Current through Register Vol. 60, No. 12, December 1, 2021
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:
Dissolved Solids. Guide concentrations 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-0230: All Fresh Water Streams and Tributaries (other
than the main stem Columbia River) -- 100.0 mg/l.
Minimum Design Criteria for Treatment and
control of Sewage Wastes in this Basin:
During periods of low stream flows (approximately April 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): 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
Or. Admin. R.
DEQ 17-2003, f. & cert.
ef. 12-9-03; DEQ 2-2007, f. & cert. ef.
Stat. Auth.: ORS 468.020, 468B.030, 468B.035 &
Stats. Implemented: ORS 468B.030, 468B.035 &