May 2012 HRS DOCUMENTATION RECORD

— REVIEW COVER SHEET

Name of Site: SOUTHERN AVENUE INDUSTRIAL AREA

Contact Person: Karen Jurist, EPA Region 9 (415) 972

- 3219

Site Investigation: Karen Jurist, EPA Region 9 (415) 972

- 3219

Documentation Record: Amanda K.C. Reilly, Weston Solutions, Inc. (541) 593

- 3800

Pathways, Components, or Threats Not Scored

Surface Water Pathway

The surface water pathway was not scored because there are no surface water intakes, fisheries, or sensitive environments associated with the Los Angeles River downstream of the site. The Los Angeles River is located approximately 650 feet east of the sit e and empties into San Pedro Bay approximately 13 miles downstream of the site (Ref. 2 1 , Plate 1; Ref. 23). The Los Angeles River is highly modified, having been lined with concrete along a majority of its length by the U.S. Army Corps of Engineers in the 1950s. Flows are dominated by urban runoff and tertiary

treated effluent from several municipal wastewater treatment plants ( Ref. 15, p . 1, 3).

Soil Exposure Pathway

The soil exposure pathway was not scored because there are currently no known residen t individuals, sensitive environments, or resources on or within 200 feet of sources at the site. In addition, the majority of the properties are covered in pavement and/or buildings. The Seam Master business is currently operating and workers are presen t onsite (Ref. 24). However, scoring the soil exposure pathway does not affect the listing decision.

Air Migration Pathway

The air pathway was not scored because there is no documented observed release to the atmosphere, and scoring the potential to rel ease to air would not likely contribute significantly to

the overall site score.May 2012 1 HRS DOCUMENTATION RECORD

Name of Site: SOUTHERN AVENUE INDUSTRIAL AREA

EPA ID#: CAN000905902

EPA Region: 9

Date Prepared: September 2011

Street Address of Site*: 5211 Southern Avenue

City, County and State: South Gate, Los Angeles County, California 90280

Topographic Map: South Gate, California USGS 7.5

- Minute Quadrangle (Ref. 3)

Latitude : 33 o 56’ 46.24” North Longitude: 118 o 10’ 36.92” West ( Ref. 23 )

Latitude/Longitude Reference Point: The latitude and longitude were measured from sampling location SM

- 7, a contaminated soil location (Figure A

- 3; Ref. 3; Ref. 23 )

.

SCORES

Air Pathway = Not scored

Ground Water Pathway = 100.00

Soil Exposure Pathway = Not scored

Surface Water Pathway = Not scored

HRS SITE SCORE = 50.00

*The street address es, coordinates, and contaminant locations presented in this HRS documentation record identify the general area where the site is located. They represent one or more locations EPA considers to be part of the site based on the screening information EPA used t o evaluate the site for NPL listing. EPA lists national priorities among the known "releases or threatened releases" of hazardous substances; thus, the focus is on the release, not precisely delineated boundaries. A site is defined as where a hazardous s ubstance has been "deposited, stored, placed, or otherwise come to be located." Generally, HRS scoring and the subsequent listing of a release merely represent the initial determination that a certain area may need to be addressed under CERCLA. According ly, EPA contemplates that the preliminary description of facility boundaries at the time of scoring will be refined as more information is developed as to where the contamination has come to be located.May 2012 2 HAZARD RANKING SYSTEM

SUMMARY SCORESHEETS

SITE NAME: SOUTHERN AVENUE INDUSTRIAL AREA

CITY/COUNTY/STATE: South Gate, Los Angeles County, California

EPA ID #: CAN000905902

EVALUATOR: Amanda K. C. Reilly DATE: Ma y 2012

S S 2

Ground Water Migration Pathway Score (S gw ) 100.00 10,000

Surface Water Migration Pathway Score (S

sw ) Not scored Not scored

Soil Exposure Pathway Score (S

s ) Not scored Not scored

Air Migration Pathway Score (S

a ) Not scored Not scored

S gw 2 +S
sw 2 + S

s 2 + S

a 2 XXXXXXX 10,000

(S gw 2 +S
sw 2 + S

s 2 + S

a 2 ) / 4 XXXXXXX 2,500

SQRT ( (S gw 2 +S
sw 2 + S

s 2 + S

a 2 ) / 4 ) XXXXXXX 50.00

SQRT = square rootSeptember 2011 3 TABLE 3

- 1: GROUND WATER MIGRATION PATHWAY SCORESHEET

Likelihood of Release to an Aquifer Maximum Value Value Assigned

1. Observed Release 550 550

2. Potential to Release

2a. Containment 10

2b. Net Precipitation 10

2c. Depth to Aquifer 5

2d. Travel Time 35

2e. Potential to Release [lines 2a x (2b + 2c + 2d)] 500

3. Likelihood of Release (higher of lines 1 and 2e) 550 550

Waste Characteristics

4. Toxicity/Mobility a 10,000

5. Hazardous Waste Quantity a 10

6. Waste Characteristics 100 1 8

Targets

7. Nearest Well 50 18

8. Population

8a. Level I Concentrations b 0

8b. Level II Concentrations b 0

8c. Potential Contamination b 1,504

8d. Population (lines 8a + 8b + 8c) b 1,504

9. Resources 5 0

10. Wellhead Protection Area 20 0

11. Targets (lines 7 + 8d + 9 + 10) b 1,522

GROUND WATER MIGRATION SCORE FOR AN AQUIFER

12. Aquifer Score [(lines 3 x 6 x 11)/82,500] c 100 100

GROUND WATER MIGRATION PATHWAY SCORE

13. Pathway Score (S gw ), (highest value from line 12 for

all aquifers evaluated) c 100 100

a Maximum value applies to waste characteristics category.

b Maximum value not applicable.

c Do not round to nearest integer.September 2011 4

Reference

Number Description of the Reference

1 Hazard Ranking System (HRS); Final Rule, 14 December 1990, Vol. 55, No.

241. 3 p (excerpts) (A complete copy of the HRS Final Rule is also available

at http://www.epa.gov/superfund/sites/npl/hrsres/index.htm ).

2 U.S. Environmental Protection Agency (EPA), Superfund Chemic al Data Matrix (SCDM ) Methodology, January 2004. 49 p. (excerpts) (A complete copy of the SCDM is available at available at http://www.epa.gov/superfund/sites/npl/hrsres/tools/sc dm.htm )

3 U.S. Department of the Interior, U.S. Geological Survey, South Gate

Quadrangle , California

- Los Angeles County 7.5 Minute series Topographical Map, Photorevised 1981. 1 p.

4 Weston Solutions, Inc., Preliminary Assessment/Site Inspection Report,

Seam Master Industries, South Gate, California, May 8, 2003. 787 p

.

5 U.S. Environmental Protection Agency, Envirofacts Warehouse CERCLIS query results for the Seam Master Industries site (CAN000905902)

, http://www.epa.gov/enviro/html/cerclis/cerclis_query.html

, accessed November 2, 2010 . 2 p.

6 Los Angeles County Assessor, Detailed Parcel Information, Assessor ID No.:

6222

- 003

- 010, http://maps.assessor.lacounty.gov , accessed November 2, 2010. 2 p.

7 Los Angeles County Assessor, Parcel Map, Assessor ID No.: 6222

- 003

- 010, http://maps.assessor.lacounty.gov , 2003, accessed November 2, 2010. 1 p.

8 County of Los Angeles, Department of Health Services, Hazardous Waste Control Program, Inspection, Seam Master Industries, January 18, 1985. 2 p.

9 County of Los Angeles, Department of Health Services, Hazardous Waste

Control Program, Inspection, Seam Master Industries, April 18, 1986. 1 p.

10 County of Los Angeles, Department of Health Services, Order to Company,

Seam Master Industries, April 18, 1986. 1 p.

11 Weston Sol utions, Inc., Sampling and Analysis Plan, Seam Master Industries,

September 2002. 68 p.

12 U.S. Environmental Protection Agency (EPA), Superfund Chemical Data

Matrix (SCDM) Interim Revised Values, October 23, 2006. 1 p. (A complete copy of the SCDM is available at http:// www.epa.gov/superfund/sites/npl/hrsres/tools/scdm.htm )September 2011 5

13 Rice, Anitra B. and Reilly, Amanda K.C., Weston Solutions, Inc., Telephone

conversation with Ron Hernandez, City of South Gate, recorded on contact report, January 4

, June 22, 2011 and August 22, 2 011 . 2 p.

14 Jurist, Karen, U.S. Environmental Protection Agency Region 9, Photographic

Documentation and Observations Report, Seam Master Industries, February

22 , 2011. 6 p.

15 Mullin, Mike, “Splash” Stormwater Program Newsletter, City of Los

Angeles, Los Angeles River Characterization Study Underway, Fall 2000. 4

p.

16 U.S. Environmental Protection Agency, Envirofacts Warehouse CERCLIS

query results for the Cooper Drum Co. site (CAD055753370)

, http://www.epa.gov/enviro/html/cerclis/cerclis_query.html , accessed March 28, 2011

. 3 p.

17 Innovative Technical Solutions, Inc., Cooper Drum Company Superfund Site

Remedial Design Technical Memorandum for Field Sampling Results,

Addendum No. 4, February 26, 2010. 451 pages.

18 Rice, Anitra B. and Reilly, Amanda K.C., Weston Solutions, Inc., Telephone

conversation with Martin Gonzalez, Walnut Park Mutual Water Company, recorded on contact, October 29, 2010 June 30, 2011 , and August 18, 2011 . 1

p.

19 Rice, Anitra B. and Reilly, Amanda K.C., Weston Solutions, Inc., Telephone

c onversation with Bob Rohlf , Maywood Mutual Water Company #3, recorded on contact report, December 2, 2010

, and August 24, 2011. 1 p.

20 California Department of Water Resources, California’s Groundwater

Bulletin 118, Coastal Plain of Los Angeles Groundwater Basin, Central Subbasin, February 27, 2004. 6 p. (excerpts)

21 State of California, Department of Water Resources, Southern District,

excerpts of Bulletin No. 104, Planned Utilization of the Ground Water Basins of the Coastal Plain of Los Angeles County, Appendix A, Ground Water Geology, June 1961. 207 p. (including Plates 1, 2, 3A, 3B , 4, 5, 6A, 6B, 6E and Table 1)

. (excerpts).

22 URS Group, Inc., Copper Drum Company Remedial Investigation Feasibility

Study Report Volume 1, May 15, 2002. 1,087 p.

23 Google Earth, 33 o 56’ 46.24” N, 118 o 10’ 36.92” W, California,

http://earth.google.com/, July 6, 2011 . 1 p.

24 Seam Master, www.seammaster.com , accessed June 30, 2011. 2 p.September 2011 6

25 Jurist, Karen, U.S. EPA Region IX, Telephone Conversation with Jose

Molina, City of Lynwood Public Works, , May 25, 2011. 1 p.

26 KAP Technologies, Inc., SDG Narrative, Case No: 38516, SDG No: Y4W26,

June 4, 2009. 1,546 p.

27 KAP Technologies, Inc., SDG Narrative, Case No: 38516, SDG No: Y4W42

,

J une 2 , 2009. 1,53 6 p.

28 Reilly, Amanda K.C., Weston Solutions, Inc., Memorandum Re: Sample

Quantitation Limits, June 29 , 2011

. 5 p.

29 Geology Dictionary, http://geology.com/dictionary/glossary

- a.shtml

,

accessed June 30, 2011. 2 p.

30 U.S. Environmental Protection Agency, Envirofacts Warehouse CERCLIS

query results for the Je rvis B. Webb Co. site (CAD008339467)

, http://www.epa.gov/enviro/html/cerclis/cerclis_query.html , accessed June 30,

2011. 1 p.

31 National Institute of Environmental Health Sciences, In Situ Bioremediation

of TCE, Superfund Research Program, Enhancing and Monitoring the Rates

of Microbial Transformation of Chlorinated Solvents in Anaerobic Groundwater, http://www.niehs.nih.gov/research/supported/srp/products/products2_s1_s2.c

fm , accessed June 30, 2011. 3 p.

32 Reilly, Amanda K.C., Weston Solutions, Inc., Memorandum Re: Reference

21 supplemental map s
, August 2 3 , 2011

. 5 p.September 2011 7 ACRONYM LIST

AST Aboveground Storage Tank bgs below ground surface

CERCLIS Comprehensive Environmental Response, Compensation, and Liability

Information System

CPT Cone Penetrometer Test

DCA Dichloroethane

DCE Dichloroethylene

DHS County of Los Angeles, Department of Health Services

DWR State of California Department of Water Resources, Southern District

EPA United States Environmental Protection Agency

HRS Hazard Ranking System ug/kg micrograms per kilogram ug/l micrograms per liter

NOV Notice of Violation

PA /SI Preliminary Assessment/Site Inspection

PCE Tetrachloroethylene or Tetrachloroethene RWQCB Regional Water Quality Control Board

Seam Master Seam Master Industries

TCA Trichloroethane

TCE Trichloroethylene or Trichloroethene

USACE United States Army Corps of Engineers

UST Underground Storage Tank

VOC Volatile Organic CompoundSeptember 2011 8

NOTES TO THE READER

1. Attachment A contains the following maps:

— Figure A

- 1: Seam Master Industries Property Location Map

— Figure A

- 2: Seam Master Industries Facility Layout Map

— Figure A

- 3: Historic Sample Location Map

— Figure A

- 4: Drinking Water Well and Radius MapMay 2012 9 SITE DESCRIPTION

In the general vicinity of the Southern Avenue Industrial Area site (formerly referred to as the Seam Master Industries site), Seam Master Industries (Seam Master) property is located at 5211 Southern Avenue, South Gate, Los Angeles County, California (Ref . 3; Ref. 4, p. 8; Ref. 5, p. 1). The property occupies approximately 3.85 acres (Ref. 6, p. 1; Ref. 7, p. 1). The Seam Master property location is presented in Figure A

- 1. The source evaluated for this HRS documentation

record includes VOC

- contaminated soil located in the southeastern portion of the property (Ref. 4, p. 12; Figure A

- 3 of the HRS documentation record). The site includes the contaminated soil source and releases of volatile organic compounds (VOCs) and associated ground water

contaminati on, which pose a hazard to people (see Section 3.1.1).

Since 1972, the Seam Master facility has been operating as a hot

- melt adhesive manufacturing company (Ref. 4, p. 38). Inspections conducted by the County of Los Angeles Department of

Health Service s (DHS) in 1985 and 1986 indicate that chlorinated hydrocarbons were used on the property (Ref. 8, p. 1, Ref. 9, p. 1). During the 1986 inspection, DHS observed one drum of retrograde trichloroethylene (TCE). A notice of violation (NOV) was issued at thi s time due to the illegal storage of retrograde TCE and ordered to properly dispose of the waste (Ref. 9, p. 1; Ref. 10, p. 1).

In 2002, a Preliminary Assessment/Site Inspection (PA/SI) was conducted at the Southern

Avenue Industrial Area site . Ground water beneath the Seam Master property and soils on the property were sampled as part of the investigation. Soil samples indicated that TCE and cis

- 1,2

- DCE were detected at concentrations above background concentrations (Ref. 4, p. 12). TCE was

detected at a maximum concentration of 17 ug/kg and cis

- 1,2

- DCE was detected at a maximum concentration of 7,100 ug/kg (Ref. 4, p. 434, 452). Ground water samples collected beneath the property indicated that TCE and cis

- 1,2

- DCE were present in ground water at con centrations significantly above background concentrations. Maximum concentrations of TCE and cis

- 1,2

- DCE detected were 17,000 micrograms per liter (ug/l) and 8,000 ug/l, respectively (Ref. 4, p. 13).

The Cooper Drum Company Superfund Site (EPA ID: CAD0 55753370) is located at 9316 Atlantic Avenue in South Gate, California (Ref. 16, p. 1

- 2). The 3.8 acre facility is located approximately 300 feet northwest, and hydraulically upgradient, of the Seam Master property (Ref. 17, p. 7, 8, 67, 70

- 72; Ref. 23). The Cooper Drum facility activities included drum reconditioning since the 1940s. Contaminants of concern associated with the Cooper Drum facility include TCE and cis

- 1,2

- DCE (Ref. 17, p. 7, 8). The Cooper Drum site was proposed to NPL on January 11, 20 01 and received its final listing on NPL on June 14, 2001 (Ref. 16, p. 2). This HRS documentation record is a listing of releases from the Southern Avenue site, not from Cooper Drum, that are contributing to a TCE

- and cis

- 1,2

- DCE

- contaminated ground wate r plume (see Sections 2.2 and 3.0 of this HRS documentation record).May 2012 10

Investigations conducted on the Cooper Drum site involved sampling ground water beneath and downgradient of the Seam Master property. Between September 1998 and March 2001, ground

wat er sampling was conducted as part of a Phase 2 remedial investigation of the Cooper Drum site and depth

- discrete ground water samples were collected and analyzed at the Southern

Avenue Industrial Area site (Ref. 14, p. 4; Ref. 22, p. 20). Analytical resul ts indicated that ground water beneath the Seam Master property exhibited maximum concentrations of TCE at 16,000 ug/l and cis

- 1,2

- DCE at 4,900 ug/l (Ref. 22, p. 122). In addition, in May 2009, all new and existing ground water monitoring wells were sampl ed as part of the continued investigation of the Cooper Drum site. Three of the monitoring wells samples were located on or directly down gradient of the Seam Master property (Ref. 17, p. 15, 68). Analytical results indicated that ground water directly d own gradient of the Seam Master property exhibited maximum concentrations of TCE at 46 ug/l and cis

- 1,2

- DCE at 420 ug/l (Ref. 17, p. 61, 310).

The Southern Avenue Industrial Area site is located in an urban area, in which numerous drinking water wells are located (Ref. 13; Ref. 18; Ref. 19; Ref. 25; Ref. 32, p. 2; Figures A

- 1

and A

- 4 of the HRS documentation record). Ground water contamination within the Gaspur aquifer has been identi fied beneath the Southern Avenue Industrial Area site (Ref. 4, p. 13, 14; Ref. 17, p. 43, 44, 51, 52; Ref. 22, p. 70). Eight drinking water wells screened within the Gage and Exposition aquifers are located within 4 miles of the source at the site (Ref. 1 3, p. 2; Ref. 18; Ref. 19; Ref. 21, Plate 3A; Ref. 25). These wells were evaluated for potential contamination.

Interconnection between the Semi

- perched, Gaspur, Exposition, and Gage aquifers is established

within 2 miles of the source at the site and th erefore are eligible to be scored as one interconnected aquifer (Ref. 1, Section 3.0.1.2.1; Ref. 21, Plates 3A, 6A, and 6E; Ref. 32, p. 2; Figures A

- 1 and A

- 2 of the HRS documentation record).May 2012 11

2.2 SOURCE CHARACTERIZATION

2.2.1 SOURCE IDENTIFICATION

Name of source: Contaminated soil at Seam Master Industries Number of source: 1

Source Type : Contaminated Soil

Description and Location of Source (see Figure A

- 2):

Source 1 consists of contaminated soils located on the Seam Master property located at 5211 Southern Avenue in South Gate, Los Angeles County, California ( Ref. 4, p. 8, 17; Ref. 5, p. 1; Figures A

- 1 and A

- 3 of the HRS documentation record)

.

Soils contaminated with VOCs associated with the Seam Master operations have been detected

at c oncentrations above background in soil samples collected on the property. Samples were collected during the October and November 2002 PA/SI sampling event (Ref. 4, p. 12). EPA collected soil samples at various depths from seven borings (Ref. 4, p. 12, 13 , 34).

The Seam Master property lies on Los Angeles County Assessor Parcel Number 6222

- 003

- 010 and is approximately 3.85 acres (Ref. 6, p. 1; Ref. 7, p. 1). The property consists of two enclosed buildings, one partially enclosed building or shed, a pal let manufacturing area, and a paved parking lot. In the northwest portion of the property are three concrete liners that are approximately seven feet deep and covered with chicken wire for safety purposes. Reportedly, aboveground storage tanks occupied t he liners prior to 1972. In the southeastern portion of the property is an underground storage tank that has, reportedly, not been utilized by Seam Master. In the southeastern portion section of the large enclosed building is a sump (Ref. 4, p. 34, 38). A facility layout is presented in Figure A

- 2.

During the 2002 PA/SI conducted at the Southern Avenue Industrial Area site , seven borings were drilled in order to collect soil samples. Of the seven borings, one boring was located offsite in order to obtain a background sample and six borings were located on the Seam Master property. Boring SM

- 1 was the background sample, and located offsite and north of the Seam Master property, borings SM

- 3 and SM

- 4 were located adjacent to the concrete liners in the northwest portion of the property, boring SM

- 5 was located south of the concrete liners, and borings SM

- 7, SM

- 8 and SM

- 9 were located in the southeastern portion of the property, adjacent

t o the sump (Ref. 4, p. 34). Soil samples SM

- 7

- S2 and SM

- 7

- S5 exhibited concentrations of

TCE and cis

- 1,2

- DCE significantly exceeding background concentrations (Ref. 4, p. 29). Sample locations are presented in Figure A

- 3.May 2012 12

Source Containment

Release t o ground water:

Photographs taken in February 2011 show ed that although the Seam Master property is paved, the pavement is in poor condition and contains multiple crac ks ( Ref. 14, p. 2, 3, 5). In addition, during the 2002 sampling event, there was no evidence that a liner or engineered cover were present at or beneath the ground surface (Ref. 4, p. 48). Precipitation could infiltrate the contaminated soil beneath the pavement. Therefore, a containment factor value of 10 is assigned (Ref. 1 Sections 2 .2.3 and 3.1.2.1 and Table 3

- 2).

2.2.2 HAZARDOUS SUBSTANCES ASSOCIATED WITH THE SOURCE

Between October 9 and November 5, 2002, a PA/SI was conducted at the Southern Avenue

Industrial Area site , under the direction of the EPA (Ref. 4, p. 12). Soil sampl e were collected at various depths from seven borings. All samples were analyzed for VOCs using EPA Method OLC03.2 (Ref. 4, p. 13). The data were validated by the United States Army Corps of Engineers (USACE) Quality Assurance Office (Ref. 4, p. 12, 632

- 638).

Soil samples were collected using a 5 gram disposable volumetric sampling device , and were collected in triplicate. All samples were sealed using the disposable volumetric sampler and a sealable plastic bag. Sample containers were closed as so on as they were filled, immediately custody sealed, labeled, and placed on ice for shipment to the laboratory (Ref. 11, p. 27).

Summarized below is analytical evi dence of contamination in soil samples associated with the

contaminated soil at the Southern Avenue Industrial Area site

.

Background Concentrations

Source samples were compared to the background sample collected during the respective sampling event. During the PA/SI sampling event conducted in 2002, two background samples

were collected from one location and two sampling depths, 2 feet and 5 feet bgs. Samples SM

- 1

- S2 and SM

- 1

- S5 were collected from the adjacent west property (Ref. 4, p. 34).

Sample ID Sampling Date Hazardous

Substance Concentration

(ug/kg ) CRQL

(ug/kg ) References

SM

- 1

- S2 10/29/2002 TCE 5.4 U 5.4 Ref. 4, p. 633, 641, 653 cis

- 1,2

- DCE 5.4 U 5.4

SM

- 1

- S5 10/29/2002 TCE 5.4 U 5.4 Ref. 4, p. 633, 641, 657 cis

- 1,2

- DCE 5.4 U 5.4

Notes:

CRQL: Contract Required Quantitation Limit ug/kg: micrograms per kilogramMay 2012 13

U: The analyte was analyzed for but was not detected above the level of the reported contract required quantitation limit (Ref. 4, p. 634)

TCE: Trichloroethylene

DCE: Dichloroethene

Source Samples

Between October 9 and November 5, 2002, a PA/SI was conducted at the Southern Avenue

Industrial Area site , under the direction of the EPA (Ref. 4, p. 12). A total of 14 soil samples were collected from 7 locations at various depths ranging from 2 feet to 10 feet bgs (Ref. 4, p. 34, 48). Samples SM

- 7

- S2 and SM

- 7

- S5 were collected from one location at two sampling depths, 2 feet and 5 feet bgs, and TCE and 1,2

- cis

- DCE were detected above background concentrations (Ref. 4, p. 29).

Sample ID Sampling Date Ha zardous

Substance Concentration

(ug/kg ) CRQL

(ug/kg ) References

SM

- 7

- S2 10/30/2002 TCE 7.5 6.5 Ref. 4, p. 373, 410, 424, 633 cis

- 1,2

- DCE 6,100 300

SM

- 7

- S5 10/30/2002 TCE 17 5.5 Ref. 4, p. 373, 434, 452, 633 cis

- 1,2

- DCE 7,100 260

Notes:

CRQL: Contract Required Quantitation Limit ug/kg: micrograms per kilogram

TCE: Trichloroethylene

DCE: DichloroetheneSeptember 2011 14

2.4.2 HAZARDOUS WASTE QUANTITY

Tier A: Hazardous Constituent Quantity

- Not Evaluated (NE)

The information available is not sufficient to meaningfully evaluate Tier A, hazardous constituent quantity; therefore it is not possible to adequately determine a hazardous constituent quantity for Source 1 (Ref. 1, Section 2.4.2.1.1). Scoring proceeds to the evaluation of Tier B

, Hazardous Wastestream Quantity (Ref. 1, Sections 2.4.2.1.1 and 2.4.2.1.2).

Hazardous Constituent Quantity Value: NE

Tier B: Hazardous Wastestream Quantity

- Not Evaluated (NE)

The information available is not sufficient to meaningfully evaluate Tier B, hazardous wastestream quantity; therefore it is not possible to adequately determine a hazardous wastestream quantity for Source 1 (Ref. 1, Section 2.4.2.1.2). Scoring proceeds to the evaluation of Tier C, Volume (Ref. 1, Sections 2.4.2.1.2 and 2.4.2. 1.3).

Hazardous Wastestream Quantity Value: NE

Tier C: Volume

The information available is not sufficient to meaningfully evaluate Tier C, volume; therefore it is not possible to adequately determine a volume for Source 1 (Ref. 1, Section 2.4.2.1.3). Scoring proceeds to the evaluation of Tier D, Area (Ref. 1, Sectio ns and 2.4.2.1.3 and 2.4.2.1.4).

Volume Assigned Value: 0

Tier D: Area

The area of contaminated soil is unknown, but greater than 0. Analytical results of the 2002 soil sampling effort indicate the presence of contaminated soil in the southeastern portion of the property (boring SM

- 7) ( Ref. 1, Section 2.4.2.1.4; Ref. 4, p. 17; Figure A

- 3 of the HRS documentation record).

Area Assigned Value: >0September 2011 15

Source Hazardous Waste Quantity Value

According to the Hazard Ranking System (HRS) , the highest of the values assigned to the source for hazardous constituent quantity (Tier A), hazardous wastestream quantity (Tier B), Volume (Tier C), and Area (Tier D) should be assigned as the source hazardous waste quantity value (Ref. 1, Section 2.4.2.1.5).

Tier Evalu ated Source 1 Values

A NE

B NE

C 0

D >0*

Note:

* Value selected for the source hazardous waste quantity value, according to the HRS.

NE Not Evaluated.

Source Hazardous Waste Quantity Value: >0September 2011 16 SITE SUMMARY OF SOURCE DESCRIPTIONS

Source

No. Source Hazardous

Waste Quantity

Value Containment

Ground

Water Surface

Water Gas Air

Particulate

1 >0 10 NE NE NE

TOTAL >0

Notes:

NE = Not Evaluated.May 2012 17 POSSIBLE SOURCES NOT SCORED

 Three concrete liners/former aboveground storage tanks (ASTs). The concrete liners are located in the northwest corner of the Seam Master property (Ref. 4, p. 9, 38). The liners are approximatel y 7 feet deep and covered with chicken wire for safety purposes. During

the 2002 PA/SI conducted at the Southern Avenue Industrial Area site , nothing was observed inside the concrete liners. However, the business manager stated that ASTs

were inside the liners prior to 1972, when a screw manufacturer operated on the property (Ref. 4, p. 38, 46, 47).

 White holding tanks. During the 2002 PA/SI conducted on the Southern Avenue

Industrial Area site , three aboveground white holding tanks were observed along the eastern portion of the Seam Master property. They were currently not in use (Ref. 4, p. 44). However, previous businesses may have utilized the tanks for hazardous substances.

 Underground s torage tank. The underground storage tank (UST) is located in the southeastern portion of the property (Ref. 4, p. 9, 38). As of 2002, the UST was not used for Seam Master operations and the business manager suspected that it was utilized by prior tenant s for gasoline products (Ref. 4, p. 9, 38).May 2012 18

3.0 GROUND WATER MIGRATION PATHWAY

3.0.1 GENERAL CONSIDERATIONS

The Southern Avenue Industrial Area site is located in the Central Basin Pressure Area of the

Central Basin of the Los Angeles Coastal Plain ( Ref. 20, p. 1; Ref. 21, pp. 130, 166 , Plate 2 ; Ref. 22, p. 32, 33; Ref. 32, p. 2; Figure A

- 1 of the HRS documentation record ). Ground water is

found in t he Recent Alluvium, Lakewood Formation, and San Pedro Formation ( Ref. 21, p. 188; Ref. 22, p. 33 ). Geologic materials in the unsaturated zone of the Recent Alluvium, between ground surface and the top of the Lakewood Formation are primarily composed of sa ndy silts to silty clays and have been described as correlating with the Bellflower Aquiclude (Ref. 17, p. 8,

101

- 103; Ref. 21, p. 168, 169)

. An aquiclude is defined as a subsurface rock, soil, or sediment unit that does not yield useful quantities of w ater (Ref. 29, p. 1). Interbedded within the Bellflower Aquiclude are discontinuous lenses of silty

- sands that may allow for the presence of one or more perched aquifers. The groundwater flow direction within these perched aquifers is

sensitive to litholo gic variations, groundwater extraction, and/or surface water recharge ( Ref. 17, p. 8, 10; Ref. 20, p. 1

- 3; Ref. 21, p.168)

In the South Gate area, shallow ground water occurs at a depth of approximately 45 feet bgs, with a ground water flow direction to the south or southeast. Shallow ground water in the vicinity of the Southern Avenue Industrial Area site is expected to be similar to the nearby Cooper Drum Company property, where it occurs within or is controlled by the near surface Bellflower Aquiclud e, which incorporates the S emi

- perched A quifer (Ref. 17, p. 8, 9; Ref. 22, p. 18, 19). In the vicinity of the facility , the Lakewood Formation, which immediately underlies the Recent Alluvium, consists of the Gaspur Aquifer, Exposition Aquifer, an unnamed aquiclude

, and the Gage A quifer. Ground water flow within the Gaspur Aquifer is generally to the south

beneath the Southern Avenue Industrial Area site (Ref. 17, p. 70

– 72). Although data are not adequate to document ground water flow within the Exposi tion and Gage aquifers, it is assumed that the flow direction would be generally towards the south, in the direction of the Pacific Ocean (Ref. 20, p. 2). The San Pedro Formation, which underlies the Lakewood Formation, consists of the Hollydale, Jefferso n, Lynwood, Silverado, and Sunnyside A quifers with intervening aquitards [ Ref. 21, p. 182, 183, 184 , Plate 6A (Geologic Section B

- B’) ; Figures A

- 1

and A

- 2 of the HRS documentation record ]. The main hydrogeologic features identified beneath

the Southern Av enue Industrial Area site include the Bellflower Aquiclude, the Semi

- perched

A quifer, and the Gaspur

, Exposition , and Gage Aquifers. These latter units co nstitute a shallow aquifer and two deeper aquifer s , respectively. ( Ref. 17, p. 8; Ref. 21, p. 182; Re f. 22, p. 19; Ref. 32, p. 2; Figures A

- 1 and A

- 2 of the HRS documentation record ).

It appears that the Lakewood and San Pedro formations may not be in hydraulic continuity

within 2 miles of the Southern Avenue Industrial Area site [Ref. 21, p. 166 , Plat es 3A, 6A (Geologic Section B

- B’), 6E (Geologic Section L

- L’) ; Ref. 32, p. 1

- 2 ]. In the late 1950s, the State of California Department of Water Resources, Southern District (DWR), compiled 50May 2012 19

geologic sections for the Los Angeles Coastal Plain (Ref. 21, p . 2, 3, 20)

. The geologic sections were compiled in order to complete a geologic picture of the Coastal Plain of Los Angeles County. These sections are based on electric logs and drillers’ logs from approximately 200 oil

wells and 3,500 water wells (Ref. 21, p. 20 ). Examination of DWR geologic sections B

- B’ and

L

- L’ suggests that the lowermost aquifer in the Lakewood Formation (i.e., the Gage aquifer) is separated from the uppermost aquifer in the San Pedro Formation (i.e., the Hollydale aquifer) by

a la terally continuous lower permeability layer in the vicinity of the property [Ref. 21, p. 166

, Plates 3A , 6A (Geologic Section B

- B’), 6B (Geologic Section C

- C ’)]. Interconnections between

the Semi

- perched, Gaspur, Exposition, and Gage aquifers is establish ed within 2 miles of the source at the site and therefore are eligible to be scored as one interconnected aquifer (Ref. 1, Section 3.0.1.2.1; Ref. 21, Plates 3A, 6A, and 6E; Ref. 32, p. 2; Figures A

- 1 and A

- 2 of the HRS documentation record). Since data a re not adequate to establish aquifer interconnection between

the Lakewood and San Pedro formations within 2 miles of the Southern Avenue Industrial Area

site (see preceding paragraph) and an observed release is documented to the Semi

- perched, Gaspur, Expos ition, and Gage aquifers [see Section 3.1.1 (Observed Release) of this HRS documentation record], the following hydrogeologic discussion is limited to those strata that

have been identified in the Recent Alluvium and Lakewood Formation.

- Stratum 1: Be llflower Aquiclude and Semi

- Perched Aquifer

The Bellflower Aquiclude extends from the surface to a depth of approximately 55 to 70 feet bgs and consists of sandy silts, clayey silts, an d lesser amounts of silty clay. The semi

- perched aquifer is present within the Bellflower Aquiclude. Water levels are generally found in a laterally continuous 5

- foot

- thick silty/sandy unit at approximately 35 to 40 feet bgs, which is underlain by finer materials of the Bellflower Aquiclude ( Ref . 17, p. 8; Ref. 22, p. 34, 35 ). The Bellflower Aquiclude does not restrict ground water movement between the strata composing the aquifer (Ref. 17, p. 52, 61,101

- 103, 165, 166; Ref. 21, pp. 62, 63, 72, 73, 77, 168, 169, 184, 185).

- Stratum 2: Gaspur Aquifer

The shallow aquifer is represented by the Gaspur Aquifer which underlies the Bellflower Aquiclude and extends to a depth of approximately 110 to 120 feet bgs. The Gaspur Aquifer is of fluvial origin and occurs within an ancestral Los Angeles Riv er channel. The Gaspur Aquifer consists of sandy units varying from very fine to medium and coarse and to a lesser extent finer units comprising silty sand and sandy silt. Water level in the Gaspur Aquifer is generally at a depth that corresponds to the Lower Bellflower Aquiclude, suggesting the Gaspur Aquifer is a

semi

- confined aquifer (Ref. 17, p. 8, 101

- 103; Ref. 22, p. 34)

. The horizontal flow direction in the Gaspur Aquifer is toward the south (Ref. 17, p. 9).

- Stratum 3 : Exposition AquiferMay 2012 20

The Exposition Aquifer, which underlies the Gaspur Aquifer, begins at a depth of approximately 110 to 120 feet bgs (Ref. 17, p. 8). The maximum thickness of the Exposition Aquifer is 100 feet and is reportedly related to the ancestral Los Angeles River drain age system. Materials range in size from coarse gravels to clay, with the fine deposits separating the lenticular sandy and gravelly beds. The upper coarse members of the Exposition appear to have been either eroded and backfilled by the overlying Gaspur Aquifer deposits, or some of the upper members were deposited contemporaneously with the formation of t he younger Gaspur Aquifer (Ref. 22, p. 34 ).

- Stratum 4: Unnamed Aquiclude

Based on DWR Geologic Section B

- B’, a lower permeability layer underlies th e Exposition aquifer beneath the Seam Master facility

. It extends from approximately 160 feet bgs to 200 feet bgs [ Ref. 21 , Plates 3 A, 6A (Geologic Section B

- B’); Figures A

- 1 and A

- 2 of the HRS documentation record].

- Stratum 5 : Gage Aquifer

The Gage aquifer generally consists of fine

- grained sand and silty sand in the Central Basin

Pressure Area ( Ref. 21 , p. 183, 184 ). T his aquif er underlies the unnamed aquiclude and extends from 200 feet bgs to 275 feet bgs beneath the Southern Avenue Industrial Are a site [ Ref. 21

, Plates 3A, 6A (Geologic Section B

- B’)].

- Aquifer Interconnection

Interconnection between the Semi

- Perched, Gaspur, Exposition, and Gage A quifers is

established within 2 miles of Source 1 at the property as follows (Ref. 1, Section 3.0.1.2.1) :

 Contamination has been documented in two monitoring wells (MW

- 34 and MW

- 35) located directly downgradient of the Seam Master facility (Ref. 17, p. 15, 38, 61, 68, 310, 311). Monitoring wells MW

- 34 and MW

- 35 are screened w ith in the Gaspur A quifer (Ref. 17, p. 8, 38, 51). This supports that the Bellflower Aquiclude and Semi

- perched Aquifer are interconnected to the underlying formations (i.e., Lakewood Formation) since contaminants have passed through to the lower aquifers.

 An examination of DWR Geologic Sections B

- B’ and L

- L’ indicates that the Gaspur

A quifer is in dire ct contact with the Exposition A quifer in the property vicinity (Ref . 21, Plates 3A, 6A, and 6E ; Ref. 32, p. 2; Figures A

- 1 and A

- 2 of the HRS documentation

r ecord).

 An examination of DWR Geologic Section B

- B’ ind icates that the unnamed aquiclude

b etween the Exposition and Gage A quifers is not continuous within 2 miles of the

Southern Avenue Industrial Area site . This aquiclude is shown as pinching out approximately 1,500 feet to the west of the property , resulting in a merging of the twoMay 2012 21

aquifers [ Ref. 1, Section 3.0.1.2.1; Ref. 21 , Plates 3A and 6A (Geologic Section B

- B’ ); Ref. 32, p. 2; Figures A

- 1 and A

- 2 of the HRS document ation record ].

- Aquifer Discontinuities

An examination of DWR Plate 3A indicate that the Southern Avenue Industrial Area site is located between Geologic Sections B

- B’ and C

- C’ that run generally southwest

- northeast, and between Geologic Sections K

- K’ a nd L

- L’ that run generally northwest

- southeast (Ref. 21, Plate 3A). An examination of Geologic Sections B

- B’, C

- C’, K

- K’ and L

- L’ show that there are no aquifer discontinuities between the Semi

- Perched and Gage aquifers within 4 miles of Source 1

at the S outhern Avenue Industrial Area site (Ref. 1, Section 3.0.1.2.2; Ref. 21, Plate 6A, Plate 6B, Plate 6E; Ref. 32, p. 2; Figures A

- 1 and A

- 2 of the HRS documentation record).

SUMMARY OF AQUIFER BEING EVALUATED

Aquifer

No. Aquifer Name Is Aquifer

Interconnected with Upper Aquifer within 2 miles? (Y/N/NA) Is Aquifer

Continuous

within 4

- mile TDL? (Y/N) Is Aquifer

Karst? (Y/N)

1 Semi

Perched / Gaspur/ Exposition/Gage Y Y N

Notes:

Y: Yes

N: No

NA: Not applicableMay 2012 22

3.1 LIKELIHOOD OF RELEASE

3.1.1 OBSERVED RELEASE

Aquifer Being Evaluated: Semi

- Perched / Gaspur/ Exposition/Gage

Chemical Analysis

2000 Investigation Sampling

Between September 1998 and March 2001, ground water sampling was conducted at the

Southern Avenue Industrial Area site as part of a Phase 2 remedial investigation of the Cooper Drum site. As part of the investigation, cone penetrometer test (CPT) borings were drilled on the

Southern Avenue Industrial Area site and depth

- discrete ground water samples were collected and analyzed (Ref. 14, p. 4; Ref. 22, p. 20). All samples were analyzed for VOCs by gas chromatography/mass spectrometry (GC/MS) Regional Analy tical Program/non

- Contract Laboratory Program low

- level volatile organics analysis with 25 mL purge (Ref. 22, p. 55, 63

, 849, 855 ).

Ground water sample locations are shown in Figure A

- 3 and Reference 22, page 68.

- Background Concentrations:

Background levels for site

- related VOC hazardous substances are established below based on the analytical results from ground water collected from borings CPT

- 16 and CPT

- 20. Boring CPT

16 was located northwest of the Seam Master property adjacent south to the ELG M etals building, upgradient of the Seam Master property production warehouse and raw material storage and downgradient of the Copper Drum and Jervis properties. Boring CPT

- 20 was located in the northeast portion of the Seam Master property, upgradient of t he Seam Master production warehouse and raw material storage and downgradient of ELG Metals (Ref. 22, p. 51, 68, 83).

Ground water collected from borings CPT

- 16 and CPT

- 20 are used to establish background levels for the contaminated ground water sample collected from boring CPT

- 21 listed below. Data are compared to background samples collected during the same sampling event using the same methodology. All ground water samples were collected using a drive sampler. The drive sampler is driven into undis turbed soil beneath the bottom of a borehole. When at the desired depth, the sampler is pulled back approximately one foot to expose the screen on the sampler. Depth

- discrete ground water samples are collected by lowering a bailer down the sampling

devic e, retrieving the bailer and transferring the ground water sample to the sample container (Ref. 22, p. 55). The ground water samples presented below were collected at depths between 60 and 65 feet bgs (Ref. 22, p. 122).May 2012 23

Sample ID Sample

Depth (ft bgs) Sampling

Date Hazardous

Substance Concentration

(ug/l) CR QL

(ug/l) References

CPT

- 16 60 10/10/2000 TCE 0.5 U 0.5 Ref. 22, p. 122, 415, 651, 843, 844, 855,

849 cis

- 1,2

- DCE 0.5 U 0.5

CPT

- 20 64 10/9/2000 TCE 24 0.5 Ref. 22, p. 122, 417, 649, 847, 848, 849

, 855 cis

- 1,2

- DCE 9 0.5

Notes:

CRQL: Contract Required Quantitation Limit ft bgs: feet below ground surface ug/l: micrograms per liter

U: The analyte was analyzed for but was not detected above the level of the reported sample quantitation limit

- Contaminated Samples:

The boring listed below is located downgradient of the source at the Seam Master facility. For conservative purposes, the higher concentration background levels from the October 2000 sampling event (CPT

- 20) are compared to the October 2000 contaminated sample in order to establish a release. Sample locations are presented in Figure A

- 3 and Reference 22, page 68

.

Sample ID Sample

Depth (ft bgs) Sampling

Date Hazardous

Substance Concentration

(ug/l) CRQL

(ug/l) References

CPT

- 21 63 10/9/2000 TCE 8,000 0.5 Ref. 22, p. 122, 418, 649, 849, 851, 852,

855 cis

- 1,2

- DCE 4,900 0.5

Notes:
CRQL: Contract Required Quantitation Limit ft bgs: feet below ground surface ug/l: micrograms per liter

2002 Seam Master PA/SI Ground Water Sampling

In 2002, ground water sampling was conducted as part of the PA/SI investigation on the

Southern Avenue Industrial Area site . Ground water samples were collected from one monitoring well and five borings. All samples were analyzed for VOCs usin g EPA Method OLM04.2 (Ref. 4, p. 12, 13, 14).

Ground water sample locations are shown in Figure A

- 3 and Reference 4, page 33.

- Background Concentrations:

Background levels for site

- related VOC hazardous substances are established below based on the analytical results from ground water collected from boring SM

- 1 and monitoring well MW

- 14. Boring SM

- 1 was located northwest of the Seam Master property on the CEE Sportsware property, upgradient of the Seam Master prop erty and downgradient of the Cooper Drum andSeptember 2011 24

Jervis properties. Monitoring well MW

- 14 is located north of the Seam Master property on the ELG Metals property, upgradient of the Seam Master property and downgradient of the Jervis property (Ref. 4, p. 8, 33 ; Ref. 17, p. 68, 70).

Ground water samples collected from boring SM

- 1 and monitoring well MW

- 14 are used to establish background levels for the contaminated ground water samples collected from borings

SM

- 6

- GW and SM

- 7

- GW listed below. Data are compared to background samples collected during the same sampling event using similar sampling methodology. Monitoring well MW

- 14 was purged at an average rate of approximately 0.3 gallons per minute for 97 minutes using a submersible pump. After purging was comp lete, ground water was sampled using a disposable bailer (Ref. 4, p. 13, 14, 50, 51). Boring SM

- 1 was drilled and when ground water was encountered, an in

- situ ground water sample was collected using a water sampling device. The water sampling device is inserted into undisturbed sediments at the base of the borehole. The outer portion of the water sampling device is then retracted to expose a stainless steel screen in

the water

- bearing zone. A stainless steel mini

- bailer is lowered into the screen for c ollection of

an in

- situ ground water sample. All samples were collected into pre

- preserved 40

- mL vials which were immediate capped and inverted to check for air bubbles to ensure zero headspace (Ref. 11, p. 27).

Sample

ID Well

Screened

Interval (ft bgs) Sampling

Date Hazardous

Substance Concentration

(ug/l) CRQL

(ug/l) References

SM

- 1

- GW 45

– 65 10/29/2002 TCE 7 0.5 Ref. 4, p. 345

- 351, 355; Ref. 11, p. 22 cis

- 1,2

- DCE 1 0.5

MW

- 14 30

– 60 11/5/2002 TCE 58 0.5 Ref. 4, p. 333

- 339; Ref. 17, p. 37 cis

- 1,2

- DCE 330 0.5

Notes:

CRQL: Contract Required Quantitation Limit ft bgs: feet below ground surface ug/l: micrograms per liter

- Contaminated Samples:

The borings listed below are located downgradient of the source at the Seam Master facility

. For conservative purposes, the higher concentration background levels from the November 2002 sampling event (MW

- 14) are compared to the October 2002 contaminated sample in order to establish a release. Sample locations are presented in Figure A

- 3 and Reference 4, page 33

.

Sample

ID Well

Screened

Interval (ft bgs) Sampling

Date Hazardous

Substance Concentration

(ug/l) CRQL

(ug/l) References

SM

- 6

- GW 45

– 65 10/29/2002 TCE 1,700 0.5 Ref. 4, p. 345

- 350; 353, 355; Ref. 11, p. 22

SM

- 7

- GW 45

– 65 10/30/2002 TCE 4,100 0.5 Ref. 4, p. 345

- 350; 353, 355; Ref. 11, p. 22September 2011 25

Sample

ID Well

Screened

Interval (ft bgs) Sampling

Date Hazardous

Substance Concentration

(ug/l) CRQL

(ug/l) References

SM

- 8

- GW 45

– 65 10/29/2002 TCE 4,000 0.5 Ref. 4, p. 345

- 350; 353, 355; Ref. 11, p. 22

SM

- 9

- GW 45

– 65 10/30/2002 TCE 17,000 0.5 Ref. 4, p. 345

- 350; 353, 355; Ref. 11, p. 22 cis

- 1,2

- DCE 8,000 0.5

Notes:

CRQL: Contract Required Quantitation Limit ft bgs: feet below ground surface ug/l: micrograms per liter

2009 Investigation Sampling

Between May 12 and 19, 2009, all new and existing ground water monitoring wells were sampled as part of the continued investigation of the Cooper Drum site. Two of the monitoring wells sampled were located directly down gradient of the Seam Master property (Ref. 17, p. 15, 68). All samples were analyzed for VOCs using EPA Method SOM01.2 (Ref.17, p. 15; Ref. 26, p. 1; Ref. 27, p. 1).

Ground water sample locations are shown in Figure A

- 3 and Reference 17, page 68.

- Background Concentrations:

Background levels for site

- related VOC hazardous substances are established below based on the analytical results from ground water collected from monitoring wells MW

- 10 and MW

- 14.

MW

- 10 is located in the southwest portion of the ELG Metals property, upgradient of the Seam Master property and downgradient of the Cooper Drum and Jervis properties. Monitoring well

MW

- 14 is located north of the Seam Master property on the ELG Metals property, upgradient of the Seam Master property and downgradient of the Jervis property (Ref. 17, p. 68, 70).

Monitoring wells MW

- 10 and MW

- 14 are used to establish back ground levels for the contaminated monitoring wells listed below. Background and downgradient monitoring wells are screened within the Gaspur aquifer (Ref. 17, p. 43, 44, 51, 52). Data are compared to background samples collected during the same sampling event using the same methodology. The sampling protocol employed standard low

- flow ground water sampling techniques with a

flow

- through cell. The monitoring wells were sampled using 2

- inch pumps with disposable discharge tubing. All samples were transp orted in a cooler packed with ice, under chain

- of

custody protocol (Ref. 17, p. 15).September 2011 26

Sample ID Well

Screened

Interval (ft bgs) Sampling

Date Hazardous

Substance Concentration

(ug/l) SQL

(ug/l) References

MW

- 10 45

– 74.5 5/14/2009 TCE 15 0.5 Ref. 17, p. 37, 56, 280; Ref. 26, p. 13, 135, 158; Ref. 28, p. 2 cis

- 1,2

- DCE 32 2.5

MW

- 14 30

- 60 5/14/2009 TCE 0.63 0.5 Ref. 17, p. 37, 57, 282; Ref. 26, p. 13, 198, 199; Ref. 28, p. 2 cis

- 1,2

- DCE 3.2 0.5

Notes:

ft bgs: feet below ground surface ug/l: micrograms per liter

U: The analyte was analyzed for but was not detected above the level of the reported sample quantitation limit SQL: Sample Quantitation Limit. The S QL s provided in this table are CLP contract

- required quantitation limits (CR Q Ls) for t hat analyte

with any dilution factors, volume adjustments, or percent solids for that analysis taken into account. SQLs were calculated as

follows:

Where:

Final volume (mL) is the final extract volume following sample preparat ion Initial volume (mL) is the volume of sample used

DF is the dilution factor

- Contaminated Samples:

The wells listed below are located downgradient of the sources at the Seam Master facility. For conservative purposes, the higher concentration background levels from the May 2009 sampling event (MW

- 10) are compared to the May 2009 contaminated sample in order to establish a

release. Well locations are presented in Figure A

- 3 , Referen ce 17, page 68 and Reference 22, page 68

.

Sample ID Well

Screened

Interval (ft bgs) Sampling

Date Hazardous

Substance Concentration

(ug/l) SQL

(ug/l) References

MW

- 34 58

- 68 5/16/2009 TCE 46 E 0.5 Ref. 17, p. 38, 61, 310; Ref. 27, p. 12, 306, 307; Ref. 28, p. 2 cis

- 1,2

- DCE 420 E 0.5

MW

- 35 95

- 105 5/16/2009 TCE 120 5.0 Ref. 17, p. 38, 61, 311; Ref. 26, p. 14, 257; Ref. 28, p. 2

Notes:

E: Concentration exceeds upper level of instrument calibration range (Ref. 17, p. 63) ft bgs: feet below ground surfaceSeptember 2011 27

ug/l: micrograms per liter SQL: Sample Quantitation Limit. The S QL s provided in this table are CLP contract

- required quantitation limits (CR Q Ls) for that analyte

with any dilution factors, volume adjustments, or percent solids for that analysis taken into account. SQLs were calculated as

follows:

Where:

Final volume (mL) is the final extract volume following sample preparation Initial volume (mL) is the volume of sample used

DF is the dilution factorMay 2012 28

At tribution

In the general vicinity of the Southern Avenue Industrial Area site (formerly referred to as the Seam Master Industries site), The Seam Master property is located at 5211 Southern Avenue, South Gate, Los Angeles County, California (Ref. 3; Ref. 4, p. 8; Ref. 5, p. 1). The property occupies approximately 3.85 acres (Ref. 6, p. 1; Ref. 7, p. 1). The Seam Master property

location i s presented in Figure A

- 1.

Since 1972, the Seam Master property has been operating as a hot

- melt adhesive manufacturing company (Ref. 4, p. 38). Inspections conducted by the DHS in 1985 and 1986 indicate that chlorinated hydrocarbons were used on the property (Ref. 8, p. 1, Ref. 9, p. 1). During the 1986 inspection, DHS observed one drum of retrograde TCE. A NOV was issued at this time due to the illegal storage of retrograde TCE and Seam Master was ordered to properly dispose of the waste (Ref. 9, p. 1; Ref. 10, p. 1).

In the South Gate area, shallow ground water occurs at a depth of approximately 45 feet bgs, with a ground water flow direction to the south or southeast. Shallow ground water in the vicinity of the Seam Master property is expected to be similar to the nearby Co oper Drum Company property, where it occurs within or is controlled by the near surface Bellflower Aquiclude, which incorporates the semi

- perched aquifer (Ref. 17, p. 8, 9; Ref. 22, p. 18, 19). In the vicinity of the Seam Master facility , the Lakewood For mation, which immediately underlies

the Bellflower Aquiclude , consists of the Gaspur aquifer, Exposition aquifer, an unnamed aquitard, and the Gage aquifer. Ground water flow within the Gaspur aquifer is generally to the

south beneath the Seam Master faci lity (Ref. 17, p. 70

– 72). Although data are not adequate to document ground water flow within the Exposition and Gage aquifers, it is assumed that the flow direction would be generally towards the south, in the direction of the Pacific Ocean (Ref. 20, p

. 2; Ref. 21, p. 182, 183, 184, Plate 6A (Geologic Section B

- B’); Ref. 23; Ref. 32; Figures A

- 1 and

A

- 2 of the HRS documentation record).

The Cooper Drum site (EPA ID: CAD055753370) is located at 9316 Atlantic Avenue in South Gate, California (Ref. 16, p. 1

- 2). The 3.8 acre facility is located approximately 300 feet northwest, and hydraulically upgradient, of the Seam Master property (Ref. 17, p. 7, 67, 70

- 72; Ref. 23). The Cooper Drum facility activities included drum reconditioning since the 1940s. Contaminants of concern associated with the Cooper Drum facility include TCE and cis

- 1,2

- DCE (Ref. 17, p. 7, 8). The Cooper Drum site was proposed to NPL on January 11, 2001 and received its final listing on NPL on June 14, 2001 (Ref. 16, p. 2). This HRS documentation record is a listing of releases from the Southern Avenue site, not from Cooper Drum, that are contributing to a TCE

- and cis

- 1,2

- DCE

- contaminated ground water plume (see Sections 2.2 and 3.0 of this HRS documentation record).

The Jervis B . Webb Co. site (EPA ID: CAD008339467) is located at 9301 Rayo Avenue in South Gate, California (Ref. 30, p. 1). The 3.82 acre facility is located approximately 750 feet north, and hydraulically upgradient, of the Seam Master property ( Ref. 17, p. 67, 70

– 72; Ref. 23). Investigations of the Jervis B. Webb Co. site have been conducted by EPA due to TCE and PCE ground water contamination. (Ref. 17, p. 21)

In 2002, a PA/SI was conducted on the Seam Master property. Ground water beneath the property and so ils on the property were sampled as part of the investigation. Soil samplesMay 2012 29

indicated that TCE and cis

- 1,2

- DCE were detected at concentrations above background concentrations (Ref. 4, p. 12). TCE was detected at a maximum concentration of 7.5 ug/kg and

c is

- 1,2

- DCE was detected at a maximum concentration of 6,100 ug/kg (Ref. 4, p. 410, 424).

Photographs taken in February 2011 show ed that although a majority of the Seam Master property is paved, the pavement is in poor condition and contains multiple cra c ks ( Ref. 14, p. 2, 3, 5). In addition, during the 2002 sampling event, there was no evidence that a liner or engineered cover were present at or beneath the ground surface (Ref. 4, p. 48). Precipitation

could infiltrate the contaminated soil beneath th e pavement.

Ground water samples collected beneath the property during the 2002 PA/SI indicated that TCE

and cis

- 1,2

- DCE were present in ground water at concentrations significantly above background

concentrations. Maximum concentrations of TCE and cis

- 1,2

- DCE detected were 17,000 ug/l and 8,000 ug/l, respectively (Ref. 4, p. 13). The maximum contaminant level (MCL) is 5 ug/l for TCE and 70 ug/l for cis

- 1,2

- DCE (Ref. 2). Background levels for Southern Avenue Industrial

Area

- related VOC hazardous subst ances were established based on the analytical results from ground water collected from boring SM

- 1 and monitoring well MW

- 14. Boring SM

- 1 was located northwest of the Seam Master property on the CEE Sportsware property, upgradient of the Seam Master prop erty and downgradient of the Cooper Drum and Jervis properties. Monitoring well MW

- 14 is located north of the Seam Master property on the ELG Metals property, upgradient of the Seam Master property and downgradient of the Jervis property (Ref. 4, p. 8, 34 ; Ref. 17, p. 68, 70).

Investigations conducted on the Cooper Drum site involved sampling ground water beneath and downgradient of the Seam Master property. In October 2000 a remedial investigation of the Cooper Drum site was conducted and depth

- discrete ground water samples were collected and analyzed at the Southern Avenue Industrial Area site (Ref. 14, p. 4; Ref. 22, p. 20). Analytical results indicated that ground water beneath the Seam Master property exhibited maximum concentrations of TCE at 8,000 ug/l and cis

- 1,2

- DCE at 4,900 ug/l (Ref. 22, p. 122). Background levels for Southern Avenue

- related VOC hazardous substances were established based on the analytical results from ground water collected from borings CPT

- 16 and CPT

- 20. Boring CPT

- 16 was l ocated northwest of the Seam Master property adjacent south to the ELG Metals building, upgradient of the Seam Master property production warehouse and raw material storage and downgradient of the Copper Drum and Jervis properties. Boring CPT

- 20 was

locat ed in the northeast portion of the Seam Master property, upgradient of the Seam Master production warehouse and raw material storage and downgradient of ELG Metals (Ref. 22, p. 51, 68, 83).

In May 2009, all new and existing ground water monitoring wells were sampled as part of the continued investigation of the Cooper Drum site. Two of the monitoring wells samples were located directly down gradient of the Seam Master property (Ref. 17, p. 15, 68). Analytical results indicated that ground water directl y down gradient of the Seam Master property exhibited maximum concentrations of TCE at 46 ug/l and cis

- 1,2

- DCE at 420 ug/l (Ref. 17, p. 61, 310). Background levels for Seam Master

- related VOC hazardous substances were established based on the analytical r esults from ground water collected from monitoring wells MW

- 10 and MW

14. MW

- 10 is located in the southwest portion of the ELG Metals property, upgradient of the Seam Master property and downgradient of the Cooper Drum and Jervis properties. MonitoringMay 2012 30

w ell MW

- 14 located north of the Seam Master property on the ELG Metals property, upgradient of the Seam Master property and downgradient of the Jervis property (Ref. 17, p. 68, 70).

The increased concentrations of cis

- 1,2

- DCE in correlation with the decreased concentrations of

TCE between the 2000/2002 release data and the 2009 release data is due to cis

- 1,2

- DCE being a degradation product of TCE (Ref. 31, p. 1). An NOV was issued in 1986 due to the illegal storage of TCE. TCE and cis

- 1,2

- DCE are ha zardous substances associated with the onsite source (Ref. 9, p. 1; Ref. 10, p. 1).

Ground water samples collected on and downgradient of the Seam Master property establish a release to the Gaspur aquifer (Ref. 4, p. 13; Ref. 17, p. 43, 44, 51, 52, 61, 1 01

– 103, 310; Ref. 22, p. 70, 122).

Interconnection between the Semi

- Perched, Gaspur, Exposition, and Gage A quifers is

established within 2 miles of Source 1 at the property as follows (Ref. 1, Section 3.0.1.2.1) :

 Contamination has been documented in two monitoring wells (MW

- 34 and MW

- 35) located directly downgradient of the Seam Master facility (Ref. 17, p. 15, 38, 61, 68, 310, 311). Monitoring wells MW

- 34 and MW

- 35 are screened w ithin the Gaspur A quifer (Ref. 17, p. 38, 51 ; Ref. 21, p. Plate 3A and 6A; Ref. 32 ). This supports the evidence that the Bellflower Aquiclude and Semi

- perched Aquifer are interconnected with the underlying formations (i.e., Lakewood Formation) since contaminants have passed through to th e lower aquifers.

 An examination of DWR Geologic Sections B

- B’ and L

- L’ indicates that the Gaspur

A quifer is in dire ct contact with the Exposition A quifer in the property vicinity (Ref . 21, Plates 3A, 6A, and 6E; Ref. 32, p. 2; Figures A

- 1 and A

- 2 of the HRS documentation record).

 An examination of DWR Geologic Section B

- B’ ind icates that the unnamed aquiclude

b etween the Exposition and Gage A quifers is not continuous within 2 miles of the

Southern Avenue Industrial Area site . This aquitard is shown as p inching out approximately 1,500 feet to the west of the property , resulting in a merging of the two aquifers [ Ref. 1, Section 3.0.1.2.1; Ref. 21 , Plates 3A and 6A (Geologic Section B

- B’); Ref. 32, p. 2; Figures A

- 1 and A

- 2 of the HRS documentation record ].

The Southern Avenue Industrial Area site is located in an urban area, in which numerous drinking water wells are located (Ref. 3; Ref. 14; Ref. 18; Ref. 19; Ref. 25; Ref. 32, p. 2; Figure

A

- 1 of the HRS documentation record). Eight drinking water wells screened within the Gage and Exposition Aquifers are located within 4 miles of Source 1 (Ref. 13, p. 2; Ref. 18; Ref. 19; Ref. 21, Plate 3A; Ref. 23; Ref. 25; Ref. 32, p. 2; Section 3.3.2.4 and Figure A

- 4 of the HRS documentation record).

An observed re lease to the aquifer has been documented in ground water samples collected at the

Southern Avenue Industrial Area site. H azardous substance s that meet the criteria for an observed release by chemical analysis were detected in Source 1 (see Section 2.2.2 of this documentation record). Background samples used to evaluate an observed release by chemical analysis is located upgradient of the source at the Jervis B. Webb site. An observed release of

TCE and cis

- 1,2

- DCE is documented from t he Seam Master property based on chemical analysis (see above tables in Section 3.1.1 of the HRS documentation record).May 2012 31

The evidence provided in this section of the HRS documentation record for the Southern Avenue

Industrial Area site documents that an observed release has occurred by chemical analysis of ground water samples to the Semi

- Perched / Gaspur/ Exposition/Gage interconnected aquifer of the hazardous substances listed below (Ref. 1, Sections 2.3 and 3.1.1).

Hazardous Sub stances Released

TCE and cis

- 1,2

- DCE

Ground Water Observed Release Factor Value: 550September 2011 32

3.1.2 POTENTIAL TO RELEASE

Potential to Release was not scored, because an Observed Release was established.September 2011 33

3.2 WASTE CHARACTERISTICS

3.2.1 TOXICITY/MOBILITY

Hazardous
Substance Source

No. Toxicity

Factor

Value

(Ref. 1,
Section 3.2.1.1) Mobility

Factor

Value * Does

Haz ardous
Substance

Meet

Observed Release? (Y/N) Toxicity/

Mobility Factor Values (Ref. 1, Section 3.2.1.3,

Table 3

- 9) Reference

TCE 1 10,000 1 Y 10,000 Ref. 12, p. 1

cis

- 1,2

- DCE 1 100 1 Y 100 Ref. 2, p. 5

* Hazardous substances meeting the criteria for an observed release by chemical analysis receive a mobility factor

valu e of 1 (Ref. 1, S ection 3.2.1.2).

Toxicity/Mobility Factor Value: 10,000 (Ref. 1, Section 3.2.1.3, Table 3

- 9)

Notes:

Y: Yes

N: NoSeptember 2011 34

3.2.2 HAZARDOUS WASTE QUANTITY

Source No. Source Type Source Hazardous Waste Quantity

1 Contaminated Soil >0

sum: >0

The hazardous waste quantity assigned from Section 2.4.2 of the HRS documentation record for Source 1 is unknown, but greater than 0. The hazardous waste quantity factor value assigned for the ground water pathway is 10 (Ref. 1, Sections 2.4.2.2 and 3.2.2 , Table 2

- 6).

Hazardous Waste Quantity Factor Value: 1 0

3.2.3 WASTE CHARACTERISTICS FACTOR CATEGORY VALUE

Toxicity/Mobility Factor Value: 10,000 Hazardous Waste Quantity Factor Value: 10

Toxicity/Mobility Factor Value X Hazardous Waste Quantity Factor Value: 100,000

Waste Characteristics Factor Category Value (subject to a maximum of 100 ): 1 8 (Ref. 1, Sections 2.4.3.1 and 3.2.3, Table 2

- 7)May 2012 35

3.3 TARGETS

The Southern Avenue Industrial Area site is located in an urban area, in which numerous drinking water wells are located (Ref. 13; Ref. 18; Ref. 19; Ref. 25; Figures A

- 1 and A

- 4 of the HRS documentation record). Ground water contamination within the Gaspur aquifer has been

identified at the Southern Avenue Industrial Area site (Ref. 4, p. 13, 14; Ref. 17, p. 43, 44, 51, 52; Ref. 22, p. 70). Eight drinking water wells screened within the Gage and Exposition aquifers are located within 4 miles of the source at the site (Ref. 13, p. 2; Ref. 18 ; Ref. 19; Ref. 21, Plate 3A; Ref. 25; Ref. 23; Sections 3.3.2.4 and Figure A

- 4 of the HRS documentation record). These wells were evaluated for potential contamination. Interconnections between the Semi

- perched, Gaspur, Exposition, and Gage aquifers is established within 2 miles of the source at the site and therefore are eligible to be scored as one interconnected aquifer (Ref. 1, Section 3.0.1.2.1; Ref. 21, Plates 3A, 6A, and 6E; Section 3.0.1, Figures A

- 1 and A

- 2 of the HRS documentation record).

3 .3.1 NEAREST WELL

Well ID: City of South Gate Well 24. This well is located 0.32 mile northeast of Source 1 at the site ( Ref. 13, p. 1 , 2; Figure A

- 4 of the HRS documentation record). Examination of DWR Plate 3A indicated that City of South Gate Well 24 is located nearest to transect line L

- L’

- L”, approximately 0.15 mile from Well A5 and 0.25 mile from Well B3 (Ref. 21, Plate 3A; Ref. 13; Ref. 32, p. 2). Examination of DWR geological section L

- L’

- L” indicates that the tip of the Gage Aquifer occurs at approximately 300 feet bgs and the bottom occurs at approximately 350 feet bgs in the vicinity of Wells 3S/12W

- 6A5 and 3S/12W

- 6B3 (Ref. 21, Plate 6E). The first perforation for City of South Gate Well 24 occurs at 310 feet bgs (Ref. 13). City of South G ate Well 24 is screened in the Gage Aquifer.

Level of Contamination (I, II, or potential): Potential. Sampling data are not available for this

well so Level I or II actual contamination cannot be documented.

Nearest Well Factor Value: 18

(Ref. 1, Table 3

- 11)

3.3.2 POPULATION

Within a 4

- mile radius of the site source, there are at least eight drinking water wells that serve a total population of approximately 62,256 people. The wells located within the 4

- mile radius encompass municipal drinking water wells ( Ref. 1, Sections 3. 0.1.1 and 3.3.2; Ref. 13; Ref. 18; Ref. 19; Ref. 25; Figure A

- 4 of the HRS documentation record).September 2011 36

3.3.2.1 Level of Contamination

3.3.2.2 Level I Concentrations

Level I Concentrations are not assigned.

Level I Concentrations Factor Value: 0

3.3.2.3 Level II Concentrations

Level II Concentrations are not assigned.

Level II Concentrations Factor Value: 0September 2011 37

3.3.2.4 Potential Contamination

Four municipalities that have public water systems located within 4 miles of the sources at the site were evaluated (Figure A

- 4 of the HRS documentation record; Ref. 1, Section 3.3.2). The four municipalities are the City of South Gate, Walnut Park Mutual Water Company, Maywood Mutual Water Company #3, and City of Lynwo od. Each municipality’s water supply system is

described below.

City of South Gate The City of South Gate operates a drinking water system that serves approximately 96,375 people. Currently, the City of South Gate obtains all of its drinking water from ground water. The blended system consists of seven active drinking water wells (Wells 14, 19, 24, 25, 26, 27 and 28), four stand

- by wells (Wells 14, 19, 22B, 23), and most recently one destroyed (Well 7). No single well provides more than 40 percent of t he total demand at any given time. Wells 14 and 19 provide 30 percent of the demand, Wells 24 and 25 provide 20 percent of the demand, Well 26 provides 20 percent of the demand, Well 27 provides 10 percent of the demand, and Well 28 provides 20 percent of the demand. The City of South Gate does not sell or purchase water to other water systems and/or water users. In 2002, water quality sampling detected TCE in standby Well 7 at a concentration of 10.5 parts per million (Ref. 13).

Examination of DWR Pla te 3A indicated that City of South Gate Well 24 is located nearest to

transect line L

- L’

- L”, approximately 0.15 mile from Well A5 and 0.25 mile from Well B3 (Ref. 21, Plate 3A; Ref. 13; Ref. 32, p. 2). Examination of DWR geological section L

- L’

- L” indicat es that the tip of the Gage Aquifer occurs at approximately 300 feet bgs and the bottom occurs at approximately 350 feet bgs in the vicinity of Wells 3S/12W

- 6A5 and 3S/12W

- 6B3 (Ref. 21, Plate 6E). The first perforation for City of South Gate Well 24 occur s at 310 feet bgs (Ref. 13). City of South Gate Well 24 is screened in the Gage Aquifer.

Calculation: 96,375 people/7 wells = 13,767.85 people per well

Walnut Park Mutual Water Company
The Walnut Park Mutual Water Company operates a drinking water system that serves approximately 17,000 people. The system consists of two active drinking water wells, Well 10 and Well 11, and one standby well, Well 12. Currently, Well 12 is non

- operational and not contributing any water to the system. Walnut Park M utual Water Company does not sell or purchase water from any other water purveyors. All of the water distributed by Walnut Park Mutual Water Company is from ground water. Water from the two wells is blended evenly prior to distribution (Ref. 18).

Examin ation of DWR Plate 3A indicated that Walnut Park Mutual Water Company Wells 10 and

11 are located nearest to transect line K

- K’

- K”, approximately 0.25 mile from Wells P2 and B1 (Ref. 3; Ref. 18; Ref. 21, Plate 3A; Ref. 32, p. 2; Figure A

- 1 of the HRS docum entation record). Examination of DWR geologic section K

- K’

- K” indicates that the tip of the Exposition Aquifer occurs at approximately 150 feet bgs and the bottom occurs at approximately 250 feet bgs in the vicinity of Wells 2S/13W

- 22P2 and 2S/13W

- 27B11 ( Ref. 21, Plate 6E). The first perforations for Walnut Park Mutual Water Company Wells 10 and 11 occur at 205 feet bgs and 203 feet bgs,September 2011 38

respectively (Ref. 18). Wells 10 and 11 are screened in the Exposition aquifer.

Calculation: 17,000 people/2 wells = 8,500 people per well

Maywood Mutual Water Company #3
The Maywood Mutual Water Company #3 operates a drinking water supply system that contains three active drinking water wells (Prospect #1, District #4, and Warehouse #7) that serve approximately 9,500 people. The Maywood Mutual Water Company #3 obtains all of its drinking water from ground water. The Prospect #1 well contributes 22.7 percent to the system, the District #4 well contributes 34.9 percent to the system, and the Warehouse #7 well

contribu tes 42.4 percent to the system. The Maywood Mutual Water Company #3 does not purchase or sell their water to any other water purveyors. All three wells are screened in the Exposition Aquifer ( Ref. 19).

Well Name Gallons Per

Minute (gpm) Percentage of

Supply Associated Population Reference

Prospect #1 700 22.7 9,500 * 0.227 = 2,156.5 Ref. 19

District #4 1,300 34.9 9,500 * 0.349 = 3,315.5 Ref. 19

Warehouse #7 1,000 42.4 9,500 * 0.424 = 4,028 Ref. 19

City of Lynwood
The City of Lynwood operates a drinking water supply system that contains five active drinking water wells (Wells 5, 8, 9, 11, and 19) that serve approximately 65,965 people. Currently, all of the water is obtained from ground water, however approximately one to two percent of the water distributed is purchased from the Municipal Water District, on an as needed basis. No one well supplies more than 40 percent to the entire system. Well 5 contributes 9.73 percent to the system, Well 8 contributes 19.47 pe rcent to the system, Well 9 contributes 21.24 percent to the system, Well 11 contributes 14.16 percent to the system, and Well 19 contributes 35.4 percent to the system (Ref. 25).

Examination of DWR Plate 3A indicated that City of Lynwood Well 8 is located nearest to

transect line C

- C’

- C”, approximately 0.75 mile from Well Q1 (Ref. 21, Plate 3A; Ref. 25; Ref. 32, p. 2). Examination of DWR geologic section C

- C’

- C” indicates that the tip of the Exposition Aquifer occurs at approximately 175 feet bgs and the bottom occurs at approximately 260 feet bgs in the vicinity of Well 3S/13W

- 12Q1 (Ref. 21, Plate 6B). Perforations for City of Lynwood Well 8 occur at 161 to 175 feet bgs, 207 to 2 16 feet bgs, and 241 to 247 feet bgs (Ref. 25). Well 8 is screened in the Exposition Aquifer.

Examination of DWR Plate 3A indicated that City of Lynwood Well 19 is located nearest to

transect line K

- K’

- K”, approximately 1 mile from Well H1 and adjacent to the C

- C’

- C” transect line (Ref. 21, Plate 3A; Ref. 25; Ref. 32, p. 2). Examination of DWR geologic section K

- K’

- K” indicates that the tip of the Gage aquifer occurs at approximately 250 feet bgs and the bottom occurs at approximately 300 feet bgs in t he vicinity of Well 3S/13W

- 15H1 (Ref. 21, Plate 6E). The City of Lynwood Well 19 is screened from 250 to 878 feet bgs (Ref. 25). Well 19 is screened in the Gage Aquifer.September 2011 39

Calculation: 65,965 people/6= 10,994.16 people per well/water source

Distance

- We ighted Population Values

Distance Category (miles) Public and Private Wells

(Figure A

- 4 of the HRS documentation record) Population

Served Reference Distance

- Weighted Population Value (Ref. 1, Section 3.3.2.4, Table 3

- 12)

0 to

- 1/4 Total 0 0

> 1/4 to 1⁄2 Total 13,767.85 10,122

City of South Gate Well 24 13,767.85 Ref. 13

> 1⁄2 to 1 Total 0 0

> 1 to 2 Total 10,994.16 2,939

City of Lynwood Well 8 10,994.16 Ref. 25

> 2 to 3 Total 9,500 678

Maywood Mutual #3 Prospect #1 2,156.5 Ref. 19 Maywood Mutual #3 District #4 3,315.5 Ref. 19 Maywood Mutual #3 Warehouse #7 4,028 Ref. 19

> 3 to 4 Total 27,994.16 1306

Walnut Park Mutual Well 10 8,500 Ref. 18

Walnut Park Mutual Well 11 8,500 Ref. 18 City of Lynwood Well 19 10,994.16 Ref. 25

TOTAL: 15,045

Sum of Distance

- Weighted Population Values: 15,045

Sum of Distance

- Weighted Population Values/10: 1,504.5 rounded to 1,504

Potential Contamination Factor Value: 1,504

3.3.3 RESOURCES

There is no information indicating that ground water drawn from any target well within 4 miles of the source at the site is used for commercial food/forage crop irrigation, livestock watering, commercial food preparation, or commercial aquaculture. It is likely that there are municipal and/or community swimming pools within the target distance limit that may be utilizing ground water from the aquifers being evaluated. However, the evaluation of resources would not affect the final HRS score or the listing decision.

Resources Factor Value: 0May 2012 40

3.3.4 WELLHEAD PROTECTION AREA

The Wellhead Protection Area Factor Value was not evaluated for the Southern Avenue

Industrial Area HRS documentation record since the evaluation would not affect the final HRS site score or the listing decision.

Wellhead Protection Area Factor Value: 0September 2011 41



# Attachment AFigure A-1 0 0

. 5 Mile Property Location Map
Seam Master Industries
5211 Southern Avenue South Gate, California i h

Property
Location

Base Map: South Gate Quadrangle 7.5 Minute Series (Topographical), USGS 1981, National Geographic TOPO!0FeetLegendFacility BoundarySumpFormerAbove GroundStorage TanksPallet Production AreaSeam Master IndustriesProduction Warehouse

S o u t h e r n A v e n u e R

a

i l r o

a

d

A d

e

l l a A v

e

n

u

eParking LotFormerAbove GroundStorage TanksConcrete Linersfor FormerAbove GroundStorage TanksUndergroundStorage TankRaw MaterialStorageDrum StorageOffice S

h

e

dFacility Layout MapSeam Master Industries5211 Southern AvenueSouth Gate, CaliforniaFigureA-2Base Map: USA Prime Imagery, Los Angeles, Aerials Express 2009.Facility Features from: Weston Solutions, Inc.,Preliminary Assessment/Site Inspection Report, Seam Master Industries,South Gate, California, May 8, 2003.100+U+U+U+U+ U+ U+ U+ U+ U&.&.&.0 100FeetLegendFacility Boundary+UMonitoring Well+ UGrab Groundwater Sample&.CPT SampleSeam Master IndustriesProduction Warehouse

S o u t h e r n A v e n u e R

a

i l r

o

a

d

A d

e

l l a A v

e

n

u

e G r o u n d w a t e r
F l o w D i r e c t i o nCPT-20 BkgCPT-21CPT-16 BkgMW-10 BkgMW-34MW-35MW-14 BkgSM-1-GW BkgSM-7-GWSM-7-S2SM-7-S5SM-8-GWSM-6-GWSM-9-GWMW-34MW-35Historic Sample Location MapSeam Master Industries5211 Southern AvenueSouth Gate, CaliforniaFigureA-3Base Map: USA Prime Imagery, Los Angeles, Aerials Express 2009.CPT and Well Locations from: Innovative Technical Solutions, Inc.,Cooper Drum Company Superfund Site Remedial Design TechnicallMemorandum for Field Sampling Results, Addendum No. 4, February 26, 2010.Grab Groundwater Samples Locations from: Weston Solutions, Inc.,Preliminary Assessment/Site Inspection Report, Seam Master Industries,South Gate, California, May 8, 2003.! 5

& < & < & < & < & < & < & <

& <

Figure A-4 Legend

& < Drinking Water Well

! 5 Source Boundary

Facility Boundary

Well Search Radius

0.25 mile

0.5 mile

1 mile

2 miles

3 miles

4 miles 0 1 Mile

Walnut Park
Well 10
Well 11 Maywood Mutual #3
Warehouse #7

Maywood Mutual #3
District #4

Maywood Mutual #3 Prospect #1

City of South Gate
Well 24

Drinking Water Well Radius Map
Seam Master Industries
5211 Southern Avenue South Gate, California City of Lynwood
Well 8

City of Lynwood
Well 19

Base Map: World Street Map: 2009 ESRI, DeLorme, NAVTEQ, TomTom, USGS, Intermap, AND, ESRI Japan, METI, ESRI Hong Kong, ESRI Thailand, Procalculo Prosis.

Well Locations from: Hernandez, Ron, City of South Gate, Telephone Conversation recorded on Contact Report by Anitra B. Rice and Amanda K.C. Reilly, Weston Solutions, Inc., January 4 and June 22, 2011. Gonzalez, Martin, Walnut Park Mutual Water Company, Telephone Conversation recorded on Contact Report by Anitra B. Rice and Amanda K.C. Reilly, Weston Solutions, Inc., October 29, 2010 and June 30, 2011. Rohlf, Bob, Maywood Mutual Water Company #3, Telephone Conversation recorded on Contact Report by

A nitra B. Rice and Amanda K.C. Reilly, Weston Solutions, Inc., December 2, 2010 and August 24, 2011. Molina, Jose, City of Lynwood Public Works, Telephone Conversation recorded on Contact Report by Karen Jurist, USEPA, May 25, 2011.