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M � 10 February 1998 1997 Annual Report - 3 - ary Sharpe Facility contaminated groundwater. Therefore, a time schedule for all of the activities that are planned to be performed in this calendar year must be added to the Final 1997 Annual Report. In the meantime, the regulatory agencies are preparing a proposed detailed schedule of activities to be incorporated into the Federal Facilities Agreement. Specific Comments 1) Increasing concentrations, as shown by an upward trend in concentrations of TCE in downgradient wells in the North and South Balloon plume areas are noted on pages ES-2 and ES-3. Page ES-3, Sections ES 1.11 - ES 1.13, notes extent of VOCs in North Balloon A and B zones is increasing, the extent of the plume in B zone in the Central area is increasing and the plume in the South Balloon B zones has expanded. Again on page ES-4, Section ES 1.20 the Annual Report makes the statement that B and C zone extraction wells in the North Balloon only partially captured TCE plumes during the entire reporting period. The extent of the A zone capture zone in the North Balloon appeared to be reduced in the 3Q97 (page 4-7 Section 4.3.2.6) even after significant effort to increase pumping rates in this area has been made. The Report should describe actions recommended to address these increases in VOC contamination migrating away from the facility. The Report should, at a minimum, acknowledge the new 3D Modeling effort as recommended to evaluate how the current system can be optimized and identify potential modifications to the existing system to achieve complete capture in these areas. 2) The Annual Report shows that the overall system is only operating at 50% of the design flow so it is not surprising that Sharpe is not capturing the full plume. The North Balloon treatment system is designed to maintain 500 gallons per minute(gpm) but, calculation of monthly flow rates from Table 5.3-1 shows this system has been operating at an average of 245 gpm. Likewise, the Central Area is designed to operate at 750 gpm, and is operating on an average of 350 gpm. The South Balloon treatment system is designed to operate at 300 gpm and last year it pumped an average of 200 gpm. The Annual Report should provide specific actions Sharpe will take to run the treatment systems at design capacity and to achieve full plume capture. For example, in the South Balloon, Extraction well EWCB 1 is critical in maintaining capture of the B zone TCE plume. Increases in concentrations in MW455B and MW445C (which actually monitors the B zone also), MW50813, and MW523AB indicate that the extraction well system in the South Balloon is not operating properly or performing as expected. No observed capture zone is seen in the third quarter 1997 B or C zone maps (figure 5.3-2 and 3). EWCC3 was not operating in this period either. What specific adjustments to the extraction well flow rates will Sharpe make to optimize capture zones? Sharpe must propose specific actions with a time schedule to rectify these problems.