The Oregon Department of Environmental Quality issued a $5,200 fine to the city of Philomath “for discharging wastes from its water treatment plant without a permit.”
In a June 27 letter to the city, DEQ wrote, “Specifically, on at least one day, plastic filter beads escaped from the treatment plant’s filters and discharged to an oxbow of the Marys River.”
Philomath Public Works Director, Kevin Fear, said the issue was related to the aging wastewater treatment plant.
“The plant is nearly 40 years old and does have issues and no amount of maintenance can prevent this,” Fear said in an informational report to the Philomath City Council. “The screens are checked almost daily and samples from the alum ponds are retrieved two or three times a week for compliance monitoring. The seals are changed yearly with the cleaning of the clarifier tank, which houses the media.”
Alum is a shortened term for potassium aluminum sulfate, which is used to treat water to improve clarity and quality.
“DEQ issued this penalty because the discharge of plastic filter beads poses a risk to aquatic life,” DEQ reported in its letter to the city. “Small plastic particles, such as filter beads, can be ingested by fish, birds and other animals causing digestive obstruction, impaired reproduction and other adverse biological effects, including death.”
Philomath is in the beginning stages of its construction of a new water treatment plant.
“The new water treatment plant will have a membrane filter and will not have media of any type to discharge so the risk of this issue recurring will be eliminated once the project is complete and the new plant is online,” Fear said.
Fear said the root issue involved an angle iron which had bent slightly “allowing the screen to lift and separate from the seal during a backwash cycle, allowing a few media beads to escape.”
Fear added that as of July 22, only one of 16 angle irons had bent.
“It is unknown why or how this occurred, and it was such a minor bend that it was not visible upon inspection after emptying the tank,” Fear said. “The operators were able to isolate sections of the screen and use a light to try to identify the problem and where it was coming from. The filter was left out of service until a replacement angle iron could be obtained and coated with approved coating.”
The filter was placed back in service about seven days from the discovery of the problem.
In the letter to the city, DEQ wrote that the agency “appreciates your efforts to correct the violation by repairing the screens on the filter to prevent additional beads from escaping in the future.”
Philomath’s efforts to fix the issue was taken into consideration when DEQ determined the amount of the civil penalty, the agency said.