Membrane Challenge Studies, Cartridge Filter Systems, and Alternative Membrane Filter Monitoring

Public water systems must conduct challenge testing for membrane and cartridge filtration systems that are installed to remove Cryptosporidium and Giardia. These tests evaluate how efficiently each membrane model or cartridge filter system removes pathogens and allows the TCEQ to establish a log removal value (LRV_C-Test).

Membrane and cartridge filter manufacturers must provide a non-destructive performance test (NDPT) and quality control release value (QCRV). The NDPT and QCRV help verify that all manufactured membrane models and cartridge filter systems that were not subject to challenge testing in the past will achieve at least the same log removal level as more current membrane models and cartridge filter systems that were challenge-tested.

Public water systems with membrane filtration systems will be approved for a removal-credit based on the lower of the LRV_C-Test and the log removal value that can be verified through direct integrity testing (LRV_DIT).

Challenge studies for the following membrane models and cartridge filter models for Cryptosporidium and Giardia removal have been reviewed and approved by the TCEQ:

Membrane Models

• Aqua MultiBore C-Series Membrane Module
• BASF Inge d5000 Ultrafiltration Membrane Module
• BASF Inge Dizzer Ultrafiltration Membrane Modules 
• CERAFILTEC Germany GmbH Blue Filtration 6.0 S - A7 Ultrafiltration Membrane Module
• Crosstek Ultressa CPM Ultrafiltration Modules
• Dow SFD-2880 Ultrafiltration Membrane Module 
• Dow IntegraFlo DW102-1100 Ultrafiltration Membrane Module
• Dow IntegraFlux SFD-2880XP Ultrafiltration Membrane Module
• GE ZeeWeed 700B-8060/UF10 and 700B-10060 UF Membrane Modules
• GE/Zenon ZeeWeed 1000 V4 Ultrafiltration Membrane Module
• GE/Zenon ZeeWeed 1500 Membrane Module
• Koch Targa II Ultrafiltration Element
• Koch Puron MP Ultrafiltration Membrane Module 
• Nanostone CM-151 Ultrafiltration Ceramic Membrane Module 
• Memcor L20N and L10N Ultrafiltration Membrane Modules
• Memcor L40N Ultrafiltration Membrane Module
• Memcor S10N Ultrafiltration Membrane Module
• Memcor L10Nv2, L20Nv2 and S10Nv2 Ultrafiltration Membrane Modules
• Pentair X-Flow Aquaflex HP and Xiga HP Membrane Challenge Study
• Pentair X-Flow Aquaflex and Xiga Membrane Challenge Study
• Purifics Ceramic Cuf Membrane Modules
• Scinor SMT 600-P50 and SMT 600-P80 Ultrafiltration Membrane Modules
• Scinor SMT 600-S26 Ultrafiltration Membrane Modules
• Suez ZeeWeed500D Membrane Module 
• Toray HFU-2020N Ultrafiltration Membrane Module
• Toray HFU-2020AN Ultrafiltration Membrane Module
• Toray HFU-B2315AN Ultrafiltration Membrane Module
• Toray HFUG-2020AN Ultrafiltration Membrane Module 
• Toray HFUG-B2315AN Ultrafiltration Membrane Module
• UNA 620A Hollow-Fiber Microfiltration Membrane

Cartridge Filter Models

• Graver QCR II Cartridge Filter with LPF-Series Housings
• Graver QCR II Cartridge Filter with GLP-Series Housings
• Harmsco HC/170 Cartridge Filter 

Membrane Systems

The following table shows the current membrane systems with their TCEQ-approved credit values for pathogen removal:

Cartridge Filter Systems

The following table shows the current cartridge filter systems with their TCEQ-approved credit values for pathogen removal:

Any manufacturer seeking to distribute a membrane or cartridge filter in the state of Texas must send the challenge study for the particular model to TCEQ for review and approval prior to installation. Challenge studies may be mailed to the following address:

Texas Commission on Environmental Quality
Technical Review & Oversight Team (MC-159)
PO Box 13087
Austin TX 78711-3087

For more information about these requirements see Title 30, Texas Administrative Code, Section 290.42(g)(2)-(3) .

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Alternative Methods for Monitoring Individual Filter Effluent from Membrane Units used for Pathogen Removal

For public water systems (PWS) treating surface water or groundwater under the influence of surface water and utilizing a membrane filtration system for pathogen removal, the PWS must employ a membrane system designed to conduct and record continuous indirect integrity monitoring by using the Hach FilterTrak Method 10133 on each membrane unit. The Hach Filtertrak Method 10133 specifies the use of the Hach FilterTrak (FT) 660 laser turbidimeter.  

The Hach Company ceased producing the FT 660 turbidimeter in 2018. Water systems which continue to use the FT 660 turbidimeter will meet the requirements specified in 30 TAC §290.42(g)(3)(C) and 30 TAC §290.111(f)(3)(B). For water systems replacing or installing a new turbidimeter on the individual filter effluent of a membrane unit used for pathogen removal, both 30 TAC §290.42(g)(3)(C) and 30 TAC §290.111(f)(3)(B) contain a provision which allows for the use of an alternative technology to monitor the quality of the water produced by a membrane unit. This provision could also be used to approve another parameter besides turbidity if adequate documentation can be presented. Equipment manufacturers must apply for and receive approval from the TCEQ prior to the use of an alternative monitoring method to measure individual filter effluent from membrane filtration units used for pathogen removal credits at a PWS in Texas. A manufacturer must establish that an alternative monitoring method is comparable to the Hach FilterTrak Method 10133 and is adequate for meeting the requirements in 30 TAC §290.111(f)(2)(D)(v) for reading low-level measurements commonly seen in water produced from membrane units (ex. - turbidity measurements of 0.15 NTU and lower). An alternative monitoring method must also meet requirements specified in 30 TAC §290.119(b) for acceptable methods.

Comparability studies have been reviewed and approved by the TCEQ for the following monitoring equipment models:

• Lovibond PTV 2000 (on-line Red LED) and PTV 6000 (laser) turbidimeters 
• Hach TU5400 sc (laser) turbidimeter 
• AMI Turbiwell White LED (W/LED) turbidimeter
• Hach TU5300 sc (laser) turbidimeter

Alternative Membrane Filter Monitoring Methods

The following table shows the current TCEQ-approved membrane filter monitoring method for each equipment manufacturer (make and model) and the TCEQ approval date:

Any manufacturer seeking to distribute an instrument to be used as an alternative monitoring method to measure individual filter effluent from membrane filtration units used for pathogen removal in the state of Texas must send comparability study information for the particular model to the TCEQ for review and approval prior to installation. The information may be mailed to the following address:

Texas Commission on Environmental Quality

Technical Review & Oversight Team (MC-159)

P.O. Box 13087

Austin TX 78711-3087

A manufacturer of an alternative method technology instrument to be used for compliance monitoring of individual filter effluent from membrane filter units used for pathogen removal is required to obtain approval from the TCEQ for the alternative method technology instrument. TCEQ review and approval is required prior to the use of an alternative method technology instrument by a PWS in the state of Texas utilizing a membrane filtration system for pathogen removal, even if an instrument or related method has already received approval from another agency. For example, if an instrument or related method is approved by the United States Environmental Protection Agency (USEPA) under the USEPA alternative testing procedure (ATP) program and the ATP approval is published in the Federal Register, a manufacturer is still required to obtain TCEQ approval for the use of an alternative technology to monitor the quality of water produced by a membrane filtration unit used for pathogen removal. The approved monitoring method must appear on this website in order to be eligible to be used for compliance monitoring of individual filter effluent from a membrane filtration unit in use for pathogen removal at a PWS in the state of Texas.

For more information about these requirements in Title 30, Texas Administrative Code see:

• 30 TAC §290.42(g)(3)(C) 
• 30 TAC §290.111(f)(3)(B)

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