The EPA has released a draft technical support document for a 60-day public comment period that would assist states and authorized tribes in adopting and implementing EPA’s 2018 national recommended Clean Water Act section 304(a) aluminum aquatic life criteria. Consistent with the latest scientific information, the national recommended acute and chronic aquatic life criteria for aluminum in freshwater are intended to be derived on a site-specific basis, using a calculator or look-up tables, and data inputs for pH, total hardness, and dissolved organic carbon (DOC). This document is a revision of the draft that EPA released in 2019 and incorporates input provided by the public during the previous comment period. EPA is releasing this second draft in order to maximize the opportunity for public input.
Using a question and answer format, the draft document aims to provide answers to implementation questions previously identified by states, authorized tribes, and other stakeholders. The Qs/As address processes of criteria adoption into water quality standards, monitoring, waterbody assessment and listing for impairments, and NPDES permitting, as they pertain to the 2018 recommended aluminum criteria. EPA anticipates that this technical support document will be beneficial to states and authorized tribes since the aluminum criteria is among the first calculator-based aquatic life criteria that EPA has published.
Comments can be emailed to EPA at wqs-implementation@epa.gov through February 6, 2022.
The draft TSD on EPA’s Water Quality Criteria website can be found here.