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A Few Facts about MTBE
Methyl Tertiary Butyl Ether, also known as MTBE, has been detected in a few monitoring wells on the Amoco former refinery site. MTBE is a chemical that is commonly added to gasoline to reduce engine knocks. It is also used in reformulated gasoline to reduce smog-forming air emissions.
MTBE is a concern because it has been showing up in groundwater throughout the country and it is not easy to cleanup. Although we do not know for sure, MTBE is thought to cause cancer in humans. In animal studies, rats and mice given MTBE have gotten sick or developed cancer.
The United States Environmental Protection Agency (EPA) recommends that, to protect children, drinking water levels of MTBE not be higher than 3 milligrams per liter (mg/L) or about 3000 parts per billion (ppb) for long-term exposure.1 MTBE has an unpleasant taste and odor, usually described as turpentine-like. People usually notice this unpleasant taste and odor at concentrations of 20 to 40 ppb. EPA recommends keeping MTBE contamination below 20 to 40 ppb to ensure that water does not have a bad taste.2
As of May, MTBE has been detected in only three public drinking water wells at two different sites in Missouri (City of Oran and Grandview Elementary School). MTBE has been found in 32 private drinking water wells in Missouri. The problem has been handled at these sites by installing new wells, connecting to a clean source of drinking water, installing a water treatment system such as charcoal filters, or using bottled water.2
The Missouri Department of Natural Resources and the EPA are watching for potential threats to Sugar Creek and Independence drinking water wells from MTBE or other contaminants that may migrate from the Amoco former refinery site. Water samples from monitoring wells installed between the Amoco former refinery site and drinking water wells for Sugar Creek and Independence will be tested four times per year for MTBE. Based on groundwater flow, any threat to the drinking water wells should be known at least 2 years before contaminants reach the well fields. This should provide time to stop the flow of contaminants before drinking water is affected.
References and Additional Information about MTBE
1. Agency for Toxic Substances and Disease Registry ToxFAQs Methyl tert-Butyl Ether (MTBE). September 1997. Internet address: http://www.atsdr.cdc.gov/tfacts91.html.
2. Missouri Department of Natural Resources MTBE Summary of Facts. May 2000. Contact MDNR Technical Assistance Program at 1-800-361-4827 for a copy of this fact sheet or visit the Missouri Department of Natural Resources' Web site at www.dnr.state.mo.us/mtbe for more information.
