Small Town Ingenuity at Work
By Cornelia Cesari

Chelsea’s selectboard, wastewater treatment plant operator, and road foreman have collaborated to effect an innovative, cost-effective modification for the town.

When Nolan LaFrancis, Chelsea’s water treatment plant operator, thought about the drying bed building, it just didn’t make sense. "I know we’re the water treatment department, and they’re the road department… but it’s foolish for them to be out of room, and here’s this building," he said.

The building is a 46’ x 54’ shed consisting of a steel frame covered with fiberglass. The structure is part of the original plant, built in 1974 and expected to last 25 years. The 33-year-old fiberglass is, predictably, brittle and liberally freckled with holes. The building is desperately in need of repair if it is to be saved.

The original purpose of the building is to hold the "sludge beds." A 2,500 gallon charge of wastewater is flooded onto two beds, each 22’ x 32’. The liquid seeps down through the porous sand surface and drains back into the tanks for processing. The remaining sludge dries on the surface. It needs to be stirred, chopped and turned until it is truly dry; then it is scraped up, shoveled into grain bags, and disposed of. The sludge bed then needs to be scrubbed and pressure washed to open up the filtering system.

Back in 1974, the bags of raw solids could be taken to a "sanitary landfill" or even spread on fields. More recently, Jay’s Septic has taken it as a favor to the town, and added the waste to its own lagoons, where it is re-hydrated and properly processed.

This material is untreated, raw "biosolids," which have not yet been sanitized to control pathogens. In its dried form, dusty particles are stirred up into the air. In 1998, an environmental engineer from the Residuals Management Section of the Wastewater Management Division of the Agency of Natural Resources wrote a letter concerning Chelsea’s practice. It states, "While we can not tell you to terminate this activity, we are discouraging it." Further, the department reveals that it was not their intention to authorize this activity, and expresses concerns about town employees bagging the de-watered biosolids.

According to the National Institute for Occupational Safety and Health, "There are four major types of human disease-causing organisms (pathogens) that can be found in sewage: (1) bacteria, (2) viruses, (3) protozoa, and (4) helminths (parasitic worms). …Both Class A and Class B biosolids may also contain chemicals (including metals) and allergens." The NIOSH publication details health hazards to workers handling biosolids in the way the drying sheds are emptied and cleaned.

Use of the drying beds, LaFrancis calculates, saves the town about $800 a year, providing Jay’s Septic continues to dispose of the solids free of charge. Whether or not to continue the practice is a moot point, however; without roof repair, the drying sheds are currently unusable.

"It rains pretty hard in here!" laughs LaFrancis.

However, even in full use, the drying shed sits empty during the fall and winter months. On the sand and gravel beds are concrete wheel pads so that a truck can back in while cleaning. It occurred to LaFrancis that the town road crew, so pressed for space, could be making use of this building during the winter months. He checked with the state, to be sure it would be legal to park equipment in the building; he also ensured that the drying beds can still be used in the summer months, if the town chooses to resume the practice after roof repair.

Chelsea’s road foreman, Rick Ackerman, is glad to have the space. He stores tires, the lime spreader, and tailgate sander in the shed and hopes to get the backhoe, Ford L8000 dump truck, and loader out of the elements as well.

"It’s not warm storage, where we could wash the salt off the equipment, but it’s good to get it all out of the snowbank," he said, adding that any shelter will help extend equipment life.

Throughout the process, the selectboard has acted to guide and supervise. It has raised questions and requested documentation, compared estimates for the necessary work, and designated funds from the appropriate sources. The $16,400 for work to the building, including a standing seam roof and new doors, will come from the sewer savings account, set up for just such expenses: upgrades and maintenance to the facilities.

The road budget will pay for the expense of cutting back the concrete so that larger trucks can access the space. This has been accomplished in such a way that the capacity of the drying beds is not compromised; the height of the walls will still hold a full charge. The actual wheel pads will be unchanged.

Selectboard chair Andy Pomerantz is pleased with the way things have turned out, and notes, "Nolan came up with a single solution for both a sewer and a highway problem. This plan saves the drying bed building and provides a shelter for the equipment as well."

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