LF plans to meet EPA phosphorous standards at lowest cost possible

City wants to pay down debt before waste water treatment plant needs expensive upgrade in 2022

By Terry LehrkeNews Editor

The city of Little Falls, like other cities, is required to get an Industrial National Pollutant Discharge Elimination System (NPDES) permit for its wastewater treatment facility. The city’s facility is located just north of the golf course.

The city’s five-year permit expired at the end of 2012 and to get a new five-year permit, is required to reduce its current phosphorus levels from 2.7 milligrams per liter (mp/l) to less than 1.7 mp/l.

In 2011, the city met the standard, but didn’t over a 4-year-average, Tom Roushar told the Little Falls City Council Monday.

Roushar is a senior project manager at WSB and Associates Inc., an engineering firm based in the Twin Cities.

He said the city’s plant is currently “doing a very nice job, but it isn’t quite getting phosphorus to as low as the new permit is going to require.”

The plant has the capacity to handle the organics now and for the near future, he said. A previous problem due to excess flow is being handled.

The new permit will be issued in August and will give the city until August 2019 to come into compliance, setting out a compliance schedule.

Roushar said the city is still paying down debt from a $4 million biosolids project at the plant in 2002 and another $2 million project to control odor in 2004, amounting to a significant amount of debt. Currently, the annual bond for those projects is $668,000 per year. By 2022, the last bond payment will be $475,000 and the debt will be retired.

Roushar suggested the city put into place a phosphorous reduction strategy that will do what is necessary for the permit, which will allow the city to retire the debt without taking on more.

By that time, he said, the city will have to spend millions to replace worn out components in the treatment plant. “It will be a significant expenditure in 2022 or thereabouts,” he said.

The treatment plant is “really close” to meeting the phosphorous reduction requirement now, said Roushar. “The one issue we have is a centrifuge which moves the sludge,” he said. “On the days that the centrifuge is operating, an awful lot of phosphorous is returned to the system.”

One thought, he said, is to chemically treat the side stream from the centrifuge. To put it into perspective, he said about 81,000 gallons of water comes off the sludge in the centrifuge. The plant treats about 7.7 million gallons a week.

“So you’ve got 1 percent of this really high phosphorous sludge — so the thought is to treat 1 percent of the flow, rather than the entire 7.7 million gallons,” said Roushar.

“That’s the first thing we would like to investigate,” he said. The plan may include chemical storage and chemical pumping to keep costs down at this time.

In 2022, the plant will be more than 35 years old. “Just like an old car, it’s time for an overhaul,” he said.

By then, the upgrade will include a new process to remove the phosphorous.

“Let’s not spend a lot of money on it (now),” said Roushar. “Let’s buy down the debt and by 2022 a lot of that equipment will be literally worn out and the entire plant gets overhauled. It will be a very large, costly project,” he said.

Greg McGillis, superintendent of both the Water and Wastewater Department, said the phosphorous comes from a number of products coming into the system through the solid waste.

The centrifuge spins the liquid from the solid waste that is collected when it comes into the plant.

The large drum that collects the solids, spins at 3,200 revolutions per minute. It separates the liquid from the solids. “It’s spinning really fast and that stuff is really pretty dry,” said McGillis. “The water is retreated and comes back.”

He said, “What happens is there’s a lot of phosphorous in the solids — phosphorous comes from soaps, digested food, industrial waste … there’s even phosphoric acid in pop. It’s in all kinds of products, including pharmaceuticals.”

The NPDES permit is a permit the city gets from the EPA through the state.

“The centrifuge is only part of the problem,” McGillis said. “We need to take care of that within the plant, and then deal with the other phosphorous coming in daily.”

Two streams come from the community — solid waste goes into one tank and then liquid waste, which is treated differently, McGillis said.

“In our case, the solids have the higher phosphorus,” he said.

“Right now, we’re hoping by treating that 1 percent (solids) — we won’t have to add any other chemical to other 99 percent,” which also saves money, he said. “We’re investigating how to do that.”

The process needs to be approved by the EPA. “There are steps on how to get there,” said McGillis.

To get the next five-year permit, “We don’t want to spend any more money than we absolutely have to,” he said.

“This plant is doing everything it was designed to do in 1985,” McGillis said. “It’s doing very well, but the rules have changed.”

He said all the communities in the area of the river are going through the same thing.

“The plant was designed for 20 years,” said McGillis. “But every five years, they want you to do something different and it just doesn’t work that way.

“Anytime you make a change, it’s a million bucks and that’s probably just capital costs,” he said.

Little Falls City Council Briefs

Other business conducted by the Little Falls City Council Monday, included:

• Approved in its consent agenda a name change for Iron Hills South Gun and Pawn at 118 N.E. First St., to Like-Nu Gun and Pawn for Chester Nelson, who purchased the business from his father;

• Approved on a 6-0 vote a change in the city’s ordinance regarding minors being allowed in bars until 9 p.m., with their parent or guardian to place the word “legal” before guardian in that sentence. Council President Don Klinker was absent and Council Member Greg Zylka abstained;

• Approved plans and specifications as recommended by the Airport Commission for repaving the north ramp at the Little Falls/Morrison County Airport and in so doing, approved advertising for bids;

• Approved hiring Kevin Schultz as a full-time equipment operator starting May 28, at a rate of $16.32 per hour, with benefits. Schultz  currently lives and works in Onamia. His hiring is contingent upon passing the physical exam and drug/alcohol testing. Public Works Director Jerry Lochner said 82 applications were received;

• Approved Mayor Cathy VanRisseghem’s appointment of Justin Bieganek to the Planning Commission. Bieganek was appointed to temporarily fill in during Randy Fossum’s leave of absence. However, Fossum will not be returning;

• Declared as surplus items a 2002 Pontiac Bonneville; a 2005 Chevrolet Impala; a 1999 Pontiac Bonneville; 11 folding chairs; yellow chair; HP printer/plotter; Xerox copier; Tally line printer; four black TV trays; a dishwasher; two small stands; 13 panels of draperies; 124 – 6-foot fence posts and 67 – 7-foot fence posts, to be sold for cash or disposed of. A wooden freezer on the list may be sold during a city auction;

• Accepted donations from the Canadian Cup Golf League – $315; Charles Lindbergh Historic Site – Lindbergh bust; Thomas and Teri Hoggarth – $90; Little Falls Lindbergh Lions – $7,000 and $2,025; Little Falls Lions – $500, $750 and $2,0900; Morrison County Public Health – an enclosed trailer to store bicycle safety training equipment and Clayton and Eileen Olson – $4.08, which was an overpayment. It was noted each time a donation is given, paperwork must be filled out and approved by the Council, no matter how small the amount;

• Approved new destination signs using fluted poles in a custom green color to be consistent with the color of the existing historic street lights. Froggy’s Signs and Graphix of Little Falls will create the signs and graphics at a cost of $4,575 and the cost for the poles is $5,996.01. The $10,541.01 cost will be split between the Tourism Fund and the Street Department Fund; and

• Heard a petition from Theresa Skorseth that the Council decide whether non-city residents should be able to travel to Le Bourget, France, and one from Robin Hensel, asking that the Council consider informing all members on all committees that discussion on land acquisition is forbidden. Both petitions were signed by Skorseth and Hensel.

The Council’s next meets Monday, May 20, at 7:30 p.m. at City Hall.

 

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