Detailed Comments on Major Project

Detailed Comments on Little Lake Butte des Morts

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Issues and Recommendations

• The Optimized Remedy represents a significant step backwards from the original ROD and leaves unacceptable amounts of PCB contaminated sediment (44-48% by volume of sediment) remaining in the Fox River

• Capping is not a viable alternative in the Fox River because environmental factors such as ice and flooding or groundwater seepage could compromise the integrity of any caps

• The management approach taken in the Optimized Remedy is more focused on logistical issues rather than managing and minimizing the risks posed by PCBs in the river

• WDNR needs to develop a source control plan for new and ongoing sources of PCBs into the river

• Investigations outlined in the BODR regarding loadings of PCBs are sparse and inadequate

• WDNR should develop a plan to achieve zero additional PCB discharges into the river

• WDNR should remove as much of the contaminated sediment within the Fox River as physically possible. The most effective method to reduce risks from PCBs in the river is to remove them

• PCB cleanup technologies such as sediment washing exist and should be considered as alternatives to the disposal of contaminated sediments in landfills or CDFs

Historical discharges into the Fox River have resulted in the accumulation of dangerous levels of polychlorinated biphenyl (PCBs) within the river’s sediments. This contamination has cascaded into and through the food chain to a point where fish in the river are no longer safe to eat. In 2003, a Record of Decision (ROD) was established mandating the need to clean PCBs from the sections of the river closest to where the river empties into Green Bay.

In 2004, the Fort James Operating Company and NCR Corporation signed an Administrative Order on Consent (AOC) with the Wisconsin Department of Natural Resources (WDNR) and the Environmental Protection Agency (EPA). The order required the two companies to design a cleanup plan that would meet the standards set forth in the ROD. Through a series of white papers a tentative plan was developed to dredge large portions of the river, and leave other portions of lower contamination sediments in place while monitoring them over time. Investigations characterizing the scope and nature of the contamination in the river have continued to this date. 

The Basis of Design Report (hereafter referred to as the BODR) presents the proposed preliminary remediation plans for the Lower Fox River developed by the Fort James Operating Company and NCR Corp. along with the data supporting them. This document forms the basis for the proposed changes to the ROD. While still relying on dredging in some places, the BODR differs significantly from the original ROD, primarily by substantially reducing the quantity of sediment that will be dredged from the river.

The new plan, referred to as the “Optimized Remedy” reduces the volume of dredged material through the use of capping in combination with sand and engineered caps. Some areas with low contamination will simply be capped, while some particularly deep deposits will be partially dredged before placing an armored cap overtop. Capping will occur over approximately 134 acres of the nearly 32 miles of river subject to cleanup under the ROD. The BODR claims that this will offer the same level of protection while requiring much less landfill space for the disposal of contaminated sediments and recommends the Optimized Remedy for this reason. 

ESC feels that this plan is a significant step backwards from the original ROD. The “Optimized Remedy” proposed in the BODR would remove 26% less sediment than what was originally planned for in the ROD. This change would result in anywhere from 44-48% of the PCB contaminated sediment remaining in the Fox River. Beyond the increased quantities of PCBs staying in the river, the Optimized Remedy recommends capping in areas that are not suitable for this alternative. Storm events, ice, and groundwater seepage could all compromise the caps and release the PCBs back into the river. The use of alternate treatment technologies such as sediment washing is recommended in place of capping and disposal of contaminated sediments in landfills.

Comments on the Optimized Remedy

The Optimized Remedy presented in the BODR does not provide the level of long term protection afforded by the original ROD remedy, and therefore cannot be recommended. The BODR frequently claims that “the bulk of PCBs will be removed under this remedy.” This is disingenuous, as only 62-66% of the total mass of PCBs will be removed under the plan. A more accurate statement would be “slightly more than half of the PCBs will be removed.”  The fact that this much contamination will remain in the river emphasizes that the Optimized Remedy takes the wrong approach to cleaning up the Fox River.

The reliance on capping and monitored natural attenuation to contain PCBs is based on weak assumptions and the basis for the rationale for their use is frequently contradicted by the data. While capping may provide adequate protection at some sites, it is far less suited for others. The key factor in a cap’s ability to adequately isolate contamination is the long term stability of the cap. Unfortunately, little to no long term monitoring of caps has been reported in peer reviewed literature.

For this reason, the combination of dredging and capping in certain areas of the Fox River is ill advised. The Optimized Remedy would leave the most contaminated sediments in place, increasing risks to human health and wildlife in the event of a cap failure. A cap cannot be guaranteed to be 100% effective over the long term (100+ years), making the safest solution the dredging of all contaminated sediments.

The reliance on capping is compounded by a reliance on monitored natural attenuation in upper reaches of the river. Natural Attenuation is simply a technical term for “doing nothing” and is unacceptable. PCBs can remain within sediment for up to 100 years or even longer, and no amount of monitoring increases the rate at which they degrade. Significant storm events could disturb otherwise stable sediments, transporting both sediment particles and their associated contamination downstream. Such events would jeopardize remediation efforts downstream, wasting valuable resources while putting both the public and wildlife at even greater risk. The risk is magnified even more by the fact that other contaminants besides PCBs are present in the Fox River. Mercury and dioxins and furans are all present in these sediments and will remain there for years to come.

There is no description given for any plan to achieve the Monitored Natural Attenuation called for in the BODR. The Optimized Remedy in Section 5.0 should have such a description, but there is no mention of natural attenuation in that Section. The BODR needs to give some justification and evidence that this strategy has any hope of succeeding. The ROD mentions natural attenuation, but gives no data demonstrating its effectiveness. Attenuation must result in real reduction in the concentration of the contaminant, not just burial or dilution. Attenuation should be the result of physical (sunlight), chemical (oxidation) or biological (bacterial decomposition) processes singly or in combination. Two of the more famous rivers on which no active remedial actions were taken are the James River, VA and the Hudson River, NY where chlordecone (trade name Kepone) and PCB’s, respectively, were spilled in the 1970’s. In neither case did the contaminants breakdown to the point of not being present in the river sediments after more than 30 years (see http://www.deq.virginia.gov/fishtissue/xls/2004kepone.xls for Kepone data; see http://www.EPA.gov/hudson for the Hudson R). 

While the BODR does not detail the spatial extent of contamination from heavy metals such as mercury, it acknowledges their presence. Metals do not degrade,  so natural attenuation is not possible. Decisions regarding the cleanup of individual contaminants in the Fox River should not be made in a vacuum with no consideration for other forms present. The presence of these metals emphasizes the need to dredge all contaminated sediments within the river.

Capping Limitations in the Fox River

Capping is not often an appropriate method to isolate PCB contaminated sediments from the water column. The physical integrity of the cap must be maintained over the life of the capped contaminants and any hazardous breakdown products. In the case of PCBs, this can be well over 100 years (Rice et al. 2003). The areas best suited for capping are those where the bathymetry is as flat as possible and tidal effects are limited (Palermo et al. 1998). The National Research Council (NRC) developed guidelines for site conditions that are favorable for the placement of caps (NRC 1997). Palermo et al. evaluated the 9 major capping criteria presented by the NRC in a white paper prepared for the EPA and WDNR (2002). 

ESC disagrees with two of Palermo’s conclusions regarding site conditions in the Fox River.

NRC guidance discourages the placement of caps in areas where there is ongoing contamination to the waterway. Palermo concludes that “external sources of PCB inflow have been controlled” (Palermo et al. 2002). However, the data strongly contradicts this claim. More information regarding this assumption is presented later in this document. 

NRC also suggests that capping only be used where “contaminants are of moderate to low toxicity and mobility.” At the time that Palermo’s white paper was published, the Optimized Remedy had not yet been proposed. Palermo noted that only non-TSCA eligible areas (less than 50 ppm PCBs) would be considered for capping, but under the Optimized Remedy, sediments overlaying high levels (300+ ppm PCBs)  of contamination would be dredged and then a cap placed over the sediments with the highest levels of contamination. 

PCB concentrations at these levels are extremely hazardous to human health and the environment, making these areas in the Fox River unsuitable for capping according to the NRC guidance.

One area of concern that Palermo notes is the NRC’s guidance that “hydraulic conditions will not compromise the cap.” Along with controlling ongoing sources, this is one of the most important factors to consider when determining if a cap is suitable for a site. Palermo notes that scour from flooding and ice could occur, and recommends armoring the caps and strict restrictions on where caps are placed. However, the data imply that the above suggestions may not be sufficient to insure cap integrity.

One of the most significant hurdles to the use of engineered or sand caps in the Fox River is the interaction between the river and surrounding aquifers. When caps are placed over areas where there is significant flow from aquifers into a river or other body of water where a cap has been placed, the pressure from the upwelling groundwater can place a significant amount of pressure on compressed cap materials, potentially compromising its integrity (Palermo et al 1998, NRC 2001). The BODR notes that such a phenomenon occurs within the Fox River, but fails to evaluate its effects beyond the displacement of porewater. These risks are in addition to other, weather related phenomenon.

One major weather-related threat to sediment caps in the Fox River is the formation of frazil ice and ice jams. The frazil ice occurs most often in turbulent, shallow waters at extreme temperatures (below 0° F) (Daly, 1994). The greatest threat from frazil ice occurs when the ice attaches itself to bottom sediments, after which it is classified as “anchor ice.” The formation of anchor ice not only facilitates increased scouring, but also encourages ice jams that have an even greater impact on the riverbed. Page 149 of the BODR notes that “…OU4 might experience scour of up to 3 feet under prevailing hydrodynamic conditions, and that there is a turbulent flow and potential frazil ice formation zone in the center portion of the channel extending immediately downstream of the De Pere Dam in which a greater degree of scour could occur” (Shaw, 2006). The extreme temperatures that cause the formation of frazil ice can occur any time between December and mid-March in Green Bay (NWS). While no water temperature data for the Fox River were available through USGS, data for the Namekagon River in Leonards, WI were available. The sampling station is at approximately the same latitude as the mouth of the Fox River. As shown in Figure 1, water temperatures hover around freezing from December to March. Therefore, it is theoretically possible for frazil ice and ice jams to form for nearly one third of the calendar year. Appendix D, Attachment D of the BODR is an estimation of the effect of such events on bottom sediments and cap integrity.

A review of the historical data shows that the analysis performed by Ashton on ice formation (2005) is cursory and incomplete. None of the conclusions are statistically verified, and fail to account for more extreme freezing events. The coldest temperature considered in the analysis is -5° F, while record lows of -20° and below have been recorded a number of times during the winter months. The analysis also does not investigate the effect of ice jams on additional ice formation in the areas behind the dam. It is unclear if such jams could result in ice impacting areas with caps.
 

Figure 1: Water Temperatures of the Namekagon River (US Geological Survey, 2006)

The danger of ice scouring or attaching to caps is illustrated clearly in Ashton’s white paper by the passage “Occasionally anchor ice has been known to entrain the sediment to which it is attached into the flow when the ice releases from the bottom. The writer has seen small-fist-sized rocks in floating ice covers that undoubtedly were the result of such a process but when seen, these have been widely dispersed and represent only insignificant transport.” What Ashton doesn’t note is that cap integrity is unrelated to the amount of sediment transported in this fashion. Fist sized holes in caps compromise both their ability to contain sediments and also the ability to resist future scouring events. 

Past experiences with caps have indicated that they are not suitable in rivers that experience even occasional ice jams, and that the ice itself does not always directly cause scouring. In 2001, a pilot study was initiated on the Grasse River to evaluate the use of capping to address PCB contamination in the waterway. After a particularly harsh winter, monitoring of the cap in the spring of 2003 indicated that significant scouring had occurred as a result of an ice jam that had formed over the cap (EPA, 2005) Modeling indicated and underwater videography confirmed that the scour was caused not by direct physical contact of the ice with sediment but from increased water velocity and turbulence just below the toe of the ice jam. The BODR does not appear to plan for such a contingency, further emphasizing that logistical and management related decisions have driven the creation of the Optimized Remedy rather than risk based goals.

Flooding is also a significant threat to caps in the Fox River. As shown in Figure 2, significant precipitation events and therefore discharges in the Fox River over the past 20 years occur mainly from May to September, with the greatest number of previous flash flood events recorded in June (NWS). The largest recorded discharge (33,800 cfs) recorded at the mouth of the river also occurred in June over sixteen years ago. Data were obtained from the USGS water database, which is available on the internet at http://waterdata.usgs.gov/nwis/sw. Attempting to determine average discharges at the mouth of the river from USGS data is difficult as the agency appears to only take data from this station sporadically.
 

Figure 2: Flash Flood Data for Green Bay, WI  (National Weather Service, 2006)

Data have been collected more regularly from a station in Wrightstown which has recorded 2 events approaching the 100 year flood estimate of 24,200 cfs used in the BODR (USGS). The station is located at the Rapid Croche Dam, which according to the USGS may influence discharges because of flow restrictions and other dam related activities. However, according to Figure 1-1 of the BODR this location is approximately 22 miles from the mouth of the river (Shaw, 2006). The two events in 1952 and 1960 had discharge rates of 24,000 and 23,600 cfs respectively. Locations downriver have experienced even greater discharges. One instance in 1990 caused a discharge of 33,800 cfs, and the same event caused a flow rate of over 46,000 cfs at the mouth of the East River as it flows into the Fox River (Baumgart, 2007, see attached figure). These high flow rates were caused by a combination of heavy rains and a powerful seiche. A seiche occurs when strong northwesterly winds build up water in the bay, which alters water levels and flow rates. The above data indicate that flood events of the calculated 100 year flood magnitude occur much more frequently than estimated, and wind can play a role in these events.

Other weather related events could have an indirect impact on caps within the Fox River. High wind events on waterways can lead to accidents or unplanned occurrences such as ships breaking their moorings and running aground in shallow areas. Institutional controls are of no use in these situations, so they must be planned for accordingly. Severe weather wind events occur primarily in the summer months, with a similar temporal distribution as flood events (Figure 3). While wind events are unlikely to have the same impact as flooding or ice formation/jams, they should still be considered when evaluating suitability of a site for a cap.
 

Figure 3: Frequency of Storm Related Wind Events in Green Bay, WI. (National Weather Service, 2006)

The above data indicates that caps in the Fox River have a high risk of being compromised by scour events 10 months out of the year. The potential for ice related scours is high though the winter months, and through the summer and early fall flood events become a significant concern. Placing a cap in such a high risk area is completely unacceptable. 

Changing conditions in and around the Fox River could also have an adverse effect on caps. Climate change will increase the occurrence of extreme weather events like those described above, but also including particularly low flows which could increase the chances of ice coming into contact with sediment. Population growth also would affect the river and any caps placed within it. The population of Northeast Wisconsin is expected to double in the next 25 years (Baumgart 2007). This would result in increased surface water runoff and higher river flows, along with the potential for higher non-point source PCB loadings. None of these future changes are addressed in the design of the cap presented in the BODR.

Cap Design

The ability of a cap to withstand impacts or pressure is tested through punch-through analysis. This is tested through theoretical modeling rather than actual field tests. The punch-through analysis for sand caps in the BODR only examines the pressure resulting from footsteps overtop the cap. This is unacceptable, as it fails to examine the possible effects of impacts from debris such as tree limbs during storm events. These objects would strike the cap with much more force than a human walking over it, and are much more likely sources of damage. If a cap could not withstand the force of a human stepping on it, then it would be completely useless, making this a ridiculous point of comparison. A more accurate one would be to model the impact of a large tree during a 100 year flood. The amount of force generated by such an event would be orders of magnitude more powerful that a footstep. It is vital that while evaluating remediation options, documented scenarios should be the benchmark for comparisons.

The analysis of stresses resulting from significant flow events does not use the more appropriate and conservative value available. Shaw estimated a 100-year flood event to have a maximum flow of 24,200 cf/s on page 162 of the BODR (Shaw 2006). However, on page 28 Table 2-4 states that the maximum flow recorded at the mouth of the river (where a significant portion of contaminated sediments lie) was 33,800 cf/s. While this value is assumed to come from a more significant event than a 100 year flood, that is no reason to remove it from analysis. The fact that this event has happened in recent history should make it clear that it could potentially happen again, and the remedy should be designed as if it will. It is unacceptable to discount data simply on the belief that it is a result of a rare event- such assumptions often have disastrous consequences.

One major problem with the Optimized Remedy is the degree to which it relies on spatial analysis to determine where dredging and capping will occur. While such analysis is important and done well in the BODR, it can never be done perfectly. “Hot spots” are an unavoidable reality in these sorts of cleanups and cannot be predicted accurately.

The cleanup process would be better served if WDNR simply dredged all contaminated sediments rather than attempting to guess where the areas of highest concentration are. The inability to accurately predict in all instances where more contaminated sediments lie is another example of the flaws in the dredge and cap approach presented in the optimized remedy. 

Alternative Sediment Treatment Technologies

The BODR does not have an adequate evaluation of alternative treatment technologies beyond thermal desorption. WDNR should consider all available treatment technologies, and landfilling or allowing the sediments to remain within the river should only be considered as absolute last resorts. The placement of highly contaminated sediments into landfills does not eliminate PCBs, but only isolates them until a time when the liner of the landfill fails or its contents are exposed.  The contamination surrounding Kidney Island is an excellent example of the pitfalls involved in contaminated sediment disposal.

Outlined below are discussions of various treatment technologies that have potential viability for this project and should be considered as alternatives to capping contaminated sediments or placing them in a landfill.

SEDIMENT WASHING

Sediment washing is quickly becoming one of the most viable options for treating contaminated soils and sediments. The process is relatively inexpensive (ranging from $40 to $200 per ton depending on a wide range of parameters), extraordinarily effective, and also produces a viable commercial product in the form of organically rich soil. The process has been proven at several sites, including pilot studies involving the treatment of sediments dredged from the NY/NJ Harbor. The process is relatively simple and produces a relatively minimal amount of harmful byproducts, all of which can be treated at a tertiary level POTW. This may be an issue in the Fox River, as Wisconsin does only requires secondary treatment at its POTWs.

The industry leader in this technology is Biogenesis Enterprises, a subsidiary of Weston Solutions Inc. The process that they have developed does not require a permanent facility and uses a minimal amount of equipment, including but not completely limited to: truck mounted washing unit, sediment processor, sediment washing unit, hydrocyclones, shaker screens, water treatment equipment, tanks, water blasters, compressors, and earth moving equipment. 

The process as described by Biogenesis (1999) begins by screening the sediment for large pieces of debris. After the sediment has been screened, it is then treated and mixed with chemicals to aid in the separation of contaminants and soil particles from one another. Soils are then run through a high pressure washer before entering an aeration tank. Foam at the top of the tank is continually skimmed to remove any floatable organics and then placed in a phase separator. Excess water is then pumped back into the process. The bulk of the sediment is then transferred into a high velocity collision chamber. Here the soil is subjected to an ultra-high pressure wash cycle that physically rips contaminants off of soil particles. From the collision chamber sediment is then transferred into a mixing tank where an oxidant (in most cases hydrogen peroxide) is added to wet sediment before being agitated in a cavitation chamber that aids in the breakdown of organics such as PCBs.  The sediment is then dewatered and is ready to be sold as organically rich soil. Soils that are still lightly contaminated but that still fall within cleanup standards may be used as backfill material or other non hazardous waste disposal options. Depending on the nature of the soil and cleanup levels required, this process may need to be repeated through one or two more cycles.

The Biogenesis process is geared much more to the treatment of PCBs than other pollutants such as dioxins and heavy metals. Cleanup rates of 99% for PCBs have been achieved in a pilot study examining various cleanup technologies in the NY/NJ Harbor area. Removal rates in the same study for heavy metals averaged around 90% while cleanup rates for dioxins achieved over 95% (Jones, et al, 2001). Other pilot studies have successfully cleaned a variety of contaminants to within cleanup standards (Amiran, 2001; DeDen, 2003). An additional study expected to be released in November conducted in the NY/NJ harbor is anticipated to show similar results, and the technology recommended to clean sediments in the Passaic River (C. Wilde, personal communication).

Factors influencing the effectiveness (and therefore cost) of sediment washing include sediment particle size, the level of contamination, and the amount of contamination to be removed. Smaller sediments are more difficult to treat because of their higher surface area to volume ratio. As the level of contamination decreases, so too does the effectiveness of the process. Like any sort of washing process, the efficiency of a rinse is inversely proportional to the amount of substance to be cleaned from the sediment. This does not mean that high cleanup standards cannot be easily met, only that higher cleanup levels require more washes and therefore higher costs. Other factors influencing costs are local market for the treated soil (which can be sold to reduce costs) and the amount of sediment to be washed (Biogenesis, 1999). In order to be cost efficient, a minimum of 10,000 cubic yards of sediment is required for treatment. Smaller volumes would not justify the costs of transporting and setting up the required equipment for the treatment (Wilde, 2004).

BIOREMEDIATION

Bioremediation can be defined as using naturally occurring processes to breakdown or otherwise detoxify contaminants. Most often this occurs in the presence of various species of bacteria, but other organisms such as higher plants can also be utilized. These processes all occur naturally over time, but the most efficient bioremediation projects in terms of both cost and level of cleanup optimize growth conditions (pH, temperature, etc) for the target organisms.

In addition to the optimization of growth conditions, primers or catalysts can also be used with effectiveness. Primers usually take the form of a compound easily broken down by the target organism which usually initiates dechlorination or other remedial reactions (Bedard, 1997). Catalysts such as certain species of iron or iron sulfide can also help initiate reactions (Zweirnick, 1998). These primers and catalysts are specific to the target organisms and the compounds that they are to detoxify.

Bioremediation has been successful in the treatment of a wide variety of chemicals ranging from PAHs to heavy metals. Considerable success has been noted in the dechlorination of contaminants such as PCBs and dioxins. Using bacteria such as Dehalococcoides ethenogenes that utilize chlorine for energy, high rates of dechlorination have been observed (Fennel, 2004). Rates increase substantially when a primer or catalyst is used. Zweirnick (1998) observed dechlorination rates of PCBs of 90%. The dechlorination of more complex compounds such as PCBs and dioxins generally is not complete (Zweirnick 1998, Fennel 2004, Bedard 1997). Usually the compounds are broken down into less toxic congeners such as ortho substituted PCBs (Zweirnick, 1998). While this reduction is still useful, persistent compounds with adverse health effects still remain after treatment. Some success in the complete breakdown of less complex compounds has been noted.  Pseudomonas stutzeri KC (strain KC) has been found to be highly successful in the dechlorination of carbon tetrachloride without the production of chloroform, the most common product of carbon tetrachloride degradation (Dybas, 2002). Heavy metals have also been successfully treated, but treatment is also dependant on specific contaminants. A study conducted by Seidel (2004) reduced levels of Zn, Cd, Mn, Co, and Ni by significant amounts, but the treatment had little or no effect on lead or chromium.

A significant obstacle to bioremediation beyond the compound specific nature treatments is the length of time that many treatments require. Less complex compounds such as vinyl chloride can be treated over the course of days (Bradley, 1996). However more complex compounds such as PCBs or dioxins have taken upwards of three years, and at a minimum of several months for most treatments (Gosh, 2000). 

Bioremediation could be difficult to implement within the Fox River, particularly given the massive scale on which it would have to be used. Potentially, bioremediation could be used in isolated areas of low contamination, but overall cannot be considered to be a viable treatment option on a broader scale. 

THERMAL TECHNOLOGIES

There are several technologies that use high temperatures to break down or otherwise destroy harmful contaminants. The main differences between the methods are the conditions that sediments are exposed to during the time that they are superheated. These differences affect the types of emissions and the efficiency of the processes.

All thermal processes except for vitrification have similar limitations. Most thermal processes can only treat organic compounds and mercury because of these compounds’ sensitivity to high temperatures. Other heavy metals are generally not removed from sediments, requiring further treatment. Fine grain sediments are also difficult to treat. The finer grains trap gasses between the soil particles, making the thermal processes less efficient. Thermal processes also require thorough pretreatment in the form of dewatering. 

Incineration is the most common type of thermal treatment and is used for a wide variety of wastes ranging from medical supplies to sediments (Eche, 2001). Incineration is also the most basic type of thermal treatment, where sediments are exposed to temperatures in excess of 700º C, breaking down most organic compounds and volatilizing mercury. Facilities are permanent and can occupy one to two acres of land. The process is not effective for PCBs due to the reaction forming dioxins that those compounds undergo when burned (Jones, 2001). Dioxins are one of the most dangerous classes of compounds because they share the persistent nature of PCBs and are more toxic. Scrubbers are used to reduce harmful emissions but are not effective enough to remove all emissions and in fact most incinerators do not meet air emission standards. Costs are typically high, ranging from $500 to $1350 (Sierra Club, 2001) per cubic yard because of the high energy costs.

Thermal desorption is similar to incineration but uses an additional scrubbing system to treat gas emissions. In addition, the heating process is performed in the absence of any oxygen and thereby removing the possibility of any dioxins or furans from being produced. Gas emissions are trapped and condensed with water, creating a contaminated but more easily treated waste stream. Facilities are designed to be portable but still may take 2-4 months to set up depending on the size of the project (Chemical Waste Management, 1993). Thermal desorption has been successfully demonstrated in pilot studies at a PCB contaminated Superfund site in New York (Jones, 2001). Costs are much lower than other thermal technologies, ranging from $55 to $150 per cubic yard (Sierra Club, 2001). However, true treatment costs will be higher than this because of the need to treat the contaminated waste stream created by the process.

Thermal reduction systems use the same processes of thermal desorption but treat the gasses differently. Instead of simply condensing the contaminants with water for later treatment, thermal reduction injects hydrogen into the process and chemically reduces organic compounds into less toxic forms. Air emissions are recycled back into the process to increase the efficiency of contaminant reduction. Overall efficiency is dependant on the initial thermal desorption phase because this is where contaminants are physically released from the sediments (Smith, 2001). The technology is considered transportable but not necessarily portable, meaning that set up times are generally quite long (6-12 months) and difficult to set up. Costs are much higher than thermal desorption, ranging from $225 to $525 per cubic yard (Sierra Club, 2001).

Vitrification is the only thermal treatment that can treat metals other than mercury and also does not have the same problems with fine grain sediments as other thermal treatments. The process is similar to incineration, using even higher temperatures (> 900º C) temperatures to volatilize mercury and destroy organic compounds (Tzeng, 2000). The higher temperatures melt the sediments and remaining metals into a slag which is later hardened, effectively binding the metals and stabilizing them in a compound that can be resold as bricks, gravel, or other construction supplies. Air emissions are scrubbed in similar fashion to incineration, and because of the similarities between the processes the same potential exists for the creation of dioxins and furans. Facilities are difficult to set up and can take 6-12 months for site approval, depending on the size of the project. Costs are greatly reduced by the creation of an end product that can be easily sold. As a result costs are significantly lower than incineration, only running $60-90 per cubic yard (Sierra Club, 2001).

Thermal technologies are effective at eliminating contaminants such as PCBs from river sediments. However, the primary drawback of these technologies (the creation and release of dioxins and dioxin-like compounds) counters the overall benefits from their use. Creating one toxin to eliminate another is not acceptable, particularly given the particularly toxic effects of dioxins even at low concentrations. For this reason thermal technologies are not recommended to remediate contaminated sediments from the Fox River.

IN-SITU CAPPING TREATMENTS: ACTIVATED CARBON STABILIZATION

Another more recent method to remediate sediments that are contaminated with organic compounds such as PCB’s uses materials that bind or react with the chemical or the sediment particles. Several research papers examine the effectiveness of activated carbon in immobilizing PCB’s in sediments (Ghosh et al., 2000; Zimmerman et al., 2004). The basic concept is to bind the contaminants to the activated carbon and thereby reduce the ability or propensity for the contaminants to move from particles to either water or tissues of infaunal animals.

The work of Gosh et al (2000) and Zimmerman et al (2004) indicate a reduction of up to 99.5% in the water concentrations of PCB’s following treatment with activated carbon. The method involved mixing the contaminated sediments with activated carbon at a concentration of 2.5 % activated carbon. This method was used in both lab and field trials. The results were consistent in showing reductions.

Follow-up research showed that activated carbon also reduced uptake of PCB’s from contaminated sediments by clams and micro-crustaceans (McLeod et al., 2004; Millward et al., 2005). The >90% reductions in uptake could be from direct sediment uptake or pore-water uptake. 

This method has some promise but has not been tried and used in long term field conditions. Even if lab or field trials of days to months duration are effective, the long term effectiveness remains unknown. Several factors must be evaluated in assessing this method, such as the stability of the contaminant-carbon association, integrity of the carbon over long periods, and the resistance to biological activity (microbial, macroinvertebrates, etc.) over decadal periods.

Treatment Recommendations

Because of its effectiveness in eliminating contamination and the ability to reuse soil after treatment, the Biogenesis sediment washing process is recommended as a means to reduce the volume of contaminated sediment designated for landfilling. Treating contaminated sediments is far preferable to capping or landfill disposal as it actually eliminates PCBs instead of risking future exposures either through seepage from landfills or the failure of a cap. Bioremediation has yet to be proven cost effective and thermal technologies such as vitrification create harmful byproducts such as dioxins and distribute them over wide areas through air emissions. Currently, sediment washing appears to be the most cost effective and safest treatment option for contaminated sediments. It has a proven track record in treating the contaminants of the Fox River and satisfied the EPA’s recommendations for the beneficial use of treated sediment. 

Control of Ongoing PCB Sources

The Fox River receives effluent discharges from a number of industrial and municipal facilities for some distance. According to EPA (EPA 1998), at least 14 major dischargers have been identified as sources of PCBs and list PCBs in the facility effluents. These dischargers are listed below. The Wisconsin Department of Natural Resources (WDNR 1999) has identified thirty-three dischargers, including those listed by the EPA, as facilities which have included PCBs as being discharged between 1973 and 1997. These dischargers are listed below. Further information on these sites can be found in Appendix A. 

Major discharge sources of PCBs into the Fox River (US EPA 1998):

• Kimberly Clark-Badger Globe Combined Treatment Plant
• P. H. Glatfelter-Bergstrom Division
• Kimberly Clark-Lakeview Division
• Neenah Menasha Combined POTW
• Wisconsin Tissue Mills
• Riverside-Kerwin Division
• Consolidated Papers-Appleton
• Appleton POTW
• Thilmany Paper
• DePere POTW
• Fort Howard
• James River/American Can
• Green Bay Packing
• Green Bay POTW

The river is a major sink for PCB’s from historical discharges and from both current ongoing discharges. The goal of the cleanup effort is to improve the quality of the river environment for the protection of human and ecological health, and without strict control of PCB sources water quality improvements will be minimal regardless of the success of any dredging or capping program. WDNR identified 33 separate facilities discharging into the Fox River, 9 of which are paper mill facilities that have been identified as the most significant sources of PCBs into the river. (WDNR 1999, Shaw 2006). 

The BODR considers these sources to be insignificant; however such assumptions cannot be made without adequate evidence. Stormwater data is the only evidence cited in defense of this assertion within the BODR, and it is significantly flawed. Stormwater was only tested during significant rain events, which are likely to dilute concentrations from those sources to non-detectable levels. Under normal conditions with small scale periodic rains these could in fact be a significant source. The BODR estimates that point sources could account for as much as 23.5 kg/yr. This value is only insignificant in comparison to the massive loadings released from sediments. The goals set in the ROD cannot be met with continuing point source discharges of this magnitude. In order to meet these goals, WDNR needs to act decisively to control these sources.

As soon as possible, WDNR should develop a plan to achieve zero PCB discharges into the Fox River. Such an action is likely to encounter stiff resistance from dischargers, but this is no excuse to not meet the obligations established in the ROD. Only once these sources are controlled can long term remediation of the Fox River be successful.

Specific Comments on the BODR

Section 1

This section is primarily background information on the Fox River, and as such we have no comments on this portion of the BODR.

Section 2

Section 2 outlines the basic characteristics, both physical and chemical, of the Lower Fox River and the sampling programs performed to generate the data.

Section 2.2

Section 2.2 describes the physical characteristics of the Fox River. It should include a discussion of the organic content within the sediment as this has direct implications for the remediation of PCBs because of the affinity these compounds have for sediments with high organic content.

Section 2.2.2.4

This section details the infrastructure, utilities, and obstructions in the waterway which may influence the cleanup. On page 24, the fifth bullet for OU4 notes that archeological sites are present. What is the nature of these sites? This needs to be expanded on.

Section 2.2.4

Here hydraulic characteristics such as groundwater and discharge rates for the Fox River are discussed. In addition to the table on page 27, there should be a figure included in the document to display the historical flow data for OU2 from 1917-present.

Section 2.4

This section emphasizes the overall management position that disposal options and costs will drive the cleanup process. The emphasis should instead be on meeting water quality goals in terms of fishable and swimable waters.

Section 2.4.2

This section outlines the methodology by which sediments are identified for disposal in a TSCA landfill. Why is OU4 the only area considered in this section? Other areas throughout the river have been recorded at or near these levels. This has serious implications for the disposal of contaminated sediments.

Section 2.5.2, Best Management Practices, pages 50-51

Best management practices (BMPs) should include the use of silt curtains, specific “no-dredge” weather and river conditions, the use of environmental buckets for the highest concentrations of PCBs, and other operational controls.

Section 2.5.3.2

The methods used to estimate PCB loadings from tributaries and urban runoff in this section are very crude and likely underestimate the amount of PCBs entering the river from these sources. Even with these flaws, these estimates indicate that stormwater sources contribute a significant amount of PCBs to the river and need to be controlled if water quality goals are to be met.

Section 2.5.3.3

The last line of this section discussing atmospheric loads should be changed to indicate that atmospheric loads are only negligible when volatilization is factored into the mass balance.

Section 2.5.3.4

On what basis is the assumption made that there are no loadings from surface water runoff at the Arrowhead Park Landfill? Without data, this assumption should not be made, particularly given the fact that the landfill is a documented source of PCBs into the groundwater.

Section 3

This section discusses the original remedy selected in the ROD, and outlines site considerations, dredging volumes, and the disposal of dredged sediment.

Section 3.1.1

When determining considerations for the transport of dredged materials, the document again is proposing management decisions that are based on logistical issues rather than cleanup goals. This approach is backwards. Cleanup decisions should be made based on the stated water quality goals, and logistical issues should be approached with achieving them.

Section 3.2.1

This section noting the equipment selection process should make the environmental bucket dredge the default equipment for mechanical dredging.

Section 3.3.2.2, page 71, second full paragraph

This section notes that one section where PCB concentrations run between 70-80 ppm that cannot be dredged. Sediments with this level of contamination should be removed, even if engineering controls are needed. If these areas cannot be cleaned up, signs and other institutional controls should be required. 

This paragraph also notes that “sediment caps constructed in this side slope area will be designed to ensure permanent protection.” If caps are used, then all should be designed as such.

Section 3.3.4

When designing the dredge prism or the three dimensional volume of sediment to be dredged, efforts should be made to insure that the result is as protective to human health as possible. To be conservative and protect these resources, Type II (identifying contamination in places where it doesn’t exist) errors should be preferred to Type I errors (determining that no contamination is present when it actually is) that to overcome uncertainties associated with dredging, the opposite of which is proposed in the BODR.

Section 3.6.3.5, page 89, Metals

This paragraph is a gross misrepresentation of the metal concentrations shown in Table 3-9. While dissolved concentrations of metals did not exceed standards, total concentrations of mercury were well above standards. This paragraph should be amended.

Section 4

This section is a continuation of the issues outlined in Section 3. Section 4 focuses specifically on sediment transport and disposal.

Section 4.1.1, page 111, first full paragraph

This paragraph notes that amendments to the percent solids in landfilled sediments may be required to reduce costs. What are the costs of the amendments not included? The inclusion of even rough estimates would be helpful.

Section 4.1.2.4

This section notes that treated decant water will be discharged directly into the Fox River. This water should be tested before it is allowed back into the river to insure that it is not damaging to water quality.

Section 4.1.2.5

Tested leachate from the Fox River contained significant concentrations of lead, arsenic, and PCBs. These compounds should not be allowed to enter groundwater. There should be no such discharges without treating the water first.

Section 4.3.7, page 132, first paragraph

Sand from the Fox River should not be used in conjunction with WWTP biosolids and sold as topsoil. These biosolids often have significant levels of PCBs, dioxin, and heavy metals. Combining them with even lightly contaminated sediments from the Fox River could create a significant health threat.

Section 4.3.8

The BODR proposes that dredged sediments from the Fox River be placed in the Renard Island CDF. However, it is clear that the island is already a hazard and not constructed adequately to contain contaminants.  Additional contaminated sediments would only add insult to injury, and increase future costs of remediation at Renard Isle. No additional sediments should be placed at this facility.

Section 4.3.12

The BODR proposes that lightly contaminated dredge material be used to cap more contaminated sediments in other areas of the river. This potential use of dredged sediments is completely unacceptable. Taking even marginally contaminated sand and using it as a cap over other contaminated sediments defeats the purpose of a cap. These sediments should be disposed of or treated as contaminated.

Section 5 Optimized Remedy

The introduction to this section outlining the Optimized Remedy states that substantial new information has been obtained and that much of the PCB contamination will still be removed. This section also claims that the capping will achieve the same level of protection as the ROD. The problem here is that the text does not explain the amount of PCB’s that will be left in the river, the general uncertainty of how the caps will function, the overall comment that substantial Institutional Controls will be required essentially forever on this section of the river or that the primary purpose of the change from the ROD is to save money for the responsible parties.

This introductory section needs to be clear about the unknowns and gaps in this cleanup plan. The introduction should give a general statement regarding levels of uncertainty, the weather conditions in the river that raise problems for capping, the residual risks that can be expected and other uncertainties and unknowns. This section should also state that the ROD and BODR only have limited information on ongoing sources and the estimate from WDNR is that the current discharges will continue adding PCB’s to the Lower Fox River for many decades.

The BODR states in numerous places that the 6 inch layer of sediment is too thin to effectively dredge with a hydraulic dredge without capturing clean sediments that underlie the contaminated sediments. The problem here is that the BODR presents no data which supports this claim regarding the inability of dredge equipment. If this statement is to be believed, then the BODR must provide documentation that some project attempted dredging 6 inches and failed or letters from dredging operators and contractors, or any other hard data on which to base such an important decision. 

The situation is in fact worse because of the other assumptions regarding a thin, 6 inch sand cap on 210 acres of the river where sediment PCB is 1-2 ppm. The BODR assumes that the surface sediment mixes with the lowest layers of the sand cap, essentially causing the two layers to form a boundary layer of sorts. The BODR assumes this mixed layer is 3 inches. The top 3 inches is then the thickness of the clean sand that forms the cap to separate the contamination from the river water and anything else.  The punch through analysis is based on 6 inches, not 3. The result would then be that a person walking on the sand (the punch through scenario) would or could penetrate the sand cap to a depth greater than 3 inches, and reach the “mixed” layer where the contamination is assumed to begin. 

The punch through analysis does not account for objects falling into the river and being driven into the sand cap with any force. The punch through analysis needs to account for tree limbs, objects falling from ships, docks and shoreline, and other situations in which projectile penetration is evaluated. The BODR authors surely recognize that large objects fall into the water and can penetrate into the sediment or be driven into the sediment by the force of floodwaters or river ice.

The BODR does not mention and therefore must discount recreational boat use of the river. Boaters anchor and anchors can and do penetrate more than just an inch or two into the sediment. Anchoring will certainly increase physical disturbance of the sand caps.

The BODR does not present a failure analysis or accident analysis for the extensive capping of high and low level contaminated sediments in the river. The BODR should, at a minimum, conduct such analyses based on US Coast Guard records, shipping company records, etc. Risk analysis of shipping is not a new field and needs to be applied to this plan for the lower Fox River. 

Throughout Section 5 and the entire BODR, the report states that large areas are covered with a “thin layer” of sediment with PCB concentrations of 1-2 ppm, far lower than the rest of the contaminated areas. The action level is 1 ppm, so the BODR states that about 210 acres are marginally contaminated.  The BODR fails to state that pretty much the entire lower Fox River is contaminated with PCB’s from the paper mill effluents and other releases. As a result, fish and other aquatic animals will encounter PCB’s in the entire habitat during all life stages. Admittedly, the 1-2 ppm is substantially lower than the highest concentrations that contaminate the river sediments. On the other hand, the BODR presents no data to indicate that 1-2 ppm are safe levels, or levels that do not result in significant harm to the aquatic system and people. Indeed, the ROD is based on a cleanup standard of 1 ppm PCB’s in sediment because higher levels do not provide protection of human health and the environment. The lower levels of contamination are coupled with extensive areas that will not be treated at all and the continuing discharge of PCB contaminated effluent from paper mills and POTW’s on the Fox River, and possibly other sources of PCB’s (i.e., leaking contaminated sites).

The BODR fails to accept the fact that PCB”s are sufficiently toxic that 1-2 ppm in sediments will certainly result in accumulation into the aquatic food web. PCB’s can increase in concentration by several hundred over the level in sediments or water (Rice et al., 2003). Tissue levels of a few ppb or lower can have serious reproductive and developmental effects on fish, birds and terrestrial mammals (e.g., mink). Mink suffered reproductive problems when fed a fish diet that contained 0.25 ppm PCB’s (see Rice et al., 2003). The Wisconsin water quality criterion of 0.003 parts per trillion is set so low because of the accumulative potential and enduring effects of these toxic compounds on humans and wildlife (see Rice et al., 2003 and references contained therein).

Monitored Natural Attenuation is not described and not even mentioned in this section that is supposed to give the details of the plan. This omission is a major flaw in the report. The BODR needs to spell it out and describe the areas where natural attenuation will be used and what evidence exists to believe that PCB’s will naturally breakdown in these sediments. Rice et al. (2003) describe some of the information on degradation and breakdown of PCB’s in the environment, noting that in the absence of sunlight and oxygen, such breakdown is a slow process. Given the fact that PCB’s discharged over many decades still remain buried in the Fox River, there is no reason to now believe that other PCB’s will not remain in the sediments in other parts of the river. 

Section 5.1 Design Goals

The third bullet states that the sediment removal will remove high level PCB contaminated sediments without disturbing sediments with lower level contamination or where there are logistical difficulties. The text here fails to note that “near 1 ppm” also means sediments that exceed 1 ppm PCB’s, despite the 1ppm action level for this site. The statement is also vague with regard to the criteria for what sediments are too difficult to remove or whether some are just more expensive than others to remove, and therefore the responsible parties want a less expensive method.

The fourth bullet makes all the assumptions about capping and fails to include the limitations. The statement also implies that all the caps will be armored, when such is not the case. Many caps, especially in shallow areas will not be armored and will only be sand caps that have no armor. The casual comment about institutional controls fails to convey the full sense and meaning of this control measure.  The bullet needs to include the fact that parts of the river will have legal limits on commercial and recreational activities forever. 

The last bullet on page 141 states that sediment removal will be done in a manner equivalent to the dredging described in the ROD, but this statement is so vague as to be disingenuous.  This statement is misleading.  This bullet needs to specifically state what method is equivalent to the one(s) in the ROD.

The second bullet on page 142 of this section claims that the original ROD cannot dewater the sediments on site because of the larger volume. This point is simply a thin excuse for weakening the cleanup. The problem with this statement is that the solution is being driven by what the responsible parties want to do, rather than what needs to be done to clean the river. If a larger volume or more space or additional equipment is needed, then financial resources need to be provided by the responsible parties to accomplish the cleanup properly, including obtaining the needed space. The first statement of the bullet needs to be removed.

The last bullet on page 142 of section 5.1 gives a cursory statement about monitoring, natural recovery and institutional controls.  None of these points adequately explains the full magnitude and significance of the three activities. Monitoring should be used to enforce, institute cleanup or determine effectiveness and will continue for decades. Natural recovery is a fancy way of saying that the responsible parties will do nothing. Institutional controls limit the use and access to the river and will last forever, the time that PCB’s will remain in the sediments of the lower Fox River.

Somewhere else the BODR needs to provide a complete and well documented analysis of capping effectiveness. If capping technology is considered to be so effective as to use it throughout the river to hold in sediments in surface layers, at depth and in low and high flow areas, then there must be some data on which to base this conclusion. The WDNR, EPA and responsible parties need to provide a technical analysis of caps that includes peer-reviewed literature, technical government reports, industry documents regarding the use of caps in rivers. This report needs to show the use of caps, the duration, contaminants capped, types of sediments, waterbody, and other information. This technical view needs to provide the results of monitoring efforts and documentation that the data are acceptable from a quality assurance quality control perspective.

Page 142 bottom- The bullet needs to state clearly that monitoring will be conducted for the foreseeable future so long as PCB’s remain in the river sediments. The text of this bullet also needs to state clearly that institutional controls are not the preferred approach and will place permanent restrictions on property use and use of the river. Finally, the bullet needs to indicate what information will trigger additional actions or work on this site.

Section 5.1.1

This section of the BODR summarizes the “new information” from the Remedial Design (RD) (sediment core data) used to justify leaving up to 40 % of the total PCB load in the river. On page 143, the first bullet refers to figures 2-21 and 2-22 for support of the statement that deeper sediments are more contaminated in parts of the river, and overlying, less contaminated sediments would have to be disturbed to get at the deeper sediments. The figures also indicate that sediment PCB levels at the surface or in shallow sediments exceed the 1ppm action level and should be removed anyway. These figures support the conclusion that the sediment is contaminated with toxic levels (determined in the ROD that set the 1 ppm level) of PCB’s and needs to be removed at depths as great as 10 feet (see Figure 2-23). This bullet text seems to attempt to justify leaving highly contaminated sediments (perhaps as high as 100 ppm) in place because they are deep, in the navigational channel and dredging these sediments will cost more money. None of these justifications is satisfactory in violating the terms of the ROD.

The second bullet on page 143 suggests that lower level contaminated sediments in shallow areas can be covered with 0.5 ft of sand as a remedy as effective as removing the contamination. First, this plan to place 0.5 ft of sand over large area of flats contradicts other statements that all caps will be armored. Placing 0.5 ft of sand is not an armor. Nor will there be any way to enforce institutional controls on this broad area cap of the river flats. Nor is there any evidence presented on the effectiveness of such a shallow cap of sand on top of a layer of more organic and lighter depositional contaminated material. The problem that may well occur is that the PCB contaminated material may not simply bury, but may end up in the surface sediments as a result of physical-chemical processes or biological activity in the clean sand. The text needs to state the uncertainty of this method and admit that these will be unarmored caps requiring institutional controls over vast areas of the river.

Bullet 3 on page 143 essentially concludes that it is too difficult to dredge the surface contaminated sediments that are near the RAL of 1 ppm. The BODR needs to make a substantive case for violating the conditions of the ROD other than it is a difficult task to comply with the ROD corrective action measures to protect health and the environment. The BODR does not seem to have any documentation that sediment layers of 0.5 ft cannot be removed without taking vast quantities of uncontaminated sediments as well.

The fourth bullet on page 143 in Section 5.1.1 anticipates Early Actions to remove some of the contaminated sediments with the highest PCB levels (3000 ppm). This plan is wise and should be taken up without delay. In implementing these early actions, the borders/ footprints and boundaries of the contaminated hot spots have to be carefully evaluated. 

Page 144, top bullet – the point that Congressional Reauthorization of the navigational depth must also note that this change has to be permanent and part of the Institutional Controls that prevent disturbance of these areas.

Page 144, third bullet- The text here points out that some of the deep contaminated sediments are located in areas that make dredging difficult or dangerous to the point of causing structural damage. Such areas have to be carefully examined and EPA needs to consider all treatment options. In places where highly contaminated sediments cannot be completely removed, other measures must be taken, including using reactive caps to enhance PCB breakdown, bind the PCB’s and reduce or eliminate the uptake of PCB’s into the aquatic food web.

Page 144, last bullet of Section 5.1.1- This bullet argues that there is nothing to do with the dredged contaminated material except put it in a landfill and that not enough landfill space is available for this project. The BODR fails to mention any of the newer treatment technologies that are available, including sediment washing that would then provide an end-product that does not require treatment such as hazardous waste landfilling and may even allow reuse as a clean material.  These comments include information on alternative treatment technologies for contaminated sediments.

Section 5.2.1 page 151, second bullet.

The example of a sand and gravel cap of 1.1 feet, about 13 inches, demonstrates the inadequacy of the cap remedy. Notwithstanding the modeling exercise on cap design, the 1.1 foot cap is hardly enough to physically protect and shield the water column from the contaminants.

The last bullet indicates that the dredging estimates conducted for the BODR are not capable of dredging only 6 inches of sediment, for reasons that are not explained and with no documentation. The BODR challenges credibility by suggesting that the dredge contractors and operators do not know how or are not able to dredge only 6 inches of sediment.

Section 5.3.1 Cap design criteria, Page 162. 

The design used a seiche amplitude of 4.3 feet over an 11 hr period. Will this account for the seiche that was documented by Paul Baumgart and is included in these comments as an appendix? In the seiche noted in 1990, flow increased from 12,000 cfs to about 48,000 cfs in a matter of about 6 hrs, and the seiche continued for more than 2 days. These measured results indicate that the modeled seiche is not sufficient to account for the observed sieches. 

Pages 163, last paragraph. This section gives the clearance between the top of the cap and the bottom of river ice that might threaten the cap below. The clearance given is only 7.2 inches in OU3 and only 1.2.inches in OU4. Neither of these clearances is sufficient to provide a margin of safety that can be expected to protect the integrity of the cap. A bit of debris or abnormal ice could protrude beyond the modeled depth of ice. In addition, more extreme weather conditions from global climate change can be expected to make weather conditions more severe than in the past.

Page 163 The BODR here states that “All cap designs presented in this BODR include gravel or larger armor materials.” And goes on to describe 210 acres that will only have a layer of sand placed on top. The subtle distinction between an armor cap and a sand cap is not lost on this review, but the public is certainly to be confused or deceived by the distinction. All caps are NOT armored- only the ones in deeper water in the navigational channel and nearby. The caps in shallow areas will just be a layer of sand. The BODR is deceptive in not clearly stating this fact.

Where are the data from other projects showing that this plan has any chance of success? The BODR relies on modeling to conclude that the deeper highly contaminated sediments will remain entombed forever and that the shallow sediments will gradually get better, go away or remain undisturbed (the BODR is vague on the fate of the PCB’s in shallow water sediments). There is no documentation of other sites or specific data on the success of this approach. The BODR should give specifics in river systems that are comparable in depth, flow, latitude, etc so that the public has some evidence that the plan for the lower Fox River is more than an inventive experiment with no factual basis for support.

Section 5.4.4, Page 172 .

The BODR presents some results of hydrodynamic modeling on water levels and flow. What will be the effects of hydrodynamic modifications on flooding and ice scouring? These points need to be addressed in this report.

Section 5.7 - Monitoring, maintenance and IC for Capping

Page 177. The BODR needs to explain how no anchor institutional controls will work in the recreational boating and fishing boat areas that are extensive in the Fox River.

Page 178, top.  This section has no information that usefully gives a vague idea of what type of monitoring is contemplated. The section needs to elaborate on the general goals and parameters of monitoring, especially monitoring of caps that must last forever and protect highly toxic PCB’s. 

Section 5.9 - Comparative Evaluation

Page 186. The BODR should include an option of using more equipment to conduct the operations, if shortening the duration of the project is needed. 

Section 6

This section details the sequence and schedule of construction and dredging operations for the cleanup. No comments at this time.

Section 7

Any capping in the Fox River would require long term monitoring and maintenance. The scheduling of these measures is outlined in this section. ESC agrees with the Science and Technical Advisory Committee (STAC) that the monitoring plan as presented is insufficient (Kennedy 2007). If a cap is placed in a high risk area such as the Fox River, monitoring should be done annually and in extreme detail. The entire cap should be checked after every winter using sonar imaging, [and] chemical and biological monitoring. Noticeably missing from this section is a discussion of how long such monitoring should continue. Because field data on the long-term (> 75 years) persistence of PCBs is unavailable, monitoring should continue indefinitely. 

Regardless of whether or not a cap is placed in the Fox River, a sufficient monitoring plan needs to be developed that would include congener specific analysis, biological tissue monitoring, as well as a phase analysis to determine if any detected PCBs are in particulate or dissolved forms. This would help evaluate the source of detected PCBs. This monitoring needs to extend into Green Bay as well. A remediation plan cannot be considered successful if the means to evaluate its progress are insufficient.

Section 8

This section compiles cost estimates for the various alternatives proposed for the remediation of the Fox River. No comments at this time.

Section 9

This section outlines the actions that WDNR and the EPA will take during the cleanup process to reach out to the various stakeholders involved in the cleanup, particularly during the selection process for the staging, dewatering, and disposal of contaminated sediments from the river. The plans presented here are sparse, as exact locations for many of these facilities have not been finalized. However, stakeholder outreach activities should include regular and direct contact with grassroots organizations such as the Clean Water Action Council. These groups represent the interests of local interests, and their opinions and concerns should be considered at the same level or higher than those held by the Fort James Operating Company and NCR Corp. A plan to involve these groups regularly beyond public meetings and comment periods should be presented.

Section 10

This section lists the references used in the BODR. No Comments at this time.

CONCLUSIONS

While the above are significant flaws, the fundamental problem with the “Optimized Remedy” is that it is only optimal in terms of lower costs and effort. Nearly half of the total PCB mass contained within the sediments of the Fox River will remain in place under the proposed plan. This is completely unacceptable, particularly given the uncertainties discussed above regarding the stability of the cap and toxicity of PCBs to humans and wildlife. Combine this with the use of monitored natural attenuation in higher reaches of the stream and the long term persistence of PCBs within sediment, the only sure way to insure the protection of water quality in the future is to remove all contaminated sediment. Alternative treatment options exist if landfilling is impractical.

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