage
sludge that meets the enteric virus density requirement are documented. 
(D) After the enteric virus reduction in (ii)(C) of this s u b s ection is demonstrated for the pathogen treatment
process, the sewage sludge continues to be Class A with respect to enteric viruses when the values for the
pathogen treatment process operating parameters are consistent with the values or ranges of values
documented in (ii)(C) of this subsection. 
(iii)(A) The sewage sludge shall be analyzed prior to pathogen treatment to determine whether the sewage sludge
contains viable helminth ova. 
(B) When the density of viable helminth ova in the sewage sludge prior to pathogen treatment is less than one per
four grams of total solids (dry weight basis), the sewage sludge is Class A with respect to viable helminth ova
until the next monitoring episode for the sewage sludge. 
(C) When the density of viable helminth ova in the sewage sludge prior to pathogen treatment is equal to or greater
than one per four grams of total solids (dry weight basis), the sewage sludge is Class A with respect to viable
helminth ova when the density of viable helminth ova in the sewage sludge after pathogen treatment is less
than one per four grams of total solids (dry weight basis) and when the values or ranges of values for the

operating parameters for the pathogen treatment process that produces the sewage sludge that meets the viable
helminth ova density requirement are documented. 
(D) After the viable helminth ova reduction in (iii)(C) of this subsection is demonstrated for the pathogen treatment
process, the sewage sludge continues to be Class A with respect to viable helminth ova when the values for
the pathogen treatment process operating parameters are consistent with the values or ranges of values
documented in (iii)(C) of this subsection. 
Class A - Alternative 4 (503.32(a)(6)) 
(i) Either the density of fecal coliform in the sewage sludge shall be less than 1000 Most Probable Number per gram 
of total solids (dry weight basis) , or the density of Salmonella sp. bacteria in the sewage sludge shall be less 
than three M o s t Probable Number per four grams of totalsolids (dry weight basis) at the time the sewage sludge 
is used or disposed; at the time the sewage sludge is prepared for sale or give away in a bag or other container 
for application to the land; or at the time the sewage sludge or material derived from sewage sludge is prepared 
to meet the requirements in §503.10(b), §503.10(c), §503.10(e), or §503.10(f). 
(ii) The density of enteric viruses in the sewage sludge shall be less than one Plaque-forming Unit per four grams 
of total solids (dry weight basis) at the time the sewage sludge is used or disposed; at the time the sewage 
sludge is prepared for sale or give away in a bag or other container for application to the land; or at the time the 
sewage sludge or material derived from sewage sludge is prepared to meet the requirements in §503.10(b), 
§503.10(c), §503.10(e), or §503.10(f), unless otherwise specified by the permitting authority. 
(iii) The density of viable helminth ova in the sewage sludge shall be less than one per four grams of total solids 
(dry weight basis) at the time the sewage sludge is used or disposed; at the time the sewage sludge is prepared 
for sale or give away in a bag or other container for application to the land; or at the time the sewage sludge 
or material derived from sewage sludge is prepared to meet the requirements in §503.10(b), §503.10(c), 
§503.10(e), or §503.10(f), unless otherwise specified by the permitting authority. 
Class A - Alternative 5 (503.32(a)(8)) 
(i) Either the density of fecal coliform in the sewage sludge shall be less than 1000 Most Probable Number per gram
of total solids (dry weight basis), or the density of Salmonella , sp. bacteria in the sewage sludge shall be less
than three M o s t Probable Numberper four grams of total solids (dry weight basis) at the time the sewage sludge
is used or disposed; at the time the sewage sludge is prepared for sale or give away in a bag or other container
for application to the land; or at the time the sewage sludge or material derived from sewage sludge is prepared
to meet the requirements in §503.10(b), §503.10(c), §503.10(e), or §503.10(f). 
(ii) Sewage sludge that is used or disposed shall be treated in one of the Processes to Further Reduce Pathogens
described in Appendix B. 
Class A - Alternative 6 (503.32(a)(8) 
(i) Either the density of fecal coliform in the sewage sludge shall be less than 1000 Most Probable Number per gram
of total solids (dry weight basis), or the density of Salmonella , sp. bacteria in the sewage sludge shall be less
than three M o s t Probable Number per four grams of total solids (dry weight basis) at the time the sewage sludge
is used or disposed; at the time the sewage sludge is prepared for sale or give away in a bag or other container
for application to the land; or at the time the sewage sludge or material derived from sewage sludge is prepared
to meet the requirements in §503.10(b), §503.10(c), §503.10(e), or §503.10(f). 
(ii) Sewage sludge that is used or disposed shall be treated in a process that is equivalent to a Process to Further
Reduce Pathogens, as determined by the permitting authority.

Class B - Alternative 1 (503.32(b)(2)) 
(i) Seven samples of the sewage sludge shall be collected at the time the sewage sludge is used or disposed. 
(ii) The geometric mean of the density of fecal coliform in the samples collected in (2)(i) of this subsection shall be
less than either 2,000,000 M o s t Probable Number per gram of total solids (dry weight basis) or 2,000,000 Colony
Forming Units per gram of total solids (dry weight basis). 
Class B - Alternative 2 (503.32(b)(3)) 
Sewage sludge that is used or disposed shall be treated in one of the Processes to Significantly Reduce
Pathogens described in Appendix B. 
Class B - Alternative 3 (503.32(b)(4)) 
Sewage sludge that is used or disposed shall be treated in a process that is equivalent to a Process to
Significantly Reduce Pathogens, as determined by the permitting authority.

Attachment K 
Vector Attraction Reduction 
Alternative 1 - (503.33(b)(1)) 
The mass of volatile solids in the sewage sludge shall be reduced by a minimum of 38 percent. 
Alternative 2 - (503.33(b)(2)) 
When the 38 percent volatile solids reduction requirement in §503.33(b)(1) cannot be met for an
anaerobically digested sewage sludge, vector attraction reduction can be demonstrated by digesting a
portion of the previously digested sewage sludge anaerobically in the laboratory in a bench-scale unit for
40 additional days at a temperature between 30 and 37 degrees Celsius. When at the end of the 40 days, the
volatile solids in the sewage sludge at the beginning of that period is reduced by less than 17 percent,
vector attraction reduction is achieved. 
Alternative 3 - (503.33(b)(3)) 
When the 38 percent volatile solids reduction requirement in §503.33(b)(1) cannot be met for an aerobically
digested sewage sludge, vector attraction reduction can be demonstrated by digesting a portion of the
previously digested sewage sludge that has a percent solids of two percent or less aerobically in the
laboratory in a bench-scale unit for 30 additional days at 20 degrees Celsius. When at the end of the 30
days, the volatile solids in the sewage sludge at the beginning of that period is reduced by less than 15
percent, vector attraction reduction is achieved. 
Alternative 4 - (503.33(b)(4) 
The specific oxygen uptake rate (SOUR) for sewage sludge treated in an aerobic process shall be equal to or
less than 1.5 milligrams of oxygen per hour per gram of total solids (dry weight basis) at a temperature of 20
degrees Celsius. 
Alternative 5 - (503.33(b)(5)) 
Sewage sludge shall be treated in an aerobic process for 14 days or longer. During that time, the
temperature of the sewage sludge shall be higher than 40 degrees Celsius and the average temperature of
the sewage sludge shall be higher than 45 degrees Celsius. 
Alternative 6 - (503.33(b)(6)) 
The pH of sewage sludge shall be raised to 12 or higher by alkali addition and, without the addition of more
alkali, shall remain at 12 or higher for two hours and then at 11.5 or higher for an additional 22 hours. 
Alternative 7 - (503.33(b)(7)) 
The percent solids of sewage sludge that does not contain unstabilized solids generated in a primary
wastewater treatment process shall be equal to or greater than 75 percent based on the moisture content
and total solids prior to mixing with other materials. 
Alternative 8 - (503.33(b)(8)) 
The percent solids of sewage sludge that contains unstabilized solids generated in a primary wastewater
treatment process shall be equal to or greater than 90 percent based on the moisture content and total
solids prior to mixing with other materials.

Alternative 9 - (503.33(b)(9)) 
(a) Sewage sludge shall be injected below the surface of the land. 
(b) No significant amount of the sewage sludge shall be present on the land surface within one hour after the
sewage sludge is injected. 
Alternative 10 - (503.33(b)(10)) 
Sewage sludge applied to the land surface or placed on a surface disposal site shall be incorporated into the
soil within six hours after application to or placement on the land. 
Alternative 11 - (503.33(b)(11)) 
Sewage sludge placed on an active sewage sludge unit shall be covered with soil or other material at the
end of each operating day.

Attachment L 
Sampling and Analysis 
(a) Sampling: Representative samples of sewage sludge that is applied to the land, placed on a surface disposal
site, or fired in a sewage sludge incinerator shall be collected and analyzed. 
(b) Analytical methods: The following methods shall be used to analyze samples of sewage sludge. 
(1) Enteric viruses
ASTM Designation: D 4994-89, "Standard Practice for Recovery of Viruses From Wastewater
Sludges", 1992 Annual Book of ASTM Standards: Section 11-Water and Environmental
Technology, ASTM, 1916 Race Street, Philadelphia, PA 19103-1187. 
(2) Fecal coliform
Part 9221 E or Part 9222D., "Standard Methods for the Examination of Water and Wastewater",
18th Edition, 1992, American Public Health Association, 1015 15th Street, NW., Washington, DC
20005 
(3) Helminth ova
Yanko, W.A., "Occurrence of Pathogens in Distribution and Marketing Municipal Sludges", EPA
600/1-87-014, 1987. National Technical Information Service, 5285 Port Royal Road, Springfield,
Virginia 22161 (PB 88-154273/AS). 
(4) Inorganic pollutants
"Test Methods for Evaluating Solid Waste, Physical/Chemical Methods", EPA Publication SW
846, Second Edition (1982) with Updates I (April 1984) and II (April 1985) and Third Edition
(November 1986) with Revision I (December 1987). Second Edition and Updates I and II are
available for the National Technical Information Service, 5285 Port Royal Road, Springfield,
Virginia 22161 (PB-87-120-291). Third Edition and Revision I are available from Superintendent of
Documents, Government Printing Office, 941 North Capital Street, NE., Washington, DC 20002
(Document Number 955-001-00000-1). 
(5) Salmonella sp. bacteria
Part 9260 D., "Standard Methods for the Examination of Water and Wastewater", 18th Edition,
1992, American Public Health Association, 1015 15th Street, NW., Washington, DC 20005; or 
Kenner, B.A. and H.P. Clark, "Detection and enumeration of Salmonella and Pseudomonas
aeruginosa", Journal of the Water Pollution Control Federation, Vol.46, no 9, September 1974, pp.
2163-2171. Water Environment Federation, 601 Wythe Street, Alexandria, Virginia 22314 
(6) Specific oxygen uptake rate
Part 2710 B., "Standard Methods for the Examination of Water and Wastewater", 18th Edition,
1992, American Public Health Association, 1015 15th Street, NW, Washington, DC 20005 
(7) Total, fixed and volatile solids
Part 2540 G., "Standard Methods for the Examination of Water and Wastewater", 18th Edition,
1992, American Public Health Association, 1015 15th Street, NW, Washington, DC 20005 
(c) Percent volatile solids reduction: Shall be calculated using procedures in "Environmental Regulations and
Technology - Control of Pathogens and Vectors in Sewage Sludge", Appendix C, EPA 625/R-92/013,
December 1992, U.S. Environmental Protection Agency, Office of Research and Development, Washington,
DC 20460

Attachment M 
Nine Minimum Controls 
Documentation and Implementation Guidance 
The following guidance is for communities preparing documentation to demonstrate adequate implementation of the
nine minimum technology based control measures for combined sewer overflows. For further information see 
Combined Sewer Overflows: Guidance for Nine Minimum Controls (EPA MAY 1995)(EPA 832-B-95-003) . 
EPA has made a Best Professional Judgement (BPJ) determination that adequate implementation of technology
based requirements, Best Practicable Control Technology Currently Available (BPT), Best Conventional Pollutant
Control Technology (BCT) to control and abate conventional pollutants, and Best Available Technology
Economically Achievable (BAT) to control and abate non-conventional and toxic pollutants, must include
implementation of the nine minimum controls. 
Documentation Requirements 
Documentation should provide sufficient information to demonstrate: 
- that alternatives were considered for each of the nine minimum control measures. 
- the reasoning for the alternatives that were selected. 
- that the selected alternatives have been implemented. 
- that the permittee has developed a schedule for actions that have been selected but not yet fully
implemented. 
Nine Minimum Controls (NMC) 
The following is a summary of specific information which must be included in the documentation of each of the
NMCs. 
1. Proper operation and regular maintenance programs for the sewer system and combined sewer overflow
points. 
a. An organizational chart showing the staff responsible for operation and maintenance (O&M) of
the combined sewer system. Document that organization and staffing levels are adequate. 
b. The funding allocated for O&M of the combined sewer system. Document that funding is
adequate. 
c. A list of facilities and structures that are critical to the performance of the combined sewer system,
including all regulators, tide gates, pumping stations, and sections of sewer lines which are prone
to sedimentation or obstruction. Include an inspection plan which identifies the locations,
frequency, procedures, documentation, and reporting of periodic and emergency inspections and
maintenance. Document that these facilities are adequately operated and maintained. 
d. A summary of safety training and equipment provided to inspection and maintenance personnel.
For instance, workers entering sewers must be trained and equipped for confined space entry.
Document that training listed is adequate. 
e. A summary of technical training and maintenance equipment provided to inspection and
maintenance personnel. Document that training and equipment are adequate to maintain the
facilities identified in item 1.c. above.

2. Maximum Use of the Collection System for Storage 
a. Collection system inspection: This should focus on the identification of maintenance or design
deficiencies that restrict the use of otherwise available system capacity. This evaluation should
document that inadequate regulators, piping bottlenecks, and pumping deficiencies have been
identified and corrected, or scheduled for correction. Where increased inspection and/or
maintenance is proposed, this shall be reflected in the inspection plan required in item 1.c. 
b. Tide gate maintenance and repair: Tide gates prevent significant volumes of water from entering
the conveyance system, thereby freeing up system storage capacity during wet weather periods.
Where appropriate, document that tide gate maintenance and repair procedures are adequate. 
c. Adjustment of regulator settings: Adjustment of regulating devices can increase in-system
storage of CSO flows and maximize transport to the POTW. Care should be taken to ensure that
the regulator adjustment will not result in unacceptable surcharging of the system. Document that
regulators have been adjusted to optimum settings. The method by which the community
determined the optimum regulator setting (e.g. modeling, trial and error) shall be included in the
documentation. 
d. Removal of obstructions to flow: Document that accumulations of debris which may cause flow
restrictions are identified, and debris is removed routinely. Documentation shall include a
summary of the locations where sediment is removed, the number of times each year the sediment
is removed and the total quantity of material removed each year. 
3. Review and Modification of the Industrial Pretreatment Program to assure CSO impacts are minimized. 
a. Review legal authority: Review the community's legal authority (i.e. pretreatment program, sewer
use ordinance) to regulate non domestic discharges to its collection system. Identify those
activities for which the community has or can obtain legal authority to address CSO induced water
quality violations. For example, does the community have legal authority to require non domestic
dischargers to store wastewater discharges during precipitation events or can the community
require non domestic dischargers to implement runoff controls? 
b. Inventory non domestic dischargers: Identify those non domestic discharges that may, through
quantity of flow or pollutant concentration or loadings, contribute to CSO induced water quality
violations, 
c. Assess the significance of identified dischargers to CSO control issues: Assess whether the
identified non domestic sources cause or contribute to CSO induced water quality standards by
using monitoring, dilution calculations or other reasonable methods. 
d. Evaluate and propose feasible modifications: Identify, evaluate, and propose site-specific
modifications to the pretreatment program which would address the non domestic dischargers
identified as significant. Modifications which shall be considered include; 
Volume-related controls: Document that detaining wastewater flows (sanitary, industrial, and/or
storm water) within the industrial facility until they can be safely discharged to the POTW for
treatment was considered and implemented where reasonable. 
Pollutant Load-related controls: Document that reduction of concentrations of pollutants that
enter the collection system during storm periods was considered and implemented where

reasonable. Methods to be considered for reducing pollutant concentrations from stormwater
runoff controls include structural and non-structural controls such as covering material storage
areas, reducing impervious area, detention structures, and good housekeeping. 
4. Maximization of flow to the POTW for treatment 
It is recognized that most of the actions recommended for maximization of the collection system for storage
will also serve to maximize flow to the POTW. In addition to optimizing those controls to maximize flow to
the POTW, the following specific controls should be evaluated and implemented where possible; 
a. Use of off-line or unused POTW capacity for storage of wet weather flows. 
b. Use of excess primary treatment for treatment of wet weather flows. If the use of excess primary
capacity will result in violations of the community's NPDES permit limits, the community shall get
approval of the proposed bypass from the permitting authority prior to implementation. 
5. Prohibition of CSO discharges during dry weather 
a. Document that the community's monitoring and inspections are adequate to detect and correct dry
weather overflows (DWOs) in a timely manner. 
b. Document that DWOs due to inadequate sewer system capacity have been eliminated. If
elimination is scheduled but not yet completed, the documentation shall include the schedule. 
c. Document that DWOs due to clogging of pipes and regulators or due to other maintenance
problems have been eliminated to the maximum extent practicable. Increased inspection and
maintenance of problem areas must be considered as well as modification or replacement of
existing structures. 
6. Control of Solid and Floatable Material in CSO Discharges 
Document that low cost control measures have been implemented which reduce solids and floatables
discharged from CSOs to the maximum extent practicable. Alternatives which shall be considered include; 
a. baffles in regulators or overflow structures. 
b. trash racks in CSO discharge structures. 
c. static screens in CSO discharge structures. 
d. catch basin modifications. 
e. end of pipe nets. 
f. outfall booms (on surface of receiving water) 
7. Pollution prevention programs that focus on contaminant reduction activities. 
a. Prevention: through public education or increased awareness. For example, a water conservation
outreach effort could result in less dry weather sanitary flow to the POTW and an increase in the
volume of wet weather flows that can be treated at the POTW. 
b. Control of disposal: through the use of garbage receptacles, more efficient garbage collection, or

again, through public education. 
c. Anti-litter campaigns: Campaigns through public outreach and public service announcements can
be employed to educate the public about the effects of littering, overfertilizing, pouring used motor
oil down catch basins, etc. 
d. Illegal dumping: Programs such as law enforcement and public education can be used as controls
for illegal dumping of litter, tires, and other materials into water bodies or onto the ground. Free
disposal of these products at centrally located municipal dump sites can also reduce the
occurrence of illegal dumping. 
e. Street cleaning 
f. Hazardous waste collection days: Communities are encouraged to schedule one or two days a
year where household hazardous wastes can be brought to a common collection area for collection
and environmentally safe disposal. 
8. Public notification to ensure that the public receives adequate notification of CSO occurrences and CSO
impacts. 
The objective of this control element is to ensure that the public receives adequate notification of CSO
impacts on pertinent water use areas. Of particular concern are beach and recreational areas that are
affected by pollutant discharges in CSOs. 
Where applicable, the permittee shall provide users of these types of areas with a reasonable opportunity to
inform themselves of the existence of potential health risks associated with the use of the water body
(bodies). The minimum control level, found in Section C.2.f. of the permit is posting of CSO discharge
points. 
9. Monitoring to effectively characterize CSO impacts and the efficacy of CSO controls. 
As stated in the permit,in Section C.2.f. the minmum requirement is quantification and recording at the
outfall. If possible, the permittee shall initiate monitoring, measuring and/or inspection activities above and
beyond the minimum control levels specified in the permit. The purpose of these additional monitoring
and/or inspection events is to better characterize quality of the CSOs and their impacts on all receiving
waters. Examples of such events include CSO monitoring or receiving water monitoring for pollutants of
particular concern.

Massachusetts Water Resources Authority 
effluent outfall monitoring plan: 
Phase II post-discharge monitoring 
Massachusetts Water Resources Authority 
Charlestown Navy Yard 
100 First Avenue 
Boston, MA 02129 
(617) 242-6000 
December 1997 
Environmental Quality Department
ms-044

citation: 
MWRA .1997. Massachusetts Water Resources Authority effluent outfall monitoring plan: Phase II post
discharge monitoring. MWRA Enviro. Quality Dept. Misc. Rpt. No. ms-044. Massachusetts Water Resources
Authority , Boston, MA. 61 pp.

___________________________________________________________________________________________ 
ACKNOWLEDGMENTS 
The Massachusetts Executive Office of Environmental Affairs organized an Outfall Monitoring Task force
to provide advice, guidance, and oversight for monitoring of the MWRA effluent outfall in Massachusetts
Bay. The membership (as of May 1997) of the Task Force is: 
Members from State Agencies (Alternate members are shown in parentheses):
Department of Environmental Protection Russ Isaac
Division of Marine Fisheries Leigh Bridges, (Jack Schwartz)
Mass. Coastal Zone Management Peg Brady, (Chris Krahforst) 
Members from Federal Agencies:
National Marine Fisheries Service Sal Testaverde
US Geological Survey Rich Signell
US Army Corps of Engineers Tom Fredette
Environmental Protection Agency Matt Liebman, (Janet Labonte) 
(Dave Tomey) 
Members from regions: 
Boston 
Wastewater Advisory Committee Susan Redlich 
Save the Harbor/Save the Bay Jodi Sugennan 
Northshore 
Safer Water in Massachusetts Polly Bradley 
Cape Cod 
Center for Coastal Studies Russ DeConti 
Cape Cod Commission Julie Early, (Susan Nickerson) 
Members from the scientific community: 
Robert Buchsbaum, Don Cheney, John Farrington, Gene Gallagher, Jonathan Garber, 
Diane Gould, Norbert Jaworski, Joe Montoya, Judy Pederson, Jerry Schubel [chair] 
Non-voting participants: 
MWRA staff: Mike Connor, Ken Keay, Mike Mickelson 
MWRA consultants: Jim Blake, Steve Cibik, Don Galya 
Drafts of this document were prepared by Windsor Sung and Carlton Hunt. 
December, 1997

CONTENTS 
1.0 INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1 
1.1 Objectives for Post-Discharge Monitoring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . 1-5 
1.2 Components of the Monitoring Plan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6 
1.3 Contingency Plan Thresholds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6 
2.0 EFFLUENT MONITORING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1 
2.1 Overview of Phase I Baseline Studies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1 
2.2 Contingency Plan Trigger Parameters and Threshold Levels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2 
2.3 Phase II Monitoring Plan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5 
2.4 Data Evaluation and Comparison to Thresholds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-6 
3.0 WATER COLUMN MONITORING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1 
3.1 Overview of Phase I Baseline Studies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1 
3.2 Contingency Plan Trigger Parameters and Threshold Levels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3 
3.3 Phase II Monitoring Plan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-7 
3.3.1 Nearfield . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-7 
3.3.2 Farfield . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-13 
3.3.3 Special Studies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-14 
3.4 Data Evaluation and Comparison to Thresholds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-15 
4.0 BENTHIC MONITORING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1 
4.1 Overview of Phase I Baseline Studies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1 
4.2 Contingency Plan Trigger Parameters and Threshold Levels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-5 
4.3 Phase II Monitoring Plan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-7 
4.4 Data Evaluation and Comparison to Thresholds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-9 
5.0 FISH AND SHELLFISH MONITORING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1 
5.1 Overview of Phase I Baseline Studies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1 
5.2 Contingency Plan Trigger Parameters and Threshold Levels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-4 
5.3 Phase II Monitoring Plan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-4 
5.4 Data Evaluation and Comparison to Threshold Values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-6 
5.4.1 Contaminant Concentration in Fish and Shellfish . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-9 
5.4.2 Ecological Health Indicators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-9 
6.0 REFERENCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-1 
i December, 1997

LIST OF TABLES 
1-1 Schedule of Treatment Upgrades and Monitoring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3 
1-2 Summary of Trigger Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4 
2-1 Trigger Parameters for Effluent . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-4 
3-1 Trigger Parameters for Water Column . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-4 
3-2 Analysis Group for Each Station and Depth, Nearfield Survey . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-10 
3-3 Analysis Group for Each Station and Depth, Farfield Survey . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-11 
3-4 Chemical and Biological Analysis Performed in Each Analysis Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-12 
4-1 Revised Station Grouping after Coats (1995) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2 
4-2 Trigger Parameters for the Benthic Environment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-6 
5-1 Chemistry Analyses for Fish and Shellfish Monitoring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-2 
5-2 Trigger Parameters for Fish and Shellfish . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-5 
5-3 Data Sources and Comparison for Trigger Parameter Threshold Values . . . . . . . . . . . . . . . . . . . . . . . . . . 5-7 
ii December, 1997

LIST OF FIGURES 
1-1 Distances of the New Outfa11 from Selected Sensitive Areas in Massachusetts and
Cape Cod Bays . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2 
2-1 Tota1 Nitrogen Load Discharged from the Deer Island and Nut Island Treatment 
Plants from 1990 to 1996 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3 
3-1 Nearfield Stations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-8 
3-2 Farfield Stations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-9 
4-1 Nearfield and Midfield Soft Bottom Stations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3 
4-2 Station Locations for Grab Samples, Farfield . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-4 
4-3 Transect Locations for Nearfield Hard-bottom Video Survey . . . . . . . . . . . . . . . . . . . . . . . . . . 4-8 
4-4 Benthic Nutrient Flux Sampling Locations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-10 
5-1 Sampling Stations for Winter Flounder, Lobster and Mussels . . . . . . . . . . . . . . . . . . . . . . . . . . 5-3 
iii December, 1997

1.0 INTRODUCTION 
The Massachusetts Water Resources Authority (MWRA) is responsible for the construction and operation of a new sewage
effluent outfall from the Deer Island Wastewater Treatment Plant. The new outfall will be located in Massachusetts Bay
approximately 15 km from the Deer Island Plant in a water depth of 32 m (Figure 1-1). Improved effluent treatment,
cessation of sludge discharge (accomplished in December of 1991), and moving the wastewater discharge from within the
confines of Boston Harbor are expected to result in a significant improvement in water and sediment quality within the
Harbor area without causing harm to the environment of Massachusetts and Cape Cod Bays (EPA 1988). Operation of the
new outfall, originally scheduled for July 1995, has been delayed until 1998 (Table 1-1). 
The MWRA is required to monitor for environmental impacts of the new outfall. The new outfall will be regulated through a
permit issued by the U.S . Environmental Protection Agency and the Massachusetts Department of Environmental Protection
under the National Pollutant Discharge Elimination System (NPDES). The EPA Supplemental Environmental Impact
Statement (SEIS) (EPA 1988) requires monitoring for compliance with that NPDES permit, for assessing impact of the
discharge beyond that which was identified in the SEIS as acceptable, and for collecting data useful for outfall management
considerations. An amendment to the 1986 court order requiring the MWRA to upgrade their treatment facilities and effluent
discharge outfall expanded on the data needs for outfall management (MWRA 1990). Included in this agreement was
MWRA's commitment to implement "long term biological and chemical monitoring to describe existing conditions and
evaluate the impacts of the treatment facility discharge." The information gained through these studies was to provide the
fundamental understanding of the variability and ecological functioning of the Massachusetts Bay system. 
Under the monitoring approach developed and adopted by MWRA and the Outfall Monitoring Task Force (OMTF)
established by the Massachusetts Executive Office of Environmental Affairs (EOEA) to oversee the monitoring program,
areas of concern (public, scientific, and regulatory) were identified following guidance for coastal monitoring included in
NRC (1990). Using this information, a draft Phase I baseline monitoring plan was developed (MWRA 1991), reviewed, and
accepted by EOEA with revisions (Pederson 1992). This plan described and discussed the ecological and other potential
responses (perturbations) that were of concern (Table 1-2) and the field and laboratory studies that were necessary to acquire
data to address these concerns. Details of the field and analytical program conducted under Phase I are described in a series
of Combined Work/Quality Assurance Project Plans (Butler et al. 1995, Bowen et al. 1997, Blake and Hilbig 1995, Mitchell
et al. 1995) with subsequent program revisions as data became available and in response to other recommendations (Hunt and
Steinhauer 1994a,b; Hunt et al. 1994, McCarthy et al. 1996a,b,c). 
December, 1997 1-1

FIGURE 1-1

Distances of the new outfall from selected sensitive
areas in Massachusetts and Cape Cod Bays. The
exisiting outfalls are near Deer Island and the more
southerly Nut Island. The new outfall is 9.5 miles
from Deer Island.

Cape Cod

Bay

X New Outfall

X Existing Outfalls

421s?

42°00"

41°45"

70°15" 70°00"

1-2

December, 1997

TABLE 1-1 
Schedule of Treatment Upgrades and Monitoring 
Year Operation 
1991 The Phase I Outfall Monitoring Plan formulated the monitoring hypotheses to be tested.
Sludge discharge into Boston Harbor ceased in December. 
1992 Baseline monitoring initiated. 
1995 New primary treatment facility on Deer Island became operational in January. Draft
Contingency Plan developed. 
1997 MWRA revised the Contingency Plan (2/97) in response to comments. Draft NPDES
permit for relocated discharge will be presented for comment. South systems flows may
be sent to Deer Island via the completed (10/97) inter-island tunnel. 
1997 to 1999 Secondary treatment batteries will become operational on Deer Island in phases. (7/97 for
battery A, 12/97 for battery B, 12/99 for Battery C; each battery is 160 MGD). 
1998 When the outfall is relocated (scheduled for 10/98), the monitoring program changes in
name from Phase I (baseline) to Phase II (post-discharge), though there is consistency in
the monitoring effort. 
2001 Review first 3 years of post-discharge monitoring results to evaluate the impacts of the
outfall relocation, the level of monitoring effort, and the appropriateness of monitoring
hypotheses and Contingency Plan provisions. 
December, 1997 1-3

TABLE 1-2 
Summary of Trigger Parameters 
Monitoring Area Trigger Parameter 
Effluent Total Suspended Solids 
Biochemical Oxygen Demand 
Pathogenic Indicator Bacteria 
Nitrogen Loading 
Toxic Metals and Organic Chemicals 
Toxicity Testing 
Floatable 
Oil and Grease 
Plant Compliance with Permit Limits 
Water Column Dissolved Oxygen Concentration 
Dissolved Oxygen Respiration Rate 
Chlorophyll 
Nuisance and Noxious Algae 
Zooplankton 
Diffuser Mixing 
Benthos Benthic Community Structure 
Sediment Oxygen 
Sediment Toxic Metal and Organic
Chemicals 
Fish and Shellfish Mercury and PCBs in Flounder,
Lobster, and Mussels 
Lead in Mussels 
Lipophilic Toxic Contamination 
Liver Disease in Flounder 
December, 1997 1-4

The original discharge into Massachusetts Bay was planned for 1995. This is now projected for October of 1998. This has
allowed collection of 6 years of baseline data, from 1992 to 1998, rather than the original 3 years required. 
This report is the Post-Discharge Monitoring Plan (hereafter just referred to as the Monitoring Plan) for 1999 to 2001. The
major emphasis is on the vicinity of the future outfall, with additional effort in Cape Cod and Massachusetts Bay.
Improvements in Boston Harbor are also monitored by the MWRA but will not be covered in this report due to the difference
in monitoring objectives. This Monitoring Plan describes the proposed monitoring effort and is complemented by two
companion documents: the Outfall Monitoring Overview (e.g. Galya et al. 1996) describes the results of studies implemented
under the Monitoring Plan, and the Contingency Plan (MWRA 1997) describes the response to exceedances of monitoring
hypotheses. The Contingency Plan (MWRA 1997) lists thresholds (Caution and Warning Levels) which were developed to
protect the environment and public health. The Contingency Plan also describes the various management actions that MWRA
will undertake when thresholds are exceeded. Examples of management actions include additional monitoring, development
of response plans and performance of engineering feasibility studies. The Contingency Plan provides more detailed
discussion of the potential management actions. 
1.1 Objectives for Post-Discharge Monitoring 
The primary objectives of the Monitoring Plan are: 
Objective 1: Test for compliance with NPDES permit requirements 
Objective 2: Test whether the impact of the discharge on the environment is within the bounds projected by the SEIS 
Objective 3: Test whether change within the system exceeds the Contingency Plan thresholds. 
The MWRA effluent outfall will be regulated through a NPDES permit. It has to monitor regularly to test for compliance
with the permit requirements. For example, the permit win specify allowable limits of carbonaceous Biochemical Oxygen
Demand (cBOD) and Total Suspended Solids (TSS) in the effluent based on expected performance. Monitoring for these
parameters allows MWRA to check for treatment performance, pinpoint areas of concern and correct for problems if they
exist. MWRA win submit Monthly Discharge Monitoring Reports (DMR) and report exceedance of permit limits if they
occur. 
The EPA SEIS (with concurrent opinion from the National Marine Fisheries Service, NMFS) determined that there would not
be significant water quality or biological impacts associated with the outfall. The Monitoring Plan tests for various water
quality, sedimentary and biological parameters to ensure that impacts from the discharge is within the bounds projected by
the SEIS. 
The Contingency Plan was first recommended by the NMFS. It specifies numerical or qualitative thresholds which can
suggest that effluent quality and/or environmental conditions may be changing or might be likely to change in the future. In
the event that one of these thresholds is exceeded, the Contingency Plan sets into motion a process to confirm the threshold
exceedance, to determine the causes and significance of the exceedance, and, if the suggested changes are attributable to the
effluent outfall, to identify the response that will be taken to return the trigger parameter to a level which is at or below the
relevant threshold. There is some overlap of Objective 3 with Objectives 1 and 2. The NPDES permit requirements are now a
subset of Contingency Plan thresholds. 
The Massachusetts Executive Office of Environmental Affairs (EOEA) and the U . S . EPA established the outfall monitoring
task force (OMTF) to oversee and make recommendations on the Monitoring Plan, as well as to provide guidance in 
December, 1997 1-5

interpretation and evaluation of collected data. The task force is comprised of members from the scientific community as well
as from state agencies (Department of Environmental Protection; Division of Marine Fisheries; Massachusetts Coastal Zone
Management), federal agencies (National Marine Fisheries Service, U.S. Army Corps of Engineers, U.S. Environmental
Protection Agency), and regional representatives (Boston Wastewater Advisory Committee; Save the Harbor/Save the Bay;
Safer Water in Massachusetts; Cape Cod Commission; Center for Coastal Studies). MWRA and their consultants are non
voting participants. The current chairperson of the OMTF is Dr. Jerry Schubel, president of the New England Aquarium. 
1.2 Components of the Monitoring Plan 
The Monitoring Plan is organized around the general subject headings of effluent, water column, benthic, as well as fish and
shellfish monitoring. Each of these subjects will be discussed in more detail in subsequent sections and is organized as
follows: 
• Overview of current baseline studies and important findings 
• Contingency Plan trigger parameters and threshold levels 
• Post-discharge Monitoring Plan components 
• Data evaluation and comparison to thresholds 
It should be noted that the effort described in the Monitoring Plan is more comprehensive than that necessary to just address
the Contingency Plan thresholds. This is because there is extensive interaction among water quality and ecological
parameters and natural variability in a complex environmental system such as Massachusetts Bay. The additional information
collected is necessary in order to gain a more complete understanding of the system, and provide data that will be used to
explain any changes in the system, and whether MWRA' s discharge contributed to the change. 
The Post-Discharge Phase II monitoring will require rapid evaluation of data in relation to the trigger parameters. Biological
and chemical data related to the thresholds will be examined individually ahead of the data report schedules. MWRA will
require early notification from the laboratories when Caution and Warning Levels are exceeded. 
1.3 Contingency Plan Thresholds 
The ideal Monitoring Plan requires (1) a determination of what changes are significant and (2) establishment of an
appropriate sampling and analysis plan. The issue lies with the relationship (or non relationship) between biological
importance and the statistical significance of a given result. Parkhurst (1985) stated that "deciding on the degree of biological
importance requires subjective scientific judgement, which some workers would rather not face." The Contingency Plan
thresholds are based on expected permit limits, observations from the baseline monitoring, national water quality criteria and
state standards, and in some cases, best professional judgement. A formal analysis of risk to the environment or human health
if a trigger parameter is exceeded has not been performed. 
The baseline monitoring has shown fairly large variations in the parameters being measured, as is expected in complex
environmental systems. The statistical power of detecting change has been treated at various times by Hunt and Baptiste
(1993) for fish and shellfish, Coats (1995) for sediment chemistry, and Hunt et al (1995) for water column. In general,
detectable change can be as low as 10 to 20% for dissolved oxygen; 50 to 100% for fish and shellfish parameters, as well as
some sediment chemicals; 100 to 200% for chlorophyll and dissolved inorganic nitrogen. The proposed Monitoring Plan
should provide a high probability (80%) of detecting statistically significant change. Many of the Contingency Plan
thresholds are greater than current baseline conditions (e.g. mercury levels in fish) such that statistically significant changes
would be detected long before the threshold is approached. 
December, 1997 1-6

2.0 EFFLUENT MONITORING 
The major purpose of effluent monitoring is to test for compliance with NPDES permit limits. The NPDES permit limits for
priority pollutants are expressed as concentrations in effluent; these are based on national water quality criteria, ambient
conditions, and the projected outfall dilution. The actual outfall dilution will be tested under water column studies. Effluent
monitoring will also provide accurate mass loads of various contaminants such that the fate, transport and risk of these
contaminants in Massachusetts Bays can be better assessed, if necessary. 
2.1 Overview of Phase I Baseline Studies 
MWRA currently monitors the effluent from Deer Island and Nut Island treatment plants as well as the effluent from
Combined Sewer Overflow (CSO) treatment facilities. Parameters are measured on a daily, weekly or monthly basis (e.g.
BOD and TSS are monitored daily; nutrients are monitored weekly; priority pollutants are monitored monthly). MWRA 's
Toxics Reduction And Control (TRAC) department is charged with the pre-treatment source reduction program and has
conducted studies on the source of toxic contaminants into the system. In addition, MWRA has undertaken a fairly detailed
effluent characterization study (DECS) starting from June of 1993, which has the following highlights: 
• Two-24 hour composite effluent samples were collected per month, on two of the three days of the routine
NPDES permit sample collection. 
• Samples were analyzed for trace metals, PAHS, PCBs and pesticides using methods modified to achieve
significantly lower detection levels than NPDES methods. 
• The same nutrients measured in the water column program were characterized in the effluent. These include
dissolved inorganic nitrogen compounds (ammonium, nitrite, nitrate), total dissolved nitrogen and particulate
organic nitrogen, dissolved phosphate, total dissolved and particulate organic phosphorus, urea, dissolved
silicate and biogenic silica, dissolved and particulate organic carbon. 
• Special studies of removal efficiencies for the above analytes were performed at the MWRA pilot secondary
treatment plant from 1993 to 1995. 
• Special study of potential sewage tracers in effluent were evaluated, including linear alkyl benzenes (LAB), 
Clostridium perfringens spores and stable isotope ratios of sulfur and nitrogen. 
Important Findings 
Effluent monitoring has demonstrated that, in general, improvements made at the MWRA system during the last few years
have resulted in substantial improvements in wastewater effluent quality .The 1996 daily average concentration of BODS in
Deer Island wastewater was 73 mg/l, with a range from 33 to 129 mg/l. The 1996 monthly average concentration of TSS in
Deer Island wastewater was S2 mg/l, with a range of 24 to 133 mg/l. However, secondary treatment should lower both the
BODS and TSS to below 30 mg/l in undiluted effluent. Typically, the carbonaceous BOD is less than BODS. 
The total nitrogen load being discharged by MWRA in 1996 was estimated to be 12,692 tons, which slightly exceeded the
Contingency Plan Caution Level. Figure 2-1 shows the total nitrogen load discharged from MWRA for the time period of
1990 to 1996. 
December, 1997 2-1

The monitoring program demonstrated that substantial reductions have occurred in the loading of toxic contaminants. The
pilot treatment studies demonstrated the efficacy for secondary treatment to further decrease the concentration of many toxic
contaminants. MWRA anticipates that an approximately 100-fold dilution of the effluent will occur within a few tens to
hundreds of meters of the future diffuser. This dilution will ensure that there is minimal risk to aquatic life. 
The results of these effluent characterization studies have shown the importance of using proper laboratory analysis
techniques with low detection limits. Toxic contaminant loads have been much better quantified, leading to the conclusion
that earlier load estimates were too high. 
2.2 Contingency Plan Trigger Parameters and Threshold Levels 
Based on the results of these Phase I monitoring results, MWRA (1997) revised the Contingency Plan and linked potential
management decisions to critical parameters. Trigger parameters and threshold levels applicable to the effluent are
summarized in Table 2-1. 
Many of the trigger parameters (such as TSS, cBOD) are based on U.S. EPA guidelines for secondary treatment and expected
NPDES permit limits. However, the total nitrogen loading levels are based on the original 1988 SEIS determination, NOAA
(1988) and the loadings that were assumed in the Massachusetts Bays Eutrophication Model (Hydroqual and Normandeau
1995). The Caution Level was derived as 90% of the Warning Level and rounded to 12,500. The threshold for floatables is
based on best professional judgment. The threshold for plant performance is based on standards established by EPA and the
Association of Metropolitan Sewerage Agencies to define preferred and acceptable operational achievement practices. 
December, 1997 2-2

14000

Warning Level

Caution Level

12000

M tons/yr
3

10000 ,
6000
4000
2000
0 . .

1990 1991 1992 1993
Year
FIGURE 2-1
Total nitrogen load discharged from the Deer
Island and Nut Island treatment plants from
1990-1996.

1994

1995 1996

2-3

December, 1997

TABLE 2-1 
Trigger Parameters for Effluent 
Parameter Rationale for Trigger Parameters Caution Level Warning Level 
Total nitrogen - Potential for eutrophication
based on water quality modeling
and SEIS 
12,500 mtons/yr 14,000 mtons/yr 
Toxics - Levels developed to meet water
quality criteria and NPDES
permit limits 
NPDES permit limits 
Effluent Toxicity - Direct measure of effluent
toxicity
- Based on expected NPDES
Permit limits 
Acute: LC50<50% for
shrimp; chronic: NOEC for
fish growth and sea urchin
fertilization <1.5% effluent
concentration at edge of
mixing zone. 
Carbonaceous
BOD (cBOD) 
- Provides measure of organic
loading
- Expected secondary treatment
performance 
40 mg/l weekly
25 mg/l monthly 
Fecal coliform - Surrogate for pathogens
- Based on Massachusetts Water
Quality Standards 
14,000 fecal coliforms/100
ml daily at point of
dechlorination 
Total suspended
solids (TSS) 
- Provides measure of solids
loading
- Expected NPDES permit limit 
45 mg/l weekly
30 mg/l monthly 
Floatables - Aesthetic issue and may cause
harm to marine life
- Expected removal 
5 gal/day in final collection
device 
Oil and grease of
petroleum origin 
- Aesthetic issue
- Expected NPDES permit limits 
15 mg/l weekly 
Plant performance - Expected plant performance More than 5
violations of
permit
requirements per
year 
Operating in violation of
the permit requirements
more than 5% of the time
over a year 
December, 1997 2-4

2.3 Phase II Monitoring Plan 
The major purpose for Phase II post-discharge monitoring of wastewater effluent is to test for compliance with NPDES
permit limits and other effluent thresholds, and to support evaluation of ambient monitoring data. The type of measurements,
analytical methodology, sampling frequency and location planned for Phase II monitoring are described below. 
Nutrients 
Total Kjeldahl nitrogen, ammonia, nitrate, nitrite, total phosphorus and phosphate - weekly composite. 
Toxic contaminants
Metals 
Low-detection-limit analysis of heavy metals of concern: silver, cadmium, copper, chromium,
mercury , lead, molybdenum, nickel, and zinc (The analyses incidentally yield data on arsenic,
selenium, thallium, boron, beryllium, iron, and antimony) -weekly composite. 
Organics 
Low-detection-limit analysis of 17 persistent chlorinated pesticides, an extended list of PAHS, 
and 20 PCB congeners - weekly composite. 
VOA (volatile organics) - bimonthly (every 2 months) grab. 
ABN (acid-base-neutrals) - bimonthly composite. 
Toxicity: Bioassay toxicity tests - quarterly composite. 
Other: Total residual chlorine - 3 grabs/day. Cyanide - bimonthly grab .
Organic material 
cBOD (carbonaceous biochemical oxygen demand) - daily composite. 
Human pathogens 
Pathogen indicators (total and fecal coliforms) -3 grabs/day. 
Solids 
TSS (total suspended solids) - daily composite. 
Settleable solids - daily grab. 
Floatables 
Total petroleum hydrocarbons (oil and grease of petroleum origin) - weekly grab. 
Floatables - weekly composite. 
December, 1997 2-5

Other data: 
pH - daily grab. 
alkalinity - weekly composite. 
LABs (linear alkyl benzenes) measured with PAHs above 
Special Studies 
The detailed effluent characterization study (DECS) carried out by MWRA using methods modified to achieve significantly
lower detection levels than traditional methods has shown the inadequacy of traditional NPDES laboratory analysis
methodologies. This is particularly true for trace metals and PCBS. The OMTF has recommended in 1996 to cutting back to
roughly quarterly sampling on the low detection level based on the extensive results from 1994 and 1995. The MWRA Deer
Island Laboratory is preparing to perform these low detection level measurements to supplement regular NPDES monitoring. 
Pilot treatment study will be considered for continuation to compare the performance of the secondary batteries as they come
on line. Detailed nutrient characterization and the measurement of potential sewage tracers, such as LAB and isotopes of
sulfur and nitrogen will be re-evaluated with respect to the establishment of a clear framework on how such data would
actually be used to address management concerns and aid in the decision process. These will be dropped in future monitoring
programs if they fail to provide useful information for addressing management concerns. 
The use of fecal and total coliform bacteria as indicators for human pathogens will be evaluated and the use of viral indicators
will be explored as special studies. 
2.4 Data Evaluation and Comparison to Thresholds 
The Phase II Monitoring Program will provide the information to address all of the effluent thresholds and more. In
particular, total nitrogen loadings will be available on a monthly basis (with no more than one to two month’s lag time) and
projected for the year. Effluent toxicity data and priority pollutant concentrations will be available in a similar time frame
(with perhaps longer lag times for some parameters depending on sample holding time requirements, and the sample
turnaround time within the laboratory). Daily evaluation of plant performance is achieved by comparing measured parameters
versus expected performance. 
The MWRA treatment plant is transitioning from primary treatment (new primary treatment plant came on line in 1995) to
secondary treatment (first battery to come on line in 1997) in phases, with full secondary treatment by 1999. Thus, the
effluent will be a blend of primary and secondary treated wastewaters until 1999. Measured concentrations of various effluent
parameters will be compared to the pilot treatment plant study results. Large discrepancies between predicted and observed
removal efficiencies will be resolved. 
Data Analysis 
Comparison of effluent monitoring results to threshold limits requires the calculation of weekly and monthly average values
for several parameters. For conventional parameters, calculating the average concentration of a particular parameter is
straightforward; the arithmetic mean is determined. However, when dealing with metals, pesticides, and organics, where very
frequently the analytical results were below the method detection level, certain assumptions have to be made. The adoption of
low detection limit methodologies will help overcome this weakness. Geometric means will be used in lieu of arithmetic 
December, 1997 2-6

means if it can be shown that the parameter follows a lognormal distribution. Time-average concentrations are flow-weighted
in the case of priority pollutants (metals, cyanide, pesticides/PCBs, and organic compounds). 
In addition, the flow through the wastewater treatment plant is not homogeneous. MWRA will evaluate the
representativeness of different sampling locations. 
Data Reporting 
MWRA plans to issue quarterly wastewater performance reports, with information relevant to the Contingency Plan, effluent
quality, wastewater flow, treatment plant operations and maintenance as well as residuals processing. This ensures that
pertinent information will be available to the various stakeholders, including the public, in a timely manner. 
December, 1997 2-7

3.0 WATER COLUMN MONITORING 
Potential water column issues due to the relocation of the outfall are associated with effects of the effluent organic material,
nutrients, and toxic contaminants. Of these, changes in the nutrient balance in Massachusetts and Cape Cod Bays have the
most potential for significant effects on the health of marine life in the Bay. 
Organic material occurs naturally in water bodies and may also be introduced by wastewater effluents. Decomposition of
organic material consumes dissolved oxygen (DO). Nutrients are necessary for the growth of all plants, aquatic and
terrestrial. There is concern that the nutrients provided by the MWRA effluent (in particular nitrogen) could promote
excessive algal blooms, (e.g. Kelly 1993). The excess algae could lead to conditions of low dissolved oxygen (DO) where
sensitive organisms may suffocate. 
Adding effluent to the marine environment could change the relative levels of different nutrients so that undesirable algae
dominate or are present along with useful algae. The undesirable algae could have impacts on the marine food web and
ecology or human health. 
The toxic contaminants discharged by the MWRA effluent are projected to be at extremely low concentrations. The impacts
will probably not be seen directly in the water column but may be observed in sediments and bioaccumulate through fish and
shellfish. This will be discussed in Sections 4 and 5. 
3.1 Overview of Phase I Baseline Studies 
Bigelow Laboratory for Ocean Sciences conducted a series of six surveys in 1989-1990 to collect a suite of environmental
data from Massachusetts Bay. Hydrographic measurements (temperature, salinity) were taken along with nutrients (dissolved
nitrate, nitrite, ammonium, silicate and phosphate), dissolved oxygen, chlorophyll-a, and particulate organic carbon (POC)
and nitrogen (PON) . In addition, primary production was measured, as well as phytoplankton community structure and
zooplankton volume. 
Water column monitoring was expanded in 1992, focussing on a nearfield area, a 120 square kilometer area (an area roughly
the size of Boston Harbor) centered on the future outfall. The nearfield area included 21 stations and was sampled 14 to 16
times per year from 1992 to 1994. This expanded monitoring also included 25 to 31 farfield stations covering Massachusetts
and Cape Cod Bays and Boston Harbor. These farfield stations were sampled six times per year from 1992 to 1994. 
For 1995-97 the water column monitoring design was slightly modified following review to include 17 nearfield stations
sampled 17 times per year. The farfield monitoring includes 26 stations sampled 6 times per year. In situ hydrographic
parameters are measured at each station and samples are collected for analysis of dissolved inorganic nutrients. At a subset of
the stations, samples are collected for analysis of dissolved organic carbon, nitrogen, and phosphorus; particulate carbon,
nitrogen, and phosphorus; total suspended solids; and chlorophyll-a (filtered samples) and phaeopigments and identification
and enumeration of phytoplankton and zooplankton. 14 C primary production has been measured in both the nearfield and the
farfield, with current emphasis on two nearfield stations and one farfield station adjacent to Deer Island. Water column
respiration has been measured at the productivity stations and at one offshore station. 
3-1 December, 1997

Important Findings 
Water column monitoring has shown Massachusetts Bay to be a complex and highly variable system. Much of what occurs in
the system is controlled by its seasonal physical characteristics. Massachusetts Bay undergoes an annual progression from a
vertically mixed water mass during late fall to spring, to a strongly stratified system in summer (during June to October).
While mild stratification may occur in the spring due to freshwater inputs to the system, temperature is primarily responsible
for the summer stratification. 
Water column nutrient concentrations reach annual maxima in the winter. As light increases during late winter (February-
March), a strong seasonal phytoplankton bloom typically develops which occasionally depletes nutrients throughout the
water column. This late winter bloom may be followed by a second event in late April, particularly if the first bloom is not
strong and sufficient nutrients remain. The baseline data indicate that nitrogen is typically the limiting nutrient in the system. 
As the seasonal thermocline sets up, a strong density barrier is formed which prevents vertical mixing, and dissolved nutrient
concentrations in the surface layer diminish due to phytoplankton uptake. The depth of the thermocline typically is at 15 to
20 meters in the nearfield (about half way to the sea floor). Periodic upwelling and mixing events, which occur during the
stratified period, release nutrients from below the pycnocline into the surface waters, enhancing summertime phytoplankton
productivity. As the surface layer begins to cool and sink in the fall, the water column mixes and nutrients trapped in the
bottom layer are released to the surface. This nutrient release typically produces a fall phytoplankton bloom that can exceed
the spring event in terms of chlorophyll biomass and productivity. 
The thermocline also creates a barrier to oxygen diffusion from the atmosphere. As a result, dissolved oxygen (DO)
concentrations in the bottom water typically decline throughout the stratified period. The relative magnitude of the DO
depression is dependent upon several factors: 
• initial DO concentration at the onset of stratification; 
• bottom water temperature; 
• duration of stratification; 
• availability (and quality) of carbon substrate to fuel respiration; and 
• the occurrence of periodic perturbations (mixing, horizontal advection) to the water column 
which may resupply oxygen to bottom waters. 
The rate of DO decline during the stratified period has been relatively uniform throughout the baseline monitoring years,
however, two baseline years (1994 and 1995) had significantly lower minimum DO concentrations. These two years both had
higher bottom water temperatures as well as lower initial concentrations, and appeared to have been subjected to a lesser
degree of periodic alteration of stratification. 
The conceptual models, which have evolved from the synthesis of baseline data, have supported the development and
refinement of threshold parameters to be used for post-relocation evaluations. These are discussed in the following section. 
3-2 December, 1997

3.2 Contingency Plan Trigger Parameters and Threshold Levels 
Based on the results of the Phase I baseline studies, MWRA (1997) revised the Contingency Plan and linked potential
management decisions to critical parameters. The levels applicable to the water column are summarized in Table 3-1. These
are discussed further below. Seasons are defined for the table as follows: spring, January to April; summer, May to August
and fall, September to December. 
Dissolved Oxygen Concentration and Saturation 
Aquatic animals are sensitive to the concentration of DO in the water column. Low levels of DO can have negative impacts
on marine life. Because of the importance of DO, the state has set a water quality standard that DO should not fall below 6
mg/l and 75% of saturation in Massachusetts bay. MWRA is using these standards as the basis for Caution and Warning
Levels for bottom waters in the nearfield and Stellwagen Basin. During the five year baseline period (1992 to 1996), the DO
saturation Caution or Warning level have been violated on several occasions (four times in the nearfield, five times in
Stellwagen). The applicability of the current DO threshold levels should be re-evaluated. 
Dissolved Oxygen Depletion Rate 
The average baseline DO depletion rate measured from 1992 to 1996 is about -0.026 mg/l/day. A 1.5-fold increase in the DO
depletion rate would trigger exceedance of a Caution Level. An increase could be related to increased respiration of
discharged organic matter or of algae stimulated by discharged nutrients, or to decreased ventilation of bottom waters. 
3-3 December, 1997

TABLE 3-1

Trigger Parameters for Water Column

Parameter

Rationale for Threshold.
Level:

Caution Level

‘Warning Level

Dissolved oxygen in
bottom waters of
nearfield and Stellwagen
basin (ppm or saturation
level)

* Measures potential for
hypoxia, or low DO
impacts

* Level based on
Massachusetts Water
Quality Standards

Monthly mean < 6.5
mg/l or 80% of
saturation for any one
month during
stratification (June -
Oct.)

Monthly mean < 6
mg/l or 75% of
saturation for any one
month during
stratification (June -
Oct.)

Oxygen depletion rate in

* Measures short-term and

Monthly depletion rate

Monthly depletion rate

nearfield bottom long-term rate of DO > 1.5X baseline > 2X baseline during
(mg/L/day) depletion and potential for | during stratification stratification (June -
future hypoxia (June - October), - October), -0.053
* Level based on prediction | 0.040 mg/L/day mg/L/day
in SEIS for the potential
for hypoxia
Chlorophyll in nearfield * Measures the algal Annual mean > 1.5X Annual mean > 2X
(ug/L) biomass and provides baseline, 2.80 pg/L baseline, 3.74 pg/L
indication of Seasonal mean
eutrophication state concenteration
+ Level based on exceeds 95" percentile
appreciable change from of baseline
baseline conditions distribution.
Spring: 2.71 pe/L
Summer: 2.27 pg/L
Fall: 4.44 pg/L
Paralytic shellfish * Measures the impact of New incidence None
poisoning in farfield undesirable algae
Nuisance algae in * Measures and evaluates Alexandrium None

nearfield (cells/L)

increases in undesirable
algae concentration

* Level based on change
from baseline conditions

tamarense season
mean population
densities exceeds 95"
percentile of baseline
mean.

Spring: 2.34 cells/L
Summer: 26.1 cells/L
Fall: 7.57 cells/L

3-4

December, 1997

TABLE 3-1 (Cont’d)

Trigger Parameters for Water Column

Rationale for Threshold
Parameter Level Caution Level Warning Level
Zooplankton assemblage | * Measures potential change | Nearfield assemblage
in nearfield region in zooplankton shifts from a
community structure transitional
* Level based on qualitative | community towards
indications an inshore community
(Acartia, Eurytemora,
Centropages hamatus)
with fewer
representatives from
an offshore
community (Calanus,
Pseudocalanus,
Centropages typicus,
Oithona)
Initial dilution + Measures the performance Less than that set by
of the actual outfall NPDES permit

* Level based on
comparison between
design and actual dilution

3-5

December, 1997

Chlorophyll 
Adding effluent to the marine environment could change the amounts of nutrients or the relative levels of different nutrients
so that excessive or prolonged algal blooms could occur. Chlorophyll is the most common measure of algal biomass. Since
baseline concentrations of chlorophyll-a average about 2-3 ~g/l, the Caution and Warming Levels were set at 3 to 4 ~g/l
based on peer review comments to the OMTF . The levels are well below the chlorophyll-a level of 20 g/l which is
mentioned as a eutrophication threshold in the National Oceanographic and Atmospheric Administration' s Estuarine
Eutrophication survey (NOAA 1997). In addition to annual means, seasonal thresholds for chlorophyll were developed to
better reflect the seasonal nature of algal blooms. All the discrete sampling depth samples of the nearfield from each season
are averaged to produce a seasonal mean for that year. The seasonal means for the baseline period were assumed to follow a
normal distribution such that the 95th percentile is directly related to the mean and standard deviation of the baseline seasonal
means. Actual 95th percentile values are summarized in Table 3-1. 
Nuisance and Noxious Algae 
Nuisance and noxious algae occur naturally in Massachusetts and Cape Cod Bays annually albeit in small numbers. The 1996
Peer Review Workshop recommended the use of paralytic shellfish poisoning (PSP) at shellfish beds to set red tide caution
levels. 
The nuisance algae thresholds were developed from the baseline conditions. The Caution Levels were set as the 95th
percentile of seasonal mean concentrations of the three target species of Alexandrium tamarense, Nitzchia pungens and
Phaeocystis pouchetii. 
Zooplankton 
Zooplankton community composition in inshore regions of Massachusetts Bay differs from that in offshore regions. The
nearfield region represents a transition between the two communities. The zooplankton species in inshore communities
require the high concentration of nutrients found in Boston Harbor for rnaximal growth and reproduction. One concern is that
changes in nutrient concentrations resulting from outfall relocation could result in changes in the nearfield zooplankton
community. 
Dilution 
Since all evaluations of toxic impacts depend on concentration after initial mixing, the MWRA will measure the actual
dilution of effluent by seawater around the new outfall to test predictions of effluent dilution. 
3-6 December, 1997

3.3 Phase II Monitoring Plan 
Because the post-discharge monitoring results will be compared to pre-discharge results, it is important that the methods used
to collect the data are comparable and consistent. Thus the Phase II monitoring plan is similar to the Phase I monitoring plan.
The monitoring includes 17 surveys per year focussed on the nearfield area (see Figures 3-1 for station locations) and 6
surveys per year covering the farfield area with stations in Massachusetts and Cape Cod Bays and Boston Harbor (see Figure
3-2). Each station has a designated set of analyses performed on samples collected at various depths (see Tables 3-2 and 3-3
for nearfield and farfield station designations and Table 3-4 for definition of analysis groups). Stations F23, NO4 and N18 are
actually D+P+R stations, but historically displayed as D+P stations in Figure 3-1 for convenience of representation. Further
details are provided below. 
3.3.1 Nearfield 
Water Quality and Hydrography 
Measurement:
dissolved 
Dissolved ammonium, nitrate, nitrite, phosphate, and silicate; in situ temperature, salinity,
oxygen, chlorophyll fluorescence, transmissometry , irradiance, depth of sensors, and altitude of
sensors above seafloor . 
Location: Discrete samples for nutrients at 21 stations (Figure 3-1) along rectangular cruise tracks at five
depths: one surface sample, two rnid-depth samples that span the pycnocline when it exists, one
rnid-depth sample at the chlorophyll maxima, and one bottom sample. Continuous vertical profiles
of hydrographic measurements will be taken from surface to within 5 m of the bottom at each
station. 
Frequency: Seventeen surveys per year during weeks number 6, 9, 12, 14, 17, 20, 25, 27, 30, 32,
34, 36, 39, 41, 44, 48, and 51. 
Biology and Productivity 
Measurement: Dissolved organic carbon, nitrogen, and phosphorus; particulate carbon, nitrogen, and phosphorus;
total suspended solids; discrete chlorophyll-a (filtered samples) along with phaeopigments;
dissolved oxygen; in situ relative fluorescence. 
Location: Discrete samples at 7 stations (type A or D in Figure 3-1) at 2 to 5 depths (depending on the
parameter) as presented in Tables 3-2 and 3-4. 
3-7 December, 1997

42°30700"

42925°00"

42°20°00"

4asior”

"40 13500"
‘SCALE 1:220000 LEGEND
5 ° 5 No ing Locutioa Name
= ADE ‘Sampling Type
FIGURE 3-1
Nearfield Stations.

Arrows Denote Potential Survey Track.

3-8 December, 1997

42°30°00"

FIGURE 3-2
Farfield Stations.
Arrows Denote Potential Survey Track.

3-9 December, 1997

Ol-€

266 | ‘“sequieseq

Analysis Group for Each Station and Depth, Nearfield Survey

TABLE 3-2

Station | Not | Noz | Nos

Name

Station A|E|.£

_Type
Nearfield Stations
Surface G3 | G8 | G8 | Gi+P+R | G8 | G8 | G3 | Gs | cs] @ G8 | G8 | Gs | G8 | Gs | G3 | Gs | Gi+P+R]| G8 | G3 | Gs
‘Mid-surface GS | G8 | G8 G3+P. G8 | G8 | GS | Gs | Gs | os G8 | G8 | G8 | G8 | Gs | Gs | Gs GS+P G8 | GS | G8
Middle G3 | G8 | G8 | G2+P+R | G8 | G8 | G3 | Gs | Gs | G | cs | cs | cs | cs | cs | cs | as | az+P+R| cs | G3 | cs
Mid-bottom GS | G8 | G8 GS+P G8 | G8 | Gs | Gs | Gs | Gs G8 | G8 | G8 | G8 | Gs | Gs | Gs G5+P Gs | GS | G8
Bottom G3 | G8 | G8 | G3+P+R | G8 | G8} G3 | G8} Gs} G@ G8 | G8 | G8 | G8 | G8 | G3 | G8 | G3+P+R} G8 | G3 | Gs

LL-€

266} “Wequieseq

TABLE 3-3

Analysis Group for Each Station and Depth, Farfield Survey

o> Station: Fo

Name

Stattor D

‘Type
Farfield Stations
Surface ‘| at | at | o8 | cs | ot | os | os | a7 | at | cs | os | os G8 | G8 GRR G8. | GI+PeR | GI GI G8
‘Mid-surface GS | G5 | G8 | G8 | Gs | G8 | Gs | G7 | Gs | Gs | Gs | Gs | Gs | Gs a7 G8 GS+P Gs | GS 8
Mid-depth G2 | G2 | G8 | G8 | G2 | G8 | G8 | G7 | G2 | Gs | G8 | Gs | cs | cs G74#R | G8 | G2P#R | G2} G2 G8
Mid-bottom GS | GS | GB | G8 | GS | G8 | G8 | G7 | Gs | Gs | Gs | Gs | Gs | Gs a G8 GS+P Gs | GS G8
Bottom G3 | G3 | G8 | G8 | G3 | G8 | G8 | G7 | G3 | Gs | Gs | Gs | Gs | Gs GHR | G8 | G3+PHR | G3 icy Gs

ol-€

266 | ‘“sequie0eq

TABLE 3-4

Chemical and Biological Analysis Performed in Each Analysis Group

Dissolved Inorganic Nutrients

Dissolved Organic Carbon

Total Dissolved N & P

Particulate C & N

Particulate P

Biogenic Silica

Chlorophyll & Phaeopigments

Total Suspended Solids

mM] mp ee] x] os] oe] me] oe do

Dissolved Oxygen

Urea

All Phytoplankton

mM] Mp KT | wp ep oe] mw] od oe | x] x

Screened Phytoplankton

Ce ec de oe re

Zooplankton

Areal Productivity

Respiration

Frequency: Seventeen surveys per year during weeks number 6, 9, 12, 14, 17, 20, 25, 27, 30,
32, 34, 36, 39, 41, 44, 48, and 51. 
Measurement: Phytoplankton and zooplankton identification and enumeration, urea, 14 C primary 
productivity, and respiration. 
Location: Discrete samples at 2 stations (type D Figure 3-1) at two depths for phytoplankton
and urea (surface and mid-depth), zooplankton by net tow. Primary productivity and
respiration measurements at stations N04 and N18. 
Frequency: Seventeen surveys per year during weeks number 6,9, 12, 14, 17, 20,25, 27, 30,
32, 34, 36, 39,41,44,48, and 51. 
Dilution 
The dilution performance of the outfall will be evaluated and compared with design and model results. Revised dilution ratios
will be used to update the NPDES permit and allow for better fate and transport evaluation of contaminants of concern. 
Measurement: Continuous monitoring of sewage tracers such as salinity and dye (rhodamine WT
added to the effluent for the survey). Hydrographic measurements to establish the current
and density stratification field. The details of these measurements remain to be developed
along with the workplan. 
Location: Rectangular tracks in a twenty five square km area centered on the middle of the future outfa1l. 
Frequency : Four surveys after the outfall becomes operational spread out over the year to
represent various seasons. Measurements will be carried out in a time frame to
cover typical tidal variations. 
3.3.2 Farfield 
Data is collected from far-field stations to establish reference conditions and to determine if a region-wide trend is occurring. 
Water Quality and Hydrography 
Measurement: Dissolved ammonium, nitrate, nitrite, phosphate, and silicate; in situ temperature,
salinity, dissolved oxygen, chlorophyll fluorescence, transmissometry, irradiance,
depth of sensors, and altitude of sensors above seafloor. 
Location: Discrete samples for nutrients at 26 stations (Figure 3-2) at five depths: one
surface sample, two mid-depth samples that span the pycnocline when it exists,
one mid-depth sample at the chlorophyll maxima, and one bottom sample (three
depths at the shallower harbor stations). Continuous vertical profiles of 
hydrographic measurements will be taken from surface to within 5 m of the
bottom at each station. 
Frequency: Six surveys per year during weeks number 6, 9, 14, 25, 34, and 41. 
3-13 December, 1997

Biology and Productivity 
Measurement: Dissolved organic carbon, nitrogen, and phosphorus; particulate carbon, nitrogen,
and phosphorus; total suspended solids; discrete chlorophyll-a (filtered samples)
along with phaeopigments; dissolved oxygen. 
Location: Discrete samples at 11 stations (type G or D in Figure 3-2) at 3 to 5 depths
(depending on the parameter) as presented in Tables 3-3 and 3-4. 
Frequency: Six surveys per year during weeks number 6, 9, 14, 25, 34, and 41. 
Measurement: Phytoplankton and zooplankton identification and enumeration, urea, 14 C primary
productivity, and respiration. 
Location: Discrete samples at 9 stations (type D, Figure 3-2) at two depths
for phytoplankton and urea (surface and mid-depth), zooplankton by net tow.
Primary productivity measurements at station F23 (Figure 3-2). Respiration
measurements at stations FI9 and F23. 
Frequency: Six surveys per year during weeks number 6, 9, 14, 25, 34, and 41. 
Paralytic shellfish poisoning 
The monitoring of PSP in shellfish beds is managed by Massachusetts Department of Public Health. 
3.3.3 Special Studies 
Water Circulation, Particle Fate and Plume Tracking 
An understanding of how the effluent would be transported away from the outfall area after initial dilution is necessary for an
assessment of the risk associated with various contaminants dissolved in the effluent . An understanding of how particles
would be transported, coagulate and settle is also important because many toxic contaminants tend to be sorbed on the
particulate phase. The MWRA has entered into an cooperative agreement with the U.S. Geological Survey (USGS) since
1991 to perform some of these studies. The USGS maintains a moored array near the future outfall site for continuous
monitoring of currents, conductivity (salinity), temperature, fluorescence (chlorophyll), and transmittance (turbidity). In
addition, a sediment trap is employed at the mooring. Additional moorings could be employed, along with the use of drogues
and drifters to ascertain long term average transport and sedimentation patterns. At a minimum the current USGS mooring at
the outfall site will be maintained. 
Plume tracking surveys are performed to determine the location and chemical and biological characteristics of the effluent
discharge plume leaving the outfall and mixing with ambient waters. Physical characteristics will also be monitored.
Continuous sensor measurements of salinity (conductivity), temperature, DO, chlorophyll (fluorescence), TSS (via optical
beam transmittance) and perhaps acoustic techniques will be performed along with discrete water sample measurements (for
calibration). 
3-14 December, 1997

Remote Sensing 
Remote sensing via satellite imagery offers the opportunity to evaluate spatial variations in the system, and to provide
information on changes within the system which occur between monitoring surveys. Parameters which are available from
satellite imagery include sea surface temperature and chlorophyll (e.g. Ocean Color and Temperature Scanner, OCTS). This
imagery is available in processed form off the Internet; the monitoring program will access this imagery and use it in the
synthesis of water column monitoring results. 
Primary productivity, Benthic nutrient flux, denitrification and oxygen demand 
The relation between nutrient level, chlorophyll-a and primary production, as well as its impact on dissolved oxygen, are an
important concern. Alternate methods for measuring primary productivity more efficiently are being explored. 
An understanding of benthic nutrient flux is necessary for calculating a mass balance of nutrients, especially for nitrogen. The
bottom water depletion of dissolved oxygen is due to both water borne oxygen demands (cBOD, respiration and decay of
planktonic material) and sediment bound oxygen demand. A knowledge of both is necessary to understand the DO depletion
rate. This is discussed in the Benthic Monitoring Section. 
Modeling 
It has been recommended that the Bays Eutrophication Model (BEM) should be used to see whether DO conditions in 1992
to 1995 could be reproduced, and to be used for assessing future conditions. The original framework was ambitious in its
design, with the ultimate goal to establish detailed cause and effect relations between nutrients, plankton growth and the
subsequent impact on dissolved oxygen. The ability of such models for making predictions should be realistically assessed
and re-evaluated, in particular whether deterministic models are applicable to complex environmental systems. 
Shoreline Pathogen Monitoring 
It was recommended that shellfish bed monitoring for pathogens be integrated into the overall monitoring program (in
conjunction with the Division of Marine Fisheries). This recommendation is under development. 
3.4 Data Evaluation and Comparison to Thresholds 
Post-discharge monitoring of the water column is similar to the baseline monitoring. The suite of measurements will provide
all the necessary information for threshold comparisons (chlorophyll, DO, phytoplankton and zooplankton). Other
measurements are made which serve as supporting information for interpreting the threshold parameters. Furthermore, the
sampling provides data suitable for input to the Bays Eutrophication Model. 
Dissolved Oxygen Concentration and Saturation 
The concentration of dissolved oxygen is bottom waters of individual samples in the nearfield and Stellwagen basin has on
occasion gone below the threshold values of 6 mg/l and 75% saturation during the baseline monitoring period. The factors
that determine minimum DO are 1) the initial DO concentration before it starts to decline; 2) water temperature; 3) the total
time of decline and; 4) the occurrence of mixing events. These items are closely linked to the onset stratification and the
tinting of the fall overturn. Violation of the DO threshold during the baseline period indicates that low DO excursions of
bottom waters in Massachusetts Bay occur naturally. This issue will require consideration during evaluation of post-discharge
DO data. 
3-15 December, 1997

Dissolved Oxvgen Depletion Rate 
The DO depletion rate in bottom waters of the Nearfield and in Stellwagen Basin are of special concern. The numerous DO
measurements over time will allow for calculations of the DO depletion rate, which will then be compared to the threshold
levels. Standard linear regression of DO concentration versus time will be performed with collection data to calculate the DO
depletion rate. This will be compared directly with the mean DO depletion rate measured in the baseline period (with the
appropriate multipliers, e.g. 1.5 x for Caution Level). 
Chlorophyll 
Chlorophyll concentrations will be available from the nearfield and farfield surveys. These chlorophyll measurements will be
aggregated by time and space to provide suitable values for comparison to the threshold levels. For example, mean seasonal
chlorophyll concentrations in surface waters in the nearfield will be calculated and compared to the 95th percentile of the
seasonal average concentration from the baseline period. Annual average chlorophyll from ship surveys in the nearfield area
will also be calculated and compared to the threshold values. Additional measurements of chlorophyll are available from
satellite imagery and from an instrument deployed on the long term USGS Mooring near the future outfall site. 
Nuisance and Noxious Algae 
Water samples are collected for identification and enumeration of phytoplankton. Special attention will be given to the three
target species Alexandrium tamarense, Nitzchia pungens and Phaeocystis pouchetii. The Caution Level relates to the 95th
percentile of the seasonal mean concentrations. 
Zooplankton 
The phytoplankton net tows described above will also provide samples for zooplankton identification and enumeration. These
cell data will allow for a characterization of the community structure in both the nearfield and the farfield. This will be used
to determine whether the nearfield region is becoming more like the inshore region rather its present status of being a
transition between inshore and offshore regions. 
Dilution 
The special dilution studies will provide the information necessary for calculating the actual outfall dilution and comparison
against designed dilutions. This information could be used along with effluent monitoring information for permit evaluation.
The available effluent loading information can be used along with the measured dilution and plume tracking studies to further
evaluate the long-term fate and transport of various parameters of concern (e.g. nutrients). 
Data Reporting 
MWRA will develop a reporting schedule with the objective to expedite communication of threshold parameter results. For
the water column monitoring, these include chlorophyll, oxygen, and nuisance phytoplankton species. Both chlorophyll and
oxygen are monitored by in situ sensors which are post-calibrated using analytical results from discrete samples. The
expedited reporting for these parameters will be: 
• 1 week turnaround time (TAT) after each survey for a tabular summary of preliminary sensor un-calibrated results (e.g.
Temperature, Salinity, DO, fluorescence, etc), to be accompanied by any supporting information regarding sensor offset,
drift, or maintenance activity (membrane change) which may affect relative sensor output; 
3-16 December, 1997

• 3 week TAT for a tabular summary of DO and chlorophyll analytical results to confirm preliminary sensor results, which
will coincide with submittal of the survey report: 
• two months (following last survey of each period) for periodic data reports, which are submitted five times per year. 
MWRA will also require expedited reporting for nuisance phytoplankton taxa. Since the seasonal occurrences of the three
taxa which have been identified as nuisance species (Phaeocystis pouchetii, Alexandrium tamarense, and Pseudo-nitzschia
multiseries) vary widely, and together encompass almost the entire annual monitoring period, this reporting will be
performed on a routine basis for each survey. 
To achieve the objective of nuisance phytoplankton reporting, an extra screened phytoplankton sample will be collected at
nearfield station N18 during each of the 17 nearfield surveys. This sample will be collected at the chlorophyll maxiinum
depth. This approach will provide the best representation of the potential presence of nuisance taxa in the photic zone. 
The extra screened sample will be qualitatively examined immediately upon receipt by the plankton subcontractor. The
subcontractor will determine whether the nuisance taxa are present in the sample and estimate their density .In addition, the
subcontractor will identify the dominant form of other taxa present. These results will be communicated with the plankton
task manager, and, in the event that nuisance species are encountered, forward the results to the MWRA Water Column Task
Manager. The results will also be included with the survey summary provided within one week of the survey's completion.
Complete reporting of quantitative taxonomic analyses will be submitted within two months (following the last survey of
each period) in the periodic plankton reports submitted five times per year. 
3-17 December, 1997

4.0 BENTHIC MONITORING 
One of the primary concerns with wastewater discharge into marine environments is organic enrichment of the seafloor,
resulting in poorly oxygenated muds supporting impoverished communities of opportunistic colonizers which are pollution
tolerant. Another concern is the build-up of toxic contaminants in the sediments that can be bioaccumulated by benthic
organisms and eventually fish and shellfish that are commercially important. These concerns are justified in terms of sludge
discharge (such as Boston Harbor prior to 1992 or the New York Bight) or primary treated effluent discharge (such as Los
Angeles Hyperion plant prior to upgrade to secondary treatment) where particle loads are still relatively high. Effective
dilution of the new outfall in Massachusetts Bay will help ensure only minor impact on the benthos within a relatively narrow
zone around the diffuser. 
4.1 Overview of Phase I Baseline Studies 
The Benthic Monitoring Program was initiated in 1992 to focus on soft sediments near the site of the new outfal1 (the
nearfield) with its line of 55 diffusers as well as selected sentinel stations in various parts of Massachusetts Bay and Cape
Cod Bay (the farfield). It initially included 10 special stations at farfield locations sampled for biology in May 1992 as part of
a USGS/MWRA survey, 20 stations in the nearfield sampled in August 1992, and 12 stations in the farfield also sampled in
August 1992. However, achieving a good monitoring design for the nearfield area has been difficult due to the heterogeneity
of habitats and paucity of muddy sites, and the sampling protocol was modified several times to find the best approach.
Regardless of these changes, the baseline program should permit a full assessment of natural processes in the nearfield prior
to the initiation of sewage disposal operations in 1998. Based upon the data through 1994, the nearfield was redefined for
benthic monitoring as a 2-krn area around the outfall in which changes are most likely to occur once the outfall goes on line.
The remainder of the original nearfield, and some of the nearshore farfield stations, have .since been termed midfield (see
Table 4-1). Stations FF10, FF12 and FF13 are now midfield stations, but their designations have not been changed. See
Figures 4-1, 4-2 for the location of these stations. 
Twice since 1992, the spatial array of stations sampled with grab samples was integrated with the sediment profile camera to
allow mapping of physical and biological patterns in Massachusetts Bay. 
Important Findings 
In Western Massachusetts Bay, including the vicinity of the future effluent outfall, relic glacial topography and infrequent
physical disturbances control sediment deposition in the near and midfield. This sedimentary regime results in a complex
mosaic of sediment types in the mid- and nearfield, with small 
4-1 December, 1997

TABLE 4-1

Revised Station Grouping after Coats (1995)

+. .Station-Grouping Distance from: Outfall ~ Stations 3
nearfield 0-2 km NF13, NF14, NF15, NF17, NF18,
(diffuser-induced changes are NRFI9, NF23, NF24
expected)
midfield 2-8 km MF2, MF4, MFS5, MF7, MF8, MF9,
(diffuser-induced changes are less MFIO, MF12, MF16, MF20, MF21,
likely) MF22, FF10, FF12, FF13
farfield >8 km FFIA, FF4, FFS, FF6, FF7, FF9, FF11,
(diffuser-induced changes are FF14
highly unlikely)

‘The original grouping by Coats for the midfield was 2-7 kam from the outfall, this has been modified to 2-8 km in this plan.

4-2

December, 1997

70°54' 70°52' 70°50' 70°48' 
FIGURE 4-1 
Nearfield and Midfield Soft Bottom Stations. 
4-3 December, 1997

42°30'
42"15'
42°00'
41°45' 
71°00' 70°45' 70°30' 70°15' 70 ° 00' 
FIGURE 4-2 
Station Locations for Grab Samples, Farfield. 
4-4 December, 1997

patches, about 100 to 1,000 m in diameter, of muddy depositional sediments interspersed with sandier patches and separated
by expanses of erosional gravels, cobbles, and boulder-strewn submerged drumlins. 
The presence of layered sediments, such as sand over mud, as well as changes in surficial grain size at some sites between
years, has suggested active, storm-induced sediment transport. 
The structure of the benthic communities in the near- and midfield is largely determined by sediment grain size. These
structures have been observed in the area since inception of this program, with slight changes reflecting the shifting of
sediments. Benthic community structure in the farfield is mostly influenced by water depth and also by location
(Massachusetts Bay versus Cape Cod Bay). Species diversity and species composition have been varying over time, and
likely have been a reflection of natural events such as larval settlement. The dominant benthic species at the future outfall site
in 1995 was also abundant in 1987, but not in 1992 through 1994. 
In 1994 and again in 1995, serni-quantitative video surveys were conducted in the hard-bottom areas adjacent to the new
outfall to complement the soft-bottom studies. These two surveys have shown that location on the drumlins, depth.
substratum type, and habitat relief all appear to playa role in determining the structure of benthic communities inhabiting
hard-bottom areas in the vicinity of the future outfall. Benthic communities inhabiting drumlin tops are dominated by red
algae, whereas the drumlin flanks and topographic lows are characterized by encrusting or attached fauna. 
In 1995, organic contaminant concentrations in sediments were generally low and did not exceed any of the thresholds.
Nearfield mean metal concentrations for all trace metals were below the ER-M sediment criteria. Mercury concentrations
were relatively high at two individual stations, with the one at NF24 (1.69 ~g/g) exceeding the ER-M value of 0.71 ~g/g. 
4.2 Contingency Plan Trigger Parameters and Threshold Levels 
Based on the results of the Phase I Baseline Monitoring results, MWRA (1997) revised the Contingency Plan and linked
potential management decisions to critical parameters. The levels applicable to the benthic environment are summarized in
Table 4-2. 
4-5 December, 1997

TABLE 4-2

Trigger Parameters for the Benthic Environment

Rationale for Threshold
Parameter Parameters Caution Level Warning Level
Redox potential discontinuity | - Measures decrease in RPD depth declines by
in nearfield sediments oxygen content in sediment | half. The threshold
environment value is under
development, average
is about 3.5 cm in
1995
Toxic contaminants in - Measures potential for toxic | 90% of EPA sediment
nearfield sediments effects on benthic marine criteria where
life available.
- Thresholds based on 90% of NOAA ER-M
national sediment quality or PEL, whichever is
criteria lower for a given
contaminant
Community structure - Provides measure of Species diversity,
(diversity, species benthic community health composition, and
composition, and species relative abundance
abundance) in outfall patterns measured in
midfield area the mid-field
appreciably depart
from those measured
during the baseline
monitoring period,
after factoring out the
effect of storms on
sediment texture.
Specific diversity
threshold values are
being developed.
Species composition in the - indicates changes in 25% shift of 50% shift of
midfield (2-8 km from sedimentary environment community toward community
outfall): appearance of opportunists. toward
opportunistic species not opportunist’s

encountered during baseline
monitoring

December, 1997

4.3 Phase II Monitoring Plan 
Soft-bottom benthos in the nearfield and farfield 
Measurements: Benthic species composition and abundance as retained on 0.3 mrn sieves; chemical constituents
including PAHS, LABS, PCBS, pesticides, metals, TOC; sediment grain size; Clostridium
perfringens spore counts in the 0 to 2 cm depth fraction; and sediment profile images for
measurement of RPD depth, and other physical and biological parameters. 
Replication: In order to permit statistical comparisons between stations and years,. replication has been built into the
sampling design. For the benthic biology samples, three replicate 0.04 m2 grab samples are collected at each
of the farfield stations, nearfield stations NF17 and NF24 and midfield stations MF12, FF10, FF12, and
FF13. The mix of replicated and non-replicated samples in the nearfield and midfield brings the total
number of samples to 12 and 23 in each of these areas, respectively. According to Coats (1995), these 12
replicates can be treated as independent observations to provide sufficient statistical power to detect smaller
scale changes in benthic parameters (e.g., 8% change in the Shannon-Wiener index, H' in the pooled
midfield stations). 
Location: Eight stations in the nearfield and 15 stations in the midfield. Eight stations in the farfield. 
Frequency : One sampling per year (August) for all parameters. The OMTF has indicated that the measurement
frequency for contaminants should be revisited after approximately two years of discharge monitoring data
are available, and that a long-term sediment contaminant sampling frequency on the order of every 3-5 years
should then be appropriate except organic and metal constituents which are to be sampled at 2-3 year
intervals depending upon recommendation of the OMTF. 
Special study of hard-bottom benthos in the nearfield 
Measurements: Benthic hard-bottom species composition as determined by 35-mm photography and video analysis;
topography and sediment cover. 
Location: Eight transacts along drumlins and other topographic features in the vicinity of the outfall to a distance of 2
mi (=3.2 km) north and south. See Figure 4-3 for suggested transect locations. 
Frequency: One sampling per year (June to August timeframe ). 
Special studies on benthic nutrient flux 
Benthic flux measurements have provided important information on bounds of the sediment denitrification rate, as well as the
contribution of sediment oxygen demand to overall bottom water DO depletion rates. 
4-7 December, 1997

70°49" 70°48" 70°47' 70°46'

42°24 42°24
42°23 42°23"
42°22" 42°22!
70°49" 70°48" 70°47" 70°46'
@
FIGURE 4-3

Transect locations for nearfield hard-bottom video survey.
Open circles are 1995 stations; filled circles are 1996 stations.

’

4-8 December, 1997

4.4 
Measurements: Temperature, salinity and DO of the bottom water at each station when surveyed. Two cores per station will 
be incubated and measured for ammonia, nitrate & nitrite, urea, phosphate, silica and DO in the overlying
water of those two cores per station every 2-8 hours. Total carbon dioxide will be measured at the beginning
and end of the incubation. In addition, undisturbed sediment cores will be obtained from each station and
measured for profiles of porewater ammonia, nitrate & nitrite, urea, phosphate, silicate, dissolved sulfides,
pH, alkalinity and redox potential in at least 10 depths per station. Surficial sediments from each station will
also be analyzed for total organic carbon, total nitrogen and grain size. 
Location: See Figure 4-4 for location of benthic flux sampling locations. 
Frequency: Four surveys each year during March, May, July, August and October. 
Special studies on sediment transport 
In addition, the USGS maintains an active research program to study the transport of sediments in Massachusetts Bay. 
Data Evaluation and Comparison to Thresholds 
Coats (1995) developed a complex multivariate approach to test for change in the nearfield benthic communities. He also
demonstrated that pooling of replicated and non replicated contaminant data within the nearfield and midfield provides
sufficient statistical power to detect any increases in contaminant concentration well before concentrations of concern are
reached. However, some caution needs to be exercised because there may be a bias in pooling multiple samples from one site
with non-replicated samples that are more widely distributed among sediment types. 
The multivariate analysis developed by Coats (1995) for detecting change in nearfield and midfield benthic communities
from baseline variation shows promise as a sensitive indicator of change in species diversity and composition, but suffers
from shortcomings that limit its application as a rapid response threshold. First, it is theoretically quite complicated, and is
fully interpretable only to specialists in numerical ecology. Second, before the requisite analyses can be run, extensive checks
must be carried out to ensure full comparability between a year's species identifications and the baseline data set. Occasional
changes in the understanding of individual groups of organisms can lead to what were formerly thought to be 2 species
lumped into a single group, or to the reverse situation, with a single taxon split into 2 new species. Multivariate analyses
similar to those developed by Coats (1995) are particularly sensitive to the effects of this kind of change. Reconciling the
implications of such changes to a multi-year data set can often required weeks, as appropriate taxonomic authorities must
sometimes be consulted. 
4-9 December, 1997

42°30'
42°25'
42°20'
42°15' 
71°00' 70°55' 70°50' 70°45' 70°40' 70°35' 
FIGURE 4-4 
Benthic Nutrient Flux Sampling Locations. 
4-10 December, 1997

Taken together, these shortcomings suggest that multivariate analyses similar to or derived from that of Coats (1995) are best
used as confirmatory and/or interpretive analyses, with initial threshold testing carried out using parameters more readily
understood by non-specialists, and less sensitive to minor changes in species identifications. 
Soft-bottom Benthos/Benthic Diversity 
A suite of parameters was developed by ecologists in the past 50 years to summarize patterns of species richness, species
diversity, abundance, and dominance. However, to date none have shown broad applicability as stand-alone indicators of
change in sediment communities. Investigations to refine rapid response trigger parameters for threshold testing are ongoing,
and revisions to the parameters described below will be submitted for OM1F review in early Spring 1998. 
Data generated by these analyses will be compared with the baseline results to ensure that no appreciable impact has
occurred. In the case of the soft-bottom benthos, the nearfield has been divided into a nearfield that is within 2 km of the
discharge and a midfield that extends outside of the 2 km discharge radius to a distance of 8 km. An additional three farfield
stations (each with three replicates) are also located in the midfield area. 
Water quality model predictions of organic carbon deposition to the seafloor (Hydroqual and Normandeau, 1995) suggest
that some faunal changes are likely within 2 km of the outfall, but not in the midfield. Therefore, while changes in near-field
stations will be monitored, trigger levels apply to the midfield stations outside the 2-km boundary. 
Currently, the most promising diversity parameter for threshold testing appears to be species diversity calculated with the
Hurlbert rarefaction method at a sample size of 100 individuals. Ongoing threshold development efforts include deriving
related measures of species evenness. Other diversity metrics, for example, the Shannon Wiener information function (H')
and Pielou's evenness (J' ) will continue to be calculated, but will probably not be primary thresholds. 
Measures of species diversity cannot stand alone as indicators of community change, as the identities of the species present
plays no role in their calculation. In other words, identical diversities might be calculated from 2 samples that share no
species. Since changes in the types of species found in sediments (known as a community's composition) are frequent
responses to pollution, diversity thresholds need to be coupled with a community composition threshold. 
The establishment of trigger parameters for changes in species composition is difficult because there could be a range of
natural changes possible depending upon the degree of perturbation on the community. 
Caution levels might include the appearance of species in dominance lists that were not previously encountered at those
stations or groups of stations. Warning levels might include the total dominance of these species coupled with a
corresponding decrease in species diversity .For example, the common estuarine polychaete Polydora cornuta is a common
indicator species in Boston Harbor, yet is rare in Massachusetts Bay. The appearance of P. cornuta at a midfield station
might be interpreted as a shift to a stressed community because the species is normally found in situations where the RPD is
shallow, species diversity is low, and organic loading is high. Likewise, the appearance of dense assemblage of amphipods,
such as now occur in Boston Harbor, might be indicative of an altered sedimentary regime. Any such changes in faunal
composition will need to be closely compared with the species diversity and sedimentary data in order to explain and
understand the processes that have led to change. Suggested Caution (20%) and Warning (50%) Levels are presented in
Table 4-2. 
4-11 December, 1997

The hard-bottom study was established by OM1F as a supplemental study, not intended to duplicate the intensity (and
ultimately the sensitivity) of the soft-bottom monitoring. Therefore, no thresholds have been established for this component.
The hard-bottom program will focus on interpreting effects of the discharge within the outfall nearfield. Monitoring results
(consisting of video and 35-mm slides) in the different habitat types will be compared against the baseline results. The video
tapes will be viewed to provide information on the uniformity of the environment. Large, clearly identifiable organisms will
be enumerated. Slides will be projected and analyzed for sea-floor characteristics and organisms. Most recognizable taxa will
be recorded, counted and normalized to mean number of individuals per slide. Data from each waypoint will be pooled and
examined by hierarchical classification. This consists of a pairwise comparison of the species composition of all waypoints
using the percent similarity coefficient. Changes in species composition and increased sediment drape on the rocks may be
evidence of impact. See Figure 4-3 for the location of the hard-bottom survey transects. 
Toxic Chemicals in Sediments 
The very low contaminant concentrations found in secondary effluent means that loading of contaminants from the future
discharge will be small compared to the amounts already present in the environment (Mitchell, et al., 1997). Therefore,
sediment-bound contaminant concentrations are not expected to change over short time scales (months to a year) as a result
of the discharge, although moderate short-term fluctuations have been documented associated with major storm events
(Bothner, et al., 1993). Nonetheless, concerns over short-term build-up of contaminants were sufficient for the OMTF to
determine that during the first 2 to 3 years after discharge begin, all nearfield, midfield, and farfield stations should be
sampled annually, and that a small, 3 to 4 station 2-year special study focussing on even shorter time scales (every 4 months)
be designed to supplement the annual sampling and the USGS sediment transport study. 
The OMTF has indicated that the measurement frequency for contaminants should be revisited after approximately two years
of discharge monitoring data are available, and that a long-term sediment contaminant sampling frequency on the order of
every 3 to 5 years should then be appropriate. 
An OMTF subcommittee that evaluated the sediment contaminant program in April 1997 recommended that previously
suggested contaminant thresholds (see, for example, MWRA, 1995) be modified as follows: Where EP A has recommended
draft sediment quality criteria, a Caution threshold will be established at 90% of that level. Where criteria are not available,
Caution Levels will be established for individual compounds at either 90% of the Effects Range-Medium Levels published in
Long et al., (1995) or at the Probable Effects Levels established in MacDonald (1993). The subcommittee recommended that
no Warning Level thresholds be established at this time. 
The subcommittee recommended against the addition of sediment toxicity bioassays to the routine monitoring, however
suggesting that such measurements may be useful supplementary measurements if contaminant thresholds are reached. A
recent study in the area demonstrated no clear link between contaminant concentrations, measurements of sediment toxicity ,
and the apparent health of the benthic communities sampled (Hyland and Costa, 1995). 
Sediment Profile Image Analysis/RPD Depth 
Sediment profile image analysis will provide an accurate estimate of the apparent depth of the redox potential discontinuity
level (RPD) in sediments. The SPI camera also provides detail of surface benthic boundary features, sediment layering, grain
size, methane, and various biological parameters including bioturbation and presence/absence of tube mats. An
organism/sediment index can be generated, that when coupled with dissolved oxygen and Clostridium pe1fringens data can
estimate the relative health of the seabed. A reduction in the depth of the RPD is an indication that water column dissolved
oxygen is decreasing. Shallow RPDs will result in hydrogen sulfide production and possibly methane production. Deep RPDs 
4-12 December, 1997

are indicative of healthy conditions. The 1995 RPD by sediment profile image studies showed a range of 1.8 cm to greater
than 6.2 cm, with a mean value of 3.5 cm. 
In a monitoring program where short-term results may be crucial for identifying problems with sediment quality, the SPI
camera offers the possibility of rapid data return. If necessary, the 35mm slides can be examined with a "quick-look" method
that can be used to provide evidence of Caution Levels within 24 hours of sampling. 
4-13 December, 1997

5.0 FISH AND SHELLFISH MONITORING 
MWRA has continued to conduct a biomonitoring program for fish and shellfish, which supports evaluation of the future
effluent outfall in Massachusetts Bay. The goal of the biomonitoring program is to obtain baseline data that may be used to
assess the potential environmental impact (i.e., protection of human health and biological resources) of the effluent discharge
on Massachusetts Bay, and to evaluate the facility's compliance with threshold values. 
The specific objective of the fish and shellfish monitoring program to date has been to define the baseline condition of three
indicator species: winter flounder ( Pleuronectes americanus ), Northern lobster ( Homarus americanus), and blue mussel
( Mytilus edulis). These three indicator species are used to evaluate environmental impacts to: bottom-dwelling fish (winter
flounder); surface-dwelling macroinvertebrates (lobster); and water-column filter-feeder (blue mussel). Body burdens of
certain pesticides (DDT , aldrin/dieldrin, chlordane, heptachlor, etc.), PCBS, lead, and mercury were compared to FDA
Action limits and monitoring program warning limits to evaluate potential risk or trends. Finally, the results were evaluated
for their ability to answer the underlying monitoring hypotheses. 
5.1 Overview of Phase I Baseline Studies 
Earlier bioaccumulation studies by MWRA have utilized blue mussels and analyzed for PAHS, selected pesticides, PCBS,
lead, copper and zinc. The current baseline fish and shellfish monitoring program added more metals, mercury in particular
(see Table 5-1). As shown on Figure 5-1, specimens were collected from sites in Boston Harbor (Deer Island Plats, off 
Discovery ), Massachusetts Bay (Future Outfall Site, Nantasket Beach, Broad Sound), and Eastern Cape Cod Bay. Baseline
conditions were characterized in terms of biological parameters (length, weight, biological condition); the presence/absence
of disease (both internal and external); and concentrations of organic and inorganic compounds in various tissues. These
tissues included: for the winter flounder -liver and filet; for the northern lobster -hepatopancreas and tail meat; and for the
blue mussel -soft tissue. The monitored parameters were examined for spatial trends between stations and interannual
variations from previous monitoring data. Since the mussels are incubated in situ in caged arrays, the predeployment mussels
serve as experimental controls. Table 5-1 summarizes the chemical analyses performed for fish and shellfish. 
Gross deformities, parasites or visually apparent diseases are noted for both collected flounder and lobster. In addition,
histological measurements in flounders are used (in particular, liver lesions) as a measure of their general health, which in
turn reflect on the ecological status of their general environs. 
5-1 December, 1997

TABLE 5-1

Chemistry Analyses for Fish and Shellfish Monitoring

‘Organism (Type of Samples) ‘Parameters
Flounder 9 or 15 composites Mercury
(fillet)* PCB
Chlorinated pesticides
Lipids
Flounder 9 or 15 composites Trace metals
(liver)* PCB 5
PAH :
Chlorinated pesticides
Lipids
Lobster 9 composites (meat) Mercury
PCB
Chlorinated pesticides
Lipids
Lobster 9 composites Trace metals
(hepatopancreas) PCB
PAH
Chlorinated pesticides
Lipids
Mussel 20 composites (soft Mercury
meat) Lead

5-2

December, 1997

FIGURE 5-1 
Sampling Stations for Winter Flounder, Lobster and Mussels during 1996 . 
Important Findings 
The baseline fish and shellfish monitoring program has shown that contaminant concentrations are generally higher in
flounder from Boston Harbor than from the future outfall site. Contaminant concentrations at the future outfall site are
generally higher than similar measurements from a site in Cape Cod Bay. However, the highest 1995 mercury concentrations
were present in flounder from the future outfall site. The 1995 data indicated significantly increased concentrations of DDT
and PCBs over values from previous years. Liver lesions are present in flounder from all sites though the frequency of lesions
has been decreasing from year to year. In lobster, the highest organic contaminant concentrations in 1995 were present at the
future outfall site. Metal concentrations in lobster were lowest in Cape Cod Bay and similar at other sites, except for mercury 
5-3 December, 1997

which was highest at the future outfall site. Fish and shellfish contaminant concentrations have been consistently well below
levels that might cause any concern because of human consumption. 
The 1995 findings are consistent with results from earlier baseline years, which reported elevated levels of some toxic
contaminants in the lobster hepatopancreas (commonly referred to as the "tomalley"). This finding has been observed in
coastal Massachusetts waters for some time and was the basis for a Massachusetts Department of Public Health advisory on
the consumption of tomalley issued in 1988. 
5.2 Contingency Plan Trigger Parameters and Threshold Levels 
Based on results from the baseline studies, MWRA (1997) revised the Contingency Plan and linked potential management
decisions to the critical parameters. The trigger parameters and threshold levels applicable to Fish and Shellfish are
summarized in Table 5-2. The threshold values for edible tissue body burdens are more conservative than federal Food and
Drug Administration (FDA) limits based on human health risk. 
5.3 Phase II Monitoring Plan 
The Phase II Post-discharge Monitoring Plan will be consistent with monitoring conducted during Phase I Baseline Studies.
The basic premises remain the same -that of protection of human health for fish and shellfish consumption and maintenance
of the ecological health of the benthic communities. The details of the Phase n Monitoring Plan are considered below. See
Figure 5-1 for the location of the sampling stations. 
5-4 December, 1997

TABLE 5-2

Trigger Parameters for Fish and Shellfish

‘Parameter — ‘Levels. | Cention Level ‘Warning Level
Mercury in fish and - Human health FDA limit | 0.5 g/g wet weight 0.8 yg/g wet weight
shellfish tissue near
outfall
Total PCB in fish and + Human health FDA limit | 1 pg/g wet weight 1.6 g/g wet weight
shellfish tissue near
outfall
Lead in mussel near ~ Human health FDA limit | 2 ug/g wet weight 3 g/g wet weight
outfall
Lipid normalized toxics | - Indicator for ecological 2X baseline
in fish tissue near and human health
outfall
Liver disease incid + Indi for ecological Greater than average
in flounder health harbor prevalence from
1991 to 1997

5-5

December, 1997

Flounder and lobster 
Measurements: PCB, pesticides, mercury and lipids in flounder fillet, and lobster meat. PCB, PAH, trace metals, 
pesticides, and lipids for flounder liver, and lobster hepatopancreas. Histological analysis for flounder liver.
Animal size, mass, and dry/lipid weight will also be recorded. 
Location: For flounder, Deer Island flats, Future Outfall Site and East Cape Cod Bay, Nantasket Beach and Broad
Sound Sites sampled every year for histology with the Nantasket Beach and Broad Sound fish being
analyzed for chemical constituents every other year. For lobster, the Deer Island flats, Future Otufall Site
and East Cape Core Bay Sites are sampled every year. 
Frequency: Once a year during April for flounder and July-August for lobster. Biological material from fifteen
specimens from each station are pooled to form three composite samples of 5 individuals each for chemical
analysis. Fifty histological sections to be made per station for flounder liver. 
Mussels 
Measurements: PAH, PCB, pesticides, mercury and lead. 
Location: Outside the mixing zone near the Future Outfall Site, In-Harbor reference site (Discovery Site). 
Frequency: Caged mussels in replicate arrays (with > 50 mussels each) deployed at mid-depth or below the
pycnocline. Deployment will be for 60 days during June through August. Biological material from 50
mussels from a station as pooled to form five composite sample (10 specimens per sample) for chemical
analyses. 
Special Studies 
Currently there are no special studies to be conducted for Fish and Shellfish Monitoring under the Phase n Monitoring Plan.
Such studies will be considered on a case-by-case basis, such as in the event that threshold values are repeatedly exceeded. 
5.4 Data Evaluation and Comparison to Threshold Values 
Data evaluation and comparison to threshold values are conducted for two types of trigger parameters. The first is based on
comparison of contaminant levels to risk-based Caution and Warning Levels (Section 5.4. I) and the second is based on
relative increases in indicator parameter (Section 5.4.2). A summary of the data sources and comparison for evaluation of the
trigger parameters is contained in Table 5-3. 
5-6 December, 1997

TABLE 5-3
Data Sources and Comparison for
Trigger Parameter Threshold Values
me et one | Data: Tt | 7
A. Contaminants in Fish and Shellfish
1. Mercury in fish and shellfish meat Data: | Wet weight mercury concentration of
near future outfall site composite flounder fillet or lobster tail/claw
meat from future outfall site.
Reported In: | MWRA Annual Fish and Shellfish Report.
Comparison: | * Mean tissue concentration vs. Caution
Level and/or Waming Level
2. Total PCB in fish and shellfish meat Data: | Wet weight total PCB concentration of
near future outfall site composite flounder fillet or lobster tail/claw
meat from future outfall site.
Reported In: | MWRA Annual Fish and Shellfish Report.
Comparison: | * Mean tissue concentration vs. Caution
Level and/or Warning Level
3. Lead in mussel near future outfall site Data: | Wet weight lead concentration of caged
mussels from future outfall site.
Reported In: | MWRA Annual Fish and Shellfish Report.
Comparison: | * Mean tissue concentration vs. Caution
Level and/or Warning Level

bl

5-7

December, 1997

TABLE 5-3 (Cont’d)

Data Sources and Comparison for
Trigger Parameter Threshold Values

B. Ecological Health Parameter

4, Lipid-normalized toxics in fish and Data:
shellfish tissue near future outfall site

Lipid-normalized PAHs, PCBs/pesticides, and
mercury in founder liver and lobster
hepatopancreas from future outfall site

Reported In:

MWRA Annual Fish and Shellfish Report

‘Comparison:

* Mean tissue concentration vs. mean
“baseline” concentration

5. Liver disease incidence in flounder

Prevalence of centrotubular hydropic
vacuolation (CHV) in founder liver at future
outfall site.

Reported In:

MWRA Annual Fish and Shellfish Report.

Comparison:

* Mean prevalence of CHV vs. 1991-1997
baseline conditions in harbor.

5-8

December, 1997

5.4.1 Contaminant Concentrations in Fish and Shellfish 
The thresholds for fish and shellfish include the Caution Level and Warning Level for mercury and PCBs in fish and lobster
edible tissue and for lead in mussels. Exceedance of the Caution Level by the mean of composite samples collected near the
outfall should be noted but no further action would probably be required, unless an increasing trend appeared to be
developing. Exceedance of the Warning Level by the mean of the composite samples could lead to further analysis such as
revalidating lab results or running additional replicate analyses (if tissue is available). Further elaboration of contingency
plans for repeated exceedances of the Caution Level or Warning Level have yet to be established. However, based on current
trends (described in Section 2.1), there is no reason to anticipate that environmental conditions will change following
diversion to cause an exceedance of the Caution Level or Warning Level for the monitored species. 
5.4.2 Ecological Health Indicators 
In addition to the parameters which are used to evaluate potential human health risk, there are parameters which are used as
indicators of overall fish -and shellfish community health (Ecological Indicator Parameters). Unlike the contaminant
threshold parameters discussed in Section 5.4.1, these thresholds are triggered by relative rapid increase in parameter. These
thresholds include a relative increase (i.e., 2X the baseline level) of lipid-normalized toxics in the fish and shellfish edible
tissues or the incidence of liver lesion in flounder liver. The use of the relative increase criterion provides a pragmatic trigger
for investigating a rapid increase in the amount of tissue burdens or histopathological lesions. While the increase, in itself,
may not result in an adverse impact to the fish or shellfish communities, it does provide a measurable indication of potential
deterioration in water or sediment quality that may need further investigation. It should be recognized, however. that these
trigger parameters have indirect application to human health concerns as well. 
Application of a statistical comparison or evaluation of these Ecological Indicator Parameters in Phase II may require further
discussion as to what constitutes "baseline' conditions (i.e., does this only apply to years 1991-1997?). For example, it has not
been determined whether the mean, maximum, or range of values best constitutes the baseline. Summation and analysis of
the current baseline data (i.e., 1991-96 data sets) for the individual monitoring parameters has indicated that a significant
increase is detectable to a level below the Caution Level. A simple metric of statistical change (a one-tested T-test at 5%
significance) can be used to indicate significant change at levels below an exceedance of the Caution Level. This potentially
allows refinement of the monitoring program in the following year, if necessary, to modify or increase monitoring effort for
that parameter. In addition, some type of trend analysis (i.e., multivariate analysis) with comparison of the temporal and
spatial results will potentially be useful. 
Comparison of the histopathology results is straight forward due to the large sample size (50 per station). In this case, a
comparison of the mean prevalence of hepatocellular hydropic vacuolation to the mean and standard deviation of the
"baseline" years could be used to evaluate whether the year's results is significantly higher (e.g., one-tailed t-test or
nonparametric equivalent). 
5-9 December, 1997

6.0 REFERENCES 
Blake, J. and B. Hilbig. 1995. Combined work/quality assurance project plan for benthic monitoring: 1995-1997. 
MWRA Enviro. Quality Dept. Misc. Rpt. No. ms-34. Massachusetts Water Resources Authority, Boston, MA 68 pp. 
Bothner, M.H., Buchholtz ten Brink, M. Parmenter, C.M., D' Angelo, W.M. and M.W. Doughten. 1993. 
The distribution of silver and other metals in sediments from Massachusetts and Cape Cod Bays - an interim
compilation. U.S.G.S. Open Fill Report 93-725. 
Bowen, J.D., R.A. Zavistoski, S.J. Cibik, T. Loder, B. Howes, and C. Taylor. 1997 . Combined work/quality assurance
plan for baseline water quality monitoring: 1995-1997. MWRA Enviro. Quality Dept. Misc. Rpt. No. ms-45.
Massachusetts Water Resources Authority, Boston, MA. 93 pp. 
Butler, E., M. Hasegawa, and D. McGrath. 1995. Combined work/quality assurance plan for detailed effluent
characterization: 1995-1997. MWRA Enviro. Quality Dept. Misc. Rpt. No. ms-35. Massachusetts Water Resources
Authority, Boston, MA. 76 pp. 
Coats, D.A. 1995. 1994 Annual Soft Bottom Benthic Monitoring: Massachusetts Bay OutfaIl Studies MWRA
Environmental Quality Department Technical Report 95-20. Massachusetts Water Resources Authority, Boston, MA. 
EPA.1988. Boston Harbor Wastewater Conveyance System. Supplemental Environmental Impact Statement (SEIS). 
Environmental Protection Agency Region I, Boston, MA. 
Galya, D.P., J. Bleiler and K. Hickey. 1996. Outfall monitoring overview report: 1994. MWRA Department of
Environmental Quality Department Technical Report 96-4. Massachusetts Water Resources Authority Boston, MA. 
Hunt, C. and E.M. Baptiste. 1993. Evaluation of the Detectable Changes in Chemical Contaminants in Flounder and
Lobster Tissue. Appendix B of Annual review of toxic contaminants discharged by MWRA: 1993. 
Hunt, c. and M. Steinhauer. 1994a. MWRA Nutrient Indicator Workshop. MWRA Enviro. Quality Dept. Misc. Rpt. No.
ms-20. Massachusetts Water Resources Authority, Boston, MA. 1980 pp. 
Hunt, C. and M. Steinhauer. 1994b. Massachusetts Water Resources Authority Fish and Shellfish Science Review
Meeting. MWRA Enviro. Quality Dept. Misc. Rpt. No. ms-21. Massachusetts Water Resources Authority , Boston, MA.
114 pp. 
Hunt, C., M. Steinhauer, and K. Keay. 1994 . Massachusetts Water Resources Authority Benthic and Sediment Science
Meeting. MWRA Enviro. Quality Dept. Misc. Rpt. No. rns-22. Massachusetts Water Resources Authority, Boston, MA.
119 pp. 
Hunt, C.D., B.E. Buxton, A.D. Pate and D.E. Wells. 1995. Optimization of water column monitoring: statistical
treatments. MWRA Environmental Quality Department Technical Report 95-15. Massachusetts Water Resources Authority
Boston, MA. 
6-1 December, 1997

Hydroqual and Normandeau. 1995 . A water quality model for Massachusetts and Cape Cod Bays: calibration of the
Bays Eutrophication Model (BEM). MWRA Environmental Quality Department Technical Report 95-8. Massachusetts
Water Resources Authority Boston, MA. 403 pp. 
Hyland, J.L. and H. Costa. 1995. Examining linkages between contaminant inputs and their impacts on living marine
resources of the Massachusetts Bay ecosystem through application of the sediment quality triad method. MBP-95-03.
Massachusetts Bays Program, Boston, MA. 
Kelly, J. 1993. Nutrients and Massachusetts Bay: an update of eutrophication issues. MWRA Environmental Quality
Department Technical Report 93-17. Massachusetts Water Resources Authority Boston, MA. 
Long, E.R., D.D. MacDonald, S.L. Smith, and F.D. Calder. 1995. Incidence of adverse biological effects within the range
of chemical concentrations in marine and estuarine sediments. Environ. Management 19:81-97. 
MacDonald, D. 1993. Development of an approach to the assessment of sediment quality in Florida coastal waters. 
Report submitted to the Florida Coastal Management Program by MacDonald environmental Sciences Ltd., 122 pp. 
McCarthy, S., S. Cibik, and M. Mickelson. 1996a. Summary of MWRA water quality workshop: May 23,1996. MWRA
Enviro. Quality Dept. Misc. Rpt. No. ms-40. Massachusetts Water Resources Authority, Boston, MA. 234 pp. 
McCarthy, S., D.F. Mitchell, and K. Keay. I 996b. Summary of MWRA effluent, fish and shellfish workshop: May 24,
1996. MWRA Enviro. Quality Dept. Misc. Rpt. No. ms-4l. Massachusetts Water Resources Authority, Boston, MA. 128 pp. 
McCarthy, S ., J.A. Blake, and K. Keay. 1996c. Summary of MWRA benthic workshop: May 24,1996. MWRA Enviro.
Quality Dept. Misc. Rpt. No. ms-42. Massachusetts Water Resources Authority, Boston, MA. 212 pp. 
Mitchell, D.F., E. Butler, and D. McGrath. 1995. Combined work/quality assurance plan for fish and shellfish
monitoring: 1995-1997. MWRA Enviro. Quality Dept. Misc. Rpt. No. ms-39. Massachusetts Water Resources Authority,
Boston, MA. 71 pp. 
Mitchell, D.F., M. Wade, W. Sung and M. Moore. 1997. 1996 Toxics issue review report. MWRA Environmental Quality
Department Technical Report 97-2, Massachusetts Water Resources Authority, Boston, MA. 
MWRA. 1990. G.L.C. 30 Section 61. Revised Final Findings by the Massachusetts Water Resources Authority on the
Secondary Treatment Facilities Plan/EIR for Boston Harbor. Massachusetts Executive Office of Environmental Affairs File
Number 6136. Boston, MA. 
MWRA. 1991. Effluent outfall monitoring plan: phase I baseline studies. Massachusetts Water Resources Authority,
Boston, MA. 
MWRA. 1995. Draft MWRA effluent outfaIl monitoring plan: phase II post-discharge monitoring. Massachusetts
Water Resources Authority Boston, MA. 
MWRA. 1997. Contingency plan. Massachusetts Water Resources Authority Boston, MA, 41 pp. 
6-2 December, 1997

NOAA. 1988. Strategic Assessment of near coastal waters, Northeast case study. Susceptibility and status of Northeast
estuaries to nutrient discharges. National Oceanic and Atmospheric Administration, Rockville, MD. 
NOAA. 1997. NOAA's Estuarine Eutrophication Survey. Volume 3: North Atlantic region. Silver Spring, MD: Office of
Ocean Resources Conservation and Assessment. 45p. 
NRC. 1990. Managing Troubled Waters: The Role of Marine Monitoring. National Research Council. National Academy
Press, Washington, DC. 125pp. 
Parkhurst, D.F. 1985. Interpreting failure to reject null hypothesis. Bull. Ecol. Soc. 66:301-302. 
Pederson, J. 1992. Letters to Susan F. Tierney and Julie Belaga recommending approval of monitoring plan, dated March 9,
1992. Also letter from Susan Tiemey to Douglas MacDonald urging support of monitoring plan, dated March 19, 1992. 
6-3 December, 1997

Attachment O 
Contingency Plan 
(Note: Please contact bmcarthy@mwra.state.ma.us to obtain copies.)

Attachment P 
Pollution Prevention 
1. Pollution prevention fact sheet examples: 
(1) DO NOT deposit used motor oil on the ground or down a drain. INSTEAD, bring your used oil
back to where it was purchased. (A seller must accept used oil of up to 2 gallons a day, free of
charge, from a customer with a receipt of purchase under the MA Used Oil Return Law, MA
General Law Chapter 21, Section 52A.); 
(2) RECYCLE used anti-freeze: some car service stations have a recycling service for this; 
(3) CALL hotline phone numbers for pollution prevention information and ideas: 
(1.) USEPA Pollution Prevention Information Clearinghouse - 800/424-9346 - for information
and answers to questions about reducing or eliminating discharges and/or emissions to
the environment through source reduction and environmentally sound recycling; 
(2.) USEPA National Pesticides Telecommunications Network Hotline - 800/858-7378 - for
information on pesticide-related health, toxicity, and minor cleanup to physicians,
veterinarians, fire departments, government agencies, and the general public; 
(3.) USEPA Unleaded Fuel Hotline - 800/631-2700 in MA; 
(4.) MADEP Used Oil Hotline - 617/556-1022 - for information on available collection
locations; 
(5.) MA Office of Technical Assistance - 617/727-3260, extension 696 - for information on
alternate household cleaners; 
(4) USE environmentally safe household cleaners. (Follow the recipes from this fact sheet, or call the
MA Office of Technical Assistance at 617/727-3260 extension 696 for more information on sources.
For your own safety, do not create your own recipes); 
(1.) For a good surface cleaner - add vinegar + salt; 
(2.) general cleaner - 1 quart warm water + 4 tablespoons baking powder; 
(3.) deodorizer/surface cleaner - damp sponge + baking soda; 
(4.) carpet cleaner - sweep the carpet to make the nap stand up, cover with a layer of baking
soda, wait 15 minutes or more, vacuum;
(5.) oven cleaner - sprinkle salt on a spill while the oven is still warm, rinse with off with a
cloth + warm water;
(6.) drain cleaner - mechanical means, such as a plunger or plumbers snake found at hardware
stores;
(7.) toilet bowl cleaner - sprinkle baking soda, then drizzle with vinegar and scour with a toilet 
brush;
(8.) glass cleaner - use equal parts of water + white vinegar and dry with a soft cloth;
(9.) gold - clean with toothpaste;
(10.) silver - clean with toothpaste, or let stand in sour milk over night and rinse with a cold 
water 
and polish dry with a soft cloth; 
(11.) stainless steel - clean with baking soda and a scouring pad. Rub stainless steel sinks
with
olive oil or club soda to remove streaks; and,

(12.) grease stains on fabric - apply a paste of cornstarch + water, let dry and rub off. Or,
scrub spot with toothpaste. 
2. Examples of how to involve established organizations with the implementation of pollution prevention
public awareness programs, within the MWRA treatment system: 
(1.) Work with the boy scouts to establish a badge that would require boy scouts to
personally handout fact sheets, with adult supervision, to neighbors and explain and
encourage pollution prevention ideas to the visited person. The badge could be called
the "environmental community outreach and education badge"; 
(2.) Work with the girl scouts to establish a badge using the idea described above; 
(3.) Work with school boards to establish an environmental education curriculum; and, 
(4.) Establish an "MWRA Stenciling Day" and request volunteer assistance to stencil street
drains with an environmental awareness message. Advertise this volunteer activity in the
newspaper, television, or radio.

Attachment Q 
Marine Acute Toxicity Test Procedure and Protocol 
I. GENERAL REQUIREMENTS 
The permittee shall conduct acceptable acute toxicity tests in accordance with the appropriate test protocols
described below: 
! ! Mysid Shrimp ( Mysidopsis bahia ) definitive 24 hour test. 
! ! Inland Silverside ( Menidia beryllina ) definitive 24 hour test. 
Acute toxicity data shall be reported as outlined in Section VIII. 
II. METHODS 
Methods to follow are those recommended by EPA in: 
Weber, C.I. et al. Methods for Measuring the Acute Toxicity of Effluents to Freshwater and Marine Organisms , 
Fourth Edition. Environmental Monitoring Systems Laboratory, U.S. Environmental Protection Agency, Cincinnati, 
OH. August 1993, EPA/600/4-90/027F. 
Any exceptions are stated herein. 
III. SAMPLE COLLECTION 
A discharge sample shall be collected. Aliquots shall be split from the sample, containerized and preserved (as per
40 CFR Part 136) for the chemical and physical analyses. The remaining sample shall be dechlorinated (if detected) in
the laboratory using sodium thiosulfate for subsequent toxicity testing. ( Note that EPA approved test methods
require that samples collected for metals analyses be preserved immediately after collection. ) Grab samples must be
used for pH, temperature, and total residual oxidants (as per 40 CFR Part 122.21). 
Standard Methods for the Examination of Water and Wastewater describes dechlorination of samples (APHA, 1992).
Dechlorination can be achieved using a ratio of 6.7 mg/L anhydrous sodium thiosulfate to reduce 1.0 mg/L chlorine.
A thiosulfate control (maximum amount of thiosulfate in lab control or receiving water) should also be run. 
All samples held overnight shall be refrigerated at 4 o C. 
IV. DILUTION WATER 
A grab sample of dilution water used for acute toxicity testing shall be collected at a point away from the discharge
which is free from toxicity or other sources of contamination. Avoid collecting near areas of obvious road or
agricultural runoff, storm sewers or other point source discharges. An additional control (0% effluent) of a standard
laboratory water of known quality shall also be tested. 
If the receiving water diluent is found to be, or suspected to be toxic or unreliable, an alternate standard dilution
water of known quality with a conductivity, salinity, total suspended solids, and pH similar to that of the receiving
water may be substituted AFTER RECEIVING WRITTEN APPROVAL FROM THE PERMIT ISSUING
AGENCY(S) . Written requests for use of an alternative dilution water should be mailed with supporting
documentation to the following address: 
Director 
Office of Ecosystem Protection 
U.S. Environmental Protection Agency-New England

_________________________________________________________________ 
JFK Federal Building (CAA) 
Boston, MA 02203
It may prove beneficial to have the proposed dilution water source screened for suitability prior to toxicity testing.
EPA strongly urges that screening be done prior to set up of a full definitive toxicity test any time there is question
about the dilution water's ability to support acceptable performance as outlined in the 'test acceptability' section of
the protocol. 
V. TEST CONDITIONS AND TEST ACCEPTABILITY CRITERIA 
EPA New England requires tests be performed using four replicates of each control and effluent concentration
because the non-parametric statistical tests cannot be used with data from fewer replicates. The following tables
summarize the accepted Mysid and Menidia toxicity test conditions and test acceptability criteria: 
EPA NEW ENGLAND RECOMMENDED EFFLUENT TOXICITY TEST CONDITIONS FOR THE MYSID, 
MYSIDOPSIS BAHIA 24 HOUR TEST 1 
1. Test type Static, non-renewal 
2. Salinity 25ppt + 10 percent for all dilutions by adding dry ocean salts 
3. Temperature ( o C) 20 o C + 1 o C or 25 o C + 1 o C 
4. Light quality Ambient laboratory illumination 
5. Photoperiod 16 hour light, 8 hour dark 
6. Test chamber size 250 ml 
7. Test solution volume 200 ml 
8. Age of test organisms 1-5 days 
9. No. Mysids per test chamber 10 
10. No. of replicate test chambers per
treatment 
4 
11. Total no. Mysids per test concentration 40 
12. Feeding regime Light feeding using concentrated Artemia nauplii while holding
prior to initiating the test 
13. Aeration2 None 
14. Dilution water Natural seawater, or deionized water mixed with artificial sea salts 
15. Dilution factor > 0.5 
16. Number of dilutions 3 5 plus a control. An additional dilution at the permitted effluent
concentration (% effluent) is required if it is not included in the
dilution series. 
17. Effect measured Mortality - no movement of body appendages on gentle prodding 
18. Test acceptability 90% or greater survival of test organisms in control solution

_________________________________________________________________ 
_________________________________________________________________ 
19. Sampling requirements For on-site tests, samples are used within 24 hours of the time that
they are removed from the sampling device. For off-site tests,
samples must be first used within 36 hours of collection. 
20. Sample volume required Minimum 1 liter for effluents and 2 liters for receiving waters 
Footnotes: 
1. Adapted from EPA/600/4-90/027F. 
2. If dissolved oxygen falls below 4.0 mg/L, aerate at rate of less than 100 bubbles/min. Routine D.O. checks are
recommended. 
3. When receiving water is used for dilution, an additional control made up of standard laboratory dilution water
(0% effluent) is required. 
EPA NEW ENGLAND RECOMMENDED TOXICITY TEST CONDITIONS FOR THE INLAND SILVERSIDE, 
MENIDIA BERYLLINA 24 HOUR TEST 1 
1. Test Type Static, non-renewal 
2. Salinity 25 ppt + 2 ppt by adding dry ocean salts 
3. Temperature 20 o C + 1 o C or 25 o C + 1 o C 
4. Light Quality Ambient laboratory illumination 
5. Photoperiod 16 hr light, 8 hr dark 
6. Size of test vessel 250 mL (minimum) 
7. Volume of test solution 200 mL/replicate (minimum) 
8. Age of fish 9-14 days; 24 hr age range 
9. No. fish per chamber 10 (not to exceed loading limits) 
10. No. of replicate test vessels per treatment 4 
11. total no. organisms per concentration 40 
12. Feeding regime Light feeding using concentrated Artemia nauplii while holding
prior to initiating the test 
13. Aeration 2 None 
14. Dilution water Natural seawater, or deionized water mixed with artificial sea 
salts. 
15. Dilution factor > 0.5 
16. Number of dilutions 3 5 plus a control. An additional dilution at the permitted
concentration (% effluent) is required if it is not included in the
dilution series. 
3

_________________________________________________________________ 
17. Effect measured Mortality-no movement on gentle prodding. 
18. Test acceptability 90% or greater survival of test organisms in control solution 
19. Sampling requirements For on-site tests, samples must be used within 24 hours of the
time they are removed from the sampling device. Off-site test
samples must be used within 36 hours of collection. 
20. Sample volume required Minimum 1 liter for effluents and 2 liters for receiving waters. 
Footnotes : 
1. Adapted from EPA/600/4-90/027F. 
2. If dissolved oxygen falls below 4.0 mg/L, aerate at rate of less than 100 bubbles/min. Routine D.O. checks
recommended. 
3. When receiving water is used for dilution, an additional control made up of standard laboratory dilution water
(0% effluent) is required. 
VI. CHEMICAL ANALYSIS 
At the beginning of the static acute test, pH, specific conductance, salinity, total residual oxidants, and temperature
must be measured at the beginning and end of each 24 hour period in each dilution and in the controls. The
following chemical analyses shall be performed for each sampling event. 
Parameter Minimum 
Quantification 
Effluent Diluent Level (mg/L) 
pH x x -- 
Specific Conductance x x -- 
Salinity x x PT(o/oo) 
Total Residual Oxidants *1 x x 0.05 
Total Solids and Suspended Solids x x -- 
Ammonia x x 0.1 
Total Organic Carbon x x 0.5 
Total Metals 
Cd x 0.001 
Cr x 0.005 
Pb x x 0.005 
Cu x x 0.0025 
4

Zn x x 0.0025 
Ni x x 0.004 
A1 x x 0.02 
Superscript : 
*1 Total Residual Oxidants 
Either of the following methods from the 18th Edition of the APHA Standard Methods for the Examination 
of Water and Wastewater must be used for these analyses: 
-Method 4500-Cl E Low Level Amperometric Titration (the preferred method); 
-Method 4500-CL G DPD Photometric Method. 
or use USEPA Manual of Methods Analysis of Water or Wastes , Method 330.5. 
VII. TOXICITY TEST DATA ANALYSIS 
LC50 Median Lethal Concentration 
An estimate of the concentration of effluent or toxicant that is lethal to 50% of the test organisms during the time
prescribed by the test method. 
Methods of Estimation: 
! Probit Method 
! Spearman-Karber 
! Trimmed Spearman-Karber 
! Graphical 
See flow chart in Figure 6 on page 77 of EPA 600/4-90/027F for appropriate method to use on a given data set. 
No Observed Acute Effect Level (NOAEL) 
See flow chart in Figure 13 on page 94 of EPA 600/4-90/027F. 
VIII. TOXICITY TEST REPORTING 
The following must be reported: 
! Description of sample collection procedures, site description; 
! Names of individuals collecting and transporting samples, times and dates of sample collection and analysis 
on chain-of-custody; and 
! General description of tests: age of test organisms, origin, dates and results of standard toxicant tests; light
and temperature regime; other information on test conditions if different than procedures recommended. 
Reference toxicity test data must be included. 
! Raw data and bench sheets. 
! All chemical/physical data generated. (Include minimum detection levels and minimum quantification 
5

levels.) 
! Provide a description of dechlorination procedures (as applicable). 
! Any other observations or test conditions affecting test outcome. 
! Statistical tests used to calculate endpoints. 
6

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Attachment R 
Fresh Water Acute Toxicity Test Procedure and Protocol 
o Daphnids ( Ceriodaphnia dubia ) definitive 24 hour acute test. 
o Fathead Minnow ( Pimephales promelas ) definitive 24 hour acute test. 
I. GENERAL REQUIREMENTS 
The permittee shall conduct acceptable toxicity tests in accordance with the appropriate test protocols described
below. The permittee must collect discharge samples and perform the toxicity tests that are required by Part I of the
NPDES permit. Acute toxicity test data shall be reported as outlined in Section IX. 
II. TEST FREQUENCY AND SAMPLING REQUIREMENTS 
See Part I of the NPDES permit for sampling location, sample type, test frequency, test species, and test date(s) 
requirements. Chain of Custody information should be provided for each sample tested. 
An acute toxicity test sampling event is defined as a single discharge (composite or grab) sample. 
III. METHODS
Methods should follow those recommended by EPA in:
Peltier, W., and Weber, C.I., 1985. Methods for Measuring the Acute Toxicity of Effluents to Freshwater , Third 
Edition. Office of Research and Development, Cincinnati, OH. EPA/600/4-90-027 Rev. 9/91 Section 6.1.).
Any exceptions are stated herein. 
IV. SAMPLE COLLECTION 
A discharge sample shall be collected. Aliquots shall be split from the sample, containerized and preserved (as per
40 CFR Part 136) for chemical and physical analyses required. The remaining sample shall be dechlorinated (if
necessary) in the laboratory using sodium thiosulfate for subsequent toxicity testing. Grab samples must be used
for pH, temperature, and total residual chlorine (as per 40 CFR Part 122.21). 
The Methods for Aquatic Toxicity Identification Evaluations (Phase I) EPA/600/3-88/034, Section 8.7, provides
detailed information regarding the use of sodium thiosulfate ( i.e. dechlorination). 
All samples held overnight shall be refrigerated at 4 o C. 
V. REGION I RECOMMENDED EFFLUENT TOXICITY TEST CONDITIONS FOR THE DAPHNIDS
( Ceriodaphnia dubia and ) 24 HOUR ACUTE TESTS 1 
1. Test type Static, non-renewal 
2. Temperature ( o C) 25 + 1 o C 
3. Light quality Ambient laboratory illumination 
4. Photoperiod 16 hour light, 8 hour dark 
5. Test chamber size Minimum 30 ml

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_________________________________________________________________ 
6. Test solution volume Minimum 25 ml 
7. Age of test organisms 1-24 hours (neonates) 
8. No. daphnids per test chamber 5 
9. No. of replicate test chambers per treatment 4 
10. Total no. daphnids per test concentration 20 
11. Feeding regime None 
12. Aeration None 
13. Number of dilutions 1 plus a control. 
14. Effect measured Mortality - no movement of body or appendages on gentle 
prodding 
15. Test acceptability 90% or greater survival of test organisms in control solution 
16. Sampling requirements For on-site tests, samples must be used within 24 hours of the
time that they are removed from the sampling device. For off-
site tests, samples must first be used within 24 hours of
collection. 
17. Sample volume required Minimum 2 liters 
Footnotes: 
1. Adapted from EPA/600/4-85/013. 
2. Standard prepared dilution water must have hardness requirements to generally reflect the characteristics of
the receiving water. 
VI. REGION I RECOMMENDED TEST CONDITIONS FOR THE FATHEAD MINNOW ( Pimephales promelas ) 24
HOUR ACUTE TEST 1 
1. Test Type: Static, non-renewal 
2. Temperature ( o C): 25 + 1 o C 
3. Light quality: Ambient laboratory illumination 
4. Photoperiod: 16 hr light, 8 hr dark 
5. Size of test vessels: 250-1000 ml 
6. Volume of test solution: Minimum 200ml/replicate 
7. Age of fish: 1-14 days 
2

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8. No. of fish per chamber: 10 (not to exceed loading limits) 
9. No. of replicate test vessels per 2 
treatment: 
10. Total no. organisms per concentration: 20 
11. Feeding regime: None 
12. Aeration: None, unless DO concentration falls below 40% of saturation,
at which time gentle single-bubble aeration should be started
at a rate of less than 100 bubbles/min. (Routine DO check
recommended.) 
13. Number of dilutions: 1 plus a control. 
14. Effect measured: Mortality-no movement on gentle prodding 
15. Test acceptability: 90% or greater survival of test organisms in control solution 
16. Sampling requirements: For on-site tests, samples must be used within 24 hours of the
time that they are removed from the sampling device. For off-
site tests, samples must be first used within 48 hours of
collection. 
17. Sample volume required: Minimum 4 liters 
Footnotes: 
1. Adapted from EPA/600/4-85/013. 
2. Standard dilution water must have hardness requirements to generally reflect characteristics of the receiving
water. 
VII. CHEMICAL ANALYSIS 
The following chemical analyses shall be performed for each sampling event. 
Minimum
Parameter Detection 
Effluent Diluent Limit (mg/L) 
Hardness *1 x x 0.5
Alkalinity x x 2.0
pH x x --
Specific Conductance x x ---
Total Solids and Suspended Solids x x --
Ammonia x x 0.1
Total Organic Carbon x x 0.5
Total Residual Chlorine (TRC) *2 x x 0.02 
Total Metals 
3

Cd x 0.005 
Cr, Ni x 0.05 
Pb, Cu x x 0.005 
Zn, Al x x 0.02 
Mg, Ca x x 0.05 
Superscripts: 
*1 Method 314A (hardness by calculation) from APHA (1985) Standard Methods for the Examination of
Water and Wastewater . 16th Edition. 
*2 Total Residual Chlorine 
Methods: either of the following methods the 16th edition of the APHA (1985) Standard Methods for the
Examination of Water and Wastewater must be used for these analyses. 
Method 408-C (Amperometric Titration 

The text goes on. The rest is in the file.