Tag: Navy

Parkland and housing land coming soon from the Navy

Located between Alameda Point and Alameda Landing (where the new Target store has opened) is the Navy property known as North Housing.  After years of low-key planning efforts, the city will soon be the recipient of a beautiful new park, and eventually see over 400 new affordable and market rate housing units, including 90 Housing Authority units for formerly homeless individuals.

Estuary Park looking west. Past the trees in the distance is the baseball field.
Estuary Park looking west. Past the trees in the distance is the baseball field.

A key administrative milestone was reached in August of 2013 when the U.S. Department of Housing and Urban Development (HUD) signed off on the city’s plan to accommodate homeless individuals.

The 42-acre Navy parcel sits directly adjacent to Alameda Landing’s future residential neighborhood.  It includes the 8-acre Estuary Park where a baseball field, soccer field, basketball court, perimeter trail, and an open meadow flanked by mature trees await minor sprucing up by our city’s Recreation and Park Department.

Existing housing units to be demolished

The site currently contains 51 residential structures:  39 six-plexes and 12 four-plexes for a total of 282 three- and four-bedroom units.  All of the buildings were constructed in 1969.  With the possible exception of the two acres going to Habitat for Humanity, all of the units will be demolished to make way for new construction, according to the city’s Interim Community Development Director Debbie Potter. 

Central open space at North Housing. Looking north.
Central open space at North Housing. Looking north.

The 13 acres going to the city’s Housing Authority will have 90 units of new housing and two acres of open space.  Two acres will go to Habitat for Humanity.  The remaining 19 acres will be sold by the Navy to a private developer.

“The Reuse Plan notes the private housing developer could build 315 units,” said Potter.  After the Reuse Plan Amendment was prepared in 2008 and approved in 2009, the city certified a Housing Element in 2012 that rezoned this property to provide a Multi-Family Overlay zone, “so the number of units that could potentially be developed at this site is more than the 435 listed in the Plan,” Potter stated.   

One problem cited by Potter with trying to reuse the existing residences is that all of the multi-unit structures have single utility meters for the entire building.  To re-meter all the units with individual meters for electric, gas, and water would be expensive, according to Potter.

Typical North Housing multiplex military housing (vacant) constructed in 1969.
Typical North Housing multiplex military housing (vacant) constructed in 1969.

 “In addition,” said Potter, “the property is not laid out particularly efficiently, which is also a challenge.  North Housing has a multi-family overlay designation and it would be extremely difficult to take advantage of that zoning (30 units to the acre) with the current building layout,” she said.  “The only exception to all of this is that Habitat for Humanity East Bay has a Self-Help Housing Public Benefit Conveyance request pending with HUD which proposes an option of retaining 30-32 units to be renovated and sold as self-help housing.”

Housing Authority plays a key role

The Housing Authority will be partnering with the Alameda Point Collaborative and Building Futures with Women and Children who will provide services to residents of the Housing Authority’s 90 units.  A community center is planned.

Funding to build the Housing Authority’s homeless assistance units has not yet been identified.  However, Potter said she expects project financing would be packaged from a variety of sources, “with the primary funding coming from an award of Federal/State tax credits (equity raised through the sale of the tax credits to an investor),” she said.  “Other sources are most likely Federal HOME funds and dedicated housing authority funds the City receives as inclusionary housing in lieu fees and Affordable Housing fees paid by non-residential developers,” said Potter.

Alameda Housing Authority Director Mike Pucci has a good idea where the homeless housing will go, but is not ready to release a map.  “In our agreement that HUD has approved we did delineate a specific site comprising 13 acres, but a meets and bounds survey has yet to be conducted to establish it’s exact location,” said Pucci.

Checklist of regulations

The Navy completed its environmental review for the entire North Housing parcel in 2009 and issued a Finding of Suitability to Transfer (FOST) for Estuary Park.  A FOST for the housing area is awaiting decisions concerning Superfund cleanup issues early next year. 

The preparation of real estate transfer documents for just the park, however, could not proceed until HUD signed off on the city’s federally mandated homeless plan, according to the Navy’s Base Closure Manager Anthony Megliola.  “Now that HUD has made its determination, real estate documentation supporting the transfer is being prepared with transfer [of Estuary Park] planned in late 2013,” said Megliola. 

The remainder of the North Housing Parcel will be transferred in the 2015 timeframe, according to Megliola.   Factors include completing the cleanup actions for the benzene plume under part of the site, executing a Covenant to Restrict Use of Property (CRUP) with the California Department of Toxic Substances Control, executing a Finding of Suitability to Transfer (FOST) document, and preparing required real estate conveyance documentation associated with transfer.  “Although the National Environmental Policy Act (NEPA) Environmental Assessment (EA) was completed in 2009, receipt of the August 14, 2013 letter from the Department of Housing and Urban Development (HUD) was required before the Navy could complete the disposal actions for the North Housing area,” said Megliola.

Area where the Navy has been cleaning up benzene contamination at North Housing area.
Area where the Navy has been cleaning up benzene contamination at North Housing area.

Earlier in 2013, the Navy submitted a request to regulatory agencies to discontinue their vapor extraction work on the benzene plume hotspots, saying that vapor intrusion into buildings was not a risk.  The benzene vapor pumps were turned off in the spring and a new round of interior vapor tests were conducted in some of the existing buildings.  Results of these tests and a decision on whether to continue running the cleanup pumps for a few more years or terminate the program will be made in early 2014. 

This former military housing site was originally to be conveyed to the Coast Guard and was not part of the city’s No-Cost Economic Conveyance deal with the Navy.  (The new homes at North Housing will be in addition to the 1,425 units in the no-cost conveyance deal for Alameda Point.)  Subsequently, the Coast Guard withdrew its request.  In November 2007, the Navy notified the Alameda Reuse and Redevelopment Authority that it was going to declare an additional 42 acres of NAS Alameda – the North Housing parcel  – as surplus property.

As part of its requirements as the local reuse authority, the city had to comply with the McKinney Homeless Assistance Act and reach out to homeless housing providers for proposals.  In March of 2009, the city made its recommendations to HUD for compliance with the McKinney Act, approving the proposals from Habitat for Humanity, and the Alameda Housing Authority/Alameda Point Collaborative/Building Futures with Women and Children.  They also recommended the Alameda Recreation and Park Department proposal to receive Estuary Park.  These proposals became amendments to the 1996 Community Reuse Plan for Naval Air Station-Alameda.

North Housing area. Existing housing slated for demolition for create new, denser neighborhood.
North Housing area. Existing housing slated for demolition to create a new, denser neighborhood with public and private investment.
Estuary Park soccer field. Looking east. Alameda Landing and new Target store is past the tree line in the distance.
Estuary Park soccer field. Looking east. Alameda Landing is beyond the distant tree line.
Estuary Park baseball field. Looking east.
Estuary Park baseball field. Looking east.
Estuary Park fall foliage.
Estuary Park fall foliage.
This stormwater basin was constructed by Catellus to serve the Bayport neighborhood. It remains full year-round due to groundwater being continuously pumped from the special pumping station next to Shinsei Gardens. Overflow is sent to the Oakland Estuary via another pump station.
This stormwater basin was constructed by Catellus to serve the Bayport neighborhood. It remains full year-round due to groundwater being continuously pumped from the special pumping station next to Shinsei Gardens. Overflow is sent to the Oakland Estuary via another pump station.

Landscaping the Navy’s underground waste disposal site

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.
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.
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.
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

Navy could shut down groundwater treatment at housing site

The Navy often hears calls to increase its environmental cleanup effort.  Now, the community and regulators are hearing a call from the Navy to eliminate one cleanup effort altogether.

North Housing area next to Island High School where benzene plume is located.

Since 2009, several acres of the area north of Bayport that includes the Shinsei Gardens affordable housing development, former Coast Guard and military housing, the closed Island High School, and the Woodstock Child Development Center have been undergoing groundwater treatment to eliminate hot spots of benzene and naphthalene vapors.  Shinsei Gardens also included special building slab engineering in its design as an extra precaution against vapor intrusion.  The Navy now says that its groundwater treatment system is unnecessary and should be shut down.

Shinsei Gardens
Shinsei Gardens

In a report issued in December 2012, the Navy said the underground vapor extraction system called biosparging is not making the area any safer for human habitation.  Biosparging is a form of bioremediation that uses air and oxygen injections to stimulate the growth of naturally occurring bacteria, which break down toxics.  In this case, the contamination is composed of waste material discharged from an Oakland coal gasification plant and an Alameda oil refinery that operated long before the area was filled in.  The contamination layer has been dubbed the Marsh Crust.

OU-5 map with plume & landmarks

The Navy’s report points to the initial studies in the area that showed no risk from vapors.  The only justification for the remediation in the first place was the limited risk of contact with water through non-potable uses, since drinking water will always be supplied by East Bay Municipal Utility District. 

Now the Navy says that even non-potable uses are impractical and off the table due to high levels of minerals such as salt.  With no way of coming in contact with water containing benzene and naphthalene, the Navy decided to review the data for vapor exposure and concluded there is plenty of evidence to turn off the pumps.  The biosparge system was designed to run for eight years in order to reach its cleanup goals.

The Navy’s December 2012 Technical Memorandum is seeking to amend the original cleanup decision — known as the Record of Decision (ROD) — for this cleanup area.  They will need the concurrence of the regulatory agencies:  the regional Water Board, state Department of Toxic Substances Control (DTSC), and the Environmental Protection Agency (EPA).  But the EPA and DTSC are not ready to agree without further testing. 

According to EPA’s Chris Lichens, “The Navy’s conclusions are not based on current data, site conditions, or investigation methods.  Before proceeding with a ROD Amendment,” he said, “the agencies would like the Navy to collect additional data to verify that vapor intrusion would not present a significant risk in the absence of biosparging.”  Lichens added, “Along those lines, EPA and DTSC jointly prepared recommendations for additional groundwater, soil vapor, and indoor air sampling and provided those recommendations to the Navy.  The Navy has not yet agreed to collect additional data, although we are still discussing it with them,” he said.

Originally published in the Alameda Sun.

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.

Soil cleanup planned at runway workshops area

Future recreational open space

The 4.18-acre cleanup Site 34 in the old runway area next to the Oakland estuary looks barren from a distance.  But up close there are concrete slabs and pavement, reminders of its bygone days as a bustling workshop area.

This area was once part of the division known as the Naval Air Rework Facility (NARF).  Everything from sandblasting and painting, to metal working, woodworking, and scaffold maintenance went on out there. More than 40 years of activity left soil around buildings contaminated with lead, arsenic, pesticides, PCBs, and aircraft and diesel fuel.  Above ground fuel storage tanks and electrical transformers contributed to the contamination.

The Navy will clean up the soil in this area next year.  Their draft work plan, which will be released on July 31, was discussed during a Navy presentation at the July 2012 Restoration Advisory Board (RAB) meeting. 

Site 34 aerial view. Old fuel dock to left of site. Runway at bottom is part of area where antiques faire is held.  Navy photo/graphic.

Based on more than 200 soil samples taken in prior years and this year, the contractor created the draft work plan.  Separate groundwater samples indicate contamination from the solvent trichloroethane. No remedial action is being taken on the trichloroethane, however, because 1) vapor intrusion into residences is not a factor, as this land will become Public Trust Land on which housing is not permitted; and 2) water monitoring has shown that the chemical is not migrating toward the estuary.

The northern edge of this site is part of the early westward land extension of Alameda, which allowed trains carrying freight and passengers to get out to a point where the water was deep enough for ferry connections.  More fill was later added to the area.  According to the Navy’s Remedial Investigation report, “In the 1920s, most of IR Site 34 was filled with estuary dredging material during construction of the Posey Tube.” 

Site 34 starts at concrete slab on far side of tree. Port of Oakland on right.  In late 1800s and early 1900s, trains travelled on tracks along the estuary where tree and slab are.

By the time the closure of the Navy base was announced in 1993, this workshop area had 12 buildings, 7 aboveground storage tanks, 2 “generator accumulation points” (waste storage), 15 transformers, and over 7,000 feet of aviation fuel line.  Between 1996 and 2000 everything except the concrete pads and pavement was removed. 

Building demolitions ended shortly after Alameda Point became a Superfund site in July 1999.  The Superfund program, officially called the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), does not allow for land improvements such as building demolition.

Most of the soil cleanup locations are adjacent to the exterior edges of old building slabs. Much of the lead in the soil came from sandblasting lead-based paint.  Other contamination came from lubricants used for metals fabrications, and the use of oils and solvents for woodwork and metal work.  In addition to removing soil next to the slabs, the contractor will dig under the slabs at the hot spots to take what is called a sidewall sample to confirm that all contaminated soil is removed.  They have to keep digging as long as contamination is found. Clean soil will be brought in to the areas where soil is removed.

A strip of coastal marshland running along the Oakland Estuary on the north end of the site has no contamination.  Its habitat quality, however, is marred by discarded concrete, wood, and trash.  It will be up to the city to initiate wetlands restoration efforts there.

Coastal marsh on Oakland estuary at Alameda Point Site 34. Port of Oakland on left. Old runway area on right. Looking east toward Alameda Main Ferry Terminal.

A 60-day public comment period on the work plan begins when it’s released on July 31.  The work plan will be finalized in January 2013.  Fieldwork is anticipated to take place January through April 2013.

Site 34, located in the Northwest Territories, is expected to be given to the City of Alameda in 2014.

Click here > Site 34 RAB Presentation  for more details.

Announcing the new reference tab at the very top of this blog called “Cleanup document libraries.”

Scenic Alameda Point wildlife refuge section to be off limits with security fence

Alameda Point with the Port of Oakland on the left. Yellow outline shows Site 2 cleanup area. Green outline shows area where waste is buried. All but the wetlands in the bottom right corner of yellow area will be covered with clean soil. Fence and gates will be on landward sides of yellow border. Photo-graphic credit: US Navy.

Even after all the cleanup work is completed, the Navy proposes to put a permanent chainlink fence topped with barbared wire around a scenic shoreline section of the wildlife refuge at Alameda Point.

“Good grief!  If a fence is needed, will Site 2 be clean enough for our community?” Leora Feeney, co-chair of the Audubon Society’s Friends of the Alameda Wildlife Refuge, said upon first learning about the fence.   

The Navy used the site for underground waste disposal from 1956 to 1978.  According to representatives at the U.S. Environmental Protection Agency, the California Department of Toxic Substances Control, and the Regional Water Quality Control Board, the permanent fence has nothing to do with human health risks at the site.

According to the answer that the regulatory agencies provided collectively, “Potential human health exposure is unlikely to occur during recreational use on top of the soil cover such as walking or sitting.”  The soil cover will be seeded with native grasses.

The fencing is aimed at reducing maintenance costs for the new landowner, the U.S. Department of Veterans Affairs (VA).   “While the fence is not mandatory and recreational use without soil cover disturbance will not pose a risk to human health or the environment, the ongoing management of the protective cover in an area with public use without more direct supervision will increase risks and costs,” representatives from the agencies jointly stated.  

The VA’s annual expense for operating, maintaining, monitoring, and compliance reporting for the cleanup site, without added supervision, is pegged at $101,715, according to an advisory paragraph in the work plan.  ”There are numerous groundwater monitoring wellheads and landfill gas probes that require security to maintain monitoring integrity,” regulators stated. 

The Navy’s plans indicate that access to the shoreline trail will remain open.  But according to the regulators, “The perimeter road should have gates.  This concern will be clarified with the Navy.”

A view that will be off limits to the public if security fence is installed.
Photo by Eleanor Briccetti

The security fence, which will be inside the fenced off refuge area, departs from longstanding expectations for the refuge. Ironically, the off-limits wetlands area at this site is showcased on an Audubon Society brochure about the refuge.  Docent and ranger-led bird watching and nature walks have been part of the expected uses at the wildlife refuge since the mid-1990s.

By 1998, the US Fish & Wildlife Service had drafted its guiding document for creating the Alameda National Wildlife Refuge.  It envisioned supervised activity.  It was to be run in the same manner as other refuges, with controlled and monitored use, two law enforcement officers, and a cooperative agreement with the East Bay Regional Park District “to augment [Fish & Wildlife] Service efforts.”  Talks between the Fish & Wildlife Service and the Navy collapsed around 2004 over cleanup issues.

The shoreline restrictions imposed by the fence and gates are also at odds with the San Francisco Bay Plan, which is administered by the San Francisco Bay Conservation and Development Commission.  While permits are not required for federal projects, the official “Record of Decision” for this cleanup site states that plans will be in accord “with substantive provisions of the San Francisco Bay Plan.”  One of the keystones of the Bay Plan is maximum feasible shoreline public access.   “The city is discussing the provisions of remedial design for Site 2 with the Navy to support a future perimeter trail around the shoreline of the fed-to-fed parcel, which the city is strongly committed to,” said Jennifer Ott, Chief Operating Officer for Alameda Point.

Another of the Bay Plan’s guidelines avoids undesirable visual impacts on the shoreline.  One of the details in the work plan calls for 30 ten-foot tall, four-inch diameter, white PVC soil gas vent pipes for methane gas.  This array of pipes will be visible from the outside seating areas behind beverage purveyors on Monarch Street such as St. George Spirits.  “The city and Navy will discuss ways to minimize the visual impact of any new and/or replacement pipes, including the possibility of reducing their height,” Ott said.

Releasing methane into the environment has 21 times the greenhouse gas impact as burning it and turning it into carbon dioxide.  The city currently burns off the methane gas produced at the city’s old municipal dump, Mt. Trashmore.

Public comments on the draft Remedial Action Work Plan for Site 2 will be accepted by the Navy until Monday, July 9.  Responses to comments and a finalized plan will be announced in August.  A copy of the plan is available in the information repository in City Hall West, 950 West Mall Square at Alameda Point.  A rare opportunity to visit the site will take place on Saturday, June 23, when the Navy hosts the annual site tour.  To comment, or to sign up for the tour, contact the Navy’s Environmental Coordinator Derek Robinson at derek.j.robinson1@navy.mil.

 Site 2 details

The 110-acre cleanup site lies on the southwestern corner of Alameda Point within the 549-acre wildlife refuge, and includes 30 acres of wetlands and the 60-acre disposal area. 

Remedial work at the site is expected to commence in the fall of 2012 and be completed by summer 2013.  As a base layer for the soil cap, the Navy will use some 75,000 cubic yards of soil that it dredged from the Seaplane Lagoon and deemed clean enough for reuse.  The Navy will then barge between 400,000 and 600,00 cubic yards of clean soil from Decker Island in the Sacramento River near the town of Rio Vista.  The Navy says this will save at least 22,000 semi-truck trips.

The work plan document allays longstanding fears about underground toxic chemicals leaching into the Bay.  According to groundwater monitoring results in 2011, and comparing them to 16 years of data, all chemicals of concern are below risk levels and either stable or trending downward.  The plan includes the option of eliminating the groundwater monitoring wells in five years.

“Overall, the Navy believes that the soil cover remedy for IR Site 2 is directly compatible with the anticipated future reuse of the site.”

Navy, in Record of Decision, 2010

Seaplane Lagoon cleanup dredging completed [video and slideshow]

Dredging northwest corner of Seaplane Lagoon

Environmental cleanup of the Seaplane Lagoon has centered on two areas where storm sewers drain into the lagoon.  It was commonplace to discharge all sorts of chemicals down storm sewer lines prior to the passage of the federal Clean Water Act in the early 1970s.  Contaminants such as PCBs, cadmium, lead, pesticides, and radium have been found in the sediment around the sewer discharge points.

Prior to dredging, sewer lines leading to the northeast and northwest corners were either replaced or flushed out.  An underwater debris pile of metal and wood was also removed at the northeast corner before dredging.

The Northeast Corner

Setup for the 6.5-acre northeast dredging area began in late 2010, and dredging was completed in April of 2011.  The total amount of sediment removed was 75,628 cubic yards.  Even though the contamination depth was three feet, the dredging went to five feet.

Only 1,719 cubic yards of sediment were transported to hazardous waste disposal sites, of which 11 cubic yards went to a low-level radiological waste disposal site because of the radium-226.  The rest of the sediment was determined to be safe enough for reuse, in large part because the contaminants were diluted by the over-dredging of clean sediment.  The clean sediment has been stockpiled on the western end of the Wildlife Refuge for future use in capping the landfill disposal sites 1 and 2.

All of the drying pad materials for the northeast corner have been removed, which will allow for the fence to be moved.

The Northwest Corner

Concrete drying pad installed at northwest corner of Seaplane Lagoon

Setup for the 3.3-acre northwest corner began in October of 2011 with the construction of a concrete, waterproof drying pad.  Prior to dredging, a sunken barge was demolished and removed.  The barge pieces were scanned for radiation, but none was found.  The 66 tons of scrap iron was sent to a recycling facility.

Dredging started on January 16 and ended on February 22.  The dredging at the NW corner went much faster than the early dredging, partly because of the smaller area, and partly because of heftier dredging equipment.

Unlike the NE corner, however, the sediment here is expected to contain higher levels of radium-226 because the sewer line leading here was highly contaminated.  As was the case at the NE corner, this sediment will have to dry out before being tested and disposed of.  The project should be completed and everything removed by December.

The price tag for all of the Seaplane Lagoon dredging and hauling away sediment, when completed:  $46 million.

 

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