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Oklahoma Administrative Code (Last Updated: March 11, 2021) |
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TITLE 252. Department of Environmental Quality |
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Chapter 656. Water Pollution Control Facility Construction Standards |
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Subchapter 23. Supplemental Treatment Standards |
SECTION 252:656-23-4. Membrane filtration
Latest version.
- Requests to use membrane filtration shall be reviewed and approved on a case-by-case basis. All membrane filtration systems shall meet the construction standards outlined in OAC 252:626-9-9(f) with the following exceptions:(1) Source water testing [Exception to OAC 252:626-9-9(f)(1)]. For wastewater and reuse applications, source water shall be defined as the effluent from a suitable treatment process designed according to the construction standards outlined in this chapter. This water shall be tested for all parameters that may affect membrane filtration and reuse water quality. Historic information shall be reviewed to determine water quality extremes that may be expected. Tabulated results of tests performed, summaries, and conclusions shall be submitted as part of the engineering report proposing membrane filtration.(2) Pilot plant verification study [Exception to OAC 252:626-9-9(f)(2)]. Prior to initiating the design of a membrane filtration system for wastewater or reuse applications, a pilot plant study is required to determine the best membrane to use. Submit pilot study protocol to DEQ for approval prior to initiating any pilot study. Pilot study duration shall be a minimum of three (3) months unless low variability in parameters critical to design warrant a shorter duration.(3) Log removal [Exception to OAC 252:626-9-9(f)(3)]. A pilot verification study shall be required for a membrane filtration system for wastewater or reuse applications only when removal credit is requested pursuant to OAC 252:656-27-3(a)(6).(4) Pretreatment [Exception to OAC 252:626-9-9(f)(5)]. Membrane filtration systems for wastewater and reuse applications shall be preceded by suitable biological treatment, disinfection to prevent biological growth and, if necessary, clarification processes designed according to the construction standards outlined in OAC 252:656-16 and OAC 252 656-17.(5) Turbidity monitoring [Exception to OAC 252:626-9-9(f)(10)]. Turbidity monitoring equipment shall be installed on all influent and effluent piping of membrane units. Continuous turbidity recording equipment shall be provided on the effluent piping and connected to an alarm system to warn operators of an excessive turbidity breakthrough for reuse applications.(6) Disinfection [Exception to OAC 252:626-9-9(f)(17)]. Membrane filtration systems shall be properly disinfected each time the membrane units are opened for maintenance and water shall not be sent into the reuse distribution system. Disinfectants prohibited by the membrane manufacturer shall not be used through the membranes.