There is an effort to allow companies to bring soils from out of state contaminated with lead, polychlorinated biphenyls (PCBs), asbestos and other toxic chemicals, treat them with an untested and unproven technology, and then use the treated contaminated soil as fill for constructing roads and parking lots throughout Maine.

The Maine Legislature’s Environment and Natural Resources Committee is considering rules to do this, and we strongly urge legislators to reject these rules.

The treatment technology, called “asphalt emulsion,” entails spraying liquid asphalt on contaminated soil and allowing it to dry. The treated soil could then be used under roads, parking lots and buildings, and in other construction projects.

There are many unanswered questions. What happens when road surfaces crack and water leaks through these contaminated soils underneath the road surface? What happens when workers tear up a road over these soils for resurfacing? Will the contaminants spread in the wind? Will tearing up the road surface let lead or PCBs leak into groundwater or nearby rivers and streams?

Maine’s Department of Environmental Protection has allowed the use of asphalt emulsion in the past, but only for soils contaminated with petroleum — not soils with significant amounts of other dangerous chemicals. Now, companies in Maine want to bring in contaminated soils from out-of-state urban or formerly industrial areas, and these soils may contain compounds other than petroleum, such as lead, PCBs and asbestos.

I have reviewed hundreds of documents from the department’s technical staff obtained through a Freedom of Access Act request. These documents clearly show that career staff have grave concerns about whether this technology can actually work in the long term to contain toxic contaminants such as lead, PCBs or asbestos.

One staff person described the situation in an internal email I reviewed: “[W]e just do not have answers. Not for projects in Maine, or projects in other states.”

According to this career staff person, it appears that no other state allows soils found at urban or industrial sites and then treated with this unproven technology to be used widely in construction.

Another career staffer stated in an internal email that the complete lack of studies showing whether asphalt emulsion works successfully as a treatment for a broad range of toxic chemicals gave him “heartburn.”

He stated that asphalt emulsion companies had “inadequate testing requirements” to know what is actually in the soils they take in. He had “questions about whether facility operators are able to understand the data they receive.” He also worried about “the impressive amount of money to be made by taking anything they can,” and called that “the icing on an already unpalatable cake.”

Asphalt emulsion is not a proven technology for treating the wide range of soil contamination for which some Maine companies want to use it. There is no evidence to support its use for hazardous contaminants such as lead, PCBs or asbestos.

These are contaminants that can be present in dangerous quantities in soils excavated from urban areas and former industrial sites. These are also contaminants that do not break down over time. They exist essentially forever. There is no evidence that asphalt emulsion can bind these contaminants permanently, keep Mainers safe and prevent toxic material from entering our air and water.

Materials like lead, PCBs and asbestos are too dangerous to spread throughout Maine under our roads, buildings and parking lots. The Legislature should not allow Maine companies to use dangerous contaminated soils as construction material all over our state. There is no proof that it is safe to do so, and Maine cannot afford to make the wrong decision. There is too much at stake.

Nick Bennett is a staff scientist at the Natural Resources Council of Maine.

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