OSWER/OSRTI Washington, DC 20460



## N ATIONAL 

## P RIORITIES 

## L IST 

## (NPL)

[The description of the site (release) is based on information available at the ti me 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 gener al 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 ToxF AQs can be found on
the Internet at http://www.atsdr.cdc.gov/toxfaq.html or by telephone at 1

- 888

- 42

- ATSDR or 1

- 888

- 422

- 8737. ***Proposed Site*** March 20 1 2 

### WEST TROY CONTAMINAT ED AQUIFER Troy, Ohio

Miami Count y

 **Site Location :**  The West Troy Contaminated Aquifer is located in the C ity of Troy. Troy operates two well fields located along a 1.25 mile seg ment of the Great Miami River. Troy’s West Well Field is comprised of four wells located on the east side of the Great Miami River on parklands bordering the river.

 **Site History:**
Since 1986, v olatile organic compounds (VOCs) have been detected in a pr oduction well which is part of the Troy’s

W est W ell F ield

. The Ohio EPA conducted several investigations beginning in the early 1990s ; however

, a definitive
source for VOC contamination in the West Well Field has not been identified.

 **Site Contaminati on/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 maximum contaminant level (MCL )

. Trichloroethe ne (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.

 **Potential Impacts on Surrounding Community/Environm ent**  **:**
The C ity of Troy obtains drinking water from two municipal well fields. There are five water wells in the East Well
Field and four water wells in the West Well Field. VOC contamination in the East Well Field is being addressed under the East Troy Cont aminated 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 2 8,000 people.

 **Response Activities (to date):**

The EPA and the Ohio EPA ha ve 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 best program to clean up this site. The

S tate of Ohio referred th e site to the EPA because a long

- term comprehensive solution is needed to protect the City 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 l etter of support f or placing this site on the NPL from the state governor on September 15, 2011

.