When you think of the word “closure”, we think of conclusion, finality, or the end of a chapter. However, when it comes to landfills, closure represents the start of a new era of monitoring and maintenance. There are many considerations to be weighed when choosing the method of closure for a landfill, but one thing is certain: most decisions have the potential to have a lasting impact on the bottom line.
When it came time for Louisa County to construct a final closure cap on their 14-acre, unlined sanitary landfill, they turned to LaBella’s Waste & Recycling team (Joyce Engineering, at the time) for options and analysis. Our evaluation considered many factors, including gas and leachate control, groundwater and drainage, erosion and resulting maintenance, and initial and long term costs.
The County ultimately chose ClosureTurf ®, an artificial turf cap system. Though more expensive than a natural grass cover at the outset, ClosureTurf ® was calculated to provide a 3 year payback in reduced maintenance (mowing and erosion repair). Because the artificial turf requires less soil, there was room for an additional 45,000 cubic yards of waste in the permitted airspace, prior to closure.
With no artificial turf closure previously permitted in Virginia, the LaBella team led not only the design, but also the permitting process, ultimately delivering both on time and on budget. The resulting project is warrantied for 20 years.
From bottom to top, the closure system consisted of:
Intermediate cover soil foundation
50-mil LLDPE structured geomembrane layer (which will offer savings on future piggyback expansion lining)
Engineered artificial turf layer
0.5” sand ballast layer
Cement-lined stormwater conveyance channels
Click through the image gallery for more on the installation of the closure system.