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Prior to cleaning and decontamination, the tanks may contain bacteria, bacterial spores, <br />viruses, and fungi. These microorganisms have differing resistance to disinfection and <br />sterilization efforts. In particular, bacterial spores are more resistant than other <br />rmcroorgamsms. <br />Powertech's SOP does not specify the concentration of bleach that will be applied to the <br />interior of the tanks. The contact time, from application to drying, is not specified. <br />These parameters determine the efficacy of any disinfection or sterilization procedure. <br />Powertech does not indicate whether its standard is low-level disinfection, high-level <br />disinfection, or sterilization, which includes inactivation of bacterial spores. And the <br />SOP does not address whether household bleach or EPA-registered sodium hypochlorite <br />will be used. <br />4. The tank inspection procedure is non-specific and inadequate to detect the <br />presence of pathogenic microorganisms. <br />,Powertech's SOP for inspection of the tanks following cleaning and decontamination is <br />deficient. It calls for Powertech employees to "visually inspect the interior, exterior, and <br />valves of the vessel to ensure cleanliness. Do not enter the vessel." <br />It is unclear how tanks this large can be adequately inspected by looking through a couple <br />of 22-inch manway ports. <br />No testing for the presence of chemicals or microorganisms is required. <br />5. There is no plan to control the temperature of the injectate stored in the tanks to <br />inhibit bacterial growth. <br />Once the tanks are filled, it is unclear how long the injectate will be stored in the tanks <br />before injection into the receiving aquifer. Increases in the temperature of the injectate <br />could potentially accelerate growth of bacteria left in the tanks or introduced during the <br />pump test. Powertech has no plan to monitor and control the temperature of the injectate <br />to curb growth of bacteria. <br />6. The Draft Permit and Statement of Basis contradict each other with respect to <br />sampling and analysis of the injectate before injection. <br />Due to the risk of chemical and biological contamination of the injectate resulting from <br />storage of the pump test water in potentially contaminated tanks and bacterial growth <br />during the storage period, the injectate from each tank should be sampled and analyzed as <br />close to the time of injection as is practical. <br />The Statement of Basis indicates that Powertech will sample the stored groundwater and <br />have it analyzed before injection occurs. However, the Draft Permit explicitly does not <br />require sampling and analysis. <br />3