Oregon Administrative Rules › Chapter 340 - DEPARTMENT OF ENVIRONMENTAL QUALITY › Division 41 - WATER QUALITY STANDARDS: BENEFICIAL USES, POLICIES, AND CRITERIA FOR OREGON › Section 340-041-0033 - Toxic Substances

Current through Register Vol. 63, No. 7, July 1, 2024
(1) Toxic
			 Substances Narrative. Toxic substances may not be introduced above natural
			 background levels in waters of the state in amounts, concentrations, or
			 combinations that may be harmful, may chemically change to harmful forms in the
			 environment, or may accumulate in sediments or bioaccumulate in aquatic life or
			 wildlife to levels that adversely affect public health, safety, or welfare or
			 aquatic life, wildlife or other designated beneficial uses.
(2) Aquatic Life Numeric Criteria. Levels of
			 toxic substances in waters of the state may not exceed the applicable aquatic
			 life criteria as defined in Table 30 under OAR
			 340-041-8033.
(3) Human Health Numeric Criteria.
			 The criteria for waters of the state listed in Table 40 under OAR 340-041-8033  are established to protect Oregonians from potential adverse health effects
			 associated with long-term exposure to toxic substances associated with
			 consumption of fish, shellfish and water.
(4) To establish permit or other regulatory
			 limits for toxic substances without criteria in Table 30 under OAR 340-041-8033  or Table 40 under 340-041-8033, DEQ may use the guidance values in Table 31
			 under 340-041-8033, public health advisories, and published scientific
			 literature. DEQ may also require or conduct bio-assessment studies to monitor
			 the toxicity to aquatic life of complex effluents, other suspected discharges
			 or chemical substances without numeric criteria.
(5) Establishing Site-Specific Background
			 Pollutant Criteria: This provision is a performance- based water quality
			 standard that results in site-specific human health water quality criteria
			 under the conditions and procedures specified in this rule section. It
			 addresses existing permitted discharges of a pollutant removed from the same
			 body of water. For waterbodies where a discharge does not increase the
			 pollutant's mass and does not increase the pollutant concentration by more than
			 3 percent, and where the water body meets a pollutant concentration associated
			 with a risk level of 1 x 10-4, DEQ concludes that the pollutant concentration
			 continues to protect human health.
(a)
			 Definitions: As used in this section:
(A)
			 "Background pollutant concentration" means the ambient water body concentration
			 immediately upstream of the discharge, regardless of whether those pollutants
			 are natural or result from upstream human activity.
(B) An "intake pollutant" is the amount of a
			 pollutant present in waters of the state (including groundwater) as provided in
			 subsection (C), below, at the time it is withdrawn from such waters by the
			 discharger or other facility supplying the discharger with intake water.
(C) "Same body of water": An
			 intake pollutant is considered to be from the "same body of water" as the
			 discharge if DEQ finds that the intake pollutant would have reached the
			 vicinity of the outfall point in the receiving water within a reasonable period
			 had the permittee not removed it. To make this finding, DEQ requires
			 information showing that:
(i) The background
			 concentration of the pollutant in the receiving water (excluding any amount of
			 the pollutant in the facility's discharge) is similar to that in the intake
			 water; and,
(ii) There is a direct
			 hydrological connection between the intake and discharge points.
(I) DEQ may also consider other site-specific
			 factors relevant to the transport and fate of the pollutant to make the finding
			 in a particular case that a pollutant would or would not have reached the
			 vicinity of the outfall point in the receiving water within a reasonable period
			 had the permittee not removed it.
(II) An intake pollutant from groundwater may
			 be considered to be from the "same body of water" if DEQ determines that the
			 pollutant would have reached the vicinity of the outfall point in the receiving
			 water within a reasonable period had the permittee not removed it. A pollutant
			 is not from the same body of water if the groundwater contains the pollutant
			 partially or entirely due to past or present human activity, such as
			 industrial, commercial, or municipal operations, disposal actions, or treatment
			 processes.
(iii) Water
			 quality characteristics (e.g., temperature, pH, hardness) are similar in the
			 intake and receiving waters.