SEPTEMBER 26, 2024 - CONSENT AGREEMENT
In August, October, and November 2019, the POTW exceeded its daily maximum and monthly average effluent limits for multiple pollutants including arsenic and ammonia. Such exceedances indicate that discharges from the Facility caused and/or contributed to cumulative in- plant toxicities impacting biological treatment.
On October 22, 2019, the POTW reported to NCDEQ its suspected reasons for the exceedances of the arsenic limits in the NPDES Permit during August 2019. The POTW reported that the food-to-mass ratio in the treatment system since August 2019 had decreased significantly, that midge flies have become an issue at the WWTP {blooms of these flies appear at WWTPs operating outside of steady state), and that Cormetech was discharging arsenic higher than normal.
On December 20, 2019, the Control Authority and Respondent entered into a consent order for significant non-compliance by the Facility, as defined at 40 C.F.R. ?{f){2){viii), including general exceedances of the arsenic pretreatment standards in the SIU permit between 2016 and 2017. The consent order did not cite Respondent for causing pass-through or interference.
On June 1, 2015, the Control Authority's NPDES Permit was renewed by NCDEQ. Daily maximum and monthly average effluent limits for thallium were added to the NPDES Permit due to high thallium concentrations being detected in the POTW effluent.
Throughout 2016, self-monitoring by the Facility and