Cleanup plan changes at waste burning area

Northwest tip of Alameda Point.  Waste burning area is immediately to the right of trees.  Port of Oakland is in background.
Northwest tip of Alameda Point. Waste burning area is immediately to the right of trees.  Port of Oakland is in background.

It was the 1950s, before the environmental movement of the 1970s and the laws that followed in its wake.  Hauling waste materials out to the western shoreline of Alameda Point to be burned and bulldozed into the Bay was not considered irresponsible.  The “Burn Area,” as it is called, lies next to the shore near the entrance to the Oakland Estuary.

Burn Area on Site 1.  San Francisco Bay to the left.  Oakland Estuary to the north.
Burn Area on Site 1. San Francisco Bay to the left. Oakland Estuary to the north.

By 2009, the Navy was ready with a plan to finally remove several acres of contaminated Burn Area soil and haul it away.  In 2010, testing by the cleanup contractor preparing to do the work, however, revealed additional burn residue that extends over a longer area and under the shoreline slope.  The new information triggered a complete re-evaluation of the plan.

Excavation and removal at the greater depth and under the shore would drive the cost up from the original $5 million to $40 million.  Fortunately for the Navy, a new and lower cost option became available just as the Navy and regulatory agencies were gathering more soil and groundwater data and discussing options.

In 2011, the US Army Corps of Engineers approved a shoreline steel containment system called an “open cell vertical confined disposal facility.”  Primarily used for harbor and waterway reinforcement and as a containment area for dredge sediment, the system is also suitable for permanently isolating and containing the toxic burn material along several hundred feet of Bay shoreline.  This option will cost $13 million.

Open cell sheet pile containment system under construction at Dutch Harbor, Alaska.  Photo source:  US Army Corps of Engineers 2011 report.
Open cell sheet pile containment system under construction at Dutch Harbor, Alaska.  The same system is proposed for the Alameda Point Burn Area.  Photo source: US Army Corps of Engineers 2011 report.

The Navy calls the open cell system a “waste isolation bulkhead.”  It consists of a wall of interlocked steel plates embedded in the earth along the shoreline.  Perpendicular steel walls extend toward the shoreline to form cells, or compartments, and provide anchorage.  The absence of welding to hold the system together allows it to flex without failing and eliminates the problem of welds corroding.

Tests around the Burn Area were conducted in 2010, 2011, and 2012 to determine if any of the chemicals in the burn residue were entering San Francisco Bay.  None were found to be entering the Bay.  Nevertheless, the Burn Area’s proximity to the Bay requires that it either be removed or permanently isolated.

The Burn Area is located on the 37-acre Site 1 cleanup area.  The site includes about a half dozen unlined underground pits that were used for waste disposal and are now partially covered by runway pavement.

Site 1 landfill map.  Area 1b is the Burn Area as it was originally configured.
Site 1 landfill map. Area 1b is the Burn Area as it was originally configured.  Click to enlarge.

Cleanup of a solvent plume on Site 1 that posed a potential threat to the Bay took place last year.  Previous cleanup on the site included removal of debris and soil contaminated by radium-226 used in painting luminescent aircraft dials.

When the Navy is finished with the Burn Area bulkhead barrier, the Burn Area will again be tested for radiological contamination.  All 37 acres of Site 1 will then be covered by at least two feet of clean soil and seeded with native grasses.

Site 1 will be available for passive recreational use as part of the proposed 147-acre regional park along the northern shoreline.  Site 1 will be part of the final conveyance of land to the city slated for 2019.  The VA’s property is adjacent and to the south and east.

The Navy’s project manager along with the cleanup contractor for Site 1 will be present at a special public meeting to answer questions and take comments on the new proposed plan for the Burn Area.  The meeting is on April 9 at the Alameda Main Library, 1550 Oak Street, from 6:30 pm to 8:00 pm.

Originally published in the Alameda Sun.

Further Reading on the Navy’s Burn Area Study

The Navy’s recently-completed soil and groundwater study for the Burn Area is called a Focused Feasibility Study (FFS) and is located on the state Envirostor website.

The FFS is very large and is divided into parts.  Recommended parts to look at first:

Part 1, Part 3 (cool maps), Part 4 (mostly raw data, but has trench photos), and Part 8 (descriptive letters from PND Engineers that own the patent on the open cell system, and all the comments by the regulatory agencies and the responses to comments.)  Part 5 has a lot of technical data and description of the groundwater model in relation to the Bay.

Reference material on the open cell barrier proposed for the Burn Area:

US Army Corps of Engineers 2011 report on the use of the Open Cell Sheet Pile Containment System for contaminated dredge material.

Overview of the Open Cell Confinement Disposal Facility system by PND Engineers.

2012 report to the Alaska Legislature on the Open Cell system.

Image highlights from the Focused Feasibility Study for the Site 1 Burn Area

Click on images to enlarge.

Ending threat of solvents in groundwater leaching into San Francisco Bay

Site 1 at the northwestern tip of Alameda Point was used as the principal disposal area for all waste generated at Naval Air Station-Alameda from 1943 to 1956.  This disposal area, which was once part of the Bay, was created by sinking pontoons and barges in the Bay and backfilling with dredge soil.

Disposal of cleaning solvents and petroleum products at one unlined pit within the landfill resulted in a groundwater plume that poses a threat of leaching into San Francisco Bay today.

In the 1990s the Navy installed an underground barrier system, called a funnel and gate permeable reactive barrier, to stem the flow of contaminants into the Bay.  It was not a permanent solution.  In July of this year the permanent solution began with the injection of neutralizing chemicals into the plume.

Protecting marine life

San Francisco Bay at Alameda Point western shoreline where threat of solvent leaching exists.

Most cleanup activities around the base are aimed at eliminating direct health risks to humans, such as from soil or from vapors that could enter a building.  In a few cases, the cleanup is focused first on direct impacts to marine life such as fish, which could in turn cause health problems for people who eat them.

The cleanup effort at the Site 1 plume is one of those cases.  This effort will keep toxins — solvents, petroleum products, and metals — from ever leaching into the Bay, being ingested by fish, and then consumed by humans.  The effort will also reduce unacceptable levels of vapors that are escaping directly above the plume.  The future use of the site will be restricted to open space recreational.

The process

July 2012 – Manifold system of hose lines that send oxidant chemicals to individual wells that go into the underground plume contamination area. Navy photo.

The chemical injection process, called In Situ Chemical Oxidation (ISCO), is accomplished by injecting oxidants (catalyzed hydrogen-peroxide and sodium persulfate) into the plume through injection wells.  “These oxidants produce short-lived reactions that directly destroy the targeted contaminants,” according to the Navy.  Groundwater tests will determine if further treatments are necessary.

Tanks of chemicals for neutralizing solvent plume. Shown as work area being set up in June 2012.

Treatments will continue until either the groundwater is clean enough, or the solvent and petroleum concentration has been reduced by 75%.  Once they get to 75% reduction, further injections are more or less a waste of money.  From then on, the contaminant concentration is low enough that the remainder will either degrade or disperse and dilute naturally without posing a risk to fish or humans.  This process is called natural attenuation and is often relied upon to finish the job when the bulk of contaminants are neutralized and treatment methods no longer yield effective results.

The groundwater plume is also contaminated with metals consisting of arsenic, copper, mercury, nickel, silver, and zinc.  The metals problem will, in theory, be taken care of when the solvents and petroleum products are eliminated.  This will cause the chemistry of the groundwater to change, which in turn will cause the metals to no longer remain dissolved in the water.  The metals will return to their solid state and remain where they are.  That’s the theory.

But to make sure it’s working, there will be a long-term groundwater monitoring program to make sure the metals aren’t moving.  If problems arise in the future, the Navy will have to come back and design a new remedy.  The Navy is responsible for the landfill’s contents staying in place in perpetuity.

Map of Site 1 disposal area with arrow from left indicating plume treatment area. Map also shows outlines of individual unlined pits that were used for disposal of waste. Half of the area is now covered by runway.

The Navy opted not to remove the landfill contents because of the $93 million price tag and because the risk of contaminant releases was deemed low.  A new set of environmental concerns associated with digging up and hauling away a landfill was also cited during the decision process.

The groundwater plume being treated is approximately 30 feet wide by 160 feet long, and it occurs mainly between depths of 5 and 10 feet below the ground surface.

Site 1 groundwater treatment work underway in July. San Francisco in background. Navy photo.

Delay on soil cover

All of 30-acre Site 1 will eventually be covered with soil and seeded with native grasses.  Work on the soil cover was delayed when the contractor discovered that the part of the landfill once used for burning waste was larger than expected.  The documentation has to go back through the review process, with a work plan for the soil cover hopefully prepared and ready to implement by 2014.

Where Alameda Point’s cleanup is at year’s end

 

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The past year had some high points and low points in the cleanup process at Alameda Point.  Added delays, including a pile-driving surprise, were balanced out by steady progress.

The year saw, among other things, completion of a second Point-wide radiological survey of buildings and structures that identified two building interiors needing radium remediation, a new soil scan for radium on a section of the western runway area, replacement of a storm drain segment next to the Seaplane Lagoon, and preparation of the environmental document for the Berkeley Lab site, which will be useful whether we get the Lab or not.

Northwest Territories - Site 1 dump area, partly covered by runway

The contractor preparing to cover the old dump with rocks and soil at the northwest tip of Alameda Point delivered some embarrassing news to the Navy.  In the normal course of their duties, work-plan design testing revealed that the shape of part of the contamination did not match the official description.  You would think they could just process a work-order change.  But the Superfund law requires an additional two-year review process, which will push the completion of this open space opportunity to 2015.

At another cleanup project, the Navy drove over four dozen 30-foot steel electrodes into the ground to heat up the toxins and capture the vapor.  But before turning on the electricity, the contractor discovered they had hit a sewer line.  The project has since been idle for months awaiting a decision on how to proceed.

Seaplane Lagoon dredge dewatering pad - northwest corner

The big Seaplane Lagoon dredging project that began in January is certainly one of the most dramatic displays of cleanup.  Both the northeast and northwest corners of the lagoon were supposed to have been dredged by April and final soil disposal completed by year’s end.  But the contractor failed to meet the deadline and was let go.  A new contractor has been testing and removing existing soil, as well as doing extensive set-up over the past two months for the dredging of the northwest corner that will begin in January.

Another dredging project has just begun under the dock area next to the maritime ships.  They’re removing mud contaminated from two storm drain lines.  That project is on schedule.  It’s worth visiting the area to get a glimpse of the elaborate engineering needed to capture and clean water runoff from the mud.

Shinsei Gardens low-income housing located above ongoing groundwater cleanup

Less dramatic and seldom seen work is always ongoing.  Groundwater is monitored at cleanup sites to ensure cleanup goals are being met.  One example is the monitoring of the removal of benzene and naphthalene under Shinsei Gardens and vicinity.

Evidence of the Petroleum Program is also seldom seen, other than some white PVC pipes in the ground.  But besides the big fuel extraction projects, there is ongoing testing of pipelines and oil/water separators in order to develop a remedial plan.

Finally, and perhaps most important, getting the first, very large, no-cost land conveyance from the Navy next year appears to be on schedule.  To help make it happen, the Navy and regulators are planning on modifying cleanup goals by enacting restrictions against future ground-floor residential development near the east entrance to Alameda Point.

Originally published in the Alameda Journal.

Case Study – Soil Cleanup Process at Island High/Woodstock Child Development Center

Island High School

A Case Study in How the Cleanup Process Works

In November of 2008, after years of testing, evaluation, and one emergency soil removal action, the Navy issued the final report on what to do in the area where Island High School and Woodstock Child Development Center are located.  The area is designated Installation Restoration (IR) Site 30. The Navy’s conclusion, or proposed plan, was that no further action is required.

The following description of the process is taken from the Navy’s 2008 report and proposed plan.  It serves as a case study in how the cleanup process is conducted with regard to soil. Highlighted terms are defined in the “Cleanup Glossary” located on the tab bar above. Continue reading “Case Study – Soil Cleanup Process at Island High/Woodstock Child Development Center”