Date Published: 12/03/2020 [Source]
The U.S. Department of Energy (DOE) Office of Legacy Management (LM) is in the preliminary stages of a pilot study on the feasibility of converting select disposal cell covers from rock riprap to an alternative type of cover referred to as an evapotranspiration cover.
At LM's Grand Junction, Colorado, Disposal Site, Frazier and colleagues from LM's Applied Studies and Technology group are testing the concept in a series of test plots. In March, the team mobilized a GeoProbe — a piece of machinery used to take core samples of soil from various depths — to extract multiple core samples through the cell cover and bedding material, down to the bottom of the radon barrier that limits radon gas from the contaminated materials from reaching the atmosphere. The data from these core samples will provide baseline measurements on current cell cover properties, before vegetation is established.
Once the team installs monitoring instruments into the cell, it will begin establishing vegetation in the test plots. After a lengthy monitoring period, ideally a decade or more, the team will once again extract core samples, this time to determine how the vegetation has impacted the cell — specifically, its ability to prevent groundwater contamination and limit radon release into the atmosphere.