COMMISSION IMPROVES PROCESS FOR DECISIONS
TO REDUCE AND ELIMINATE MIXING ZONES
FOR BIOACCUMULATIVE CHEMICALS OF CONCERN
The Ohio River Valley Water Sanitation Commission today approved revisions to the Pollution Control Standards for industrial and municipal wastewater discharges into the Ohio River.
Among the revisions approved after much consideration and public outreach, were changes to existing ORSANCO regulations on mixing zones for bioaccumulative chemicals of concern (BCCs).
Since October 16, 2003, new dischargers of any of 22 listed bioaccumulative chemicals of concern (including mercury) into the mainstem of the Ohio River have been ineligible for a "mixing zone" in which the wastewater discharge is allowed to mix with river water before meeting instream water quality standards. This prohibition, which requires that the water quality standard for mercury be met at the "end-of-pipe," remains in place for new dischargers after 2003.
For those facilities discharging wastewater into the Ohio River prior to 2003, ORSANCO's former standards imposed a ban on mixing zones after October 16, 2015, but allowed ORSANCO to grant a variance allowing continued mixing zones after that date for such discharges, on a case-by-case basis. To date, ORSANCO has approved two such variances, both in the state of West Virginia.
The revision approved today makes several changes to improve the process for decisions to reduce and eliminate mixing zones for bioaccumulative chemicals of concern:
1. The October 16, 2015 date for the imposition of the mixing zone prohibition for pre-2003 dischargers of BCCs is eliminated, as is the opportunity to seek a variance from ORSANCO from that prohibition.
2. The goal of elimination of mixing zones for BCCs remains, and is advanced by requiring a more rigorous demonstration by the discharger than the former variance procedure. The goal as restated is to eliminate such mixing zones "as soon as is practicable," considering technological and economic feasibility on a case-by-case basis. Whether to allow any mixing zone for the pre-2003 dischargers of BCCs will be made during the state wastewater permit process, and will depend on what measures the discharger has taken and proposes to take during the next permit cycle to reduce or eliminate the need for a mixing zone, as well as the concentration, duration, and exposure conditions for each BCC for which a mixing zone is sought. Unlike the current ORSANCO variance process, the justification for any mixing zone will be subject to review during each permit renewal or reissuance, and is subject to more formal opportunities for public comment and administrative and judicial review of the permitting decision.
"The Commission remains committed to the elimination of all mixing zones for bioaccumulative chemicals of concern," stated Commission Executive Director Richard Harrison. "Strengthening the demonstration by the discharger of the actions that they have and will take to reduce and eliminate the use of mixing zones, will lower mercury loading into the Ohio River in a more robust and transparent way than under the former standard, which allowed variances on the basis of a less rigorous test."
In other action, the Commission supported a June 15, 2015 request of a new Advisory Committee representing conservation, watershed and wildlife organizations within the Ohio River basin. The Commission Chair will appoint an ad-hoc committee to develop a specific proposal for the advisory committee for consideration and action at the February 2016 Commission meeting.
"The sense of the Commission is that providing an ongoing advisory presence for these interests has merit, and the Commission has authorized creation of an ad hoc committee to work on the concept and to bring a specific proposal for establishing such a committee to the full Commission at the February 2016 meeting," said Commission Chair Douglas Conroe. "The thousands of public comments received during the recent triennial review of ORSANCO's Pollution Control Standards reflect a significant public interest in ORSANCO's mission, and creating ongoing opportunities for dialogue, input, and education through the advisory committee process is an important component of implementing ORSANCO's mission.
ORSANCO, headquartered in Cincinnati, Ohio, is an interstate water pollution control agency for the Ohio River and its tributaries. Member states include Illinois, Indiana, Kentucky, New York, Ohio, Pennsylvania, Virginia, and West Virginia. The federal government is also represented. For further information, contact ORSANCO at 513-231-7719, or visit our website at www.orsanco.org.
