12 Va. Admin. Code § 5-590-950

Current through Register Vol. 40, No. 22, June 17, 2024

Section 12VAC5-590-950 - Corrosion control or stabilization

A. Water that is unstable due either to natural causes or to the treatment applied to the water shall be stabilized.

B. Deposition of calcium carbonate film. The desired calcium carbonate film may be obtained by using either soda ash or caustic soda when the alkalinity of the water exceeds about 35 mg/L. Soft waters should be treated with lime to provide the required calcium. Soft waters that also have a low carbon dioxide content may need a mixture of lime and soda ash to provide both calcium and carbonate for the calcium carbonate film.

C. Phosphates or other corrosion inhibitors may be used for corrosion control when applied in accordance with manufacturer recommendations and when they meet the requirements of 12VAC5-590-515. Stock phosphate solution shall be disinfected in accordance with manufacturer recommendations unless the phosphate solution is fed directly from the covered shipping container.

D. Cathodic protection shall be acceptable for preventing or reducing corrosion of the inner surfaces of water storage tanks and standpipes and the outer surface of metal pipe.

E. Laboratory equipment shall be provided for determining the effectiveness of stabilization treatment and the concentration of chemicals in the treated water.

12 Va. Admin. Code § 5-590-950

Derived from VR355-18-009.11 § 3.32, eff. August 1, 1991; Amended, Virginia Register Volume 37, Issue 20, eff. 6/23/2021.

Statutory Authority: §§ 32.1-12 and 32.1-170 of the Code of Virginia.