HRS DOCUMENTATION RECORD--REVIEW COVER SHEET 

Name of Site: Cabo Rojo Ground Water Contamination 

CERCLIS ID No.: PRN000206319 

Date Prepared: October 2010 

Contact Persons 

Site Investigations: Denise V. Zeno 

U.S. Environmental Protectio

New York, NY 

(212) 637-4319 

n Agency 

Documentation Record: Ildefonso Acosta 

U.S. Environmental Protectio

New York, NY 

(212) 637-4344 

n Agency 

Michele L. Capriglione 

Weston Solutions, Inc. (Regio

Edison, NJ 

(732) 417-5808 

n 2 SAT 2 contractor) 

Pathways, Components, or Threats Not Scored 

The surface water, soil exposure, and air pathways were not scored because the listing decision is not significantly 

affected by those pathways. The site score is sufficient to list the site on the ground water pathway score. 
This page has been left blank intentionally. 
 

 

 

HRS DOCUMENTATION RECORD 

Name of Site: Cabo Rojo Ground Water Contamination 

CERCLIS ID No.: PRN000206319 

EPA Region: 2 Date Prepared: October 2010 

Street Address of Site: * Cross streets Calle Barbosa and Calle De Diego, Cabo Rojo, Puerto Rico 00623 

County and State: Cabo Rojo Municipality, Puerto Rico 

General Location in the State: southwestern Puerto Rico 

Topographic Map: Puerto Real, PR 

Ana Maria well: 

Latitude: 18° 05' 26.61" North (18.09073°) Longitude: 67° 08' 53.97" West (-67.14832°) 

Club de Leones well: 

Latitude: 18° 05' 38.38" North (18.09399°) Longitude: 67° 07' 59.79" West (-67.13328°) 

[Ref. 3, p. 1; 4, p. 1; 12, p. 1] 

The site consists of a ground water plume with no identified source(s) of contamination. Therefore, the reference points 

for the site’s latitude and longitude coordinates are the two wells with an observed release of contamination (i.e., the Ana 

Maria well and the Club de Leones well) [Figure 1; Ref. 1, p. 51595]. 

* The street address presented in this HRS documentation record identifies the nearest intersection to the Ana Maria well. 

The Ana Maria well is located approximately 660 feet (0.12 mile) northwest of the intersection of Calle Barbosa and 

Calle De Diego [Ref. 12, pp. 1-3]. 

* The street address, coordinates, and contaminant locations presented in this HRS documentation record identify the 

general area 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 precisely 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 CERCLA. Accordingly, 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. 

 Scores 

Ground Water Pathway 100.00 

Surface Water Pathway Not Scored 

Soil Exposure Pathway Not Scored 

Air Pathway Not Scored 

HRS SITE SCORE 50.00 

1 
, "' . ",,'I ~ 

J ,: ~' 

.. .,.' . 

,~. 

< , 

'. L.._~ ___ ..,.._..,._...J' 'l$.' 

SOURCES: 

1. USGS. 7.5 Minute Series Topographic Quadrangle.: Puerto Real, PR; San Garman, PR. 

2. Weston Solutions, Inc. (WESTON). Cabo Rojo Site Disoovery Initiative SHe Logbook, DCN No. SAT2.20113.030.001 . June 30, 2006· December 7, 2006. 

Site Location Map 

Cabo RoJo Ground Water Contamination 

Cabo RoJo. Puerto Rico 

Cabo Rojo Ground Water Contamination 

LEGEND: 

• (} 

• [ Q.IB<TNAM'" 

Well Location 

Possible Source 

Area of Observed Ground Water Contamination 

Center of Area of Observed Ground Water Contamination 

EPA I ~T'" June 2010 

FIGURE .. 

I .:. " _ " 

L ' " '.'.1 

; .-
W*' S 

'''-. 

,, ~ "", .., , ...... 

\, ·t

l 

• ••. ~ "" "; 

. ... " . JYi.UI!~: .... : '~ "- ' 

- -",.. I '2. ' 

~:: ; ; :: ' ~ ~ 

...

'. 

! ­

1,' - ~ Ii· ,'. 

./ 

) " ~) 

:'( ..: . ' <~.,. { .• ":- ~ ""; • 'C. .lr..~ ' . --..1 h "~ -­ •

(\ . ~ r\ U pII 

"- 2 '~" t ''' ,;,·','' ·· ··· .. 

.':f;t~~~y; ~·y ~ \. .: '-' / I 

\ 

1. USGS. 7.5 Minute Series Topographic Quadrangles: Puerto Real. PR: San German. PRo 

2. Westan Solutions. Inc. (WESTON). Cabo Rojo Site Discovery InitiaUve Site Logbook, DCN No. SAT2.20113.030.001 . June 30. 2006- December 7.2006. 

TilLE: 

Study Area Map 

Cabo Raja Ground Water Contamination 

Cabo Raja, Puerto Rico 
 

 

 

WORKSHEET FOR COMPUTING HRS SITE SCORE 

Cabo Rojo Ground Water Contamination 

1. 

2a. 

2b. 

2c. 

3. 

4. 

5. 

6. 

Ground Water Migration Pathway Score (Sgw) 

(from Table 3-1, line 13) 

Surface Water Overland/Flood Migration Component 

(from Table 4-1, line 30) 

Ground Water to Surface Water Migration Component 

(from Table 4-25, line 28) 

Surface Water Migration Pathway Score (Ssw) 

Enter the larger of lines 2a and 2b as the pathway score. 

Soil Exposure Pathway Score (Ss) 

(from Table 5-1, line 22) 

Air Migration Pathway Score (Sa) 

(from Table 6-1, line 12) 

Total of Sgw 2

 + Ssw 2 + Ss 

2

 + Sa 

2

HRS Site Score Divide the value on line 5 

by 4 and take the square root 

S

100.00

Not Scored 

Not Scored 

Not Scored 

Not Scored 

Not Scored 

10,000 

50.00 

S2 

10,000 

4 
 

 

 

 

 

 

GROUND WATER MIGRATION PATHWAY SCORESHEET 

Cabo Rojo Ground Water Contamination
 

GROUND WATER MIGRATION PATHWAY MAXIMUM VALUE VALUE ASSIGNED 

Factor Categories & Factors 

Likelihood of Release to an Aquifer 

Aquifer: Bedrock Aquifer 

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 500 

[lines 2a (2b+2c+2d)] 

3. Likelihood of Release 550 550 

Waste Characteristics 

4. Toxicity/Mobility * 10,000 

5. Hazardous Waste Quantity * 100 

6. Waste Characteristics 100 32 

Targets 

7. Nearest Well 50 50 

8. Population 

8a. Level I Concentrations ** 18,560 

8b. Level II Concentrations ** 7,509 

8c. Potential Contamination ** NS 

8d. Population (lines 8a+8b+8c) ** 26,069 

9. Resources 5 5 

10. Wellhead Protection Area 20 20 

11. Targets (lines 7+8d+9+10) ** 26,144 

12. Targets (including overlaying aquifers) ** 26,144 

13. Aquifer Score (lines 3x6x12 divided by 82,500) 100 100 

GROUND WATER MIGRATION PATHWAY SCORE 100 100.00 

(Sgw) 

* Maximum value applies to waste characteristics category. 

** Maximum value not applicable. 

5 
 

REFERENCES 

Reference 

Number Description of the Reference 

1.	 U.S. Environmental Protection Agency (EPA). Hazard Ranking System, Final Rule, Federal Register, 

Volume 55, No. 241. December 14, 1990. [137 pages] 

2.	 EPA. Superfund Chemical Data Matrix (excerpts), Methodology and Introduction, Appendix B-I 

(Hazardous Substances Factor Values), Appendix B-II (Hazardous Substances Benchmarks, and Appendix 

C (Synonyms) January 27, 2004 and Appendix A (Trichloroethylene (TCE) updates). October 23, 2006. 

From http:// www.epa.gov/superfund/sites/npl/hrsres/tools/scdm.htm. Web Page last updated on May 26, 

2010; Accessed and printed on June 3, 2010. [62 pages] 

3.	 Capriglione, Michele, Weston Solutions, Inc. (Weston). Project Note to Cabo Rojo Groundwater 

Contamination HRS File, Subject: Latitude and Longitude Determination. March 16, 2010. [1 page] 

4.	 U.S. Department of the Interior Geological Survey (USGS). Puerto Real Quadrangle, Puerto Rico, 7.5-

Minute Series (Topographic). 1966. [1 page] 

5.	 Capriglione, Michele, Weston. Project Note to Cabo Rojo Groundwater Contamination HRS File, Subject: 

Compilation of analytical data sheets from 2002-2006 of Volatile Organic Compounds (VOCs) analyses 

obtained from Puerto Rico Aqueduct and Sewer Authority (PRASA). June 3, 2010. [18 pages] 

6.	 Capriglione, Michele, Weston. Project Note to Cabo Rojo Groundwater Contamination HRS File, Subject: 

Populations associated with the Ana Maria and Club de Leones Well (with Attached References). June 1, 

2010. [7 pages] 

7.	 Capriglione, Michele, Weston. Sampling Trip Report, Work Assignment No.: 030, Cabo Rojo Site 

Discovery Initiative. July 19, 2006. [23 pages] 

8.	 EPA Hazardous Waste Support Section/Regional Sample Control Center. Record of Communication to 

HWSS/ESAT-TOPO and attached CLP Data Assessment, Subject: CLP [Organic] Data Package for 

Quality Assurance Review, Site: Cabo Rojo SDI, Case #: 35509. August 10–August 29, 2006. [257 

pages] 

9.	 Weston. Site Logbook. Cabo Rojo Site Discovery Initiative Logbooks. WO: 20113.111.002.0030.00, 

DCN: SAT2.20113.030.001 and SAT2.20113.030.002. June 30, 2006 through December 7, 2006. [61 

pages] 

10.	 Puerto Rico Environmental Quality Board (PREQB). Final Wellhead Protection Program. April 1991. 

[103 pages] 

11.	 EPA. Region 2 Water, Wellhead Protection Program. From http://www.epa.gov/region02/water/whp.htm. 

Web Page last updated on August 28, 2009; Accessed and printed on February 23, 2010. [1 page] 

12.	 Capriglione, Michele, Weston. Project Note to Cabo Rojo Groundwater Contamination HRS File, Subject: 

Location of the Ana Maria Well in relation to the street address of the site (with Attached References). 

August 10, 2010. [3 pages] 

13.	 Capriglione, Michele, Weston. Project Note to Cabo Rojo Groundwater Contamination HRS File, Subject: 

Compilation of Well Construction Details (with Attached References). July 23, 2010. [13 pages] 

14.	 Weston. Site Logbook. Cabo Rojo Groundwater Contamination HRS Logbook. WO: 

20113.111.002.0125.00, DCN: SAT2.20113.125.001. September 2, 2009. [6 pages] 

6 
 

 

REFERENCES (continued) 

Reference 

Number Description of the Reference 

15.	 Capriglione, Michele, Weston. Sampling Trip Report. Work Assignment No.: 0125, Cabo Rojo 

Groundwater Contamination HRS/NPL. September 10, 2009. [9 pages] 

16.	 EPA Hazardous Waste Support Section/Regional Sample Control Center. Record of Communication to 

HWSS/ESAT-TOPO and attached CLP Data Assessment, Subject: CLP [Organic] Data Package for 

Quality Assurance Review, Site: Cabo Rojo Groundwater Contamination, Case #: 38927. September 23-

October 5, 2009. [25 pages] 

17.	 Snyder, Scott, Weston. Project Note to D’Elegant Fantastic Dry Cleaners File (with attached field 

documentation), Subject: Compilation of Site Field Notes. August 29, 2007. [44 pages] 

18.	 Gaughan, Daniel J., Weston. Sampling Trip Report. Work Assignment No.: 066, D’Elegant Fantastic Dry 

Cleaners. July 5, 2007. [12 pages] 

19.	 EPA Hazardous Waste Support Section/Regional Sample Control Center. Record of Communication to 

HWSS/ESAT-TOPO and attached CLP Data Assessment, Subject: CLP [Organic] Data Package for 

Quality Assurance Review, Site: D’Elegant Fantastic Dry Cleaners, Case #: 36469. July 6-12, 2007. [74 

pages] 

20.	 Snyder, Scott, Weston. Project Note to Extasy Q Prints File (with attached field documentation), Subject: 

Compilation of Site Field Notes. August 30, 2007. [55 pages] 

21.	 Gaughan, Daniel J., Weston. Sampling Trip Report. Work Assignment No.: 070, Extasy Q Prints. July 5, 

2007. [16 pages] 

22.	 EPA Hazardous Waste Support Section/Regional Sample Control Center. Record of Communication to 

HWSS/ESAT-TOPO and attached CLP Data Assessment, Subject: CLP [Organic] Data Package for 

Quality Assurance Review, Site: Extasy Q Prints, Case #: 36476. July 18-August 14, 2007. [94 pages] 

23.	 Snyder, Scott, Weston. Project Note to Cabo Rojo Professional Dry Cleaners File (with attached field 

documentation), Subject: Compilation of Site Field Notes. August 29, 2007. [45 pages] 

24.	 Gaughan, Daniel J., Weston. Sampling Trip Report. Work Assignment No.: 067, Cabo Rojo Professional 

Dry Cleaners. July 10, 2007. [15 pages] 

25.	 EPA Hazardous Waste Support Section/Regional Sample Control Center. Record of Communication to 

HWSS/ESAT-TOPO and attached CLP Data Assessment, Subject: CLP [Organic] Data Package for 

Quality Assurance Review, Site: Cabo Rojo Professional Dry Cleaners, Case #: 36477. July 17-26, 2007. 

[86 pages] 

26.	 Capriglione, Michele, Weston. Pre-CERCLIS Screening Report, Cabo Rojo Site Discovery Initiative, 

Cabo Rojo, Puerto Rico, Document Control No. SAT2.20113.030.330 (without appendices). Prepared for 

United States Environmental Protection Agency. February 2007. [35 pages] 

27.	 Interstate Technology and Regulatory Cooperation Work Group In Situ Bioremediation Work Team. 

Natural Attenuation of Chlorinated Solvents in Groundwater: Principles and Practices. September 1999. [8 

pages] 

7 
REFERENCES (continued) 

Reference 

Number Description of the Reference 

28.	 Renken, Robert A., USGS, et al. Geology and Hydrogeology of the Caribbean Islands Aquifer System of 

the Commonwealth of Puerto Rico and the U.S. Virgin Islands; excerpts. USGS Professional Paper 1419. 

2002. [23 pages] 

29.	 Rodríguez, José M., USGS. Assessment of Ground-Water Withdrawals at Municipal Industrial Parks in 

Puerto Rico, 2000; excerpts. Scientific Investigation Report 2004-5029. Prepared in cooperation with 

Puerto Rico Industrial Development Company (PRIDCO). 2004. [22 pages] 

30.	 Rodríguez-Martínez, Jesus, USGS. Hydrology and Ground-Water/Surface-Water Relations in the Bajura 

Area of the Municipio of Cabo Rojo, Southwestern Puerto Rico. Water-Resources Investigations Report 

95-4159. Prepared in cooperation with Puerto Rico Aqueduct and Sewer Authority (PRASA). 1996. [36 

pages] 

31.	 Veve, Thalia D., USGS. Atlas of Ground-Water Resources in Puerto Rico and the U.S. Virgin Islands, 

Section 2.3.2: Guanajibo Region; excerpts. Water Resources Investigations Report 94-4198. Prepared in 

cooperation with EPA. 1996. [24 pages] 

32.	 USEPA, Contract Laboratory Program. National Functional Guidelines for Superfund Organic Methods 

Data Review; excerpt. June 2008. [6 pages] 

33.	 USEPA, Contract Laboratory Program. Statement of Work for Organic Analysis Multi-Media, MultiConcentration SOM01.1; Exhibit B. May 2005. [9 pages] 

34.	 EPA, Envirofacts Warehouse. MultiSystem Report, Cabo Rojo Professional Dry Cleaners. From 

http://oaspub.epa.gov/enviro/multisys2.get_list?facility_uin=110028288500. Web page last updated, 

accessed, and printed on April 8, 2010. [1 page] 

35.	 EPA, Envirofacts Warehouse. MultiSystem Report, D’Elegant Fantastic Dry Cleaners. From 

http://oaspub.epa.gov/enviro/multisys2.get_list?facility_uin=1100282885234. Web page last updated, 

accessed, and printed on April 8, 2010. [1 page] 

36.	 EPA, Envirofacts Warehouse. MultiSystem, Report Modern Man Dry Cleaners. From 

http://oaspub.epa.gov/enviro/multisys2.get_list?facility_uin=110014361519. Web page last updated, 

accessed, and printed on April 8, 2010. [2 pages] 

37.	 Capriglione, Michele, Weston. Project Note to Cabo Rojo Groundwater Contamination HRS File, Subject: 

Summary of the Cabo Rojo Source Investigation. July 29, 2010. [1 page] 

38.	 Gaughan, Daniel J., Weston. Sampling Trip Report. Work Assignment No.: 079, Borincano Dry Cleaning. 

July 6, 2007. [10 pages] 

39.	 EPA Hazardous Waste Support Section/Regional Sample Control Center. Record of Communication to 

HWSS/ESAT-TOPO and attached CLP Data Assessment, Subject: CLP [Organic] Data Package for 

Quality Assurance Review, Site: Borincano Dry Cleaning, Case #: 36479. July 12-25, 2007. [58 pages] 

40.	 Gaughan, Daniel J., Weston. Sampling Trip Report. Work Assignment No.: 072, Centro de Acopio (Obras 

Publicas). July 5, 2007. [23 pages] 

8 
 

REFERENCES (continued) 

Reference 

Number Description of the Reference 

41.	 EPA Hazardous Waste Support Section/Regional Sample Control Center. Record of Communication to 

HWSS/ESAT-TOPO and attached CLP Data Assessment, Subject: CLP [Organic] Data Package for 

Quality Assurance Review, Site: Centro de Acopio (Obras Publicas), Case #: 36478. July 10-24, 2007. 

[401 pages] 

42.	 Gaughan, Daniel J., Weston. Sampling Trip Report. Work Assignment No.: 073, Centro de Transmiciones. 

July 10, 2007. [16 pages] 

43.	 EPA Hazardous Waste Support Section/Regional Sample Control Center. Record of Communication to 

HWSS/ESAT-TOPO and attached CLP Data Assessment, Subject: CLP [Organic] Data Package for 

Quality Assurance Review, Site: Centro de Transmiciones, Case #: 36468. July 10-20, 2007. [60 pages] 

44.	 EPA Hazardous Waste Support Section/Regional Sample Control Center. Record of Communication to 

HWSS/ESAT-TOPO and attached CLP Data Assessment, Subject: CLP [Organic] Data Package for 

Quality Assurance Review, Site: Centro de Transmiciones, Case #: 36468. July 10-26, 2007. [143 pages] 

45.	 Gaughan, Daniel J., Weston. Sampling Trip Report. Work Assignment No.: 069, Former Eaton CutlerHammer Electrical Co. July 9, 2007. [25 pages] 

46.	 EPA Hazardous Waste Support Section/Regional Sample Control Center. Record of Communication to 

HWSS/ESAT-TOPO and attached CLP Data Assessment, Subject: CLP [Organic] Data Package for 

Quality Assurance Review, Site: Former Eaton Cutler-Hammer Elec. Co., Case #: 36470. July 18, 2007-

August 10, 2007. [399 pages] 

47.	 Gaughan, Daniel J., Weston. Sampling Trip Report. Work Assignment No.: 078, Future Blinds Automobile 

Commercial Area. July 10, 2007. [18 pages] 

48.	 EPA Hazardous Waste Support Section/Regional Sample Control Center. Record of Communication to 

HWSS/ESAT-TOPO and attached CLP Data Assessment, Subject: CLP [Organic] Data Package for 

Quality Assurance Review, Site: Future Blinds Automobile Commercial, Case #: 36475. July 17, 2007-

August 6, 2007. [292 pages] 

49.	 Gaughan, Daniel J., Weston. Sampling Trip Report. Work Assignment No.: 075, Junny Auto Paint. July 

11, 2007. [22 pages] 

50.	 EPA Hazardous Waste Support Section/Regional Sample Control Center. Record of Communication to 

HWSS/ESAT-TOPO and attached CLP Data Assessment, Subject: CLP [Organic] Data Package for 

Quality Assurance Review, Site: Junny Auto Paint, Case #: 36474. July 20, 2007-August 15, 2007. [199 

pages] 

51.	 EPA Hazardous Waste Support Section/Regional Sample Control Center. Record of Communication to 

HWSS/ESAT-TOPO and attached CLP Data Assessment, Subject: CLP [Organic] Data Package for 

Quality Assurance Review, Site: Junny Auto Paint, Case #: 36474. July 13-31, 2007. [161 pages] 

52.	 Gaughan, Daniel J., Weston. Sampling Trip Report. Work Assignment No.: 074, Junker Kenny Inc. July 

11, 2007. [14 pages] 

9 
REFERENCES (continued) 

Reference 

Number Description of the Reference 

53.	 EPA Hazardous Waste Support Section/Regional Sample Control Center. Record of Communication to 

HWSS/ESAT-TOPO and attached CLP Data Assessment, Subject: CLP [Organic] Data Package for 

Quality Assurance Review, Site: Junker Kenny Inc., Case #: 36471. July 20, 2007-August 15, 2007. [178 

pages] 

54.	 Gaughan, Daniel J., Weston. Sampling Trip Report. Work Assignment No.: 076, L & R Auto and Truck 

Repair, July 11, 2007. [13 pages] 

55.	 EPA Hazardous Waste Support Section/Regional Sample Control Center. Record of Communication to 

HWSS/ESAT-TOPO and attached CLP Data Assessment, Subject: CLP [Organic] Data Package for 

Quality Assurance Review, Site: L&R Auto and Truck Repair, Case #: 36472. July 17, 2007-August 7, 

2007. [183 pages] 

56.	 Gaughan, Daniel J., Weston. Sampling Trip Report. Work Assignment No.: 077, Radiadores W/Papo 

Quinones Auto Repair Shop. July 11, 2007. [23 pages] 

57.	 EPA Hazardous Waste Support Section/Regional Sample Control Center. Record of Communication to 

HWSS/ESAT-TOPO and attached CLP Data Assessment, Subject: CLP [Organic] Data Package for 

Quality Assurance Review, Site: Radiadores W/Papo Quinones Auto, Case #: 36473. July 18, 2007-August 

14, 2007. [266 pages] 

58.	 AllBusiness, A D&B Company. Cattle Ranching & Farming – Cabo Rojo Puerto Rico. From 

http://www.allbusiness.com/companyindex/Puerto_Rico/Cabo_Rojo/Cattle_Ranching_and_Farming/B54E 

570C4D7F07B4EBB7908EE5D8892A-1.html. Accessed and printed on June 10, 2010. [2 pages] 

59.	 Capriglione, Michele, Weston and Roberto Ayala of Puerto Rico Environmental Quality Board. 

Documentation of Communication, Subject: Wellhead Protection Area for Public Supply Wells in Cabo 

Rojo, Puerto Rico. June 16, 2010. [1 page] 

60.	 Weston. Figure 3: 4-Mile Radius Map, Cabo Rojo Ground Water Contamination. May 27, 2010. [1 page] 

61.	 Capriglione, Michele, Weston. Project Note to Cabo Rojo Groundwater Contamination HRS File, Subject: 

Determination of Hydraulic Conductivity for the Ana Maria and Club de Leones wells (with Attached 

References). July 27, 2010. [14 pages] 

10 
 

 

 

 

SITE SUMMARY 

The Cabo Rojo Ground Water Contamination site (CERCLIS ID No. PRN000206319) consists of a ground water plume 

with no identified source(s) of contamination [Ref. 12, p. 2]. It is located in the municipality of Cabo Rojo in 

southwestern Puerto Rico [Figure 1; Ref. 4, p. 1; 12, p. 2]. The reference points for the site are the two wells with an 

observed release of contamination, Ana Maria and Club de Leones [Figure 1; Ref. 1, p. 51595; 3, p. 1]. The geographic 

coordinates of the Ana Maria well are 18.09073o latitude and -67.14832 o longitude and the coordinates of the Club de 

Leones well are 18.09399o latitude and -67.13328 o longitude [Figure 1; Ref. 3, p. 1]. 

The Cabo Rojo Urbano public water system consists of six wells (Hacienda la Margarita, Cabo Rojo 1, Cabo Rojo 2, 

Cabo Rojo 3, Club de Leones, and Ana Maria) and one surface water source which serve an estimated population of 

46,911people [Ref. 6, pp. 1, 6]. The Ana Maria well acts as an independent system which serves approximately 1,856 

persons; the other components are blended to serve approximately 45,055 persons [Ref. 6, p. 1]. Quarterly ground water 

samples collected by the system’s operator, Puerto Rico Aqueduct and Sewer Authority (PRASA), indicate that the 

chlorinated solvents tetrachloroethylene (PCE) and trichloroethylene (TCE) were detected in samples collected from the 

Hacienda la Margarita well in 2004 and 2005 and on numerous occasions in samples collected from the Ana Maria well 

from 2002 to 2006 [Ref. 5, pp. 1-18]. PCE was detected in ground water samples collected from the Ana Maria well at 

concentrations ranging from 1.8 micrograms per liter (μg/L) to 4.0 μg/L and TCE was detected at concentrations ranging 

from 0.5 μg/L to 1.6 μg/L [Ref. 5, pp. 1-10, 12, 14, 16-18]. 

The U.S. Environmental Protection Agency (EPA) collected 13 ground water samples from active public and private 

supply wells in and around Cabo Rojo (including the six public supply wells which comprise the Cabo Rojo Urbano 

system) in July 2006 [Ref. 6, p. 1; 7, pp. 2-5, 7, 9-15, 18-21; 9, pp. 7-17]. In all instances ground water samples were 

collected prior to treatment (i.e., chlorination) [Ref. 9, p. 8]. In most cases samples were collected from the spigot 

designated for raw water sampling; however, where the spigot was not present (i.e., CR-GW03 collected from Cabo Rojo 

3), the sample was collected directly from a pipe on the well, prior to chlorination [Ref. 7, p. 5; 9, pp. 8, 10]. Chlorinated 

solvents were detected in ground water samples collected from the Ana Maria and the Club de Leones wells but were not 

detected in the other wells tested including the Hacienda la Margarita well [Ref. 7, p. 5; 8, pp. 1-34, 51, 52, 57, 69-70, 

251, 252; 9, p. 10]. Ground water sample CR-GW04, collected from the Ana Maria well, indicated the presence of PCE 

(1.9 μg/L), TCE (0.63 μg/L), and cis-1,2-dichloroethylene (cis-1,2-DCE) (0.67 μg/L) [Ref. 7, p. 5; 8, pp. 51, 52; 9, p. 10]. 

 Duplicate sample CR-GW14, also collected from the Ana Maria well, revealed similar detections of PCE (1.9 μg/L), 

TCE (0.62 μg/L), and cis-1,2-DCE (0.66 μg/L) [Ref. 7, p. 5; 8, pp. 69-70, 251; 9, p. 10]. Ground water sample CRGW06, which was collected from the Club de Leones well, indicated the presence of 1,1-dichloroethylene (1,1-DCE) at 

0.96 μg/L [Ref. 7, p. 5; 8, p. 57; 9, p. 10]. Chlorinated solvents were not detected in any other ground water samples 

collected in July 2006, including ground water samples CR-GW02 and CR-GW03, collected from public supply wells 

Cabo Rojo 2 and Cabo Rojo 3, respectively [Ref. 7, pp. 5, 7; 8, pp. 1-34, 42-80; 9, pp. 7-17; 32, p. 6]. Ground water 

samples CR-GW02 and CR-GW03 indicated non-detect values for PCE, TCE, cis-1,2-DCE, and 1,1-DCE and were 

chosen to demonstrate background ground water conditions [Ref. 7, pp. 5, 7; 8, pp. 45-46, 48-49, 250; 9, p. 10; 32, p. 6]. 

From November 29 through December 7, 2006, EPA conducted site reconnaissance activities at 68 facilities within the 

municipality of Cabo Rojo [Ref. 9, pp. 18-40, 43-61; 26, pp. 8-33]. Based on the results of the reconnaissance activities, 

EPA identified 15 facilities for further investigation [Ref. 26, p. 34; 37, p. 1]. In January 2007, EPA conducted source 

investigations at fifteen facilities in Cabo Rojo which were identified as potential sources of the ground water 

contamination [Ref. 37, p.1]. Although chlorinated solvents (i.e., PCE, TCE, cis-1,2-DCE, trans-1,2-dichloroethylene 

[trans-1,2-DCE], and vinyl chloride) were detected at three of these facilities, EPA did not identify the source of ground 

water contamination in the public supply wells as contamination was not detected in both a source and ground water 

release at two of the facilities, and a connection between a release at the third facility and the ground water plume 

impacting the public wells could not be established [Ref. 19, pp. 13-14, 34-35, 37-38; 22, pp. 39, 42, 45; 25, pp. 9, 18, 

21]. 

In September 2009, EPA collected additional ground water samples from the wells Ana Maria and Club de Leones and 

from two background wells (i.e., Cabo Rojo 2 and Cabo Rojo 3) [Ref. 14, pp. 4-5]. PCE was detected at 1.1 μg/L in 

aqueous sample CRGC-GW01 and its duplicate CRGC-GW02 collected from the Ana Maria well [Ref. 14, p. 5; 15, p. 4; 

16, pp. 1, 3, 6, 20-25]. Ground water sample CRGC-GW03 collected from the Club de Leones well indicated the 

11 
presence ofl,I-DCE at an estimated concentration [Ref. 14, p. 5; IS, p. 4; 16, pp. 11,21,25; 32, p. 6]. Analytical results 

for ground water samples CRGC-GW04 and CRGC-GW05, collected from designated background public supply wells 

Cabo Rojo 2 and Cabo Rojo 3, respectively, indicated non-detect values for PCE and I, I-DCE [Ref. 14, pp. 4, 5; IS, p. 4; 

16, pp. I, 14-1520-25,17-18; 32, p. 6]. 

12 
 

 

 

2.2 

SD-Characterization and Containment 

Source No.: 1 

SOURCE DESCRIPTION 

SOURCE CHARACTERIZATION 

Number of the source: 1 

Source Type of the source: Other 

Name and description of the source: Ground Water Plume – Cabo Rojo, Puerto Rico 

Source 1 is a contaminated ground water plume of unknown volume without an identified source. As shown in Section 

2.4.1, sampling results indicate the continuing presence of chlorinated solvents in two public supply wells. 

A ground water sample (CR-GW04) collected by EPA in July 2006 indicated the presence of PCE (1.9 μg/L) and TCE 

(0.63 μg/L) in the Ana Maria well; cis-1,2-DCE was also detected in this well at a concentration of 0.67 μg/L [Ref. 7, p. 

5, 11; 8, pp. 51-52; 9, p. 10]. A ground water sample collected from the Club de Leones well (CR-GW06), a component 

of the Cabo Rojo Urbano public water system, indicated the presence of 1,1-DCE at 0.96 μg/L [Ref. 6, pp. 1, 3; 7, pp. 5, 

12; 8, p. 57; 9, p. 10]. Analytical results of public supply wells Cabo Rojo 2 and Cabo Rojo 3, which were selected to 

establish background levels for the contaminated wells, indicated non-detect values for PCE, TCE, cis-1,2-DCE, and 1,1-

DCE [Ref. 7, pp. 5, 7; 8, pp. 45-46, 48-49; 9, p. 10; 32, p. 6]. 

In September 2009, EPA collected additional ground water samples from Ana Maria, Club de Leones, Cabo Rojo 2 and 

Cabo Rojo 3 [Ref. 14, p. 5]. PCE was detected at 1.1 μg/L in aqueous sample CRGC-GW01 and its duplicate CRGCGW02 collected from the Ana Maria well [Ref. 14, p. 5; 15, p. 4; 16, pp. 3, 6]. Ground water sample CRGC-GW03 

collected from the Club de Leones well indicated the presence of an estimated concentration of 1,1-DCE [Ref. 14, pp. 4, 

5; 15, p. 4; 16, p. 11; 32, p. 6]. Analytical results of ground water samples CRGC-GW04 and CRGC-GW05 collected 

from designated background public supply wells Cabo Rojo 2 and Cabo Rojo 3, respectively, indicated non-detect values 

for PCE and 1,1-DCE [Ref. 14, pp. 4-5; 15, p. 4; 16, pp. 14-15, 17-18; 32, p. 6]. 

EPA collected a total of 61 surface soil samples, 66 subsurface soil samples and 28 ground water samples from twelve 

facilities in an effort to identify potential sources of ground water contamination in Cabo Rojo [Ref.18, pp. 3-5; 21, pp. 3, 

5-6; 24, pp. 3-6; 38, pp. 3-4; 40, pp. 3-7; 42, pp. 3, 5; 45, pp. 3-7; 47, pp. 3-7; 49, pp. 3-7; 52, pp. 3, 5; 54, pp. 3-5; 56, 

pp. 3-7]. Samples collected from nine of these facilities did not indicate the presence of chlorinated solvents in soil or 

ground water samples; therefore these facilities are no longer considered possible sources of ground water contamination 

[Ref. 39, pp. 35-58; 41, pp. 37-93; 43, pp. 27-60; 44, pp. 117-122; 46, pp. 38-48, 202-246; 48, pp. 165-212; 50, pp. 30-

59; 51, pp. 41-52; 53, 146-166; 55, pp. 41-61; 57, pp. 119-163]. Chlorinated solvents (i.e., PCE, TCE, cis-1,2-DCE, 

trans-1,2-DCE, and vinyl chloride) were detected at the three remaining facilities; however, no facility in the immediate 

area of either the Ana Maria well or Club de Leones well had VOC contamination detected in both soil and ground water 

samples [Figure 2; Ref. 19, pp. 13-14, 34-35, 37-38; 22, pp. 39, 42, 45; 25, pp. 9, 18, 21]. The Attribution portion of the 

Observed Release (Section 3.1.1) of this documentation record provides more supporting detail. 

The Ana Maria well, which acts as an independent system, serves approximately 1,856 persons [Ref. 6, p. 1; 14, p. 3]. 

The Club de Leones well, associated with PRASA’s Cabo Rojo Urbano Water interconnected system, serves 

approximately 7,509 persons [Ref. 6, p. 1]. Quarterly ground water samples collected by PRASA, indicate that the 

chlorinated solvents PCE and TCE were detected in the Ana Maria well during the period 2002 to 2006 [Ref. 5, pp. 1-10, 

12, 14, 16-18]. The maximum concentrations of PCE and TCE detected in these wells during this period were 4.0 μg/L 

and 1.6 μg/L, respectively [Ref. 5, pp. 1, 3]. 

Location of the source, with Reference to a map of the site: 

The ground water plume is identified by contamination found in the Ana Maria and Club de Leones public supply wells. 

For the purpose of this documentation record, these wells represent a minimum of the plume extent. The hazardous 

substances associated with the Ana Maria well and the Club de Leones well are linked due to biodegradation (i.e., the 

anaerobic dechlorination of PCE proceeds via TCE to DCE) [Ref. 27, p. 8]. The well locations are shown in Figure 1. 

Cabo Rojo is located in the southwestern portion of Puerto Rico [Ref. 4, p. 1]. 

13 
SD-Characterization and Containment 

Source No.: 1 

Containment 

Release to ground water: 

Based on evidence of hazardous substance migration (i.e., contamination detected in ground water samples collected 

from two public supply wells) a containment factor of 10 is assigned [Ref. 1, p. 51596; 7, p. 5; 8, pp. 51-52, 57; 9, p. 10; 

14, p. 5; 15, p. 4; 16, pp. 2-3, 5-6, 11]. 

14 
 

 

 

SD- Hazardous Substances 

Source No.: 1 

2.4.1 Hazardous Substances 

Ground water samples collected by EPA in 2006 and 2009 show the presence of chlorinated solvents in two public 

supply wells, as described below. Background sample locations and contaminant levels for comparison to the 

contaminated samples collected during EPA’s 2006 and 2009 sampling events are discussed in Section 3.1.1 of this 

document. EPA collected surface soil samples, subsurface soil samples, and ground water samples from twelve facilities 

in an effort to identify potential sources of ground water contamination in Cabo Rojo [Ref.18, pp. 3-5; 21, pp. 3, 5-6; 24, 

pp. 3-6; 38, pp. 3-4; 40, pp. 3-7; 42, pp. 3, 5; 45, pp. 3-7; 47, pp. 3-7; 49, pp. 3-7; 52, pp. 3, 5; 54, pp. 3-5; 56, pp. 3-7]. 

Samples collected from nine of these facilities did not indicate the presence of chlorinated solvents in soil or ground 

water samples [Ref. 39, pp. 35-58; 41, pp. 37-93; 43, pp. 27-60; 44, pp. 117-122; 46, pp. 38-48, 202-246; 48, pp. 165-

212; 50, pp. 30-59; 51, pp. 41-52; 53, 146-166; 55, pp. 41-61; 57, pp. 119-163]. Chlorinated solvents (i.e., PCE, TCE, 

cis-1,2-DCE, trans-1,2-DCE, and vinyl chloride) were detected at the three remaining facilities; however, no facility in 

the immediate area of either the Ana Maria well or Club de Leones well had VOC contamination detected in both soil 

and ground water samples [Figure 2; Ref. 19, pp. 13-14, 34-35, 37-38; 22, pp. 39, 42, 45; 25, pp. 9, 18, 21]. 

EPA Sampling Event – Ground Water Samples: July 2006 

In July 2006, EPA collected ten ground water samples from nine PRASA-operated public supply wells, three ground 

water samples from three private wells, and pre- and post-treatment aqueous samples from the Boqueron Filtration Plant 

[Ref. 7, pp. 3-5, 9-15, 18-21; 8, pp. 248-257; 9, pp. 7-17]. Samples CR-GW04, and CR-GW14 were collected from the 

Ana Maria well, sample CR-GW06 was collected from the Club de Leones well; and background samples CR-GW02 and 

CR-GW03 were collected from the Cabo Rojo 2 and Cabo Rojo 3 wells, respectively [Ref. 7, p. 5; 9, pp. 7-17]. EPA 

validated the trace volatile organic compounds (VOCs) data according to Standard Operating Procedure (SOP) HW-34 

(Revision 0), “USEPA Region II Data Validation SOP for Statement of Work SOM01.1” [Ref. 8, pp. 1-31]. EPA found 

the VOC data to be valid and acceptable, including meeting the Contract Required Quantitation Limit (CRQL) 

requirements [Ref. 8, pp. 1-31]. 

Ground water sample CR-GW04, collected from the Ana Maria well indicated PCE (1.9 μg/L), TCE (0.63 μg/L), and cis1,2-DCE (0.67 μg/L) [Ref. 7, pp. 5, 7; 8, pp. 1-34, 51, 52, 251; 9, p. 10]. Duplicate sample CR-GW14, also collected 

from the Ana Maria well revealed similar detections of PCE (1.9 μg/L), TCE (0.62 μg/L), and cis-1,2-DCE (0.66 μg/L) 

[Ref. 7, pp. 5, 7; 8, pp. 1-34, 69-70, 251; 9, p. 10]. Ground water sample CR-GW06, which was collected from the Club 

de Leones well, indicated the presence of 1,1-DCE at 0.96 μg/L [Ref. 7, p. 5; 8, p. 1-34, 57, 252; 9, p. 10]. Chlorinated 

solvents were not detected in any other ground water samples collected in July 2006, including ground water samples 

CR-GW02 and CR-GW03, collected from public supply wells Cabo Rojo 2 and Cabo Rojo 3, respectively [Ref. 7, pp. 5, 

7; 8, pp. 1-34, 42-80, 248-250; 9, pp. 7-17; 32, p. 6]. Ground water samples CR-GW02 and CR-GW03 indicated nondetect values for PCE, TCE, cis-1,2-DCE, and 1,1-DCE; therefore those samples were chosen to demonstrate background 

ground water conditions [Ref. 7, pp. 5, 7; 8, pp. 1-34, 45-46, 48-49, 250; 9, p. 10; 32, p. 6]. 

Hazardous 

Substance Evidence CRQL* (μg/L) Reference(s) 

PCE CR-GW04 (1.9 μg/L) 

 CR-GW14 (1.9 μg/L) 

CR-GW02 (0.50 U)** 

CR-GW03 (0.50 U)** 

0.50 

0.50 

0.50 

0.50 

8, pp. 52, 251 

8, pp. 70, 251 

8, pp. 2, 46, 250 

8, pp. 2, 49, 250 

TCE CR-GW04 (0.63 μg/L) 

 CR-GW14 (0.62 μg/L) 

CR-GW02 (0.50 U)** 

CR-GW03 (0.50 U)** 

0.50 

0.50 

0.50 

0.50 

8, pp. 52, 251 

8, pp. 70, 251 

8, pp. 2, 46, 250 

8, pp. 2, 49, 250 

Cis-1,2-DCE CR-GW04 (0.67 μg/L) 0.50 8, pp. 51, 251 

 CR-GW14 (0.66 μg/L) 0.50 8, pp. 69, 251 

CR-GW02 (0.50 U)** 0.50 8, pp. 2, 45, 250 

15 
 

 

 

 

SD- Hazardous Substances 

Source No.: 1 

CR-GW03 (0.50 U)** 0.50 8, pp. 2, 48, 250 

1,1-DCE CR-GW06 (0.96 μg/L) 

CR-GW02 (0.50 U)** 

CR-GW03 (0.50 U)** 

0.50 

0.50 

0.50 

8, pp. 57, 252 

8, pp. 2, 45, 250 

8, pp. 2, 48, 250 

U - The analyte was analyzed for, but was not detected at a level greater than or equal to the level of the 

 adjusted CRQL for sample and method [Ref. 8, p. 2; 32, p. 6] 

* - The sample analyses were performed under the EPA Contract Laboratory Program (CLP), and the Sample 

 Quantitation Limits (SQL) are not established; therefore, the CRQLs are used in place of the SQLs to 

establish the observed release [Ref. 1, p. 51589; 33, p. 8] 

** - background concentration 

EPA Sampling Event – Ground Water Samples: September 2009 

EPA collected five ground water samples from four PRASA-operated public supply wells in September 2009 [Ref. 14, 

pp. 4-5; 15, pp. 3-4, 6, 8; 16, p. 25]. The samples were analyzed for TCL VOCs through the EPA CLP [Ref. 15, pp. 3, 8; 

16, pp. 1-19]. Samples CRGC-GW01 and CRGC-GW02 were collected from the Ana Maria well, sample CRGC-GW03 

was collected from the Club de Leones well, and designated background samples CRGC-GW04 and CRGC-GW05 were 

collected from the Cabo Rojo 2 and Cabo Rojo 3 wells, respectively [Ref. 14, pp. 4-5; 15, pp. 4, 6; 16, p. 25]. EPA 

validated the trace VOCs data according to SOP HW-34 (Revision 0), “USEPA Region II Data Validation SOP for 

Statement of Work SOM01.1” [Ref. 16, pp. 1, 20-24]. EPA found the VOC data to be valid and acceptable, including 

meeting the CRQL requirements [Ref. 16, pp. 1, 20-24]. 

Hazardous 

Substance Evidence CRQL* (μg/L) Reference(s) 

PCE CRGC-GW01 (1.1 μg/L) 0.50 16, pp. 3, 25 

 CRGC-GW02 (1.1 μg/L) 0.50 16, pp. 6, 25 

CRGC-GW04 (0.50 U)** 0.50 16, pp. 15, 20, 25 

CRGC-GW05 (0.50 U)** 0.50 16, pp. 18, 20, 25 

U - The analyte was analyzed for, but was not detected at a level greater than or equal to the level of the 

 adjusted CRQL for sample and method [Ref. 16, p. 20; 32, p. 6]. 

* - The sample analyses were performed under the EPA CLP, and the SQLs are not established; therefore, the 

 CRQLs are used in place of the SQLs to establish the observed release [Ref. 1, p. 51589; 33, p. 8] 

** - background concentration 

16 
 

 

 

 

 

SD-Hazardous Waste Quantity 

Source No.: 1 

2.4.2 Hazardous Waste Quantity 

2.4.2.1.1 Hazardous Constituent Quantity 

The information available is not sufficient to evaluate Tier A source hazardous waste quantity; therefore, hazardous 

constituent quantity is not scored (NS). 

Hazardous Constituent Quantity (C) Value: NS 

2.4.2.1.2 Hazardous Wastestream Quantity 

The information available is not sufficient to evaluate Tier B source hazardous waste quantity; therefore, hazardous 

wastestream quantity is not scored. 

Hazardous Wastestream Quantity (W) Value: NS 

2.4.2.1.3 Volume 

Because there are wells with samples showing contamination in the ground water but the volume of the contaminated 

area has not been determined, the volume of the ground water contamination is considered to be greater than 0 cubic 

yards but unknown [Ref. 8, pp. 51-52, 57; 16, pp. 2-3, 5-6, 11]. Therefore, volume (V) is assigned a value of >0 but 

unknown [Ref. 1, p. 51591]. 

Dimension of source (yd3

): >0 

Volume (V) Assigned Value: >0 

2.4.2.1.4 Area 

2.4.2.1.5 

Tier D, Are

Source Hazardous Waste Quantity Value 

a is not evaluated for source type “Other” [Ref. 1, p. 51591; Table 2-5]. 

Area of source (ft2

): N/A 

Area (A) Assigned Value: 0 

The source hazardous waste quantity value for Source 1 is >0 but unknown for Tier C - Volume [Ref. 1, p. 51591]. 

Source Hazardous Waste Quantity Value: >0 

17 
 

SD-Summary 

SITE SUMMARY OF SOURCE DESCRIPTIONS 

Source Containment 

Source Hazardous Waste Ground Surface Air 

Number Quantity Value Water Water Gas Particulate 

1 >0 10 NS NS NS 

NS = Not Scored 

18 
 

 

 

 

GW-General 

3.0 GROUND WATER MIGRATION PATHWAY 

3.0.1 General Considerations 

The Cabo Rojo Ground Water Contamination site is located within the east-southeast trending Guanajibo River Valley, 

one of the largest of a series of alluvial valleys that occur within the West Coast (ground water) Province [Ref. 28, pp. 

14, 21]. The vertical sequence of stratigraphic units within the Guanajibo Valley includes unconsolidated alluvial (sand, 

gravel, and clayey sand) and marginal marine deposits underlain by limestone and volcaniclastic igneous bedrock [Ref. 

28, pp. 21, 23; 30, pp. 14-15]. The transmissivity associated with the Ana Maria well is 1,400 square feet per day 

(ft2

/day) and the transmissivity of the Club de Leones well is 1,300 ft2/day [Ref. 30, pp. 5, 10, 22]. In addition, the 

hydraulic conductivity associated with the Ana Maria well is 3.08 x 10-3 centimeters per second (cm/sec) and the 

hydraulic conductivity associated with the Club de Leones well is 7.64 x 10-3 cm/sec [Ref. 30, pp. 5, 10, 22; 61, p. 1]. 

PRASA supply wells associated with the Cabo Rojo Ground Water Contamination site (i.e., Ana Maria, Club de Leones, 

Cabo Rojo 2, and Cabo Rojo 3) are finished in the bedrock aquifer [Ref. 30, pp. 9-10, 15]. 

Geologic cross-sections for the Cabo Rojo region published by the U.S. Geological Survey (USGS), confirm that there is 

not a continuous confining layer separating the alluvial valley aquifer and the bedrock aquifer within 2 miles of the 

ground water plume; therefore, the alluvium and bedrock aquifers are evaluated as one hydrogeologic unit [Ref. 1, p. 

51595; 30, pp. 9, 15-16]. Furthermore, as stated above, the hydraulic conductivity of the limestone and volcaniclastic 

igneous bedrock are similar [Ref. 1, p. 51595, 51601; 30, pp. 5, 10, 22; 61, p. 1]. The direction of ground water flow in 

the vicinity of the site is influenced by a cone of depression toward public supply wells (i.e., Cabo Rojo 2, Cabo Rojo 3, 

and Club de Leones) located in the vicinity of the low-lying Cienaga de Cuevas/Bajura area [Figure 2; Ref. 4, p. 1; 30, 

pp. 7- 10, 16-17]. 

Ana Maria, Club de Leones, Cabo Rojo 2, and Cabo Rojo 3 are all finished in the bedrock aquifer [Ref. 30, pp. 9-10, 15]. 

Bottom elevations of the wells range from 143 to 236 feet above mean sea level (AMSL), and the screened intervals 

presented range in elevation from 33 to 236 feet AMSL; however the pump depths for the wells are similar (133-149 feet 

AMSL) [Ref. 13, pp. 1, 11, 13; 30, p. 10]. The interconnected water supply system consisting of Hacienda la Margarita, 

Cabo Rojo 1, Cabo Rojo 2, Cabo Rojo 3, and Club de Leones serve an estimated population of 45,055 people [Ref. 6, pp. 

1, 3]. The Ana Maria well acts as an independent system which serves approximately 1,856 persons [Ref. 6, pp. 1-2]. 

Wellhead Protection Areas are delineated for the contaminated public supply wells, so the plume lies within a designated 

Wellhead Protection Area [Ref. 10, pp. 32-48; 11, p. 1; 59, p.1]. 

19 
GW-General 

Stratum 1 (shallowest) 

Stratum Name: Alluvium 

Description: The alluvium in the Guanajibo River Valley consists of Quaternary-age gravels, sands, and clayey sands 

[Ref. 30, p. 6]. The thickness of these deposits in the Guanajibo Valley is reported to be as much as 105 feet [Ref. 29, p. 

11]. Ground water exists under water-table conditions and recharges the underlying bedrock [Ref. 30, p. 16]. 

Stratum 2/Aquifer 

Stratum/Aquifer Name: Igneous and Limestone Bedrock 

Description: The bedrock underlying the alluvium consists of the Cretaceous-age Cotuí Limestone and undifferentiated 

igneous and volcaniclastic rocks [Ref. 28, p. 21; 30, pp. 6, 15]. Ground water exists under water-table conditions and is 

recharged from the overlying intergranular surficial deposits (i.e., the alluvium) [Ref. 30, p. 16]. Ground water 

movement is towards a cone of depression produced by the pumping of water supply wells Cabo Rojo 2, Cabo Rojo 3, 

and Club de Leones [Ref. 30, pp. 10, 16-17]. 

20 
 

 

 

 

 

 

GW-Observed Release 

3.1 LIKELIHOOD OF RELEASE 

3.1.1 Observed Release 

Aquifer Being Evaluated: Bedrock aquifer 

An observed release is documented for the Cabo Rojo Ground Water Contamination site. Chemical analyses for ground 

water samples collected from the Ana Maria and Club de Leones public supply wells in 2006 and 2009 show the 

continuing presence of chlorinated solvents [Ref. 7, p. 5; 8, pp. 51-52, 57, 69-70; 9, p. 10; 14, p. 5; 15, p. 4; 16, pp. 3, 6, 

11]. 

All background and contaminated samples documenting the observed release were collected from the aquifer being 

evaluated (i.e., Ana Maria and Club de Leones wells are all finished in the same hydrologic unit (i.e., the bedrock 

aquifer) [Ref. 30, pp. 7-16]. Samples from the Cabo Rojo 2 and Cabo Rojo 3 wells are evaluated as representative of 

background conditions due to similar pump depths to the wells where observed releases occurred [Ref. 13, pp. 1, 4, 13; 

14, p. 3]. The chlorinated solvents found in the release wells are not naturally occurring, and the non-detect 

concentrations in background wells Cabo Rojo 2 and Cabo Rojo 3 show that the compounds are not ubiquitous in the 

area [Ref. 8, pp. 45-46, 48-49; 16, pp. 14-15, 17-18]. The background samples from Cabo Rojo 2 and Cabo Rojo 3 were 

collected within the same general timeframe as the release samples from Ana Maria and Club de Leones (July 2006 and 

September 2009) [Ref. 7, p. 5; 9, p. 10; 14, p. 5; 15, p. 4]. 

Chemical Analysis 

EPA Sampling Event – Ground Water Samples: July 2006 

In July 2006, EPA collected ten ground water samples from nine PRASA-operated public supply wells, three ground 

water samples from three private wells, and pre- and post-treatment aqueous samples from the Boqueron Filtration Plant 

[Ref. 7, pp. 3-5, 9-15, 18-21; 9, pp. 7-17]. Chain of custody of the samples was maintained throughout sample shipping, 

collection, and analysis [Ref. 8, pp. 1, 243-257; 16, pp. 1, 25]. The samples were analyzed for TCL and TAL parameters 

through the EPA CLP [Ref. 7, p. 4; 8, p. 1]. Samples CR-GW04 and CR-GW14 were collected from the Ana Maria well, 

sample CR-GW06 was collected from the Club de Leones well, and background samples CR-GW02 and CR-GW03 were 

collected from Cabo Rojo 2 and Cabo Rojo 3, respectively [Ref. 7, p. 5; 9, pp. 7-17]. EPA validated the trace VOCs data 

according to SOP HW-34 (Revision 0), “USEPA Region II Data Validation SOP for Statement of Work SOM01.1” [Ref. 

8, pp. 2-31]. EPA found the VOC data to be valid and acceptable, including meeting the CRQL requirements [Ref. 8, pp. 

2-31]. 

EPA Sampling Event – Ground Water Samples: September 2009 

EPA collected five ground water samples from four PRASA-operated public supply wells in September 2009 [Ref. 14, 

pp. 4-5; 15, pp. 3-4, 8]. The samples were analyzed for TCL VOCs through the EPA CLP [Ref. 14, p. 4; 15, pp. 3, 8; 16, 

p. 20]. Samples CRGC-GW01 and CRGC-GW02 were collected from the Ana Maria well, sample CRGC-GW03 was 

collected from the Club de Leones well, and designated background samples CRGC-GW04 and CRGC-GW05 were 

collected from Cabo Rojo 2 and Cabo Rojo 3, respectively [Ref. 14, pp. 4-5; 15, p. 4]. EPA validated the trace VOCs 

data according to SOP HW-34 (Revision 0), “USEPA Region II Data Validation SOP for Statement of Work SOM01.1” 

[Ref. 16, pp. 20-24]. EPA found the VOC data to be valid and acceptable, including meeting the CRQL requirements 

[Ref. 16, pp. 20-24]. 

21 
 

 

 

 

 

 

 

GW-Observed Release 

Background Concentrations (Public Supply Wells) 

EPA Sampling Events – Ground Water Samples: July 2006 and September 2009

Well Location 

 Screened Interval 

(ft AMSL) Sample ID 

Sample 

Date Reference(s) 

Cabo Rojo 2 33 to 143** CR-GW02 (B3S25) 

CRGC-GW04 (B5Q97) 

07/12/06 

09/02/09 

7, p. 5; 8, p. 250; 9, p. 10; 

13, p. 1 

14, p. 4; 15, p. 4; 16, p. 25 

Sample ID Hazardous Substance Conc. (μg/L) CRQL* (μg/L) Reference(s) 

CR-GW02 PCE 

TCE 

cis-1,2-DCE 

1,1-DCE 

0.50 U 

0.50 U 

0.50 U 

0.50 U 

0.50 

0.50 

0.50 

0.50 

8, pp. 2, 46 

8, pp. 2, 46 

8, pp. 2, 45 

8, pp. 2, 45 

CRGC-GW04 PCE 

1,1-DCE 

0.50 U 

0.50 U 

0.50 

0.50 

16, pp. 15, 20 

16, pp. 14, 20 

Well Location 

 Screened Interval 

(ft AMSL) Sample ID 

Sample 

Date Reference(s) 

Cabo Rojo 3 33 to 143** CR-GW03 (B3S26) 

CRGC-GW05 (B5Q98) 

07/12/06 

09/02/09 

7, p. 5; 8, p. 250; 9, p. 10; 

13, p. 1 

14, p. 5; 15, p. 4; 16, p. 25 

Sample ID Hazardous Substance Conc. (μg/L) CRQL* (μg/L) Reference(s) 

CR-GW03 PCE 

TCE 

cis-1,2-DCE 

1,1-DCE 

0.50 U 

0.50 U 

0.50 U 

0.50 U 

0.50 

0.50 

0.50 

0.50 

8, pp. 2, 49 

8, pp. 2, 49 

8, pp. 2, 48 

8, pp. 2, 48 

CRGC-GW05 PCE 

1,1-DCE 

0.50 U 

0.50 U 

0.50 

0.50 

16, pp. 18, 20 

16, pp. 17, 20 

U - The analyte was analyzed for, but was not detected at a level greater than or equal to the level of the 

 adjusted CRQL for sample and method [Ref. 8, pp. 2, 45-49; 16, pp. 14-18, 20; 32, p. 6] 

* - The sample analyses were performed under the EPA CLP, and the SQLs are not established; therefore, the 

 CRQLs are used in place of the SQLs to establish the observed release [Ref. 1, p. 51589; 33, p. 8] 

** - The screened depths are unknown; therefore, the maximum possible screened interval is presented [Ref. 

13, p. 1] 

22 
 

 

 

 

 

 

 

GW-Observed Release 

Contaminated Samples (Public Supply Wells) 

EPA Sampling Event – Ground Water Samples: July 2006 and September 2009

 Screened Interval Sample 

Well Location (ft AMSL) Sample ID Date Reference(s) 

Ana Maria 36 to 236 CR-GW04 (B3S27) 07/12/06 7, p. 5; 8, p. 251; 9, p. 10; 

13, p. 1 

CR-GW14 (B3S37) 07/12/06 7, p. 5; 8, p. 251; 9, p. 10 

CRGC-GW01 (B5Q93) 09/02/09 14, p. 5; 15, p. 4; 16, p. 25 

CRGC-GW02 (B5Q94) 09/02/09 14, p. 5; 15, p. 4; 16, p. 25 

Sample ID Hazardous Substance Conc. (μg/L) CRQL* (μg/L) Reference(s) 

CR-GW04 PCE 1.9 0.50 8, p. 52 

TCE 0.63 0.50 8, p. 52 

cis-1,2-DCE 0.67 0.50 8, p. 51 

CR-GW14 PCE 1.9 0.50 8, p. 70 

TCE 0.62 0.50 8, p. 70 

cis-1,2-DCE 0.66 0.50 8, p. 69 

CRGC-GW01 PCE 1.1 0.50 16, p. 3 

CRGC-GW02 PCE 1.1 0.50 16, p. 6 

 Screened Interval Sample 

Well Location (ft AMSL) Sample ID Date Reference(s) 

Club de Leones 39 to 189 CR-GW06 (B3S29) 07/12/06 7, p. 5; 8, p. 251; 9, p. 10; 

13, p. 1 

Sample ID Hazardous Substance Conc. (μg/L) CRQL* (μg/L) Reference(s) 

CR-GW06 1,1-DCE 0.96 0.50 8, p. 57 

* - The sample analyses were performed under the EPA CLP, and the SQLs are not established; therefore, the 

 CRQLs are used in place of the SQLs to establish the observed release [Ref. 1, p. 51589; 33, p. 8] 

23 
 

 

 

 

GW-Observed Release 

Attribution: 

In 2006, EPA launched the Cabo Rojo Site Discovery Initiative in order to identify potential hazardous waste sites in the 

vicinity of contaminated wells in Cabo Rojo [Ref. 26, p. 2]. During the initial phase of the Cabo Rojo Site Discovery 

Initiative, EPA collected ground water samples from seven public supply wells located in Cabo Rojo (Hacienda la 

Margarita, Cabo Rojo 1, Cabo Rojo 2, Cabo Rojo 3, Club de Leones, Ana Maria, and Remanzo), three privately owned 

wells (Lighthouse Tropical Inn, Mariola Bottled Water facility, and Schoenstatt Convent), and two wells from a 

neighboring PRASA system (Pozo III/Javieres and Pozo II /Hormigueros) [Ref. 7, pp. 3-7; 9, pp. 7-16]. A review of the 

analytical results confirmed the presence of chlorinated solvents in the Ana Maria and Club de Leones wells; chlorinated 

solvents were not detected in any of the other wells sampled [Ref. 7, p. 5; 8, pp. 42-86]. 

In order to initiate the task of identifying hazardous waste sites in the vicinity of confirmed ground water contamination, 

EPA conducted file searches at the offices of the Puerto Rico Environmental Quality Board (PREQB) and Puerto Rico 

Industrial Development Company (PRIDCO) to obtain information regarding hazardous waste storage practices and 

hazardous waste releases [Ref. 26, p. 2]. EPA also conducted an Internet search for listings of dry cleaning and 

automobile repair facilities in and around Cabo Rojo [Ref. 26, p. 2]. Based on the file and Internet searches, EPA 

compiled a complete list of facilities at which to conduct site reconnaissance activities [Ref. 26, p. 2]. In November and 

December 2006 EPA conducted site reconnaissance activities at 68 facilities within the municipality of Cabo Rojo [Ref. 

9, pp. 18-40, 43-61; 26, pp. 8-33]. As a result of the Site Discovery Initiative, EPA identified fifteen facilities that 

required further investigation [Ref. 26, p. 34; 37, p. 1]. The 53 remaining facilities were mainly gas or service stations or 

retail facilities where there was evidence of use of only non-chlorinated substances, primarily excluded petroleum 

products [Ref. 26, pp. 8-33]. The fifteen facilities requiring further investigation were: four abandoned facilities where 

uncontained waste sources possibly exist, three dry cleaning facilities that use or were suspected of using chlorinated 

solvents, six mechanic shops where poor housekeeping or the usage of chlorinated solvents was observed or suspected, 

and two painting/print shops with partial outdoor operations and usage of chlorinated solvents [Ref. 26, pp. 8, 10-15, 20-

22, 25-28]. 

In January 2007, EPA conducted source investigations at the fifteen facilities in Cabo Rojo identified as potential sources 

of the ground water contamination [Ref. 37, p.1]. These investigations included the completion of fourteen Preliminary 

Assessment/Site Inspections (PA/SI); the location of one of the facilities (i.e., PRIDCO) was not confirmed and a PA/SI 

could not be conducted [Ref. 37, p.1]. Of the fourteen facilities where PA/SI level investigations were completed, twelve 

investigations included collection of surface and subsurface soil and ground water samples [Ref. 37, p.1]. EPA collected 

a total of 61 surface soil samples, 66 subsurface soil samples, and 28 ground water samples from twelve facilities in an 

effort to identify potential sources of ground water contamination [Ref.18, pp. 3-5; 21, pp. 3, 5-6; 24, pp. 3-6; 38, pp. 3-4; 

40, pp. 3-7; 42, pp. 3, 5; 45, pp. 3-7; 47, pp. 3-7; 49, pp. 3-7; 52, pp. 3, 5; 54, pp. 3-5; 56, pp. 3-7]. Samples collected 

from nine of these facilities did not indicate the presence of chlorinated solvents in soil or ground water samples [Ref. 39, 

pp. 35-58; 41, pp. 37-93; 43, pp. 27-60; 44, pp. 117-122; 46, pp. 38-48, 202-246; 48, pp. 165-212; 50, pp. 30-59; 51, pp. 

41-52; 53, 146-166; 55, pp. 41-61; 57, pp. 119-163]. Chlorinated solvents (i.e., PCE, TCE, cis-1,2-DCE, trans-1,2-DCE, 

and vinyl chloride) were detected at the three remaining facilities [Ref. 19, pp. 13-14, 34-35, 37-38; 22, pp. 39, 42, 45; 

25, pp. 9, 18, 21]. 

No facility in the immediate area of either the Ana Maria well or Club de Leones well had VOC contamination detected 

in both soil and ground water samples [Figure 2]. At the Extasy Q Prints (EQP) facility, ground water samples indicated 

the presence of PCE; however, there were no VOCs detected in surface or subsurface soil samples [Figure 2; Ref. 20, pp. 

15-17; 21, pp. 6, 9; 22, pp. 39, 42, 45, 47-87]. At another nearby facility, Cabo Rojo Professional Dry Cleaners 

(CRPDC), surface and subsurface soil samples indicated the presence of PCE; however, PCE was not detected in the 

ground water samples [Figure 2; Ref. 23, p. 17; 24, pp. 4-5; 25, pp. 9, 18, 21, 27-37; 32, p. 6]. Conversely, both soil and 

ground water samples collected from the D’Elegant Fantastic Dry Cleaners (DFDC) facility indicated the presence of cis1,2-DCE, TCE and PCE; however, the facility is not in close proximity to the Ana Maria well (i.e., the DFDC facility is 

located approximately 4,600 feet southwest of the well) and the CRPDC facility is located between the well and that 

facility [Figure 2; Ref. 18, pp. 4-5; 19, pp. 13-14, 34-35, 37-38]. Based on these considerations, the ground water 

contamination observed in the two public supply wells (i.e., Ana Maria and Club de Leones); is not known to be 

attributable to any specific source(s). 

Descriptions of the three aforementioned facilities, including the results of the PA/SI investigations, are provided below: 

24 
 

 

 

 

 

 

 

 

GW-Observed Release 

1. Extasy Q Prints 

The EQP facility is located in the Centro Comercial Ana Maria strip mall [Ref. 20, p. 9]. The facility is located in a 

mixed commercial/residential area and consists of a portion of a concrete building [Ref. 20, p. 12, 26, 28. The strip mall 

houses other business, including a day care center, a pizzeria, and an electronics company [Ref. 20, p. 29]. A review of 

regulatory files and databases did not disclose any history of releases or other environmental concerns [Ref. 20, p. 12]. 

Current operations at the facility consist of printing T-shirts, towels, and bags with varying designs [Ref. 20, p. 4]. The 

machinery used in the printing process is cleaned with water, petroleum-based cleaners, and rags [Ref. 20, pp. 4, 12]. 

Screens used in the printing process are possibly cleaned with liquids that contain VOCs, including PCE [Ref. 20, pp. 4, 

12]. EQP has been in operation at this location since approximately 1986 [Ref. 20, p. 4]. 

On December 1, 2006 and April 4, 2007, EPA conducted site reconnaissance activities at the EQP facility [Ref. 20, pp. 4-

5, 9-11]. EPA observed that outdoor screen washing practices, where wash solutions enter a sink, discharges to the 

ground [Ref. 20, pp. 4, 47-48]. The wash area is multi-colored from washing paints from the screens [Ref. 20, pp. 47]. 

On June 19 and 20, 2007, EPA conducted a sampling event at the EQP facility [Ref. 20, pp. 14-23, 51-55]. During this 

event, EPA collected surface soil, subsurface soil, and ground water samples from borings advanced using direct-push 

technology [Ref. 20, pp. 15-23]. Samples were analyzed for TCL VOCs through the EPA CLP [Ref. 20, pp. 18-19; 21, 

pp. 3, 12-14; 22. pp. 1-32]. Analytical results from this sampling event indicated detections of VOCs in ground water 

samples; there were no detections of VOCs in surface or subsurface soil samples [Ref. 22, pp. 47-88]. Ground water 

samples EQP-GW04, EQP-GW05, and EQP-GW06 indicated the presence of PCE (8.9 μg/L, 14 μg/L, and 13 μg/L, 

respectively) in ground water samples from two boreholes advanced between the EQP facility and the Ana Maria well 

[Ref. 20, pp. 15-17; 21, pp. 6, 9; 22, pp. 39, 42, 45]. 

2. Cabo Rojo Professional Dry Cleaners 

The CRPDC facility consists of a single-story building and a paved parking lot with a few small areas of exposed soil 

and vegetation [Ref. 23, pp. 25, 37]. The site is located in a mixed commercial/residential area in the town of Cabo Rojo 

[Ref. 23, p. 24]. CRPDC is a privately owned and operated family business [Ref. 23, p. 6]. The history of the facility 

before CRPDC began operating in approximately 1987 is unknown [Ref. 23, p. 7]. A review of regulatory files and 

databases did not disclose any history of releases or other environmental concerns [Ref. 23, p. 15]. 

On November 29, 2006 and April 4, 2007, EPA conducted site reconnaissance activities at the CRPDC facility [Ref. 23, 

pp. 4, 6-7, 13-16]. Current operations at the facility include laundry and dry cleaning [Ref. 23, p. 6]. CRPDC uses PCE 

solvent in its dry-cleaning operation and generates PCE-contaminated sludge as a waste material [Ref. 23, pp. 6-8]. The 

facility is registered as a hazardous waste handler (EPA ID No. PRR000013433) [Ref. 34, p. 1]. 

EPA conducted a sampling event at and in the vicinity of the CRPDC site on June 20 and 22, 2007 [Ref. 23, pp. 16-21, 

30-35, 42-45; 24, p. 3]. During this event, surface soil, subsurface soil, and ground water samples were collected from 

borings advanced using direct-push technology and manually using a stainless-steel auger [Ref. 23, pp. 16-21, 30-35, 42-

45; 24, p. 3]. Samples were analyzed for TCL VOCs through the EPA CLP [Ref. 24, pp. 2, 11-12, 14; 25, pp. 50-85. 

Analytical results from this sampling event indicated the presence of VOCs in surface soil and subsurface soil samples 

[Ref. 25, pp. 9, 18, 21]. Surface soil samples CRPDC-S02 and CRPDC-S03 indicated the presence of PCE (23 μg/kg 

and 29 μg/kg, respectively) and subsurface soil sample CRPDC-SS10 indicated an estimated concentration of PCE (73 J 

μg/kg) [Ref. 23, p. 17; 24, pp. 4-5; 25, pp. 9, 18, 21; 32, p. 6]. The site-related chlorinated solvent, PCE, was detected at 

only trace amounts (i.e., below the CRQL) in ground water samples collected at the CRPDC facility [Ref. 24, pp. 5, 6; 

25, pp. 26-36]. 

3. D’Elegant Fantastic Dry Cleaners 

The DFDC facility is located in the southern portion of the Centro Commercial La 100 strip mall , outside the immediate 

area of the Ana Maria and Club de Leones wells [Figures 1 and 2; Ref. 17, p. 6, 25, 27]. In addition to the DFDC 

facility, the strip mall has two restaurants, a hair salon, a bakery, three empty units, and is surrounded by asphalt with 

parking areas on the northern and eastern side [Ref. 17, p. 27]. Current and historical operations include dry cleaning and 

25 
 

GW-Observed Release 

spot cleaning of clothing [Ref. 17, pp. 6, 7]. The dry cleaning and spot cleaning operations use Dowper, commonly 

referred to as PCE, and Tar Go Dry, a product that contains multiple VOCs, including TCE [Ref. 17, pp. 6, 8]. 

DFDC has been in operation at this location since 2005 [Ref. 17, p. 6]. Previously, Modern Man Dry Cleaning operated 

at this location under Resource Conservation and Recovery Act (RCRA) Permit ID No. PRN008009185 [Ref. 17, p. 6; 

35, p. 1; 36, pp. 1-2]. The owner of DFDC indicated that Modern Man Dry Cleaning was in operation for many years; 

however, the exact duration of operation is unknown [Ref. 17, pp. 6, 7] The DFDC CERCLA ID No. and Modern Man 

Cleaners RCRA Permit ID No. are the same [Ref. 35, p. 1; 36, p. 2]. 

On November 29, 2006 and April 4, 2007, EPA conducted site reconnaissance activities of the DFDC facility 

accompanied by DFDC personnel [Ref. 17, pp. 4, 6-7, 16-17, 25-29]. An empty 55-gallon PCE drum was being stored 

outside the side door of the facility on a concrete pad [Ref. 17, pp. 16, 28]. All storage and work areas were observed to 

be in good condition with no apparent spills or discharges [Ref. 17, p. 28]. EPA observed that there are no monitoring 

wells at the site [Ref. 17, p. 7]. 

On June 15, 2007, EPA conducted a sampling event at the DFDC facility [Ref. 17, pp. 20-23; 43-44]. During this event, 

EPA personnel collected surface soil, subsurface soil, and ground water samples from borings advanced using directpush technology [Ref. 17, pp. 20-23; 43-44; 18, pp. 3, 10; 19, pp. 1-8]. Samples were analyzed for TCL VOCs through 

the EPA CLP [Ref. 19, p. 9]. Analytical results from this sampling event indicated detections of VOCs in soil and 

ground water samples [Ref. 18, pp. 4-5; 19, pp. 13-14, 34-35, 37-38]. Trans-1,2-DCE (29 micrograms per kilogram) 

(μg/kg), cis-1,2-DCE (230 J μg/kg), TCE (130 μg/kg), and PCE (36 μg/kg) were detected in soil sample DFDC-S02, 

collected just outside the side door of the operations portion of the facility [Ref. 17, pp. 21, 33-34, 43; 18, p. 4; 19, pp. 

13-14; 32, p. 6]. In addition, ground water samples DFDC-GW02 and DFDC-GW03 collected from the same borehole 

location indicated the presence of cis-1,2-DCE (310 μg/L), TCE (68 μg/L) and PCE (67 μg/L) [Ref. 17, pp. 21-23, 44; 

18, p. 5; 19, pp. 34-35]. Although both soil and ground water samples collected from the DFDC facility indicated the 

presence of cis-1,2-DCE, TCE and PCE, the facility is not in close proximity to the Ana Maria well (i.e., the DFDC 

facility is located approximately 4,600 feet southwest of the well) [Figure 2; Ref. 18, pp. 4-5; 19, pp. 13-14, 34-35, 37-

38]. The CRPDC facility is located between the Ana Maria well and the DFDC facility, and ground water samples 

collected at the CRPDC facility did not indicate the presence of site-related chlorinated solvents at higher than trace 

levels (i.e., if detected, were detected below the CRQL [Figure 2; Ref. 24, pp. 5, 6; 25, pp. 26-36]. 

26 
GW-Observed Release 

Hazardous Substances Released: 

Tetrachloroethylene (PCE) CAS No. 000127-18-4 

Trichloroethylene (TCE) CAS No. 000079-01-6 

cis-1,2-Dichloroethylene (cis-1,2-DCE) CAS No. 000156-59-2 

1,1-Dichloroethylene (1,1-DCE) CAS No. 000075-35-4 

================================================================================= 

 Ground Water Observed Release Factor Value: 550 

27 
 

 

 

GW-Toxicity/Mobility 

3.2 WASTE CHARACTERISTICS 

3.2.1 Toxicity/Mobility 

Hazardous Source Toxicity Mobility Toxicity/ 

Substance Numbers Factor Value Factor Value Mobility Reference(s) 

Tetrachloroethylene 1, OR 100 1.0 100 2, p. 15 

Trichloroethylene 1, OR 10,000 1.0 10,000 2, p. 57 

cis-1,2-Dichloroethylene 1, OR 100 1.0 100 2, p. 10 

1,1-Dichloroethylene 1, OR 100 1.0 100 2, p. 10 

OR = Observed Release 

================================================================================== 

Toxicity/Mobility Factor Value: 10,000 

28 
 

 

GW-Waste Characteristics 

3.2.2 Hazardous Waste Quantity 

Source Hazardous Is source hazardous 

Waste Quantity (HWQ) constituent quantity 

Source Number Value (Section 2.4.2.1.5) data complete? (yes/no) 

1 >0 No 

Sum of Values: >0 (rounded to nearest integer as specified in HRS Section 2.4.2.2) 

The sum corresponds to a hazardous waste quantity factor value of 1 in Table 2-6 of the HRS [Ref. 1, p. 51591]. 

However, based on the fact that the source hazardous constituent quantity has not been adequately determined and that 

targets are subject to Level I and Level II concentrations (see Section 3.3.2.3 of this document), a hazardous waste 

quantity factor value of 100 can be assigned if it is greater than the hazardous waste quantity value from Table 2-6 (i.e., 

1) [Ref. 1, pp. 51591- 51592]. Therefore, a hazardous waste quantity factor value of 100 is assigned for the ground water 

pathway. 

3.2.3 Waste Characteristics Factor Category Value 

TCE corresponds to the toxicity/mobility factor value of 10,000, as shown previously (see Section 3.2.1). 

Toxicity/Mobility Factor Value (10,000) x Hazardous 

Waste Quantity Factor Value (100): 1 x 106 

The product (1 x 106

) corresponds to a Waste Characteristics Factor Category Value of 32 in Table 2-7 of the HRS [Ref. 

1, p. 51592]. 

1,1-DCE corresponds to the toxicity/mobility factor value of 100, as shown previously (see Section 3.2.1). 

Toxicity/Mobility Factor Value (100) x Hazardous 

Waste Quantity Factor Value (100): 1 x 104 

The product (1 x 104

) corresponds to a Waste Characteristics Factor Category Value of 10 in Table 2-7 of the HRS [Ref. 

1, p. 51592]. 

================================================================================== 

Hazardous Waste Quantity Factor Value: 100 

Waste Characteristics Factor Category Value: 32 

29 
 

 

GW-Targets 

3.3 TARGETS 

There are six active wells (Hacienda la Margarita, Cabo Rojo 1, Cabo Rojo 2, Cabo Rojo 3, Club de Leones, and Ana 

Maria) and one surface water source in the Cabo Rojo Urbano system [Ref. 6, p. 1]. The Ana Maria well is a separate 

single component that serves 680 houses. Therefore, the population served by the Ana Maria well is calculated, and 

subsequently rounded as follows: 

680 households x 2.73 persons/household = 1,856.4 = 

1,856 persons served by the Ana Maria well [Ref. 6, p. 1]. 

The remaining five wells (all wells listed except Ana Maria) and surface water intake at a filtration plant are combined to 

serve the town of Cabo Rojo [Ref. 6, p. 1]. The relative contributions of each input to the Cabo Rojo Urbano system, 

ranging from 0.625 to 1.5 million gallons per day (MGD), are less than 40% (i.e., 2 MGD); therefore, the HRS states that 

the relative contribution of each component can be considered equal [Ref. 1, p. 51603; 6, pp. 1, 3]. 

After subtracting the population served by the Ana Maria well the total population of the system is divided by the total 

number of inputs [Ref. 6, p. 1]. The population served by the Club de Leones well is calculated, and subsequently 

rounded as follows: 

46,911 total population - 1,856 persons served by Ana Maria = 45,055 people 

(5 wells + 1 surface water source) = 6 

45,055 / 6 = 7,509.1 

= 7,509 persons served by the Club de Leones well [Ref. 6, p. 1] 

The populations and levels of contamination are presented below: 

Distance Level I Level II Potential 

from Contam. Contam. Contam. 

Well Source (mi.)* Population (Y/N)** (Y/N)** (Y/N) Reference(s) 

Ana Maria 0 1,856 Y N N [Fig. 1; Ref. 1, pp. 

51593, 51595, 51603; 

6, p. 1] 

Club de Leones 0 7,509 N Y N [Fig. 1; Ref. 1, pp. 

51593, 51595, 51603; 

6, p. 1] 

* The release wells (i.e., Ana Maria and Club de Leones) show an observed release. Therefore, the distance from 

the source is technically “0”; however, the distance from each release well (i.e., site reference point) to the center of 

the area of observed ground water contamination is 0.49 mile [Fig. 1; Ref. 1, pp. 51593, 51595; 6, p. 1]. 

** Several benchmarks can be considered for the ground water pathway, including Maximum Contaminant Level Goal 

(MCLGs), Maximum Contaminant Levels (MCLs), Cancer Risk Screen Concentration (CRSC), and Reference Dose 

Screen Concentration (RfD), to evaluate the level of contamination associated with contamination observed in the Ana 

Maria and Club de Leones wells [Ref. 1, p. 51593]. If the concentration of any applicable hazardous substance from any 

sample equals or exceeds its lowest applicable benchmark concentration, the sampling location is considered to be 

subject to Level I concentrations [Ref. 1, p. 51593]. Applicable benchmarks for the contaminants detected in the 

observed release, presented here in μg/L for consistency with reported data, are as follows: 

30 
Substance MCL/MCLG RfD CRSC Reference(s) 

PCE 5 360 1.6 2, p. 31 

TCE 5 11 0.21 2, p. 57 

cis-1,2-DCE 70 360 --- 2, p. 25 

1,1-DCE 7 1800 --- 2, p. 25 

See the next page for Level I concentrations detected in each well. 

GW-Targets 

31 
 

GW-Level I Concentrations 

Level I Concentrations 

Well Sample Substance Conc. (μg/L) Benchmark (μg/L) Reference(s) 

Ana Maria	 CR-GW04 PCE 1.9 1.6 (CRSC) 2, p. 31; 7, p. 5; 8, p. 52 

CR-GW04 TCE 0.63 0.21 (CRSC) 2, p. 57; 7, p. 5; 8, p. 52 

CR-GW14 PCE 1.9 1.6 (CRSC) 2, p. 31; 7, p. 5; 8, p. 70 

CR-GW14 TCE 0.62 0.21 (CRSC) 2, p. 57; 7, p. 5; 8, p. 70 

32 
GW-Nearest Well/Population 

3.3.1 Nearest Well 

As identified in Section 3.3 of this document, the drinking water well Ana Maria is subject to Level I concentrations. 

Therefore, a nearest well factor value of 50 is assigned [Ref. 1, pp. 51593, 51602-51603]. Also identified in Section 3.3 

of this document, the drinking water well Club de Leones is subject to Level II concentrations; the nearest well factor 

value for that well is 45 [Ref. 1, pp. 51602-51603]. 

================================================================================== 

Nearest Well Factor Value: 50 

3.3.2 Population 

3.3.2.2 Level I Concentrations 

As identified in Section 3.3 of this document, the drinking water well Ana Maria is considered Level I. The 

population assigned to each well is also explained in Section 3.3. 

Level I Well Population Reference(s) 

Ana Maria 1,856 [Ref. 6, p. 1] 

================================================================================== 

Population Served by Level I Wells: 1,856 Level I Concentrations Factor Value: 18,560 

3.3.2.3 Level II Concentrations 

As identified in Section 3.3 of this document, the drinking water well, Club de Leones is considered Level II. The 

population assigned to each well is also explained in Section 3.3. 

Level II Well Population Reference(s)
 

Club de Leones 7,509 [Ref. 6, p. 1] 

================================================================================== 

Population Served by Level II Wells: 7,509 Level II Concentrations Factor Value: 7,509 

3.3.2.4 Potential Contamination 

Due to the fact that the maximum score of 100.00 for the ground water pathway is achieved, potential contamination was 

not scored. 

================================================================================== 

Potential Contamination Factor Value: NS 

33 
GW- Resources/Wellhead Protection Area 

3.3.3 Resources 

Available information indicates that ground water extracted from the aquifer of concern within the 4-mile radius of the 

site is used as a resource (i.e., watering of commercial livestock). Therefore, a resources factor value of 5 is assigned 

[Ref. 1, p. 51604; 31, p. 19; 58, p. 1; 60, p. 1]. 

================================================================================== 

Resources Factor Value: 5 

3.3.4 Wellhead Protection Area 

The Wellhead Protection Program for Puerto Rico was developed in 1991 in accordance with Section 1428 of the Safe 

Drinking Water Act and subsequently approved by EPA [Ref. 10, pp. 1, 8-9; 11, p. 1]. Wellhead protection areas are 

defined by a fixed radius of 1,500 feet around each public supply well that does not withdraw water from the North Coast 

artesian limestone aquifer [Ref. 10, pp. 36, 40; 59, p. 1]. The wells associated with the Cabo Rojo Ground Water 

Contamination site (i.e., Ana Maria and Club de Leones) are located in the southwest region of Puerto Rico, outside of 

the North Coast artesian limestone aquifer, so the 1,500-foot fixed radius is applicable for the public supply wells within 

the target distance limit of the site [Ref. 10, pp. 8, 40; 59, p. 1]. Based on this information, observed ground water 

contamination associated with the site lies within a designated wellhead protection area (i.e., at the contaminated public 

supply wells), and a wellhead protection area factor value of 20 is assigned [Ref. 1, p. 51604]. 

================================================================================== 

Wellhead Protection Area Factor Value: 20 

34 
ATTACHMENT A 

WELL-SPECIFIC SCORESHEETS 

The Cabo Rojo Ground Water Contamination site consists of a ground water plume with no identified source(s) of 

contamination. The reference points for the site are two active public supply wells (Ana Maria and Club de Leones), 

with an observed release of contamination. These well-specific scoresheets, on a line by line basis, refer to the relevant 

page in the HRS documentation record where the values were determined and show that even if the two public supply 

wells were evaluated independently, they each would qualify for listing. 

35 
 

 

 

 

 

 

 

GROUND WATER MIGRATION PATHWAY SCORESHEET 

ANA MARIA WELL 

GROUND WATER MIGRATION PATHWAY MAXIMUM VALUE HRS 

Factor Categories & Factors VALUE ASSIGNED DOCUMENTATION 

RECORD PAGE 

Likelihood of Release to an Aquifer 

Aquifer: Bedrock Aquifer 

1. Observed Release 550 550 pp. 13-14; 21-23 

2. Potential to Release 

2a. Containment 10 

2b. Net Precipitation 10 

2c. Depth to Aquifer 5 

2d. Travel Time 35 

2e. Potential to Release 500 

[lines 2a (2b+2c+2d)] 

3. Likelihood of Release 550 550 pp. 21-23 

Waste Characteristics 

4. Toxicity/Mobility * 10,000 p. 28 

5. Hazardous Waste Quantity * 100 p. 29 

6. Waste Characteristics 100 32 p. 29 

Targets 

7. Nearest Well 50 50 p. 33 

8. Population 

8a. Level I Concentrations ** 18,560 p. 33 

8b. Level II Concentrations ** NS 

8c. Potential Contamination ** NS 

8d. Population (lines 8a+8b+8c) ** 18,560 

9. Resources 5 5 p. 34 

10. Wellhead Protection Area 20 20 p. 34 

11. Targets (lines 7+8d+9+10) ** 18,635 

12. Targets (including overlaying aquifers) ** 18,635 

13. Aquifer Score (lines 3x6x12 divided by 100 100 

82,500) 

GROUND WATER MIGRATION PATHWAY 100 100.00 

SCORE (Sgw) 

* Maximum value applies to waste characteristics category. 

** Maximum value not applicable. 

36 
 

 

 

 

 

 

 

GROUND WATER MIGRATION PATHWAY SCORESHEET 

CLUB DE LEONES WELL 

GROUND WATER MIGRATION PATHWAY MAXIMUM VALUE HRS 

Factor Categories & Factors VALUE ASSIGNED DOCUMENTATION 

RECORD PAGE 

Likelihood of Release to an Aquifer 

Aquifer: Bedrock Aquifer 

1. Observed Release 550 550 pp. 13-14; 21-23 

2. Potential to Release 

2a. Containment 10 

2b. Net Precipitation 10 

2c. Depth to Aquifer 5 

2d. Travel Time 35 

2e. Potential to Release 500 

[lines 2a (2b+2c+2d)] 

3. Likelihood of Release 550 550 pp. 21-23 

Waste Characteristics 

4. Toxicity/Mobility ** 100 p. 28 

5. Hazardous Waste Quantity * 100 p. 29 

6. Waste Characteristics 100 10 p. 29 

Targets 

7. Nearest Well 50 45 p. 33 

8. Population 

8a. Level I Concentrations ** NS p. 33 

8b. Level II Concentrations ** 7,509 

8c. Potential Contamination ** NS 

8d. Population (lines 8a+8b+8c) ** 7,509 

9. Resources 5 5 p. 34 

10. Wellhead Protection Area 20 20 p. 34 

11. Targets (lines 7+8d+9+10) ** 7,579 

12. Targets (including overlaying aquifers) ** 7,579 

13. Aquifer Score (lines 3x6x12 divided by 100 100 

82,500) 

GROUND WATER MIGRATION PATHWAY 100 100.00 

SCORE (Sgw) 

* Maximum value applies to waste characteristics category. 

** Maximum value not applicable. 

37