Oregon Administrative Rules
Chapter 340 - DEPARTMENT OF ENVIRONMENTAL QUALITY
Division 41 - WATER QUALITY STANDARDS: BENEFICIAL USES, POLICIES, AND CRITERIA FOR OREGON
Section 340-041-0175 - Water Quality Standards and Policies for this Basin
Current through Register Vol. 63, No. 3, March 1, 2024
(1) pH (hydrogen ion concentration). pH values may not fall outside the following range: all Basin streams (other than the main stem Colombia River): 6.5-9.0. When greater than 25 percent of ambient measurements taken between June and September are greater than pH 8.7, and as resources are available according to priorities set by the Department, the Department will determine whether the values higher than 8.7 are anthropogenic or natural in origin.
(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 340-041-0170: John Day River and Tributaries -- 500.0 mg/l.
(3) Minimum Design Criteria for Treatment and control of Sewage Wastes in this Basin:
Stat. Auth.: ORS 468.020, 468B.030, 468B.035 & 468B.048
Stats. Implemented: ORS 468B.030, 468B.035 & 468B.048