Task 2: wetland delineation and sediment sampling

Town of Winthrop · from the Town's website · 15 pages · 3.1 MB
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1 
81 Technology Park Dr., East Falmouth, MA 02536 
Direct Extension: (508) 495-6221 
Main Telephone: (508) 540-8080 
FAX: (508) 540-1001 
e-mail:lweishar@whgrp.com 
www.woodsholegroup.com 
MEMORANDUM 
Date: May 17 2016 
To: Mr. Art Leventis 
From: Lee Weishar, Ph.D.; PWS 
Re: Task 3 Wetlands Delineation Memorandum and Sediment Sampling 
Introduction 
On April 27 , 2016 , Woods Hole Group conducted a site assessment and wetland delineation of
the coastal resource areas along the western side of Coughlin Park in Winthrop , MA for the
Town of Winthrop . The work was performed at low tide to ensure all resource areas were visible
and the assessment and delineation could be performed accurately. Figure 1 shows the location
of Coughlin Park and identifies the area covered by the assessment and delineation. 
Woods Hole Group delineated and flagged salt marsh, rocky intertidal, and coastal bank resource
areas along the western shoreline of Coughlin Park. There is also a coastal beach seaward of the
toe of the coastal bank. Each resource area will be described below in this memorandum.
Additionally, a draft map of the locations of these resource areas is provided in Figure 2. This
draft map is meant to help facilitate the discussion of the field work and the description of the
resource areas and is not to be used for detailed planning or design purposes. The flags set out
during the resource area delineation will be picked up and accurately mapped by the surveyor. 
Salt Marsh delineation: 
The Salt Marsh delineation was performed pursuant to 310 CMR 10.32 (2), to include all plants
adapted to saline conditions. The dominant plant observed at the time of the delineation was salt
marsh cord grass ( Spartina alterniflora ). Because it is so early in the season, the S. alterniflora 
was just beginning to sprout again for this growing season . However, the extent of the salt
marsh could be discerned from the partially remaining S. alterniflora stems from last year.
Flagging stations were marked as M-1 to M-40 (Figure 2). 
The plant density throughout the salt marsh area was variable. At the far southern end (M-1 to
M-6 and M-36 to M-40; Figure 2), the S. alterniflora stems are sparse, and were growing in a
mix of sand and cobble (Figure 3). This sparse area was separated from a denser section of S.
alterniflora that was growing in peat by a section of cobble devoid of salt marsh (Figure 4). This
bare section is located in the drainage path of the large outfall pipe extending from the end of the
stone revetment. This area is captured by wetland flags M-27 to M-32 (Figure 2). The denser,
more robust area of S. alterniflora north of this drainage area also impounds a tidal pool area
between the salt marsh and coastal beach (M-9 to M-15; Figure 2); the S. alterniflora grass in

this area had more new shoot growth than in the sparse, more cobble dominated areas (Figure 5).
The tidal pool contained a variety of snails, crabs, and macroalgae, as well as schools of small
fish. 
Figure 1. Locator Map. The left-hand figure shows Coughlin Park’s location in the regional
context, while the right-hand figure shows the area of Coughlin Park that was evaluated
during the April 27, 2016 site visit and wetland delineation.

Figure 2. Estimated locations of mapped wetland resources at Coughlin Park.

Figure 3. Sparse S. alterniflora growing at the southern end of the salt marsh . 
Figure 4. Sparse and dense areas of S. alterniflora separated by drainage from outfall pipe. 
Sparse 
S. alterniflora 
in cobble 
Dense 
S. alterniflora 
in peat 
Drainage
Path

Figure 5. Dense section of S. alterniflora with new shoots in the salt marsh fronting an
impounded tide pool. 
Coastal Bank Delineation: 
The Coastal Bank delineation was performed pursuant to 310 CMR 10.30 (2). The top of bank
was marked with f lagging stations labeled TOP -1 to TOP-35, in a south to north direction, while
the toe of bank was marked with flagging stations labeled BASE-1 to BASE-26 in a north to
south direction (Figure 2). TOP-1 and BASE-26 are located adjacent to the end of the large
stone revetment along Grand View Avenue. Most of the top of the Coastal Bank is lawn, and is
severely undercut and eroding (Figure 6). Much of this area is fronted by deteriorating hay bales
that were placed for runoff control during the construction of the updated recreation facilities at
the park last year. The ongoing erosion has exposed sidewalk framing material, filter fabric, and
roots, among other objects, as the bank continues to recede. The exception to this, however, is
the northern end of the Coastal Bank that was mapped (TOP-33 to TOP-35) less scarped and is
an area of transition with a mix of grass and cobble berm (Figure 7). 
Three samples were collected from the coastal bank to be analyzed for grain size; these were
labeled BANK-1, BANK-2, and BANK-3. BANK-1 was collected from the southern end of the
Coastal Bank, BANK-2 was collected from approximately the middle portion of the Coastal
Bank, and BANK-3 was collected from the northern end of the Coastal Bank (Figure 2). Figure
8 shows an example of the different soil layers observed in the exposed face of the Coastal Bank.

Figure 6. Eroding coastal bank along southwestern edge of Coughlin Park. 
Figure 7. Northern end of Coastal Bank (TOP-35) where it transitions to a cobble berm.

Figure 8. Grain size sample collected from BANK-3. Note the different soil layers,
including a significant clay layer at the bottom. 
Rocky Intertidal Shore Delineation: 
The Rocky Intertidal Shore delineation was performed pursuant to 310 CMR 10.31 (2), to
include all boulder strewn areas between the mean high water line and the mean low water line.
Three Rocky Intertidal Shore areas were marked with flagging stations labeled RIZ-1 to RIZ-4,
RIZ-5 to RIZ-8, and RIZ-9 to RIZ-12 (Figure 2). The most southern Rocky Intertidal Shore area
(RIZ-1 to RIZ-4) was a cluster of large boulders located between the revetment and the outfall
pipe. The next Rocky Intertidal Shore area (RIZ-5 to RIZ-8) was a cluster of large boulders
around the end of the outfall pipe. The third, and largest of the Rocky Intertidal Shore areas, was
comprised of small boulders (10 to 24 inches) located in a 15- to 20-foot wide band landward of
the salt marsh (Figure 9).

Figure 9. Larger area of Rocky Intertidal Shore (RIZ-9 to RIZ-12) landward of the salt
marsh. 
Coastal Beach: 
The Coastal Beach at the site was not delineated explicitly, however, all areas seaward of the toe
of the bank that are not delineated as Salt Marsh or Rock Intertidal Shore are in fact Coastal
Beach pursuant to 310 CMR 10.27 (2). In addition to the grain size samples collected from the
Coastal Bank as described above, four additional sediment samples were collected from the
Coastal Beach for grain size analysis (BEACH-1 to BEACH-4; Figure 2). BEACH-1 was
collected seaward of BANK-1, and was predominantly sand. BEACH-2 was collected seaward
of BANK-2, and was predominantly gravel and cobble with some sand. Finally, BEACH-3 and
BEACH-4 were collected seaward of BANK-3, which had a mix of finer sand and gravel; the
sampling team opted to collect two sediment samples located at different elevations of the
Coastal Beach to more appropriately capture the range in grain size observed at the site. 
Grain Size Analysis 
The results of the grain size analyses are attached to this memorandum. The results of the analyses show
that the sediment have a cobble and gravel fraction that is intermixed with sand.

Client: Woods Hole Group
Project: Sand Samples
Location: --- Project No: GTX-304691
Boring ID: ---
Sample ID: Bank #1
Depth : ---
Sample Type: bag
Test Date: 05/10/16
Test Id: 376419
Tested By: jbr
Checked By: emm
Test Comment: ---
Visual Description: Moist, brown sand with silt and gravel
Sample Comment: ---- 
Particle Size Analysis - ASTM D422 
printed 5/13/2016 11:51:12 AM 
0
10
20
30
40
50
60
70
80
90
100
0.001 0.01 0.1 1 10 100 1000
Percent Finer
Grain Size (mm) 
1.5 in
1 in
0.75 in
0.5 in
0.375 in
#4
#10
#20
#40
#60
#100
#200 
% Cobble
---
% Gravel
40.9
% Sand
48.3
% Silt & Clay Size
10.8 
Sieve Name Sieve Size, mm Percent Finer Spec. Percent Complies 
1.5 in
1 in
0.75 in
0.5 in
0.375 in
#4
#10
#20
#40
#60
#100
#200
37.50
25.00
19.00
12.50
9.50
4.75
2.00
0.85
0.42
0.25
0.15
0.075
100
87
82
74
69
59
52
44
33
22
15
11 
Coefficients 
D =22.0655 mm 85
D =5.0846 mm 60
D =1.5348 mm 50
D =0.3755 mm 30
D =0.1542 mm 15
D =N/A 10
C =N/A u C =N/A c 
Classification 
ASTM N/A
AASHTO Stone Fragments, Gravel and Sand
(A-1-b (0)) 
Sample/Test Description 
Sand/Gravel Particle Shape : ROUNDED
Sand/Gravel Hardness : HARD

Client: Woods Hole Group
Project: Sand Samples
Location: --- Project No: GTX-304691
Boring ID: ---
Sample ID: Bank #2
Depth : ---
Sample Type: bag
Test Date: 05/10/16
Test Id: 376420
Tested By: jbr
Checked By: emm
Test Comment: ---
Visual Description: Moist, very dark brown silty sand
Sample Comment: --- 
Particle Size Analysis - ASTM D422 
printed 5/13/2016 11:52:04 AM 
0
10
20
30
40
50
60
70
80
90
100
0.001 0.01 0.1 1 10 100 1000
Percent Finer
Grain Size (mm) 
0.5 in
0.375 in
#4
#10
#20
#40
#60
#100
#200 
% Cobble
---
% Gravel
1.1
% Sand
51.4
% Silt & Clay Size
47.5 
Sieve Name Sieve Size, mm Percent Finer Spec. Percent Complies 
0.5 in
0.375 in
#4
#10
#20
#40
#60
#100
#200
12.50
9.50
4.75
2.00
0.85
0.42
0.25
0.15
0.075
100
100
99
98
96
91
83
71
47 
Coefficients 
D =0.2826 mm 85
D =0.1092 mm 60
D =0.0809 mm 50
D =N/A 30
D =N/A 15
D =N/A 10
C =N/A u C =N/A c 
Classification 
ASTM N/A
AASHTO Silty Soils (A-4 (0)) 
Sample/Test Description 
Sand/Gravel Particle Shape : ---
Sand/Gravel Hardness : ---

Client: Woods Hole Group
Project: Sand Samples
Location: --- Project No: GTX-304691
Boring ID: ---
Sample ID: Bank #3
Depth : ---
Sample Type: bag
Test Date: 05/10/16
Test Id: 376421
Tested By: jbr
Checked By: emm
Test Comment: ---
Visual Description: Moist, dark brown silty sand with gravel
Sample Comment: --- 
Particle Size Analysis - ASTM D422 
printed 5/13/2016 11:53:14 AM 
0
10
20
30
40
50
60
70
80
90
100
0.001 0.01 0.1 1 10 100 1000
Percent Finer
Grain Size (mm) 
1.5 in
1 in
0.75 in
0.5 in
0.375 in
#4
#10
#20
#40
#60
#100
#200 
% Cobble
---
% Gravel
38.9
% Sand
41.4
% Silt & Clay Size
19.7 
Sieve Name Sieve Size, mm Percent Finer Spec. Percent Complies 
1.5 in
1 in
0.75 in
0.5 in
0.375 in
#4
#10
#20
#40
#60
#100
#200
37.50
25.00
19.00
12.50
9.50
4.75
2.00
0.85
0.42
0.25
0.15
0.075
100
94
84
76
72
61
55
48
41
33
26
20 
Coefficients 
D =19.4975 mm 85
D =4.1026 mm 60
D =1.0893 mm 50
D =0.2021 mm 30
D =N/A 15
D =N/A 10
C =N/A u C =N/A c 
Classification 
ASTM N/A
AASHTO Stone Fragments, Gravel and Sand
(A-1-b (0)) 
Sample/Test Description 
Sand/Gravel Particle Shape : ROUNDED
Sand/Gravel Hardness : HARD

Client: Woods Hole Group
Project: Sand Samples
Location: --- Project No: GTX-304691
Boring ID: ---
Sample ID: Beach #1
Depth : ---
Sample Type: bag
Test Date: 05/10/16
Test Id: 376415
Tested By: jbr
Checked By: emm
Test Comment: ---
Visual Description: Moist, olive sand
Sample Comment: --- 
Particle Size Analysis - ASTM D422 
printed 5/13/2016 11:40:18 AM 
0
10
20
30
40
50
60
70
80
90
100
0.001 0.01 0.1 1 10 100 1000
Percent Finer
Grain Size (mm) 
0.75 in
0.5 in
0.375 in
#4
#10
#20
#40
#60
#100
#200 
% Cobble
---
% Gravel
11.6
% Sand
88.1
% Silt & Clay Size
0.3 
Sieve Name Sieve Size, mm Percent Finer Spec. Percent Complies 
0.75 in
0.5 in
0.375 in
#4
#10
#20
#40
#60
#100
#200
19.00
12.50
9.50
4.75
2.00
0.85
0.42
0.25
0.15
0.075
100
97
95
88
85
76
41
12
1
0.3 
Coefficients 
D =2.2304 mm 85
D =0.6188 mm 60
D =0.5063 mm 50
D =0.3471 mm 30
D =0.2651 mm 15
D =0.2308 mm 10
C =2.681 u C =0.844 c 
Classification 
ASTM Poorly graded sand (SP)
AASHTO Stone Fragments, Gravel and Sand
(A-1-b (1)) 
Sample/Test Description 
Sand/Gravel Particle Shape : ROUNDED
Sand/Gravel Hardness : HARD

Client: Woods Hole Group
Project: Sand Samples
Location: --- Project No: GTX-304691
Boring ID: ---
Sample ID: Beach #2
Depth : ---
Sample Type: bag
Test Date: 05/10/16
Test Id: 376416
Tested By: jbr
Checked By: emm
Test Comment: ---
Visual Description: Moist, dark brown gravel with sand
Sample Comment: --- 
Particle Size Analysis - ASTM D422 
printed 5/13/2016 11:42:25 AM 
0
10
20
30
40
50
60
70
80
90
100
0.001 0.01 0.1 1 10 100 1000
Percent Finer
Grain Size (mm) 
2 in
1.5 in
1 in
0.75 in
0.5 in
0.375 in
#4
#10
#20
#40
#60
#100
#200 
% Cobble
---
% Gravel
59.2
% Sand
40.3
% Silt & Clay Size
0.5 
Sieve Name Sieve Size, mm Percent Finer Spec. Percent Complies 
2 in
1.5 in
1 in
0.75 in
0.5 in
0.375 in
#4
#10
#20
#40
#60
#100
#200
50.00
37.50
25.00
19.00
12.50
9.50
4.75
2.00
0.85
0.42
0.25
0.15
0.075
100
94
81
72
59
53
41
33
24
12
5
1
0.5 
Coefficients 
D =28.0541 mm 85
D =12.7171 mm 60
D =8.1061 mm 50
D =1.4489 mm 30
D =0.5020 mm 15
D =0.3618 mm 10
C =35.150 u C =0.456 c 
Classification 
ASTM Poorly graded gravel with sand (GP)
AASHTO Stone Fragments, Gravel and Sand
(A-1-a (1)) 
Sample/Test Description 
Sand/Gravel Particle Shape : ROUNDED
Sand/Gravel Hardness : HARD

Client: Woods Hole Group
Project: Sand Samples
Location: --- Project No: GTX-304691
Boring ID: ---
Sample ID: Beach #3
Depth : ---
Sample Type: bag
Test Date: 05/10/16
Test Id: 376417
Tested By: jbr
Checked By: emm
Test Comment: ---
Visual Description: Moist, very dark olive gray sand
Sample Comment: --- 
Particle Size Analysis - ASTM D422 
printed 5/13/2016 11:43:45 AM 
0
10
20
30
40
50
60
70
80
90
100
0.001 0.01 0.1 1 10 100 1000
Percent Finer
Grain Size (mm) 
0.75 in
0.5 in
0.375 in
#4
#10
#20
#40
#60
#100
#200 
% Cobble
---
% Gravel
5.6
% Sand
94.1
% Silt & Clay Size
0.3 
Sieve Name Sieve Size, mm Percent Finer Spec. Percent Complies 
0.75 in
0.5 in
0.375 in
#4
#10
#20
#40
#60
#100
#200
19.00
12.50
9.50
4.75
2.00
0.85
0.42
0.25
0.15
0.075
100
99
98
94
76
40
13
7
1
0.3 
Coefficients 
D =3.0387 mm 85
D =1.3694 mm 60
D =1.0829 mm 50
D =0.6578 mm 30
D =0.4423 mm 15
D =0.3245 mm 10
C =4.220 u C =0.974 c 
Classification 
ASTM Poorly graded sand (SP)
AASHTO Stone Fragments, Gravel and Sand
(A-1-b (1)) 
Sample/Test Description 
Sand/Gravel Particle Shape : ROUNDED
Sand/Gravel Hardness : HARD

Client: Woods Hole Group
Project: Sand Samples
Location: --- Project No: GTX-304691
Boring ID: ---
Sample ID: Beach #4
Depth : ---
Sample Type: bag
Test Date: 05/10/16
Test Id: 376418
Tested By: jbr
Checked By: emm
Test Comment: ---
Visual Description: Moist, gray sand with gravel
Sample Comment: --- 
Particle Size Analysis - ASTM D422 
printed 5/13/2016 11:45:42 AM 
0
10
20
30
40
50
60
70
80
90
100
0.001 0.01 0.1 1 10 100 1000
Percent Finer
Grain Size (mm) 
1.5 in
1 in
0.75 in
0.5 in
0.375 in
#4
#10
#20
#40
#60
#100
#200 
% Cobble
---
% Gravel
35.8
% Sand
64.1
% Silt & Clay Size
0.1 
Sieve Name Sieve Size, mm Percent Finer Spec. Percent Complies 
1.5 in
1 in
0.75 in
0.5 in
0.375 in
#4
#10
#20
#40
#60
#100
#200
37.50
25.00
19.00
12.50
9.50
4.75
2.00
0.85
0.42
0.25
0.15
0.075
100
90
85
74
69
64
60
51
28
5
0
0.1 
Coefficients 
D =18.8262 mm 85
D =1.9725 mm 60
D =0.8147 mm 50
D =0.4476 mm 30
D =0.3158 mm 15
D =0.2823 mm 10
C =6.987 u C =0.360 c 
Classification 
ASTM Poorly graded sand with gravel (SP)
AASHTO Stone Fragments, Gravel and Sand
(A-1-b (1)) 
Sample/Test Description 
Sand/Gravel Particle Shape : ANGULAR
Sand/Gravel Hardness : HARD