Aeration of Polluted Soils.
L A Wood, September 19, 1995
To: Berkeley City Council
The growing controversy surrounding Berkeley's Underground Storage Tank (UST) program reaches far beyond the obvious questions concerning the quality of air, water and soils. These polluted properties are posing a real health risk to our community. The old single-walled, constructed steel, underground storage tank have contributed to many a toxic spill in Berkeley. Most of these leaking, waste oil and gasoline tanks have been associated with automobile fueling stations.
Over the last century, Berkeley's fueling stations have been placed on nearly every corner of the city's commercial districts. Today, commercial districts are mixed use, including residential housing. The increased development of the city's commercial zones, coupled with the new UST regulations (1998), will create even more remediation activity in the future. Our current UST program is undergoing severe regulatory changes, and this is challenging the environmental health of our neighborhoods.
Contaminated soil and aeration
The State of California and the Regional Water Quality Control Board (Region 2) regulate the remediation of all Berkeley's polluted sites in conjunction with the city's Toxics Department. Each agency shares in the review of all site work plans for both soil and groundwater remediation. Historically, the aeration process is the most often approved treatment method of remediation, and this usually represents a sizable portion of the total cleanup plan.
Aeration is accomplished quite simply by spreading the contaminated soils across the site. This promotes the evaporation of the gasoline's volatile compounds into the atmosphere. Unfortunately, this transfer of pollutants from the soil unnecessarily contributes to the degradation of air quality. In South Bay, because of poor air quality, the Bay Area Air Quality Board restricts onsite aeration treatment. It is a convoluted logic, employed by this same board, which allows massive onsite aeration throughout the East Bay, supposedly because our air can afford to become dirtier.
These experts, who more often than not, rely on statistics and computer modeling to determine human health risks, are so far removed from the problem as to not understand the real impact of remediation upon the urban community. Typically, site plan analysis fails to acknowledge the actual urban setting and the residential nature of most of these contaminated properties..
Currently, Berkeley's aeration practices are poisoning our neighborhoods. The short term health effects are clear. Burning eyes and sore throat are but a few of the symptoms that one experiences with exposure to these toxic vapors. Such reactions are easily recognized as evidence of toxic exposure. The long term health effects to the many chemical components of gasoline have not been fully explored. However, the better understood chemical toxins, such as benzene, have been clearly linked to various cancer and respiratory diseases.
Diesel fuel, though common on many sites, is a perfect example of the lack of scientific data on health effects. For this reasons there is a tendency in the remediation process to dismiss those contaminants whose health effects are unknown. This often translates into scaled down site plans, reduced remediation standards, and the consequent negative impact on human health.
The effects of aeration on community health and the environment are undeniable. It is clearly seen in the practice of stockpiling soils on site for the express purpose of aeration. This dramatically increases the toxic exposure to adjacent neighborhoods. Many contaminated gas station sites are small lots, while the amount of soil to be aerated is great. Such physical logistics can often produce onsite stockpiles of soil, stacked as high as 20 feet. Contaminated soils can become airborne, presenting additional health risks.
Contaminant groundwater and aeration
Since most storage tanks were placed at a depth of at least 10 feet, many toxic leaks have impacted the groundwater, too. Ground water is the vehicle for migration of contaminants off site. This gradual movement of toxic spills is generally downstream, toward the San Francisco Bay. These spills are rarely stable. It's no surprise that Berkeley's records show many off site migration problems.
When a site remediation plan calls for the cleanup of large volumes of groundwater, onsite aeration is often the tank owner's choice. That choice of on site treatment can include the use of an open air Baker tank. The groundwater found on a site often contains the same contaminants which permeate the soil. These contaminants can be in higher concentrations in the ground water. The open air tank aeration of these toxins poses the same health and environmental concerns as soil aeration, and therefore, should be discouraged as well.
Health risk assessment and aeration
In the past, when a site cleanup plan included aeration, it was rarely questioned by the City of Berkeley. It was accepted as a normal practice. Today, however, these practices are beginning to change. Some onsite aeration plans are being required to develop a health risk assessment.
Though reports on risk assessments are occasionally performed, they usually are inadequate to protect the neighbors around these toxic sites. Such an example occurred last month at a toxic site on San Pablo Avenue. (See attachment) The next-door-neighbors to this former gasoline station were forced to flee their homes because the aeration activity filled their houses with gasoline fumes.
The Community Health Risk Assessment attempts to determine both chemical and physical exposure to remediation. With aeration, these components would seem to be indistinguishable. Risk reports rarely give more than token recognition to residents living near toxic sites. This has led to more health risk investigations concluding that aeration presents a low or moderate risk to the immediate community. It is unquestionable that aeration increases both the chemical and physical health risks to the community.
It should be noted that a site risk assessment report was required for the above mentioned San Pablo site. That document was challenged by. the city because of its statistics and the credentials of the health risk assessor. Unbelievably, the Regional Water Quality Control. Board approved the plan over the objections of Berkeley's Toxics Department. Today, the remediation process is being driven more by the cost , effectiveness of the clean up than how contaminant-free a site becomes. Aeration is the method most used to reduce remediation costs, other than a no-action scheme. The consequences are clear:
Berkeley's community and the local environment are left to shoulder the real costs of onsite aeration. This is due in part to the City of Berkeley's failure to mandate clear, sustainable remediation policies.. Some of the shortcomings of aeration which need to be addressed are:
• Alternative technologies: The reduction of airborne, volatile compounds is facilitated by the use of blo-venting with filtration. or catalytic burn off of the vapors after they are extracted from the soil. Both these approaches to urban remediation lessen the environmental impact of site cleanup activities.
• Incentive Programs: Currently the City can only approve or disapprove site treatment plans, and cannot tell them what methods to use. For this reason, it is imperative that Berkeley promote alternative technologies which increase protection to the community and environment. Incentive programs are an excellent way to promote these preferred methods of remediation.
• Weather windows: Aeration is influenced by weather conditions. Remediation should be discouraged on poor air quality days. When soils are left to aerate on site, they are purposely uncovered. This is a real problem during the rainy season because of polluted soils entering the storm drainage system. Currently, there are few weather restrictions governing aeration.
• Monitoring: There are many variables in the monitoring of on site aeration. Portable monitors provide limited measure and data. One way to provide better information is to require fixed monitoring in and around remediation projects, especially along any common borders with residential properties.
• Risk communication to public: The best way for the public to protect itself against aeriation pollution is to be better informed. The present notification process for residents around a remediation site is sketchy at best. Proper posting at each site should include an explanation of the project, the types of contaminants, health effects, work schedules, and contact numbers of the owner, the engineer, all onsite contractors, and all responsible reulatory agencies are all a part of the public right to know. This critical information is absent at most active remediation sites.
Sometimes risk communication is requested and sometimes it is required. Sometimes, however, the tank owner is given exemption by the Regional Water Quality Control Board from this reporting requirement. Unfortunately, neither the Board nor the remediation process encourage meaningful community participation.
Public notification of most remediation activities is delivered like a pizza flyer, stuffed in residents' doorways. A more formal notification process should be a requirement for every toxic site in Berkeley. Citizen participation needs to begin at the planning stage, long before the commencement of site remediation work.
Berkeley and aeration
The contradictions of onsite aeration are telling of the many problems fading our UST program. One month regulators will reprimand a tank site owner for not covering up stockpiles of soil, and the next month allow for a fullblown aeration plan! What are we doing? It is no wonder that our UST policies create so much confusion.
Berkeley's Underground Storage Tank program has seen few changes in the last twenty years. However, one exception is blatantly evident. Now more remediation plans are structured around cost effectiveness, with less attention being directed at the completeness of the clean up. This focus has limited the scope of many investigations and has resulted in more contaminants being left on site. Meanwhile, the list of stressed properties, which are either contaminated or adjacent to known toxic sites, continues to grow.
