The city of Farmington, Mo., agreed to pay a $61,566 civil penalty to the U.S. to settle violations of its wastewater discharge permits and the Clean Water Act related to nickel levels in sewage sludge that was applied to farms in four area counties, and ammonia levels in wastewater discharged from the city’s treatment plants.
Farmington’s violations of its National Pollution Discharge Elimination System (NPDES) permits and the Clean Water Act were documented during a January 2009 U.S. Environmental Protection Agency (EPA) inspection, according to an administrative consent agreement filed in Kansas City, Kan. EPA previously issued an administrative order for compliance on Feb. 1, 2010, requiring actions to be taken to address the violations.
During the 2009 inspection of Farmington’s East and West Wastewater Treatment Plants, a review of records noted that on 266 occasions between October 2006 and November 2008, sewage sludge from those facilities that was applied to agricultural land contained levels of nickel ranging from 59% to 791% above the regulatory ceiling level of 420 mg per kg, as specified by the Clean Water Act.
All told, the 266 sludge applications occurred at 29 different properties in Madison, Perry, St. Francois and St. Genevieve counties, involving more than 660 acres of agricultural land. Owners of properties that received the sludge were notified of the high nickel levels last year by the city of Farmington’s Public Works Department.
Sewage sludge that complies with federal and state standards can be beneficial as fertilizer or soil conditioner. However, sludge used for those purposes must meet certain regulatory limits. It must meet ceiling limits, which establish the highest level of pollutants that a single land application of sludge may contain, as well as cumulative loading limits, which establish a maximum level of pollutants that can be received at a given location without posing a significant risk to human health or the environment.
Although nickel content in Farmington’s 266 separate sludge distributions exceeded ceiling standards, EPA’s calculations do not indicate that the cumulative level of nickel that ultimately reached the 29 properties was exceeded.
In addition to the sludge issue, EPA’s 2009 inspection found that from February 2007 to May 2009, on a total of 43 occasions, Farmington’s wastewater treatment plants exceeded the levels of ammonia in their discharges of treated wastewater. Those exceedances, in violation of limits set by the facilities’ respective NPDES permits, ranged from 7% to 2,013%, the inspection noted. Farmington’s East Wastewater Treatment Plant discharges its treated wastewater to the Kennedy Branch of Wolf Creek, while the West Wastewater Treatment Plant discharges to an unnamed tributary of the St. Francois River.
Source: U.S. EPA
