Source: http://www.marinij.com, November 2, 2016
By: Stephanie Weldy
Groundwater cleanup at Marinwood Plaza has stalled now that the state has rejected proposed plans to rid the shopping center of pollution left over from an old dry cleaning business.
The state Regional Water Quality Control Board last week rejected a study exploring potential groundwater cleanup approaches submitted by Geologica, a San Francisco-based environmental consulting firm hired by the property owner of the shopping center, Marinwood Plaza LLC. A representative of Marinwood Plaza LLC did not respond to a request for comment.
Cleanup methods suggested could take up to 30 years until effective, and are not aggressive enough, state officials said. The water board wants groundwater at the shopping center to meet drinking water standards within 10 years.
“The (water board) concluded that the proposed groundwater cleanup plan would take too long to reach cleanup levels given that nearby groundwater in the off-site area is already used for agricultural and domestic purposes,” Ralph Lambert, an engineering geologist for the water board, said in a written statement.
Geologica in the Sept. 1 proposal suggested natural attenuation of groundwater contaminants. A second proposal suggested injecting emulsified vegetable oil and zero valent iron at contaminated sites. The method could take up to 15 years to be effective. A third proposal calls for more aggressive injection, which could reduce cleanup time further.
Soil and groundwater in the area of Marinwood Plaza is contaminated with PCE, or tetrachloroethylene, from the former Prosperity Cleaners dry-cleaning business that once operated at the shopping center.
PCE was first discovered in the neighborhood in 2007.
Since then, the toxin has traveled off-site approximately 2,700 feet, according to the water board. It has made its way underneath Highway 101 and to the Silveira family ranch, east of the shopping center, and to property owned by Catholic Charities, where St. Vincent’s School for Boys is situated.
The shopping center, excluding the Marinwood Market, is set to be demolished so contaminated soil can be removed. The water board has ordered that soil at the center be excavated by early next year, with demolition of the plaza building required before excavation begins.
As for the groundwater, cleanup within 10 years is a reasonable goal, Supervisor Damon Connolly said.
“We’d obviously want it completed as soon as possible but we believe that would be more in line with what would be needed,” Connolly said.
David Trotter, an attorney representing the Silveira family, said “that’s probably about right if they did it the way they needed to.”
Cleanup activists are now calling on the water board to institute a firm deadline for a new plan.
“We thought when they rejected it, the one thing they didn’t do was to put a date to respond,” Marinwood resident Bill McNicholas said. “It was open. Marinwood Plaza LLC, they can respond whenever they feel like it.”
Michael Van Zandt, an attorney representing Catholic Charities, said he also was expecting to see a deadline.
Lambert said the water board does not want to restart the clock.
“We did not set a new deadline so the existing Sept. 1, 2016 deadline stands,” Lambert said. “We will consider enforcement action if an acceptable cleanup plan is not submitted soon.”