EPA issued an Administrative Consent Order (ACO) for NLMK Indiana (NLMK), Portage, Indiana, to address violations regarding the requirements of the Standards of Performance for Steel Plants: Electric Arc Furnaces and Argon-Oxygen Decarburization Vessels Constructed After August 17, 1983 (NSPS AAa), set forth at 40 C.F.R. 60.270a et seq., and the requirements of NLMK's Title V permit at its Portage, Indiana facility.
Specifically, NLMK exceeded the electric arc furnace shop (EAF Shop) opacity limit of its Title V permit (3% opacity on a six-minute average) and of NSPS AAa (6% opacity on a six-minute average). Additionally, NLMK failed to perform daily opacity readings, failed to perform daily opacity readings in accordance with Method 9, failed to perform daily opacity readings in accordance with Method 9 when the continuous opacity monitor was down, and failed to follow good air pollution control practices by failing to capture 100% of emissions from the EAF as required by NLMK's Title V permit.
During negotiations, NLMK undertook several projects to address the alleged violations. On December 31, 2016, NLMK completed installation of a new secondary canopy hood, replacement of the EAF Shop siding, installation of a three-part seal design at the roof-eave interface adjacent to the EAF, and installation of a full partition between the East and West Bays of the EAF Shop. The total cost of these projects was in excess of $4,000,000. On February 20, 2017, NLMK demonstrated comp