Council authorizes city to seek updated industrial pretreatment local limits for wastewater plant

Brigham City Council authorized staff Feb. 6 to submit updated industrial pretreatment local limits for the city’s wastewater treatment plant, a technical action intended to protect plant operations and clarify the pollutants and loads the city will accept from industrial customers.

Jennifer Mickelson, the city’s wastewater treatment representative, explained the update moves the city from concentration-based limits to loading-based limits (pounds per day) for many pollutants, which staff and the city’s consultant developed in consultation with state regulators. The change is intended to allocate the treatment plant’s capacity more equitably among different industrial users — in particular to account for large, dilute waste streams from sizable manufacturers alongside smaller, higher-strength discharges.

Mickelson said several numeric limits are stricter than before because the plant is approaching capacity in certain pollutants; the city is also switching to best-management practices (BMPs) rather than a numeric oil-and-grease limit for food-service dischargers and adding aluminum to the list because the treatment process uses alum to meet phosphorus limits. Temperature will be removed from the local-limits list because it is controlled by other mechanisms.

Under state procedure, the city must provide a letter of support before the draft limits are sent to the state for public notice and final approval; the council authorized the mayor’s signature on that letter. Staff told the council the changes will not immediately force compliance changes for current permitted industries and that the new approach creates more realistic room to accept compatible new industrial customers in the future.

The council approved the request and completed a roll-call vote to authorize staff to submit the update to state regulators.