Selbyville Town Council members unanimously agreed at their Feb. 7 meeting to assess Mountaire Corporation a fine of $3,000 for sewage violations in November. An administrative penalty of $1,000 was assessed for each of three incidents in which the company exceeded maximum levels for biochemical (or biological) oxygen demand (BOD).
BOD is a measure of water quality, determined by the amount of oxygen needed by bacteria and other microorganisms to oxidize the organic matter present in a water sample. (The BOD of drinking water should be less than 1. That of raw sewage may run to several hundred.)
Mountaire spokesmen present at the Feb. 7 meeting did not object to the fines. Prior to the discussion of sewage matters, they had presented to council members several elements of “intense programs” designed to “build a relationship with the town in regards to cleanliness.” Among the programs were new brushes for the company’s street sweeper, to assist it “to be a good neighbor.”
Mountaire representatives also spoke at length about the plant’s efforts at water conservation through technology. The technological changes are focused at reducing wastewater pumped into the town’s system via water recovery (recycling).
The resulting wastewater has more concentrated levels of contaminants but is reduced in volume. The company’s first efforts were begun in December and succeeded in reducing wastewater output by 150,000 gallons per day.
However, Mountaire representatives acknowledged some initial problems with the system that led to excessive BOD levels during its first week of operation. The problem has since been fixed, they said, emphasizing that the company’s goal is to be the top company in the nation in terms of their success in wastewater management.
“That’s good,” Mayor Clifton C. Murray said of the efforts by Mountaire. “It sounds like you’re on the right track.”
Mountaire’s current efforts will continue, with investigation ongoing for supplementary treatment systems that could be implemented as additional steps to their current treatment process. Representatives said those options had been narrowed from 25 to three, with criteria of minimizing noise, odors and physical footprint, as well as selecting a system with a proven history.
Currently, they said, the company is considering a “moving bed bio-film reactor” (MBBR) that combines elements of activated sludge systems with a bio-film. Representatives noted that the system is cold-weather tested, easy for the operator to use, fully automated, has a low retention time for water being treated and is adaptable to highs and lows in flow.
It also has a rapid recovery time of two to three hours from incidents of toxic shock, where a toxic contaminant might accidentally find its way into the system and might otherwise require days or weeks to recover, they said.
The MBBR would also allow the company to use less chlorine in treating wastewater, and the anaerobic bacteria used generate no methane. The end-product waste — a “bio-mass” — would be applied at its normal location with other bio-solids from the company’s Millsboro plant, in the amount of approximately one tanker load per week.
Mountaire representatives said the system is currently under serious consideration by the company, with work currently focusing on engineering layouts and developing fail-safes. The size of the system is a determining factor in the end purity of the resulting wastewater, they said. “You can get almost to where you can recycle the water back to the processing plant,” a representative said. However, the size of the system would, they said, be no higher than the existing FEB2 treatment system, at 25 feet.
If the MBBR system is selected, the engineering stage should be completed by the end of March.
“This is all positive news,” Murray commented.
Mountaire representatives also presented an informal proposal to council members for a shelter for its outside workers. The structure would have no sides but would have a roof to protect the employees from precipitation.
They noted that the fire marshal and county had granted a permit for the structure, with the town being the next entity from which the company would seek approval. Plans for the structure were to be delivered to the town on Tuesday, Feb. 8.