Current through Register Vol. 24-06, March 15, 2024
(1) A discharge from a facility is considered
to have a risk for aquatic toxicity and to need an effluent characterization
for acute and chronic whole effluent toxicity if the facility or discharge meet
any of the following criteria:
(a) Uses,
stores, produces as a product or waste, or transfers any hazardous substance
listed in 40 C.F.R.
302.4 with a statutory code of 1 or 2
(referring to Sections 311(b)(4) or 307(a) of the Clean Water Act) unless:
(i) The permittee demonstrates to the
department's satisfaction that the facility is designed and managed so that
these substances are kept physically separated at all times, including spills
or any other accidental release, from any part of the wastewater collection,
treatment, or discharge system; or
(ii) The amount of any hazardous substance at
the facility is never more than the statutory reportable quantity listed in
40 C.F.R.
302.4;
(b) Discharges in its effluent any toxic
pollutant listed in Appendix D of 40 C.F.R. Part 122 for which there are no
water quality criteria for aquatic life protection listed in
40 C.F.R.
131.36(b)(1) or WAC
173-201A-040(3);
(c) Belongs to an
industry category identified in 40 C.F.R. Part 122, Appendix A;
(d) Is a municipal sewage collection and
treatment system which receives a discharge from any industry category
identified in 40 C.F.R. Part 403, Appendix C;
(e) Except for permittees with whole effluent
toxicity limits or permittees that have no whole effluent toxicity limit
because of the determination in WAC
173-205-120(1),
any facility which exceeded the acute or chronic whole effluent toxicity
performance standard within the last five years;
(f) Any facility with suspected toxicity
because of apparent damage to aquatic biota; or
(g) Any other discharger that the department
determines has the potential to discharge toxics in toxic amounts.
(2) The following types of
discharges are excluded from requirements for whole effluent toxicity
characterization unless subsection (1) of this section applies:
(a) Once-through noncontact cooling water
without biocides;
(b) Drinking
water treatment plant effluent;
(c)
Dewatering of sand or gravel mining operations;
(d) Sump pump discharges of groundwater or
rain water only;
(e) Construction
dewatering;
(f) Discharges from
fish hatcheries and other aquaculture;
(g) Seafood processors; or
(h) Any other discharge that the department
determines does not have the potential to contain toxics in toxic
amounts.
(3) A chronic
whole effluent toxicity characterization is not necessary in any permit if the
effluent has been or will be characterized for acute whole effluent toxicity
and if the discharge receives at least one thousand to one dilution at the edge
of a mixing zone assigned in accordance with WAC 173-201A-100.
Statutory Authority:
Chapter
90.48 RCW and
40 C.F.R.
122.44. 93-20-110 (Order 91-54), §
173-205-040, filed 10/6/93, effective
11/6/93.