San Diego redevelopment officials, faced for more than two years with the perplexing problem of a lake of gasoline and diesel fuel under several blocks of valuable downtown land, have been told it will take possibly four years and at least $5.3 million to clean up the contamination.
The conclusion, contained in a consultant’s report released Wednesday and due to be discussed at a public hearing Nov. 18, represents the first time officials have been given detailed figures on how long and how much it will take to clean up the underground plume that now encompasses all or parts of nine blocks in the Marina area.
Officials of the Centre City Development Corp., the agency in charge of downtown redevelopment, have known for some time that it will take considerable effort and cost to extract the fuel. Another consultant had told the agency last year it was looking at a bill of more than $1 million.
The agency has already spent several hundred thousands dollars on constructing and operating a series of test wells and a pump station, including paying $225,000 to buy a 5,000-square-foot parcel on the southeastern corner of Island and 2nd avenues for the pump station.
The report by the consultant, International Technology Corp., says the agency will have to build essentially a combined two-level cleanup system. The main part of the system will remove free-floating gasoline and diesel fuel and place it in a 4,000-gallon underground tank. The other will take contaminated ground water brought up in the recovery process and cleanse it so it can be safely discharged into the sewer system, leaving the leftover fuel to be burned off in an incinerator.
Although such a recovery system will lead to the plume’s disappearance, it won’t do anything to clean either the remaining contaminated dirt or polluted ground water.
The consultant says that, based on current information for environmental agencies, cleaning the soil won’t be required to protect development in the area. It appears, the report said, that requiring new construction to build underground vapor liners should be an adequate form of protection.
Analysis of Projects
As for the remaining polluted ground water, the report says that the aquifer under the Marina area has been designated as not being beneficial, and therefore it is unlikely that the remaining ground water will have to be cleaned. But, the report notes, the designation could be changed. That would force CCDC to clean the water, adding substantially to the overall cost.
The system being recommended for San Diego, according to the report, is based on an analysis of projects at other locations, including El Cajon, Los Angeles, Santa Barbara, Malibu, Westminster and Calgary, Canada.
Based on that, the consultant believes it may take three to five years, but most likely four, to clean up the plume in San Diego. But, for budget purposes, the report said, CCDC should count on the recovery project lasting five years.
Depending on the number of wells constructed, the cost of installing the system in San Diego ranges from $1.4 million to $1.9 million. The annual operating cost ranges from $620,741 to slightly more than $700,000. The initial components of the system could be in place by next March.
All along, one of the stickiest problems facing CCDC has been who is going to pay for the cleanup. So far, the agency has grudgingly embarked on a course in which it will pay for the cleanup so as not to stop or slow development in the area, then attempt to assess the costs to property owners found liable for the pollution.
The problem is that at least part of the plume may have been there for 40 years and that responsible property owners may be hard to identify, let alone locate. CCDC is working with the state Regional Water Quality Control Board, which is attempting to identify the sources of the plume.
David Allsbrook, the CCDC staff member most closely involved with the plume situation, said Wednesday that the report will be presented to the CCDC board of directors this Friday, but that no discussion or presentation of its contents will occur until the Nov. 18 hearing.
“We want to be aboveboard with everyone on this,” he said. “There’s a lot of concern about liability and future recovery” of the cost.
Exacerbating the plume problem, according to CCDC, is the construction of the convention center, under progress nearby. Consultants have told the agency that the center’s massive dewatering system, which pumps about 1 millions gallons of water a day from the Harbor Drive site, is acting like a giant vacuum and pulling the plume closer to the bay.