COVER SHEET 

Name of Site: St. Clair Shores Drain 

EPA ID No.: MIN000510063 

Contact Person

United States Environmental Protection Agency (EPA), Region V 

 Patrick Hamblin 

77 West Jackson Boulevard, Mail Code: SR-6J 

Chicago, Illinois 60604 

 (312) 886-6312 

Site Investigation: Joseph Walczak 

 Michigan Department of Environmental Quality 

 (517) 373-4951 

Pathways, Components, or Threats Not Scored

The ground water migration, ground water to surface water migration, soil exposure and air migration 

pathways are not scored as part of this Hazard Ranking System (HRS) evaluation. The ground water, 

ground water to surface water, soil exposure, and air migration pathways were not included because a 

release to these media does not significantly affect the overall site score and because the surface water 

migration pathway produces an overall site score above the minimum required for the site to qualify for 

inclusion on the National Priorities List (NPL). 

Ground Water Migration Pathway: There are insufficient data to document the HRS requirements for 

establishing the threat of release via ground water at the St. Clair Shores Drain Site. 

Soil Exposure Pathway: While there could be potential for contact with contaminated media, the 

evaluation of this pathway does not affect the listing decision. 

Air Migration Pathway: The majority of surficial and shallow PCB contaminated soil has been 

removed and the majority of the PCB contamination is located over 2 feet below ground surface, in the 

storm sewer system, or below water in canal and lake sediments. Therefore, the air pathway at the St. 

Clair Shores Drain Site was not scored. 
HRS DOCUMENTATION RECORD 

Name of Site: St. Clair Shores Drain Date Prepared: March 2010 

EPA Region: V

Street Address*: Intersection of Bon Brae Street and Harper Avenue 

City, County, State, Zip Code: St. Clair Shores, Macomb County, Michigan, 48081 (Figure 1) (Refs. 

3; 4) 

General Location in State: Southeast Michigan 

Topographic Map: 7.5-Minute Series Topographic Map: Grosse Pointe Quadrangle, 

Michigan, 1968 (Photorevised 1983) (Ref. 3). 

Latitude: 42o 29’ 13” North (Refs. 3; 4, pp. 1, 2) 

Longitude: 82o 53’ 57” West (Refs. 3; 4, pp. 1, 2) 

The latitude and longitude listed above mark the location of the Intersection of Bon Brae Street and 

Harper Avenue (Ref. 4, pp. 1, 2; Figure 1 of this HRS documentation record). 

*The street address, 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 to 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 delineated boundaries. A site is defined as where a hazardous substance 

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 the Comprehensive Environmental Response, Compensation, and Liability Act 

(CERCLA). Accordingly, EPA contemplates that the preliminary description of site boundaries at the 

time of scoring will be refined as more information is developed regarding where the contamination has 

come to be located. 

Scores

Ground Water Migration Pathway 0.00 

Surface Water Migration Pathway 97.76 

Soil Exposure Pathway 0.00 

 Air Pathway 0.00

HRS SITE SCORE 48.88

1 
WORKSHEET FOR COMPUTING HRS SITE SCORE 

 S S2

1. Ground Water Migration Pathway Score (Sgw) 

(from Table 3-1, line 13) NS

2a. Surface Water Overland/Flood Migration Component 

(from Table 4-1, line 30) 97.76 9557.0176

2b Ground Water to Surface Water Migration Component 

(from Table 4-25, line 28) NS

2c. Surface Water Migration Pathway Score (Ssw) 

 (enter the larger of lines 2a and 2b as the pathway score) NS 9557.0176

3. Soil Exposure Pathway Score (Ss) 

(from Table 5-1, line 22) NS NS

4. Air Migration Pathway Score (Sa) 

(from Table 6-1, line 12) NS NS

5. Total of Sgw

2

 + Ssw 2

+ Ss

2 + Sa2

 9557.0176

6. HRS Site Score 48.88

 Divide the value on line 5 by 4 and take the square root. 

Note: 

NS -- Not Scored 

2 
3 

SURFACE WATER OVERLAND FLOW/FLOOD MIGRATION COMPONENT SCORESHEET 

Factor Categories and Factors 

DRINKING WATER THREAT 

Maximum 

Value 

Assigned Value

Likelihood of Release 

1. Observed Release 

2. Potential to Release by Overland Flow: 

 2a. Containment 

 2b. Runoff 

 2c. Distance to Surface Water 

 2d. Potential to Release by Overland Flow (lines 2a[2b + 2c]) 

3. Potential to Release by Flood: 

 3a. Containment (Flood) 

 3b. Flood Frequency 

 3c. Potential to Release by Flood (lines 3a x 3b) 

4. Potential to Release (lines 2d + 3c, subject to a maximum of 

500) 

5. Likelihood of Release (higher of lines 1 and 4) 

550 

10 

25 

25 

500 

10 

50 

500 

500 

550 

550 

NS 

550 

Waste Characteristics 

6. Toxicity/Persistence 

7. Hazardous Waste Quantity 

8. Waste Characteristics 

* 

* 

100 

10,000 

100 

32 

Targets 

9. Nearest Intake 

10. Population 

10a. Level I Concentrations 

10b. Level II Concentrations 

10c. Potential Contamination 

10d. Population (lines 10a+10b+10c) 

11. Resources 

12. Targets (lines 9 + 10d + 11) 

50 

** 

** 

** 

** 

5 

** 

1 

0 

0 

2 

2 

5 

8 

13. DRINKING WATER THREAT SCORE 100 1.70 

Notes: 

* -- Maximum value applies to waste characteristics category 

** -- Maximum value not applicable 

NS -- Not Scored 
4 

SURFACE WATER OVERLAND FLOW/FLOOD MIGRATION COMPONENT SCORESHEET 

Factor Categories and Factors 

HUMAN FOOD CHAIN THREAT 

Maximum 

Value 

Assigned Value

Likelihood of Release 

14. Likelihood of Release (same as line 5) 550 550 

Waste Characteristics 

15. Toxicity/Persistence/Bioaccumulation 

16. Hazardous Waste Quantity 

17. Waste Characteristics 

* 

* 

1000 

5 x 10

8

100 

320 

Targets 

18. Food Chain Individual 

19. Population 

 19a. Level I Concentrations 

 19b. Level II Concentrations 

 19c. Potential Contamination 

 19d. Population (lines 19a+19b+19c) 

20. Targets (lines 18 + 19d) 

50 

** 

** 

** 

** 

** 

** 

45 

0 

0.03 

0 

0.03 

45.03 

21. HUMAN FOOD CHAIN THREAT SCORE 100 96.06 

Notes: 

* -- Maximum value applies to waste characteristics category 

** -- Maximum value not applicable
5 

SURFACE WATER OVERLAND FLOW/FLOOD MIGRATION COMPONENT SCORESHEET 

Factor Categories and Factors 

ENVIRONMENTAL THREAT 

Maximum 

Value 

Assigned Value

Likelihood of Release 

2. Likelihood of Release (same as line 5) 550 NS 

Waste Characteristics 

23. Ecosystem Toxicity/Persistence/Bioaccumulation 

24. Hazardous Waste Quantity 

25. Waste Characteristics 

* 

* 

1000 

NS

NS 

NS 

Targets 

26. Sensitive Environments 

26a. Level I Concentrations 

26b. Level II Concentrations 

26c. Potential Contamination 

26d. Sensitive Environments (lines 26a+26b+26c) 

27. Targets 

** 

** 

** 

** 

** 

NS 

NS 

NS 

NS 

NS 

28. ENVIRONMENTAL THREAT SCORE 60 NS 

29. WATERSHED SCORE 100 97.76 

30. SURFACE WATER 

 OVERLAND FLOW/FLOOD COMPONENT SCORE 100 97.76 

Notes: 

* -- Maximum value applies to waste characteristics category 

** -- Maximum value not applicable 

NS -- Not Scored 




10 

REFERENCES 

1. U. S. Environmental Protection Agency (EPA). Hazard Ranking System Final Rule. Title 40 of the 

Code of Federal Regulations (CFR), Part 300, Appendix A. 139 Pages. 

http://www.epa.gov/superfund/sites/npl/hrsres/rule/part1_2.pdf

http://www.epa.gov/superfund/sites/npl/hrsres/rule/part3a.pdf

http://www.epa.gov/superfund/sites/npl/hrsres/rule/part3b.pdf

http://www.epa.gov/superfund/sites/npl/hrsres/rule/part3c.pdf

http://www.epa.gov/superfund/sites/npl/hrsres/rule/part4a.pdf

http://www.epa.gov/superfund/sites/npl/hrsres/rule/part4b.pdf

http://www.epa.gov/superfund/sites/npl/hrsres/rule/part5.pdf

http://www.epa.gov/superfund/sites/npl/hrsres/rule/toc_sec1.pdf

http://www.epa.gov/superfund/sites/npl/hrsres/rule/sec2.pdf

http://www.epa.gov/superfund/sites/npl/hrsres/rule/sec3.pdf

http://www.epa.gov/superfund/sites/npl/hrsres/rule/sec4a.pdf

http://www.epa.gov/superfund/sites/npl/hrsres/rule/sec4b.pdf

http://www.epa.gov/superfund/sites/npl/hrsres/rule/sec4c.pdf

http://www.epa.gov/superfund/sites/npl/hrsres/rule/sec4d.pdf

http://www.epa.gov/superfund/sites/npl/hrsres/rule/sec5.pdf

http://www.epa.gov/superfund/sites/npl/hrsres/rule/sec6.pdf

http://www.epa.gov/superfund/sites/npl/hrsres/rule/sec7.pdf

2. EPA. Superfund Chemical Data Matrix (SCDM), SCDM Data Versions: January 2004. Excerpt. 1 

page. A complete copy of SCDM can be found at: 

http://www.epa.gov/superfund/sites/npl/hrsres/tools/scdm.htm 

3. U.S. Geological Survey (USGS). 7.5-Minute Series Topographic Map: Grosse Pointe Quadrangle, 

Michigan, 1968 (Photorevised 1983). 1 Page. 

4. Weston Solutions, Inc. (WESTON). Longitude and Latitude Determination. August 31, 2009. 2 

Pages. 

5. State of Michigan, Department of Environmental Quality (MDEQ). Site Inspection Report, St. Clair 

Shores Drain. December 3, 2009. 387 Pages. 

6. EPA, Site Assessment Report, Ten Mile Drain Polychlorinated Biphenyl Investigation Site, St. Clair 

Shores, Macomb County, Michigan, Volume I of II. Prepared by Tetra Tech EM Inc., July 31, 2002. 

249 Pages. 

7. U.S. Department of Health and Human Services. Ten Mile Lange/Revere Drainage System, Petitioned 

Health Consultation, December 20, 2002. 60 Pages. 

8. WESTON. April-May 2005 Site Investigation Report and Focused Feasibility Study, Volume I of II, 

St. Clair Shores Drain Site. October 2005. 194 Pages. 

8A. MDEQ, Work Plan/Safety Plan, 10 Mile Drain Area, Macomb County, Michigan. April 6, 2005. 19 

Pages. 

8B. WESTON. April-May 2005 Site Investigation Report and Focused Feasibility Study, Analytical 

Results, Volume II of II, St. Clair Shores Drain Site. October 2005. 873 Pages. 
11 

8C. Weston Solutions Inc., Work Plan, For Source Area Investigation Activities at the Ten Mile Drain 

Site, Macomb County, Michigan, May 2005. 60 Pages. 

9. MDEQ. Analytical Results, Laboratory Work Order # 50400038, Report Date, April 22, 2005. 12 

Pages. 

10. MDEQ. Analytical Results, Laboratory Work Order # 50400036, Report Date, April 14, 2005. 14 

Pages. 

11. MDEQ. Analytical Results, Laboratory Work Order # 50400037, Report Date, April 22, 2005. 12 

Pages. 

12. MDEQ. Analytical Results, Laboratory Work Order # 50400039, Report Date, April 22, 2005. 11 

Pages. 

13. MDEQ. Analytical Results, Laboratory Work Order # 50400050, Report Date, April 27, 2005. 9 

Pages. 

14. EPA. Pollution Report, St, Clair Shores Drain, June 13, 2006. 4 Pages. 

15. WESTON. Removal Report, St. Clair Shores PCB Site, April 2007. 9 Pages. 

16. WESTON. 15-Mile Target Distance Limit Map. August 28, 2009. 1 Page. 

17. EPA. Contract Required Quantitation Limits for SOM01.2. 1 Page. 

17A. MDEQ. Surface Water/Sediment Sampling Data Sheets, July 28-30, 2008. 30 Pages. 

18. WESTON. Record of Telephone Conversation between Gary White, Macomb County Health 

Department, and Lauren Cook, WESTON. September 8, 2009. 1 Page. 

19. St. Clair River and Lake St. Clair Comprehensive Management Plan. June 2004. Excerpt, 22 Pages. 

Available in its entirety at http://www.glc.org/stclair/. 

20. U.S. Department of Health and Human Services. Health Consultation, St. Clair Shores PCBs – 

Residential Soils. November 27, 2007. 23 Pages. 

21. Michigan Department of Community Health. 2002. Michigan Family Fish Consumption Guide. 25 

Pages. 

22. Michigan Department of Community Health. 2009. Michigan Family Fish Consumption Guide. 32 

Pages. 

23. Great Lakes Fishery Commission. Draft Fish Community Goal and Objectives for Lake St. Clair, St. 

Clair River and Detroit River, March 28, 2003. 44 Pages. 

24. Lake St. Clair: Its Current State and Future Prospects. Conference Summary Report, November 30-

December 1, 1999. 70 Pages. 

25. WESTON. Record of Telephone Conversation between Chuck Bellmore, Mount Clemens Water 

Department, and Lauren Cook, WESTON. November 24, 2009. 1 Page. 

26. Reference reserved. 
12 

27. WESTON. Record of Telephone Conversation between Antoine Pogue, Highland Park Water 

Department, and Lauren Cook, WESTON. November 24, 2009. 1 Page. 

28. Reference reserved. 

29. WESTON. Record of Telephone Conversation between Scott Homminga, Gross Pointe Farms Water 

Department, and Lauren Cook, WESTON. September 8, 2009. 1 Page. 

30. WESTON. Population Calculation for City of Detroit Water Intake, Omprakash Patel, December 1, 

2009. 3 Pages. 

31. WESTON. Record of Telephone Conversation between Ron Hayes, Detroit Water Department, and 

Lauren Cook, WESTON. December 2, 2009. 2 Pages. 

32. MDEQ, Laboratory Services Section, Quality Assurance Program Plan, May 5, 2003. 192 Pages. 

33. Great Lakes Information Network (GLIN), Lake St. Clair. http:/www.greatlakes.net/lakes/stclair.html. Accessed November 20, 2009. 3 Pages. 

34. MDEQ, Interoffice Communication, Fish Consumption Documentation for Lake St. Clair, Joseph 

Walczak, October 20, 2009. 1 Page. 
13 

1.0 SITE DESCRIPTION 

The St. Clair Shores Drain (SCSD) comprises an enclosed concrete storm sewer system surrounded by sand 

and gravel fill materials placed in native clay soils. The SCSD is located in a mixed residential/commercial 

area in St. Clair Shores, Macomb County, Michigan, near the western shore of Lake St. Clair (Refs. 5, p. 5; 6, 

p. 9). The SCSD storm sewer system drains approximately 0.5 square mile of the city of St. Clair Shores and 

terminates in an outfall on the Lange Street Canal (Ref. 8, p. 9). The Lange Street Canal then branches into 

two parallel canals, the Lange Street Canal and the Revere Street Canal, both of which drain into Lake St. 

Clair. The two canals are bordered by residences along three streets (Ref. 6, p. 12). Figure 1 is site location 

map. 

In 2001, the county collected sediment samples from the Lange Street Canals in order to secure a dredging 

permit (Ref. 7, p. 9). Analytical results revealed polychlorinated biphenyls (PCBs) at concentrations up to 150 

parts per million (ppm) in the canal sediments (Ref. 7, pp. 9, 37). As a result, the Michigan Department of 

Environmental Quality (MDEQ) and the Macomb County Public Works Office (MCPWO) initiated an 

investigation of the SCSD in February 2002 (Ref. 8, p. 10). PCBs were detected at a number of locations 

within the SCSD concrete piping, with the highest concentration being found at the intersection of Harper 

Avenue and Bon Brae Avenue (Ref. 8, p. 11). 

Subsequently, EPA and MCPO conducted sediment removal and dewatering activities within a combined total 

of 5.5 miles of SCSD concrete piping (Ref. 8, p.11). However, monitoring efforts in 2003 and 2004 revealed 

the renewed presence of PCB-contaminated sediment and water within the SCSD drainage system (Ref. 8, 

p.11). EPA, MDEQ, MCPWO, and the city of St. Clair Shores have coordinated efforts to identify potential 

source areas and investigate potential migration pathways into or out of the SCSD. These investigations 

resulted in the discovery of PCBs located in the soils adjacent to the drain in several areas and in surficial soils 

in the area of Bon Brae and Harper Avenues (Ref. 8, pp.11, 12, Figs. 2 and 3). Figure 2 is an MDEQ soil 

boring location map, and Figure 3 is an MDEQ/EPA soil boring location map. 

In 2006, EPA excavated surficial PCB-contaminated soils from several residential properties which were 

identified during the previous investigations, and installed an impermeable liner in the storm drain in the 

vicinity of Harper and Bon Brae Avenues, as a temporary measure to prevent PCBs from continuing to enter 

the drain (Ref. 5, p. 9). EPA also injected slurry into the soils of the utility corridor near the terminus of the 

liner to prevent PCBs from migrating through the soils in this vicinity (Ref. 5, p. 9). 

It was subsequently determined that the site should be evaluated through the CERCLA site assessment process 

(Ref. 5, p. 6). MDEQ completed a Preliminary Assessment in June 2008, completed a Site Inspection (SI) 

Work Plan on July 3, 2009, and conducted SI field work July 28-30, 2008 (Ref. 5, p. 6). The scope of the SI 

included surface water and sediment sampling of the canals that currently receive drainage from the SCSD, as 
14 

well as surface water and sediment sampling of Lake St. Clair and two canals that historically received 

drainage from an open drain in the vicinity of the SCSD (Ref. 5, pp. 6, 7, 16, Fig. 4). Findings of the SI 

revealed PCB contamination at varying levels in all of the water bodies sampled (Ref. 5, pp. 6, 7, 16). Figure 

4 is a sediment sample location map corresponding to the SI sampling event. Lake Saint Clair and associated 

canals are used for recreation and fishing (Ref. 5, p.19). 

Several sediment samples have exceeded TSCA Subpart D Cleanup Standards of 1,000 μg/kg; U. S. EPA 

Region 5 RCRA Ecological Screening Levels for sediments (59.8 μg/kg); MDEQ Part 201 Residential and 

Commercial I Direct Contact Criteria of 4,000 μg/kg; and several other recommended guidance limits and 

effect levels (Ref. 5, p. 59), 

The site, as currently scored for HRS purposes, includes the contamination within the SCSD concrete sewer 

pipes and contaminated subsurface soil surrounding the SCSD concrete pipe. The contaminated soil 

surrounding the SCSD pipes was documented through soil sampling at various depths near the intersection of 

Harper and Bon Brae Avenues. In addition, there is an observed release of PCBs to the sediments of Lange 

and Revere Street Canals, as well as to Lake St. Clair. 
15 

2.2 SOURCE CHARACTERIZATION 

2.2.1 Source Identification 

Number of the source: 1 

Name and description of the source: Contamination in the SCSD sewer pipes and subsurface contaminated 

soil surrounding the SCSD sewer pipes. 

Source Type: Other -- Source type "other" was chosen because the contamination in the SCSD sewer pipes 

and subsurface contaminated soil surrounding the pipes fit no other HRS category. 

Source 1 consists of PCB contamination in the SCSD storm sewer pipes which are connected to the drain 

discharging into the Lange Street and Revere Street canals and leaking to/from the subsurface contaminated 

soil surrounding the pipes. In 2001, MCPWO collected sediment samples from the Lange Street canals to 

support its efforts to secure a dredging permit (Ref. 7, p. 9). The analytical data results indicate the presence of 

PCBs at concentrations up to 150 ppm in canal sediment samples (Ref. 7, pp. 9, 37). As a result, MDEQ and 

MCPWO initiated an investigation of the SCSD utility corridor in February 2002. The highest concentration 

of PCBs (3,270 ppm) was detected in sediment samples collected within the SCSD concrete piping at the 

intersection of Harper Avenue and Bon Brae Street (Ref. 8, p.11). EPA initiated sediment removal and 

dewatering activities in 2002 in the areas of the SCSD concrete piping exhibiting the highest levels of PCB 

contamination. EPA vacuumed and power jetted approximately 1.25 miles of SCSD concrete piping from 

Lakeland Boulevard to Bon Brae Street and from Harper Avenue to the SCSD outlet at the Lange Street canals 

(Ref. 8, p.11). MCPWO conducted sediment removal and dewatering activities along 4.25 miles of the 

remaining 5.75 miles of the SCSD concrete piping in the project area and installed steel plates near the SCSD 

outlet structure to trap and prevent additional discharge of PCB-contaminated sediments into the canal (Ref. 8, 

p.11). 

Monitoring efforts in 2003 and 2004 revealed the renewed presence of PCB-contaminated sediment and water 

within the SCSD drainage system (Ref. 8, p. 11). EPA, MDEQ, MCPWO, and the City of St. Clair Shores 

have coordinated efforts to identify potential source areas and investigate potential migration pathways into or 

out of the SCSD utility corridor. In April 2005, direct-push soil borings were advanced at 13 locations within 

the SCSD utility corridor along Bon Brae Street, Lakeland Boulevard, and Harper Avenue (Ref. 8, pp. 11, 12). 

The highest PCB concentration detected was 100 ppm at a depth of 8 to 8.5 feet below ground surface (bgs) 

(Ref. 8, p. 19). In May 2005, 64 additional direct-push soil borings were advanced at suspected source 

locations within the SCSD utility corridor along Bon Brae Street and Harper Avenue (Ref. 8. p. 12). The 

highest PCB concentration detected was 31,820 ppm at a depth of 0 to 1 feet bgs (Ref. 8, p. 19). 

In 2006, EPA excavated surficial PCB-contaminated soil from several residential properties identified during 

previous investigations (Ref. 5, p. 8). The contaminated areas were excavated to 8 to 12 inches bgs and then 
16 

sampled for PCBs (Refs. 14, p. 3; 15, p. 6). If PCB contamination exceeding the site-specific cleanup goal (4 

ppm) remained, then additional excavation to 2 feet bgs was conducted. Confirmatory soil samples were 

collected after excavation (Refs. 14, p. 3; 15, p. 6). These areas were backfilled, compacted and seeded to 

eliminate any direct contact threat to residents (Refs. 14, p. 3; 15, p.6). Following removal of PCB 

contaminated soil to a depth of 2 feet, PCB contaminated soil still remained at a depth greater than 2 feet bgs at 

some locations (see section 2.2.2 of this HRS documentation record). The PCB-contaminated surficial soil 

(approximately 2-feet bgs) that was excavated from residential properties in 2006 is not considered as part of 

this source area. 

Based on the information presented above, it is thought that the PCBs were allegedly released in the SCSD 

concrete sewer pipes area near Bon Brae Street and Harper Avenue by an unknown entity. The PCBs were 

then transported through the SCSD concrete sewer pipes that discharge into the Lange/Revere Street Canals 

through an outfall. The subsurface soil contamination in the vicinity of SCSD concrete sewer pipes is most 

likely caused by leaky sewer pipes. 

Location of the source, with reference to a map of the site: The contamination in the SCSD concrete sewer 

pipes that are connected to the drain discharging into the Lange Street Canal and Revere Street Canal and the 

contaminated soil surrounding the pipes are considered to be the source. The source area location is shown on 

Figure 1. 

Containment: Releases to surface water through overland migration and/or flood: This source consists of 

contamination in the SCSD sewer pipes and contaminated soil surrounding the SCSD sewer pipes. The Lange 

Street and Revere Street canals, and Lake St. Clair have been contaminated with PCBs detected in the source 

area, therefore, there is evidence of hazardous substance migration from the source. A surface water 

containment factor value of 10 was assigned (Ref. 1, Table 4-2, pp. 51609, 51610). 

2.2.2 Hazardous Substances 

Contamination in the Piping

The presence of PCBs has been documented into the SCSD sewer system that drains to the southeast and 

discharges to the canals (Refs. 6, p. 33; 8, p.11; 15, p. 2). A February 2002 MDEQ/MCPWO study (Ref. 8, p. 

10) and a March 2002 START study (Ref. 6, pp. 32, 33) revealed high levels of PCBs in the sediment in the 

SCSD piping. The highest concentration of PCBs (3,270 ppm) was detected within the SCSD concrete piping 

at the intersection of Harper Avenue and Bon Brae Avenue (Ref. 8, p.10). 

During March 2002 the USEPA Emergency Response Branch launched efforts in support of the MDEQ and 

MCPWO to characterize the nature and extent of PCB contamination in the SCSD utility corridor and the 
 

Lange Street Canals (Ref. 8, p.10). Laboratory analytical results from sediment samples collected by USEPA 

in the SCSD concrete piping indicated the presence of PCBs at a maximum concentration of 121,000 ppm at 

manhole location M4335 near the intersection of Bon Brae Avenue and E Street (Ref. 8, pp. 10, 11). 

While EPA and the County conducted substantial removal and cleaning activities within the piping, as shown 

by the results of the MDEQ SI, PCB impacts from the contamination in the piping remain in the sediments of 

the Lange and Revere Street canals. The removal did not address the substances that already had escaped the 

piping prior to the removal, therefore, PCBs are associated with this portion of Source 1. 

Contamination in the Subsurface Soil 

Analytical results indicate that PCBs were present in 133 soil samples collected from 76 direct-push soil 

boring locations installed during April and May 2005 (Ref. 8, p. 19). On April 4 and 5, 2005, direct-push soil 

borings were advanced by MDEQ at 13 locations next to the SCSD utility corridor along Bon Brae Street, 

Lakeland Boulevard, and Harper Avenue. (Ref. 8, p. 11). The work was performed by MDEQ in accordance 

with the work plan (Ref. 8A, p. 1). In May 2005, 64 additional direct-push soil borings were advanced at 

suspected source locations next to the SCSD utility corridor along Bon Brae Street and Harper Avenue (Ref. 8, 

p.12). The work was performed by Weston Solutions of Michigan for MDEQ in accordance with the work 

plan (Refs. 8, p. 13; 8C). 

Background Level: In order to characterize the soil portion of Source 1 through chemical analysis, soil 

samples collected from soil borings MSB-5 and MSB-6 are considered to represent background contaminant 

levels (Ref. 8, p. 45). Soil boring MSB-5 is located in the northeastern portion of the contaminated soil area 

(Ref. 8, p. 45). Although this sample location is in the area of PCB contamination, this sample location was 

selected as a background sample because the primary contaminants of concern (PCB) were not detected in soil 

samples collected from this location. Soil boring MSB-6 is located at the northern border of the contaminated 

soil area (Ref. 8, p. 45). This location appears to be outside the influence of soil contamination (Ref. 8, p. 45). 

The soil boring location was selected because the primary contaminants of concern (PCBs) were not detected 

in soil samples collected from this location. The soil samples were collected from MSB-5 and MSB-6 at 

similar depths to the contaminated samples. 

Although the HRS does not require that contamination meet observed release criteria to be associated with the 

source, EPA considers that contamination levels that meet the observed release criteria are sufficient to be 

associated with the source. 

17 
- Background Levels at Source 1 – Contaminated soil from unknown source 

Three background soil samples were collected from soil boring MSB-6 from depths ranging from 0.5 to 1, 8.5 

to 9, and 15 to 16 feet bgs (Ref. 8, pp. 107). Five background soil samples were collected from soil boring 

MSB-5 from depths ranging from 0.5 to 1, 3 to 4, 7 to 8, 11 to 11.5 and 15 to 16 feet bgs (Ref. 8, pp. 106) 

TABLE 1 

BACKGROUND SOIL SAMPLES 

PCB (AROCLOR) CONCENTRATIONS 

Sampling 

Location 

Type and 

USCS 

Description 

Depth 

(ft bgs) Date Hazardous 

Substance(s) 

RL 

(μg/kg) 

Concentration 

(μg/kg) References 

Soil; CL 0.5 -1 4/5/2005 Aroclor-1248 110.0 ND Refs. 8, pp. 62, 

106; 10, pp. 1, 

2;8A, p.1 

MSB-5 

Soil; CL 3 -4 4/5/2005 Aroclor-1248 110.0 ND Refs. 8, pp. 62, 

106; 10, pp.1, 

3;8A, p.1 

Soil; CL 7 - 8 4/5/2005 Aroclor-1248 120.0 ND Refs. 8, pp. 62, 

106; 9, pp. 1, 

6;8A, p.1 

Soil; CL 11 ­

11.5 

4/5/2005 Aroclor-1248 110.0 ND Refs. 8, pp. 62, 

106; 13, pp. 1,6 

Soil; CL 15 - 16 4/5/2005 Aroclor-1248 120.0 ND Refs. 8, pp. 62, 

106; 9, pp. 1, 7;8A, 

p.1 

MSB-6 Soil; SP 0.5 -1 4/5/2005 Aroclor-1248 130.0 ND Refs. 8, pp. 62, 63, 

107; 9, p. 8;8A, p.1 

Soil; SW, 

CL 

8.5 -9 4/5/2005 Aroclor-1248 120.0 ND Refs. 8, pp. 62, 63, 

107; 9, p. 9;8A, p.1 

Soil; CL 15 - 16 4/5/2005 Aroclor-1248 120.0 ND Refs. 8, pp. 62, 63, 

107; 9, p. 10;8A, 

p.1 

Notes: 

μg/kg – Microgram per kilogram 

Aroclor-1248 - one PCB congener 

bgs – Below ground surface 

CL – Clay 

ft – Feet 

ND – Non-detect 

PCB – Polychlorinated biphenyl 

RL – Reporting limit is at or above the MDL and is based on a calibration standard at or below the RL. RL is 

determined based on the calculated MDL using the specific reference method, the MDL spiking concentration, 

or a concentration based on these factors and Best Professional Judgment (Ref. 32, pp. 15, 16). 

MDL – Method Detection Limit 

SP – Poorly graded sand 

SW – Well-graded, fine to coarse sand 

USCS – Unified Soil Classification System 

18 
19 

- Source 1 – Contamination in the SCSD concrete sewer pipes and subsurface contaminated soil surrounding 

the pipe area 

It is thought that the PCBs were released in the SCSD sewer pipes area near Bon Brae Street and Harper 

Avenue by an unknown entity. The PCBs were then transported through the SCSD sewer pipes that discharge 

into the Lange Street Canal through an outfall. The subsurface soil contamination in the vicinity of SCSD 

concrete sewer pipes is most likely caused by leaky sewer pipes. The excavated PCB contaminated surficial 

soil (approximately 2-feet bgs) from residential properties in 2006 is not considered as part of this source area. 

During the April 2005 soil boring investigation, PCBs were detected in 21 soil samples collected from 12 

direct-push locations (Ref. 8, p. 19). The MDEQ Environmental Laboratory analyzed the samples using 

Method 8082 (Ref. 9, pp. 1-12; Ref. 10, pp. 1-14; Ref. 11, pp. 1-12; Ref. 12, pp. 1 -11; Ref. 13, pp. 1- 9). 

During the May 2005 soil boring investigation, PCBs were detected in 112 soil samples collected from 64 

direct-push soil boring locations (Ref. 8, p. 19). Envirosystems Laboratory and the MDEQ Environmental 

Laboratory analyzed the samples for PCBs (Ref. 8, pp. 13, 14). Envirosystems Laboratory analyzed the 

samples using CLP SOW OLM04.3, Modification Reference Number 1238.0, Title R5051605 (Ref. 8B, pp. 6, 

30-34, 130, 212, 280, 510, 580, 622, 686). 

 In 2006, EPA excavated surficial PCB-contaminated soil from several residential properties identified during 

previous investigations (Ref. 5, p. 8). The contaminated areas were excavated to 8 to 12 inches bgs and then 

sampled for PCBs (Refs. 14, p. 3; 15, p. 6). If PCB contamination exceeding the site-specific cleanup goal (4 

ppm) remained, then additional excavation to 2 feet bgs was conducted. Confirmatory soil samples were 

collected after excavation (Refs. 14, p. 3; 15, p. 6). These areas were backfilled, compacted and seeded to 

eliminate any direct contact threat to residents (Refs. 14, p. 3; 15, p.6); therefore, soil represented by the 

samples collected from 0 to 2 feet bgs and subsequently removed during the 2006 removal action are not 

included as part of the source area. 
20 

TABLE 2 

CONTAMINATED SOIL SAMPLES 

PCB (AROCLOR) CONCENTRATIONS 

Sampling 

Location

Type and 

USCS 

Description

Depth 

(ft bgs) Date Hazardous Substance 

RL/SQL 

(μg/kg) 

Hazardous 

Substance 

Concentration 

(μg/kg)

References

MSB-1 Soil; SW 8-9 4/4/2005 11,000 100,000 D JD 

Refs. 11, pp. 1, 3, 

12; 8, p. 102; 8A, 

p.1; 8B, p. 837 

MSB-2 Soil; SW 8-8.5 4/4/2005 120 320 JA JD 

Ref. 11, pp. 1, 6, 

12; 8, p. 103 ;8A, 

p.1; 8B, p. 837 

MSB-3 Soil; CL, 

SW 12-13 4/4/2005 120 160 JD 

Refs. 11, pp. 1, 

11, 12;8, p. 

104;8A, p.1; 8B, 

p. 837 

MSB-7 Soil; CL 4-4.5 4/5/2005 2,300 19,000 D 

Refs. 10, pp. 1, 4, 

14; 8, p.108;8A, 

p.1; 8B, p. 835 

3.5-3.8 4/5/2005 1,100 5,000 D 

Refs. 10, pp. 1, 5, 

14; 8, p.110; 8A, 

p.1; 8B, p. 835 

MSB-9 Soil; S, CL 

3.8-4 4/5/2005 120 310 JD JA 

Refs. 10, pp. 1, 6, 

14; 8, p.110;8A, 

p.1; 8B, p. 835 

3-4 4/5/2005 2,400 24,000 D JA 

Refs. 10, pp. 1, 9, 

14; 8, p.111;8A, 

MSB-10 Soil; CL p.1; 8B, p. 835 

4-4.5 4/5/2005 2,700 13,000 D JA 

Refs. 10, pp. 1, 

10, 14; 8, 

p.111;8A, p.1; 

8B, p. 835 

5-5.5 4/5/2005 6,000 27,000 D, JD 

Refs. 10, pp. 1, 

12, 14; 8, 

p.113;8A, p.1; 

8B, p. 836 

MSB-12 Soil; CL 

8-8.5 4/5/2005 6,100 52,000 D JD 

Refs. 10, pp. 1, 

13, 14; 8, 

p.113;8A, p.1; 

8B, p. 836 

10-10.5 4/5/2005 110 180 JD 

Refs. 12, pp. 1, 4, 

11; 8, p.111;8A, 

p.1; 8B, p. 839 

MSB-10 Soil; CL 

13-13.5 4/5/2005 

Aroclor1248 

640 3,100 D JA 

Refs. 12, pp. 1, 5, 

11; 8, p.111;8A, 

p.1; 8B, p. 839 
21 

Sampling 

Location

Type and 

USCS 

Description

Depth 

(ft bgs) Date Hazardous Substance 

RL/SQL 

(μg/kg) 

Hazardous 

Substance 

Concentration 

(μg/kg)

References

SCS-001/ 

E0O39DL SC 4.5-9 5/17/05 200 2,100 DL 

Refs. 8B, pp. 5-

10, 15, 23, 62, 

74-77; 8, 

p.137;8C, 18, 24-

31 

SCS-001/ 

E0O40DL CL 9-12 5/17/05 85,000 990,000 DL 

Refs. 8B, pp. 5-

10, 16, 23, 64, 

74-77;8, 

p.137;8C, 18, 24-

31 

SCS-002/ 

E0O51 SC 6-9 5/17/09 37 450 

Refs. 8B, pp. 

509-514, 515, 

525, 541, 570-

574; 8, p.138;8C, 

18, 24-31 

SCS-003/ 

E0O56 SC 9-12 5/17/09 39 76 

Refs. 8B, pp. 

509-514, 517, 

525, 552, 570-

574; 8, p.139;8C, 

18, 24-31 

SCS-005/ 

E0O29DL SP 6-9 5/17/09 450 4,000 DL 

Refs. 8B, pp. 5-

10, 12, 21, 47, 

74-77; 8, 

p.141;8C, 18, 24-

31 

SCS-005/ 

E0O30DL SP 9-12 5/17/09 200 2,400 DL 

Refs. 8B, pp. 5-

10, 13, 21, 49, 

74-77; 8, 

p.141;8C, 18, 24-

31 

SCS-005/ 

E0O28DL SP 12-15 5/17/09 400 2,800 DL 

Refs. 8B, pp. 5-

10, 12, 21, 45, 

74-77; 8, 

p.141;8C, 18, 24-

31 

SCS-006/ 

E0O62 CL 9-12 5/17/09 34 47 

Refs. 8B, pp. 

509-514, 519, 

527, 559, 570-

574; 8, p.142;8C, 

18, 24-31 

SCS-007/ 

E0O66 CL 6-9 5/18/09 

Aroclor1248 

34 95 

Refs. 8B, pp. 

509-514, 520, 

527, 566, 570-

574; 8, p.143;8C, 

18, 24-31 
22 

Sampling 

Location

Type and 

USCS 

Description

Depth 

(ft bgs) Date Hazardous Substance 

RL/SQL 

(μg/kg) 

Hazardous 

Substance 

Concentration 

(μg/kg)

References

SCS-014/ 

E0O79 SP/CL 11.5-13 5/18/09 39 120 

Refs. 8B, pp. 5-

10, 17, 25, 69, 

74-77; 8, 

p.150;8C, 18, 24-

31 

SCS-023/ 

E0OC1DL SP 9-12 5/19/09 3,900 22,000 DL 

Refs. 8B, pp. 

211-216, 221, 

229, 267, 272-

274; 8, p. 

159;8C, 18, 24-

31 

SCS-024/ 

E0OC4DL CL 9-12 5/19/09 370 3,700 DL 

Refs. 8B, pp. 

579-585, 586, 

595, 608, 609, 

611; 8, p.160;8C, 

18, 24-31 

SCS-025/ 

E0OC9DL SP 4-6 5/20/09 350 3,800 DL 

Refs. 8B, pp. 

129-134, 137, 

162, 190, 196-

198; 8, p. 

161;8C, 18, 24-

31 

SCS-025/ 

E0OD0D

L 

SP 6-9 5/20/09 770 6,800 DL 

Refs. 8B, pp. 

129-134, 137, 

162, 192, 196-

198; 8, p. 

161;8C, 18, 24-

31 

SCS-025/ 

E0OC6DL SP 12-15 5/20/09 38,000 110,000 DL 

Refs. 8B, pp. 

129-134, 136, 

162, 184, 196-

198; 8, p. 

161;8C, 18, 24-

31 

SCS-025/ 

E0OC7DL CL 15-16 5/20/09 210,000 1,500,000 DL 

Refs. 8B, pp. 

129-134, 136, 

162, 186, 196-

198; 8, p. 

161;8C, 18, 24-

31 

SCS-026/ 

E0OD3 SP 5-6 5/20/09 

Aroclor1248 

35 530 

Refs. 8B, pp. 

579-585, 587, 

596, 608, 609, 

616; 8, p.162;8C, 

18, 24-31 
23 

Sampling 

Location

Type and 

USCS 

Description

Depth 

(ft bgs) Date Hazardous Substance 

RL/SQL 

(μg/kg) 

Hazardous 

Substance 

Concentration 

(μg/kg)

References

SCS-026/ 

E0OD4D

L 

SP 7.5-9 5/20/09 100 950 DL 

Refs. 8B, pp. 

129-134, 138, 

162, 195, 196-

198; 8, p. 

162;8C, 18, 24-

31 

SCS-027/ 

E0OG4 CL 12-15 5/24/09 38 193 

Refs. 8B, pp. 

630, 621-628, 

639, 659, 678-

681; 8, p. 

163;8C, 18, 24-

31 

SCS-035/ 

E0O85 CL 4-5 5/18/09 41 78 

Refs. 8B, pp. 

296, 334, 346-

349, 278-284; 8, 

p.120;8C, 18, 24-

31 

SCS-040/ 

E0OD8 SP 9-9.5 5/19/09 39 110 

Refs. 8B, pp. 

302, 318-321, 

579-585, 588, 

597; 8, p. 

125;8C, 18, 24-

31 

SCS-041/ 

E0OD9D

L 

SP/CL 4-8 5/20/09 410 3,300 DL 

Refs. 8B, pp. 

304, 318-321, 

579-585, 588, 

597; 8, p. 

126;8C, 18, 24-

31 

SCS-061/ 

E0OG3D

L 

CL 9-12 5/24/09 7,800 31,000 DL 

Refs. 8B, pp. 

630, 621-628, 

638, 658, 678-

681; 8, p. 

167;8C, 18, 24-

31 

SCS-063/ 

E0OG9D

L 

CL 12-15 5/24/09 390 3,200 DL 

Refs. 8B, pp. 

631, 621-628, 

638, 666, 678-

681; 8, p. 

169;8C, 18, 24-

31 

SCS-078/ 

E0OL0DL CL 6-9 5/25/09 

Aroclor1248 

830 6,500 DL 

Refs. 8B, pp. 

684-692, 700, 

708, 757; 8, p. 

183;8C, 18, 24-

31 
24 

Sampling 

Location

Type and 

USCS 

Description

Depth 

(ft bgs) Date Hazardous Substance 

RL/SQL 

(μg/kg) 

Hazardous 

Substance 

Concentration 

(μg/kg)

References

SCS-078/ 

E0OL1DL CL 9-12 5/25/09 200 2,400 DL 

Refs. 8B, pp. 

684-692, 701, 

708, 761; 8, p. 

183;8C, 18, 24-

31 

SCS-078/ 

E0OK8D

L 

SP 12-15 5/25/09 

Aroclor1248 

800 6,300 DL 

Refs. 8B, pp. 

684-692, 699, 

708, 754; 8, p. 

183;8C, 18, 24-

31 

Notes: 

μg/kg – Microgram per kilogram 

bgs – Below ground surface 

CL – Clay 

D – Analyte value quantified from dilution(s); reporting limit raised 

ft – Feet 

JA – Result considered estimated because multiple Aroclors present 

JD – Because of severe degradation, specific Aroclor identification difficult and quantitation estimated 

PCB – Polychlorinated biphenyl 

RL – Reporting limit is at or above the MDL and is based on a calibration standard at or below the RL. RL is 

determined based on the calculated MDL using the specific reference method, the MDL spiking concentration, 

or a concentration based on these factors and Best Professional Judgment (Ref. 32, pp. 15, 16). RL is 

applicable to samples analyzed by MDEQ laboratory (April 2005 borings). 

MDL – Method Detection Limit 

S – Sand 

SC – Clayey sands, sand-silt mixtures 

SP– Poorly graded sand 

SQL – Sample Quantitation Limit, the SQL was derived from the non-detected Aroclors from the respective 

samples. SQL is applicable to the samples analyzed by CLP laboratory (May 2005 borings). 

SW– Well-graded, fine to coarse sand 

USCS – Unified Soil Classification System 

The qualified data (JA and JD) are useable for source characterization, because while the identification of the 

exact Aroclor mix or the specific PCB congener may have been difficult in the qualified samples (based on 

type of J qualifier), these factors do not raise any question regarding presence of the PCBs in the samples. 

The MDEQ background and source soil samples collected in April 2005 were similar because the samples: (1) 

were most likely collected using the same equipment and procedures by the same individuals (Appendix A of 

Reference 8, pp. 102-114); (2) were collected within the same time frame (4th April 2005 and 5th April 2005) 

and therefore, the same weather conditions (Ref. 8, pp. 59-66); (3) were analyzed using the same methods as 

documented in References 9 through 13; and (4) were collected from similar soil types and similar depths as 

documented in Tables 1 and 2 of this documentation record. 
25 

The WESTON source soil samples collected in May 2005 were similar because the samples: (1) were collected 

using similar procedures (Ref. 8, p. 13, Appendix A); (2) were collected within the same time frame (May 17-

25, 2005) (Ref. 8, p. 12); and (3) were collected from similar soil types and similar depths as documented in 

Tables 1 and 2 of this documentation record. 

HAZARDOUS WASTE QUANTITY 

2.4.2.1 Source Hazardous Waste Quantity 

2.4.2.1.1 Hazardous Constituent Quantity (Tier A) 

The information available is not sufficient to adequately determine Tier A as required in Section 2.4.2.1.1 of 

the HRS. As a result, the evaluation of the source hazardous waste quantity proceeds to the evaluation of Tier 

B, hazardous waste stream quantity (Ref. 1, Section 2.4.2.1.1, pp. 51590-51591). 

2.4.2.1.2 Hazardous Wastestream Quantity (Tier B) 

The information available is not sufficient to adequately determine Tier B as required in Section 2.4.2.1.2 of 

the HRS. As a result, the evaluation of the source hazardous waste quantity proceeds to the evaluation of Tier 

C, volume (Ref. 1, Section 2.4.2.1.2, p. 51591). 

2.4.2.1.3 Volume (Tier C) 

 Since the hazardous waste quantity was not adequately determined under Tier A or B, the volume will be 

evaluated under Tier C. For the migration pathways, the source is assigned a value for volume using the 

appropriate Tier equation from Table 2-5 (Ref. 1, Section 2.4.2.1.3). The equation for source type “other” is 

V/2.5, where V is expressed in cubic yards. It is not known how much PCB-containing material was 

originally spilled or discharged into the SCSD storm sewer system, nor is it known how much PCBcontaminated soil surrounds the piping. Despite the removal action, some quantity is present in the piping and 

in the surrounding soil, and some quantity has reached the Lange and Revere Street Canals. For Source 1, a 

value of greater than zero but an amount unknown was assigned for the hazardous waste quantity value for 

volume (Tier C). (Ref. 1, Section 2.4.2.1.3, Table 2-6, p. 51591). 

2.4.2.1.4 Area (Tier D) 

Area, Tier D, is not applicable for source type “other” (Ref. 1, Table 2-5). 

2.4.2.1.5 Calculation of Source Hazardous Waste Quantity Value 

As described in the HRS rule, the highest value assigned to a source from among the four tiers of hazardous 

waste quantity – constituent quantity (Tier A), wastestream quantity (Tier B), volume (Tier C), or area (Tier D) 
26 

– shall be selected as the source hazardous waste quantity value (Ref. 1, Table 2-6, p. 51591). As summarized 

in Table 3 below, Source 1 has a source hazardous waste quantity value of greater than zero. Table 4 below 

summarizes the source description. 

TABLE 3 

SOURCE 1-- HAZARDOUS WASTE QUANTITY VALUE

Tier Measure Source Value 

Tier A, Hazardous Constituent Quantity Not Evaluated 

Tier B, Hazardous Wastestream Quantity Not Evaluated 

Tier C, Volume >0 

Tier D, Area 0 

Notes: 

 >-- greater than

TABLE 4 

SUMMARY OF SOURCE DESCRIPTION

Containment Factor Value by Pathway 

SW Air 

Source 

No. 

Source 

Hazardous 

Waste 

Quantity 

Value 

Source 

Hazardous 

Constituent 

Quantity 

Complete 

(Y/N) 

GW 

(Table

3-2) Overland/Flood 

(Table 4-2) 

GW to SW 

(Table 3-2) 

Gas (Table 

6-3) 

Particulate 

(Table 6-9) 

1 >0 N NS 10 NS NS NS 

Notes: 

>-- greater than 

GW – Ground water 

HRS – Hazard Ranking System 

NS – Not scored 

SW – Surface water 

The Source Hazardous Waste Quantity Value for the SCSD Site therefore is greater than 0. 
27 

4.0 SURFACE WATER MIGRATION PATHWAY 

The surface water pathway includes the overland flow and flood migration component and the ground waterto-surface water component. The overland flow and flood migration component has been evaluated as part of 

this HRS documentation record. 

4.1 OVERLAND AND FLOOD MIGRATION COMPONENT 

This section describes the overland and flood migration component of the surface water pathway. 

4.1.1.1 Definition of Hazardous Substance Migration Path for Overland/Flood Migration 

The presence of PCBs has been documented in the SCSD sewer system that drains to the southeast and 

discharges to the Lange and Revere Street canals (Refs. 6, p. 33; 8, p. 11; 15, p. 2). The canals are connected 

to Lake St. Clair (Ref. 16). The probable point of entry (PPE) to surface water is the point where the SCSD 

sewer system discharges into the canals. This is the beginning of the in-water segment of the surface water 

migration pathway (Ref. 16). PCB contamination is present in the source area at the site (see section 2.2.2 of 

this HRS documentation record). PCB contamination also is present in the Lange Street and Revere Street 

canals (Ref.5, p. 6). PCB contamination was detected in samples collected from the Lange Street and Revere 

Street canals, and Lake St. Clair (Ref. 5, p. 6). The hazardous substance migration path consists of the Lange 

and Revere Street canals, Lake St. Clair, and the Detroit River in-water segment (Ref. 16). 

4.1.1.2 Target Distance Limit 

The 15-mile target distance limit (TDL) begins at the SCSD outfall where the drain discharges into the canals, 

which in turn discharge to Lake St. Clair; the TDL continues along the Detroit River. The TDL is documented 

in Reference 16. 

4.1.2 Drinking Water Threat 

4.1.2.1 Likelihood of Release

Numerous investigations have been conducted to determine the extent of contamination. Historical 

information and analytical data from the recent investigations are used to document an observed release to 

surface water through chemical analysis. 

4.1.2.1.1 Observed Release 

Direct Observation: 

An observed release through direct observation to the surface water migration pathway has not been 

established at the site. 
28 

Chemical Analysis: 

An observed release to the surface water pathway has been established at the SCSD Site through chemical 

analysis. The observed release is based on the detection of PCBs in sediment samples collected from the 

canals and Lake St. Clair. In July 2008, 44 sediment samples, including 1 upgradient background sample and 

4 duplicate samples, 2 equipment blank samples, and 2 field blank samples, were collected (Ref. 5, pp. 13, 14). 

Sediment samples were collected from 0 to 33 inches below the sediment-water interface (Ref. 5, pp. 31-40). 

The samples were analyzed for PCBs by CompuChem- Liberty Analytical Corporation in accordance with the 

Contract Laboratory Program (CLP) Statement of Work (SOW) SOM01.2 (8/2007) (Ref. 5, pp. 15, 76, 145, 

253). If the background concentration is not detected (or is less than the detection limit), an observed release is 

established when the sample measurement equals or exceeds the sample quantitation limit. (Ref. 1, Table 2-3, 

p. 51589). Figure 4 of Reference 5 shows the sediment sampling locations, and Table 2 of Reference 5 

describes the sediment samples (Refs. 5, pp. 27, 31-40; 17A, pp. 1-30). The sample descriptions are also 

presented in Table 5 below (Refs. 5, pp. 31 – 40; 17A, pp. 1-30). 
29 

TABLE 5 

SEDIMENT SAMPLE DESCRIPTIONS 

SAINT CLAIR SHORES DRAIN SITE 

(Ref. 5, pp. 31-40; 17A, pp. 1-30) 

SAMPLE 

NUMBER 

DEPTH OF 

WATER AT 

SAMPLE 

LOCATION 

UNIT 

THICKNESS

LITHOLOGICAL 

DESCRIPTION 

SAMPLE 

INTERVALS AND 

COMMENTS 

SD1 8ft 0-2 in. Wet, dark gray, fine to coarse 

sand with silt, gravel, some 

organic plant matter, and shell 

fragments. 

SD1 sample collected 

from 0-9 in. 

 2-9 in. Moist, grayish brown clay with 

some silt. 

 

SD2 7 ft. 0-2 in. Wet, blackish gray silt with some 

fine sand and clay. 

SD2 sample collected 

from 0-8 in. 

 2-7 in. 

7-15 in. 

Very moist, gray, loose, silt and 

clay. 

Moist gray silty clay with trace 

sand, loose. 

 

SD3 8.5 ft. 0-4 in. Wet, dark blackish gray, loose 

silt with some fine sand. 

SD3 sample collected 

from 0-10 in. 

 4-10 in. Very moist, dark gray, silty fine 

sand with some clay. 

 

SD5 9 ft. 0-13 in. Very moist, blackish gray, loose 

silt with some fine sand and clay. 

SD5 sample collected 

from 0-8 in. 

SD6 6 ft. 0-6 in. Wet, dark gray, loose, silty, fine 

sand. 

SD6 sample collected 

from 0-10 in. 

 6-10 in. Very moist, grayish brown, 

loose, silty clay. 

 

SD7 7 ft. 0-4 in. Wet, blackish gray, fine sand 

with some silt and organic 

matter. 

SD7 sample collected 

from 0-9 in. 

 4-18 in. Wet, greenish brown, fine to 

medium sand with some silt and 

trace gravel. 

 
30 

SAMPLE 

NUMBER 

DEPTH OF 

WATER AT 

SAMPLE 

LOCATION 

UNIT 

THICKNESS

LITHOLOGICAL 

DESCRIPTION 

SAMPLE 

INTERVALS AND 

COMMENTS 

SD16 8.5 ft. 0-2 in. Wet, greenish gray, fine to 

medium sand with trace silt and 

plant matter and soil fragments. 

SD16 sample collected 

from 0-10 in. 

 10-16 in. Moist, grayish brown, clay with 

some silt. 

 

SD19 8 ft. 0-1 in. Wet, greenish gray, fine to 

medium sand with trace plant 

material and silt 

SD19 sample collected 

from 0-6 in. 

 10-16 in. Moist, variegated - grayish 

brown/greenish gray, clayey silt. 

 

SD20 6 ft. 0-2 in. 

3-11 

Wet, greenish gray, medium sand 

with trace silt. 

Moist, greenish gray, clay 

SD20 sample collected 

from 0-7 in. 

SD26 8.5 ft. 0-2 in. Wet, greenish gray, silty fine 

sand with organic matter. 

SD26 sample collected 

from 0-7 in. 

 2-4 in. Wet, dark gray, fine sand with 

some silt and organic matter and 

shell fragments. 

 

 4-10 in. Very moist, brownish gray, 

clayey fine sand. 

 

SD27 6 ft. 0-15 in. Wet, greenish gray, fine to 

medium sand with trace silt some 

root matter in top couple of 

inches. 

SD27 sample collected 

from 0-8 in. 

SD29 10 ft. 0-0.5 in. Wet, gray silt and fine to 

medium sand with trace organic 

root material and shell 

fragments.. 

SD29 sample collected 

from 0-7 in. 

0.5-7 in. Moist, grayish brown clay with 

some silt. 

Background Sediment Samples

The Lange Street Canal and Revere Street Canal are contiguous to Lake Saint Clair, and the SCSD outfall 

drain is located upstream of the canals. Sediment samples SD1, SD16, SD19, SD20, SD27 and SD29 

collected from Lake St. Clair are identified to represent background levels. SD16, SD19, SD20, SD27 and 

SD29 were collected closer to the canals. These samples were selected as background samples because PCBs 

were not detected in these samples. Non detection of PCBs in these samples suggests that the PCBs are not 

widespread in this portion of Lake St. Clair. The locations of the background sediment samples SD20 and 
31 

SD27 are very close to canals and appear to be within the zone of sediment deposition from other nearby 

canals (Ref. 5, pp. 27). Table 6 below summarizes the analytical results for background sediment samples 

SD1, SD16, SD19, SD20, SD27, and SD29. 

TABLE 6 

BACKGROUND SAMPLES 

PCB (AROCLOR) CONCENTRATIONS 

Sample No. Hazardous 

Substance 

Concentration 

(μg/kg) 

Q SQL 

(μg/kg) 

Sampling 

Date 

References 

SD1/E2955 Aroclor-1248 39 U 39 7/29/2008 Refs. 5, pp. 44, 76-82, 

88-92, 115; 17A, p. 1) 

SD27/E2981RE Aroclor-1248 41 U 41 7/29/2008 Refs. 5, pp. 53, 261, 

269, 251-258, 324; 

17A, p. 27) 

SD29/E2983 Aroclor-1248 38 U 38 7/29/2008 Refs. 5, pp.54, 262, 

269, 251-258, 326; 

17A, p. 29) 

SD16/E2970 Aroclor-1248 41 U 41 7/29/2008 Refs. 5, pp. 49, 76-81, 

86, 88-92, 138; 17A, p. 

16) 

SD19/E2973 Aroclor-1248 38 U 38 7/29/2008 Refs. 5, pp. 50, 76-81, 

86, 88-92, 141; 17A, p. 

19) 

SD20/E2974 Aroclor-1248 39 U 39 7/29/2008 Refs. 5, pp. 50, 76-81, 

87-92, 142; 17A. 20) 

Notes: 

μg/kg - Microgram per kilogram 

PCB - Polychlorinated biphenyl 

Q - Laboratory data qualifier 

SD - Sediment sample 

SQL – Sample Quantitation Limit, the SQL was derived from the non-detected Aroclors from the respective 

samples. 

U - Not detected 

PCB Contaminated Sediment Samples

PCBs were detected above background sample levels in sediment samples collected from the canals and Lake 

St. Clair. Observed release through chemical analysis has been documented because PCBs were not detected 

at or above the detection limit in the background sediment samples and the concentrations of PCBs in the 

release sediment samples were above the detection limits. Furthermore sediment sample SD26 was collected 

close to the Lange Street and Revere Street canals (see Figure 4 of this HRS documentation record). Table 7 
32 

below summarizes the PCB concentrations detected above the reference criteria in the investigative sediment 

samples. 

TABLE 7 

SEDIMENT RELEASE SAMPLES 

PCB (AROCLOR) CONCENTRATIONS 

Sample No. Hazardous 

Substance 

Concentration 

(μg/kg) 

Q SQL 

(μg/kg)

Sampling 

Date 

References 

SD2/E2956DL 

(Lange Street 

Canal) 

Aroclor-1248 6,800 DL 940 7/30/2008 Refs. 5, p. 43, 75-80, 

81, 83, 90, 122, 143; 

17, p. 1; 17 A, p. 2 

SD3/E2957DL 

(Lange Street 

Canal) 

Aroclor-1248 1,500 DL 290 7/30/2008 Refs. 5, p. 43, 75-80, 

83, 90, 124, 143 ; 17, 

p. 1; 17 A, p. 3 

SD5/E2959DL 

(Revere Street 

Canal) 

Aroclor-1248 2,800 DL 420 7/30/2008 Refs. 5, p. 44, 75-80, 

84, 90, 127, 143; 17, 

p. 1; 17 A, p. 5 

SD6/E2960 

(Revere Street 

Canal) 

Aroclor-1248 260 65 7/30/2008 Refs. 5, p. 44, 75-80, 

84, 90, 128, 143; 17, 

p. 1; 17 A, p. 6 

SD7/E2961 

(Revere Street 

Canal) 

Aroclor-1248 140 45 7/30/2008 Refs. 5, p. 45, 75-80, 

84, 90, 129, 143; 17, 

p. 1; 17 A, p. 7 

SD26/E2980RE 

(Lake Saint 

Clair) 

Aroclor-1248 41 39 7/29/2008 Refs. 5, p. 260, 252-

258, 268, 321; 17, p.1; 

17 A, p. 26 

Notes: 

μg/kg - Microgram per kilogram 

DL - Sample or extract reanalyzed at higher dilution factor because the concentration of the analyte exceeded 

upper calibration range. The sample concentrations are for reanalyzed sample. 

PCB - Polychlorinated biphenyl 

Q - Laboratory data qualifier 

SD - Sediment sample 

SQL – Sample Quantitation Limit, the SQL was derived from the non-detected Aroclors from the respective 

samples. 

The background and the release sediment samples were similar because the samples: (1) were collected using 

the same equipment and procedures as is documented in Reference 17 A; (2) were collected within the same 

time frame (29 and 30 April 2005) and therefore, the same weather conditions (Ref. 17A, pp. 1-30 ); (3) were 

collected within the canals contiguous with Lake St. Clair and within Lake St. Clair (Refer to Figure 4 of this 

HRS documentation package); (4) were analyzed using the same methods as documented in Appendix E of 

Reference 5; and (5) were collected from similar depths (Refer to Table 4 of this HRS documentation record). 

In accordance with the HRS, if an observed release can be established for a watershed, an observed release 

factor value of 550 should be assigned to that watershed (Ref. 1, p. 51609). 
33 

Observed Release Factor Value: 550 

Attribution

The sediment samples collected from the SCSD sewer pipes in 2002 were found to contain PCBs at high 

concentrations at the intersection of Harper Avenue and Bon Brae Street (Ref. 8, p. 11). This suggested that 

the PCBs were allegedly disposed of in the SCSD sewer pipes area near Bon Brae Street and Harper Avenue 

by an unknown entity. The PCB contamination has also been detected in the Lange Street and Revere Street 

canals and Lake Saint Clair (Refs. 5, p. 16; 7, p. 9, 37). Because their discharge point is on the canals, the 

SCSD sewer pipes carried and discharged the PCBs into the Lange Street and Revere Street canals causing 

sediment contamination. The Lange Street and Revere Street canals are contiguous to Lake Saint Clair. The 

PCB contamination was then carried from the Lange Street and Revere Street canals into Lake Saint Clair. 

This transport mechanism has contaminated sediments in the Lake Saint Clair. Therefore, the PCBs detected 

in the Lange Street Canal, Revere Street Canal and Lake Saint Clair are attributable to Source 1 because the 

PCBs released in the SCSD sewer pipes were carried to the outfall that discharged into the Lange Street and 

Revere Street Canals and Lake Saint Clair. Furthermore, sediment sample SD26 was collected from close 

proximity to Lange Street Canal and Revere Street Canal. Since SD26 is very close to the Lange Street and 

Revere Street canals and is probably within the sediment deposition area of these canals the contamination 

detected in SD26 is most likely from Lange/Revere Street canals. Furthermore, the location of background 

samples SD19, SD20, SD27, and SD29 around the release sample SD26 effectively serve to isolate the portion 

of the lake under the site’s influence indicating that the impact to Lake St. Clair in SD26 has come from the 

SCSD source and not from other offsite source(s) of contamination. 

 

4.1.2.1.2 Potential to Release 

4.1.2.1.2.1 Potential to Release by Overland Flow 

Because an observed release has been documented through chemical analysis (Section 4.1.2.1.1 of this HRS 

documentation record), the potential to release by overland flow has not been scored (Ref. 1, Section 

4.1.2.1.1). 

 Potential to Release by Overland Flow: NS 

4.1.2.2 Drinking Water Threat – Waste Characteristics 

4.1.2.2.1 Toxicity/Persistence 

Table 8 below provides Drinking Water Threat Waste Characteristics Factor Values for analytes present in the 

source at the SCSD Site (see Sections 2.2.2 and 4.1.2.1.1 of this HRS documentation record). 
34 

TABLE 8 

DRINKING WATER THREAT WASTE CHARACTERISTICS FACTOR VALUES

Hazardous 

Substance

Source 

No.

Toxicity 

Factor 

Value

Persistence 

Factor 

Value*

Toxicity/ 

Persistence/ 

Factor Value 

(Table 4-12)

References

PCBs 1 10,000 1.0 10,000 Ref. 1, Table 4-12; 

Ref. 2, p. BI-10 

Note: 

*Persistence value assigned based on rivers, oceans, coastal tidal waters and Great Lakes (Note: Lake St. Clair 

is located between lakes Huron and Erie; Lake St. Clair is the smallest lake in the Great Lakes system) (Ref. 

33, p. 1). 

The hazardous substances with the highest toxicity/persistence factor value are PCBs. 

Toxicity/Persistence Factor Value: 10,000 

4.1.2.2.2 Hazardous Waste Quantity 

Table 9 below summarizes the source hazardous waste quantity value. 

TABLE 9 

DRINKING WATER THREAT WASTE CHARACTERISTICS FACTOR VALUES

Source 

No.

Source Hazardous Waste 

Quantity Value 

(HRS Rule Section 2.4.2.1.5)

Is Source Hazardous 

Constituent Quantity Data 

Complete? (Y/N) 

1 >0 N 

Source : >0 

According to Section 2.4.2.2 of the HRS, a minimum pathway hazardous waste quantity factor value of 100 

was assigned based on that the hazardous constituent quantity is not adequately determined, and based on the 

Level II concentrations in the surface migration pathway (Section 2.4.2.2). 

Hazardous Waste Quantity Factor Value: 100 

4.1.2.2.3 Waste Characteristics Factor Category Value 

The waste characteristics factor category value was assigned based on the waste characteristics product. The 

waste characteristics product is the product of the toxicity/persistence factor value and the hazardous waste 

quantity factor value (Ref. 1, Section 4.1.2.2.3). Values from the substance with the highest 

toxicity/persistence factor value for the watershed (PCBs) were used (Ref. 1, Section 4.1.2.2.3). 

A hazardous waste quantity factor value of 100 was assigned as described above (Ref. 1, Section 2.4.2.2). 
Toxicity/Persistence Factor Value: 10,000 

Hazardous Waste Quantity Factor Value: 100 

(Toxicity/Persistence x Hazardous Waste Quantity): 

10,000 × 100 = 1.0 × 106 

(subject to a maximum product of 1 × 108) (Ref. 1, Section 4.1.2.2.3, p. 51613) 

A waste characteristics product value of 1.0 × 106

 receives a waste characteristics factor category value of 32 

(Ref. 1, Section 2.4.3.1, Table 2-7). 

Waste Characteristics Factor Category Value: 32 

4.1.2.3 Drinking Water Threat Targets 

4.1.2.3.1 Nearest Intake 

Analysis of sediment samples from Lake St. Clair indicate that PCB concentrations have met the observed 

release criteria (see Section 4.1.2.1.1 of this HRS documentation record). The observed release of PCBs 

establishes a zone of actual Level II contamination. Drinking water intakes are not subject to actual 

contamination because they are located outside the zone of actual contamination; therefore, based on available 

information, these drinking water intakes are not affected by actual contamination. The nearest drinking water 

intake is located approximately 5.68 miles from the PPE and is not subject to actual contamination. Lake St. 

Clair is located between lakes Huron and Erie; Lake St. Clair is the smallest lake in the Great Lakes system 

(Ref. 33, p. 1). The depth of Lake St. Clair is greater than 20 feet and less than 200 feet (Ref. 24, p. 8) The 

dilution weight for Lake St. Clair from Ref. 1, Table 4-13, is 0.00001 (modest depth ocean zone or Great 

Lakes). In accordance with Ref.1, Section 4.1.2.3.1, by multiplying the dilution weight (0.00001) by 20, a 

factor value of 0.0002 was calculated. The product was rounded to the nearest integer and a factor value of 1 

was assigned for the nearest intake (Ref. 1, Section 4.1.2.3.1). 

4.1.2.3.2 Population 

4.1.2.3.2.2 Level I Concentrations 

Level I concentrations have not been established based on the samples collected. 

4.1.2.3.2.3 Level II Concentrations 

No drinking water intake located within the in-water segment has met the Level II actual contamination 

criteria. 

35 
4.1.2.3.2.4 Potential Contamination 

Within the 15-mile TDL two drinking water intakes are located in Lake St. Clair, and one intake is located at 

the mouth of the Detroit River (Ref. 5, p.18). The intakes are denoted on the 15-mile TDL map (Ref. 16, p. 1). 

The City of Mount Clemens and Gross Pointe/Highland Park operate the intakes on Lake St. Clair (Refs. 5, p. 

18; 25, p.1; 27, p.1; 29, p. 1). The populations served by the City of Mount Clemens and Gross 

Point/Highland Park intakes have not been included because they would have no effect on the potential factor 

value. 

The Detroit Water and Sewerage Department operates three intakes, one at the mouth of the Detroit River 

(Water Works Park intake), one approximately 30 miles downstream of the mouth of the Detroit River 

(Southwest intake), and one in Lake Huron (Lake Huron intake) (Ref. 31, p. 1). The water from Water Works 

Park intake is supplied to three water treatment plants: Water Works Park Water Treatment Plant, Spring 

Wells Water Treatment Plant and Northeast Water Treatment Plant (Ref. 31, p.1). The water from Southwest 

intake is supplied to Southwest Water Treatment Plant and water from Lake Huron intake is supplied to Lake 

Huron Water Treatment Plant (Ref. 31, p.1). All five water treatment plants are interconnected so that it would 

allow distribution of water to customers throughout the system (Ref. 31, pp. 1, 2). However, the water 

distribution system piping is connected such that water from one system can be supplied to another system 

during emergency and periods of high demand (Ref. 31, p. 2). In the last 24 years water has never been 

exchanged between the three intakes (Ref. 31, p. 2). The Water Works Park intake lies within the 15-mile 

TDL (Ref. 16, p. 1). The City of Detroit serves approximately 3.5 million people (Ref. 31, p. 1). Based on the 

production rates the Water Works Park intake provides approximately 63 percent of the water (Ref. 31, p. 1). 

Based on the Water Works Park intake providing 63 percent of the water required, the intake serves 

approximately 2,205,000 people (Ref. 30, p. 1,2). Since the Water Works Park intake appears to be located 

closer to the Lake St. Clair (Ref. 16) and the zone of influence of the intake could extend to Lake St. Clair, the 

dilution weight for Lake St. Clair is used. The depth of Lake St. Clair is greater than 20 feet and less than 200 

feet (Ref. 24, p. 8). Using Table 4-14 from the HRS, the value for the moderate ocean zone or Great Lakes 

(depth 20 to 200 feet), and the population of 2,205,000, a dilution-weighted population value of 16 was 

assigned (Ref. 1, Section 4.1.2.3.2.4). This value (16) was divided by 10, rounded to the nearest integer, and 

assigned as the potential contamination factor for the watershed (Ref. 1, Section 4.1.2.3.2.4). 

Potential Contamination Factor: 2 

4.1.2.3.5 Calculation of Population Factor Value 

The population factor value is equal to 2 as calculated below. 

Level I Concentrations (0) + Level II Concentrations (0) + Potential Contamination (2) = 2 

36 
 

4.1.2.3.3 Resources 

Industries that are supplied by the Detroit water system include breweries, the automobile industry, and steel 

mills (Ref. 31, p. 2). Since water from the Detroit water intake within the 15-mile TDL is used for commercial 

food preparation, therefore, in accordance with the HRS Section 4.1.2.3.3 a Resource Factor Value of 5 is 

assigned. 

Resource Factor Value: 5 

4.1.2.3.4 Calculation of Drinking Water Threat - Targets Factor Category Value 

The Drinking Water Threat - Targets Factor Category Value was calculated by summing the nearest intake (1) 

and population (2), and resource (5) factor values for the watershed as summarized below (Ref. 1, Section 

4.1.2.3.4). 

Calculation of Drinking Water Threat – Targets Factor Category Value: 1 + 2 + 5 =8 

4.1.3.2 Human Food Chain Threat -- Waste Characteristics 

4.1.3.2.1 Toxicity/Persistence/Bioaccumulation 

Table 10 below summarizes the Human Food Chain Threat - Waste Characteristics Factor Values for PCBs 

present in the source at the SCSD Site (see Sections 2.2.2 and 4.1.2.1.1 of this HRS documentation record). 

TABLE 10 

HUMAN FOOD CHAIN THREAT - WASTE CHARACTERISTICS FACTOR VALUES 

Hazardous 

Substance 

Source 

No. 

Toxicity 

Factor 

Value 

Persistence 

Factor 

Value* 

Bioaccumulation 

Factor Value* 

Toxicity/ 

Persistence/ 

Bioaccumulation 

Value (Table 4-

15) 

Reference 

PCBs 1 10,000 1.0 50,000 500,000,000 Ref. 2, p. 

B1-10 

Note: 

*Persistence factor value and bioaccumulation factor value for fresh water, because Lake St. Clair is a fresh
 

water body, and therefore, the targets are in fresh water. 

The hazardous substance having the highest toxicity/persistence/bioaccumulation value of 5 x 108

 is for PCBs. 

Toxicity/Persistence/Bioaccumulation Factor Value: 5 x 108

 (500,000,000) 

4.1.3.2.2 Hazardous Waste Quantity 

Table 11 below summarizes the Hazardous Waste Quantity Value and the Containment Value for Surface 

Water for the source at the SCSD site (see Sections 2.2.2 and 4.1.2.1.1 of this HRS documentation record). 

37 
38 

TABLE 11 

HAZARDOUS WASTE QUANTITY VALUE AND 

CONTAINMENT VALUE FOR SURFACE WATER

Source Source Hazardous Waste 

Quantity Value* 

Containment Value for 

Surface Water** 

1. Other – Sewer pipes and 

contaminated soil surrounding 

sewer pipes 

>0 10 

Notes: 

* - See Section 2.4.2.2 of this HRS documentation record 

** - Ref. 1, p. 51610, Table 4-2 

The source Hazardous Waste Quantity Value is unknown but greater than zero. According to Section 2.4.2.2 

of the HRS, a minimum pathway hazardous waste quantity factor value of 100 was assigned based on that the 

hazardous constituent quantity is not adequately determined, and based on the Level II concentrations in the 

surface migration pathway (Section 2.4.2.2). 

Hazardous Waste Quantity Factor Value: 100 

(Ref. 1, p. 51591, Table 2-6) 

4.1.3.2.3 Waste Characteristics Factor Category Value 

4.1.2.2.3 Waste Characteristics Factor Category Value 

The waste characteristics factor category value was assigned based on the waste characteristics product. The 

waste characteristics product is the product of the toxicity/persistence factor value and the hazardous waste 

quantity factor value (Ref. 1, Section 4.1.2.2.3). Values from the substance with the highest 

toxicity/persistence factor value for the watershed (PCBs) were used (Ref. 1, Section 4.1.2.2.3). 

A hazardous waste quantity factor value of 100 was assigned as described above. 

Toxicity/Persistence Factor Value: 10,000 

Hazardous Waste Quantity Factor Value: 100 

(Toxicity/Persistence x Hazardous Waste Quantity): 

10,000 x 100 = 1.0 x 106 

Bioaccumulation Potential Factor Value: 50,000

(Toxicity/persistence x hazardous waste quantity) x food chain bioaccumulation factor value: 5 x 1010 

(Ref. 1, p. 51592) 

(1 x 106

) x(5 x 104) = 5 x 1010

Waste Characteristics Factor Category Value: 320 

(Ref. 1, p. 51592, Table 2-7) 
39 

4.1.3.3 Human Food Chain Targets 

Level I concentrations for the Human Food Chain Threat were not evaluated. 

The zone of actual contamination associated with the surface water pathway is bounded by sediment samples 

SD2 and SD3 collected from Lange Street Canal; SD5, SD6 and SD7 collected from Revere Street Canal, and 

SD26 collected from Lake St. Clair. All of these sediment samples meet observed release criteria (Refer to 

Section 4.1.2.1.1 of this documentation record). Lake St. Clair is considered a fishery; fish are caught for 

human consumption within the zone of actual contamination, based on interviews with persons who fish within 

this zone (Refs. 18, p. 1;19, pp. 9, 10; 34). Lake St. Clair also is used for boating, and swimming (Ref. 18, p. 

1). The most likely source of human exposure to PCBs is through the eating of contaminated fish (Ref. 20, p. 

11). The Michigan Department of Community Health (MDCH) has issued a Do Not Eat advisory for several 

fish species caught in Lake St. Clair because of PCB contamination (Refs. 20, pp. 11, 12; 21, p. 8; 22, p. 8). 

4.1.3.3.1 Food Chain Individual 

There are Level II releases of contaminants having a bioaccumulation factor of 500 or greater to Lake St. Clair, 

which is considered a fishery (see Section 4.1.3.3 of this HRS documentation record). The observed release 

has been established by the presence of hazardous substances in an observed release through chemical analysis 

(Ref. 1, p. 51620); therefore, a food chain individual factor value of 45 was assigned. 

Food Chain Individual Factor Value: 45 

4.1.3.3.2 Population 

4.1.3.3.2.1 Level I Concentrations 

Level I concentrations were not evaluated. 

Level I Concentrations: NS 

4.1.3.3.2.2 Level II Concentrations 

An observed release of PCBs has been documented (see Section 4.1.2.1.1 of this HRS documentation record). 

Lake St. Clair is considered a fishery (Refs. 18, p. 1; 19, pp. 9, 10). The zone of actual contamination is 

bounded by sediment samples SD2 and SD3 collected from Lange Street Canal; SD5, SD6 and SD7 collected 

from Revere Street Canal and SD26 collected from Lake St. Clair. All these sediment samples meet observed 

release criteria (refer to Section 4.1.2.1.1 of this documentation record). Lake St. Clair also is used for boating, 

and swimming (Ref. 18, p. 1). The most likely source of human exposure to PCBs is through the eating of 

contaminated fish (Ref. 20, p. 11). The MDCH has issued a Do Not Eat advisory for several fish species 

caught in the Lake St. Clair because of PCB contamination (Refs. 20, pp. 11, 12; 21, p. 8; 22, p. 8; 23, p. 39). 

The fish caught in Lake St. Clair within the zone of contamination described above are utilized for human 
40 

consumption (Ref. 34, p. 1). While the exact amount is unknown, the amount of fish caught for consumption 

by humans within the zone of actual contamination is estimated to be greater than 0 pounds (Ref. 34, p. 1). As 

instructed in Section 4.1.3.3.2.2 and Table 4-18 of the HRS (Ref. 1 p. 51621), the human food chain 

population was assigned a value of 0.03. 

Level II Concentrations: 0.03 

4.1.3.3.2.3 Potential Contamination 

Fisheries (the Detroit River) are present downstream of releases associated with the site (Ref. 19, p. 9); 

however, downstream fisheries were not included because they would not significantly impact the site score. 

4.1.4 Environmental Threat 

Sensitive environments (wetlands) are located within the TDL (Refs. 22, 23); however, these targets were not 

included because they would not significantly impact the site score.