OSWER/OSRTI Washington, DC 20460



## N ATIONAL 

## P RIORITIES 

## L IST 

## (NPL)

***Final Site *** September 2012 

### WEST TROY CONTAMINAT ED AQUIFER Troy, Ohio

Miami County

 **Site Location :**  The West Troy Contamin ated Aquifer is located in the c ity of Troy. Troy operates two well fields located along a 1.25 mile

se gment of the Great Miami River. Troy’s West Well Field is currently comprised of five wells located on the east side of the Great Miami River on parklands bordering the river.

 **Site History:** Since 1986, volatile organic compounds (V OCs) have been detected in a drinking water production well which is part of the Troy’s West Well Field. The Ohio EPA conducted several investigations beginning in the early 1990s; however, a
definitive source for VOC contamination in the West Well Field h as not been identified.

 **Site Contamination/Contaminants:** Tetrachloroethene (PCE) has been detected in untreated water from Troy’s West Well Field public drinking water production well (PW) 12 at concentrations which exceed the federal drinking water m aximum contaminant level (MCL). Trichloroethene (TCE), cis -1,2- dichloroethene (DCE) and 1,1,1

- trichloroethane (TCA) have also been detected at lower concentrations. Low levels of DCE were also recently detected in PW

- 3W in Troy’s West Well Field

.

 **Potent ial Impacts on Surrounding Community/Environment**  **:**
The c ity of Troy obtains drinking water from two municipal well fields. There are five water wells in the East Well Field
and five water wells in the West Well Field. VOC contamination in the East Well Fiel d is being addressed under the East Troy Contaminated Aquifer National Priorities List (NPL) site. A separate ground water plume is moving toward Troy’s West Well Field. The municipal system supplies water to approximately 35,547 people.

 **Response Activi ties (to date):**  The EPA and the Ohio EPA have conducted assessment work for the ground water plume and source areas but have not identified the source of VOC contamination. Further investigation is needed to identify the source of VOC contamination and define the precise extent of the ground water plume.

 **Need for NPL Listing:** Applicable federal and state cleanup programs were evaluated to determine the prog ram to clean up this site. The s tate of Ohio referred the site to the EPA because a long

- term comp rehensive solution is needed to protect the c ity of Troy’s municipal wells. The Superfund NPL program provides the best approach to investigate and address all of the contamination sources and associated plumes at this site to protect human health and the environment. The EPA received a letter of support for placing this site on the NPL from the state governor on September 15, 2011.

[The description of the site (release) is based on information available at the time the site was evaluated with the HRS. The description may change as additional information is gathered on the sources and extent of contamination.]

For more information about the hazardous substances identified in this narrative summary, including general information regarding the effects of exposure to these substances on human health, please see the Agency for Toxic Substances and Disease Registry (ATSDR) ToxFAQs. ATSDR ToxFAQs ca n be found on the Internet

at http://www.atsdr.cdc.gov/toxfaqs/index.asp or by telephone at 1

- 888

- 42

- ATSDR or 1

- 888

- 422

- 8737.