2013 Issue

36 BCWTP has operated since 2006, delivering high purity drinking water to the District for delivery to the four AffectedMunicipalities. The high purity water quality has been well accepted by the public, with no taste complaints received by the District. The District is nearing construction completion of the Zone B and Lost Use facilities. They involve eight deep wells and one shallow well for feed water, ten miles of collection pipelines, the new Zone B/Lost Use treatment plant, treatedwater pipelines, and by-product water discharge pipeline. The new treatment plant, known as the Southwest Groundwater Treatment Plant (SWGWTP), also employs the high-tech reverse osmosis treatment process. These facilities will be complete and operational by mid-2013. They will provide water to the four Affected Municipalities, as well as all 17 member agencies of the District. Southwest Jordan Groundwater Project Water Deliveries The SWJVGPwill yield the following treatedwater amounts annually: Zone A (at BCWTP) 3,500 acre-feet (AF) Zone B (at SWGWTP) 3,500 AF Lost Use (at SWGWTP) 1,235 AF TOTAL 8,235 AF The Zone A water deliveries from BCWTP are committed, with allocations that were defined in the 2004 agreements, to the four Affected Municipalities. By-Product Water Discharges The reverse osmosis process of the BCWTP and the SWGWTP de- mineralize the feed water and removemost of the sulfate contami- nation, producing high purity drinking water. The mineral content of these waters is compared for illustration with the pristine water supplies currently available to the District, as follows: SOURCE Mineral Content (parts per million) Provo/Weber River Water 250-300 Southeast Salt Lake Valley Deep, Pristine Groundwater 200-300 BCWTP 250 SWGWTP 250 In demineralizing the feedwater to produce these high purity streams of drinking water, the reverse osmosis process at each of the two treatment plants produces two streams of water that leave the treatment plant: 1) the high purity treated water, and 2) a by-product water stream which contains most of the minerals and salts. The by-product water has created discharge concerns, even though its salinity is less than 10 percent of the salinity of Great Salt Lake waters. Zone A by-product water is discharged by Kennecott to its Magna Tailings Impoundment, where most of it is evaporated and some of it is discharged to Great Salt Lake under an existing discharge permit. During 2004-2005, theDistrict, the Trustee and Kennecott convened a Southwest Groundwater Stakeholders Forum (Forum), and held numerous meetings. As a result, the Forum recommended two possible alternatives for the SWGWTP by-product waste stream: (1) discharge to Kennecott’s tailings impoundment, or (2) discharge to the open waters of Great Salt Lake. Discharging to the open waters of Great Salt Lake had the potential for a longer-term operating situation for the District. However, environmental groups expressed concerns regard- ing concentrated selenium being discharged to Great Salt Lake. Selenium is a naturally occurring trace metal found in groundwaters throughout Salt Lake Valley, which would be concentrated about five times through the reverse osmosis treatment process. The District and the Trustee, again implementing a collaborative approach, convened an extensive group of stakeholders as the Great Salt Lake Water Quality Steering Committee (GSL Com). GSL Com included stakeholder interests representing environ- mental groups, bird and duck clubs, regulatory entities, potential dischargers, wastewater discharging entities, brine shrimp industry, mineral concentration industry, and others. GSL Com adopted this objective: to study the Great Salt Lake ecosystem and potential selenium discharges, and to recommend a selenium standard for Great Salt Lake which would be protective of the Lake’s ecosystem and environment. GSL Com convened a panel of expert scientists, identified a pro- gramof four study groups, and raised $2.6 million to fund the stud- ies. The study programwas conducted over the four year period of 2006-2009. GSL Com made recommendations to the Utah Water Quality Board, which in 2009 adopted a selenium standard as the first numeric standard for Great Salt Lake. The District submitted its application for Zone B discharge permit in November 2010. The District and the Utah Division of Water Quality held an extensive public information and public comment series during 2010-2011. It is anticipated that in 2013 a permit will be granted to the District for discharge to the open waters of Great Salt Lake. Summary The Southwest Jordan Valley Groundwater Project provides unique benefits to the public in Salt Lake Valley, including: containment A Case Study | continued from page 35