12VAC5-590-510. Acceptable operating practices.
A. This section is not intended to be all inclusive but reflects the concern for the public health significance of certain practices related to waterworks operation.
B. Filter operation.
1. Gravity flow granular media filters designed for pathogen and turbidity removal shall not be operated without adequate chemical coagulation as determined by the department.
2. A waterworks utilizing gravity flow granular media filtration shall not vary the rate of filtration through any single filter above its design capacity unless approved by the department.
3. Gravity flow granular media filters equipped with filter-to-waste facilities shall not be returned to service after backwashing until a thorough rinsing period has occurred so that the filter-to-waste water has a turbidity less than or equal to 0.3 NTU.
4. All MF and UF technologies employed for pathogen removal shall demonstrate removal efficiency equal to the removal (log inactivation) credit given in Table 500.1. A direct integrity test acceptable to the department shall be conducted and include the following:
a. The direct integrity test capability shall be provided for each filter unit; and
b. The direct integrity test shall be conducted at least daily for each day the filtration unit is in operation.
C. All waterworks shall provide a minimum working pressure of 20 psigauge (psig) at all service connections.
D. The board recommends that all community waterworks in the Commonwealth deliver the optimum fluoride ion concentration as determined by the U.S. Department of Health and Human Services.
E. A waterworks owner shall provide the commissioner at least 90 days prior written notice of the intent to initiate or discontinue a program to provide the optimum fluoride ion concentration.
Statutory Authority
§§ 32.1-12 and 32.1-170 of the Code of Virginia.
Historical Notes
Derived from VR355-18-005.07 § 2.18, eff. August 1, 1991; amended, Virginia Register Volume 9, Issue 17, eff. June 23, 1993; Volume 37, Issue 20, eff. June 23, 2021.