Membrane filtration units may be used in place of conventional filtration. Membrane filtration units must meet the following requirements:
- (a) A pilot study may be required to demonstrate the effectiveness of membrane filtration to achieve the required log removals of Giardia lamblia cyst, Cryptosporidium oocysts, and viruses a specified in rule 335-7-6-.04(e) on the proposed raw water source. The duration of the pilot study must be a minimum of 30 consecutive days. The pilot study shall be conducted during a time when raw water turbidity is historically high. A report on the pilot study must be submitted to the Department and approval obtained prior to the submittal of a construction application permit.
- (b) Maximum flow rates through membrane filtration units will be determined based on the lowest historical water temperature for the raw water source.
- (c) A minimum of two membrane filtration units is required.
- (d) Each membrane train shall have a turbidimeter and an instrument capable of measuring particles less than 3 micrometers installed on the effluent side of the train.
Author: Edgar K. Hughes, Dennis D. Harrison
Statutory Authority: Code of Ala. 1975, §§22-23-33, 22-23-49, 22-22A-5, 22-22A-6.
History: New Rule: Filed December 21, 1998; effective January 25, 1999. Amended: Filed May 2, 2000; effective June 6, 2000. Repealed and New Rule: Filed November 7, 2005; effective December 12, 2005. Amended: Filed December 18, 2007; effective January 22, 2008.