Valley Sports Well

P-4

P-3

P-2

P-1

9-78

OW-3OW-2

AR-02

CLF-1

PT-10

MW-8A

LF-20DCLF-3B

CLF-2C

ML-3-1ML-1-1

MW-S27MW-S29

MW-S28

MW-S24

MW-S08

MW-S09

MW-S04

MW-S17

MW-S07

MW-S02

MW-S05

MW-S22

CLF-101

CLF-102

CLF-103

CLF-106

CLF-104

CLF-105

PT-04B1

GZW-6-1

PT-11B1P-2A

P-1A

MW-2P-3A

CLF-2B

CLF-3A

CLF-2A

MW-S23

MW-T24

CLF-107

GZW-9-2GZW-9-1

GZW-8-1

MW-SD27MW-SD29

MW-SD17

MW-SM13MW-SD13

GZW-11-1

ASBRV-D

ASBRV-U2

ASBRV-U1MW-BS04

MW-BS17

MW-BS13

MW-BS22

MW-BS01

MW-BS02

LF-18DBRLF-20DBR

GZW-11-2

LF-20SBRLF-18SBR

A'

B

B'

A

B-06 0.81 (2015)

OW-1 15.4 (2013)

MW-1 15.7 (2013)

J2-B1 1.16 (2013)

PT-09 1.85 (2015)

SW-101 0.18 (2015)

MW-S26 5.15 (2015)

MW-S32 1.82 (2015)

MW-SD37 4.3 (2015)

MW-S30 0.73 (2015)MW-S06 1.06 (2013)

MW-SD01 3.8 (2013)

MW-S15 1.19 (2015)

SW-102 0.212 (2015)

SW-103 0.234 (2015)

MW-S38 0.346 (2015)

MW-SD34 47.4 (2015)

LF-18D 8.40B (2015)

MW-S36 <0.147 (2015)

MW-S39 <0.147 (2015)

MW-S14 <0.156 (2015)

J2-B2 0.958 (2013)

MW-S01 9.31 (2013)

MW-S37 0.457 (2015)

MW-SD38 1.36 (2015)

MW-SD32 3.27 (2015)

PT-11B1 20.4 (2015)

PT-03B2 0.856 (2015)

MW-S35 <0.142 (2015)

PT-11B3 <0.15 (2013)

PT-11P <0.167 (2013)

MW-SD35 <0.142 (2015)

MW-SD39 <0.147 (2015)

MW-SD36 <0.150 (2015)

PT-11B2 <0.142 (2015)

GZW-7-2 39 (2012)

ML-1-3 10.9 (2013)

GZW-10-2 58 (2015)

MW-BS31 5.64 (2015)

MW-BS28 47.5 (2013)

GZW-8-2 0.199 (2015)MW-BS37 6.02 (2015)

MW-BS32 18.9 (2015)MW-BS34 2.53 (2015)

PT-03B1 5.64 (2015) MW-BM15 3.31 (2015)

MW-BM03 30.8 (2013)

MW-BS15 89.6 (2015)

MW-BS14 4.54 (2015)

MW-BS26 5.59 (2015)

MW-BS25 18.1 (2013)

MW-BS03 12.2 (2013)

MW-BS38 <0.142 (2015)

MW-BS39 <0.147 (2015)

MW-BS36 <0.150 (2015)

MW-BS35 <0.142 (2015)

J3-B1

MW-SD26 2.92 (2015)

MW-BS40 0.182 (2015)MW-SD40 42.3 (2015)MW-S40 0.468 (2015)

5

1

20

10

30

50

40

0.46

60

70 80

0.46

1

5

30

20

1

50

40

30

40

50

510

0.46

Q:\G

ISPr

ojects

\BR0

090-N

MISit

e\Proj

ects\

Upda

tes_2

015\F

06_d

iox1-4

_con

tours_

BR_z

oom_

11x1

7.mxd

DRAFT

Legend@A Monitoring Well

@A Monitoring Well (Destroyed)!( Surface Water Sample Location&% Active Public Water Supply Well&% Non-Active Public Water Supply Well

$B Assabet River Stage Elevation

Surface WaterWetlands1,4-Dioxane ISO ConcentrationContour in BedrockEstimated 1,4-Dioxane ISOConcentration Contour in BedrockCross Section A-A'

Cross Section B-B'0.57 (2015) 1,4-Dioxane Concentrations (µg/L) (Year Collected)

MW-S32

MW-BS32Overburden Monitoring Well

Bedrock Monitoring Well

Note:1. LF-18D and B-06 were sampled by Tetra Tech in August 2015. All other locations were sampled in November 2015 (except where noted)2. "<" indicates less than laboratory reporting limit.3. Only data from Overburden wells were used to draft contours. 0 100 20050

Feet

1,4-Dioxane Concentrations (µg/L) in BedrockGroundwater Most Recent Data Through

January 2016Nuclear Metals, Inc. Superfund Site

Concord, Massachusetts

Figure

6Acton, Massachusetts FEBRUARY 2016

de maximis, inc.

³

Service Layer Credits: Esri, HERE,DeLorme, MapmyIndia, ©OpenStreetMap contributors, andthe GIS user community

ASSABET 1A

MUNICIPAL

WELL

PT-03P, B2, B1

PT-09

PT-10

PT-11P, B3, B2, B1

MW-S15, BS, BM

OW-1

MW-1

MW-S06, SD

MW-S27,SD

MW-07,S

GZW-7-1, 7-2

HB-10,

10S

50

100

150

200

250

0

ELE

VA

TIO

N (F

EE

T N

GV

D)

0

100

150

200

250

ELE

VA

TIO

N (F

EE

T N

GV

D)

50

0

<0.16

3.27

<0.16

<0.16

<0.15

<0.16

0.79J

<0.16

<0.16

<0.167

1.0

4.7

1.0

<1.0

20.4

<1.0

2.0

<1.0

<1.0

<0.0708

124.33

124.49

<1.0

3.2

<1.0

<1.0

1.85

<0.5

<0.5

<0.5

<0.5

<2.0

MWS37,

SD, BS

124.66

<1.0

<1.0

<1.0

<1.0

2.53

1.4

6.7

4.0

<1.0

47.4

OVERBURDEN

TILL

BEDROCK

ASSABET

RIVER

NMI

AA'

500 1000 1500 2000 2500 3000

131.30

130.27

130.48

129.50

129.48

128.24

125.49

125.09

125.38

124.29

124.33

123.74

123.65

123.78

MW-SD34, BS

124.31

-25

MW-S40, SD, BS

124.26

124.33

124.53

EL. 123.53

MCLs ug/L

1,4-DIOXANE 0.46

ROD CLEANUP LEVELS

RISK BASED ug/L

VOCs and 1,4-Dioxane Distribution in

Cross-Section, Data through January 2016

DRAFT

Approximate Scale

Horizontal 1" = 250'

Vertical 1" = 50'

ACTON, MASSACHUSETTS

FIGURE

FEBRUARY 2016

7

NUCLEAR METALS SUPERFUND SITE

CONCORD, MASSACHUSETTS

MW-S36,SD,BS

PT-09

MW-SD34, BS

MW-S32,SD, BS

PT-11P, B3, B2, B1

LF-18D,

SBR,

DBR

CLF-107

CLF-3A, B

0

30

60

90

120

150

0

30

60

90

120

150

ELE

VA

TIO

N (F

EE

T N

GV

D)

ELE

VA

TIO

N (F

EE

T N

GV

D)

ASSABET

RIVER

ASSABET RIVER

SOUTHWEST NORTHEAST

B B'

PT-10

OVERBURDEN

TILL

BEDROCK

124.54

123.66

124.72

126.41

123.59

124.17

124.66

124.44

124.66

124.31

124.29

124.33

124.49

124.42

124.91

124.91

<1.0

<1.0

<1.0

<1.0

<0.0735

<1.0

2.0

<1.0

<1.0

<0.075

<1.0

1.0

<1.0

<1.0

<0.075

<1.0

3.2

<1.0

<1.0

1.85

<1.0

8.6

2.8

5.0

1.82

<1.0

1.1

<1.0

<1.0

3.27

<1.0

2.1

1.5

<1.0

18.9

8.40 B

<0.5

<0.5

<0.5

<0.5

<2.0

<0.16

3.27

<0.16

<0.16

<0.15

<0.16

0.79J

<0.16

<0.16

<0.167

=1.0

4.7

1.0

<1.0

20.4

<1.0

<1.0

<1.0

<1.0

2.53

1.4

6.7

4.0

<1.0

47.4

124.91

MCLs ug/L

1,4-DIOXANE 0.46

0 300 600 900 1200 1500 1800

<1.0

2.0

<1.0

<1.0

<0.0708

2.0

MW-S40,SD,BS

<1.0

<1.0

<1.0

<1.0

0.468

3.2

15

5.9

6.0

42.3

<1.0

<1.0

<1.0

<1.0

0.182

124.26

124.33

124.53

EL. 122.0

EL. 123.53

ROD CLEANUP LEVELS

RISK BASED ug/L

VOCs and 1,4-Dioxane Distribution in

Cross-Section, Data through January 2016

DRAFT

Approximate Scale

Horizontal 1" = 150'

Vertical 1" = 30'

ACTON, MASSACHUSETTS

FIGURE

FEBRUARY 2016

8

NUCLEAR METALS SUPERFUND SITE

CONCORD, MASSACHUSETTS