Source: Wisconsin State Journal, September 2, 2012
Posted on: http://envfpn.advisen.com
Testing has turned up a probable culprit in the contamination of the Madison Water Utility’s Well No. 15 on the city’s East Side: cleaning solvents from a defunct dry cleaning shop on Lien Road.
Concerned about the well’s increasing levels of tetrachloroethylene, utility officials contracted with an engineering firm to conduct soil tests at suspect sites near the well in a search for a potential contaminant source. Tetrachloroethylene, also known as perchloroethylene (PCE), is a carcinogen.
Tom Heikkinen, the utility’s general manager, said the No. 1 candidate turned out to be a former dry cleaning shop at 3939 Lien Road. The location of the former Day One Formal Wear — which closed several years ago — is about 800 feet southeast of the well. Of several potential sources tested, he said, this was the closest site to the well and had the highest levels of PCE in soil test readings.
The discovery doesn’t come as a surprise, Heikkinen said, and the utility plans to install a treatment system to remove the PCE from the well water.
But, he added, it does help shed light on the challenge of detecting and dealing with contaminants in general, especially those from sources such as long-gone dry cleaning stores.
Dry cleaners a constant risk
It’s just the latest example of dry cleaning solvents turning up as a contaminant.
In May, chemical vapors from a dry cleaner were detected at Monona Grove High School at amounts that exceeded state action levels, though the vapors were not at levels high enough to pose a health hazard.
Those vapors were found to be coming from soil beneath a Klinke Cleaners next to the school at 5302 Monona Drive. The owner of the cleaners, Steve Klinke, said the company no longer uses PCE and the contaminant leached into the soil from past use.
The company is paying for tests and cleanup at the school.
Now, because of the growing number of such examples, the city of Madison and the state Department of Natural Resources are in the midst of a project to find and map historic locations of dry cleaning shops, going all the way back to World War II. It’s a search, said Brynn Bemis, a hydrogeologist with the city of Madison, that has required the skills of a detective and sleuthing through old city maps and even musty collections of yellow pages stored at the Wisconsin Historical Society.
The task is complicated by the sheer number of dry cleaning stores that have opened and closed around the city over the past decades.
“There are hundreds of them throughout the city,” Bemis said.
The locations of those long-gone stores are now obscured by strip malls and other commercial developments that have sprung up in the growing city over the years.
Even so, when a developer or a builder proposes a project, it is important that such sites be taken into account and soil be tested and cleaned up if a problem is found, Bemis said.
Bemis has spent hours poring over old city maps looking for clues, including enormous sets of so-called Sanborn maps, highly detailed fire insurance maps that show the location of buildings through the years.
The maps give detailed descriptions of the buildings for firefighting purposes, such as the number of stories and whether they were wood or brick.
Problem solvents no longer used
Also working on the project is Jim Walden, a hydrogeologist with the DNR. Among his tasks was going through old phone directories at the Wisconsin Historical Society, looking up the addresses of dry cleaners, most of which had long since disappeared.
Walden said PCE has become a problem because the solvent was unregulated for years and dry cleaners were not required to take precautions when using or disposing of the chemical.
He said the operation of older dry cleaning machines resulted in the solvent being spilled or draining onto floors and seeping, eventually, into the ground beneath the machines.
“So today, you look for where the machines were,” Walden said.
Walden said many cleaners today no longer use the solvents that have caused problems; newer dry cleaning machines are also safer, he added.
Heikkinen said the information gathered during the dry cleaner project will help the Madison Water Utility when it sites new wells and also when PCE shows up in tests, as it did in Well No. 15.
The well pumps drinking water for many neighborhoods east of East Washington Avenue, from Interstate 90 to the Yahara River.
The solvent was first detected in Well No. 15 in the early 1990s and, by 2010, levels were sometimes as high as 3.9 parts per million. The maximum safe contaminant level set by the federal Environmental Protection Agency for PCE is 5 ppm.
Heikkinen said more tests are being conducted to confirm the presence of PCE at the old dry cleaner site and to gather data that will be used to begin cleanup of the contaminant.
The city and the DNR also are trying to find the former Day One Formal Wear owners to recoup some of the costs that will accrue during cleanup.
In the meantime, a $2 million device called an air-stripper is being installed on Well No. 15 to remove PCE from drinking water. Such filtering could become more common, Heikkinen said, as contaminants from years past turn up to haunt us in the present.