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EPA Disapproves Oregon’s Natural Conditions Criteria

August 13, 2013

The Environmental Protection Agency (EPA) disapproved Oregon’s natural conditions criteria late Thursday, August 8, 2013.  The disapproval follows a February 2012 ruling by Oregon federal court Judge Acosta, which required EPA to review Oregon’s temperature standard, which contained a natural conditions criteria provision and general natural conditions criteria.

Oregon’s natural conditions criteria, or a similar provision, has been in place since the 1970s.  These criteria allow the Department of Environmental Quality (DEQ) to set natural conditions as the water quality standard when the biologically-based (laboratory) water quality standard is higher than natural water conditions.  Many Oregon streams do not meet Oregon’s temperature standards.  As a result, relying on the (now disapproved) natural conditions criteria regulation, DEQ set water quality standards for certain watersheds that were based on natural conditions.  All water quality regulation was then based on meeting natural conditions, rather than a standard developed in a laboratory.

With EPA’s disapproval, DEQ can no longer set water quality standards that reflect natural conditions. Instead, DEQ must regulate point sources (i.e. industrial and municipal dischargers) to standards that are more stringent than natural conditions.  DEQ intends to require point sources to meet water quality standards that are below natural conditions using compliance schedules and variances.  Some additional details about how DEQ intends to approach point source regulation and permit renewals are provided in the DEQ’s August 8, 2013 fact sheet.

DEQ will not change targets, such as stream shade, for nonpoint sources (i.e. agriculture and forestry).  These targets are set out in its Total Maximum Daily Load and Water Quality Management Plans (TMDL).  A TMDL is a plan developed by DEQ that calculates the maximum amount of a pollutant that a water body can receive without exceeding water quality standards and allocates those pollutant “loads” to point and non-point sources within the watershed. DEQ currently looks to the Oregon Department of Agriculture and Oregon Department of Forestry to implement targets it develops to meet water quality standards through the TMDL process.

TMDLs that were developed based on temperature standards relying on the natural conditions criteria are also being challenged in litigation filed by the Northwest Environmental Advocates.

DEQ does not intend to immediately begin work on a new temperature standard.  However, EPA suggested three options for DEQ to respond to EPA’s disapproval of the natural conditions criteria.  One option is to implement temperature standards that do not account for natural conditions.  Another second option is to develop site-specific criteria for each of Oregon’s waterways.  A third option is to develop a methodology (i.e., science-based equation) that DEQ could use to derive standards reflective of the variations in streams across Oregon.  What DEQ will do remains to be seen.

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