12VAC5-630-430. Disinfection.
A. Private wells shall be disinfected before placing the well in service.
B. Methodology. Disinfection shall be accomplished by one of the following methods:
1. Maintaining a 100 mg/l solution of chlorine in the well for 24 hours utilizing the dosage rates set forth in 12VAC5-630-470.
2. Applying a quantity of water/chlorine solution to ensure a minimum of 100 mg/L of available chlorine throughout the well and immediate formation materials. Disinfection contact time shall be established on the basis of contact units, which are calculated as mg/L chlorine multiplied by hours of exposure. Contact time shall equate to a minimum of 1,000 contact units (50 mg/L chlorine x 20 hours = 1,000 contact units; 200 mg/L chlorine x 5 hours = 1,000 contact units; etc.).
Statutory Authority
§§ 32.1-12 and 32.1-176.4 of the Code of Virginia.
Historical Notes
Derived from VR355-34-100 § 3.9, eff. April 1, 1992; amended, Virginia Register Volume 41, Issue 4, eff. November 6, 2024.