|
Brunswick
Wood Preserving
Superfund Site TECHNICAL ASSISTANCE REPORT "This project has been
funded wholly or partly by the U.S. Environmental Protection Agency
under Assistance Agreement Number 1984482-98-0 Volume
1, Number 2
December, 1999
Feasibility Study Options |
Overview
The Environmental Protection Agency (EPA) has proposed several potential remedies for the Brunswick Wood Preserving Site (BWP) in Glynn County, Georgia. At this point, the Final Feasibility Study (FS) provided for review does not indicate the preferred remedy. There are at least two Operable Units (OU) expected for this site. The current FS deals only with OU-1.
BWP is a former wood treatment plant. Wood preservatives used oils, creosote mixtures, chromium, copper, arsenic and other materials. After the business failed the site was left with both organic and inorganic pollutants. The site continues to leach hazardous chemicals into the adjacent Burnett Creek. This Feasibility Study does not address offsite concerns or groundwater plumes known to exist at the site.
The Feasibility Study poorly defines Operable Unit 1 (OU-1). There are no charts clearly showing borders or delineating the areas of remediation for OU-1. There is only a vague description of the area around the Fiber Optics cable that crosses the site, and the Culvert Discharge area near Burnett Creek. According to the report, the model is not to be made until completion of a Baseline Ecological Risk Assessment. Consequently, all of the estimations provided for review are merely broad guesses, easily changed or ignored during Remedial Design. No Record of Decision (ROD) requirements would be enforceable given the site model provided in the FS.
OU-1 specifically deals with the topsoil and other soils to a depth no deeper than the water table. Since there is considerable standing water on this site, this definition is inadequate. Further, OU-1 incorporates a treatment cell, the CCA Soil Waste Cell (or CCA Cell), constructed by the Emergency Response and Removal Branch of the EPA. As far as can be determined, this is the only actual area designated for treatment. Groundwater cleanup is not included within this Plan, rather it is expected that groundwater plumes will dissipate (move offsite) after soil remediation.
More data and better plans are needed to fully define the remaining waste and any off site cleanup. Note, also, that the Human Baseline Risk Assessment guidelines used in formulating cleanup standards at BWP call for a commercial standard of 10-4 (one in ten-thousand probability of injury). This is the absolute minimum cleanup target allowable by law. A more thorough cleanup would encompass a residential cleanup of 10-6 (one in a million probability of injury) or, to say it differently, one hundred times cleaner.
Inorganic Pollutants
Inorganic pollutants are minerals, usually occurring as mineral salts, which cannot be further broken down and made safe. At this site the main inorganic pollutants are arsenic, chromium, copper and lead. These metal salts must be removed, immobilized, or diluted.
Organic Pollutants
The creosote pitch used to waterproof wood at the site contained Polycyclic Aromatic Hydrocarbons, or PAH, that is a mixture containing a number of toxic and carcinogenic components. The site also has high levels of pentachlorophenol, with associated levels of dioxin.
In contrast to inorganics, the organic material does break down in the environment. For organic chemicals, the environmental half-life or time it takes to reduce the danger by one-half, is an important consideration in choosing a remedy.
Remedy Selection Process
EPA has chosen no remedy at this time. However, U.S. Superfund law provides the selection criteria: cost, implementability, effectiveness, meets all relevant laws, state acceptance, and community acceptance. In practice, EPA generally only looks at cost, and implementability as a function of cost. There are instances where EPA ignores both relevant law and state and community wishes. Nor does EPA distinguish between short and long term effectiveness. Some cleanups designed to last a millennium have been termed failures after only a few years.
Implementability simply means whether or not the cleanup can be accomplished. Since EPA generally chooses relatively simple and low-tech processes, implementability is a minor matter. Cost considerations are usually EPAs main concern, not long-term effectiveness.
Proposed Remedies
CCA Cell OU-1 areas
An estimated 15,600 cubic yards of waste are contained in this cell. Five remedial options are described ranging from no action to offsite disposal:
|
Action |
Remedial Technology |
Process Option |
|
No action |
None |
Not Applicable |
|
Institutional Controls (A) |
Access and use restrictions |
Deed/Zoning restrictions; fencing |
|
Institutional Controls (B) |
Above, plus long-term monitoring |
Air, soil, groundwater testing |
|
Containment |
Capping |
All processes |
|
Removal |
Excavation |
All Processes |
|
Treatment |
Physical/Chemical |
Solidification/Stabilization |
|
Disposal (A) |
Onsite |
RCRA landfill |
|
Disposal (B) |
Offsite |
RCRA landfill |
CCA Cell (continued)
The current CCA cell is a short-term remediation option. The containment option would leave the pile in place and exchange the existing cover with layers of additional protection.
The best protection is offered by the RCRA designed landfill options either onsite or offsite. This provides for a fully lined cell that prohibits groundwater contamination. This is the most expensive option, so it is highly unlikely EPA will choose to envelope the waste and completely protect the site from further contamination. Solidification and stabilization of mobile organic waste is undesirable. Experience at other sites shows that stabilization is not effective at controlling discharge during treatment. Further, long term effectiveness is very dubious at best. Expect the remedy to be some variation of covering the existing pile with very little additional treatment, since this is the cheapest route.
IM-1 and Culvert OU-1 areas
Again, these areas are poorly defined at this time, so the recommendations here are speculations. A very rough estimate of the soil to be processed is 18,700 cubic yards. But, the formula for this calculation is mere guesswork. The following remedies are under consideration:
|
Action |
Remedial Technology |
Process Option |
|
No action |
None |
Not Applicable |
|
Institutional Controls (A) |
Access and use restrictions |
Deed/Zoning restrictions; fencing |
|
Institutional Controls (B) |
Above, plus long-term monitoring |
Air, soil, groundwater testing |
|
Containment |
Capping |
All processes |
|
Removal |
Excavation |
All Processes |
|
Treatment(A) |
Physical/Chemical |
Solidification/Stabilization |
|
Treatment(B) |
In situ |
Steam Stripping |
|
Treatment(C) |
Biological |
Solid Phase |
|
Treatment(D) |
Thermal(1) |
Desorption |
|
Treatment(E) |
Thermal(2) |
Incineration |
|
Disposal (A) |
Onsite |
RCRA landfill |
|
Disposal (B) |
Offsite |
RCRA landfill |
Biological remediation is appropriate only for the organic phases. No significant reduction of inorganic material is likely with these methods. However, the FS does not discuss in detail the methods considered for biological treatment or the areas that it may be applied. So, no value judgment can be made at this time on the effectiveness or applicability of biological methods. This is also true for incineration and thermal desorption. The FS is markedly nonspecific to be of value in assessing these technologies.
Solidification/stabilization has merit in small areas, however, the estimated 18,700 cubic yards of material seems spread over a very broad area and it is not clear how solidification could be applied.
Without clear descriptions of where the waste is, and where it may be treated on site, there is little merit to any of the proposed remediation options.
Conclusions
The Feasibly Study is excessively broad, thus not allowing comprehensive decisions on the final remedy. There appears to be little actual scientific data taken onto consideration, instead it relies on rough guesses. The actual extent of OU-1 is difficult to assess, given the vague description in the FS. OU-1 may be merely the CCA disposal cell, or it may encompass the entire site.
Remedy selection and a public meeting are inappropriate until completion and review of the Ecological Risk Assessment. No Record of Decision using these imprecise borders and site soil characterizations would be enforceable in a court of law.
Groundwater is a major issue, and should be a separate Operable Unit, studied concomitantly with OU-1. Biological treatment and incineration are generally inappropriate for inorganic wastes. Without charts showing that inorganic and organic wastes are separate or co-located, assessment of these technologies is difficult. Given the long time period this document was under development, it contains very little information of practical merit.
Written
by R. Kevin Pegg, Ph.D.; edited by Dr. Mary S. Saunders. Copies of the
newsletter are available from the GEC, at the Glynn County library, or at www.NucleicAssays.com/tags
on the Internet.