OSWER/OSRTI

Washington, DC 20460

N P L (NPL) ATIONAL RIORITIES IST 

***Proposed Site*** October 2010 

WEST COUNTY ROAD 112 GROUND 

WATER 

Midland, Texas 

Midland County 

 Site Location:

The West County Road 112 Ground Water site is a ground water plume of chromium/hexavalent chromium located in a 

rural area of Midland County, Texas immediately to the southwest of the city limits of Midland. The center of the site is 

designated as 2601 West County Road 112, Midland, Texas. The site plume currently extends 1 1⁄4 miles from the center of 

the site and is situated under approximately 260 acres. 

 Site History:

The site was identified in April 2009 by a local resident who asked the Texas Commission on Environmental Quality 

(TCEQ) to test his private well due to yellow discoloration. Sampling of this well revealed the presence of 5,280 ppb of 

hexavalent chromium. To date, approximately 234 water wells have been sampled by the TCEQ and 46 water wells have 

concentrations of total chromium above the Maximum Contaminant Levels (MCLs) of 100 ppb. TCEQ has installed water 

filtration systems at homes where total chromium has been detected above the MCLs. 

 Site Contamination/Contaminants:

An Expanded Site Investigation was conducted in February 2010, and no sources were identified. The site is being 

evaluated as a ground water plume of chromium/hexavalent chromium with no identified source. Concentrations of 

chromium in the wells are as high as 5,280 ppb. 

 Potential Impacts on Surrounding Community/Environment: 

Forty-six residential wells have chromium contamination above MCLs, in some cases more than ten times the MCL. Until 

the source has been identified and controlled, the plume will continue to contaminate remaining private and public wells. 

The drinking water wells in the contaminated aquifer are the only source of water for these residents, who have been 

drinking the water as well as using it for other consumptive purposes. 

 Response Activities (to date):

The TCEQ is currently monitoring the ground water plume and to date have sampled 234 wells and installed treatment 

systems on wells that have been identified with hexavalent chromium concentrations exceeding MCL. TCEQ is providing 

the systems and quarterly monitoring at no costs to the residents. EPA Region 6 is currently evaluating the site for a 

possible Superfund removal action. 

 Need for NPL Listing:

The State of Texas referred the site to EPA for NPL listing and potential remedial activities. The potable water is in a 

relatively shallow aquifer (70-100 feet deep). Without identification and investigation of the source of ground water 

contamination and remediation of the contaminated ground water plume, the remaining public supply and private wells will 

be contaminated. Other federal and state cleanup programs were evaluated but are not viable at this time.

[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 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.