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RUMBLES - September 2015

feature This Grand Valley Transit Bus is one of a fleet that uses biogas produced at the Persigo Wastewater Treatment Plant and piped to Grand Junction’s slow fill fueling site. A Legacy of Excellence and Innovation RUMBLES SEPTEMBER 2015 | 15 do so at older treatment facilities usually requires significant upgrades. Over the years, the VFDs have been replaced with reliable units that are the size of a bread-box, and the alarm system now notifies plant staff of equipment failures on their cell phones. The excess methane was the last stronghold from the original plant configuration. Now, putting all of the methane gas produced at the facility to beneficial use has finally become a reality. In 2006, the City of Grand Junction began researching a biogas project that would allow methane gas produced at the wastewater treatment plant to be used as vehicle fuel. Currently, the facility produces approximately 120,000 cubic feet per day of methane gas in the anaerobic digestion process. Since plant startup in 1984, only a small amount of the methane gas was able to be used to fuel boilers that heat the digestion pro-cess, with the vast majority of the gas being flared off. In order to make this project a reality, a three-step implementation plan was created: • Installation of a compressed natural gas (CNG) fueling station connected to the natural gas public utility; • Investment in CNG vehicles; and • Converting wastewater biogas into natural gas quality vehicle fuel to be used by both city and county munic-pal vehicles. In 2009 the city faced vehicle fuel budget shortfalls with the escalating price of diesel fuel. This re-invigorated the CNG project discussions as fleet managers looked for ways to reduce fleet costs, environmental impacts, and reliance on imported fuels. CNG represented a technically and economically viable substitute for diesel fuel with the added environmental benefits and energy self-sufficiency. Steps 1 and 2 With no CNG fueling stations on Colo-rado’s Western Slope, the City of Grand Junction took a leap of faith in those early years by promoting the purchase of CNG fleet vehicles, while simultane-ously figuring out how to build a fuel-ing station—which comes first? For Grand Junction, the answer was both, with the hope that the pieces would all fall together at the right time. The first CNG solid waste trucks were delivered in 2011, within days of the CNG fueling station coming online. The CNG fueling station, located at the Municipal Services Campus in Grand Junction, was completed in the spring 2011 and obtained its fuel source from the public utility system. Funding for the $1.4 million project came from a number of sources including the City • Full-service dam engineering for more than 150 years; 60 years in North America • Recent dam projects span over 30 countries on 5 continents • Technical depth with local delivery for all major dam types, with advanced modeling and methods • Integrated water-resource services over the full life cycle • Hydropower services offering the full range of project development services, from LOPP, planning, fi nal design, and commissioning Contact: Jennifer.House@ch2m.com | 505.855.5257 | ch2mhill.com © 2014 CH2M HILL WBG103013093646DEN


RUMBLES - September 2015
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