(EPA/540/1-89/002, U.S. Environmental Protection Agency, December, 1989), assuming a
reasonable maximal exposure (RME), and employing EPA Reference Doses (RfD) or doseresponse slope factors described in Integrated Risk Information System (“IRIS”) (primary
source) and Health Effects Assessment Summary Tables (“HEAST”) (secondary source).
(1) Acceptable risk criteria shall be calculated for each hazardous substance (“k”), released
from each medium (“j”), through each pathway (“i”) by summing specific risks to render
a cumulative estimation of risk as follows, regardless of target tissue or mode of action:
ΣΣΣR(i, j, k)
ij k
Where i = Pathway, e.g., inhalation, dietary, incidental ingestion, dermal, etc.)
j = Medai, e.g., surface water, ground water, soil, sediment, food/medicine, air, etc.
k = hazardous substance, e.g., analytes identified in the first column of the
following tables.
Pathway (“i”), medium (“j”), and hazardous substance (“k”)-specific risks (Ri, Rj, Rk,
respectively) shall be calculated by employing the appropriate human health risk scenario
which has been designed based on the future or current use of resources identified within
the nature and extent of contamination.
(d) Background level shall be determined by the Department based upon data and tests presented
by the site owner, operator, the Department, or other governmental entity acceptable to the
Department.
(e) In cases involving multiple chemicals with multiple health effects the Department may use the
federal cleanup law and regulations, rules and guidances related thereto as guidelines to
determine aggregate cleanup levels that are protective of human health and the environment.
(f) The Department may contract expertise, and may consult with state and federal agencies,
institutes of higher learning, and other entities with expertise in toxic cleanup and human or
environmental toxicology in order to determine clean up levels which are protective of human
health and the environment.
Legislative History-Adopted 12/22/03, Resolu. 2004-085; Readopted 8/01/06, Resolu. 2006-524.
34-1.12 Disposal of Hazardous Substances. Due to the emergency declared in 34-1.02, the disposal of
hazardous substances on the Reservation shall be limited as follows to protect human health and the
environment:
(a) No new facility shall be constructedi on the Reservation for permanent disposal of hazardous
substances:
(1) within 1000 feet of any wetland; or
(2) within 1000 feet of any intermittent stream, perennial stream, or other surface water
that directly or indirectly flows to streams designated as Class A or Class AA the
Spokane Tribal Water Quality Standards; or
(3) within 1000 feet of any aquifer recharge zone.
(b) A new facility for the permanent disposal of hazardous substances may be constructed outside
those areas identified in Subsection (a) only if:
(1) constructed in compliance with applicable federal or Tribal law, or if more stringent with
the laws of the State of Washington, for operating facilities for disposal of hazardous
substances as defined in this Chapter; and
(2) the Department first approves a closure plan for the disposal facility that complies with
the cleanup standards of this Chapter; and
(3) a performance bond in an amount that the Department determines to be sufficient to
achieve the cleanup described in the approved closure plan and which may be accessed
by the Department in the event the disposal facility operator fails to perform its duties
under the closure plan.
(c) A new facility for the temporary disposal of hazardous substances may be constructed within
those areas listed in 34-1.12(a) only if:
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Revised Spokane Law & Order Code, 5/14/2013