Sonoma County's Vintners Count On MetSorb(TM) From Graver Technologies to Remove Arsenic From Water


An innovative technology from Graver Technologies, LLC, is helping wine producers in the northern California wine country, including Sonoma, Napa, Lake and Mendocino Counties, meet tough new drinking water standards set by the U.S. Environmental Protection Agency (EPA) and California's Department of Health Services. Graver, in cooperation with their water treatment partners, has installed more than a dozen state-of-the-art treatment systems that use MetSorb(TM) HMRG adsorbent media to remove arsenic from the groundwater used in wine processing and vine irrigation.

MetSorb, a patented nano-titanium oxide adsorbent, is both extremely efficient and economical. Application of MetSorb in this wine-producing area is reducing both arsenic V and the more challenging arsenic III species without the need for traditional chemical oxidation. The product, a granular media deployed in treatment vessels, employs an adsorbent mechanism that attracts and tightly bonds arsenic V and arsenic III (present as anionic arsenate and neutral arsenite respectively) on the media surface and internal pore matrix of the granules. This advanced adsorption mechanism avoids the release of arsenic often experienced with traditional iron-based adsorbents and minimizes long-term media disposal liability. MetSorb also removes other contaminants of concern such as manganese, silica, vanadium, selenium and uranium.

"The unique groundwater quality associated with the Northern California wine country region presents significant arsenic removal challenges for most treatment technologies," says Jim Knoll, Graver Technologies' MetSorb manager, adding that Graver is very experienced with the Sonoma area, its water quality issues, its wine producers, the regulations and the regulating agencies. Continues Knoll: "The technical advantages of MetSorb allow us to remove both species of Arsenic (+5 and +3), from waters containing elevated pH and high concentrations of competing contaminants, such as silica. Understanding the characteristics of the ground water and the adsorbent capability of MetSorb have been critical to our success in this region."

Northcoast Waterworks, one of Graver's water treatment partners, elects MetSorb for its filtration systems. "In our area, the regulatory agencies do not allow on-site disposal of arsenic removed from the water so our only option is an adsorptive media," says Gene Broderick, president of Northcoast Waterworks. "After researching the available medias, we determined that MetSorb was the most effective product to design our systems around. We have several winery customers that have used metsorb successfully for a few years. Most wineries are classed as public systems and have to get county and state approval for their method of treatment. With the history of performance of the MetSorb media, these agencies are comfortable approving it. We continue to believe we can provide the best service for our winery customers by using this media."

Arsenic found in groundwater has been implicated in cancer risk. Experts believe that water in some geologic formations acquires arsenic by flowing through bedrock and dissolving iron or manganese oxides under anoxic conditions. For many years, federal and California drinking water standards for arsenic were 50 parts per billion (ppb). Following reassessments, EPA established a federal standard of 10 ppb that the agency required states to adopt by 2006. Toxicologists for California suggest that a far smaller concentration of four parts per trillion (ppt) would be safer for human health - equivalent to one drop in 25 million gallons - while EPA scientists recommend a goal of zero. Current commercial analytic detection methods cannot detect arsenic below 1,000 ppt. Experts expect that as technologies capable of detecting lower levels of arsenic become available, federal and state authorities will lower enforceable standards for the metal.

Graver Technologies LLC designs, develops, and manufactures an array of specialty products for critical ion exchange, separation, purification, and filtration processes. We specialize in the purification of power generation condensate, process and drinking water, and industrial fluids and gases. Graver is a member of The Marmon Group (a Berkshire Hathaway Company), an international corporation providing products and services around the world.MetSorb(TM) HMRG adsorbent media is a highly effective granular adsorbent that removes Arsenic III & V, and a wide variety of heavy metals including Lead, Chromium+6, Selenium, Uranium and Vanadium from aqueous sources. For more information on MetSorb® arsenic adsorbent media contact James Knoll at 410 596-9434, or by email at jknoll@gravertech.com.

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