Part I
U.S. Environmental Protection Agency · from the EPA · 68 pages · 590 KB
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NPDES Permit No. MA0103284 2023 Draft Permit
AUTHORIZATION TO DISCHARGE UNDER THE
NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM
In compliance with the provisions of the Federal Clean Water Act as amended, 33 U.S.C. §§ 1251 et
seq. (the “CWA”),
Massachusetts Water Resource Authority (MWRA)
is authorized to discharge from the facility located at
MWRA Deer Island Treatment Plant (DITP)
190 Tafts Avenue
Winthrop, MA 02152
to the receiving water named
Receiving Water Segment Outfall
Massachusetts Bay Undefined, 314 CMR 4.06. Table 23 T01
and
Four (4) Combined Sewer Overflow (CSO) Treatment Facilities with 5 outfalls
to the receiving waters named
Receiving Water Segment CSO Treatment Facility Name Outfalls
Boston Inner Harbor MA70-02 Prison Point MWR203
Boston Inner Harbor MA70-02 Union Park MWR215
Mystic River MA71-03 Somerville Marginal MWR205
Upper Mystic River MA71-02 Somerville Marginal MWR205A
Charles River MA72-38 Cottage Farm MWR201
and
Six (6) additional Combined Sewer Overflow (CSO) Outfalls (See Attachment A)
in accordance with effluent limitations, monitoring requirements and other conditions set forth herein.
NOTE: The former near shore DITP outfalls: 001, 002, 003, 004 and 005, are not authorized under the
Permit. The Permit no longer requires the Permittee to maintain these nearshore Deer Island outfalls
as a contingency option.
The Massachusetts municipalities listed below are identified as CSO-responsible Co-permittees
responsible for Part B., Combined Sewer Overflows, Part C., Unauthorized Discharges, Part D.,
Notice of Elimination, Part E., Operation and Maintenance, which includes conditions regarding the
operation and maintenance of the collection systems owned and operated by the municipalities; Part
F., Alternate Power Source, and Part J., Reporting Requirements. The list of CSO outfalls, the CSO-
responsible party, receiving waters and locations are found in Attachment A .
NPDES Permit No. MA0103284 2023 Draft Permit
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MAC053284 MAC093284 MAC113284 MAC293284
City of Boston
Boston Water and
Sewer Commission
980 Harrison Avenue
Boston, MA 02119
City of Cambridge
Department of Public
Works
147 Hampshire Street
Cambridge, MA
02139
City of Chelsea
Department of Public
Works
380 Beacham Street
Chelsea, MA 02150
City of Somerville
Department of Public
Works
1 Franey Road
Somerville, MA
02144
The Massachusetts municipalities in Attachment B are identified as Co-permittees related to
operation and maintenance of the sewer systems in compliance with the Standard Conditions of Part II
and the terms and conditions of Part C., Unauthorized Discharges, Part E., Operation and
Maintenance, which includes conditions regarding the operation and maintenance of the collection
systems owned and operated by the municipality, Part F., Alternate Power Source, and Part J.
Reporting Requirements.
The Permittee, CSO-responsible Co-permittees and each Co-permittee are severally liable for their
own activities under the Standard Conditions of Part II, Parts C, E, F, and required reporting under
Part J with respect to the portions of the sewer system that they own or operate. They are not liable for
violations of the Standard Conditions of Part II, Parts C, E, F and Part J committed by others relative
to the portions of the collection system owned and operated by others. Nor are they responsible for
any reporting that is required of other Permittees under the Standard Conditions of Part II, Part C, Part
E, Part F, and Part J. The responsible municipal departments are found in Attachment B .
This Permit shall become effective on the first day of the calendar month immediately following 60
days after signature. 1
This Permit expires at midnight, five years from the last day of the month preceding the effective date.
This Permit supersedes the NPDES Permit No. MA0103284 issued on May 20, 1999, and
subsequently modified on July 10, 2000; NPDES Permit No. MA0101192 issued on March 28, 2003
and subsequently modified on April 10, 2007; NPDES Permit No. MA0101974 issued on September
30, 2009; NPDES Permit No. MA0101877 issued on November 26, 2013; and NPDES Permit No.
MA0101982 issued on June 11, 2012.
This Permit consists of Part I including the cover page(s), Attachment A (Authorized CSO Outfalls
and Responsible Parties), Attachment B (MWRA Member Communities named as Co-permittees),
Attachment C (Marine Acute Toxicity Test Procedure and Protocol, July 2012), Attachment D
(Marine Chronic Toxicity Test Procedure and Protocol, November 2013), Attachment E (Freshwater
Acute Toxicity Test Procedure and Protocol, February 2011), Attachment F (Reassessment of
Technically Based Industrial Discharge Limits), Attachment G (Industrial Pretreatment Annual
Report), Attachment H (PFAS Analyte List), Attachment I (Authorized Typical Year CSO
1 Pursuant to 40 Code of Federal Regulations (CFR) § 124.15(b)(3), if no comments requesting a change to the Draft
Permit are received, the permit will become effective upon the date of signature. Procedures for appealing EPA’s Final
Permit decision may be found at 40 CFR § 124.19.
NPDES Permit No. MA0103284 2023 Draft Permit
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Discharge Activations and Volumes), Attachment J (Charles River Basin CSO Variance
Determination), Attachment K (Alewife and Upper Mystic River Basin CSO Variance
Determination) and Part II (NPDES Part II Standard Conditions, April 2018).
Signed this day of
_________________________
Ken Moraff, Director
Water Division
Environmental Protection Agency
Region 1
Boston, MA
NPDES Permit No. MA0103284 2023 Draft Permit
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PART I
A. EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS FOR OUTFALL T01
1. During the period beginning on the effective date and lasting through the expiration date, the Permittee, MWRA, is authorized to
discharge treated effluent through Outfall Serial Number T01 to Massachusetts Bay. The discharge shall be limited and monitored
as specified below; the receiving water and the influent shall be monitored as specified below.
Effluent Characteristic
Effluent Limitation Monitoring Requirements 1,2,3
Average Monthly Average
Weekly Maximum Daily Measurement
Frequency
Sample
Type 4
Rolling Average Effluent Flow 5,6 361 MGD 5 --- --- Continuous Recorder
Effluent Flow 5,6 Report MGD --- Report MGD Continuous Recorder
CBOD5 25 mg/L 40 mg/L Report mg/L 1/Day Composite
CBOD5 Removal 7 ≥ 85 % --- --- 1/Month Calculation
TSS 30 mg/L 45 mg/L Report mg/L 1/Day Composite
TSS Removal 7 ≥ 85 % --- --- 1/Month Calculation
pH Range 8 6.0 - 8.5 S.U. 1/Day Grab
Total Residual Chlorine 9,10 45 6 μg/L --- 631 μg/L 3/Day Grab
Fecal Coliform 9,10,11,12 980 organisms
/100 mL --- 1,960
organisms/100 mL 3/Day Grab
Enterococci 9,10,12
(April 1 through October 31) 2,450 cfu/100 mL --- 9,100 cfu/100 mL 3/Day Grab
Oil and Grease 13 Non-detect mg/L --- --- 1/Day Grab
Ammonia Nitrogen 14 Report mg/L --- Report mg/L 1/Month Composite
Total Kjeldahl Nitrogen 14
(April 1 through October 31)
(November 1 through March 31)
Report mg/L --- Report mg/L 1/Week
1/Month
Composite
Nitrate + Nitrite 14
(April 1 through October 31)
(November 1 through March 31)
Report mg/L --- Report mg/L 1/Week
1/Month
Composite
Total Nitrogen 14
(April 1 through October 31) Report mg/L --- Report mg/L 1/Week Calculation
NPDES Permit No. MA0103284 2023 Draft Permit
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Effluent Characteristic
Effluent Limitation Monitoring Requirements 1,2,3
Average Monthly Average
Weekly Maximum Daily Measurement
Frequency
Sample
Type 4
(November 1 through March 31) 1/Month
PFAS Analytes 15 --- --- Report ng/L 1/Quarter Grab
Adsorbable Organic Fluorine 16 --- --- Report ng/L 1/Quarter Grab
Effluent Characteristic
Effluent Limitation Monitoring Requirements 1,2,3
Average Monthly Average
Weekly Maximum Daily Measurement
Frequency
Sample
Type 4
Whole Effluent Toxicity (WET) Testing 17,18
LC50 --- --- ≥ 100 % 1/Quarter Composite
C-NOEC --- --- ≥ 1.5 % 1/Quarter Composite
Salinity --- --- Report ppt 1/Quarter Composite
Ammonia Nitrogen --- --- Report mg/L 1/Quarter Composite
Total Cadmium --- --- Report mg/L 1/Quarter Composite
Total Copper --- --- Report mg/L 1/Quarter Composite
Total Nickel --- --- Report mg/L 1/Quarter Composite
Total Lead --- --- Report mg/L 1/Quarter Composite
Total Zinc --- --- Report mg/L 1/Quarter Composite
Total Organic Carbon --- --- Report mg/L 1/Quarter Composite
NPDES Permit No. MA0103284 2023 Draft Permit
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Ambient Characteristic 19
Reporting Requirements Monitoring Requirements 1,2,3
Average
Monthly
Average
Weekly Maximum Daily Measurement
Frequency Sample Type 4
Fecal Coliform 11,12 – Surface --- --- Report
organisms/100 mL 1/Month Grab
Fecal Coliform 11,12 – Below pycnocline --- --- Report
organisms/100 mL 1/Month Grab
Enterococci 11,12 - Surface
(April 1 through October 31) --- --- Report cfu/100
mL 1/Month Grab
Enterococci 11,12 - Below pycnocline
(April 1 through October 31) --- --- Report cfu/100
mL 1/Month Grab
Salinity --- --- Report ppt 1/Quarter Grab
Ammonia Nitrogen --- --- Report mg/L 1/Quarter Grab
Total Cadmium --- --- Report mg/L 1/Quarter Grab
Total Copper --- --- Report mg/L 1/Quarter Grab
Total Nickel --- --- Report mg/L 1/Quarter Grab
Total Lead --- --- Report mg/L 1/Quarter Grab
Total Zinc --- --- Report mg/L 1/Quarter Grab
Total Organic Carbon --- --- Report mg/L 1/Quarter Grab
Dissolved Organic Carbon 20 --- --- Report mg/L 1/Quarter Grab
pH 21 --- --- Report S.U. 1/Quarter Grab
Temperature 21 --- --- Report °C 1/Quarter Grab
NPDES Permit No. MA0103284 2023 Draft Permit
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Influent Characteristic
Reporting Requirements Monitoring Requirements 1,2,3
Average
Monthly
Average
Weekly
Maximum
Daily
Measurement
Frequency Sample Type 4
7
CBOD5 Report mg/L --- --- 2/Month Composite
TSS 7 Report mg/L --- --- 2/Month Composite
PFAS Analytes 15 --- --- Report ng/L 1/Quarter Grab
Adsorbable Organic Fluorine 16 --- --- Report ng/L 1/Quarter Grab
Sludge Characteristic
Reporting Requirements Monitoring Requirements 1,2,3
Average
Monthly
Average
Weekly
Maximum
Daily
Measurement
Frequency Sample Type 4
PFAS Analytes 15 --- --- Report ng/g 1/Quarter Grab 21
NPDES Permit No. MA0103284 2023 Draft Permit
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Footnotes:
1. All samples shall be collected in a manner to yield representative data. A routine
sampling program shall be developed in which samples are taken at the same location,
same time and same days of the week each month. Occasional deviations from the
routine sampling program are allowed, but the reason for the deviation shall be
documented as an electronic attachment to the applicable discharge monitoring report.
The Permittee shall report the results to the Environmental Protection Agency Region 1
(EPA) and the MassDEP of any additional testing above that required herein, if testing is
in accordance with 40 CFR Part 136.
2. In accordance with 40 CFR § 122.44(i)(1)(iv), the Permittee shall monitor according to
sufficiently sensitive test procedures (i.e., methods) approved under 40 CFR Part 136 or
required under 40 CFR chapter I, subchapter N or O, for the analysis of pollutants or
pollutant parameters (except WET). A method is “sufficiently sensitive” when: 1) The
method minimum level (ML) is at or below the level of the effluent limitation established
in the permit for the measured pollutant or pollutant parameter; or 2) The method has the
lowest ML of the analytical methods approved under 40 CFR Part 136 or required under
40 CFR chapter I, subchapter N or O for the measured pollutant or pollutant parameter.
The term “minimum level” refers either to the sample concentration equivalent to the
lowest calibration point in a method or a multiple of the method detection limit (MDL),
whichever is higher. Minimum levels may be obtained in the following ways: they may
be published in a method; they may be based on the lowest acceptable calibration point
used by a laboratory; or they may be calculated by multiplying the MDL in a method, or
the MDL determined by a laboratory, by a factor.
3. When a parameter is not detected above the ML, the Permittee must report the data
qualifier signifying less than the ML for that parameter (e.g., < 50 μg/L, if the ML for a
parameter is 50 μg/L). For reporting an average based on a mix of val ues detected and not
detected, assign a value of “0” to all non-detects for that reporting period and report the
average of all the results.
4. A “grab” sample is an individual sample collected in a period of less than 15 minutes. A
“composite” sample is a composite of at least twenty-four (24) grab samples taken during
one consecutive 24-hour period, either collected at equal intervals and combined
proportional to flow or continuously collected proportional to flow.
5. The 365-calendar day running average dry day flow shall not exceed 361 MGD. For this
purpose, a “dry day” is defined as a day with 0.09 inches of precipitation or less and no
snow melt, provided that the precipitation on the previous day is less than 0.3 inch, and
the precipitation on the day two days prior to the day in question is less than 1.0 inch, and
the precipitation on the day three days prior to the day in question is less than 2.0 inches.
A day with snow melt is defined as a day when there is snow on the ground and the air
NPDES Permit No. MA0103284 2023 Draft Permit
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temperature rises above 32 degrees Fahrenheit. Flow from the CSO storage facilities is
not included in the dry day calculation.
Compliance with this flow limit will be determined each month by calculating the
average dry day flow over the previous 365 calendar days. The once-a-month calculation
shall include all dry day flow that occurred during the reporting month [Total dry day
flow/total number of dry days].
6. Within 24 hours after the commencement of any diversions of wastewater around
secondary treatment facilities at the DITP, the Permittee shall notify EPA by telephone or
email of the commencement of the diversion of wastewater around secondary treatment
facilities.
Within 5 days of the commencement of any diversion of wastewater around secondary
treatment facilities at DITP, the Permittee shall provide EPA and MassDEP a written
submission containing a description of the diversion, its cause and the period of the
diversion, including its exact dates and times. If the diversion has not stopped by when
the written submission is due, the written submission shall also include a statement as to
the anticipated time it is expected to continue, and any steps taken or planned to reduce or
eliminate the diversion.
A bypass of secondary treatment is subject to the requirements of Part II.B.4.and Part
II.D.1.e. of this Permit.
Flows shall be measured using a meter. The requirement to measure flows which bypass
secondary treatment using a meter shall take effect 6 months following the effective date
of the Permit.
The Permittee shall not add septage to the waste stream at the treatment plant during
activation of the secondary treatment bypass.
7. For the purposes of calculating CBOD5 and TSS percent removal, the Permittee shall
only use the data from dry days. The influent samples shall be taken on dry days.
A “dry day” is defined as a day with 0.09 inches of precipitation or less and no snow
melt, provided that the precipitation on the previous day is less than 0.3 inch, and the
precipitation on the day two days prior to the day in question is less than 1.0 inch, and the
precipitation on the day three days prior to the day in question is less than 2.0 inches. A
day with snow melt is defined as a day when there is snow on the ground and the air
temperature rises above 32 degrees Fahrenheit. Flow from the CSO storage facilities is
not included in the dry day calculation.
NPDES Permit No. MA0103284 2023 Draft Permit
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8. The pH shall be within the specified range at all times. The minimum and maximum pH
sample measurement values for the month shall be reported in standard units (S.U.). See
Section I.K.2. of this Permit for additional State requirements.
9. The Permittee shall minimize the use of chlorine while maintaining adequate bacterial
control. Monitoring for total residual chlorine (TRC) is only required for discharges
which have been previously chlorinated, or which contain residual chlorine.
The Permittee may simulate the chlorine contact time in the outfall pipe prior to
dechlorination by holding the sample in conditions similar to those that would be present
at the outfall pipe, T01, before measuring the TRC, Enterococcus and fecal coliform.
The holding time shall be calculated based on the effluent flow at the time of sample
collection and time for disinfection. The holding time and supporting calculation shall be
submitted as an attachment to the monthly DMRs. The Permittee may either use process
software or manual means for calculation.
Chlorination and dechlorination systems shall include an alarm system for indicating
system interruptions or malfunctions. Any interruption or malfunction of the chlorine
dosing system that may have resulted in levels of chlorine that were inadequate for
achieving effective disinfection, or interruptions or malfunctions of the dechlorination
system that may have resulted in excessive levels of chlorine in the final effluent shall be
reported with the monthly DMRs. The report shall include the date and time of the
interruption or malfunction, the nature of the problem, and the estimated amount of time
that the reduced levels of chlorine or dechlorination chemicals occurred.
10. The monthly average limits for fecal coliform and Enterococcus are expressed as a
geometric mean. Fecal coliform and Enterococcus monitoring shall be conducted
concurrently with TRC monitoring.
11. In addition to the effluent limits for bacteria, MWRA is required to update the existing
Memorandum of Understanding (MOU) between the MWRA, the Massachusetts
Division of Marine Fisheries (MA Marine Fisheries) and the US Food and Drug
Administration (FDA) and implementation of the MOU and the attached monitoring plan
is required by the Draft Permit (See Footnote 11). The updated Plan shall follow the same
procedures and locations as documented in Attachments A & B of the MOU with the
addition of station N21, located over the mid-point of the diffuser. The updated MOU and
monitoring plan shall be submitted to the MA Marine Fisheries and the FDA for review
and signature. The signed MOU and attached monitoring plan shall be submitted to EPA
and MassDEP within 12 months of the effective permit. Enterococcus should also
continue to be monitored seasonally (April 1 through October 31) along with fecal
coliform to ensure that MA WQS for bacteria are met.
NPDES Permit No. MA0103284 2023 Draft Permit
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The Permittee shall report the results of the monthly ambient fecal coliform and
Enterococcus monitoring on their monthly DMRs for station N21. If the Bay is stratified
at the time of sampling, the Permittee shall sample at the surface and below the
pycnocline. If the Bay is not stratified, the Permittee should enter a NODI code = 9 for
the below pycnocline DMR line. The ambient fecal coliform bacteria and Enterococcus
monitoring results at the other sampling locations shall be submitted as an attachment to
the monthly DMR. If an adverse-conditions monitoring event occurs, MWRA shall
provide a letter summarizing the event and the sampling data collected as an attachment
to the monthly DMR. Any updates or changes in the Ambient Bacteria Monitoring Plan
shall be submitted to MA Marine Fisheries and the FDA for review. The signed MOU
and plan shall be submitted to EPA.
12. If the MA DMF and/or the FDA determines in writing that the fecal coliform bacteria
limit is inadequate to ensure protection of shellfish resources, and EPA concurs in
writing, then the Permittee shall meet the following limits:
Effluent Limitation Monitoring Requirements
Effluent
Characteristic
Average
monthly
Average
Weekly
Maximum
Daily
Measurement
Frequency
Sample
Type
Fecal Coliform
Bacteria,
(organisms/100 mL)
14 --- 28 3/Day Grab
13. Oil and grease shall be tested using EPA Method 1664-n-Hexane Extractable Material
(HEM; Oil and Grease) and Silica Gel Treated n-Hexane Extractable Material (SGT-
HEM; Non-polar Material) by Extraction and Gravimetry Revision A or Method 1664
Revision B.
The Permittee shall have no detectable discharge of oil and grease. Compliance shall be
measured at the minimum level (ML) of detection for the EPA approved test methods.
The oil and grease ML is 5 mg/L using EPA Method 1664 (Revisions A and B), where
the ML is the lowest point on the curve used to calibrate the test equipment for the
pollutant of concern. If EPA approves a method under 40 CFR Part 136 for either, oil and
grease that has a ML lower than 5 mg/L, the Permittee shall be required to use the
improved method.
14. Ammonia Nitrogen, Total Kjeldahl nitrogen and nitrate + nitrite samples shall be
collected concurrently. The results of these analyses shall be used to calculate both the
concentration and mass loadings of total nitrogen, as follows.
Total Nitrogen (mg/L) = Total Kjeldahl Nitrogen (mg/L) + Nitrate + Nitrite (mg/L)
Total Nitrogen (lb/day) = [(average monthly Total Nitrogen (mg/L) * total monthly
effluent flow (Millions of Gallons (MG)) / # of days in the month] * 8.34
NPDES Permit No. MA0103284 2023 Draft Permit
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15. Report in nanograms per liter (ng/L) for effluent and influent samples; report nanograms
per gram (ng/g) for sludge samples. Until there is an analytical method approved in 40
CFR Part 136 for PFAS, monitoring shall be conducted using Method 1633. Report in
NetDMR the results of all PFAS analytes required to be tested in Method 1633, as shown
in Attachment H. This reporting requirement for the listed PFAS parameters takes effect
the first full calendar quarter following six months after the effective date of the Permit.
16. Report in nanograms per liter (ng/L) for effluent and influent samples; report nanograms
per gram (ng/g) for sludge samples. Until there is an analytical method approved in 40
CFR Part 136 for Adsorbable Organic Fluorine, monitoring shall be conducted using
Method 1621. This reporting requirement takes effect the first full calendar quarter
following six months after the effective date of the Permit.
17. The Permittee shall conduct acute toxicity tests (LC50) and chronic toxicity tests (C-
NOEC) in accordance with test procedures and protocols specified in Attachment C and
D of this Permit. LC50 and C-NOEC are defined in Part II.E. of this Permit. The
Permittee shall perform an acute toxicity test using the Inland Silverside ( Menidia
beryllina ) and Mysid Shrimp ( Mysidopsis bahia ). The Permittee shall perform a chronic
toxicity test using the 1-hour fertilization test with the Sea Urchin ( Arbacia punctulata ) in
accordance with the test procedures and protocols specified in Attachment D . Toxicity
test samples shall be collected during the same weeks each time of calendar quarters
ending March 31st, June 30th, September 30th, and December 31st. The complete report
for each toxicity test shall be submitted as an attachment to the DMR submittal which
includes the results for that toxicity test.
18. For Part I.A.1., Whole Effluent Toxicity Testing, the Permittee shall conduct the analyses
specified in Attachment C and D , Part VI. CHEMICAL ANALYSIS for the effluent
sample. If toxicity test(s) using the receiving water as diluent show the receiving water to
be toxic or unreliable, the Permittee shall follow procedures outlined in Attachment C
and D , Section IV., DILUTION WATER. Minimum levels and test methods are
specified in Attachment C and D , Part VI. CHEMICAL ANALYSIS.
19. For Part I.A.1., Ambient Characteristic, the Permittee shall conduct the analyses specified
in Attachment C and D , Part VI. CHEMICAL ANALYSIS for the receiving water
sample collected as part of the WET testing requirements. Such samples shall be taken
from the receiving water at a point immediately outside of the permitted discharge’s zone
of influence at a reasonably accessible location, as specified in Attachment C and D .
Minimum levels and test methods are specified in Attachment C and D , Part VI.
CHEMICAL ANALYSIS.
20. Monitoring and reporting for dissolved organic carbon (DOC) are not requirements of the
Whole Effluent Toxicity (WET) tests but are additional requirements. The Permittee may
analyze the WET samples for DOC or may collect separate samples for DOC
concurrently with WET sampling.
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21. A pH and temperature measurement shall be taken of each receiving water sample at the
time of collection and the results reported on the appropriate DMR. These pH and
temperature measurements are independent from any pH and temperature measurements
required by the WET testing protocols.
22. Sludge sampling shall be as representative as possible based on guidance found at
https://www.epa.gov/sites/production/files/2018-11/documents/potw-sludge-sampling-
guidance-document.pdf .
NPDES Permit No. MA0103284 2023 Draft Permit
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Part I.A., continued.
2. The discharge shall not cause a violation of the water quality standards of the receiving
water.
3. The discharge shall be free from pollutants in concentrations or combinations that, in the
receiving water, settle to form objectionable deposits; float as debris, scum or other matter to
form nuisances; produce objectionable odor, color, taste or turbidity; or produce undesirable
or nuisance species of aquatic life.
4. The discharge shall be free from pollutants in concentrations or combinations that adversely
affect the physical, chemical, or biological nature of the bottom.
5. The discharge shall not result in pollutants in concentrations or combinations in the receiving
water that are toxic to humans, aquatic life, or wildlife.
6. The discharge shall be free from floating, suspended and settleable solids in concentrations or
combinations that would impair any use assigned to the receiving water.
7. The discharge shall be free from oil and grease and petrochemicals.
8. The Permittee must provide adequate notice to EPA and MassDEP of the following:
a. Any new introduction of pollutants into the POTW from an indirect discharger
which would be subject to Part 301 or Part 306 of the Clean Water Act if it were
directly discharging those pollutants or in a primary industry category ( See 40 CFR
Part 122 Appendix A as amended) discharging process water; and
b. Any substantial change in the volume or character of pollutants being introduced
into that POTW by a source introducing pollutants into the POTW at the time of
issuance of the Permit.
c. For purposes of this paragraph, adequate notice shall include information on:
(1) The quantity and quality of effluent introduced into the POTW; and
(2) Any anticipated impact of the change on the quantity or quality of effluent
to be discharged from the POTW.
9. Pollutants introduced into the POTW by a non-domestic source (user) shall not pass through
the POTW or interfere with the operation or performance of the POTW.
10. In accordance with 40 CFR § 122.44(j)(1) the Permittee must identify, in terms of character
and volume, any Significant Industrial Users (SIUs) discharging into the POTW subject to
Pretreatment Standards under section 307(b) of CWA and 40 CFR Part 403. SIUs
information shall be updated at a minimum of once per year or at that frequency necessary to
NPDES Permit No. MA0103284 2023 Draft Permit
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ensure that all SIUs are properly permitted and/or controlled. The records shall be maintained
and updated as necessary.
B. COMBINED SEWER OVERFLOWS (CSOs)
1. Beginning on the effective date, the Permittee, MWRA, and the CSO-responsible Co-
permittees: Boston Water and Sewer Commission (BWSC), City of Cambridge, City of
Chelsea, and City of Somerville, are authorized to discharge stormwater/wastewater from the
combined sewer overflow (CSO) outfalls listed in Attachment A into the designated
receiving waters. These discharges are authorized only during “wet weather’ defined as any
period in which there is greater than 0.1 inches of rain and /or snow melt.
2. The effluent discharged from these CSO outfalls is subject to the following limitations:
a. The discharges shall not cause or contribute to violations of federal or state Water
Quality Standards.
b. The discharges shall receive treatment at a level providing 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. The EPA has made a Best Professional
Judgment (BPJ) determination that BPT, BCT, and BAT for combined sewer
overflow (CSO) control includes the implementation of Nine Minimum Controls
(NMC) specified below. These Nine Minimum Controls and the Nine Minimum
Controls Implementation Levels which are detailed further in Part I.B.2. are
requirements of this Permit and include:
(1) Proper operation, and regular maintenance programs for the sewer system,
and the CSOs.
(2) Maximum use of the collection system for storage of combined
wastewater and stormwater in order to minimize CSO discharges.
(3) Review and, as appropriate, modify the pretreatment program to minimize
the adverse effects of CSO outfall discharges.
(4) Maximization the proportion of the system’s wastewater, and combined
wastewater/stormwater, flow that is conveyed to the POTW for treatment.
(5) Dry weather overflows from CSO outfalls are prohibited and must be
eliminated.
(6) Minimize the discharge of solid and floatable materials in CSO outfall
discharges.
NPDES Permit No. MA0103284 2023 Draft Permit
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(7) Implement pollution prevention programs that focus on contaminant
reduction activities.
(8) Provide adequate notice to the public of CSO outfall occurrences and CSO
outfall impacts.
(9) Monitor to effectively characterize CSO outfall impacts and the efficacy
of CSO controls.
c. The authorized typical year discharge activations and volumes for the Boston Inner
Harbor CSO outfalls are limited as shown in Attachment I . Discharge frequencies
and volumes are expected to vary from year to year as a function of rainfall.
d. The authorized typical year discharge activations and volumes for the Charles
River CSO outfalls are limited as shown in Attachment I . Discharge frequencies
and volumes are expected to vary from year to year as a function of rainfall. CSO
outfalls discharging to the Charles River Basin have been granted a variance under
the Massachusetts Water Quality Standards (WQS) through August 31, 2024. A
copy of this determination letter for the variance extension is included as
Attachment J . The conditions of this variance are incorporated into and are
enforceable elements of this permit.
e. The authorized typical year discharge activations and volumes for the Alewife
Brook and Upper Mystic River CSO outfalls are limited as shown in Attachment
I . Discharge frequencies and volumes are expected to vary from year to year as a
function of rainfall. CSO outfalls discharging to the Alewife Brook/Upper Mystic
River Basin have been granted a variance under the Massachusetts Water WQS
through August 31, 2024. A copy of this determination letter for the variance
extension is included as Attachment K . The conditions of this variance are
incorporated into and are enforceable elements of this Permit.
f. The Permit’s discharges must meet federal and state WQS subject to and
consistent with any water quality standards variances or variance extensions issued
by MassDEP and approved by EPA.
3. Nine Minimum Controls Implementation Levels
The Permittee, MWRA, and CSO-responsible Co-permittees: BWSC, City of Cambridge,
City of Chelsea and City of Somerville, shall continue to implement the Nine Minimum
Control Program (NMC) in accordance with the documentation provided to EPA and
MassDEP or as subsequently modified to enhance the effectiveness of controls. This
implementation must include the controls identified in Part I.B.2.b.1-9 of this Permit plus
other controls the Permittee and CSO-responsible Co-permittees can reasonably
undertake as set forth in the documentation. Within 1 year of the effective date of the
NPDES Permit No. MA0103284 2023 Draft Permit
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permit, the Permittee and CSO-responsible Co-permittees shall submit to EPA and
MassDEP through NetDMR an updated NMC program.
a. Each CSO structure/regulator, pumping station and/or tide gate shall be routinely
inspected to ensure that they are in good working condition and adjusted to
minimize combined sewer discharges and tidal surcharging. Such inspections shall
occur monthly unless EPA approves a site-specific inspection program which has
been determined by EPA to provide an equal level of effectiveness (NMC #1, 2
and 4).
b. The following inspection results shall be recorded: the date and time of the
inspection, the general condition of the facility, and whether the facility is
operating satisfactorily. If maintenance is necessary, the Permittee or CSO-
responsible Co-permittees shall record: the description of the necessary
maintenance, the date the necessary maintenance was performed, and whether the
observed problem was corrected. The Permittee or CSO-responsible Co-permittee
shall maintain all records of inspections for at least three (3) years.
c. Annually, no later than March 31st , the Permittee and CSO-responsible Co-
permittees shall submit a certification to MassDEP and EPA which states that the
previous calendar year's monthly inspections were conducted, results recorded, and
records maintained.
d. MassDEP and EPA have the right to inspect any CSO-related structure or outfall at
any time without prior notification to the Permittee and CSO-responsible Co-
Permittees.
e. Discharges to the combined system of septage, holding tank wastes, or other
material which may cause a visible oil sheen or containing floatable material are
prohibited during wet weather when CSO outfalls may be active (NMC # 3, 6, and
7).
f. Dry weather overflows (DWOs) are prohibited (NMC #5). All dry weather
sanitary and/or industrial discharges from CSO outfalls must be reported to EPA
and MassDEP within 24 hours in accordance with the reporting requirements for
plant bypass (Paragraph D.1.e of Part II of this Permit).
g. The Permittee and CSO-responsible Co-permittees shall quantify and record all
discharges from combined sewer outfalls (NMC #9). Quantification shall be
through direct measurement or estimation. When estimating, the Permittee and
CSO-responsible Co-permittees shall make reasonable efforts, (i.e., gaging,
measurements) to verify the validity of the estimation technique. The following
information must be recorded for each combined sewer outfall for each discharge
event:
NPDES Permit No. MA0103284 2023 Draft Permit
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(1) Duration (hours) of discharge;
(2) Volume (gallons) of discharge; and
(3) National Weather Service precipitation data from the nearest gage where
precipitation is available at daily (24-hour) intervals and the nearest gage
where precipitation data at minimum of one-hour intervals is available to
the Permittee or CSO-responsible Co-permittees.
(4) A description of whether the discharge activation and volume are in
accordance with the MWRA Final CSO Facilities Plan or as amended.
h. Cumulative precipitation per discharge event shall be calculated.
i. The Permittee and CSO-responsible Co-permittees shall maintain all records of
discharges for at least six (6) years after the effective date of this Permit, as it is
collected, on an ongoing basis.
j. The Permittee and CSO-responsible Co-permittees shall install and maintain
identification signs for all combined sewer outfall structures (NMC # 8). The signs
must be located at or near the combined sewer outfall structures and be easily
readable by the public from the land and water. These signs shall be a minimum of
12 x 18 inches in size, with white lettering against a green background, and shall
contain the following information:
(1) For CSO outfalls where MWRA is the responsible Permittee:
WARNING:*
MASSACHUSETTS WATER RESOURCES AUTHORITY
WET WEATHER
SEWAGE DISCHARGE
OUTFALL (discharge serial number)
(2) For CSO outfalls where BWSC is the CSO-responsible Co-permittee:
WARNING:*
BOSTON WATER AND SEWER COMMISSION
WET WEATHER
SEWAGE DISCHARGE
OUTFALL (discharge serial number)
(3) For CSO outfalls where the City of Cambridge is the CSO-responsible Co-
permittee:
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WARNING:*
CITY OF CAMBRIDGE
DEPARTMENT OF PUBLIC WORKS
WET WEATHER
SEWAGE DISCHARGE
OUTFALL (discharge serial number)
(4) For CSO outfalls where the City of Chelsea is the CSO-responsible Co-
permittee:
WARNING:*
CITY OF CHELSEA
DEPARTMENT OF PUBLIC WORKS
WET WEATHER
SEWAGE DISCHARGE
OUTFALL (discharge serial number)
(5) For CSO outfalls where the City of Somerville is the CSO-responsible Co-
permittee:
WARNING:*
CITY OF SOMERVILLE
DEPARTMENT OF PUBLIC WORKS
WET WEATHER
SEWAGE DISCHARGE
OUTFALL (discharge serial number)
*For existing signs which otherwise meet the requirements of this section, the
word "Warning" need not be added.
Where easements over property not owned by the Permittee or CSO-responsible
Co-permittees must be obtained to meet this requirement, the Permittee or CSO-
responsible Co-permittees will use its best efforts to identify the appropriate
landowners and obtain the necessary easements, to the extent practicable.
The Permittee and CSO-responsible Co-permittees, to the extent feasible, shall
add a universal wet weather sewage symbol to each existing sign, or will place a
sign with a universal wet weather sewage symbol that is visible from the land and
water, unless there is already a warning sign written in a non-English language, or
will place additional signs in languages other than English based on notification
from the EPA. See Part I.K.3.
k. In accordance with 314 CMR 16.05(3), each Permittee and CSO-responsible Co-
permittee shall install and maintain signage at public access points to waters
NPDES Permit No. MA0103284 2023 Draft Permit
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affected by a potential discharge from the Permittee's or CSO-responsible Co-
permittee’s outfall by the date established in their approved CSO Public
Notification Plan. The locations for the signage shall be established in the
Permittee's or CSO-responsible Co-permittee’s approved CSO Public Notification
Plan based on consultation with boards of health or health departments in the
municipalities directly impacted by the discharge. Each sign shall identify:
(1) The existence of the outfall;
(2) The permittee;
(3) Information about weather events that may cause a discharge;
(4) A warning of the potential threat to public health by recreating in, or using
waters and shores affected by a discharge; and
(5) Information for the public to subscribe to notifications about discharges in
local area waters.
Signage shall be developed using a template provided by MassDEP and be able to
provide timely information about ongoing discharges to allow municipal boards of
health and health departments to meet the requirements of 314 CMR 16.09(5). For
discharges directly affecting neighborhoods identified as environmental justice
populations due to lacking English language proficiency, signage shall provide
access to translations in the language(s) most appropriate for those neighborhoods
and shall utilize universal symbols.
l. The City of Cambridge may use the activation of Outfall CAM401B as a general
indicator of the onset of CSO outfall discharges which would trigger the notice in
accordance with 314 CMR 16.00, Notification Requirements to Promote Public
Awareness of Sewage Pollution, unless there is evidence that a different CSO
outfall activated before CAM401B. (NMC #8).
m. Public Notification Plan
The Permittee and CSO-responsible Co-permittees must implement their preliminary and
final CSO Public Notification Plans as approved by MassDEP and shall meet all other
applicable requirements of 314 CMR 16.00. https://www.mass.gov/doc/314-cmr-1600-
notification-requirements-to-promote-public-awareness-of-sewage-pollution-1/download
4. The Permittee and each CSO-responsible Co-permittee may consolidate CSO reports which
are on similar reporting schedules.
5. Nine Minimum Controls Reporting Requirement
NPDES Permit No. MA0103284 2023 Draft Permit
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a. Annually, no later than April 30th , the Permittee and each CSO-responsible Co-
permittees shall submit a report into NetDMR which includes the following
information:
b. Activation frequency and discharge volumes for each CSO outfall listed on
Attachment A during the previous calendar year. For each day of an MWRA CSO
discharge event, the MWRA Report shall include the daily flow at DITP and note
whether there was a bypass of secondary treatment, and the volume bypassed.
c. For any Permittee or CSO-responsible Co-permittees with CSO treatment
facilities, a compilation of the data for CSO events for which sampling was
conducted pursuant to section I.B.6 of this Permit.
d. Precipitation during the previous year for each day, including total rainfall, peak
intensity, and average intensity.
e. Status of the implementation of CSO outfall abatement work for which the
Permittee or CSO-responsible Co-permittees is directly responsible in accordance
with the MWRA Final CSO Facilities Plan, the Federal Court Order, as amended
and any related subsequent documents and the requirements of a CSO Variance.
The authorized typical year CSO discharge activations and volumes can be found
in Attachment I .
f. For the outfalls listed in Attachment A , provide the following information in the
Annual Report for year 3 and every two years thereafter using the updated MWRA
model (or equivalent) for comparison:
(1) A comparison between the precipitation for the previous year and the
precipitation in the typical year under future planned conditions used in
the MWRA Final CSO Facilities Plan or “Notice of Project Change”
document, or subsequent document, whichever is appropriate. This
comparison shall include the number of events and size of events
(including recurrence interval).
i. For each CSO outfall, a comparison between the activation
volume and frequency for the previous year and the volume
and frequency expected during a typical year under future
planned conditions.
ii. For each CSO event, an estimate of the recurrence interval of
the storm event, using the rainfall data collected and the
information included in the NOAA Atlas 14, or other technical
reference for defining storm event recurrence.
NPDES Permit No. MA0103284 2023 Draft Permit
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iii. An evaluation of whether the CSO outfall activation volumes
and frequencies for the previous year are in accordance with
the estimates in the MWRA Final CSO Facilities Plan or as
amended by the Court, given the precipitation which occurred
during the year, and the CSO outfall abatement activities which
have been implemented. Where CSO outfall discharges are
determined to be greater than the activation frequency or
volume in either document above, the Permittee or CSO-
responsible Co-permittees shall include their assessment of
such result, a discussion of remaining CSO outfall abatement
activities and an assessment of the impact of those projects on
attaining the level of CSO outfall control identified in the
relevant document, or any amendments thereto.
6. Combined Sewer Overflow Outfall Monitoring
For each combined sewer overflow outfall listed in Attachment A of this Permit, the
Permittee or CSO-responsible Co-permittees must monitor the following for their outfalls:
Parameters
Reporting
Requirements Monitoring Requirements
Total Monthly Measurement
Frequency
Sample
Type
Total Flow Report Gallons Daily, when
discharging Continuous
Total Flow Duration (Duration of
flow through CSO discharge) Report Hours Daily, when
discharging Continuous
Number of CSO Discharge Events Report Monthly
Count
Daily, when
discharging Count
a. For Total Flow, measure the total flow discharged from each CSO outfall during
the month. For Total Flow Duration, report the total duration (hours) of discharges
for each CSO outfall during the month.
b. For those months when a CSO discharge does not occur, the Permittee and
responsible Co-permittees must indicate "no discharge" for the outfall for which
data was not collected.
c. This information shall be submitted with the annual report required by Part I.B.5 of
this Permit.
7. Combined Sewer Overflow Outfalls Limitations and Monitoring for the MWRA CSO
Treatment Facilities (Outfalls MWR201, MWR203, MWR205, MWR205A and MWR215)
NPDES Permit No. MA0103284 2023 Draft Permit
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a. In addition to the requirements for all CSO outfalls listed above, during the period
beginning on the effective date, the Permittee is authorized to discharge treated
effluent through Outfalls MWR201, MWR203, MWR205, MWR205A and
MWR215. Outfalls MWR201 and MWR205A discharge to Class B waters with
CSO variances. Outfalls MWR203, MWR205 and MWR215 discharge into Class
SB(CSO) waters. These discharges are authorized only during wet weather (i.e.,
any period in which there is greater than 0.1 inches of rain and/or snow melt). The
discharge shall be limited and monitored as specified below; the receiving water
and the influent shall be monitored as specified below.
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b. CSO Effluent Limits
Effluent Characteristic
Effluent Limitation Monitoring
Requirements 22,23,24
Average
Monthly
Maximum
Daily
Measurement
Frequency
Sample
Type 25
Flow 26 Report Report Per Discharge
Event Recorder
Rainfall/Precipitation 27 Report Report Per Discharge
Event
Total
BOD5
Outfalls MWR201, MWR205A, MWR203,
MWR205, MWR215
Report mg/L and
lb/day
Report mg/L and
lb/day
4/Year 28 Event
Composite
TSS
Outfalls MWR201, MWR205A, MWR203,
MWR205, MWR215
Report mg/L and
lb/day
Report mg/L and
lb/day
4/Year 28 Event
Composite
pH Range 29
Outfalls MWR201, MWR205A
Outfalls MWR203, MWR205, MWR215
6.5 - 8.3 S.U.
6.5 - 8.5 S.U. 4/Year 28 Grab
Total Residual Chlorine 30
Outfall MWR201
Outfall MWR203
Outfall MWR205
Outfall MWR205A
Outfall MWR215
0.055 mg/L
0.045 mg/L
0.075 mg/L
0.01 mg/L
0.015 mg/L
0.1 mg/L
0.078 mg/L
0.13 mg/L
0.02 mg/L
0.026 mg/L
4/Year 28 Grab
E. coli 30
Outfalls MWR201, MWR205A 126 cfu/100 mL 410 cfu/100 mL 4/Year 28 Grab
NPDES Permit No. MA0103284 2023 Draft Permit
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Effluent Characteristic
Effluent Limitation Monitoring
Requirements 22,23,24
Average
Monthly
Maximum
Daily
Measurement
Frequency
Sample
Type 25
Enterococcus 30
Outfalls MWR203, MWR205 and MWR215 35 cfu/100 mL 130 cfu/100 mL 4/Year 28 Grab
NPDES Permit No. MA0103284 2023 Draft Permit
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Whole Effluent Toxicity (WET) Testing
LC50
Outfalls MWR201, MWR205A 31,32
Outfalls MWR203, MWR205, MWR215 33,34 Report
Report
Report
Report
2/Year Event
Composite
Salinity
Outfalls MWR203, MWR205, MWR215 --- Report ppt 2/Year Event
Composite
Ammonia Nitrogen --- Report mg/L 2/Year Event
Composite
Total Cadmium --- Report mg/L 2/Year Event
Composite
Total Copper --- Report mg/L 2/Year Event
Composite
Total Nickel --- Report mg/L 2/Year Event
Composite
Total Lead --- Report mg/L 2/Year Event
Composite
Total Zinc --- Report mg/L 2/Year Event
Composite
Total Organic Carbon --- Report mg/L 2/Year Event
Composite
NPDES Permit No. MA0103284 2023 Draft Permit
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Footnotes:
22. All samples shall be collected in a manner to yield representative data. A routine
sampling program shall be developed in which samples are taken at the same
location, and same time frame. Occasional deviations from the routine sampling
program are allowed, but the reason for the deviation shall be documented as an
electronic attachment to the applicable discharge monitoring report. The Permittee
shall report the results to the EPA and MassDEP of any additional testing above
that required herein, if testing is in accordance with 40 CFR Part 136.
23. In accordance with 40 CFR § 122.44(i)(1)(iv), the Permittee shall monitor
according to sufficiently sensitive test procedures (i.e., methods) approved under
40 CFR Part 136 or required under 40 CFR chapter I, subchapter N or O, for the
analysis of pollutants or pollutant parameters (except WET). A method is
“sufficiently sensitive” when: 1) The method minimum level (ML) is at or below
the level of the effluent limitation established in the permit for the measured
pollutant or pollutant parameter; or 2) The method has the lowest ML of the
analytical methods approved under 40 CFR Part 136 or required under 40 CFR
chapter I, subchapter N or O for the measured pollutant or pollutant parameter.
The term “minimum level” refers to either the sample concentration equivalent to
the lowest calibration point in a method or a multiple of the method detection
limit (MDL), whichever is higher. Minimum levels may be obtained in several
ways: They may be published in a method; they may be based on the lowest
acceptable calibration point used by a laboratory; or they may be calculated by
multiplying the MDL in a method, or the MDL determined by a laboratory, by a
factor.
24. When a parameter is not detected above the ML, the Permittee must report the
data qualifier signifying less than the ML for that parameter (e.g., < 50 μ g/L, if
the ML for a parameter is 50 μ g/L). For reporting an average based on a mix of
values detected and not detected, assign a value of "0" to all non-detects for that
reporting period and report the average of all the results.
25. A "grab" sample, for the purposes of this section, is an individual sample
collected in a period of less than 15 minutes. A grab sample will be taken within
the first two hours of the start of a discharge, and every hour thereafter for the
duration of the discharge.
A "composite" sample, for the purposes for this section, is a time-weighted
composite sample. Sampling will begin within the first two hours of the start of a
discharge and aliquots taken no more than one hour apart for the duration of the
discharge, not to exceed twenty-four (24) hours. The aliquots will be of equal
NPDES Permit No. MA0103284 2023 Draft Permit
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volume, comprising a time-weighted composite as defined in Part II Standard
Conditions.
26. Report the peak flow rate, duration and volume for each discharge event.
27. Report the National Weather Service data for Boston per discharge event. Report
intensity, duration and volume of each rain event.
28. Sampling shall be concentrated during the “critical” use periods. The Permittee
shall sample one Spring event (March 1st – April 30th), two Summer events (May
1st – August 31st) and one Fall event (September 1st – October 31st). At least one
of the sampled events shall include a period of discharge from MWR205A. The
Permittee shall report “9” on its DMR during months when sampling is not
conducted.
29. The pH shall be within the specified range at all times. The minimum and
maximum pH sample measurement values for the month shall be reported in
standard units (S.U.).
30. The Permittee shall minimize the use of chlorine while maintaining adequate
bacterial control. Monitoring for total residual chlorine (TRC) is only required for
discharges which have been previously chlorinated, or which contain residual
chlorine.
TRC samples must be collected concurrently with the E.coli and/or Enterococcus
samples.
Chlorination and dechlorination systems shall include an alarm system for
indicating system interruptions or malfunctions. Any interruption or malfunction
of the chlorine dosing system that may have resulted in levels of chlorine that
were inadequate for achieving effective disinfection, or interruptions or
malfunctions of the dechlorination system that may have resulted in excessive
levels of chlorine in the final effluent shall be reported with the monthly DMRs.
The report shall include the date and time of the interruption or malfunction, the
nature of the problem, and the estimated amount of time that the reduced levels of
chlorine or dechlorination chemicals occurred.
Process Control TRC: For each discharge event, the Permittee must maintain a
record of process control TRC before dechlorination, using the TRC analyzer
(measured continuously) or with hourly grab samples).
The discharge event maximum is the hourly maximum during the discharge event.
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31. The Permittee shall conduct acute toxicity tests (LC50) two times per year, once
in Quarter 2 (April 1 - June 30), and once in Quarter 3 (July 1 - Sep 30). The
LC50 is defined in Part II.E. of this Permit. The Permittee shall perform an acute
toxicity test using the daphnid ( Ceriodaphnia dubia ) and the fathead minnow
( Pimephales promelas ). Toxicity test samples shall be collected during the first
flush or as a composite over the duration of the overflow, not to exceed 24 hours.
The tests must be performed in accordance with test procedures and protocols
specified in Attachment E of this Permit.
If the discharge fails an LC50 = 100% toxicity test, the Permittee will perfo rm a
second acute toxicity test within 30 days, or if weather does not permit, as soon as
possible. If the discharge fails the second LC50 = 100% toxicity test, the
Permittee will submit a report to EPA discussing the results of the first two
toxicity tests and the concomitant priority pollutant testing.
The complete report for each toxicity test shall be submitted as an attachment to
the DMR submittal which includes the results for that toxicity test.
32. For Part I.B.6., Whole Effluent Toxicity Testing, the Permittee shall conduct the
analyses specified in Attachment E , Part VI. CHEMICAL ANALYSIS for the
effluent sample. If toxicity test(s) using the receiving water as diluent show the
receiving water to be toxic or unreliable, the Permittee shall follow procedures
outlined in Attachment E , Section IV., DILUTION WATER. Minimum levels
and test methods are specified in Attachment E , Part VI. CHEMICAL
ANALYSIS.
33. The Permittee shall conduct acute toxicity tests (LC50) two times per year, once
in Quarter 2 (April 1 - June 30), and once in Quarter 3 (July 1 - Sep 30). The
LC50 is defined in Part II.E. of this Permit. The Permittee shall perform an acute
toxicity test using the Inland Silverside ( Menidia beryllina ) and Mysid Shrimp
( Mysidopsis bahia ) in accordance with test procedures and protocols specified in
Attachment C of this Permit. The Permittee shall perform a chronic toxicity test
using the 1-hour fertilization test with the Sea Urchin ( Arbacia punctulata ) in
accordance with test procedures and protocols specified in Attachment D of this
Permit. . Toxicity test samples shall be collected during the first flush or as a
composite over the duration of the overflow, not to exceed 24 hours.
34. The complete report for each toxicity test shall be submitted as an attachment to
the DMR submittal which includes the results for that toxicity test. For Part I.B.6.,
Whole Effluent Toxicity Testing, the Permittee shall conduct the analyses
specified in Attachments C and D , Part VI. CHEMICAL ANALYSIS for the
effluent sample. If toxicity test(s) using the receiving water as diluent show the
receiving water to be toxic or unreliable, the Permittee shall follow procedures
NPDES Permit No. MA0103284 2023 Draft Permit
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outlined in Attachments C and D , Section IV., DILUTION WATER. Minimum
levels and test methods are specified in Attachment C and D , Part VI.
CHEMICAL ANALYSIS.
C. UNAUTHORIZED DISCHARGES
1. This Permit authorizes discharges only from the outfalls listed in Part I.A.1, Attachment A
and Part I.B.1 in accordance with the terms and conditions of this Permit. Discharges of
wastewater from any other point sources, including sanitary sewer overflows (SSOs), are not
authorized by this Permit. The Permittee, CSO-responsible Co-permittees and Co-permittees
must provide verbal notification to EPA and MassDEP within 24 hours of becoming aware of
any unauthorized discharge and a written report within 5 days, in accordance with Part
II.D.1.e (24-hour reporting). Providing that it contains the information required in Part
II.D.1.e, submission of the MassDEP SSO Reporting Form (described in I.C.3 below) may
satisfy the requirement for a written report. See Part I.J below for reporting requirements.
2. The Permittee, CSO-responsible Co-permittees and Co-permittees must provide notification
to the public within 24 hours of becoming aware of any unauthorized discharge, except SSOs
that do not impact a surface water or the public, on a publicly-available website, and it shall
remain on the website for a minimum of 12 months. Such notification shall include the
location (including latitude and longitude) and description of the discharge; estimated
volume; the period of noncompliance, including exact dates and times, and, if the
noncompliance has not been corrected, the anticipated time it is expected to continue.
3. Written notification of SSOs to MassDEP shall be made on its SSO Reporting Form (which
includes MassDEP Regional Office telephone numbers). The reporting form and instruction
for its completion may be found on-line at https://www.mass.gov/how-to/sanitary-sewer-
overflowbypassbackup-notification . For SSOs and discharges of partially treated wastewater
that are defined in 314 CMR 16.03, the Permittee, CSO-responsible Co-permittees, and Co-
permittees must meet all requirements of 314 CMR 16.00, including, but not limited to,
public notification within two hours of discovery of the discharge, reporting into MassDEP’s
electronic reporting system, and posting on the Permittee’s, CSO-responsible Co-permittee’s,
or Co-permittee’s website.
4. Bypassing of wastewater flows is not authorized. Bypass is subject to enforcement discretion
in situations where determined necessary to prevent loss of life or damage to the plant. The
Clean Water Act ("CWA") and EPA's 1994 CSO Control Policy state that the intentional
diversion of waste streams from any portion of a treatment facility, including secondary
treatment, is a bypass. EPA regulations at 40 CFR 122.41 (m) further detail the conditions
under which EPA will not initiate an enforcement action for bypasses, including: (1) that the
bypass was unavoidable to prevent loss of life, personal injury, or severe property damage;
and (2) there were no feasible alternatives to the bypass. Reporting of secondary bypass
events shall be carried out as set forth in provisions of Section I.A.1, Footnote 6 of this
permit.
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D. NOTICE OF ELIMINATION
The Permittee and CSO-responsible Co-permittees shall give notice of elimination or change in
status of any CSO outfall listed in Attachment A as soon as possible in writing to EPA and
MassDEP.
E. OPERATION AND MAINTENANCE
1. Wastewater Treatment Facility 2
Operation and maintenance (O&M) of the wastewater treatment facility owned and/or operated
by the Permittee shall be in compliance with 40 CFR § 122.41 (d) and (e) and the terms and
conditions of the Part II. Standard Conditions, B. Operation and Maintenance of Pollution
Controls which is attached to this Permit.
a. WWTF Major Storm and Flood Events Plan. Within 12 months of the effective date of
this Permit, the Permittee shall develop and submit a WWTF Major Storm and Flood
Events Plan and begin to implement mitigation measures consistent with the schedule
contained in this paragraph. The Plan shall contain three components: (1) an asset
vulnerability evaluation, (2) a systemic vulnerability evaluation 3 of the assets, and (3)
a mitigation measures alternatives analysis. The Plan shall include resiliency and
implementation planning informed by an evaluation of all WWTF vulnerabilities to
major storm and flood events. 4 The planning process shall be iterative, and re-
evaluations shall be conducted: (1) if on- or off-site structures are added, removed or
significantly changed in any way that will impact the vulnerability of the WWTF; and
(2) as data sources used for such evaluations are revised, or generated. At a minimum,
the Plan must take future conditions into consideration, specifically the midterm (i.e.,
2 Wastewater Treatment Facility means any devices and systems used in the storage, treatment, recycling and
reclamation of municipal sewage or industrial wastes of a liquid nature. It does not include sewers, pipes and other
conveyances to the wastewater treatment facility.
3 To determine the vulnerabilities to the facilities from major storm and flood events, you must conduct the
evaluation using, at a minimum, the worst-case data relating to changes in precipitation, sea level rise, extreme
weather events, coastal flooding, inland flooding, sewer flow and inflow and infiltration and relevant to the facilities
from: 1) the data generated by the 13 federal agencies that conduct or use research on global change that contributed
to the latest National Climate Assessment produced by the U.S. Global Change Research Program (USGCRP); 2)
climate data generated by the Commonwealth of Massachusetts; and 3) resiliency planning completed by the
municipality in which a given facility is located (i.e., City of Boston) and incorporate the results of the evaluation in
a manner that demonstrates that the control measures taken are precautionary and sufficiently protective. Evaluation
must be completed by a qualified person on a five-year basis considering: 1) historical observations from all years
the Permittee has operated the facility prior to this permit’s term; 2) set midterm (i.e., 20-30 years) and long-term
(i.e., 80-100 years) ranges.
4 “Major storm and flood events” refer to instances resulting from major storms such as hurricanes, extreme/heavy
precipitation events, and pluvial, fluvial, and flash flood events such as high-water events, storm surge, and high-tide
flooding. “Extreme/heavy precipitation” refers to instances during which the amount of rain or snow experienced in
a location substantially exceeds what is normal. What constitutes a period of heavy precipitation varies according to
location and season. “Extreme/heavy precipitation” does not necessarily mean the total amount of precipitation at a
location has increased, but just that precipitation is occurring in more intense or more frequent events.
NPDES Permit No. MA0103284 2023 Draft Permit
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20-30 years) and long-term (i.e., 80-100 years) and, in the case of sea level change, the
plan must consider extreme sea level change. The Plan shall be updated at least every
five (5) years from the effective date of this Permit and must take future conditions
into consideration. 5
(1) Component 1: Asset Vulnerability Evaluation . This first component of the
WWTF Major Storm and Flood Events Plan must assess the vulnerability of
individual WWTF-related assets. The Permittee may find EPA’s guide:
Flood Resilience: A Basic Guide for Water and Wastewater Utilities 6 and
EPA’s website 7 Creating Resilient Water Utilities (CRWU) helpful for
completing this component.
The Asset Vulnerability Evaluation shall include, at a minimum, the
following:
i. Description of planning priorities related to major storm and
flood event vulnerabilities presented by the location of the
WWTF (e.g., proximity to waterbodies which may cause
flooding).
ii. Identification of all assets related to the WWTF (e.g.,
buildings, laboratories and offices, WWTF, septage collection
facilities, etc.), the elevation of each asset, and if the asset falls
into the 100-year flood map or the 500-year flood map; 8
iii. Description of structural improvements, either completed or
planned, and/or other mitigation measures 9 designed to
minimize 10 the impacts of major storm and flood events to each
specific asset identified above.
The Permittee shall consider, at a minimum, the following measures:
5 It will be advantageous to the Permittee to consider low, medium, high and extreme levels of sea level change to
determine priority assets and plan for increasingly protective mitigation measures.
6 https://www.epa.gov/sites/default/files/2015-08/documents/flood_resilience_guide.pdf
7 https://www.epa.gov/crwu
8 See https://www.epa.gov/sites/default/files/2015-08/documents/flood_resilience_guide.pdf for a basic guide to
flood resiliency for water and wastewater utilities.
9 Mitigation measure can be, for example, an emergency planning activity, equipment modification/upgrade or new
capital investment/construction project.
10 For the purposes of this provision, the term “minimize” means to reduce and/or eliminate to the extent achievable
the impacts to the facilities.
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(a) Construction of flood barriers to protect infrastructure or
reinforce existing structures to withstand flooding and
additional exertion of force;
(b) Establish remote locations for operations, equipment, records
and data backups;
(c) Plan and establish alternative or on-site power supply; 11
(d) Relocate facilities and/or infrastructure to higher elevations;
(e) Catalog emergency resources used during a major storm or
flood event;
(f) Develop emergency response plans;
(g) Establish contracts for backup supplies of critical chemicals;
(h) Establish mutual aid agreements with neighboring utilities;
(i) Integrate long-term risks into capital improvement plans;
(j) Participate in community planning and regional
collaborations;
(k) Conduct staff training for implementing your emergency
procedures at regular intervals;
(l) When designing new or replacement facilities, strive to locate
facilities above the relative base flood elevation 12 for both the
1% (100 - year) and 0.2 % (500 -year) chance storm events.
iv. Identify the source of data used to assess vulnerabilities to
major storm and flood events.
v. Identify potential funding sources 13 for resilience planning and
implementation. (e.g., EPA, FEMA, MassDEP, capital
planning, etc.).
(2) Component 2: Systemic Vulnerability Evaluation . Upon completing
assessment of the vulnerabilities of individual assets, the Permittee shall
evaluate the vulnerability of its WWTF system as a whole. This second
component of the evaluation shall include, at a minimum, a systematic
11 The Permittee shall clearly document measures taken specifically to manage energy system disruptions, such as a
general power outage, as well as document whether and, if so, to what extent, power supply adequate to ensure safe
and reliable operations of the facility is threatened during a major storm or flood. They shall clearly document
measures that have been taken to address any risks the facility faces of losing power during a major storm or flood in
a manner that could result in environmental or public health impacts.
12 For activities proposed for MA facilities within Areas Subject to Protection under M.G.L. c. 131, § 40 or the 100-
foot buffer zone, the Base Flood Elevation is defined at 310 CMR 10.04, Definitions of Special Flood Hazard Area,
Velocity Zone, and Coastal High Hazard Area, Land Subject to Coastal Storm Flowage at 310 CMR 10.36 and
Bordering Land Subject to Flooding, and Isolated Land Subject to Flooding at 310 CMR 10.57. Also refer to the
Massachusetts State Building Code for any other required standards related to Base Flood Elevation.
13 See https://www.epa.gov/fedfunds
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vulnerability evaluation for each asset identified in Part I.E.1.a.(1),
including the following:
i. Define the criticality of the asset to overall treatment facility
operations. 14
ii. Identify the highest 15 priority assets for the facility/system and
the measures taken (or planned) to reduce facility vulnerability
to risks that could degrade overall system operations in a
manner that would result in environmental or public health
impacts.
(3) Component 3: Mitigation Measures Alternatives Evaluation. Upon
completing assessment of the vulnerabilities of the WWTF system as a
whole, the Permittee shall provide an assessment of asset-specific
mitigation measures, and/or, if appropriate, combinations of mitigation
measures to minimize the impact of major storm and flood events. The
Permittee shall then select the most effective mitigation measure(s) and
include a schedule for implementation. This third component shall
include, at a minimum, the following:
i. An evaluation of mitigation measure alternatives including a
cost-effectiveness analysis and a review of technical,
environmental, and institutional factors.
ii. For each mitigation measure, quantitatively document
(including assumptions and methodologies) the residual risk
today, in the midterm (i.e., 20-30 years) and the long-term (i.e.,
80-100 years). The evaluation should include estimates of
which customers and geographic areas bear the residual risk
after implementation of the mitigation measures. Residual risk
is a term that refers to the risk remaining for an asset or system,
after mitigation measures are taken.
iii. Selection of mitigation measures to be undertaken, including:
14 For example, an asset like a pumping station or headworks is often scored “high” for criticality, as the safe and
reliable operation of many assets during a major storm or flood depend upon the continued operation of that
particular asset. If a pump station is degraded or fails, many other assets operations can degrade or fail, resulting in
environmental or public health impacts.
15 Based on the combined assessment of asset-level vulnerability today and in the midterm (i.e., 20-30 years) and
long-term (i.e., 80-100 years), the criticality of that asset’s performance to the operations of the system today and in
the midterm (i.e., 20-30 years) and long-term (i.e., 80-100 years).
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(a) a schedule 16 of implementation for each selected mitigation
measure; 17 and
(b) a map showing the location of planned mitigation measure.
(4) Annual Report . The Permittee shall submit an Annual Operation and
Maintenance Report on the WWTF Major Storm and Flood Events Plan
implementation and results for the prior calendar year including
documenting any changes to the WWTF or other assets that may impact
the current vulnerability evaluation. The first annual report is due the first
March 31 following submittal of the Wastewater Treatment Facility Major
Storm and Flood Events Plan and shall be included with the annual report
required in Part I.E.3. below.
2. Sewer System
Operation and maintenance (O&M) of the sewer system owned and operated, respectively, by
the Permittee, CSO-responsible Co-permittees: Boston Water and Sewer Commission (BWSC),
City of Cambridge, City of Chelsea and City of Somerville; and each of the Co-permittee
municipalities listed in Attachment B shall be in compliance with the terms and conditions of
Part C, Part D, Part E, Part F and Part J of this Permit and the General Requirements of Part II, of
this Permit for only its own infrastructure, activities and required reporting with respect to the
portions of the collection system that it owns or operates.
No Permittee shall be responsible for violations of Part C, Part D, Part E, Part F and Part J of this
Permit and/or the General Requirements of Part II committed by another Permittee relative to the
portions of the collection system owned and operated by such other Permittee. In the event of
any conflict between the above provisions and any other term or provision of this Permit, the
above provisions shall control. The Permittee and Co-permittees are required to complete the
following activities for the respective portions of the collection system which they operate:
16 In describing the schedule to implement mitigation measures, the Permittee shall clearly document which
mitigation measures identified in the Plan have or have not been integrated into that system’s capital planning
process. A mitigation measure is integrated when a budget line item in that system’s current and adopted capital plan
clearly identifies the year of completion and expenditure that has been budgeted and approved to complete that
mitigation measure.
17 For all measures considered, the Permittee must document in the Plan the factual basis (i.e., the maps, data sets
and calculations for the analysis), for either implementing or not implementing the measure. The factual basis and
analysis must be presented in sufficient detail to allow EPA, the public, or an independent qualified person to
evaluate the reasonableness of the decision. For measures already in place, including requirements from state, local
or federal agencies, a description of the measures and how they meet the requirement(s) of this Permit must be
documented in the Plan.
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a. Maintenance Staff
The Permittee, the CSO-responsible Co-permittees and Co-permittees shall provide an
adequate staff to carry out the operation, maintenance, repair, and testing functions required
to ensure compliance with the terms and conditions of this Permit that apply to the
Permittee, CSO-responsible Co-permittees, or Co-permittees. Provisions to meet this
requirement shall be described in the Sewer System O&M Plan required pursuant to Part
I.E.2.e below.
b. Preventive Maintenance Program
The Permittee, CSO-responsible Co-permittees and Co-permittees shall maintain an
ongoing preventive maintenance program to prevent overflows and bypasses caused by
malfunctions or failures of the sewer system infrastructure that each owns and operates.
The program shall include an inspection program designed to identify all potential and
actual unauthorized discharges. Plans and programs to meet this requirement shall be
described in the Sewer System O&M Plan required pursuant to Part I.E.2.e. below.
c. Infiltration/Inflow
(1) The Permittee, CSO-responsible Co-permittees and Co-permittees shall
control infiltration and inflow (I/I) into the sewer system as necessary to
prevent high flow related unauthorized discharges from their collection
systems and high flow related violations of the wastewater treatment
plant's effluent limitations. Plans and programs to control I/I shall be
described in the Sewer System O&M Plan required pursuant to Part
I.E.2.e. below.
(2) The Permittee, MWRA, shall update its existing I/I Reduction Plan. As
part of the update, the Permittee must identify the goals and strategies of
the 2002 Regional I/I Reduction Plan that have been completed and justify
the goal or strategy be removed from the updated Plan. Additionally, the
Permittee shall also consider new steps, strategies, and technologies to be
implemented in addressing I/I. Finally, the Permittee shall include a
discussion of historical SSO locations and upstream levels of I/I, with a
specific proposal including the use of new strategies and technologies to
reduce I/I in these contributing areas.
Specifically, for the portion of the regional sewer system operated by
MWRA, the MWRA shall update their existing Sanitary Sewer Overflow
Plan, now renamed Sanitary Sewer Overflow Mitigation Plan, and submit
to EPA and MassDEP within 1 year of the effective date of this Permit,
and begin implementing an effective and updated plan consisting of the
following:
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i. Identification of all SSO locations;
ii. A program for periodic inspection and monitoring of overflows
which occur during wet weather;
iii. Identification of all SSOs that occur as a result of operational
and maintenance deficiencies (e.g., sewer backups, pump
failures) and a plan for improved operation and maintenance to
prevent recurrences;
iv. Updated procedures for notification of potentially affected
entities (e.g., drinking water suppliers) and the public of
overflows that may endanger human health.
v. As part of the sewer system operation and maintenance plan
required in I.E.2.e for the portion of the regional sewer system
operated by the MWRA, which shall establish staffing and
operations procedures at MWRA pump stations, headworks
facilities, and at any critical conveyance structures (siphons,
CSO regulators/facilities), which shall encompass the following
goals:
(a) Maximizing conveyance of wastewater flows to Deer Island
for treatment and discharge;
(b) Optimizing use of MWRA collection and transport facilities to
manage any capacity restrictions and minimize risk of SSO
impacts to public drinking water supplies, primary contact
resource areas, or other areas where surcharging and/or
overflow conditions will result in serious public health
impacts; and
(c) At locations where SSO risk is significant, provisions for
preemptive and response actions to mitigate the potential
impacts of the discharge.
(3) The Draft Permit maintains the requirement for the Permittee, MWRA, to
submit an annual summary report ("Annual Infiltration and Inflow (I/I)
Reduction Report") of all actions taken to reduce I/I during the MWRA's
past fiscal year by September 1st of each year. The Report shall continue
to contain both estimated and actual Community Wastewater Flow
Components Estimates for each of the MWRA member communities
which shall be placed on the MWRA web page for public informational
purposes. The Community Wastewater Flow Components Estimates table
should differentiate between CSO and non-CSO communities.
(4) The Draft Permit also requires the Co-permittees to prepare and submit I/I
Reduction Plans. Massachusetts regulations at 314 CMR 12.04 (2)
required municipalities to submit I/I Analysis Reports to MassDEP.
NPDES Permit No. MA0103284 2023 Draft Permit
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Municipalities were then required to conduct Sewer System Evaluation
Surveys in accordance with their I/I Analysis Report. EPA notes that these
reports can be the basis for I/I Plans to be developed and submitted by the
Co-permittees to remove excessive I/I from the collection system that it
owns and/or operates as required in I.E.2.e below.
d. Sewer System Mapping
Within 30 months of the effective date of this Permit, the Permittee, CSO-responsible Co-
permittees and Co-permittees shall prepare a map of the sewer collection system it owns and
operates. The map shall be on a street map of the community, with sufficient detail and at a scale
to allow easy interpretation. The sewer system information shown on the map shall be based on
current conditions and shall be kept up-to-date and available for review by federal, state, or local
agencies upon request. Such map(s) shall include, but not be limited to the following:
1. All sanitary sewer lines and related manholes;
2. All combined sewer lines, related manholes, and catch basins;
3. All combined sewer regulators and any known or suspected connections between the
sanitary sewer and storm drain systems (e.g., combination manholes);
4. All connection points where Co-permittee collection systems connect to the Permittee-
owned collection system or the collection system of another community.
5. All outfalls, including the treatment plant outfall(s), CSOs, and any known or
suspected SSOs, including stormwater outfalls that are connected to combination
manholes;
6. All pump stations and force mains;
7. The wastewater treatment facility(ies);
8. All surface waters (labeled);
9. Other major appurtenances such as inverted siphons and air release valves;
10. A numbering system which uniquely identifies manholes, catch basins, overflow
points, regulators and outfalls;
11. The scale and a north arrow; and
12. The pipe diameter, date of installation, type of material, distance between manholes,
and the direction of flow.
e. Sewer System O&M Plan
The Permittee, CSO-responsible Co-permittees and Co-permittees shall develop and
implement a Sewer System O&M Plan for the portion of the system it owns and operates.
(1) Within six (6) months of the effective date of the Permit, the Permittee,
CSO-responsible Co-permittees, and Co-permittees shall submit to EPA
and the State:
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i. A description of the collection system management goals,
staffing, information management, and legal authorities;
ii. A description of the collection system and the overall condition
of the collection system including a list of all pump stations
and a description of recent studies and construction activities;
and
iii. A schedule for the development and implementation of the full
Sewer System Operation and Maintenance Plan including the
elements in Parts I.E.2.e.(3)(i) through (3)(ix) below.
(2) Within 12 months of the effective date of the Permit, the Permittee, CSO-
responsible Co-Permittees and Co-permittees shall develop and implement
a Sewer System Flood Events Plan as an element of the Sewer System
Operations and Maintenance Plan. The Plan shall contain three
components: (1) an asset vulnerability evaluation, (2) a systemic
vulnerability evaluation of the system and (3) an alternatives analysis. The
Plan shall include resiliency planning and implementation informed by an
evaluation 18 of all sewer system vulnerabilities to major storm and flood
events 19 . The planning process shall be iterative, and re-evaluations shall
be conducted; (1) if on- or off-site structures are added, removed or
significantly changed in any way that will impact the vulnerability of the
sewer system and (2) as data sources used for such evaluations are revised
or generated. At a minimum, the Plan must take future conditions into
consideration, specifically midterm (i.e., 20-30 years) and long-term (i.e.,
80-100 years) and, in the case of sea level change, the plan must consider
extreme sea level change. The Plan shall be updated every five (5) years
from the effective date of this Permit.
18 To determine the vulnerabilities to the facilities from major storm and flood events, you must conduct the
evaluation using, at a minimum, the worst-case data relating to changes in precipitation, sea level rise, extreme
weather events, coastal flooding, inland flooding, sewer flow and inflow and infiltration and relevant to the facilities
from: 1) the data generated by the 13 federal agencies that conduct or use research on global change that contributed
to the latest National Climate Assessment produced by the U.S. Global Change Research Program (USGCRP); 2)
climate data generated by the Commonwealth of Massachusetts; and 3) resiliency planning completed by the
municipality in which a given facility is located (i.e., City of Boston) and incorporate the results of the evaluation in
a manner that demonstrates that the control measures taken are precautionary and sufficiently protective. Evaluation
must be completed by a qualified person on a five-year basis considering: 1) historical observations from all years
the Permittee has operated the facility prior to this Permit’s term; 2) set midterm (i.e., 20-30 years) and long-term
(i.e., 80-100 years) ranges.
19 “Major storm and flood events” refer to instances resulting from major storms such as hurricanes, extreme/heavy
precipitation events, and pluvial, fluvial, and flash flood events such as high-water events, storm surge, and high-tide
flooding. “Extreme/heavy precipitation” refers to instances during which the amount of rain or snow experienced in
a location substantially exceeds what is normal. What constitutes a period of heavy precipitation varies according to
location and season. “Extreme/heavy precipitation” does not necessarily mean the total amount of precipitation at a
location has increased-just that precipitation is occurring in more intense or more frequent events.
NPDES Permit No. MA0103284 2023 Draft Permit
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i. Component 1: Asset Vulnerability Evaluation . The first
component of the Sewer System Operation and Maintenance
Plan must assess the vulnerability of individual sewer system-
related assets. The Permittee and Co-permittee may find EPA’s
guide: Flood Resilience: A Basic Guide for Water and
Wastewater Utilities 20 and EPA’s website 21 Creating Resilient
Water Utilities (CRWU) helpful for completing this component.
The Asset Vulnerability Evaluation shall include, at a minimum, the
following:
(a) Description of planning priorities related to the location of the
sewer system;
(b) Identification of all assets (e.g., pump stations, pipes, etc.), the
elevation of the asset, and if the asset falls into the 100-year flood
map or the 500-year flood map, 22
(c) Description of structural improvements, and/or other mitigation
measures 23 to minimize 24 the impacts of major storm and flood
events to each specific asset identified in Part I.E.2.e.(2).i.(b)
above.
The Permittee, CSO-responsible Co-Permittees, and Co-permittees
shall consider, at a minimum, the following measures:
(i) Construction of flood barriers to protect structure or
reinforce existing structures to withstand flooding and
additional exertion of force;
(ii) Establish remote locations for operations, equipment,
records and data backups;
(iii) Plan and establish alternative or on-site power supply; 25
20 https://www.epa.gov/sites/default/files/2015-08/documents/flood_resilience_guide.pdf
21 https://www.epa.gov/crwu
22 See https://www.epa.gov/sites/default/files/2015-08/documents/flood_resilience_guide.pdf for a basic guide to
flood resiliency for water and wastewater utilities.
23 Mitigation measure can be an emergency planning activity, equipment modification/upgrade or new capital
investment/construction project.
24 For the purposes of this provision, the term “minimize” means to reduce and/or eliminate to the extent achievable
the impacts to the facilities.
25 The Permittee shall clearly document measures taken specifically to manage energy system disruptions, such as a
general power outage, well as document whether and, if so, to what extent, power supply adequate to ensure safe
and reliable operations of the facility is threatened during a major storm or flood. They shall clearly document
measures that have been taken to address any risks the facility faces of losing power during a major storm or flood in
a manner that could result in environmental or public health impacts.
NPDES Permit No. MA0103284 2023 Draft Permit
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(iv) Relocate facilities and/or infrastructure to higher elevations;
(v) Catalog emergency resources used during a major storm or
flood event;
(vi) Develop emergency response plans;
(vii) Establish mutual aid agreements with neighboring utilities;
(viii) Integrate long-term risks into capital improvement plans;
(ix) Participate in community planning and regional
collaborations;
(x) Conduct staff training for implementing your emergency
procedures at regular intervals;
(xi) When designing new or replacement facilities, strive to
locate facilities above the base flood elevation; 26
(xii) Identify the source of data used to assess vulnerabilities to
major storm and flood events; and
(xiii) Identify the potential funding sources 27 for resilience
planning and implementation (e.g., EPA, FEMA, MassDEP,
capital planning, etc.).
ii. Component 2: Systemic Vulnerability Evaluation. Upon
completing assessment of the vulnerabilities of individual
assets, the Permittee and Co-permittee shall evaluate the
vulnerability of its sewer system as a whole. This second
component of the plan shall include, at a minimum. a
systematic vulnerability evaluation for each asset identified in
Part I.E.2.e.(2).i.(b), including the following:
(a) Define the criticality of each asset to the overall sewer system
operations; and
(b) Identify the highest priority assets for the sewer system and
measures 28 taken to reduce system vulnerability to risks that
could degrade the overall system operations in a manner that
would result in environmental or public health impacts.
26 For MA facilities, for activities proposed within Areas Subject to Protection under M.G.L. c. 131, § 40 or the 100-
foot buffer zone, the Base Flood Elevation is defined at 310 CMR 10.04, Definitions of Special Flood Hazard Area,
Velocity Zone, and Coastal High Hazard Area, Land Subject to Coastal Storm Flowage at 310 CMR 10.36 and
Bordering Land Subject to Flooding, and Isolated Land Subject to Flooding at 310 CMR 10.57. Also refer to the
Massachusetts State Building Code for any other required standards related to Base Flood Elevation.
27 See https://www.epa.gov/fedfunds
28 For example, an asset like a pumping station or headworks is often ranked “high” for criticality, as the safe and
reliable operation of many assets during a major storm or flood depend upon the continued operation of that
particular asset. If a pump station is degraded or fails, the operations of many other assets can degrade or fail,
resulting in environmental or public health impacts.
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iii. Component 3: Alternatives Evaluation . Upon completing
assessment of the vulnerabilities of the sewer system as a
whole, the Permittee, CSO-responsible Co-Permittees, and Co-
permittees shall provide an assessment of individual asset-
specific, and/or, if appropriate, combinations of mitigation
measures must be presented in order to determine the most
effective mitigation measures to minimize the impact of major
storm and flood events.
This third component shall include, at a minimum, the following with regard to
alternative evaluation, at a minimum:
(a) An evaluation of alternatives including a cost-effectiveness
analysis and a review of technical, environmental, and
institutional factors. The alternatives analysis should conclude
with the development of a recommended plan.
(b) For each alternative, quantitatively document (including
assumptions and methodologies) the residual risk today and
for the midterm (i.e., 20-30 years) and long-term (i.e., 80-100
years). The evaluation should include estimates of which
customers and geographic areas bear the residual risk from the
approach to resiliency planning in that system. Residual risk is
a term that refers to the risk remaining for an asset or system,
after mitigation measures are taken.
(c) For each asset, document the total projected alternatives for
implementing all planned mitigation measures identified in
the Sewer System Major Storm and Flood Events Plan.
(d) Selection of mitigation measures to be undertaken, including:
(i) a schedule to implement each selected mitigation measure;
and
(ii) a map showing the location of planned mitigation
measures.
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iv. Annual Report. The Permittee and Co-permittee shall submit
an Annual Operation and Maintenance Report on the Sewer
System Major Storm and Flood Events Plan implementation
and results for the prior calendar year including documenting
any changes to the sewer system or other assets that may
impact the current vulnerability evaluation. The first annual
report is due the first March 31 following submittal of the
Sewer System Major Storm and Flood Events Plan and shall be
included with the annual report required in Part I.E.3 below.
(3) The full Sewer System O&M Plan shall be completed, implemented, and
submitted to EPA and to MassDEP within twenty-four (24) months from
the effective date of this Permit. The Plan shall include:
i. The required submittal from paragraph I.E.2.e.(1) above,
updated to reflect current information;
ii. A preventive maintenance and monitoring program for the
collection system; including resiliency evaluation and planning
that the Permittee, CSO-responsible Co-permittees and Co-
permittees owns and operates;
iii. Description of sufficient staffing necessary to properly operate
and maintain the sanitary sewer collection system that the
Permittee, CSO-responsible Co-permittees, and Co-permittees
owns and operates and how the operation and maintenance
program is staffed;
iv. Description of funding, the source(s) of funding and provisions
for funding sufficient for implementing the plan that the
Permittee, CSO-responsible Co-permittees, and Co-permittees
owns and operates plan;
v. Identification of known and suspected overflows and back-ups,
including manholes. A description of the cause of the identified
overflows and back-ups, corrective actions taken, and a plan
for addressing the overflows and back-ups consistent with the
requirements of this permit that apply to the Permittee, CSO-
responsible Co-permittees, and Co-permittees;
vi. A description of the Permittee’s, CSO-responsible Co-
permittee’s, or Co-permittee's programs for preventing I/I
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related effluent violations and all unauthorized discharges of
wastewater, including overflows and by-passes and the
ongoing program to identify and remove sources of I/I. The
program shall include an inflow identification and control
program that focuses on the disconnection and redirection of
illegal sump pumps and roof down spouts;
vii. An educational public outreach program for all aspects of I/I
control, particularly private inflow; and
viii. An Overflow Emergency Response Plan to protect public
health from overflows and unanticipated bypasses or upsets
that exceed any effluent limitation in the Permit.
ix. The resiliency evaluation and planning portion of the Sewer
System O&M Plan shall be revised at least every five years.
See Part I.E.2.e.(2).
3. Annual Reporting Requirement
The Permittee, CSO-responsible Co-permittees and Co-permittees shall submit a
summary report of activities related to the implementation of its O&M Plan during the
previous calendar year. The report shall be submitted to EPA and to MassDEP annually
by March 31. The first annual report is due on the first March 31 following submittal of
the O&M Plan required by Part I.E. of this Permit. The summary report shall, at a
minimum, include:
a. A description of the staffing levels maintained during the year;
b. A map and a description of inspection and maintenance activities conducted, and
corrective actions taken during the previous year;
c. Expenditures for any collection system maintenance activities and corrective
actions taken during the previous year;
d. A map with areas identified for investigation/action in the coming year;
e. A summary of unauthorized discharges during the past year and their causes and a
report of any corrective actions taken as a result of the unauthorized discharges
reported pursuant to the Unauthorized Discharges section of this Permit; and
f. If the average annual flow in the previous calendar year exceeded 80 percent of the
facility's 361 MGD design flow (288.8 MGD), or there have been capacity related
overflows, the report shall include:
(4) Plans for further potential flow increases describing how the Permittee
will maintain compliance with the flow limit and all other effluent
limitations and conditions; and
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(5) A calculation of the maximum daily, weekly, and monthly infiltration and
the maximum daily, weekly, and monthly inflow for the reporting year.
g. The Annual Operation and Maintenance Report on the implementation and results
of the WWTF Major Storm and Flood Events Plan (beginning the first March 31
following submittal of this Plan) for the prior calendar year; and
h. The Annual Operation and Maintenance Report on the implementation and results
of the Sewer System Major Storm and Flood Events Plan (beginning the first
March 31 following submittal of this Plan) for the prior calendar year.
F. ALTERNATE POWER SOURCE
In order to maintain compliance with the terms and conditions of this Permit, the Permittee,
CSO-responsible Co-permittees and Co-permittees shall provide an alternative power source(s)
sufficient to operate the portion of the publicly owned treatment works it owns and operates, as
defined in Part II.E.1 of this Permit.
G. INDUSTRIAL USERS AND PRETREATMENT PROGRAM
1. The Permittee shall submit to EPA and the State the name of any Industrial User (IU) subject
to Categorical Pretreatment Standards under 40 CFR § 403.6 and 40 CFR chapter I,
subchapter N (Parts 405-415, 417-430, 432, 447, 449-451, 454, 455, 457-461, 463-469, and
471 as amended) who commences discharge to the facility after the effective date of this
permit.
This reporting requirement also applies to any other IU who is classified as a Significant
Industrial User (SIU) which discharges an average of 25,000 gallons per day or more of
process wastewater into the facility (excluding sanitary, noncontact cooling and boiler
blowdown wastewater); contributes a process wastewater which makes up five (5) percent or
more of the average dry weather hydraulic or organic capacity of the facility; or is designated
as such by the Control Authority as defined in 40 CFR § 403.3(f) on the basis that the
industrial user has a reasonable potential to adversely affect the wastewater treatment
facility’s operation, or for violating any pretreatment standard or requirement (in accordance
with 40 CFR § 403.8(f)(6)).
2. In the event that the Permittee receives originals of reports (baseline monitoring reports, 90-
day compliance reports, periodic reports on continued compliance, etc.) from industrial users
subject to Categorical Pretreatment Standards under 40 CFR § 403.6 and 40 CFR chapter I,
subchapter N (Parts 405-415, 417-430, 432-447, 449-451, 454, 455, 457-461, 463-469, and
471 as amended), or from a Significant Industrial User, the Permittee shall forward the
originals of these reports within ninety (90) days of their receipt to EPA, and copy the State.
3. In accordance with 40 CFR § 122.44(j)(1) the Permittee must identify, in terms of character
and volume, any SIUs discharging into the POTW or facility subject to Pretreatment
Standards under section 307(b) of CWA and 40 CFR Part 403. SIUs information shall be
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updated at a minimum of once per year or at that frequency necessary to ensure that all SIUs
are properly permitted and/or controlled. The records shall be maintained and updated as
necessary.
4. Beginning the first full calendar year after the effective date of the Permit, the Permittee shall
commence annual sampling of the following types of industrial discharges into the POTW:
• Commercial Car Washes
• Platers/Metal Finishers
• Paper and Packaging Manufacturers
• Tanneries and Leather/Fabric/Carpet Treaters
• Manufacturers of Parts with Polytetrafluoroethylene (PTFE) or teflon type
coatings (i.e., bearings)
• Landfill Leachate
• Centralized Waste Treaters
• Known or Suspected PFAS Contaminated Sites
• Fire Fighting Training Facilities
• Airports
• Any Other Known or Expected Sources of PFAS
Sampling shall be conducted using Method 1633 for the PFAS analytes listed in Attachment
H . The industrial discharges sampled, and the sampling results shall be summarized and
submitted to EPA and copy the State as an electronic attachment to the March discharge
monitoring report due April 15 of the calendar year following the testing.
5. Legal Authority
The Permittee has been delegated primary responsibility for enforcing against discharges
prohibited by 40 CFR § 403.5 and applying and enforcing any national Pretreatment
Standards established by the United States Environmental Protection Agency in
accordance with Section 307 (b) and (c) of The Clean Water Act (Act), as amended by
The Water Quality Act (WQA), of 1987.
The Permittee shall operate an industrial pretreatment program in accordance with the
General Pretreatment Regulations found in 40 CFR Part 403 and the approved
pretreatment program submitted by the Permittee. The pretreatment program was
approved on July 20, 1982 and has subsequently incorporated substantial modifications
as approved by EPA. The approved pretreatment program, and any approved
modifications thereto, is hereby incorporated by reference and shall be implemented in a
manner consistent with the following procedures, as required by 40 CFR Part 403.
The Permittee must have or develop a legally enforceable municipal code or rules and
regulations to authorize or enable the POTW to apply and enforce the requirements of
Sections 307(b) and (c) and 402(b)(8) and (9) of the Act and comply with the
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requirements of § 403.8(f)(1). At a minimum, this legal authority shall enable the POTW
to:
a. Deny or condition new or increased contributions of pollutants, or changes in the
nature of pollutants, to the POTW by Industrial Users where such contributions do
not meet applicable Pretreatment Standards and Requirements or where such
contributions would cause the POTW to violate its NPDES Permit;
b. Require compliance with applicable Pretreatment Standards and Requirements by
Industrial Users;
c. Control through permit, order, or similar means, the contribution to the POTW by
each Industrial User to ensure compliance with applicable Pretreatment Standards
and Requirements. In the case of Industrial Users this control shall be achieved
through permits or equivalent control mechanism identified as significant under 40
CFR § 403.3(v), as required by § 403.8(f)(1)(iii);
d. Require (a) the development of a compliance schedule by each Industrial User for
the installation of technology required to meet applicable Pretreatment Standards
and Requirements and (b) the submission of all notices and self-monitoring reports
from Industrial Users as are necessary to assess and assure compliance by
Industrial Users with Pretreatment Standards and Requirements, including but not
limited to the reports required in § 403.12;
e. Carry out all inspection, surveillance and monitoring procedures necessary to
determine, independent of information supplied by Industrial Users, compliance or
noncompliance with applicable Pretreatment Standards and Requirements by
Industrial Users. At a minimum, all significant industrial users shall be sampled
and inspected at the frequency established in the approved IPP, but in no case less
than once per year, and with adequate maintenance of records, Representatives of
the POTW shall be authorized to enter any premises of any Industrial User in
which a Discharge source or treatment system is located or in which records are
required to be kept under § 403.12(o) to assure compliance with Pretreatment
Standards. Such authority shall be at least as extensive as the authority provided
under section 308 of the Act;
f. Obtain remedies for noncompliance by any Industrial User with any Pretreatment
Standard and Requirement. All POTW's shall be able to seek injunctive relief for
noncompliance by Industrial Users with Pretreatment Standards and Requirements.
All POTWs shall also have authority to seek or assess civil or criminal penalties in
at least the amount of $1,000 a day for each violation by Industrial Users of
Pretreatment Standards and Requirements in accordance with §
403.8(f)(1)(vii)(A); and
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g. Comply with the confidentiality requirements set forth in § 403.14.
6. Implementation Requirements
The Permittee shall operate a pretreatment program in accordance with the General
Pretreatment Regulations found in 40 CFR Part 403 and with the legal authorities,
policies, procedures, and financial provisions of the approved Pretreatment program
submitted by the Permittee. The approved Pretreatment program, and any approved
modifications thereto, is hereby incorporated by reference and shall be implemented in a
manner consistent with the following procedures, as required by 40 CFR Part 403:
a. In accordance with 40 CFR § 122.44(j)(1), Identify, in terms of character and
volume of pollutants contributed from Industrial Users discharging into the POTW
subject to Pretreatment Standards under section 307(b) of CWA and 40 CFR Part
403.
b. The Permittee must notify these identified Industrial Users of applicable
Pretreatment Standards and any applicable requirements in accordance with 40
CFR § 403.8(f)(2)(iii). Pursuant to 40 CFR § 403.8(f)(6), prepare and maintain a
list of significant industrial users and identify the criteria in 40 CFR § 403.3(v)(1)
applicable to each industrial user.
c. The Permittee must carry out inspection procedures and randomly sample and
analyze the effluent from Industrial Users and conduct surveillance activities in
accordance with 40 CFR § 403.8(f)(2)(v), which will determine independent of
information supplied by the industrial user, whether the industrial user is in
compliance with the Pretreatment Standards. At a minimum, all significant
industrial users shall be sampled and inspected at the frequency established in the
approved IPP but in no case less than once per year and maintain adequate records.
d. The Permittee shall receive and analyze self-monitoring reports and other notices
submitted by Industrial Users in accordance with the self-monitoring requirements
in 40 CFR § 403.12; This must include timely and appropriate reviews of
industrial user reports and notifications to identify all violations of the user's
permit, the local ordinance, and federal pretreatment standards and requirements.
e. The Permittee shall evaluate whether each SIU needs a plan to control Slug
Discharges in accordance with 40 CFR § 403.8(f)(2)(vi). SIUs must be evaluated
within 1 year of being designated an SIU. If required, the Permittee shall require
the SIU to prepare or update and implement a slug prevention plan that contains at
least the minimum required elements in 40 CFR § 403.8(f)(2)(vi)(A-D) and
incorporate the slug control requirements into the SIU’s control mechanism.
f. Pursuant to 40 CFR § 403.8(f)(2)(vii), the Permittee shall investigate instances of
non-compliance with Pretreatment Standards and requirements indicated in
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required reports and notices or indicated by analysis, inspection, and surveillance
activities.
g. The Permittee shall publish, at least annually, in a newspaper or newspapers of
general circulation that provides meaningful public notice within the jurisdiction(s)
served by the POTW, a list of all non-domestic users which, at any time in the
previous 12 months, were in significant noncompliance as defined in 40 CFR §
403.8 (f)(2)(viii).
h. The Permittee shall provide sufficient resources and qualified personnel to
implement its Pretreatment program in accordance with 40 CFR § 403.8(f)(3);
i. The Permittee shall enforce all applicable Pretreatment Standards and requirements
and obtain remedies for noncompliance by any industrial user. The Permittee shall
develop, implement, and maintain an enforcement response plan in accordance
with 40 CFR § 403.8(f)(5).
j. Pursuant to 40 CFR § 403.8(g), the Permittee that chooses to receive electronic
documents must satisfy the requirements of 40 CFR Part 3 – (Electronic reporting).
7. Local Limit Development
a. The Permittee shall develop, continually maintain, and enforce, as necessary, local
limits to implement the general and specific prohibitions in 40 CFR § 403.5(c)(1)
which prohibit the introduction of any pollutant(s) which cause pass through or
interference and the introduction of specific pollutants to the waste treatment
system from any source of non-domestic discharge.
b. The Permittee shall develop and enforce specific effluent limits (local limits) for
Industrial User(s), and all other users, as appropriate, which together with
appropriate changes in the POTW Treatment Plant's Facilities or operation, are
necessary to ensure continued compliance with the POTW's NPDES permit or
sludge use or disposal practices. Specific local limits shall not be developed and
enforced without individual notice to persons or groups who have requested such
notice and an opportunity to respond. Within 90 days of the effective date of the
Permit, the Permittee shall prepare and submit a written technical evaluation to
EPA analyzing the need to revise local limits. As part of this evaluation, the
Permittee shall assess how the POTW performs with respect to influent and
effluent of pollutants, water quality concerns, sludge quality, sludge processing
concerns/inhibition, biomonitoring results, activated sludge inhibition, worker
health and safety and collection system concerns. In preparing this evaluation, the
Permittee shall complete and submit the attached form (see Attachment F
(Reassessment of Technically Based Industrial Discharge Limits)) with the
technical evaluation to assist in determining whether existing local limits need to
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be revised. Justifications and conclusions should be based on actual plant data if
available and should be included in the report. Should the evaluation reveal the
need to revise local limits, the Permittee shall complete the revisions within 120
days of notification by EPA and submit the revisions to EPA for approval. The
Permittee shall carry out the local limits revisions in accordance with EPA’s Local
Limit Development Guidance (July 2004).
8. Notification Requirements
a. The Permittee must notify EPA of any new introductions or any substantial change
in pollutants from any Industrial User within sixty (60) days following the
introduction or change, as required in 40 § CFR 122.42(b)(1-3). Such notice must
identify:
(1) Any new introduction of pollutants from an Industrial User which would
be subject to Sections 301, 306, and 307 of the Act if it were directly
discharging those pollutants; or
(2) Any substantial change in the volume or character of pollutants being
discharged by any Industrial User;
(3) For the purposes of this section, adequate notice shall include information
on:
i. The identity of the Industrial User;
ii. The nature and concentration of pollutants in the discharge and
the average and maximum flow of the discharge; and
iii. Any anticipated impact of the change on the quantity or quality
of effluent to be discharged from or biosolids produced at such
POTW.
b. The Permittee must notify EPA as soon as possible of any planned physical
alterations or additions to the permitted facility. Notice is required when:
(1) The alteration or addition to a permitted facility may meet one of the
criteria for determining whether a facility is a new source pursuant to 40
CFR § 122.29 (b);
(2) The alteration or addition could significantly change the nature or increase
the quantity of pollutants discharged; or
(3) The alteration or addition results in a significant change in the Permittee's
sludge use or disposal practices.
c. The Permittee must notify EPA if the POTW modifies or intends to modify its
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Pretreatment Program.
d. The Permittee must notify EPA of any instance of pass through or interference,
known or suspected to be related to a discharge from an Industrial User. The
notification shall be attached to the DMR submitted EPA and shall describe the
incident, including the date, time, length, cause, and the steps taken by the
Permittee and Industrial User to address the incident.
e. The Permittee shall notify all Industrial Users of the users’ obligations to comply
with applicable requirements under Subtitles C and D of the Resource
Conservation and Recovery Act (RCRA) and that Industrial Users shall certify that
it has a program in place to reduce the volume and toxicity of hazardous wastes
generated to the degree it has determined to be economically practical as well as
their obligation to notify the EPA Regional Waste Management Division Director,
in writing, of any discharge into the POTW of a substance, which, if otherwise
disposed of, would be a hazardous waste under 40 CFR Part 261. Such notification
must include:
(1) the name of the hazardous waste as set forth in 40 CFR Part 261;
(2) the EPA hazardous waste number; and
(3) the type of discharge (continuous, batch, or other).
9. Annual Report Requirements
The Permittee shall provide EPA with a hard copy annual report that briefly describes the
POTW's program activities, including activities of all participating agencies, if more than one
jurisdiction is involved in the local program. The report required by this section shall be
submitted no later than one year after approval of the POTW's Pretreatment Program, and at
least annually thereafter. The report must include, at a minimum, the applicable required data
in Appendix A to 40 CFR Part 127, a summary of changes to the POTW's pretreatment
program that have not been previously reported to EPA, and any other relevant information
requested by EPA. Beginning on December 21, 2025, all annual reports submitted in
compliance with this section must be submitted electronically by the POTW Pretreatment
Program to EPA or initial recipient, as defined in 40 CFR § 127.2(b). Electronic submittals
shall be in compliance with this section and 40 CFR Part 3 (including, in all cases, subpart D
to Part 3), 40 CFR § 122.22(e), and 40 CFR Part 127 (Part 127 is not intended to undo
existing requirements for electronic reporting). Prior to this date, and independent of 40 CFR
Part 127, EPA may also require POTW Pretreatment Programs to electronically submit
annual reports under this section if specified by a particular permit or if required to do so by
state law.
The Permittee shall provide EPA with an annual report describing the Permittee's
pretreatment program activities for the twelve (12) month period ending 60 days prior to the
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due date in accordance with 40 CFR § 403.12(i). The annual report shall be consistent with
the format described in Attachment G (NPDES Permit Requirement for Industrial
Pretreatment Annual Report) of this Permit and shall be submitted by March 31st of each
year.
10. Beginning the first full calendar year after the effective date of the Permit, the Permittee shall
commence annual sampling of the following types of industrial discharges into the POTW:
• Commercial Car Washes
• Platers/Metal Finishers
• Paper and Packaging Manufacturers
• Tanneries and Leather/Fabric/Carpet Treaters
• Manufacturers of Parts with Polytetrafluoroethylene (PTFE) or teflon type
coatings ( e.g. , bearings)
• Landfill Leachate
• Centralized Waste Treaters
• Known or Suspected PFAS Contaminated Sites
• Fire Fighting Training Facilities
• Airports
• Any Other Known or Expected Sources of PFAS
Sampling shall be conducted using Method 1633 for the PFAS analytes listed in Attachment
H. The industrial discharges sampled, and the sampling results shall be summarized and
included in the annual report (see Part I.G.9).
H. SLUDGE CONDITIONS
1. The Permittee shall comply with all existing federal and state laws and regulations that apply
to sewage sludge use and disposal practices, including EPA regulations promulgated at 40
CFR § 503, which prescribe “Standards for the Use or Disposal of Sewage Sludge” pursuant
to § 405(d) of the CWA, 33 U.S.C. § 1345(d).
2. If both state and federal requirements apply to the Permittee’s sludge use and/or disposal
practices, the Permittee shall comply with the more stringent of the applicable requirements.
3. The requirements and technical standards of 40 CFR Part 503 apply to the following sludge
use or disposal practices:
a. Land application - the use of sewage sludge to condition or fertilize the soil;
b. Surface disposal – the placement of sewage sludge in a sludge only landfill; and
c. Sewage sludge incineration in a sludge only incinerator.
4. The requirements of 40 CFR Part 503 do not apply to facilities which dispose of sludge in a
municipal solid waste landfill. 40 CFR § 503.4. These requirements also do not apply to
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facilities which do not use or dispose of sewage sludge during the life of the permit but rather
treat the sludge (e.g., lagoons, reed beds), or are otherwise excluded under 40 CFR § 503.6.
5. The 40 CFR Part 503 requirements include the following elements:
a. General requirements
b. Pollutant limitations
c. Operational Standards (pathogen reduction requirements and vector attraction
reduction requirements)
d. Management practices
e. Record keeping
f. Monitoring
g. Reporting
Which of the 40 CFR Part 503 requirements apply to the Permittee will depend upon
the use or disposal practice followed and upon the quality of material produced by a
facility. The EPA Region 1 guidance document, “EPA Region 1 - NPDES Permit
Sludge Compliance Guidance” (November 4, 1999), may be used by the Permittee to
assist it in determining the applicable requirements.
6. The sludge shall be monitored for pollutant concentrations (all Part 503 methods) and
pathogen reduction and vector attraction reduction (land application and surface disposal) at
the following frequency. This frequency is based upon the volume of sewage sludge
generated at the facility in dry metric tons per year, as follows:
less than 290 1/ year
290 to less than 1,500 1 /quarter
1,500 to less than 15,000 6 /year
15,000 + 1 /month
Sampling of the sewage sludge shall use the procedures detailed in 40 CFR § 503.8.
7. Under 40 CFR § 503.9(r), the Permittee is a “person who prepares sewage sludge” because it
“is … the person who generates sewage sludge during the treatment of domestic sewage in a
treatment works ….” If the Permittee contracts with another “person who prepares sewage
sludge” under 40 CFR § 503.9(r) – i.e., with “a person who derives a material from sewage
sludge” – for use or disposal of the sludge, then compliance with Part 503 requirements is the
responsibility of the contractor engaged for that purpose. If the Permittee does not engage a
“person who prepares sewage sludge,” as defined in 40 CFR § 503.9(r), for use or disposal,
then the Permittee remains responsible to ensure that the applicable requirements in Part 503
are met. 40 CFR § 503.7. If the ultimate use or disposal method is land application, the
Permittee is responsible for providing the person receiving the sludge with notice and
necessary information to comply with the requirements of 40 CFR § 503 Subpart B.
8. The Permittee shall submit an annual report containing the information specified in the 40
CFR Part 503 requirements (§ 503.18 (land application), § 503.28 (surface disposal), or
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§ 503.48 (incineration)) by February 19 (see also “EPA Region 1 - NPDES Permit Sludge
Compliance Guidance”). Reports shall be submitted electronically using EPA’s Electronic
Reporting tool (“NeT”) (see “Reporting Requirements” section below).
I. SPECIAL CONDITIONS
1. Best Management Practices (BMP) Plan
The Permittee, MWRA, shall continue to implement the BMP Plan that was developed as
a requirement of the 2000 Permit and approved by EPA and MassDEP. The Plan shall
continue to reflect activities at Deer Island, all headworks facilities, all CSO Treatment
Facilities, and the sludge pelletizing plant at Fore River. The Permittee shall maintain a
copy of the current Plan at DITP.
Any change in the facility which materially increases the potential for the ancillary
activities to result in a release of hazardous or toxic pollutants, the Permittee shall update
the BMP Plan. Changes to the BMP Plan shall be submitted to EPA.
2. Pollution Prevention Plan
a. The Permittee, MWRA, shall update and continue to make available their
Household Hazardous Waste booklet in both hard copy and on-line formats. The
updates should include information on the sources and proper disposal of
Pharmaceuticals and Personal Care Products (PPCPs), PFAS, and microplastics.
MWRA shall make this information available on their website and in hard copy,
upon request, to all the sewer member communities.
b. The Permittee, MWRA, shall continue to administer the school curriculum that
covers the wastewater treatment process and the importance of individuals keeping
the harbor clean by not polluting. The curriculum should be updated to include
contaminants of emerging concern (CEC) including PFASs, PPCPs and
microplastics.
c. The Permittee, MWRA, shall continue to provide outreach to schools and
community groups concerning the Boston Harbor Cleanup and how they can
practice pollution prevention at home through reducing their use of hazardous
household products and the proper disposal of HHW and CEC.
3. Best Management Practices for Outfall
The Permittee, MWRA, shall operate Outfall T01 according to the best management practices
below:
a. The outfall shall be maintained to ensure proper operation. Proper operation means
that the outfall pipe be intact, operating as designed, and have unobstructed flow.
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Maintenance may include dredging in the vicinity of the outfall, removal of
solids/debris in the outfall header pipe, and repair/replacement.
b. To determine if maintenance will be required, the Permittee, MWRA, shall inspect
and videotape the operation of the outfall either remotely or using a qualified diver
or marine contractor. At a minimum, the inspections and videotaping shall be
performed once every five years with the first inspection occurring within twelve
(12) months of the effective date of the permit. EPA and MassDEP shall be
contacted at least seven days prior to a dive inspection.
c. Any necessary maintenance dredging must be performed only during the marine
construction season authorized by the Massachusetts Department of Marine
Fisheries and only after receiving all necessary permits from the Massachusetts
Department of Environmental Protection, U.S. Coast Guard, U.S. Army Corps of
Engineers, and other appropriate agencies.
d. Copies of reports summarizing the results of each outfall inspection shall be
submit to EPA and MassDEP within 60 days of each inspection. Where it is
determined that maintenance will be necessary, the Permittee shall provide the
proposed schedule for the maintenance.
e. Attached to its monthly DMR report, the Permittee shall submit a monthly report
to EPA that includes (1) ongoing performance of the diffusers as determined by the
flow versus hydraulic head relationship, (2) number of risers and ports opened and
closed, and (3) information available from any video inspections collected that
month.
4. The Permittee, CSO-responsible Co-permittees and Co-permittees shall notify the
Massachusetts Division of Marine Fisheries within 4 hours of becoming aware of any
emergency condition, plant upset, bypass, SSO discharges or other system failure of the
portion of the POTW that they own and operate which has the potential to violate bacteria
permit limits and within 24 hours of becoming aware of a permit excursion or plant failure.
The notification shall be sent to the following address and telephone number:
Division of Marine Fisheries
Shellfish Management Program
30 Emerson Avenue
Gloucester, MA 01930
(978) 282-0308
5. Pursuant to 40 § CFR 125.123(d)(4), this Permit shall be modified or revoked at any time if,
on the basis of any new data, the Director determines that continued discharges may cause
unreasonable degradation of the marine environment.
6. Ambient Monitoring Plan
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Within 30 days of the effective date of the Permit, the Permittee shall submit a revised
Ambient Monitoring Plan to EPA and MassDEP. The Permittee will continue to monitor
as required in the 2021 Ambient Monitoring Plan, Revision 2.1 29 until the revised
Ambient Monitoring Plan is approved. The plan must comply with applicable local, state
and federal regulations and shall consist of the following elements, at a minimum:
a. The Permittee may use elements of Ambient Monitoring Plan, Revision 2.1 as the
basis for the revised Plan but focused on Water Column Monitoring requirements
outlined below.
b. The Permittee shall also prepare a Quality Assurance Project Plan for the approved
Ambient Monitoring Plan for State review and approval.
c. Survey Dates
Unless otherwise specified, surveys shall be conducted 9 times per year according to the
following table:
Table 1: Water Column Survey Schedule from Ambient Monitoring Plan, Revision 2.1.
When Target
Week
Original
Survey
Number
Purpose
Early February 6 1 Nutrient conditions near the start of the
spring bloom
March 12 3 Spring bloom
Early April 15 4 Capture Phaeocystis bloom. Later
winter/spring bloom nutrients
Mid-May 20 6 Nutrient/water column conditions at the
end of winter/spring, Alexandrium
Mid-June 25 7 Early summer stratification and
nutrients. Mid-late Alexandrium season
Mid-July 30 9 Mid-summer stratification and
nutrients
Mid-August 34 11 Mid-summer stratification and
nutrients
September 36 12 Nutrients, etc. prior to overturn.
Late October 43 14 Mid-fall bloom nutrients, DO minima,
etc.
d. Monitoring Stations
29 https://www3.epa.gov/region1/npdes/mwra/omsap/pdfs/mwra-amp-rev-2-1-report-2021-08.pdf
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The Plan shall include the existing eleven (11) monitoring stations in Massachusetts Bay:
F22, N04, N01, N21, N18, N07, F23, F15, F13, F10, and F06 and the existing three (3)
monitoring stations in Cape Cod Bay: F29, F02 and F01. (See Ambient Monitoring Plan,
Revision 2.1, Tables 3-2 and 3-3.)
e. Monitoring Parameters
The plan shall include the parameters shown below in Tables 2 & 3 (new requirements
are in bold). Additional information can be found in MWRA’s Quality Assurance Project
Plan (QAPP) for Water Column Monitoring 2020-2022, Tasks 4, 5, 6, 7 10. 30
Table 2: Water Column Parameters in Massachusetts Bay
ANALYTE DEPTH PARAMETER
Hydro profile Downcast data continuous,
with upcast data at any
sampled depth
Temperature
pH
Salinity
Dissolved Oxygen
Chlorophyll fluorescence
Turbidity
Transmissometry
PAR/ Irradiance
Depth of sensors
Water Chemistry Five depths. Surface,
bottom, and three
intermediate depths which
includes the chlorophyll
maximum
Ammonium
Nitrate
Nitrite
Total dissolved nitrogen
Particulate nitrogen
Phosphate
Total dissolved phosphorus
Particulate phosphorus
Silicate
Particulate carbon
Alexandrium catenella Two depths Gene probe
Phytoplankton
Zooplankton
Near surface
Net Tow for Zooplankton
Plankton will not be
measured at station N21
because nearfield plankton
is adequately characterized
by data collected at the
Identification
Enumeration
30 Libby PS, Whiffen-Mansfield AD, Nichols KB, Lescarbeau GR, Borkman DG, Turner JT, 2021, Quality
Assurance Project Plan (QAPP) for water column monitoring 2020-2022: Tasks 4-7 and 10, Revision 1. Boston,
Massachusetts Water Resources Authority. Report 2021-01. 66p. https://www.mwra.com/harbor/enquad/pdf/2021-
01.pdf
NPDES Permit No. MA0103284 2023 Draft Permit
Page 58 of 68
ANALYTE DEPTH PARAMETER
other four nearfield
stations
Table 3: Water Column Parameters in Cape Cod Bay and Stellwagen NMS
ANALYTE DEPTH PARAMETER
Hydro profile Downcast data continuous,
with upcast data at any
sampled depth
Temperature
pH
Salinity
Dissolved Oxygen
Chlorophyll fluorescence
Transmissometry
PAR/ Irradiance
Depth of sensors
Water Chemistry Two depths
Near surface and near
bottom
Ammonium
Nitrate + nitrite
Phosphate
Total Nitrogen
Total Phosphorus
Extracted chlorophyll
Alexandrium catenella Two depths Gene probe
Phytoplankton
Zooplankton
Near surface
Net tow
Identification
Enumeration
f. Harmful algal blooms and nuisance algae
Identify and enumerate the following algal taxa: Alexandrium catenella, Pseudo-nitzschia
spp., Dinophysis spp., Phaeocystis pouchetii, Karenia mikimotoi, and Margalefidinium
polykrikoides as required in above in Tables 2 and 3.
(1) Alexandrium catenella
Alexandrium catenella shall continue to be enumerated using the gene probe method
identified in the AMP, Revision 2.1., page 42 and the QAPP, Table B-4. MWRA shall
conduct Alexandrium Rapid Response Study (ARRS) following the current Alexandrium
Rapid Response Study Survey Plan, Revision 1 31 and based on the following one or more
of the following scenarios occurring:
31 Libby PS, Rex AC, Keay KE, Mickelson MJ. 2013. Alexandrium Rapid Response Study Survey Plan. Revision 1.
Boston: Massachusetts Water Resources Authority. Report 2013-06. 13 p.
https://www.mwra.com/harbor/enquad/pdf/2013-06.pdf
NPDES Permit No. MA0103284 2023 Draft Permit
Page 59 of 68
i. MWRA shall begin weekly surveys for Alexandrium when
information suggests that:
(a) A bloom is present in Massachusetts Bay or imminent.
(b) If Alexandrium values exceed 100 cells/L.
(c) If high levels of paralytic shellfish poisoning (PSP) toxicity
in blue mussels are reported as defined below:
a. If PSP toxicity in blue mussels at Cohasset, Scituate
or Marshfield (MA DMF stations) exceeds 40 μg
toxin per 100 g shellfish meat, MWRA will conduct
a weekly ARRS survey.
Or
If PSP toxicity in blue mussels exceeds 40 μg at
stations between Gloucester, MA and Cape
Elizabeth, ME, assume that there is a bloom in the
Gulf of Maine. MWRA will evaluate the likelihood
that wind and currents will bring the bloom into
Massachusetts Bay and staff will use professional
judgement to decide whether to begin the weekly
ARRS surveys.
(d) MWRA shall monitor data on PSP toxicity results from the
following sources:
Maine Department of Marine Resources (ME-DMR)
https://www.maine.gov/dmr/fisheries/shellfish/closures
New Hampshire Fish and Game
https://www.wildlife.state.nh.us/marine/redtide.html
Massachusetts Division of Marine Fisheries (MA-DMF)
https://www.mass.gov/lists/biotoxin-notices#2023-
notices-
Northeast PSP Listserver
http://mailman.whoi.edu/mailman/listinfo/northeastpsp
(e) Once MWRA begins an ARRS survey, it will continue
weekly sampling for Alexandrium until the measured
Alexandrium abundance decreases below 100 cell/L and the
NPDES Permit No. MA0103284 2023 Draft Permit
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toxicity data are no longer above closure levels (80 μg STX
equiv./100 g).
(f) If an ARRS is commenced, the Permittee shall submit a
written report with the monthly DMR occuring 60 days
following the completion of the survey.
(2) Pseudo-nitzschia spp.
Pseudo-nitzschia shall continue to be identified and enumerated using the
screened, rapid-analysis method detailed in the 2021 QAPP 32 .
Pseudo-nitzschia abundance shall be reported as all Pseudo-nitzschia cells at
the genus level regardless of assumed species or cell size, not just Pseudo-
nitzschia pungens or Pseudo-nitzschia multiseries type cells. When comparing
Pseudo-nitzschia abundance across years, past abundances should be updated
to reflect all Pseudo-nitzschia spp. cells when the historical monitoring dataset
allows.
i. A plankton sample to measure the toxin domoic acid that some
species of Pseudo-nitzschia produce shall be collected during
the routine water column sampling at each monitoring station.
This sample shall be collected by passing at least 20 L of
surface seawater through a 20 μm plankton net (equipped with a
flow meter) or mesh screen (estimated by bucket or carboy
volumes) and storing the concentrated sample chilled at 4 °C in
the dark (fridge).
These samples shall be tested for the presence or absence of
domoic acid using a Scotia Rapid Test, similar method to the
Scotia Rapid Test, or liquid chromatography – tandem mass
spectrometry, if one of the following are true:
(a) Pseudo-nitzschia spp. cell counts at the corresponding station
exceed 15,000 Pseudo-nitzschia cells/L.
(b) Pseudo-nitzschia australis is possibly present in the
corresponding station sample at elevated abundance deduced
32 Libby PS, Whiffen-Mansfield AD, Nichols KB, Lescarbeau GR, Borkman DG, Turner JT, 2021, Quality
Assurance Project Plan (QAPP) for water column monitoring 2020-2022: Tasks 4-7 and 10, Revision 1. Boston,
Massachusetts Water Resources Authority. Report 2021-01. 66p. https://www.mwra.com/harbor/enquad/pdf/2021-
01.pdf
NPDES Permit No. MA0103284 2023 Draft Permit
Page 61 of 68
from the presence of over 2,000 cells/L of large Pseudo-
nitzschia cells equal to or greater than 3 μm in width.
(c) There is a co-occurring shellfish harvest closure due to
domoic acid or elevated Pseudo-nitzschia cell abundance in
Massachusetts Bay.
ii. MWRA shall conduct Pseudo-nitzschia Rapid Response Study
based on the following one or more of the following scenarios
occuring:
(a) MWRA shall begin weekly surveys for Pseudo-nitzschia
when the information suggests:
(i) If a bloom of Pseudo-nitzschia is present in Massachusetts
Bay or possibly imminent from observations in waters
north of Massachusetts Bay.
(ii) If Pseudo-nitzschia spp. cell counts exceed 15,000 cells/L
and/or P. australis is likely present in samples and domoic
acid is present in the 20 μm concentrated sample.
(iii)If domoic acid in blue mussels is over 1 mg toxin per 100
g shellfish meat in Cohasset, Scituate, or Marshfield MA
DMF stations.
(iv) If domoic acid in blue mussels is equal to or exceeds 2 mg
toxin per 100 g shellfish meat in any MA DMF stations.
(b) MWRA shall assess the availability of a species-specific DNA
probe to confirm the presence of the highly toxic and
problematic species Pseudo-nitzschia australis and, if
available, MWRA shall implement this probe into routine
water column sampling and Pseudo-nitzschia Rapid Response
Sampling.
NPDES Permit No. MA0103284 2023 Draft Permit
Page 62 of 68
iii. Once a Pseudo-nitzschia Rapid Response Study is initiated, it
will continue weekly samples until all stations are below
15,000 cells/L and no domoic acid is present through the Rapid
Scotia Test or equivalent method.
iv. If a Pseudo-nitzschia Rapid Response Study is commenced, the
Permittee shall submit a written report with the monthly DMR
occurring 60 days following the completion of the survey.
(3) Dinophysis spp.
Dinophysis shall continue to be enumerated as previously described with the
routine water column monitoring.
Dinophysis spp. shall be added to list of harmful or nuisance alga of interest
reported from the screened, rapid-analysis samples on page 43 of the MWRA
QAPP Water Column Monitoring 2020 – 2022.
If cell counts of Dinophysis exceeds 100,000 cells/L, then this shall be reported
by the Permittee within 45 days with the next monthly DMR.
(4) Phaeocystis pouchetii
Phaeocystis pouchetii shall continue to be enumerated as previously described
with the routine water column monitoring.
Phaeocystis pouchetii shall continue to be reported as part of the list of harmful or
nuisance alga of interest from the screened, rapid-analysis samples on page 43 of
the MWRA QAPP Water Column Monitoring 2020 – 2022.
i. If Phaeocystis pouchetii cell counts exceed 6 x 106 cells/L, then
this shall be reported by the Permittee within 45 days with the
next monthly DMR. If Phaeocystis pouchetii cell counts exceed
this threshold and there is a subsequent decrease in dissolved
oxygen concentrations or nearby foam observed on beaches or
other suspected environmental impacts from a Phaeocystis
pouchetii bloom, then MWRA shall investigate the probable
Phaeocystis pouchetii bloom further by collecting additional
water samples.
(5) Karenia mikimotoi
Karenia mikimotoi shall continue to be enumerated as previously described with
the routine water column monitoring.
NPDES Permit No. MA0103284 2023 Draft Permit
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Karenia mikimotoi shall be added to list of harmful or nuisance alga of interest
reported from the screened, rapid-analysis samples on page 43 of the MWRA
QAPP Water Column Monitoring 2020 – 2022.
i. If Karenia mikimotoi cell counts exceed 10,000 cells/L, then
this shall be reported by the Permittee within 45 days with the
next monthly DMR. If Karenia mikimotoi cell counts exceed
this threshold and there is a subsequent decrease in dissolved
oxygen concentrations, then MWRA shall investigate the
probably Karenia mikimotoi bloom further by collecting water
samples throughout the water column, including the subsurface
chlorophyll maximum and bottom, in order to enumerate the
presence of Karenia mikimotoi which is able to vertically
migrate through the water column.
(6) Margalefidinium polykrikoides (formerly known as Cochlodinium
polykrikoides )
Margalefidinium polykrikoides shall continue to be enumerated as previously
described with the routine water column monitoring.
Margalefidinium polykrikoides shall be added to list of harmful or nuisance alga
of interest reported from the screened, rapid-analysis samples on page 43 of the
MWRA QAPP Water Column Monitoring 2020 – 2022.
i. If Margalefidinium polykrikoides cell counts exceed 1,000
cells/L, then this shall be reported by the Permittee within 45
days with the next monthly DMR. If Margalefidinium
polykrikoides cell counts exceed this threshold and there is a
subsequent decrease in dissolved oxygen concentrations, then
MWRA shall investigate the probable Margalefidium
polykrikoides bloom further by collecting water samples
throughout the water column, including the subsurface
chlorophyll maximum and bottom, in order to enumerate the
presence of Margalefidinium polykrikoides which is able to
vertically migrate through the water column
g. Continuous measurement of biological parameters
MWRA shall track data from the Northeastern Regional Association of Coastal Ocean
Observing System (NERACOOS) monitoring buoy off Cape Ann, NERACOOS A01,
and the NOAA weather buoy, 44013, just south of the outfall site.
h. Remote sensing
NPDES Permit No. MA0103284 2023 Draft Permit
Page 64 of 68
Monitor sea surface temperature and chlorophyll through remote sensing via satellite
imagery. Imagery can be used in the synthesis of water column monitoring and
interpreting unusual events.
i. Floatables observations
The MWRA should continue floatables observations to ensure that the discharge
continues to meet water quality standards for aesthetics.
j. Data Evaluation
Emphasize, identify and quantify trends and emerging issues or threats, trend analyses to
receive additional focus including sophisticated analytical methods (e.g., general additive
models).
k. Modifications to Ambient Monitoring Plan
By November 15 of each year, the Permittee or any member of the public shall submit a
list of any proposed modifications to the ambient monitoring plan to EPA and MassDEP.
These modifications shall become effective upon written approval by EPA and the
MassDEP.
(1) The Permittee or any member of the public may also propose
modifications at any time. Such modifications will become effective thirty
(30) days after the Permittee provides written notice to EPA and
MassDEP, unless there is written objection from EPA or MassDEP. Such
approvals will be effective until EPA and MassDEP take action on the
Permittee's or the public's next annual request.
l. Annual Report
The results of all monitoring required by the Ambient Monitoring Plan shall be reported
to EPA and MassDEP on an annual basis. Reporting on HABs and nuisance algae shall
be reported as an attachment to the monthly DMR 60 days after the survey is concluded.
Raw data shall be made available upon request by EPA, MassDEP, NMFS or any
member of the public.
m. Special Studies
EPA and/or MassDEP may propose special studies in response to the Water Column
Monitoring Results or other concerns in Massachusetts Bay. The special studies shall be
specific to the MWRA discharge.
7. Dye studies for CSO Treatment Facilities discharge locations
The Permittee shall conduct a dye study at each of the CSO Treatment Facility discharge
locations once during the 5-year permit term to determine the dilution at the point of
NPDES Permit No. MA0103284 2023 Draft Permit
Page 65 of 68
discharge during the applicable hydraulic condition in the WQS at 314 CMR 4.03(3). The
Permittee should consult with MassDEP as to the applicable hydraulic condition for each
discharge location. The completed dye studies must be submitted by MWRA six months
before the end of the permit term (concurrent with NPDES application).
J. REPORTING REQUIREMENTS
Unless otherwise specified in this Permit, the Permittee shall submit reports, requests, and
information and provide notices in the manner described in this section.
1. Submittal of DMRs Using NetDMR
The Permittee shall continue to submit its monthly monitoring data in discharge monitoring
reports (DMRs) to EPA and the State electronically using NetDMR no later than the 15th day
of the month. When the Permittee submits DMRs using NetDMR, it is not required to submit
hard copies of DMRs to EPA or the State. NetDMR is accessible through EPA’s Central
Data Exchange at https://cdx.epa.gov /.
2. Submittal of Reports as NetDMR Attachments
Unless otherwise specified in this Permit, the Permittee and Co-permittees shall
electronically submit all reports to EPA as NetDMR attachments rather than as hard copies.
See Part I.J.8. for more information on State reporting. Because the due dates for reports
described in this Permit may not coincide with the due date for submitting DMRs (which is
no later than the 15th day of the month), a report submitted electronically as a NetDMR
attachment shall be considered timely if it is electronically submitted to EPA using NetDMR
with the next DMR due following the report due date specified in this Permit.
3. Submittal of Industrial User and Pretreatment Related Reports
a. Prior to 21 December 2025, all reports and information required of the Permittee in
the Industrial Users and Pretreatment Program section of this Permit shall be
submitted to the Pretreatment Coordinator in EPA Region 1 Water Division (WD).
Starting on 21 December 2025, these submittals must be done electronically as
NetDMR attachments and/or using EPA’s NPDES Electronic Reporting Tool
(“NeT”), or another approved EPA system, which will be accessible through
EPA’s Central Data Exchange at https://cdx.epa.gov/ . These requests, reports and
notices include:
(1) Annual Pretreatment Reports,
(2) Pretreatment Reports Reassessment of Technically Based Industrial
Discharge Limits Form,
(3) Revisions to Industrial Discharge Limits,
(4) Report describing Pretreatment Program activities, and
(5) Proposed changes to a Pretreatment Program.
NPDES Permit No. MA0103284 2023 Draft Permit
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b. This information shall be submitted to EPA WD as a hard copy at the following
address:
U.S. Environmental Protection Agency
Water Division
Regional Pretreatment Coordinator
5 Post Office Square - Suite 100 (06-03)
Boston, MA 02109-3912
4. Submittal of Biosolids/Sewage Sludge Reports
By February 19 of each year, the Permittee must electronically report their annual
Biosolids/Sewage Sludge Report for the previous calendar year using EPA’s NPDES
Electronic Reporting Tool (“NeT”), or another approved EPA system, which is accessible
through EPA’s Central Data Exchange at https://cdx.epa.gov/ .
5. Submittal of Requests and Reports to EPA Water Division (WD)
a. The following requests, reports, and information described in this permit shall be
submitted to the NPDES Applications Coordinator in EPA Water Division (WD):
(1) Transfer of permit notice;
(2) Request for changes in sampling location;
(3) Request for reduction in testing frequency;
(4) Report on unacceptable dilution water / request for alternative dilution
water for WET testing;
(5) Report of new industrial user commencing discharge; and
(6) Report received from existing industrial user.
b. These reports, information, and requests shall be submitted to EPA WD
electronically at R1NPDESReporting@epa.gov .
6. Submittal of Sewer Overflow and Bypass Reports and Notifications
c. The Permittee shall submit required reports and notifications under Part II.B.4.c,
for bypasses, and Part II.D.1.e, for sanitary sewer overflows (SSOs) electronically
using EPA’s NPDES Electronic Reporting Tool (“NeT”), which will be accessible
through EPA’s Central Data Exchange at https://cdx.epa.gov/ .
7. State Reporting
Duplicate signed copies of all WET test reports shall be submitted to the Massachusetts
Department of Environmental Protection, Division of Watershed Management, at the
following address:
NPDES Permit No. MA0103284 2023 Draft Permit
Page 67 of 68
Massachusetts Department of Environmental Protection
Bureau of Water Resources
Division of Watershed Management
8 New Bond Street
Worcester, Massachusetts 01606
8. Verbal Reports and Verbal Notifications
a. Any verbal reports or verbal notifications, if required in Parts I and/or II of this
permit, shall be made to both EPA and to the State. This includes verbal reports
and notifications which require reporting within 24 hours (e.g., Part II.B.4.c.(2),
Part II.B.5.c.(3), and Part II.D.1.e).
b. Verbal reports and verbal notifications shall be made to:
EPA ECAD at 617-918-1510
and
MassDEP Emergency Response at 888-304-1133
K. STATE 401 CERTIFICATION CONDITIONS
1. This Permit is in the process of receiving state water quality certification issued by
MassDEP under § 401(a) of the CWA and 40 CFR § 124.53. EPA will incorporate
appropriate State water quality certification requirements (if any) into the Final Permit.
2. MassDEP has approved a pH Adjustment Demonstration Project. The pH limits in the Permit
are 6.0 to 8.5 S.U. and the following requirements must be met based on MassDEP’s
approval letter:
• MWRA shall provide ambient pH monitoring both outside the area of discharge
influence and within the area of discharge influence to confirm compliance with
SWQS.
• Minimum sampling frequency and duration shall be monthly for a period of six
months immediately following the pH limit approval or as otherwise approved by
MassDEP.
• Measurements of pH shall be taken using probes calibrated just prior to each use and
at documented and representative locations.
• Whenever feasible, sampling should be conducted during dry weather conditions
(little or no antecedent precipitation). Data shall be submitted to MassDEP’s email
portal on a monthly basis ( wqdata.submit@state.ma.us ).
• Any and all exceedances of SWQS for pH shall be immediately reported to MassDEP
via that same email portal.
• Following the six-month period, MassDEP shall evaluate the submitted data to
determine the need for additional monitoring and/or follow up.
NPDES Permit No. MA0103284 2023 Draft Permit
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3. The Permittee and CSO-responsible Co-permittees must implement their preliminary and
final CSO Public Notification Plans as approved by MassDEP and shall meet all other
applicable requirements of 314 CMR 16.00.