Twin Oaks Landfill

HDR was commissioned by Brazos Valley Solid Waste Management Agency (BVSWMA) to perform siting, permitting, master plan and final design for Twin Oaks Landfill. Twin Oaks provides solid waste disposal for the region surrounding Bryan and College Station, Texas, previously serviced by the Rock Prairie Road Landfill, which reached capacity.

The Twin Oaks Landfill disposal areas utilize a hilltop location that minimizes the need to manage rainfall from offsite. They were intentionally sited south of Alum Creek, outside the flood plain, to prevent impacts to surface water. This required construction of a bridge across the creek, creating improved access on the property. Soils at the site were determined to have high clay content and select fill properties, suitable for use in the landfill liner and general building requirements.

The Twin Oaks site features an innovative layout and sustainable facilities. The landfill is located in an undeveloped rural area adjacent to a state highway that provides excellent access opportunities. To take advantage of the Highway 30 access, the highway adjacent to the site was improved and a new roadway system designed from the highway into the site, including the Alum Creek bridge.

A driver service area was thoughtfully designed for clients to utilize while at the site. The facility features handicap accessible restrooms, water fountains and vending machines so drivers can take a break and refuel with food and beverages.

A citizen's convenience area, separate from the active disposal area used by commercial vehicles, ensures that individual residents and small haulers receive quality service at the landfill. This area provides residents a safe, efficient option for disposing of waste and recyclable material at the landfill.

The landfill also houses an onsite facility to maintain landfill equipment including trucks, dozers and compactors. In order to protect the building's concrete floors during equipment maintenance, a portion of the floor includes steel rails for equipment with steel wheels or tracks.

With a forward-thinking design, Twin Oaks Landfill is the only LEED Silver Certified landfill in the nation. Onsite facilities feature white roofs to keep the buildings cool by reducing the "heat island" effect. Waterless urinals and low-flow fixtures reduce water consumption, while rain water is collected for irrigation. A provision for future installation of photovoltaic panels on the scale house roof was designed to capture solar energy.

A unique landfill presence, the Twin Oaks site is home to an endangered orchid species, the Navasota ladies'-tresses (NLT), which required extensive collaboration with regulatory agencies during landfill design. To protect the orchid, 141 acres of landfill property were deed-recorded to remain an undisturbed natural environment for the species.

Awards

• 2012 - Silver Medal, Environmental Category, Texas Council of Engineering Companies
• 2011 - Silver Landfill Management Excellence Award, Solid Waste Association of North America