Attachment_4_-_Back_River_-_Spec_35_20_23_-_1.10.1_Geotechnical_Information__8-28-18.pdf

Figure 1-1. Dredging Area and Sampling Locations for the Langley-DLA Fuel Pier Replacement Project.

Northing Easting

Reference Sites

WBREF 3529595.85 12144144.65 24 Surface Grab -- -- 10/22/2013 1200 -- --

Control Site

CBCON 3624577.47 12183065.81 54 Surface Grab -- -- 10/22/2013 930 -- --

Norfolk Ocean Disposal Site

NODS 3529682.11 12314946.80 70 Water Sample -- -- 10/21/2013 1347 -- --

Langley-DLA Fuel Pier Locations

1 10/19/2013 1050 10 10

2 10/19/2013 1059 9.8 9.8

3 10/19/2013 1107 8.5 8.5

4 10/19/2013 1112 7.4 7.4

5 10/19/2013 1118 8.6 8.6

6 10/19/2013 1125 9.4 9.4

7 10/19/2013 1135 8.3 8.3

1 10/19/2013 900 7.1 Did not keep; opened onboard for observation

2 10/19/2013 924 10.1 9.1

3 10/19/2013 934 10.1 9.1

4 10/19/2013 949 9.6 8.6

5 10/19/2013 954 8.1 7.1

6 10/19/2013 1000 7.5 6.5

7 10/19/2013 1005 8.8 7.8

8 10/19/2013 1015 7.0 6

1 10/19/2013 1412 8.0 6

2 10/19/2013 1421 7.0 6

3 10/19/2013 1428 6.2 6

4 10/19/2013 1433 7.7 6

5 10/19/2013 1439 6.0 6

6 10/19/2013 1445 7.1 6

7 10/19/2013 1454 7.1 6

1 10/19/2013 1252 8.1 6.1

2 10/19/2013 1258 7.0 5

3 10/19/2013 1306 5.3 Did not keep; poor recovery

4 10/19/2013 1310 7.8 6

5 10/19/2013 1318 7.4 6

6 10/19/2013 1325 8.7 6

7 10/19/2013 1330 8.8 6

8 10/19/2013 1337 8.1 6

9 10/19/2013 1345 7.0 6

7 5.5

LANG-04 3562070.71 12113989.88 8.8 8 6

LANG-03 3562304.93 12113641.61 9.3

Date

LANG-02

3561866.02 12113385.67 4.6

3561973.19 12113409.75 5.1

TABLE 2-1. SAMPLING LOCATION COORDINATES AND SEDIMENT RECOVERY INFORMATION FOR VIBRACORING AND REFERENCE SAMPLING

LOCATIONS

Sediment Core Recovery Length (ft)

7 10

LANGLEY-DLA FUEL PIER REPLACEMENT PROJECT, BACK RIVER, VIRGINIA

LANG-01 7 10.5

Time Sediment Sample

Recovery Length (ft)Virginia South State Plane, NAD83 feet Location ID

Actual Water Depth (ft)

Number of Cores Collected

Target Core Length (ft)

Core Number

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

% CLAY % SILT % SAND % GRAVEL

Figure 4-1. Grain size distribution in sediment samples from the Langley-DLA Fuel Pier Replacement and the Willoughby Bank Reference Site.

TABLE 4-6. PHYSICAL CHARACTERISTICS OF SEDIMENT

LANGLEY-DLA FUEL PIER REPLACEMENT PROJECT, BACK RIVER, VIRGINIA

Analyte Unit Average

RL

Willoughby Bank

Reference Site

LANG-01

LANG-01

Field Duplicate

LANG-02 LANG-01/02 LANG-03 LANG-04 LANG-03/04

GRAVEL % -- 2.3 4.8 0 0 0 0 0 4.7

SAND % -- 74.3 5.9 4.3 12.4 11.2 3.1 7.1 7.9

Coarse Sand % -- 0.8 0.5 0 0 0 0 0 0.3

Medium Sand % -- 3 0.3 0.5 1.8 0.1 0.3 0.3 0.2

Fine Sand % -- 70.5 5.1 3.8 10.6 11.1 2.8 6.8 7.4

SILT % -- 18.9 55.7 55.1 49.3 52.5 68 51 52

CLAY % -- 4.5 33.6 40.6 38.3 36.3 28.9 41.9 35.4

SILT+CLAY % -- 23.4 89.3 95.7 87.6 88.8 96.9 92.9 87.4

SPECIFIC GRAVITY -- -- 2.68 2.74 2.73 2.74 2.71 2.68 2.71 2.71

PERCENT MOISTURE % 0.1 30.3 43.8 42.5 37.6 42.4 54.6 48.8 51.6

NOTES: Bold values represent detected concentrations.