Title
Koppers Superfund Site Expert Panel (NB)
Explanation
The Koppers site was first designated as a Superfund site in 1983. The Koppers site, which is located approximately 2 miles from the City of Gainesville Murphree Wellfield, is contaminated due to past wood treating operations. Due to the nature and extent of the contamination, and the proximity to the Murphree Wellfield, the site presents a significant potential long-term threat to the City's drinking water supply.
Although the site has been studied extensively since 1983, there had been minimal investigations to determine the depth of the contamination at the site prior to 2001. At the urging of the City of Gainesville, Alachua County and other stakeholders, additional investigations have been performed over the last 3 years by the party responsible for the site cleanup, Beazer East, Inc., to better assess the extent of contamination. These recent investigations have indicated that contaminant source material has penetrated deeper into the ground than had previously been thought. In response to these developments, the City has escalated its efforts to ensure that decisive actions are taken to prevent contamination from reaching the City's wellfield and for proper cleanup of the site.
At the October 25, 2004 City Commission meeting staff provided an update on the Cabot/Koppers Superfund site and the Commission authorized the engagement of an expert team of consultants to advise the City with regard to the Koppers site and assist the City in ensuring appropriate and decisive actions are taken.
In January 2005 the expert team provided a report with initial conclusions and recommendations on the site. This report was forwarded to the City Commission on January 5, 2005. Since that time, a number of detailed efforts have been required from the team, including detailed review of the groundwater model being used by Beazer, detailed review of site geology and contamination, development of detailed recommendations for additional Floridan Aquifer monitoring and review and comment on remedial investigation workplans.
At this time, key conclusions from the expert team include: 1) There is significant contamination in the Floridan Aquifer below the Koppers site (Beazer maintains that high concentrations detected are the result of well construction problems); 2) Large amounts of creosote, arsenic and other contaminants exist in the surficial and intermediate aquifers beneath the site, which will continue to move downward and further contaminate the Floridan Aquifer, unless the site is remediated properly (Beazer maintains that source material has reached a steady state condition and is not mobile); 3) The existing Floridan Aquifer monitoring wells are not adequate to fully determine the extent of contamination in the Floridan Aquifer. 4) Beazer's contaminant transport model (which indicates that there is no threat to the wellfield) is driven by certain key assumptions, some of which are being challenged by the expert team.
The team has recommended immediate actions to protect the water supply, including: 1) Interim measures be taken to contain the contamination in the Floridan Aquifer under the site to keep it from continuing to move toward the wellfield; and 2) Additional wells be installed on the site to better assess the extent of Floridan Aquifer contamination.
The team has recommended that, to ensure the site is properly cleaned up, contamination must be removed from the surficial aquifer, more investigations must be performed to define the extent of contamination in the intermediate aquifer, and the intermediate aquifer must also be remediated to stop the contamination from continuing to move downward into the Floridan Aquifer.
At this time, no plans have been developed for interim measures to contain the Floridan Aquifer contamination. Beazer has been unwilling to install the additional Floridan monitoring wells as recommended by the expert team. In addition, Beazer has continued to maintain that contamination in the surficial and intermediate aquifers is not a threat and does not need to be removed, and has not proposed further steps to adequately characterize the site. USEPA has yet to take positions on these and several key technical issues regarding the site.
It is critical that the appropriate site characterization steps be taken for the appropriate remedies to be selected for the site. Staff is proposing to have the expert team develop a "Specific Recommendation Report" which will spell out detailed testing and analytical work to be completed in order to fully characterize the site and allow appropriate measures to be taken.
The level of threat to the wellfield, the complexity of the site, and the remaining issues which have not been addressed by Beazer and EPA have necessitated a much more detailed and extensive effort than was originally budgeted for this project. Staff is proposing that the budget for the expert consultant team be increased to $400,000. This budget will cover costs to complete the Specific Recommendation Report and the detailed reviews currently underway through the end of FY 2005.
Recommendations
The City Commission hear a brief presentation from staff on the status of activities at the Koppers Superfund site and progress of work by the expert team of consultants assembled to advise and assist the City of Gainesville with regard to the Koppers Superfund site.
Fiscal Note
The original estimate for the consulting project was $160,000.00. The revised cost of the team is estimated at $400,000 to complete activities through the end of FY2005. This project will be charged to the Water Treatment capital budget.
Drafter
Prepared by: Rick Hutton, P.E., Senior Water/Wastewater Engineer
Submitted by: Michael L. Kurtz, General Manager