Current through Register Vol. 63, No. 3, March 1, 2024
(1) pH (hydrogen ion concentration). pH
values may not fall outside the following ranges:
(a) Marine waters: 7.0-8.5;
(b) Estuarine and fresh waters:
6.5-8.5.
(2) Total
Dissolved Solids. Guide concentrations listed below may not be exceeded unless
otherwise specifically authorized by DEQ upon such conditions as it may deem
necessary to carry out the general intent of this plan and to protect the
beneficial uses set forth in OAR 340-04l-0220: 100.0 mg/l.
(3) Nutrients in Clear Lake Watershed. In
order to preserve the existing high quality water in Clear Lake north of
Florence for use as a public water supply source requiring only minimal
filtration, it is the policy of the Environmental Quality Commission to protect
the Clear Lake watershed including both surface and groundwater, from existing
and potential contamination sources with the following requirements:
(a) The total phosphorus maximum annual
loading discharged into Clear Lake may not exceed 241 pounds per year from all
sources.
(b) The total phosphorus
maximum annual loading for the Clear Lake watershed may be deemed exceeded if
the median concentration of total phosphorus from samples collected in the
epilimnion between May 1 and September 30 exceed nine micrograms per liter
during two consecutive years.
(c)
Of the total phosphorus loading of 241 pounds per year specified in section (1)
of this rule, 192 pounds per year will be considered current background and
Department reserve and is not available to other sources.
(d) The total phosphorus maximum annual
loading discharged into Collard Lake may not exceed 123 pounds per
year.
(e) If water quality
monitoring within the Clear Lake watershed indicates degradation, the
Commission may require additional studies, corrective actions, or both, by
rule. Such corrective actions may include but are not limited to the
construction of sewage collection and off-site treatment and disposal
facilities.
(4) Minimum
Design Criteria for Treatment and Control of Sewage Wastes:
(a) During periods of low stream flows
(approximately May 1 to October 31): Treatment resulting in monthly average
effluent concentrations not to exceed 20 mg/l of BOD and 20 mg/l of SS, or
equivalent control;
(b) During the
period of high stream flows (approximately November 1 to April 30) and for
direct ocean discharges: a minimum of secondary treatment or equivalent
control, and unless otherwise specifically authorized by the Department,
operation of all waste treatment and control facilities at maximum practicable
efficiency and effectiveness so as to minimize waste discharges to public
waters.
Stat. Auth.: ORS 468.020, 468B.030, 468B.035 &
468B.048
Stats. Implemented: ORS 468B.030, 468B.035 &
468B.048
