City of Enid Municipal Landfill
Hannah Blankenship, Amethyst Kelly, Christian Ley Katie Schlotthauer
In August 2016, the Oklahoma Department of Environmental Quality (ODEQ) approached the Biosystems and Agricultural Engineering (BAE) Department at Oklahoma State University with a design project at the City of Enid (COE) Municipal Landfill. Four senior design students partnered to form Sustainable Solutions, responding to the opportunity to aid the COE landfill with its current erosion problem. Erosion concerns on the north-facing slope include scarce vegetative growth, sediment deposition at the base of the slope, rill formation, potential trash exposure, and contamination of the on-site stormwater pond.
The COE composting program operates on the premises of the landfill. Therefore, yard waste compost and woodchips are available for use as soil amendments. A stormwater detention pond nearby could also potentially be utilized for irrigation. If on-site resources are successfully utilized to quell the erosion concerns, a similar cost effective design could be applied at other erosion-prone sites across the state.
Some current low-cost solutions on existing landfills around the state have been ineffective in solving the erosion problem long-term. Previously at the COE landfill, sections of the north-facing slope have been hydroseeded with an alternative daily cover (ADC) machine, covered with woodchips, then sprigged and seeded. Another landfill erosion control method employed in Oklahoma includes layering straw and topsoil on the slopes. Many solutions succeed for a short time but eventually fail, and the erosion problem persists. Therefore, more sustainable designs using local, cost effective resources must be implemented in order to prevent detrimental impacts to the environment.
Research erosion prevention strategies that are applicable to Oklahoma landfills, and recommend a comprehensive design solution to mitigate erosion on the north-facing slope of the City of Enid Municipal Landfill.
Scope of Work
Sustainable Solutions designed a menu containing effective strategies to reduce erosion on landfill slopes. The menu contains solutions organized by severity of the erosion problem, anticipated cost, and longevity of solution. For the COE recommendation, the feasibility of using local resources such as soil, compost, woodchips, leachate, biosolids, and stormwater was determined through research and testing. Different erosion control designs were evaluated with computer modeling, and an on-site experiment was implemented on the north-facing landfill slope to determine the most promising solution.