Stage of Clean-up: Construction Completed

Conditions at listing (September 1983): The well field supplying 28,500 residents of Vega Alta, Puerto Rico, consists of five wells. All are contaminated with chlorinated solvents. One, the Ponderosa well, was closed in January l983 when a survey of public water wells made by the U.S. Geological Survey (USGS) detected high levels of TRICHLOROETHYLENE. The Puerto Rico Aqueduct and Sewer Authority is trucking and/or piping in drinking water to the residents. The source of the contamination has not been identified. Status (June 1984): Through an Interagency Agreement with EPA, USGS plans to undertake a preliminary hydrogeological assessment of the site. The study will be integrated into a remedial investigation/feasibility study EPA is planning to identify the source(s) of contamination and alternatives for remedial action.

Sources of Contamination:

• Discharge to sewer/surface water
• Inadvertent spill
• Manufacturing process
• Underground injection

Groundwater, and soils are contaminated with various VOCS. People who accidentally ingest or come into direct contact with the contaminants in the affected wells may be at risk.

Contaminants Detected
	Ground Water	Surface Water	Air	Soil	Other
1,2-TRANS-DICHLOROETHYLENE					X
CHLOROFORM					X
DIELDRIN	X
TETRACHLOROETHYLENE	X
TOLUENE					X
TRICHLOROETHYLENE	X

Groundwater and Drinking Water
Were drinking water wells shut down due to contamination?	Yes
Population served by the wells now shut down:	1,001 - 5,000
Are drinking water wells potentially threatened?	Yes
Population served by the threatened wells:	1,001 - 5,000
Aquifer discharges into:	A drinking water aquifer
	Surface water
Population served by water wells in the aquifer:	10,001 - 100,000

List ground water uses.

EPA Hazard Ranking System scores for VEGA ALTA PUBLIC SUPPLY WELLS:

Less Hazard

National Average

More Hazard

0%					50%					100%

Overall site:

Ground water migration:

Rank Superfund sites in the U.S., PUERTO RICO, or in VEGA ALTA County by EPA Hazard Ranking Scores.

*Note: EPA's Hazard Ranking System is designed to screen and prioritize sites for the Superfund program, based on limited data available at time of listing. These scores are not based on a comprehensive risk assessment of the site and do not reflect conditions after initiation of cleanup work.

Number of PRPs currently associated with this site:	5
Hazardous waste received from off-site generators/transporters?	No
Number of owners/operators which are also municipalities:	0

EPA Site Information

• NPL Fact Sheet
• Government Accounting Office (GAO) assessment
• Record of Decision (ROD) Abstracts
• NPL Site 5 Year Reviews
• Comprehensive Environmental Response, Compensation, and Liability Information System (CERCLIS) Hazardous Waste Site Information
• Superfund Hazardous Waste Site Advanced Query Form

Scorecard reports for VEGA ALTA County on:

• Potential Sources of Land Contamination