Capping a Toothpaste Landfill and Constructing a New Landfill on Top

摘要

A manufacturer of silica gel was required by state regulators to close its existing filter cake landfill. The closure design needed to be flexible so that a new landfill could be constructed on top of the old one. A geotechnical evaluation of the existing filter cake was performed to determine the feasibility of constructing a landfill cap or a new landfill on top of the existing facility and to determine the amount of consolidation expected. The geotechnical evaluation determined that either closure or expansion was feasible if the site was graded to accommodate the consolidation of waste materials. About 0.7 m of consolidation would occur due to construction of the cap, and about 1.5 m if the tallest possible new landfill were constructed on top. Construction of the multiple layer cap and liner was completed in spring 2007.