Pennsylvania Code › Title 25 - ENVIRONMENTAL PROTECTION › Part I - Department of Environmental Protection › Subpart C - Protection of Natural Resources › Article II - Water Resources › Chapter 109 - SAFE DRINKING WATER › Subchapter G - SYSTEM MANAGEMENT RESPONSIBILITIES › Section 109.703 - Facilities operation

Current through Register Vol. 54, No. 28, July 13, 2024
(a) Public
						water system facilities approved by written permit from the Department shall be
						operated in a manner consistent with the terms and conditions of the permit to
						achieve the level of treatment for which the facilities were
						designed.
(b) For surface water or
						GUDI sources, a public water supplier using filtration shall comply with the
						following requirements:
(1) Water suppliers
						using conventional or direct filtration shall, prior to returning a filter to
						service, filter-to-waste for one full filter volume and until the filter bed
						effluent turbidity is less than 0.30 NTU at the normal production flow rate.
						Water suppliers may implement filter-to-waste for a period of time less than
						one full filter bed volume if an alternate operating technique is properly
						utilized to minimize the postbackwash turbidity spike to less than 0.15 NTU.
						Alternate techniques may include extended terminal subfluidization backwash,
						permitted addition of coagulant during the backwash or a post-backwash offline
						filter resting period. Water suppliers implementing alternate techniques shall
						keep records to document consistent and proper utilization of the
						technique.
(2) A water supplier
						using slow sand filtration shall, following sanding, scraping or resanding of
						slow sand filters, filter-to-waste until one of the following occurs:
(i) The filter bed effluent turbidity is less
						than 1.0 NTU at the normal production flow rate.
(ii) A reduction in turbidity is achieved
						when the source water turbidity is less than 1.0 NTU.
(3) A water supplier using diatomaceous earth
						filtration shall, following backwashing and recoating of diatomaceous earth
						filters, filter-to-waste until one of the following occurs:
(i) The filter bed effluent turbidity is less
						than 1.0 NTU at the normal production flow rate.
(ii) A reduction in turbidity is achieved
						when the source water turbidity is less than 1.0 NTU.
(4) For a conventional or direct filtration
						facility permitted prior to March 25, 1989, without filter-to-waste capability,
						the Department, upon the supplier's request, may allow the supplier to utilize
						other operating techniques which minimize the initial increased turbidity peak
						when a filter is initially placed back into service after backwashing. The
						technique, which may include filter settling periods, ramping open the effluent
						valve or use of a coagulant in the backwash water, shall be justified by a
						filter performance study approved by the Department.
(5) A system with filtration facilities shall
						implement a filter bed evaluation program, acceptable to the Department, which
						includes an evaluation of filter media, filter bed expansion, valves, surface
						sweep and sampling of filter turbidities over one entire filter run. The
						results of the evaluation shall be maintained on file and submitted to the
						Department upon request.