04N-040.46/1.4

10-040.66/1.3

27N-012.2/2.0

02N-02ND/ND

16N-013.1/3.4

21N-023.9/3.8

21N-034.2/3.8

21N-043.9/3.6

33N-012.8/3.1

MW-212S13.8/3.4

MW-212S22.8/2.5

MW-136S13.9/3.7

MW-136S2ND/ND

MW-137S24.8/4.7

MW-133S20.26/ND

MW-137S35.6/5.4

MW-135S14.1/4.0

MW-137S15.1/4.7

MW-130S13.9/3.5

MW-130S23.7/3.7

MW-131S12.7/2.5

MW-138S15.4/4.8

MW-138S24.8/4.5MW-139S1

5.2/4.8

MW-154S22.1/2.2

MW-154S112.0/11.0

MW-140S1

MW-135S22.9/4.2

MW-161S31.0/ND

MW-162S30.33/ND

MW-161S13.5/3.4MW-161S23.0/2.6

MW-162S14.4/4.0

MW-162S20.21/ND

MW-166S10.2/ND

MW-166S20.12/ND

MW-174S32.6/2.3

MW-174S13.4/2.9

MW-174S22.4/2.4

MW-184S34.6/4.6

MW-185S34.2/3.9

MW-186S33.9/4.1

MW-188S34.7/6.2

MW-184S13.1/2.9

MW-184S23.2/3.0

MW-185S15.1/4.9MW-185S23.8/4.6

MW-186S21.8/5.5

MW-196S23.3/2.8MW-196S30.09/ND

MW-197S10.9/NDMW-197S2ND/ND

MW-197S30.31/ND

MW-186S14.4/4.6

MW-188S16.8/7.0MW-188S22.7/2.9

MW-193S1

MW-193S212.0/11.0MW-193S365.0/56.0

MW-194S16.4/7.1

MW-194S20.25/NDMW-194S31.1/ND MW-195S1

5.2/4.5MW-195S24.6/4.8MW-195S32.2/2.7

MW-196S15.8/5.9

MW-200S11.1/1.3MW-200S20.081/NDMW-200S30.37/ND

MW-205S12.5/2.9MW-205S24.1/4.0

MW-205S34.1/3.9

MW-133S19.2/8.0

MW-207S112.0/11.0MW-207S22.8/2.5

The 3.1/3.2-μg/L contour is shown as "- -?- -" where inferred and cannot be fully delineated byFirst Quarter 2015 monitoring data.

?

?

?

?

?

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?

?

?

?

?

?

Am

er icanA

ve

PlymouthRd

Burnt TreeR

d

Fri

ends

Rd

Am

eric

an A

ve

Sunset Rd

Roy RdHolstead Rd

Fossil Bed Rd

Am

erican

Way

Coo

n C

anyo

n R

dB

u rn t

Tree

Rd

Mountain General Rd

Orc

hard

St

Mou

ntai

n V

iew

Rd

Ho lstead Rd

Orc

hard

Rd

Bn Ranch Rd

Har

pers

Way

Ha lsted Rd

Hin

kley

Rd

Grass Hopper

Inset 3

PG&E does not agree with the contouring requirements set forth by the Water Board but has completed this map in accordance with the requested standards. The insets below provide PG&E's interpretation of several areas where they believe the requirements of the Water Board create an inaccurate representation of the chromium plume. These interpretations were created using all available hydrogeologic and geochemical information, applications of industry standard, and professional judgment. These displays present the same information and use the same scale as the larger map area.

25-140.97/ND

23-303.3/2.8

23-240.59/ND

C-014.0/3.4

C-033.2/2.6

C-045.3/4.6

DW-03.6/1.8

G-5R2.4/2.2

MW-21B127.0/27.0

MW-30B13.9/3.6

MW-30B28.6/7.7

MW-312.9/2.8

MW-32B16.1/5.8

MW-32B29.0/8.7MW-32S2.9/4.1

MW-433.4/3.4

MW-50A3.3/3.0

MW-50S15.0/15.0

MW-55A0.64/NDMW-55B0.44/ND

MW-55S2.8/2.5

MW-564.9/4.7

MW-68D10.0/10.0

MW-68S1.6/1.9MW-69D

0.85/ND

MW-69S1.7/2.1

MW-70D2.1/2.0

MW-70S1.7/1.5

MW-71D2.2/2.4

MW-71S1.3/1.3

MW-72DND/ND

MW-72S4.8/4.6

MW-79DND/ND

MW-79S5.8/5.6

MW-80D1.4/1.5

MW-80S2.5/2.7

MW-85DND/ND

MW-85S1.8/1.7

MW-86D1.5/1.4

MW-87D3.2/3.1

MW-87S3.1/3.8

MW-88D0.58/ND

MW-88S6.1/5.8

MW-89D0.71/ND

MW-89S3.3/3.2

MW-94D1.5/1.6

MW-94S7.3/6.9

MW-97D1.5/1.8

MW-97S5.1/5.1

MW-107D1.9/ND

C-028.7/7.6

MW1.6

M4.

MW-112D2.7/2.5

MW-112S3.3/3.2

MW-127S12.3/2.4MW-127S21.4/1.3

DW-012.6/2.9

EX-321.4/1.3

MW-50B2.6/2.5

MW-86S4.8/5.0

EX-315.2/4.6

EX-334.7/3.9

G-1R1.6/1.3

G-2R3.9/3.6

MW-21BND/ND

IW-0126.0/23.0 IW-02

15.0/14.0

MW-21A2.3/2.3

MW-206S0.94/1.1

Y-0112.0/NS

Y-038.5/NS

Thomp

Coon Canyon Rd

et R

d

Inset 1

IN-03

IN-02

IN-04

IN-05

IN-03R

IN-06

27-161.2/1.1

27-420.48/ND

34-771.2/1.1

27-480.65/ND

27-491.9/1.8

34-63ND/ND

27-431.6/1.4

C2

CA-M4.2/4

MW-28B11.0/9.5

MW-38A1.7/2.0

MW-45A3.0/2.7MW-45B1.3/1.4

MW-540.93/1.1

MW-580.79/ND

MW-591.6/1.9

MW-66A3.7/3.5

MW-75D1 2/1 1

MW-76D0.86/ND

MW-76S4.1/3.9

1.1/1.3

MW-10926.0/24.0

MW-121D3.8/4.0

MW-121S2.1/2.0

MW-122DND/ND

MW 148S2.1/2.1

MW-153S5.2/5.4

CA-

CA-M45.0/

CA1.7

CA-MND/N

MW-168D0.32/ND

MW-168S1.2/1.4

MW-169D0.2/ND

MW-169S11.9/2.2

MW-169S23.1/3.3

MW-44B2.0/2.0

MW-18329.0/NS

MW-38B31.0/NS

MW-182D21.0/NS

MW-182S11.0/NS

MW-18329.0/NS

MW 158SR

MW-64B1.0/1.2

Hin

kley

Rd

Inset 2

PG&E Interpreted Plume Outlines

1. An evaluation of available hydrogeologic and groundwater quality data for the Western Area was included in the January 14, 2013, document titled Conceptual Site Model for Groundwater Flow and the Occurrence of Chromium in Groundwater of the Western Area Report (CH2MHILL and Stantec, 2013). The findings of the January 14 report indicate that groundwater in the Western Area contains naturally occurring chromium. 2. PG&E does not believe chromium concentrations north of the contiguous plume can be adequately evaluated with the information available at this time. Natural chromium levels present in the North Hinkley Valley will be further evaluated in the upcoming background study to be conducted by the United States Geological Survey.3. Some monitoring wells currently used for contouring produce very little water or purge dry during sampling. Chromium concentrations from these locations, such as MW-154S1 and MW-193S3, may not be representative of the dominant groundwater flow or PG&E's impact to local groundwater. 4. PG&E believes the chromium concentrations in the MW-196 well cluster reflect local groundwater conditions and are not related to the chromium plume. A discussion regarding these results was resented in the January 30, 2015 document titled Evaluation of Fourth Quarter 2014 Chromium Results for the MW-196 Monitoring Well Cluster, and the April 30, 2015 document titled Evaluation of First Quarter 2015 Chromium Results for the MW-196 Monitoring Well Cluster.

General PG&E Comment to Figure 5-5

IN-03

IN-01

IN-02

IN-04

IN-05

IN-03R

IN-06

02-02A0.32/ND

02-071.2/1.2

02-230.68/ND

15-051.4/1.4

15-060.83/ND15-08

1.5/1.6

27-161.2/1.1

27-261.7/1.6

27-420.48/ND

28-251.9/1.8

BGS-460.71/ND

30E-012.1/1.6

34-121.9/1.8

BGS-48ND/ND

34-771.2/1.1

36-261.6/1.5

BGS-160.6/ND

BGS-251.6/1.6

BGS-270.15/1.2

BGS-472.1/2.1

28-201.3/1.2

36-411.8/1.6

01-01A0.5/ND

02-13ND/ND

03-172.2/2.0

15-132.4/2.4

22-39ND/ND

22-80ND/ND

22-811.1/1.1

22-820.13/ND

27-480.65/ND

27-491.9/1.8

28-361.2/2.3

28-401.2/1.1

34-22ND/ND

BGS-140.25/ND

06-140.16/ND

06-150.38/ND

06-160.26/ND

22-1032.3/2.1

31E-071.4/1.2

06-200.3/ND

25-140.97/ND

03-141.5/1.9

03-191.8/1.6

30E-121.5/1.5

34-500.75/ND

34-15ND/ND

34-63ND/ND

28-510.12/ND

33-280.82/ND

33-300.58/ND

27-431.6/1.4

33-090.42/ND

33-100.68/ND

22-108ND/ND

22-933.3/3.7

28-373.3/3.1

28-522.4/2.7

23-303.3/2.8

28-663.1/3.1

28-383.3/3.1

21-020.56/ND

21-03ND/ND

34-59ND/ND

02-02B1.1/ND

28-213.8/3.5

34-38ND/ND

22-732.1/2.5

36-430.44/ND

22-621.3/1.2

23-240.59/ND

36-311.4/1.4

25-162.6/2.3

34-13ND/ND

34-24ND/ND

34-60ND/ND

34-73ND/ND

34-741.3/1.5

34-58ND/ND

22-442.0/1.8

22-650.32/ND

34-47ND/ND

22-302.3/2.2

22-751.8/1.7

27-380.065/ND

27-390.093/ND

27-401.8/1.5

28-16ND/ND

28-620.55/ND

MW-208SNS

EX-450.49/NS

EX-4718.0/NS

EX-4823.0/NS

EX-49ND/NS

EX-3720.0/NS EX-01

9.2/8.3

EX-17ND/ND

EX-100.98/1.0

EX-159.9/8.6

EX-166.3/5.3

EX-2011.0/8.9

X-112.2/NS

X-1613.0/NS

C-014.0/3.4

C-033.2/2.6

C-045.3/4.6

CA-MW-310S3.9/3.7

CA-MW-312D29.0/27.0

CA-MW-315D83.0/79.0

CA-MW-317S4.0/3.9

CA-MW-405D85.0/78.0CA-MW-406ND/ND

CA-MW-411S20.0/18.0

CA-MW-412D24.0/24.0

CA-MW-501S4.2/4.6

CA-MW-506D9.4/8.3

CA-MW-508D14.0/12.0

CA-MW-508S3.3/3.2

CA-MW-510D10.0/9.9

CA-MW-510S4.3/4.3

DW-021.7/1.4

DW-031.6/1.8

G-5R2.4/2.2

MW-0362.0/57.0

MW-050.66/ND

MW-067.2/6.2

MW-104D0.16/ND

MW-104S23.2/2.9

MW-106D0.072/ND

MW-106S3.1/2.8

MW-1338.0/34.0

MW-165.8/5.1

MW-17140/120

MW-21B127.0/27.0

MW-23B46.0/42.0

MW-28B11.0/9.5

MW-293.1/2.9

MW-30B13.9/3.6

MW-30B28.6/7.7

MW-312.9/2.8

MW-32B16.1/5.8

MW-32B29.0/8.7MW-32S2.9/4.1

MW-38A1.7/2.0

MW-41S12.0/11.0

MW-42B141.0/38.0MW-42B252.0/50.0

MW-433.4/3.4

MW-45A3.0/2.7MW-45B1.3/1.4

MW-460.58/ND

MW-472.3/2.5

MW-49A4.1/3.6

MW-49S4.0/3.8

MW-50A3.3/3.0

MW-50S15.0/15.0

MW-540.93/1.1

MW-55A0.64/NDMW-55B0.44/ND

MW-55S2.8/2.5

MW-564.9/4.7

MW-572.4/2.3

MW-580.79/ND

MW-591.6/1.9

MW-62A2.3/2.1

MW-631.2/1.5

MW-66A3.7/3.5

MW-67A0.77/2.2

MW-68D10.0/10.0

MW-68S1.6/1.9MW-69D

0.85/ND

MW-69S1.7/2.1

MW-70D2.1/2.0

MW-70S1.7/1.5

MW-71D2.2/2.4

MW-71S1.3/1.3

MW-72DND/ND

MW-72S4.8/4.6

MW-73D0.89/1.4

MW-73S0.98/1.1

MW-74D2.3/2.1

MW-75D1.2/1.1

MW-76D0.86/ND

MW-76S4.1/3.9

MW-77D1.3/2.1

MW-77S0.95/1.3

MW-78D1.7/1.7

MW-78S1.3/1.3

MW-79DND/ND

MW-79S5.8/5.6

MW-80D1.4/1.5

MW-80S2.5/2.7

MW-81S1.9/2.3

MW-82S1.1/1.3

MW-83D0.79/ND

MW-83S2.2/2.5

MW-84D0.21/ND

MW-84S2.0/1.8

MW-85DND/ND

MW-85S1.8/1.7

MW-86D1.5/1.4

MW-87D3.2/3.1

MW-87S3.1/3.8

MW-88D0.58/ND

MW-88S6.1/5.8

MW-89D0.71/ND

MW-89S3.3/3.2

MW-94D1.5/1.6

MW-94S7.3/6.9

MW-95D0.57/ND

MW-95S8.2/7.5

MW-96D0.07/ND

MW-96S1.7/1.6

MW-97D1.5/1.8

MW-97S5.1/5.1

PT2-MW-10370/NS

SA-MW-05D3600/3700

SA-MW-16S360/350

SA-MW-17S170/160

SA-MW-18D110/96.0

SA-MW-20D550/520

SC-MW-01D1.2/1.2

SC-MW-01S0.62/ND

SC-MW-02D200/180

SC-MW-02S0.97/ND

SC-MW-03D320/320

SC-MW-03S1.1/1.3

SC-MW-04D3.5/3.3

SC-MW-04S0.76/ND

SC-MW-05D1.2/1.4

SC-MW-05S0.86/ND

SC-MW-06D1.1/1.3

SC-MW-06S0.87/1.0

SC-MW-07D1.3/1.3

SC-MW-07S1.6/1.5

SC-MW-08D1.6/1.6

SC-MW-08S2.0/2.0

SC-MW-09S1.7/1.6

SC-MW-10S1.4/1.5

SC-MW-11DND/ND

SC-MW-12S390/380

SC-MW-13S130/120

SC-MW-14D0.74/ND

SC-MW-14S0.84/ND

SC-MW-16D1.3/1.4

SC-MW-16S0.79/ND

SC-MW-21S430/430

MW-101D2.7/2.6

MW-107D1.9/ND

MW-107S2.3/2.4

CA-MW-102SND/NS

CA-MW-201ND/NS

CA-MW-202ND/NS

MW-102D2.7/2.7

MW-102S1.6/1.7

MW-103D1.6/1.7

MW-103S0.071/ND

C-028.7/7.6

MW-01850/880

MW-105D0.24/ND

MW-105S2.8/2.8

MW-108D38.0/35.0

MW-108S42.0/38.0

MW-10926.0/24.0

MW-110D1.6/1.8

MW-110S4.3/4.7

MW-111D0.34/ND

MW-111S12.7/2.7MW-111S22.6/2.3

MW-112D2.7/2.5

MW-112S3.3/3.2

MW-113DND/ND

MW-113S13.2/3.8

MW-113S23.0/2.8

MW-114D10.12/NDMW-114D2ND/ND

MW-114S0.14/ND

MW-115D3.6/3.7

MW-115S2.1/2.3

MW-116D11.8/1.8

MW-116D21.3/1.3

MW-117D0.32/ND

MW-117S10.64/ND

MW-117S21.1/1.3

MW-119D1.6/1.8

MW-119S2.5/2.5

MW-36150/140

MW-3922.0/20.0

MW-57D2.7/2.6

PMW-031900/1900

SA-MW-04S260/240

MW-104S13.7/3.3

MW-116S1.3/1.5

MW-118S2.4/2.4

MW-121D3.8/4.0

MW-121S2.1/2.0

MW-122DND/ND

MW-123S12.0/1.9

MW-123S22.0/2.0

MW-124D2.4/2.2

MW-124S12.6/2.5

MW-124S20.48/ND

MW-125S12.4/2.0MW-125S21.6/1.4

MW-126S12.6/2.3

MW-126S21.4/1.5

MW-127S12.3/2.4MW-127S21.4/1.3

MW-128S23.7/3.7MW-128S31.9/2.0

MW-129S0.86/1.1

SA-MW-27D1.9/1.9

SA-MW-27S0.45/ND

MW-143D12.2/2.1

MW-144D10.56/NDMW-144D20.53/ND

MW-146D11.5/1.5MW-146D22.4/2.3

MW-146S1.1/1.0

MW-143D21.6/1.7

MW-144S1.1/1.3

MW-145D12.7/2.6MW-145D2ND/ND

MW-145S3.3/3.2

MW-147S2.5/2.5

MW-148S2.1/2.1

SA-SM-01S730/NS

MW-143S2.9/3.4

SA-MW-01S330/350

MW-14S29.0/26.0

MW-147D1.8/2.6

CA-MW-108S94.0/NS

MW-138S24.8/4.5MW-139S1

5.2/4.8

MW-139S21.8/1.8

MW-142S15.2/5.3

MW-142S22.9/3.0

MW-142S32.9/2.8

MW-149S1.6/1.4

MW-14A3.6/3.2

MW-150S10.72/NDMW-150S20.066/ND

MW-151D11.5/1.6

MW-151D22.6/3.1

MW-151S2.2/2.8

MW-152D11.3/1.3MW-152D21.5/1.7

MW-152S2.8/3.1MW-153S

5.2/5.4

SA-MW-26D0.94/1.0

SA-MW-26S330/330

FW-011.1/1.1

CA-MW-302D120/110

CA-MW-302SND/ND

MW-155DND/ND

MW-155S0.23/ND

MW-140S24.2/3.9

MW-156S0.99/1.5

MW-157S2.1/2.1

MW-140S14.6/4.1

MW-140S33.6/3.3

BW-01D4.0/3.4

BW-01S3.2/2.7

DW-012.6/2.9

EX-038.4/7.2

EX-321.4/1.3

MW-091.8/NS

MW-12B8.7/NS

MW-1851.0/NS

MW-50B2.6/2.5

MW-86S4.8/5.0

EX-21ND/ND

CA-MW-402S45.0/44.0

CA-MW-404S35.0/33.0

EX-2910.0/8.9

EX-3039.0/38.0

EX-315.2/4.6

EX-334.7/3.9

SC-MW-38D82.0/78.0

CA-MW-4011.7/1.8

SA-SM-05SND/NS

CA-MW-204SND/NS

CA-MW-3016.7/6.3

CA-MW-402DND/ND

CA-MW-403S1.2/1.5

MW-159S6.7/6.1

MW-160D4.4/4.5

MW-163S10.0/9.1

MW-164S2.4/2.5

MW-165S1.7/1.7

MW-159D6.1/5.7

MW-163DND/ND

MW-164D0.11/ND

MW-165D1.2/1.2

MW-167DND/ND

MW-167S1ND/NDMW-167S2ND/ND

MW-168D0.32/ND

MW-168S1.2/1.4

MW-169D0.2/ND

MW-169S11.9/2.2

MW-169S23.1/3.3

MW-170S2.0/2.1

CA-MW-102DND/NS

CA-MW-104D0.45/NS

CA-MW-106DND/NSCA-MW-107D22.0/NS

CA-MW-204D26.0/NS

CA-MW-404DND/NS

MW-11AND/NSMW-11B1200/1100

SA-MW-06S440/430

SA-MW-07D530/NS

SA-MW-09S280/NS

SA-MW-10D2100/2200

SA-MW-11D85.0/NS

SA-MW-15D99.0/NS

SA-MW-25D0.91/1.1

SA-MW-25S1.1/1.2

SA-SM-02S1800/NS

SA-SM-07SND/NS

SA-SM-08D190/180

SA-SM-10D38.0/NS

SA-SM-10SND/NS

SA-SM-11D92.0/82.0

SC-MW-15D1.1/1.1

SC-MW-15S0.84/1.1

SC-MW-26D1000/NS

SA-MW-02DND/ND

SA-MW-03SND/ND

SA-MW-09DND/NS

MW-171D2ND/ND

MW-171S2.6/2.6

MW-172S12.9/3.2

MW-173D0.87/ND

MW-173S13.2/3.2MW-173S22.6/2.6

MW-175D2.9/2.7

MW-175S13.4/3.1MW-175S23.3/3.0

MW-176S1.2/1.4

SA-MW-11S350/NS

MW-172S20.59/ND

MW-171D10.31/ND

EX-044.6/3.8

EX-352.2/1.6

MW-03A0.64/NS

MW-128S17.2/7.5

MW-44B2.0/2.0

EX-091.1/ND

SC-MW-38S2.1/NS

EX-053.2/2.9

MW-192S3.9/3.7

MW-177S0.76/NS

MW-178S210/220

MW-179S0.55/NS

MW-17D0.4/NS

MW-181S0.81/NS

MW-183S29.0/NS

MW-371.1/1.1

MW-38B31.0/NS

MW-39D25.0/NS

MW-67B0.73/1.3

MW-192D4.4/4.3

MW-177D1.7/NS

MW-178D210/NS

MW-179D29.0/NS

MW-181D1.2/NS

MW-182D21.0/NS

MW-182S11.0/NS

MW-183D29.0/NS

MW-187S12.4/2.6

MW-190S12.1/3.1

MW-141D0.92/ND

MW-141S13.5/3.5MW-141S24.2/4.0

MW-187D13.0/3.2

MW-187D22.1/2.4

MW-189D10.53/ND

MW-189D20.46/ND

MW-189D30.78/ND

MW-190D12.8/3.1MW-190D22.4/2.6

MW-191D11.8/1.7MW-191D21.5/1.5MW-191D32.0/1.9

MW-199D12.1/2.4

MW-199D20.69/ND

G-1R1.6/1.3

G-2R3.9/3.6

MW-199S12.4/2.6

0.37/ND

MW-201D0.42/1.3

MW-201S2.1/2.2

MW-202D1.6/1.9

MW-202S2.0/2.0

MW-203D7.2/6.9

MW-203S2.8/2.7

MW-204D0.67/ND

MW-204S13.4/3.1MW-204S24.1/3.5

MW-180RD110/NS

MW-180RS100/NS

EX-222.8/2.9

MW-20540/530

MW-21BND/ND

IW-0126.0/23.0 IW-02

15.0/14.0

MW-21A2.3/2.3

MW-206S0.94/1.1

EX-361.8/1.7

EX-0220.0/17.0

EX-232.9/NS

EX-245.9/NS

EX-251.8/NS

EX-2623.0/NS

EX-279.8/NS

EX-287.0/NS

EX-3422.0/NS

MW-08ND/ND

MW-12AND/ND

MW-158SR1.1/1.7

Y-0112.0/NS

Y-038.5/NS

IW-035.0/4.9

MW-0433.0/29.0

MW-071.7/1.4

MW-14B20.0/18.0

MW-151800/2100

MW-22B26.0/24.0

MW-27A11.0/9.2MW-27B6.6/5.8

MW-33A2.0/1.8MW-33B1.8/1.7

MW-350.82/ND

MW-41A2.9/2.8MW-41B2.7/2.5

MW-49B2.0/1.9

MW-521.6/1.6

MW-531.0/1.1

MW-64B1.0/1.2

MW-1024.0/22.0

Approximate 10-μg/L outline of Cr(VI) or Cr(T) concentrations in the Upper Aquifer, First Quarter 2015.

Approximate 50-μg/L outline of Cr(VI) or Cr(T) concentrations in the Upper Aquifer, First Quarter 2015.

Approximate outline of Cr(VI) or Cr(T) in the Upper Aquifer exceeding 3.1 and 3.2 μg/L, respectively, First Quarter 2015.

Approximate 1000-μg/L outlineof Cr(VI) or Cr(T) concentrations in the Upper Aquifer, First Quarter 2015.

?

?

?

Tindall Rd

Alcudia Rd

Front ier Rd

Hop

e S

t

Bla

nca

Rd

Park Ave

Acacia St

Syc

amor

e S

t

Hid

den

Riv

er R

d

Indi

an W

ells

Rd

Locu

stR

d

Red

Roc

k R

d

Hill

view

Rd

ManacorRd

Granada Rd

Willow Springs Rd

Fai

rvie

w R

d

Kinski Rd

Dix

ie R

d

Pue

blo

Rd

Ser

ra R

d

Pet

ra R

d

Sonoma St

Thompson Rd

Flow

erR

d

Acacia St

Sal inas Rd

Ser

ra R

d

Dix

ie R

d

Highcrest Rd

Mou

ntai

n V

iew

Rd

Coon

Canyon

Rd

Alcudia Rd

Community Blvd

Santa Fe Ave

Valle

y W

ells

Rd

Coon Canyon Rd

Lenwood Rd

Lenw

ood

Rd

Mountain General Rd

Hin

kley

Rd

Lenw

ood

Rd

Lenw

ood

Rd

Riv

ervi

ew R

d

Orc

har

58

Carson Rd

Hin

kley

Rd

Sum

mer

set

Rd

Aquarius Rd

SEE FOOTNOTE 2

SEEFOOTNOTE 3

SEEFOOTNOTE 3

Inset 1

Inset 2

FIGURE 5-5CHROMIUM RESULTS FOR FIRSTQUARTER 2015 GROUNDWATER MONITORING AND DOMESTIC WELL SAMPLING AND COMPLIANCEMAXIMUM PLUME OUTLINE IN UPPER AQUIFERFIRST QUARTER 2015 GROUNDWATER MONITORING REPORT AND DOMESTIC WELL RESULTSSITE-WIDE GROUNDWATER MONITORING PROGRAMPACIFIC GAS AND ELECTRIC COMPANY HINKLEY COMPRESSOR STATIONHINKLEY, CALIFORNIA

BAO R:\PGEHINKLEY20000353\MAPFILES\2015\GMP\Q1\FIG5-5_PLUMEMAP_UA_COMPLIANCE_INSETS.MXD GMOON 4/28/2015 7:06:59 AM

LEGEND:Groundwater monitoring wellAgricultural supply wellDomestic supply wellOther supply well Groundwater extraction well (active)Multiuse test well, or inactive extraction/injection wellFreshwater injection wellNew groundw ater m onitoring w ellfirst sam pled in First Quarter 2015PG&E-owned propertyPG&E Compressor StationCounty parcelsTransmission linesApproximate limit of saturated alluvium upper aquiferApproximate location of Lockhart Fault; fault trace is inferred, and there is no surface expression (Stamos et al., 2001)Bedrock exposed at ground surface

NOTES:1. Chromium results are shown for site-wide Groundwater Monitoring Program and domestic wells sampled in the First Quarter (January through March) 2015 monitoring period. For wells sampled multiple times during the reporting period, the most recent results are shown.

2. The concentration contours are based on First Quarter 2015 chromium results for the groundwater monitoring and extraction wells that are completed in the shallow zone and deep zone of the Upper Aquifer as noted on Figures 5-1 and 5-2. Results for domestic wells (brown-colored labels) were not used for chromium plume contouring except for those located north of Grasshopper Road, pursuant to the Lahonton Regional Water Quality Control Board's Letter Conditional Acceptance of Northern Areas Investigation Proposal dated February 26, 2014

3. Pursuant to the Lahontan Regional Water Quality Control Board’s letter Review of Chromium Plume Maps, Third Quarter 2013 Groundwater Monitoring Report and Agreement with Northern Investigation Concept dated December 12, 2013, groundwater monitoring wells are not used for chromium contouring if they are located in the areas southwest of the Lockhart Fault and on or east of Dixie Road.

4. Chromium plume contouring for concentrations of 10, 50 and 1000 ug/L are completed using the more robust dataset presented in the April 15, 2015 First Quarter 2015 Monitoring Report for the In Situ Reactive Zone and Northwest Freshwater Injection Projects and represent a composite of the shallow and deep zone contours presented therein. Select wells from that program are shown here for reference.

0 1,000 2,000

Feet

Groundwater Cr(VI) concentrations in monitoring wells:

μg/LCr(VI)Cr(T)IRZNDNS

Well IDCr(VI)/Cr(T) concentrations in μg/L; maximum of primary and duplicate samples during First Quarter 2015 sampling.

MW-77S0.95/1.3

More than 1,000 μg/L

100 to 1,000 μg/L

50 to 100 μg/L

10 to 50 μg/L

3.1 to 10 μg/L

Less than 3.1 μg/L or ND

micrograms per literhexavalent chromiumtotal dissolved chromiumIn Situ Reactive Zonenot detectednot sampled

ABBREVIATIONS: