WAC 173-245-090
Schedule updates -- Monitoring -- Reporting. (1) By the anniversary date of its sewage treatment plant NPDES
permit, in conjunction with its annual assessment for prevention
of facilities overloading where applicable, a municipality shall
submit an annual CSO report to the department for review and
approval that:
(a) Details the past year's frequency and volume of combined
sewage discharged from each CSO site, or group of CSO sites in
close proximity. Field monitoring is necessary to estimate these
parameters. The report shall indicate whether a CSO site or
group of sites has increased over the baseline annual condition. If any increase has occurred, the municipality shall propose a
project and schedule to reduce that CSO site or group of sites to
or below its baseline condition;
(i) When a CSO site has been reduced to an average of one
overflow per year through use of storage or separation, the
department may consider reducing the monitoring requirement to
frequency verification;
(ii) If the selected CSO control project is at-site
treatment and discharge, the department may issue a modification
to the applicable sewage treatment plant permit or issue a
separate NPDES permit for that discharge. The permit or permit
modification must include effluent limits, flow capacity limits,
and reporting requirements. The total treated and untreated
annual discharge from an at-site treatment plant may not increase
above the baseline annual;
(b) Explains the previous year's CSO reduction
accomplishments; and
(c) Lists the projects planned for the next year.
(2) In conjunction with its application for renewal of its
applicable NPDES permit, the municipality shall submit an
amendment to its CSO reduction plan. The amendment shall
include:
(a) An assessment of the effectiveness of the CSO reduction
plan to date; and
(b) A reevaluation of the CSO sites' project priority
ranking; and
(c) A list of projects to be accomplished in the next five
years, based upon priorities and estimated revenues. The
department of ecology may incorporate such a schedule into an
administrative order or the applicable NPDES permit.
[Statutory Authority: RCW 90.48.110. 00-15-019 (Order 00-07), §
173-245-090, filed 7/11/00, effective 8/11/00. Statutory
Authority: RCW 90.48.035. 87-04-020 (Order DE 86-34), §
173-245-090, filed 1/27/87.]