SITE INFORMATION AND CORRESPONDENCE_1993-2003

Home Browse Search

Draft Final ROD Memorandum -2- 22 December 1992 DDRW, Sharpe MAJOR ISSUES Substantive Waste Discharge Requirements The SWDRs were not acknowledged in the text of the Draft Final ROD nor were the SWDRs included as an attachment to the ROD as directed by the EPA in the 12 November 1992 letter. The SWDRs must be referenced in text and attached to the ROD as these meet the substantive requirements of our ARARs as a permit is issued by the Regional Board for waste discharges to land. The text of the ROD should be revised in the following pages and sections: Page Section Subject 44 7.1.1 Aquifer Remediation Levels 7.1 .2 Treatment Plant Effluent Discharge Standards 53 to 54 8.6 Implementability 54 8.8 State Acceptance 67 to 69 9.3 Ground Water Discharge 72 10.2.2 Action Specific ARARs Three-Dimensional Model The Draft Final ROD did not incorporate any of the results of the 3-D numerical model which proposed significant changes in the extraction wells and well field design, the treatment system, the disposal system and the duration of the remedial action. The 3-D Modeling Report proposed a more efficient extraction system (as acknowledged by Sharpe's 21 October 1992 letter) , proposed that only one treatment plant would be necessary rather than two, predicted the affects of the pond and the injection wells in separate areas, as well as, optimization of the injection well field and predicted that the duration of the remedial action would be between 30 to 40 years rather than 16 years. In a conversation with Mr. Craig MacPhee, of USATHAMA, on 18 December 1992, he indicated that the results of the 3-D modeling would be used preferentially to the results of the two-dimensional (2-D) modeling for the RD. The extraction system for the Central Area is to be installed under USATHAMA. In addition, in conversations with Mr. Mike Williams, of the COE, on 17 December 1992, he also indicated the results of the 3-D modeling would be used for the RD of the treatment and disposal systems. Based on these conversations with USATHAMA and the COE, it is clear that use of the 3-D model is preferred for the RD. Therefore, it is reasonable to request that the Draft Final ROD reflect that 3-D modeling was performed and that recommendations and predictions for the extraction, treatment and disposal systems, as well as the duration of the remedial action, be reflected in the Draft Final ROD. Below are listed the major areas of the Draft Final ROD that should have the text revised to reflect the results of the 3-D modeling effort.