At Monday’s meeting, the Carroll City Council directed the Public Works Department to initiate a study on effluent copper levels from the community’s wastewater treatment facility. According to Public Works Director Randy Krauel, staff recently completed collecting data to develop a Copper Biotic Ligand Model (BLM), which the Iowa Department of Natural Resources (DNR) uses to calculate site-specific copper discharge limits. Krauel says the plant currently releases too much copper in its effluent but is close to meeting regulations.
The city cannot continue discharging copper at this rate without taking some corrective action. Krauel says two options are available.
He notes that compliance could be a costly proposition requiring new treatment procedures. Krauel says there is an alternative.
The study could show the facility can meet existing regulations if enough effluent copper is not dissolved in the wastewater. A translator study typically takes up to a year to complete and requires at least 10 months of samples plus wait times for laboratory results at a minimum. Mayor Mark Beardmore indicated he and the council favored conducting the translator study in the hopes a substantial capital project could be avoided.
The council directed Krauel to begin the process of requesting the necessary amendment from the DNR to begin the dissolved metals translator study. Further action on this issue will occur when the study results are finalized.
