Two Small AZ Utilities Host EPA Arsenic Treatment Demo Projects

Two Arizona water utilities are among the 12 selected nationwide to participate in phase one of the U.S. Environmental Protection Agency’s Arsenic Treatment Technology Demonstration Program. EPA’s role in the program is to act as a broker or intermediary, arranging working relationships between small utilities with arsenic treatment needs and vendors or engineering firms having arsenic treatment technologies to demonstrate.

The two Arizona communities involved in the EPA program are Rimrock and Valley Vista in Yavapai County. Both communities’ water utilities are owned by the Arizona Water Company.

The program is in response to EPA’s awareness that small utilities, those with less than 10,000 customers, will need assistance in meeting the new arsenic standards. The program’s intent is to promote research and development of cost-effective treatment technologies and to provide technical assistance to small system operators to reduce compliance costs.

In an early phase of the program, EPA invited small water utilities to submit an application if they were interested in serving as demonstration sites for an arsenic water treatment technology. The participating utility would not get any EPA funding but, if selected, would benefit by having its water treated by an EPA-supported contractor demonstrating a treatment technology.

Bill Garfield, Arizona Water Company vice president, describes the kind of information the company’s utilities submitted to EPA. He says, “We provided information on water quality, flow rates, site plans including, for example, the size of the site, and whether liquid waste could be disposed of.”

He says they also provided information beyond what the application required, to show that the systems served households with incomes below the national medium. He says, “We felt that also would perhaps be a consideration — the affordability of water rates after arsenic is removed.”

EPA’s plan was to include utilities in the program with various source water quality parameters to reflect conditions across the United States. This would provide a range of opportunities to demonstrate and test different water treatment technologies.

Arizona’s participating utilities are small operations. Rim Rock’s flow is about 90 gallons per minute, and its water tests at about 50 parts per billion for arsenic, which is the existing maximum contaminant level. Valley Vista’s flow is between 40 to 50 gallons per minute and has 30 to 50 ppb of arsenic. The new arsenic standard to be met by January 2006 is 10 ppb.

Once utilities were selected, EPA requested that vendors, engineering firms and other interested entities involved in water treatment technologies submit program proposals. In preparing their applications, proposers referred to the list of participating utilities and checked the information the utilities submitted to EPA as part of their application process. Proposers could then better determine which utilities would best benefit from their treatment technologies.

Proposers submitted their proposals identifying one or more sites and provided information to support the claim that their treatment technology is compatible with the utility’s source water quality conditions. All technologies needed to be commercially available for purchase with no additional development work required

EPA then reviewed the proposals and determined which to fund, with the proposer or vendor receiving compensation for the technology. In effect, program proposers of treatment technologies get compensated for demonstrating their product to technology users.

The proposer participates in the installation and start-up of the treatment process including on-the-job training. Garfield says the contractors also worked through the process to obtain Arizona Department of Environmental Quality approval.

The utilities also have certain responsibilities to meet. For example, Garfield says that at Rim Rock, “We had to pay for the engineering and construction of the slab and for any structure or enclosures around the treatment plant. Plus we have to provide manpower resources to operate the plant during the term of the program.”

Both Arizona plants will be utilizing absorptive treatment technology but with different media. AdEdge, the contractor building the Rimrock plant, will be utilizing an iron media developed by Severn Trent. At Valley Vista, Kinetico, the contractor, will be using activated alumina as the treatment media.

Information gathered during the operation of the demonstration project will provide an opportunity to evaluate the reliability of the technologies for small systems and gauge the simplicity of the operation. Also the projects will help determine maintenance, operator skills and cost-effectiveness and will characterize treatment residuals. At the completion of the program the utilities will have the option of keeping the treatment system and continue its operation or modify it.

ADEQ is expected shortly to approve the Rim Rock site, and construction will begin shortly thereafter, with the Valley Vista project soon to follow.

Information about the performance of the various demonstration projects will be made available in publications, presentations and on the EPA web site. Bob Thurnau of EPA’s National Risk Management Lab says the information will enable small utilities who are having trouble finding the right treatment technology to search a database to match their water quality needs against what was done in the demonstration projects to find the best fit for their situation.

Thurnau says that although EPA support of demonstration projects is not new this project is breaking new ground. He says, “The size is one of key characteristics of this program. We have never worked at quite this magnitude before.”

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