OSWER/OSRTI

Washington, DC 20460

NATIONAL PRIORITIES LIST (NPL) 

***Proposed Site*** September 2014 

KOKOMO CONTAMINATED Kokomo, Indiana

GROUND WATER PLUME Howard County

 Site Location: 

The Kokomo Contaminated Ground Water Plume site is a contaminated ground water plume with no identified source 

located in the city of Kokomo, Howard County, Indiana. The ground water plume is approximately 294 acres and 

encompasses several municipal wells in the city. 

 Site History:

Site investigations in 2007 confirmed levels of vinyl chloride at levels exceeding the EPA maximum contaminant 

level (MCL) in raw water at four (4) municipal wells (pre-treatment). The Indiana Department of Environmental 

Management (IDEM) has identified fourteen handlers of chlorinated solvents in the area that could be contributing to 

the contaminated ground water plume. Despite several investigations in the area, the exact origin of the contaminants 

is unknown.

 Site Contamination/Contaminants:

The plume consists of chlorinated solvents, specifically, vinyl chloride. 

 Potential Impacts on Surrounding Community/Environment: 

Area residents are supplied by municipal water supply distribution systems and use municipal water as their drinking 

water source. The affected wellfield provides water to about to 55,000 residents in Kokomo. There are known 

contaminated residential wells which are believed to be used for non-potable purposes. 

 Response Activities (to date):

IDEM has identified fourteen facilities that handle chlorinated solvents and could be sources to the contamination 

plume. Some of these potential sources are currently being managed under other authorities but there is no cleanup 

approach focusing on the ground water plume. Water from several well fields in Kokomo are blended and treated prior 

to distribution. The water treatment system has been successful at removing the vinyl chloride from the finished 

drinking water, as there have been no detections in the finished water, but this is not a permanent solution. 

 Need for NPL Listing:

The state of Indiana referred the site to the EPA because the site requires a long term response and action. Listing will 

allow for a proper and timely investigation of the nature and extent of contamination. Other federal and state cleanup 

programs were evaluated but are not viable at this time. The city’s mayor has expressed support for listing, and the 

EPA received a letter of support from the state. 

[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. See 56 FR 5600, February 11, 1991, or subsequent 

FR notices.]

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/toxfaqs/index.asp or by telephone at 1-888-42-ATSDR or 1-888-422-8737.