Public health officials are awaiting soil test results that will tell them whether the latest repairs to Madison-Kipp’s underground storm drain system have finally halted the flow of toxic PCBs from the plant site to a strip of public land along a busy East Side bike path.
Hazardous polychlorinated biphenyls were detected at two times to five times the legal limit for industrial land in two of 15 samples collected through June 30.
That was after the company removed 52 tons of contaminated soil and concrete and performed an initial round of storm-drain maintenance in response to testing that found the probable carcinogen in a city rain garden and traced them to the drain.
PCBs have been documented on the city land just north of the Madison-Kipp plant since at least 2012, but Public Health Madison and Dane County said it was unlikely members of the public have had enough contact with the chemicals for ill health effects.
“The recontamination of the rain garden with PCB is concerning and frustrating, but it does not change the current use of the property including the rain garden,” said department spokeswoman Sarah Mattes. Madison-Kipp “needs to find the source of the PCBs that continue to move into the rain garden and take the necessary action to stop that movement.”
The company has erected a temporary fence around the rain garden, and in July Madison-Kipp president and CEO Tony Koblinski told neighbors of the plant, which stands on Atwood Avenue in the densely populated Isthmus, that the company would eventually erect a permanent fence.
In an email, Koblinski also told them Madison-Kipp would make more drain repairs, remove more soil and do further testing for PCBs in the rain garden. However, Koblinski declined to say last week whether the company’s consultants had obtained more test results.
TRC, a consulting firm working for Madison-Kipp, said in a July 11 report filed with the state that it has concluded that PCBs in the rain garden were not being washed off the company’s parking lot by rain and they weren’t originating from the factory’s smoke stacks.
The toxins were likely in shallow soil on the plant site that was entering the storm drain system through cracks, manholes and other openings, the report says.
PCBs banned in the 1970s
The chemicals were used by the company in hydraulic fluids before they were banned in the 1970s.
When PCBs were detected in the rain garden in 2012, Madison-Kipp officials suggested that rain had carried them from the company’s parking lot, where workers had dumped oils and fluids decades earlier to keep dust down before it was paved.
The state Department of Natural Resources issued a notice of violation and a letter accusing the company of knowing about PCB contamination on the site since 2006 without informing the state or the public.
The violation was included among the allegations in a 2012 state Department of Justice lawsuit. The suit sought penalties for PCBs on the Madison-Kipp property and around it, as well as for PCE, another likely human carcinogen, that escaped the plant, got into ground water and sent hazardous vapors into nearby homes.
The company paid $7.2 million to settle neighbors’ PCE lawsuits, and Koblinski has said he expected the state action to be settled after the DNR closed its investigation of PCBs in the rain garden in July 2016 because it appeared the company had removed all contaminated soil.
But the city sampled soil in October and found more PCBs. Subsequent testing found high concentrations in drains that carry rain water from the company property.
High levels under factory
In negotiations with government regulators, Madison-Kipp is arguing that its parking lot and the plant have effectively capped the soil contamination by preventing rain water and snow melt from spreading it, said John Hausbeck, the health department’s environmental health services supervisor.
PCB concentrations of 50 parts per million or less don’t need to be cleaned up if they are capped by an impermeable surface, Hausbeck said.
“The parking lot is considered a cap, so the PCBs shouldn’t be moving out of there, unless of course you have a drain pipe carrying them out,” Hausbeck said.
Levels of up to 20,000 parts per million have been found under the plant floor. The contamination is as deep as 25 to 30 feet below a 3-foot-wide trench of cracked concrete that once ran down the center aisle of the plant.
In 2014, the company excavated to a depth of 3 to 4 feet in an 8-foot-wide, 168-foot-long rectangle around the trench, but it left most of the tainted soil in place.
The industrial limit was 0.74 parts per million until March, when the DNR increased it to 0.97 parts per million based on data from the U.S. Environmental Protection Agency.
The lower residential limit was increased slightly. The soil around Madison-Kipp will be cleaned up to meet the industrial limit that was in place when the contamination was discovered.
Very high concentrations of PCBs can cause health problems relatively quickly, but the lower levels found outside the plant are likely hazardous only after prolonged contact because the toxin accumulates in tissue, Hausbeck said.
PCB typically binds with soil and can be taken into the body through ingestion, inhalation of dust or vapors or skin contact. It presents greater risks in higher concentrations.
Madison-Kipp “needs to find the source of the PCBs ... (and) stop that movement.” Sarah Mattes, Public Health
Madison and Dane County