WOBURN - An environmental clean-up firm recently unearthed asbestos containing materials and other chemical contaminates from an illegal solid waste dump on Winning Farm.

According to correspondence submitted to the Mass. Dept. of Environmental Protection (DEP) from Charter Environmental, soil samples excavated from 98 test pits dug at the Winning Farm waste site tested positive for asbestos and polycyclic aromatic hydrocarbons (PAHs).

"Based on our current evaluation of the analytical data for this material, the principal [contaminates of concern] are polycyclic aromatic hydrocarbons with concentration limits above the RCS-1 limits," Charter Environmental's director of redevelopment programs Edward Walsh wrote.

"With respect to asbestos containing material (ACM), trace amounts of asphalt roofing shingles that tested positive for non-friable ACM were found approximately 3 to 4 feet below surface grade in four of the ninety eight test pits," the correspondence to DEP's Solid Waste Section Chief John Carrigan furthered.

Charter Environmental, a Wilmington-based firm, has been hired by Burlington developers Gary Ruping and Robert Murray to oversee the cleanup of the 5-acre dumping site, located in the heart of the Woburn portion of Winning Farm along Lexington Street.

The Burlington developers, who purchased the last portion of the 115-acre farm that once sprawled across Woburn, Winchester, and Lexington, agreed to remove the waste before breaking ground on a 147 unit townhouse development.

Non-profit Winning Farm, Inc., the former custodians of the site, sold the last portion of the property to Ruping and Murray in the winter of 2006 for $5 million.

According to Woburn Health Agent Jack Fralick, based upon his understanding of the test results, the clean-up firm will slate approximately 51,000 cubic yards of contaminated fill for off-site disposal.

Another 14,000 cubic yards of fill will be set aside, re-tested, and then backfilled into the 5-acre dumping site, a baseball diamond shaped area located near the center of the property.

Because the asbestos containing shingles were found in limited quantities — an estimated 300 square feet of such debris is expected to be on the site — Charter Environmental is asking DEP that it be allowed to sift through the areas of concern and remove the asphalt-based materials by hand.

"It is what it is," said Fralick, when asked if he was surprised by any of the test results. "There are relatively low levels [of contaminates], but they are above standards. So it can't stay there."

"Most of their findings are related to asphalt being discovered there. And now it has to go," the Health Agent added. "They city will have an on-site observer there to make sure all the elements of the corrective action plan are complied with."

The test pits

In July of 2002, nearly 12 years after the Board of Health designated the 5-acre parcel as a solid waste disposal site, the Mass. DEP approved a remediation plan from the Burlington developers.

Ruping and Murray, whose Villages at Winning Farm development has been snagged for a number of years by legal challenges, have long contended, along with Winning Farm, Inc. officials, that the waste is primarily limited to construction debris such as concrete, asphalt, and other building materials.

However, concerned neighbors and residents, who formed the grassroots activist group Neighbors Opposed to Polluted Environments (NOPE), charged that toxic fill, excavated from the MBTA's Red Line extension project to Alewife Station during the 1970s, had routinely been dumped at the site.

According to copies of the test results, available for public inspection at the Woburn Public Library and Board of Health office, much of the debris discovered at the illegal dump was limited to building materials.

While Charter had to dig between four to five feet before reaching native, untouched soil in most testing pits, two areas, located in the eastern portion of the site closest to Winchester and the northwestern area of the site near Lexington, were mixed with large amounts of solid waste.

In those two locations, the environmental firm had to dig pits as much as 15 feet deep before native soil was reached.

Concrete blocks, crushed brick, scrap metal and metal spoils, pipe and wire, rebar, cobbles, asphalt, and burnt wood timbers were among some of the materials unearthed during the initial soil surveys.

According to information from the Center for Disease Control's (CDC) Agency for Toxic Substances and Disease Registry, the PAH contamination is likely from the large amount of asphalt found in the ground.

The agency, which list PAHs as chemicals created by the incomplete burning of coal, oil, wood, garbage, or organic foods, also explains that the contaminates are often found in crude oil, coal, coal tar pitch, and roofing tar.

PAHs, which are also found in burnt food, do occur naturally, such as during forest fires or volcanic eruptions, although the more dangerous chemicals, according to the government, are found in synthetic materials.

Although PAHs are known animal carcinogens, the government has not confirmed a definitive cancer link when humans are exposed to the substances, according to the CDC information.