Jul 17 2008
GE’s Executive Summary for the Corrective Measures Study states:
… upstream remediation/source control activities, along with natural recovery processes, have significantly reduced the PCB loads in the Rest of River, and those improvements are continuing. Moreover, as documented in this report, remedial action would unavoidably damage the environment of the River and floodplain, including wetlands, mature growth trees, and the biota that live in the floodplain. In all these circumstances, GE believes that, other than monitoring the ongoing natural recovery processes, it is neither necessary nor appropriate to conduct additional remedial actions in the Rest of River area, with the attendant adverse impacts on the environment.
Nevertheless, while preserving its position, GE has, as required by the CD and Permit, conducted the evaluations in the CMS taking into account EPA’s HHRA and ERA and using the assumptions, procedures, and other inputs that EPA directed GE to use. Many of these EPA assumptions and directives with which GE disagrees have fundamentally shaped the analyses in this CMS. Accordingly, this CMS Report should not be regarded as GE’s endorsement of the conclusions set forth herein regarding remedial alternatives; nor does it constitute, given GE’s appeal rights under the CD and the Permit, a proposal by GE to implement those alternatives. (Emphasis added.)
Source: GE_Housatonic_Rest_of_River\Reports and Presentations\CMS Report\200811160 Executive Summary.doc, 6.
Here is a chart that summarizes GE’s conclusions:
It is not easy to make sense of all of this. There are two major components – what technology will GE use to clean the River and how much and which parts of the River GE is proposing to clean. If you look at the map of the River above you can see that GE is proposing to remove contaminated sediments and riverbank soils in Reach 5A and 5B. It is also proposing to cap (cover the contaminated sediment) in Reach 5C and Woods Pond. GE describes its proposal on page 22 of the Executive Summary:
ES.4 Overall Conclusion
Taking into account EPA’s HHRA and ERA and using EPA’s directives for the CMS, as required under the Permit, GE has concluded that a combination of alternatives SED 3, FP 3, and TD 3 is best suited to meet the General Standards of the Permit in consideration of the Selection Decision Factors, including balancing of those factors against one another. Taken as a whole, this would be a major remedial project – a 10-year construction and restoration project involving the excavation and disposal of over 225,000 cubic yards of sediment and soil, at an estimated combined cost of $184 million. As noted above, this conclusion is subject to GE’s reservations of rights, including its appeal rights, and thus does not constitute a proposal to implement these alternatives. (Emphasis added.)
HOW DID GE GET TO THIS POINT?
The Consent Decree required GE to “implement a process which is designed to result in a remedy decision for the downstream portions of the Housatonic River that is protective of human health and the environment” and then called for GE to perform “the Rest of River cleanup.”
The terms of this process were spelled out in detail:
a – EPA to conduct additional sampling, human health and ecological risk assessments and modeling.
b – A Peer Review Panel will review the human health risk assessment, ecological risk assessment and modeling performed by EPA.
c – GE to compile all data into an investigation report and evaluate remedial alternatives under a modified process which limits appeals until after a final remedy has been chosen.
d – At conclusion of studies, EPA will issue a Statement of Basis that selects a river remedy and modify GE’s RCRA permit to obligate GE to perform the cleanup.
e – GE agrees to perform the selected cleanup after completion of any dispute resolution under Consent Decree:
▪ Dispute resolution may include review by the EPA Environmental Appeals Board and the United States Court of Appeals for the First Circuit.
▪ During dispute, all work not subject to the dispute continues, and EPA can proceed with designing aspects of the Rest of River cleanup that GE has disputed, and under certain conditions may proceed with implementation of the work.
As required by the EPA’s Reissued RCRA Corrective Action, GE issued its Corrective Measures Study report for the Rest of the River. In March 2008, the EPA issued a summary of the GE study:
The purpose of the Corrective Measures Study (CMS) performed by GE as required under the Consent Decree (CD) is to evaluate potentially applicable technologies and cleanup alternatives for the Rest of River to reduce risk to human health and the environment from exposure to PCBs.
Description of the Technologies Evaluated in the CMS
Many of these technologies can be applied to in-place sediment, riverbanks, and floodplain soil. The treatment and disposition technologies apply to material after it has been removed from the river, banks, or floodplain. All alternatives (except No Action [NA]) possibly will require engineering and/or institutional controls. All alternatives include a restoration (except NA and MNR), operation, maintenance and monitoring component (except NA).
No Action The No Action (NA) response does not include any active or passive remediation or long-term monitoring. EPA requires that a No Action response be considered at every site.
Engineering/Institutional Controls There are four general types of institutional controls to reduce exposure to humans:
1. governmental (e.g., fish advisories); 2. proprietary (e.g., deed restriction); 3. enforcement (e.g., provisions in the CD [Consent Decree]); and 4. informational (e.g., public education).
Monitored Natural Recovery (MNR) MNR is a response action that relies on ongoing, naturally occurring processes (including physical, biological, and/or chemical mechanisms) to
contain, destroy, or otherwise reduce the bioavailability or toxicity of contaminants in sediment, with monitoring to assess the rate of recovery. MNR may also include enhancements, such as thin-layer capping, to accelerate the rate of recovery.
Removal Removal techniques include mechanical excavation in the “dry” as was performed for the 2 miles of the East Branch that have already been cleaned up, or removal in the “wet,” commonly referred to as dredging. Excavation in the dry is typically performed using conventional excavation equipment. Dredging may be conducted using either mechanical or hydraulic equipment. Removal of sediment or bank/floodplain soil often is coupled with backfilling using clean material to meet original elevations and contain any residual PCBs, and also requires one or more treatment and disposition alternatives for implementation.
Capping This technology requires the placement of a layer of clean material over the in-place contaminated sediment/soil, at a thickness suitable to create a clean bioavailable zone and to isolate the contaminated material. Depending on site-specific objectives, the cap design may include materials to enhance the isolation (e.g., geotextiles) or sorption of contaminants (e.g., organic carbon), and a protective layer (e.g., armor stone) to prevent erosion.
Bank Stabilization Stabilization of the banks is required when the potential remains for erosion of in-place contaminated bank soil. Stabilization techniques range from bioengineering to hard engineering (e.g., armor stone), and the use of a particular technique is dependent on bank slope/stability and water velocities.
Dewatering/Water Treatment Dewatering and/or water treatment is often a necessary step in the handling of materials that are removed, particularly sediment, to facilitate treatment and/or disposal of the material.
Ex-Situ Stabilization This technology is being included in the evaluation for potential use in sediment/soil handling as a means of dewatering, reducing the leachability of contaminants, or to modify the structural properties of the material. This involves mixing the sediment/soil with a stabilizing agent (e.g., Portland cement, lime, kiln dust, fly ash).
Chemical Extraction Mechanical separation methods combined with an extraction fluid can potentially be used to desorb PCBs from sediment/soil after removal, resulting in a large reduction in the volume of contaminated material. At EPA’s request, GE is performing a study of the effectiveness and implementability of this technology on site-specific sediment and soil samples. The potential for reuse of the material after treatment is a significant consideration with this technology.
Thermal Desorption Thermal desorption separates the PCBs from the sediment/soil by adding heat to the material. The heat then volatilizes the PCBs, which are then condensed as a liquid, captured, and/or destroyed in an afterburner, resulting in a large reduction in the volume of contaminated material. The potential for reuse of the material after treatment is a significant consideration with this technology.
Confined Disposal Facility (CDF) CDFs involve the placement of contaminated sediment/soil in an engineered structure constructed in a nearshore environment in such a way as to permanently isolate the PCBs from the environment.
Upland Disposal Facility After dewatering, sediment/soil is placed in an engineered upland landfill typically constructed in close proximity to the river but outside the floodplain. The facility is engineered appropriately to permanently isolate the PCBs.
Off-Site Disposal Facility After dewatering and pretreatment to achieve other requirements of the disposal facility, sediment/soil would be transported to an existing, licensed offsite landfill.
Despite the efforts of many in the environmental community to convince GE to use more innovative alternatives clean-up technologies, GE opted for the same combination of dredging, capping, and landfilling that GE and EPA employed in the first two miles of clean-up.
GE then addressed the issue of how much and which sections of the River it thought it needed to clean. GE summarized 8 different alternatives:
Note that the term “capping,” when used alone, refers to engineered capping; thin-layer capping is identified separately and refers to a 6-inch sand cover used to enhance natural recovery. The term “removal” refers to removal followed by capping (or, for SED 7 and SED 8, removal followed by backfilling), unless otherwise indicated.
• SED 1 – No action in all reaches.
• SED 2 – MNR with institutional controls in all reaches.
• SED 3 – Sediment removal in Reach 5A, MNR in Reach 5B, a combination of thin-layer capping and MNR in Reach 5C, thin-layer capping in Woods Pond, and MNR for the remainder of the Rest of River.
• SED 4 – Combination of sediment removal, capping and thin-layer capping from Confluence to Woods Pond Dam. This alternative involves the same elements as SED 3 with the addition of sediment removal and thin-layer capping in Reach 5B and Woods Pond, capping in portions of Reach 5C, and thin-layer capping in portions of the backwaters.
• SED 5 – Combination of sediment removal, capping, and thin-layer capping from the Confluence to Woods Pond Dam and thin-layer capping in Rising Pond. This alternative involves the same elements as SED 4 with additional sediment removal in Reaches 5B and 5C, capping alone in a portion of Woods Pond, and thin-layer capping in Rising Pond.
• SED 6 – Combination of sediment removal, capping, and thin-layer capping for the entire River from the Confluence to Woods Pond Dam, and a combination of capping and thinlayer capping in the Reach 7 impoundments and Rising Pond. This alternative involves the same elements as SED 5 with additional removal in Reach 5C and the backwaters, thin-layer capping in the Reach 7 impoundments, and a combination of capping and thinlayer capping in Rising Pond.
• SED 7 – Combination of sediment removal, capping, and thin-layer capping for the entire River from the Confluence to Woods Ponds Dam, in the Reach 7 impoundments, and Rising Pond. This alternative involves the same elements as SED 6 with additional removal in Reaches 5A and 5B and backfilling rather than capping in those reaches, additional removal in the backwaters and Woods Pond, and sediment removal in portions of the Reach 7 impoundments and Rising Pond.
• SED 8 – Removal of sediments, followed by backfilling, in all areas of the main channel
and backwaters of the River between the Confluence and Woods Pond Dam, in the Reach 7 impoundments, and in Rising Pond, with the depth of removal set as the depth to which PCBs above 1 mg/kg are estimated to occur (1 mg/kg depth horizon), and MNR for the remaining portions of the Rest of River.
Where these alternatives specify a combination of remedial technologies (e.g., removal and capping) for a specific reach or subreach, the areas where each technology would be applied were described in Section 3.1.1. In addition, each of the above alternatives (except SED 1 and SED 2) includes removal and stabilization of erodible riverbanks containing PCBs in Reach 5. Further, each alternative includes (or, in the case of SED 1, assumes) the continuation and maintenance of biota consumption advisories as necessary to limit the public’s consumption of fish and other biota from the River.
Source: GE_Housatonic_Rest_of_River\Reports and Presentations\CMS Report\200811160 CMS Report.doc ,4-1 & 4-2
There is a large range in costs associated with each choice of remediation technology and disposal and how much of the River gets cleaned. GE created this chart:
This is how the EPA describes GE’s final choices in its CMS fact sheet:
GE’s Recommended Alternatives
As required by the RCRA Permit, GE presents in the CMS Report its conclusions as to which remedial alternatives, in its opinion, are “best suited” to meet the Evaluation Criteria described on Page 4. GE has concluded that the combination of alternatives SED 3, FP 3, and a local upland disposal facility is best suited to meet the criteria.
These alternatives involve the removal of approximately 167,000 yd cubed (~250,000 tons) with capping of river sediment and bank soil over 42 acres of the river between the Confluence and the vicinity of New Lenox Road (approximately 5 miles), MNR in Reach 5B (approximately 2 miles) and the upper 1.8 miles of Reach 5C, and placement of a thin-layer cap in an additional 97 acres of river in the downstream portion of Reach 5C (approximately 1.5 miles) and Woods Pond, with MNR in the remaining areas. In addition, these alternatives include removal of approximately 60,000 yd3 (~90,000 tons) of soil from 38 acres of the floodplain. The river sediment and bank and floodplain soil
removed would be contained in an upland disposal facility located in an area near the river but outside of the 100-year floodplain.
GE estimates that following design and site preparation, these alternatives could be implemented within 10 years at a cost of approximately $184 million.
A variety of stakeholders have weighed in with a range of suggestions for the EPA as it decides whether to accept the GE proposal as it stands or to request modifications. You can download these comments on our Documents page and read them at your convenience.
Here is just a small sampling of the public comments:
The U.S. Fish and Wildlife Service suggests 2-foot removal and full-scale in place capping in several additional areas of the River. For example, while GE suggests thin-layer capping for Woods Pond, U.S. Fish and Wildlife writes:
Conduct 2-foot removal with full-scale in-situ capping in shallow areas not subject to scour, 3-foot removal with backfill and capping in areas prone to high scouring and with PCB concentrations significantly elevated above the IMPGs at depth …
Berkshire Natural Resources Council made the following comments:
Berkshire Natural Resources Council is writing to encourage the EPA to require substantial revision and improvement of the Housatonic River “Rest of River” Corrective Measures Study. The study includes numerous shortcomings. It fails to provide for an effective adaptive
management process. It fails to incorporate the cost and standards of restoration, or to
convincingly explore alternative remediation technologies. The process as currently defined
does not provide a meaningful role for the Commonwealth and important stakeholders in the
decision making process. Most importantly, the CMS fails to establish a plan that will lead to a
clean-up resulting in a clean, fishable, swimable, and naturally functional river …
There is an understandable desire shared by most stakeholders for an expedient clean-up. However, the natural and human environment will be better served by a careful and stepwise process executed over a number of years. Stepwise, as each reach or even each mile is cleaned and restored or reclaimed, valuable experience will be gained to inform the clean-up of the next mile. A slower progression will allow trees along the river bank to grow and provide shade for the fishery before large areas downstream are opened to the daylight. During a deliberate stepwise progression natural communities will have more time to disperse and re-colonize disturbed sites and the human community will be less impacted and be better able to manage the complexity of the system at hand. Granted, any cleanup will not be fast, but taking deliberate pauses between short stretches of river will lessen the impacts and improve the over all cleanup.
Mass Audubon suggested that GE’s proposal failed to adequate provide assurances for effective restoration of affected areas of the River:
After review of the 800+ page CMS, we are surprised to see virtually no information about restoration of affected habitats, and note that such information is required by Condition #4 of EPA’s Conditional Approval letter for the Corrective Measures Study Proposal dated April 13, 2007. For example, there has been widespread public criticism of the approach to bank restoration and stabilization in the upstream 1 ½ miles of the Housatonic River. We share the public concern about this work. While it may be achieving the result of creating an aesthetically acceptable vegetated river bank, we do not believe that functionally equivalent habitat has been created that adequately “replicates” the preconstruction functionality of the bank, and have not seen any studies suggesting that it has. We are similarly concerned about restoration of functional floodplain forest habitat, vernal pools, and river bottom habitat as we have not seen any studies to date that suggest that GE has fully restored functional habitat in such resource areas along the River. If such information exists, it should be provided in the Supplemental CMS.
The Housatonic River Initiative received a Technical Assistance Grant from the EPA. Peter DeFur was hired to review the GE CMS. He wrote:
No Innovation. Innovative methods and alternative technologies are all but absent. The only mention of alternatives is use of Thermal Desorption of PCB’s from dredged sediments, hardly a new or innovative method. This lack of innovation may in part stem from the federal Superfund act, CERCLA, which seems to have no incentive for new technologies. This feature of Superfund stands in stark contrast to the Clean Air and Water Acts which are intended by design to force new technologies by rewarding companies that use them. Not so with Superfund for either the companies conducting the cleanup or EPA and other agencies responsible for overseeing the efforts.
Innovative methods for cleaning contaminated dredged materials are more numerous than presented in the CMS. The CMS considers thermal desorption, but not sediment washing, sonic removal, deactivation of the contaminants or other such methods.
Two in situ methods of note are worth considering in the CMS under the present circumstances. First, researchers at Renselaer Polytechnic Institute have identified the bacterium that can breakdown PCB’s (Bedard et al 2006 and 2007). In a paper about to appear in the April issue of Applied and Environmental Microbiology, Bedard et al (2007) describe isolation, and effectiveness of the bacterium that is responsible for anaerobic dechlorination of PCB’s. This process removes chlorine (substituting H) from the most accumulative, toxic PCB’s, rendering them far less toxic and accumulative and also susceptible to aerobic degradation. Bedard et al (2007) state: “Hence, through the combined action of anaerobic processes N and LP, highly chlorinated PCB congeners can be dechlorinated to PCB congeners with a low degree of chlorination that are susceptible to aerobic degradation and mineralization (i.e., complete detoxification).”
This discovery is a major step in the development of bioremediation processes for such compounds. The two pathways for bacterial breakdown of PCB’s are with oxygen (aerobic) or without oxygen (anaerobic), the latter being more effective in removing chlorine from the highly substituted congeners.
The second “in situ” method is known as “Oil-Free Technologies” and has been used to breakdown chlorinated (and non-chlorinated) organic wastes at a number of European sites. This method uses an enzyme extracted from earthworms to inject into soils and sediments and breakdown the contaminants. The web site, www.oilfreetech.com/index.htm, provides additional details on the effectiveness of removal and loss of PCB’s from contaminated sediments and soils.
Both of these methods offer the opportunity to remediate contaminated sediments or soils without dredging or the massive disturbances of soil removal and replacement. Given the fact that this cleanup process will continue to take many years, the fact that these have not yet been used is not sufficient justification for ignoring these innovative opportunities.
Download these and other comments on the Documents page.