No one ever claimed running a sewage treatment plant was glamorous.
Most people would go no further than saying it was an interesting job that probably had its lighter moments.
Professional life these days is about as interesting as it gets for Ralph Mishou, director of the Bangor Waste Water Treatment Plant.
He is in the midst of the construction of a $16 million secondary treatment plant, a concrete colossus rising on the banks of the Penobscot River off Main Street at the Hampden town line.
To be sure, though, the job has a humorous side. The one incident Mishou readily recalls happened early in his tenure.
“I’ve been here about 25 years and had a half dozen calls from people who flushed things down the toilet. At one time we had an old guy call to say he’d flushed his false teeth,” Mishou said Monday afternoon.
“And we actually found both the uppers and lowers. He was tickled pink,” Mishou said. An employee found the dentures on the top of the screening box, one of the first steps of treatment in which debris larger than 1 inch square is screened out of the sewage.
Lest anyone think working in a treatment plant has only non-monetary benefits, Mishou recalled the time a plant worker found a $5 bill on the screening box. A corner of the bill was ripped off.
Through the day workers kept an eye on the screening box.
“They found tens and twenties all identically torn. All told they found $520 that day,” Mishou said, “which they kept.”
Earlier in the afternoon a business demeanor hid Mishou’s jocularity as he conducted a tour of the construction site for several members of the Bangor City Council.
The existing plant is 25 years old and working well but the treated water emerging from it doesn’t meet stiffer federal standards established since the plant was built. Last year an average of 8 million gallons a day was pumped into the plant. The sewage enters the system running through the screening box and is pumped into settling basins.
As Brad Moore, an instrument mechanic at the plant, explained to the councilors, floatables — grease, paper, plastic and cloth — are mechanically raked off the surface. Sludge — organic matter — settles to the bottom and is collected. The surface scum is stored and a couple of times a year trucked to a landfill. The sludge is processed to remove water. It then is mixed with wood chips or, after the holidays, with chipped Christmas trees and composted.
After that primary treatment, the waste water is treated with chlorine and discharged into the Penobscot River.
The discharge no longer meets the standards set by the Environmental Protection Agency. Part of the massive overhaul of the sewage systems required by the EPA includes the secondary plant.
The new treatment plan is designed for a maximum daily flow of 30 million gallons, although at peak capacity it could handle a rate of 43 million gallons a day.
Instead of being treated with chlorine and pumped overboard after primary treatment, the waste water will be pumped to the secondary plant. The first stage of the process is an aereated biofilter, said Michael Willson of CH2M-Hill, the engineering firm that designed the plant. The huge tank will serve as home to a wide variety of micro-organisms. As the waste water trickles through the biofilter, the micro-organisms will consume organic matter.
After that it will be pumped into one of two 1.4 million gallon clarifiers that will separate more solids. The waste water then will be treated with chlorine to kill remaining bacteria and the chlorine will be neutralized before the water is discharged into the river.
After several years of negotiations with the EPA and design work, construction began a year ago. CH2M-Hill also is overseeing construction and Willson said that the project is 40 percent complete in terms of time and money. About 75 people are working on the construction of the plant.
Construction is expected to be complete in December 1992 and a shakedown period of two or three months is anticipated. Mishou looks forward to the day when he can get back to treating sewage and not be faced with the worries associated with any large construction project.
Comments
comments for this post are closed