Richard Bangert post stories and photos about environmental issues at Alameda Point on his blog Alameda Point Environmental Report.
Navy Stabilizing Point’s Shoreline
Navy Stabilizing Point’s Shoreline
The Navy made significant headway in June and July on its third and final soil-cover project at the Alameda Point. Trucks are hauling some 7,289 loads of soil from an East Bay Municipal Utility District soil-storage site in Castro Valley.
The frenzy of truck traffic through the Webster Tube and down Main Street have led to complaints of speeding trucks whose drivers are running red lights. These complaints have prompted the Navy to warn truck drivers that they could be removed from the job for violating traffic laws. Alameda Police Department has stepped up traffic enforcement in response.
San Francisco-bound ferry boat riders who board at the Main Street Terminal will notice a temporary mountain of approximately 200,000 cubic yards of stockpiled soil on the western end of Alameda Point. The Navy expects delivery of another 100,000 cubic yards of cover soil and 60,000 cubic yards of top soil for new vegetation by November. The Navy will use the soil to create a three-foot cover over the 60-acre cleanup site by the end of 2020. The Navy will turn this property over to the city for use as recreational open space once it has completed the $24 million environmental cleanup.
Some question the Navy’s choice of installing a soil cover to remediate for contamination since, technically speaking, the contaminants aren’t being cleaned up but covered up. An alternative method of cleanup that was considered but rejected would have dug out all the soil to a depth of 10 feet over the entire 60 acres and replaced it with clean soil at an estimated cost of $79 million, with a different set of environmental impacts.
In the case of the current 60-acre cleanup site, dubbed Site 32, the Navy and regulators considered a less expensive cleanup alternative that would have removed a dozen or so spots with contamination, mainly radium-226 luminescent paint waste. The reason for rejecting that alternative is that, despite more than 280,000 scanning data points being logged, radiation scanning is only accurate to a depth of one foot.
Thus, the spot-cleanup method would have left a lingering question mark as to what might lie a few inches deeper. Even though radium-226 poses a radiation health hazard only when ingested, and hiking and biking uses would not be expected to unearth bits of contamination, one foot of soil was not deemed a sufficient barrier. Out of an abundance of caution, the site will get a minimum of three feet of clean soil seeded with native vegetation, including a completely re-engineered and enhanced wetland.
Meanwhile, during the same time period, the Navy will also be embarking on a $5 million shoreline stabilization project along the edge of this soil cover and another adjacent soil cover that wraps around the tip of Alameda Point at the bay. Without reinforcement of the shoreline, the integrity of the soil covers could be at risk from storm surges, wave action, erosion and earthquakes.
The rock and masonry shoreline that is holding the land in place is old, with the section along the Estuary first constructed in the late 1800s by the U.S. Army Corps of Engineers. The shoreline stabilization project and its historical background will be covered in an upcoming story.