Environment and Natural Resources
For Immediate Release: Tuesday, July 30, 2002
For More Information: Tim Tollefsrud, 773-3153

DENR Provides Monitoring Data from CoEv Dumping

PIERRE – Today, the state Department of Environment and Natural Resources (DENR) is providing the monitoring data related to the CoEv dumping of water containing methyl ethyl ketone (MEK) that shows the MEK was confined to CoEv’s property. "All follow-up sampling showed negative results, and DENR is confident the MEK never left the site," said DENR Secretary Steve Pirner. "However, if people are concerned about their private wells, we invite them to call us, and DENR staff will sample your well for free. DENR will ask CoEv to reimburse the state for the sampling costs."

MEK, also known as 2-Butanone, is a manufactured chemical but also is present in the environment from natural sources. It is a colorless liquid with a sharp, sweet odor. MEK is used in paints and other coatings because it will evaporate quickly. It is also used in glues and as a cleaning agent. According to the Agency for Toxic Substance and Disease Registry, once released to the environment, one half of the MEK will break down when exposed to sunlight in 24 hours or less. It also dissolves in water and is broken down more slowly to a simpler chemical form in about two weeks.

In the summer of 2000, CoEv hired Earth Tech, an environmental consultant, from Minneapolis, to conduct a site assessment of the CoEv property in Watertown. It was Earth Tech’s responsibility to determine what impacts were caused as a result of CoEv employees dumping wastewater on the ground outside its building. DENR staff reviewed all work performed by Earth Tech, and provided regulatory oversite. The wastewater, which contained MEK, came from the printing process that puts an identifying mark on electrical transformers built at the plant that are used in electronic devices such as computers, telephones, etc.

On July 31, 2000, CoEv’s consultant Earth Tech drilled four soil borings near where the MEK was dumped on the ground and took ground water and soil samples from the borings. The water samples were tested for 71 different volatile organic compounds. MEK was the only volatile organic compound found in the ground water samples above laboratory detection levels, and was only found in two of the borings. The amount of MEK in the two ground water samples was 480,000 and 37 parts per billion. MEK was also detected in two soil samples about four feet below ground surface. The concentrations found in the two soil samples were eight and 24 parts per billion. Acetone, the only other volatile organic compound found during testing, was found in one soil sample at 46 parts per billion. 

After learning the results of the first water samples, the environmental consultant returned to CoEv on August 24, 2000, and drilled eight more borings in the area where MEK was detected in the ground water. Earth Tech collected water samples from five borings that contained water and soil samples from all eight borings. The water and soil samples were again tested for 71 volatile organic compounds. Volatile organic compounds, to include MEK, were not found in any of the water or soil samples in levels above laboratory detection methods.

After reviewing Earth Tech’s reports, DENR instructed CoEv to drill additional borings as a safeguard to determine if the MEK had migrated farther away from the dumping site and to install four monitoring wells at the site and begin sampling the wells on a quarterly basis. Earth Tech returned to the site in late January and early February 2001 and drilled 10 more soil borings and installed four ground water monitoring wells. Soil samples were taken from all 10 soil borings, which were all below laboratory detection levels for all 71 volatile organic compounds to include MEK. Ground water samples were taken on February 26, 2001, from the four wells, and all results were below laboratory detection levels for all 71 volatile organic compounds to include MEK. Earth Tech returned on May 1, 2001, and took samples again from the four monitoring wells. Again, the sample results for all 71 volatile organic compounds were below laboratory detection levels. 

Even though there was no evidence that MEK had migrated off CoEv’s property, DENR instructed CoEv to sample nearby private wells to make sure they did not contain any MEK. On September 6, 2001, Earth Tech employees with oversight from a DENR employee, took water samples from the drinking water taps at CSS Farms and Towle residence and an outside spigot at the Bohn residence. The water was sampled for MEK and four other chemical compounds that were expected to be created by the chemical breakdown of MEK. The monitoring wells at CoEv property were also sampled. The sample results for all five MEK related parameters were below laboratory detection levels. 

On December 4, 2001, Earth Tech again sampled the four monitoring wells at CoEv. The sample results for the same five MEK related parameters were again below laboratory detection levels. 

In summary, while MEK was originally found in two soil borings drilled on July 31, 2000, subsequent soil samples taken in the immediate vicinity of those two borings contained no detectable levels of MEK. Also, to date, MEK has only been detected in water taken from two soil borings that were drilled in July 2000. Since then, all subsequent water samples taken from the additional soil borings and monitoring wells installed at the site have been non-detect for MEK. Water samples taken from three private wells were also below laboratory detection methods for MEK and other chemical compounds that may be created by the chemical breakdown of MEK. 

While the data collected thus far has shown that MEK has not been found anywhere other than the immediate vicinity of where the dumping occurred and original samples taken, DENR wants to ensure residents in the area that the water from their private wells is safe to drink. If anyone has a private well near CoEv that you would like sampled for MEK, contact Jay Cofer, with the DENR regional office in Watertown, at (605)882-5111.

WATER SAMPLING RESULTS AT CoEv 

All results shown in parts per billion.

July 31, 2000 *

* Analysis conducted by En-Chem, Green Bay, Wisconsin
** Analysis conducted by Legend Technical Services from Minneapolis, Minnesota.

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