Las Pulgas Landfill Phase I Liner Evaluation, Marine Corps Base (MCB) Camp Pendleton, CA.

The overall objective of this task order was to provide technical support services pertaining to the completion of a liner evaluation for Phase I of the Las Pulgas Landfill at MCB Camp Pendleton, California. GCE performed an assessment of landfill liner that was bulging and leaking from groundwater intrusion on the flanks of the landfill and provided recommendations for repairs.

The task order objective was to provide the technical support services pertaining to the completion of a liner evaluation for Phase I of the Las Pulgas Landfill at MCB Camp Pendleton, California. GCE performed an assessment of the landfill liner that was bulging and leaking from groundwater intrusion on the flanks of the landfill.

Phase I Liner Evaluation – Initial Investigation

GCE conducted an evaluation of the Phase I liner at Las Pulgas Landfill to investigate the cause of the slope failure and bulging. The investigation was led by a California Civil Professional Engineer with specific expertise in solid waste landfills. Field work was conducted to determine components damaged, the cause of the failure, recommend remedies, and determine long term solutions to prevent further failures. The site was returned to the pre-evaluation conditions. A Work Plan and an Accident Prevention Plan, including Activity Hazard Analysis and Site Safety and Health Plan. were prepared.

A thorough document review was conducted to identify areas of concern in the design documents and/or construction documents related to the side slope areas of concern. A comprehensive review of the entire landfill design including base liner, waste placement, and cover system designs was excluded.

Laboratory testing on the low permeability soil layer (LPSL) included moisture contents, modified proctor, remolded triaxial shear, and permeability. No testing of subgrade soil was done as the LPSL was be assumed to be directly overlying bedrock.

Phase I Evaluation Tech Memorandum

A Technical Memorandum was prepared, which included a summary of all investigation work, characterization of the failure, assumptions regarding the possible cause, the remedy recommendations, short term and long term, to prevent future failures, and recommendations for further investigation.