By Kristie Wilhelm and Carol Becker

The Package Drinking Water Treatment Systems (PDWTS) Environmental Technology Verification (ETV) Pilot was developed to benefit small communities by verifying the performance of pre-engineered drinking water treatment technologies and to facilitate the regulatory approval of innovative technologies. The U.S. Environmental Protection Agency (USEPA) and NSF International cooperatively administer it.

During the past four years, both USEPA and NSF have completed development of the pilot’s operational procedures, including eight contaminant-specific testing protocol documents and 18 technology-specific test plan documents. One additional protocol and nine additional test plans are under development and expected to be completed in September 2000. The pilot has approved 18 applications for verification tests involving 15 package drinking water treatment systems.

The Safe Drinking Water Act (SDWA) requires the USEPA to set numerical contaminant standards and treatment and monitoring requirements to ensure the safety of public water supplies. Since many small communities have limited financial and technical resources available for SDWA compliance, package drinking water treatment technologies may offer a more affordable alternative to the construction of a new conventional water treatment facility or development of a new water supply.1,2

Package system usage
Package drinking water treatment systems are factory-assembled equipment, typically skid-mounted for easy transportation, requiring only minor plumbing and electrical hook ups for installation. PDWTS installations can be used successfully by small communities to meet such drinking water regulations as the Disinfectant/Disinfection By-products (DBPs) Rule, the Surface Water Treatment Rule, the Total Coliform Rule and possibly the pending Ground Water Rule.4

PDWTS are considered an alternative treatment technology by many states and are often required to undergo lengthy pilot studies from state-to-state.3 The Association of State Drinking Water Administrators (ASDWA) developed a protocol that established a process for approving new and alternative drinking water treatment technologies, including PDWTS. The ASDWA protocol recommends that manufacturers of PDWTS provide objective and verifiable test data that support the treatment system performance claims. The ASDWA protocol’s preference as to the source of these data is an accredited third-party testing organization.4

The USEPA allocated funds for the verification of PDWTS under its ETV Program in October 1995. The program is led by the USEPA’s Office of Research and Development and was established to accelerate the development and commercialization of improved environmental technologies through third party verification and reporting of performance. The program structure includes a five-year pilot phase, during which the USEPA and its partners will operate to identify new and efficient ways to verify environmental technologies while maintaining the highest credibility standards. This pilot phase runs through September 2000, at which time USEPA will make recommendations to Congress on whether, and in what form, such verification should continue. The pilot was specifically created to help small communities comply with the SDWA, to reduce the number of costly pilot studies required by states and to accelerate the regulatory approval process for alternative technologies.

This project is one of several USEPA ETV pilots aimed at establishing the quality and integrity of environmental data collection.

Protocols and verification
The organizational phase of the PDWTS ETV Pilot began shortly after the allocation of funding in October 1995. To establish the PDWTS verification program, NSF and USEPA obtained broad stakeholder input in developing widely accepted protocols and test plans for verification testing of PDWTS. To assure that quality data are reported, the pilot oversees verification testing in conformance with the established protocols and test plans.

Figure 1 lists the contaminant-specific protocols and technology-specific test plans that have been finalized.

To date, the pilot has approved 18 applications and Field Operations Documents (FODs) for verification tests involving 15 package drinking water treatment systems. Testing and report writing for one system has been completed, and eight more tests for six products are in the report-writing phase. Three systems are currently being tested and six more products are scheduled to commence verification testing in the first quarter of 2000.

The first technology verified under the pilot was the Calgon Carbon Corporation Sentinel™ Ultraviolet Reactor, R-11, Model 6-1. The technology was verified according to the procedures outlined in the USEPA/NSF ETV Protocol for Equipment Verification Testing for Inactivation of Microbiological Contaminants.5  The verification testing was conducted at the Mannheim Water Treatment Plant in Kitchener, Ontario, Canada. Cartwright, Olsen and Associates LLC served as the Field Testing Organization (FTO).

Completed and in-progress testing
There are seven membrane filtration tests and one ozone/advanced oxidation test completed and in the report writing phase. These tests verified claims for both physical removal and inactivation of microbiological contaminants. Gannett Fleming Inc. tested four membrane filters in Pittsburgh, Pa.; CH2M Hill tested one membrane system in Portland, Ore.; and Montgomery Watson tested two membrane systems—one with enhanced coagulation—in San Diego, Calif. Cartwright, Olsen and Associates LLC tested the ozone/advanced oxidation system in Minneapolis, Minn.  Manufacturers with completed tests are Aquasource North America (one system tested at two sites), Pall Corporation, F.B. Leopold Company, ZENON Environmental Inc. (two systems tested at three sites) and Osmonics Inc.

Two membrane filtration and one cartridge filter verification tests are in progress. The tests are being conducted to verify claims for physical microbiological contaminant removal. The FTOs involved are Montgomery Watson and Cartwright, Olsen and Associates LLC; manufacturers involved include Hydranautics, Ionics, and Rosedale Products Inc.

Scheduled testing
Six additional treatment systems have been approved to begin testing during the first two quarters of 2000. The tests are to verify claims for physical microbiological contaminant removal and microbiological inactivation. The FTOs involved in these projects are Gannett Fleming Inc., Cartwright, Olsen and Associates LLC and the University of New Hampshire. The manufacturers involved in testing include Chemical Services Company, Kinetico Inc. (two products at one site), Pall Corp., and Separmatic Filter Company (two products at one site). A summary of the manufacturers and the products involved is listed in Figure 2.

Applications pending
On Aug. 20, 1999, NSF requested proposals to conduct the protocol validation studies for technologies for which the market demand will likely occur in future years. NSF wanted to validate the protocols and the test plans associated with USEPA rules that may be completed after the pilot, including:

  • Ground Water Rule—November 2000,
  • Proposed Radionuclides Rule—November 2000,
  • Arsenic—January 2001,
  • Stage 2 Disinfectants/Disinfection By-Products Rule—May 2002, and
  • Stage 2 (Long-term) Enhanced Surface Water Treatment Rule—May 2002.

The protocols for which the USEPA and NSF desired validation and that address the above list of rules are on-site DBPs and their precursors, arsenic and nitrate (an ever-present contaminant).

In response to the request for proposal, NSF has received proposals to conduct validation studies for the arsenic, DBPs and on-site disinfection. There are currently 10 applications pending in association with the protocol validation efforts. Figure 3 lists protocols and test plans currently under preparation, with an expected finalization this year.

The pilot officially ends its “pilot-phase” period Sept. 30, 2000, and the USEPA expects it to become a program. The future of the project will depend on the real and perceived value of verification testing of the PDWTS by all stakeholders. One major change anticipated for the program is that funding for future testing will most likely be borne by the manufacturers, utilities and other organizations.

The PDWTS ETV Pilot benefits all stakeholders. State and federal regulators will benefit from having credible, independent test results on the performance characteristics of PDWTS.  The availability of the ETV Protocols will reduce the need for regulators to develop and implement testing protocols for each PDWTS under review. Equipment manufacturers will benefit by receiving an independent verification test and a verification report on USEPA and NSF letterhead that can be used for marketing or investment purposes. Manufacturers can gain cost benefits from fewer requests for site-specific pilot testing at the state level. Small water utilities will benefit through improved drinking water and compliance with the SDWA, as well as from faster state approvals.


  1. Campbell, S., “Package Plants for Small Systems: A Field Study,” Journal AWWA, p. 49, November 1995.
  2. Goodrich, J.A., et al., “Safe Drinking Water from Small Systems: Treatment Options,” Journal AWWA, p. 49, May 1992.
  3. America Water Works Association Research Foundation, A Summary of State Drinking Water Regulations & Plan Review Guidelines, Denver, Colo., 1989.
  4. Association of State Drinking Water Administrators, Final State Alternative Technology Approval Protocol, Washington, D.C., July 1996.
  5. U.S. Environmental Protection Agency, “Environmental Technology Verification Report: Inactivation of Cryptosporidium parvum oocysts in Drinking Water: Calgon Carbon Corporation’s SentinelTM Ultraviolet Reactor,” USEPA/600/R-98/160.

For more information
If you are interested in having a product verified under the pilot or are a utility interested in hosting an ETV test, contact NSF International at (800) 673-6275 or visit the websites at or etv/

About the authors
Carol Becker and Kristie Wilhelm are environmental engineers at NSF International’s Environmental and Research Services Group, where they are involved with this project. Becker holds a bachelor’s degree in civil and environmental engineering from the University of Michigan; Wilhelm has a bachelor’s degree in the same plus a master’s in environmental engineering from the University of Michigan. Both worked in environmental consulting before joining NSF and can be reached at the phone number above.


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