The City of Perham will pay a $70,000 penalty to the Minnesota Pollution Control Agency as a result of complaints about wastewater treatment pond odors.
The city must also start enforcing discharge agreements with local industries, charging surcharges to industrial facilities when they exceed their effluent limits.
Information released by the MPCA last week states that the agency received “numerous complaints” about odor coming from the treatment plant, beginning in April 2012. Some people claimed they could not have their windows open or hang clothes outside, and others said they were made sick by the smell.
As a result, the MPCA conducted an investigation and found that the air at the treatment plant, on “numerous instances,” exceeded the state standard for acceptable concentration levels of hydrogen sulfide. Air quality was also monitored at locations in town; those tests all came back clear.
The investigation also revealed that the city had, since 2009, failed to adequately regulate discharges to the treatment plant from four local industrial facilities: Barrel O’ Fun Snack Food, Kenny’s Candy, Tuffy’s Pet Foods and Perham Egg.
Barrel O’ Fun exceeded its limit for flow for 24 consecutive months during 2011-2012.
When asked why the city did not regulate industrial discharges, City Manager Kelcey Klemm said, “The only option we would have had to regulate, per say, would have been to restrict flow, and that’s kind of hard to do…because the industries would have had to shut down if their flows were restricted.”
According to the MPCA, discharges containing excessive organic material from all four industrial facilities contributed to depressed dissolved oxygen levels in the treatment ponds, which can lead to odor problems.
The MPCA found that the city failed to require the industrial facilities to pay surcharges for not complying with effluent limits.
Those surcharges went into effect in the final quarter of 2012, Klemm said, but were not prorated to include earlier instances of noncompliance.
The MPCA also found that, since 2009, discharges from three of the four industrial facilities had pH levels below 5.0, which can be corrosive to infrastructure.
In addition, the MPCA’s review of records and onsite inspections revealed, among other things, that the city did not:
-properly operate and maintain its pond systems to ensure effective performance;
-notify the MPCA of an industrial user (Industrial Finishing Services) that may be subject to pretreatment requirements;
-sample industrial discharges on cleanup days, when potentially larger amounts of pollutants might enter the treatment system;
-operate the facility in accordance with certain design specifications;
-keep proper records for, or adequately maintain and/or calibrate, various types of monitoring and pumping equipment.
“The city was kind of in a tough situation,” said Klemm.
Explaining that the newly completed expansion project at the treatment facility took more than a year longer to get up and running than originally expected, he added, “For every month or quarter or year that the expansion project didn’t occur, we were that much further behind.”
“We were in violation with the MPCA because of our inability to treat and hold that much flow and loading,” he said, “and on the flip side, we weren’t able to adjust the user agreements to reflect what the new ponds would handle.”
Now, “The city has completed the expansion and that’s really what needed to be done. And we’re working with our industries to correct the problem,” said Klemm.
According to the MPCA, recent upgrades to the treatment facility, such as additional aeration within the primary ponds and an additional secondary treatment pond cell, resulted in increased dissolved oxygen levels and far fewer odor complaints throughout the summer of 2013.
Furthermore, the largest organic loading facility is in the process of installing additional pretreatment equipment, and has taken interim measures to reduce organic loading, which has also helped ensure adequate wastewater treatment.
The city has also developed an action plan for responding to future odor complaints. The plan includes monitoring for hydrogen sulfide at the property boundary and nearest downwind residence when the city receives a complaint.
The $70,000 penalty will come out of the city’s wastewater fund, which is supported by wastewater fees, according to Klemm.
When calculating penalties, the MPCA takes into account how seriously the violation affected the environment, whether it is a first-time or repeat violation, and how promptly the violation was reported to authorities. It also attempts to recover the calculated economic benefit gained by failure to comply with the laws in a timely manner.