On December 14, 2016, EPA signed its proposed Kraft Pulp Residual Risk and Technology Review rule covering 40 C.F.R. Part 63, Subpart MM (a.k.a. “MACT II”) for recovery furnaces, lime kilns and smelt dissolving tanks at kraft pulp mills.

After conducting the required “8-year” review of the MACT II rule, EPA has concluded that the current PM and gaseous HAP emission limits do not need to be changed to meet the Clean Air Act residual risk requirements. However, EPA is proposing to reduce opacity limits as a result of additional technology review and to address startup, shutdown and malfunctions (SSM) in light of the 2008 Sierra Club v. EPA decision, which vacated SSM exemptions in 40 C.F.R. Part 63, Subpart A, the MACT General Provisions.

The key EPA proposals are:

  • Reduce opacity standard for recovery furnaces from 35% to 20% (this would also eliminate the need for the existing 20% corrective action level);
  • Reduce the excess opacity allowance for recovery boilers from 6% to 2%;
  • Reduce excess opacity allowance for lime kilns from 6% to 1%;
  • Change the reporting frequency for the above excess opacity allowances from quarterly to semi-annually;
  • Add requirements for recovery furnaces and lime kilns equipped with ESPs to monitor secondary voltage and secondary current (or, alternatively, total secondary power). The parameters would be averaged over the semi-annual period;
  • Require ESP and wet scrubber parameter monitoring for units equipped with both controls. ESP parameters would be secondary voltage and secondary current (or, alternatively, total secondary power) and the wet scrubber parameters would be pressure dropped and scrubber liquid flow rate on 3-hour averages; and
  • Eliminate the current SSM exemption language and require facilities to meet limits at all times (including periods of SSM) and provide alternative monitoring parameters for such periods.

EPA proposes a 60-day comment period beginning once the proposal is published in the Federal Register.