Toxic solvent from dry-cleaners found in Memphis Sand aquifer
Source: http://www.commercialappeal.com, November 12, 2017
By: Tom Charlier
Investigators at a Memphis hazardous waste site discovered “elevated levels” of a toxic dry-cleaning solvent in the aquifer supplying the city with drinking water, a U.S. Environmental Protection Agency spokesman said.
The chemical – tetrachloroethylene, also known as perchloroethylene, or simply “perc” – was found 150 feet below ground in the Memphis Sand aquifer at the former Custom Cleaners site at 3517 Southern, near the University of Memphis campus, agency spokesman Jason McDonald said in an email.
A strata of saturated sand and gravel that’s 500 feet thick in many places, the Memphis Sand is an aquifer supplying Memphis and other local municipalities and industries with water renowned for its purity.
No sign of perc in drinking water
The former dry-cleaners property lies less than a mile from the Sheahan Pumping Station, one of the facilities where the Memphis Light, Gas and Water Division draws water from the aquifer. MLGW has not done any testing for perc since the latest findings by EPA, utility spokesman Richard Thompson said Friday, but her earlier monitoring turned up no trace of the chemical in Sheahan wells.
Perc is linked to liver, kidney and neurological problems and is believed to cause cancer. The chemical’s potential threat to drinking water led EPA earlier this year to add the dry-cleaners property to the national priority list of hazardous waste sites in need of cleanup under the federal Superfund program.
Many dry-cleaning businesses that operated before the advent of environmental regulations have been plagued with perc contamination. The tract at 3517 Southern had housed a laundry or dry-cleaning businesses for about 50 years until the mid-1990s.
After Custom Cleaners closed, an art-supplies business moved into the building. The woman who operated the store suffered health problems she blamed on breathing perc fumes oozing from soil contaminated by the dry-cleaners.
The structure has since been torn down, and in an initial cleanup operation last year, EPA removed the most heavily contaminated soil, excavating dirt to depths of up to 17 feet.
Discovery came in recent sampling
The discovery of perc in the Memphis Sand came in a further round of sampling. Having already found the chemical in soil and shallower groundwater at the property, an EPA contractor in August and September drilled five additional monitoring wells – two of them on the property of a neighboring McDonald’s restaurant – to depths of about 150 feet.
When the results came in, the EPA spokesman said, “elevated levels of (perc) were indicated in two of the wells sampled at a depth of approximately 150 feet below land surface in the Memphis Sands Aquifer.” One of the tainted wells is located on the McDonald’s property, the other was a previously installed well on-site.
For decades, local officials believed the Memphis Sand was secure from surface contamination because of a dense layer of clay that lies above it. But more recent studies have identified probable gaps in the clay, including one in the area near the dry-cleaners site.
The perc discovery isn’t the first evidence of contamination in the aquifer. During the late-1980s, three wells in MLGW’s Allen well field turned up trace levels of industrial organic compounds, although no customers received water that violated health standards. A similar discovery occurred in 2009, when three other wells in the Allen field were shut down after water was found to contain minute amounts of cancer-causing benzene.
In addition to the aquifer contamination beneath the property on Southern, the latest sampling detected elevated levels of the chemical in soil about 25-35 feet deep. However, EPA’s analysis of vapors seeping from the soil showed that the levels of perc were too low to pose a human health threat.
EPA and the Tennessee Department of Environment and Conservation continue to evaluate all the soil and groundwater data, McDonald said in the email.
“The data will be used to conduct a baseline human health risk assessment over the next few months, as well as determine the need to collect additional data,” he said
The analyses and risk assessment will be used to develop a cleanup strategy. Once a preferred alternative is selected, EPA will convene a public meeting to discuss its plans.
Responsible parties sought
While the contamination probe continues, EPA also is investigating potentially responsible parties – typically property owners or business operators – who could be found liable for some or all of the cleanup costs.
The property is part of a tract owned by Minor D. Madison Jr., Elizabeth L. Price and Anthony L. Logan Jr., according to Shelby County records. It has had a variety of operators over the years.
In 1985, Custom Cleaners Inc. filed incorporation papers with the Tennessee Secretary of State’s office. The registered agent was Mark Lovell, the fair-operator who earlier this year resigned his newly won seat in the State House of Representatives amid allegations of sexual improprieties.