Wis. Admin. Code Department of Natural Resources NR 811.59

Current through November 25, 2024
Section NR 811.59 - Taste and odor control

Waterworks which are designed and constructed to provide taste and odor control shall comply with any requirements provided for the following applicable methods:

(1) CHLORINATION. Chlorination is effective for the removal of some objectionable odors. Adequate concentration and contact time shall be provided to complete the chemical reactions involved. Excessive potential trihalomethane or other disinfection by-product production through this process shall be investigated by bench-scale testing prior to design.
(2) CHLORINE DIOXIDE. Chlorine dioxide may be used in the treatment of any taste or odor which is treatable by an oxidizing compound. Provision shall be made for proper storage and handling of sodium chlorite to eliminate any danger of explosion.
(3) POWDERED ACTIVATED CARBON.
(a) Powdered activated carbon may be added prior to coagulation to provide maximum contact time. Although facilities to allow the addition at several alternate points is recommended, in no case may carbon be added near the point of chlorine application.
(b) The carbon shall be added as a premixed slurry or by means of a dry-feed machine if the carbon is properly `wetted'.
(c) Continuous agitation or resuspension equipment shall be provided to keep the carbon from depositing in the mixing chamber/slurry storage tank.
(d) Dust control shall be provided.
(e) The required dosage of carbon in a water treatment plant depends upon the tastes and odors involved. Provisions shall be made for adding sufficient amounts to meet peak demands.
(f) Powdered activated carbon shall be handled as a potentially combustible material. It shall be stored in a building or compartment as nearly fireproof as possible. Other chemicals may not be stored in the same compartment. A separate room shall be provided for carbon feed installations. Carbon feeder rooms shall be equipped with explosion-proof electrical outlets, lights, and motors.
(4) GRANULAR ACTIVATED CARBON. The requirements for granulated activated carbon are in s. NR 811.49.
(5) COPPER SULPHATE AND OTHER COPPER COMPOUNDS. Continuous or periodic treatment of water with copper compounds to kill algae or other growths shall be controlled to prevent a level in excess of 1.0 mg/l as copper in the plant effluent or distribution system. Provisions shall be made for uniform distribution of the chemical.
(6) AERATION. The requirements for aeration are in s. NR 811.45.
(7) POTASSIUM PERMANGANATE. The department may approve application of potassium permanganate if the treatment will be controlled to insure that no residual color will be present in the finished water.
(8) OZONE. Ozonation may be used as a means of taste and odor control. Adequate contact time shall be provided to complete the chemical reactions involved. Ozone is generally more desirable for treating water with high threshold odors. Requirements for ozonation are contained in s. NR 811.54.
(9) OTHER METHODS. Any other methods of taste and odor control may be allowed by the department only after laboratory or pilot plant tests or both.
(10) FLEXIBILITY. Plants treating water known to have taste and odor problems shall be provided with equipment and multiple chemical addition points to provide several alternative control processes.

Wis. Admin. Code Department of Natural Resources NR 811.59

CR 09-073: cr. Register November 2010 No. 659, eff. 12-1-10.

Refer to subch. VI, for requirements for the storage, handling and application of chemicals in treating surface waters.