Sandia announces completion of mixed waste landfill cover construction

November 02, 2009

ALBUQUERQUE, N.M. - The Environmental Restoration Project at Sandia National Laboratories reports the successful construction of an alternative evapotranspirative cover at the Mixed Waste Landfill (MWL) in September. The 2.6-acre site is located in Technical Area 3 in the west-central part of Kirtland Air Force Base.

The protective cover consists of four engineered layers, including three layers of compacted soil and a biointrusion rock barrier that will keep burrowing animals out of the former disposal areas. Together, these four layers and the native plants will control water infiltration, thus isolating the wastes from the accessible environment. Because the cover is constructed without rigid layers, it can accommodate differential subsidence without undue impairment of its performance.

The MWL was established in 1959 as a disposal area for low-level radioactive waste generated by Sandia's research facilities. Low-level radioactive waste and minor amounts of hazardous waste were disposed in the MWL from 1959 through 1988. Approximately 100,000 cubic feet of waste containing about 6,300 curies of activity (in 1989) were disposed of in the landfill. Over time, the radioactive materials in the landfill decay and become less hazardous.

The MWL has been monitored since 1969 and actively studied since 1991. An extensive investigation effort provided the technical foundation for the determination that the landfill is not expected to contaminate groundwater and does not represent an unacceptable risk to human health and the environment. After the extensive investigation, public meetings and a public hearing, the New Mexico Environment Department (NMED) Secretary issued the final order in 2005 selecting an evapotranspirative cover with a biointrusion rock barrier as the selected remedy. After a review of competitive bids, Sandia awarded the construction contract to a local, small business. Cover construction was completed on schedule, near budget and without any safety incidents.

The NMED regulates the corrective action of the MWL as well as the implementation of institutional controls and long-term monitoring and maintenance. Sandia and DOE continue to provide quarterly progress reports to the NMED. In addition, the final order requires compilation of a report that re-evaluates the feasibility of excavation and analyzes the continued effectiveness of the selected remedy every five years. Construction of the MWL alternative cover will be documented in the Corrective Measures Implementation Report which will be submitted to the NMED for approval.

According to NNSA Sandia Site Office Federal Project Director Joe Estrada, "If it had not been for the personal perseverance of the project team, this mission would have withered. Now that the remedy is in place the team is looking forward to sharing lessons learned from the project."

The implementation of the selected remedy at the MWL is a critical step forward for the site. More than a decade of work and many personnel contributed to the success of the project. Although the cover is now constructed, monitoring work continues at the MWL. "The groundwater, soil gas and the cover will be monitored long-term to ensure performance and the protection of human health and the environment," said ER project task leader Mike Mitchell.
-end-
Sandia National Laboratories is a multiprogram laboratory operated by Sandia Corporation, an autonomous Lockheed Martin company, for the U.S. Department of Energy's National Nuclear Security Administration. With main facilities in Albuquerque, N.M., and Livermore, Calif., Sandia has major R&D responsibilities in national security, energy and environmental technologies, and economic competitiveness.

DOE/Sandia National Laboratories

Related Environment Articles from Brightsurf:

Detecting SARS-CoV-2 in the environment
Researchers have outlined an approach to characterize and develop an effective environmental monitoring methodology for SARS CoV-2 virus, that can be used to better understand viral persistence in built environments.

Can your diet help protect the environment?
If Americans adhere to global dietary recommendations designed to reduce the impact of food production and consumption, environmental degradation could be reduced by up to 38%, according to a new paper published in the journal Environmental Justice.

How do we disconnect from the environment during sleep and under anesthesia?
A series of new studies by researchers at Tel Aviv University's Sackler Faculty of Medicine and Sagol School of Neuroscience finds, among other important discoveries, that noradrenaline, a neurotransmitter secreted in response to stress, lies at the heart of our ability to ''shut off'' our sensory responses and sleep soundly.

Our pupil moves to the rhythm of the environment
Regular processes in the environment improve our eyesight.

New self-forming membrane to protect our environment
A new class of self-forming membrane has been developed by researchers from Newcastle University, UK.

COVID-19 and the built environment
Social distancing has Americans mostly out of the places they usually gather and in their homes as we try to reduce the spread of COVID-19.

A broad look at plant-environment interactions
Three plant science journals---the American Journal of Botany (AJB), Applications in Plant Sciences (APPS), and the International Journal of Plant Sciences (IJPS)---have joined efforts to provide a broad look at how plants interact with their environment.

New research looks at type 1 diabetes and changes in the environment
Studies have shown a rapid increase in new cases of type 1 diabetes worldwide.

Chemicals in the environment: A focus on mixtures
The real world is marked by multiple stressors, among them cocktails of chemicals.

Rubber in the environment
The tread on the tyre is worn out, new tyres are needed.

Read More: Environment News and Environment Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.