KANSAS CITY, MO. — HDR has been awarded a contract with Heartland Biogas, LLC, for the design, construction and startup of a 20-megawatt-equivalent anaerobic digester facility producing renewable natural gas (RNG) located in Weld County near LaSalle, Colo. HDR’s scope of services includes engineering design and construction, including subcontracting, procurement and startup operations. The Heartland Biogas project was developed by AgEnergy USA. EDF Renewable Energy, the owner of the project, participated in late stage development activities.

The organic wastes or feedstock include cow manure from local dairy operations and other organic wastes or “substrate” from the Denver metropolitan area, such as restaurant grease trap waste, spoiled products from retail grocers and food processing residuals. The waste conversion process will preclude the release of pollutants to the environment and will reduce the emission of significant amounts of greenhouse gas to the atmosphere. The digestion process of cow manure and substrates to the digester facility will produce three major outputs, including renewable natural gas, organic compost amendment, and liquid soil amendment product.

The Heartland digester facility is expected to be fully operational in 2015 and capable of exporting 1.5 billion cubic feet (BCF) of renewable natural gas annually, making it one of the largest anaerobic digester facilities in North America. Construction started in August 2013.

HDR Constructors, Inc., headquartered in Kansas City, Mo., and a wholly-owned subsidiary of HDR, Inc., is leading the project.

HDR also designed the Gills Onions Advanced Energy Recovery System facility located in Oxnard, Calif., which produces renewable fuel from onion waste. The project won the American Council of Engineering Companies’ Grand Conceptor award, ACEC’s highest award.