Highlights

General Comments

Comments on the 
Draft Feasibility
Study (FS)

Comments on the 
Draft Remedial
Investigation (RI)

References

Complete Report
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About Donna Boreck

Donna Boreck's 
Resume (PDF)

Technical Assistance
Grant (TAG)

General Comments on the Feasibility Study
 

PAGE	COMMENTS
2-39	Large Mass of PCBs in Fox River and Green Bay. Given the losses to the surrounding area either to Lake Michigan or through volatilization, the " PCB mass located between the DePere Dam and Chambers Island is so large, that, at these lower rates of loss, a large mass of PCBs will remain in these sediments far into the future"(2-39). It was also reported that the surface area for Green Bay is a significant volatilization pathway. Modeling results show that RAOs will not be reached given the time constraints and 500ppb and 1000 ppb action levels.  Because of human and ecological health, it is requested that the EPA reconsider removal of sediments to safe action levels from all reaches including Green Bay.
2-48	Time Trend Analyses. In the Executive Summary and other parts of the report, it is reported that sediment PCB levels and levels in fish are declining. The analysts record in a number of areas in Section 2.6 that there is uncertainty to the hypothesis. From the FS …"the river, its sediment, and its species may be experiencing an arrest or reversal of such a decline."  The text in the executive summary does not reflect the uncertainty noted by the analyst. The decrease in sediment levels are reportedly for the upper 4" of sediment. PCB levels below have not shown a trend toward decreasing PCB levels. In some cases, the trend is for increasing PCB levels in the subsurface sediments.  Sediments at 4" and below are susceptible to erosion, which would reverse the decline in the eroded area and allow for re-exposure of benthic organisms, fish, and wildlife to higher concentrations of PCBs.
5-1	Surface Weighted Average Concentrations rely on natural processes. From the report--cleanup to a higher concentration may be protective if natural processes can be relied upon to return sediment COC concentrations to protective levels in a reasonable time frame.  They are relying on sedimentation to bury or dilute PCB levels in sediments. Sedimentation is only one of several processes that is ongoing in both the river and the bay. Erosion, resuspension, bioturbation, disturbance by plant growth, human activity can all re-expose contaminated sediments to the water and species.  Relying on natural processes to bring the sediments to protective levels requires that the sediments support a concentration that is close to protective levels. In the Bay--where natural recovery is expected to handle the 1 ppm plus PCB levels--the difference between the 1ppm level and what is safe for aquatic species is significant. Natural recovery is not warranted for Green Bay and any other reach where the remaining levels are significantly above protective levels. A reasonable time frame--What is reasonable? Given the contamination levels, natural recovery may be a process that requires a century or more before protective levels are reached. In human terms, the time relates to five or six generations that will be adversely affected by PCB contamination.
5-6	PCB mass sensitive to action levels. They are proposing to base their removal on an action level -- maximize the weight and concentration of PCB to mass removed. In considering costs and available landfill space, this theory may seem valid. But the actual risk to humans and the environment seems to be lost in the calculations.  PCB removal is a protective issue. Although recovery to action levels may be considered proactive, there are a lot of ethical questions involving what remains and what it will do to both human and animal over time.  The method used to determine action levels and recovery of a mass parallels a time-honored method used by engineers to determine what will be extracted from the earth at what cost or given what equipment. The material handled often does not pose long term risk to humans and the environment. Here we are dealing with a man-made substance that is known to cause problems to man and the environment. At this time, it is affecting communities in-and-around Green Bay and the Lower Fox River. The principle of the FS should be to remove PCBs from the river and bay to a level that is protective --not remove what we want to remove and hope nature will take care of the rest.
6-6	Limited utility of MNR. On page 6-6, "…it (MNR) may have limited utility for the Fox River and Green Bay to be protective in a reasonable time frame because of : 1) limitations of natural dechlorination; 2) slow time trend decrease in PCB concentrations in fish and sediment; and 3) substantial fluctuations in sediment bed elevations that preclude long-term burial by cleaner sediment". MNR was retained for use only in combination with other methods. For Green Bay, MNR is being considered as the sole method for remediation. In the Appleton Capping proposal, MNR is being considered a main alternative for large reaches of river. Based on the comments in the FS, it is requested that MNR not be the sole or a major remediation alternative for either the Lower Fox River or Green Bay.
6-7	Dredging as an alternative. A review of case studies on dredging shows that dredging is the most tried-and-true method for PCB impacted sediment. Based on concerns of too-much-volume, dredging is being replaced by MNR, a method that is not proven to be protective of human and ecologic receptors at the level of contamination present in the Lower Fox River and Green Bay. Superfund requires Best Available Technology. In this case, dredging is proven and is the BAT.
6-10	Effectiveness of Institutional Controls. The effectiveness of institutional controls is only as good as the effectiveness of the communication and the willingness of the citizens involved to follow the advisories and restrictions. Language barriers and cultural issues can make implementing institutional controls difficult. As with MNR, institutional controls may not be as effective as we would like.
6-17	Uncertainty in the wLFRM model. It is noted that the model underpredicts the shear stresses and that higher erosional events may occur.  As the magnitude and temporal dynamics of settling and resuspension may be higher than modeled, uncertainty in the modeling needs to be taken into account in choosing technology and designing a remediation effort.
7-5	125-250 ppb Action Levels dropped from Green Bay. The action levels were dropped from consideration because "the large volumes of sediment precluded practical disposal options". The 250 ppm action level is still not considered protective for species.  It is requested that the decisionmakers reinstate, at least, the 250 ppm action level.
8-29	Higher Action Levels in Green Bay. As noted above, the lower action levels of 125 and 250 ppb were dropped from modeling and from consideration in Green Bay. At the 500 ppb or 1000 ppb, almost all of the RAOs were not met in the given time period. Under a complete technical analysis, it is important to include the 125 and 250 ppb action level to determine if the RAOs would be met at either of these action levels. Prematurely dropping the 125 and 250 action levels from analysis was inappropriate. Evaluation of only the 500 and 1000 ppb results does not give a complete data set to judge the effectiveness of different technologies. The decision was made to retain Green Bay for monitored natural recovery based on an incomplete analysis. It is requested that modeling be conducted at the 125 to 250 ppb level to complete the data set for review. Even without modeling, Green Bay, as a long term PCB source, needs to be remediated. It is requested that regulators reconsider the negative long-term impacts of leaving Green Bay PCB contaminated sediment to MNR.

Submitted 14 January 2002 
To Clean Water Action Council N E Wisconsin

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