The Environmental Protection Agency and the state Department of Environmental Protection plan to study a 40-acre section on the grounds of the Altoona Water Authority’s Westerly Sewer Treatment Plant with the ultimate aim of removing legacy PCB-contaminated soil there, an action that would set to rest a longstanding authority problem.

The cost of that removal has been estimated to be in the “tens of millions of dollars,” according to Jim Balliet of the authority’s consulting engineering firm, Gwin Dobson & Foreman.

The DEP has moved to deal with the Westerly issue after having received $100 million in a settlement with Monsanto, Solutia Inc. and Pharmacia LLC in connection with polychlorinated biphenyl contamination in state waterways, according to online sources authority Sewer Operations Director Brad Kelly.

The ground at Westerly was the site of a lagoon that functioned as the original sewage treatment method used by the city, according to Balliet, speaking at an authority meeting this week.

The lagoon contained tiles that allowed the water to percolate through the ground, while solids hardened on top, according to Balliet and Kelly.

That method of disposal was “terminated” in the 1950s, when the city built its first sewer plant, according to Balliet.

The lagoons, however, were repurposed as a repository for solids generated by the plant, which were pumped to the lagoon for “dewatering,” Balliet said.

The problem resulted from a period during the 1970s when oil that contained the PCBs was dumped into the lagoon, Balliet said.

Polychlorinated biphenyls are “high-stability,” non-flammable, insulating substances that were used in transformers, caulking, paint and plastics — and that are also “toxic, persistent environmental pollutants,” according to an online source.

They were produced from 1929 until they were banned in the U.S. in 1979, according to the source.

Starting in the 1990s, there were studies of the Westerly lagoon to determine the concentration of the PCBs and the extent of their presence there, Balliet said.

There were periods of high attention from the EPA and DEP and periods of no attention, Balliet said.

The studies have shown that the PCBs have not migrated off-site, Balliet said.

Soil tends to hold it in place, he said.

Vegetation also helps with the process by their “uptake” of the problematic chemicals, according to another authority official.

Moreover, the PCBs degrade, although they do it slowly, Balliet said.

“Time is on our side,” he said. “The longer it sits, the better.”

There had been a proposal to cap the site, but now the focus seems to be removal, according to Balliet.

Within the next couple of weeks, workers under the EPA will be drilling test wells, according to Kelly.

The prospective cleanup would be at no cost to the authority, the officials said.

The authority couldn’t afford to do it, Balliet said.

Health issues associated with exposure to PCBs include “acne-like skin conditions in adults and neurobehavioral and immunological changes in children,” according to a publication of the Agency for Toxic Substances and Disease Registry and the Centers for Disease Control and Prevention. PCBs have been known to cause cancer in animals, according to the publication.

Mirror Staff Writer William Kibler is at 814-949-7038.