Eight Million Gallon Per Day Arsenic Removal Facility Started Up For Baldy Mesa Water District, California
One of the Nation's Largest Ion Exchange Arsenic Removal Projects for Drinking Water Will Deliver Low Lifecycle Costs and Optimal Use of Water Resources
Rancho Cucamonga, CA — Basin Water Inc. has announced that it has started up a new eight million gallon per day (mgd) arsenic removal facility to deliver safe, reliable drinking water for the Baldy Mesa Water District (BMWD) of Southern California. Based on the company's proprietary high efficiency ion exchange technology, the new facility will treat five of the District's eight groundwater wells to levels below the federally-mandated 10 part per billion (ppb) maximum contaminant level (MCL). Low waste rates made possible by Basin Water's technology will reduce costs and add millions of gallons of additional drinking water for the District's customers using the same resources. The new facility, which is expandable to 11 mgd, will be complemented by a second facility that will treat up to 3 mgd of water from the District's remaining wells. The second facility is expected to come online late this summer and will be used primarily to handle peak demand for drinking water. The first facility, located at the District's Avenal site, will be operated by Basin Water under a 10-year lease and services program that includes capital costs as well as operation and waste disposal. Under the agreement, Basin Water is guaranteeing compliance and operating costs for the term of the contract.
According to Joseph Ogg, Operations Manager for the Baldy Mesa Water District, the cooperative model used in the design, construction and operation of the new treatment facility is a key to assuring a reliable supply of drinking water at some of the lowest lifecycle costs for the customers of the District. "In contrast with a ‘build and handoff' approach to drinking water treatment infrastructure, the Basin Water approach to providing reliable water supplies involves guaranteed performance and guaranteed costs – based on their technology and their operational expertise," he said. "Baldy Mesa Water District has entered into a 10-year agreement with Basin Water for our Avenal facility under which the District pays a per acre-foot fee that includes both a lease and service component, with a minimum throughput of 5,000 acre-feet/year. This is the equivalent to 1.63 billion gallons per year. This agreement includes operation and maintenance of the ion exchange system, as well as transportation and disposal of waste and handling the multiple county, state and federal regulatory issues governing that waste. This specialized type of expertise does not exist within the District today and we would find it difficult and expensive to hire a person full-time to meet this need," he added.
The Baldy Mesa Water District, located in the high desert of Southern California, is an independent special district serving the residents of the city of Victorville and San Bernardino County in the Victor Valley. The District depends on groundwater for 100% of its water supply. This groundwater has naturally-occurring levels of arsenic ranging from 8 ppb to 16 ppb. New Federal regulations covering arsenic levels in drinking water have an MCL of 10 ppb. The new facility is removing arsenic to below 4 ppb and is flexible enough to allow the District to optimize costs versus water quality goals. A new building at the District's Avenal site houses three separate treatment trains rated at 2,000 gpm each, for a total capacity of 6,000 gpm (8 mgd). The facility is expandable to 8,000 gpm (11 mgd) with the addition of a fourth train. Waste rates, a key feature in controlling costs and maximizing the use of the District's natural resources, are in the 0.08% range – that is a 99.92% treated water recovery, compared with waste rates that could average in the 5% range for conventional arsenic treatment technologies.
According to Orlando Carreño, Vice President, Western Region of Basin Water, the Baldy Mesa Water District project is one of the first of its kind in removing arsenic from drinking water supplies via ion exchange. "Conventional ion exchange technology is not generally considered the solution of choice for removing arsenic from groundwater because of treatment reliability and high waste rates. The Baldy Mesa Water District reviewed many arsenic removal technologies available today prior to settling on Basin Water's high efficiency ion exchange," he said. "Because our technology was new, we had to prove its viability in the field for Baldy Mesa. This project involved a pilot-scale study that removed arsenic to non-detect levels and a demonstration facility that we ran for an entire year to prove the efficacy of our technology. The demonstration system, which went online in 2004, was the first arsenic removal system permitted in the State of California. We are excited about the opportunity this technology and our services offer the more than 3,000 communities in the United States who must treat their drinking water for arsenic," he added.
A second facility built by Basin Water at the District's La Mesa facility is near completion and is expected to go online in September. This is a smaller facility (2,000 gpm/3 mgd) that will treat two of the District's remaining wells and blend a third to reach the MCL levels required. For La Mesa, the District purchased the high efficiency ion exchange system outright from Basin Water. It will pay for water services under an operations & maintenance agreement based on acre-feet produced. This flexible approach to financing allows the District to make optimum use of its capital assets.
According to Doug Matthews, Engineering Manager, for the District, the start up of the Avenal facility represents the successful culmination of a process that was set in motion in 2001 when the United States EPA lowered the MCL for arsenic in drinking water from 50 ppb to 10 ppb. "When the new regulations were first promulgated, a lot of us in the industry were concerned about meeting them, because there were no really good technological solutions. We've come a long way," he said. "In the space of a few years."
"Basin Water has helped the Baldy Mesa Water District move from pilot-scale studies to full compliance without excessive capital outlay or investment of staff. Because we are working with a single company to build and operate our facility, we have established a clear line of responsibility for the performance of the facilities. We have also assured the future of our water treatment capability. The combination of optimized, versatile technology and a cooperative business model is a very effective approach for us," he added.
SOURCE: Basin Water