West Beach Landfill – Alameda Point Environmental Report

Landscaping of the 100-acre landfill area on the southwest corner of Alameda Point is nearing completion. The seeding of the landfill site with flowering native grasses is almost ready to begin. Contouring of the site is complete. Stabilization of the shoulder around the wetland area is complete. Placement of the final soil cover is underway.

Site 2 wetland area and adjacent contouring underway in early July 2013. Wetland area has since been expanded by several acres. Port of Oakland is in the background. Bay Trail will eventually follow the foreground shoreline along the Bay. Funding and construction of the Bay Trail is not part of this project, and is yet to be funded.

The contouring of this industrial landfill site was completed on August 16, 2013. Approximately one-third of the contouring, or base layer, soil is clean soil recycled from Seaplane Lagoon dredging. The recycled soil stock was quickly exhausted, along with soil recycled after removing some of the berms and high areas. More than half of the base layer – 193,000 cubic yards – is soil barged in from Decker Island in the Sacramento River.

Soil being delivered from Decker Island.

This contouring phase, which began in January of 2013, created the base layer with a specially-engineered slope. It was then scanned for radiation using scanners towed by a small vehicle, even though the site had been surveyed for radiation prior to placing the base layer.

Placement of the plastic biobarrier (see photo below) and the final soil cover using soil barged in from Decker Island began on August 19, 2013. The biobarrier is a plastic mesh that is designed to discourage burrowing animals from coming into contact with the waste area. The biobarrier installation is over 90% complete as of week #38 (October 24, 2013). The final two-foot soil cover is over 60% complete. The final soil cover includes six inches of soil amended to promote growth of vegetation.

The soil stabilization and drainage work on the shoulder around the wetland area is also completed. It includes native rye grass seeding, a jute mesh cover, and a silt fence. Some of the rye grass has already started to sprout.

Stormwater controls near wetland area being created.

New monitoring wells will be installed starting in late November.

Hydroseeding of the site with an assortment of California native grasses will begin in late November or early December.

In 2014 the old culvert connecting the north side of the wetland with San Francisco Bay will be replaced with a new culvert.

Fifty tons of old fence and metal have been recycled. The temporary work fence will be removed at the end of the job. The methane gas vents will be short and virtually unnoticeable (see photo below). Due to the age of the landfill and the fact that very little organic waste was deposited there, the methane gas produced is minor and will not require the 10-foot tall vent stacks proposed in an earlier workplan.

This site, along with adjacent land, will be transferred to the U.S. Department of Veterans Affairs in late 2013 or early 2014.

VA map, with Site 2 and Nature Reserve notations added by Alameda Point Environmental Report.

Biobarrier to discourage burrowing animals. Photo credit: Alameda Point Environmental Report.

Silt fence installed above jute mesh around wetland area.

Jute mesh around wetland should, with grass starting to sprout. — Jute mesh around wetland shoulder, with grass starting to sprout.

Week 36 - Vegetation growing through jute mesh around shoulder of wetland area. — Week 36 – Vegetation growing through jute mesh around shoulder of wetland area.

Source: The information in this update was gathered from the weekly progress reports for Installation Restoration Site 2 Remedial Action at Alameda Point. The progress reports are posted on the Envirostor website maintained by the California Department of Toxic Substances Control (DTSC). The source for all photos in this update, unless otherwise credited, is DTSC.

Thirty-five years after the Navy stopped disposing of toxic waste in unlined pits next to San Francisco Bay on Alameda Point’s southwest shoreline, the final actions to comply with state and federal laws are finally being implemented this year.

Site 2 where industrial waste is buried. Area up to the wetland will be covered with two feet of additional soil.

Decades of wrangling between the Navy and regulatory agencies over how to handle the West Beach Landfill, dubbed Site 2, were finally ironed out this spring. The U.S. Environmental Protection Agency (EPA), the Regional Water Quality Control Board (Water Board), and the California Department of Toxic Substances Control (DTSC) have agreed to a plan that calls for leaving the estimated 1.6 million tons of industrial waste in place and adding more soil to the existing soil cover.

Placement of soil cover at Site 2 - May 2013. US Navy Photo. — Placement of soil cover at Site 2 – May 2013. US Navy Photo.

The Navy began dumping waste in the area in 1952, four years before they surrounded the area with a seawall. The dump was closed in 1978, but early efforts to comply with state environmental laws for landfill closure were not to the satisfaction of the Water Board.

In its May 2012 draft engineering work plan for the landfill, the Navy cited a decade of groundwater monitoring along the shoreline that proved the toxic chemicals of concern are not migrating toward the Bay. Instead, the chemical concentrations are either stable or declining. The contents have been sitting in water-saturated subsurface soil since the disposal program began 60 years ago.

Radiological hotspots of debris and soil, including a small storage building, were removed after an earlier scan of Site 2. Before the current two feet of clean soil is put in place, the soil will again be scanned down to a depth of one foot, and elevated concentrations will be removed. Radium-226 paint waste was disposed of in the landfill.

One of the major concerns about leaving this landfill in place is the consequence of a major earthquake. The Navy responded to a comment from a DTSC engineer by acknowledging that in the event of a maximum credible earthquake, the riprap boulders forming the “seawall is conservatively assumed to be non-existent, instantaneously whisked away and replaced with a 25-foot vertical face of liquefiable sand subject to plastic flow without being constrained by a rigid shell (sea wall).” The Navy’s earthquake model predicts that the earthen embankment above the seawall at the perimeter of the landfill, composed of clay and not sand, will glide into the Bay and “will not be overtopped by the waters of San Francisco Bay and freeboard of about 5 feet above mean sea level will remain, and so the refuse will remain isolated.”

Navy graphic showing predicted movement of embankment berm into San Francisco Bay during an earthquake. Click on image to enlarge.

Navy graphic depicting position of embankment berm at Bay shoreline a following catastrophic earthquake. — Navy graphic depicting position of embankment berm at Bay shoreline following a catastrophic earthquake. Click on image to enlarge.

Southwestern shoreline of Alameda Point at Site 2 landfill. Rock/cement riprap seawall, with green embankment berm above. Looking north toward Port of Oakland.

The Navy removed a perimeter security fence from their plans following objections from regulators and the public. “Navy’s design and [Superfund] requirements for this project do not preclude future use of the site for limited public access or passive recreational purposes,” said the Navy. Simple “Habitat Restoration Project” and “Stay on trail” signs were deemed adequate.

In an unusual move, the Navy offered the Restoration Advisory Board the opportunity to select the new vegetation that will anchor the 60 acres of clean soil. In the fall of 2013, the Navy will seed the new soil with 13 native grasses, most of them flowering. The Navy has permanently removed the 12-foot high embankment on the eastern, inland side of the landfill site, which will make the grassland visible from the mixed-use area.

The 30-acre wetland area on Site 2 was not contaminated, but will receive improvements to the quality of several acres. The culvert connecting the wetland to San Francisco Bay will be regularly inspected and permanently protected.

Final Remedial Action Work Plan for Site 2 – Alameda Point – April 2013