Coal contamination a wrench in the works
NAUGATUCK — The contractor that has been working to clean soil contaminants from Parcel C, the 2.2-acre, borough-owned tract at the corner of Maple and Water streets, has run into an enigmatic problem.
Manafort Bros. has been injecting an oxidizing chemical to neutralize the soil, which is contaminated with lead, petroleum and organic compounds left over from a Uniroyal factory that once occupied the site—that is, until last week, when it ran into semi-volatile coal and coal ash, which the oxidant cannot neutralize.
The deposits contain only microscopic pieces mixed with the soil, but are volatile enough to pose a threat. Ground testing has shown contamination slightly above the maximum levels allowed by law. Coal is a very hard solid, which is why the oxidizing chemical, which needs to not only penetrate the outer surface, but the core as well, cannot break through.
Mayor Robert Mezzo held an internal meeting at Town Hall Wednesday to discuss the unforeseen discovery. On hand were representatives of GeoDesign Environmental Engineers, the borough’s environmental consultant, Manafort Bros., the Naugatuck Public Works Department, the Naugatuck Economic Development Corp., and Conroy Development Co., a partner in the borough’s $710 million Renaissance Place project.
In the meeting, the representatives discussed the possibility of leaving the chemical substance in the ground and erecting a parking garage on the contaminated area, instead of adjusting to a more costly plan of attack.
“If we can put some of the substance that’s not responding to the treatment underneath the footprint of where that parking structure would go, that would allow us to remain in budget,” Mezzo said in a phone interview Wednesday.
If tests, which will be administered next week, come back saying the chemical is in certain areas of the property but not in others, which GeoDesign Environmental Engineer Allan Kovalik believes is the case, officials hope to encapsulate the chemical under the parking garage and follow thorough with plans to build a medical facility on the neutralized area.
St. Mary’s Hospital has agreed to build a state-of-the-art medical center on Parcel C, which some believe will be a catalyst for the long-forestalled Renaissance Place venture.
Leaving the chemical in the ground would prohibit any residential use directly on top of the contaminated area. A parking garage though, would not fall under into that category, and thus would be permissible.
“Our goal is to clean the entire site to residential standards, which is the highest form of remediation,” Mezzo said. “But if we’re not able to do that, then we would then have to look at where we can locate certain structures on the property.”
This approach is quite common in similar situations and is the prescribed arrangement for remediation, according to Kovalik.
“The goal was to do the soil treatment so that the property had unrestricted use,” Kovalik said. “Now what we may be forced into, which is an acceptable remedy but just a different path, is putting contaminated soil underneath the parking garage to make it inaccessible.”
This proposed technique, which would need to clear the state Department of Environmental Protection and federal Environmental Protection Agency, is to deposit two inches of clean fill on top of the contaminated area and lay the foundation of the parking garage on top of it.
Whether the project stays in line with a $1.4 million budget depends on how much coal and coal ash is in the ground, and what method is used to take it out.
“We’re hopeful right now that there isn’t going to be any increase,” Stewart said of the project’s budget. “It’s just finding out when the next step is and how it’s going to be remediated.”
The next step should come sometime in July. Workers will collect soil for additional treatment next week and ship the samples to a laboratory. Technicians will then apply chemicals and let the samples sit for a five-day “cure period.” At that point, they will take readings and report their findings
If there is a larger amount of coal and coal ash than expected, the contractor may need to take the substance out of the ground and transport it to a deposit site.
“We need to determine if it is likely that the rest of the site is similar,” Mezzo said. “If not, then we’ll clean as much as we can with the oxidizing method. But the material that will not respond, primarily the areas with the coal and coal ash, will need to be put somewhere.”
Collecting and transporting the substance would raise the price of the project substantially, but Mezzo insists it would not put a halt to the plans.
“We have a budget; we have to live within it,” he said. “But we’re going to determine what’s necessary to allow this site to be used.
Work will carry on while the tests are being completed, and workers will continue to remove other contaminants and debris such as rubber, pipes, old foundation, various metals and wood frames.
“I know it’s all good and well, but the best use for this spot is hardly a duck race staged once a year,” Mezzo said. “At the end of the day, we need to get this property cleaned.”