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5 <br /> pressure from either or both of the Hancor and the Boone pumping stations. Failure of the service <br /> connection or valves could result in the discharge of thousands of gallons of sanitary waste and the <br /> undermining by hydraulic erosion of US 70. Mitigation of environmental consequences, repair of damages <br /> to US 70, etc., would be the legal and financial responsibility of the County. <br /> Yet another technical consideration at the Hancor tap (that was not a significant consideration at the <br /> Lloyd tap)would be the control of the timing for the operation of the separate pumping systems serving <br /> Hancor and the mobile home park. If the pump stations were set up such that they were allowed to <br /> operate(pump) simultaneously, the pumping capacity, in terms of flow rate, of each station would be <br /> reduced by fifty to seventy-five percent. The reduced pumping rate would lower pumping efficiency, <br /> increase pump run times and raise pumping costs in terms of power consumption and equipment wear. <br /> One solution for the problem of simultaneous pumping would be to install automatic timers that would <br /> eliminate simultaneous pumping by controlling the time(s) of day each pump station could operate. This <br /> process would have to be designed very carefully to insure that neither of the pump stations' holding or <br /> storage capacity was exceeded during the no-pump periods. Establishing the timing-storage relationship <br /> equation could be difficult for the Hancor facility as the pump station storage volume has already been <br /> fixed. <br /> There is no question that a fully functional Hancor force main could accommodate Hancor's currently <br /> projected flows along with those which would be projected for either a ten or twenty unit mobile home <br /> park. Hancor has indicated that it plans a significant expansion of its plant within the next several years <br /> and there is also some question as to the current functionality of the Hancor force main. Hancor's recent <br /> sewer use billings, which are based on calculations involving total monthly running times for the <br /> wastewater pumps, have shown that Hancor pumping station is actually pumping for up to twenty hours <br /> per day. As this pumping time was judged to be excessive from an operational standpoint and the resulting <br /> flow rates calculations indicated flows far in excess of projections, an evaluation of the pump station was <br /> conducted on March 4, 1997. The field test of the Hancor pumping station's pump rates and run time <br /> meter accuracy showed that the Hancor wastewater pumps were pumping at a flow rate of approximately <br /> ten percent of their capacity as designed and as observed and calibrated at the April 1993 pump station <br /> start-up. Additional analysis and evaluation of the pumps and force main is being undertaken to determine <br /> if the problem stems from a blockage in the force main or from a mechanical problem with the pumps or <br /> pump mountings. If the problem does stem from a force main blockage, the blockage must be located and <br /> removed. If current circumstances were such that: a)both Hancor and Boone mobile home park were <br /> using the force main; and b)there was a blockage of some sort in the portion of the force main downstream <br /> of the interconnection, it is probable that Hancor and Boone home mobile park would be unable to discharge <br /> their full wastewater loads via the force main. Under this scenario, even the use of coordinated pumping <br /> timing controls would not suffice to permit full operation of both the Hancor and mobile home park <br /> wastewater systems. <br /> The potential policy implications of allowing the tapping of the Hancor force main are complex. Allowing <br /> the tap may stimulate property owners along both the Hancor force main and the Efland system's primary <br /> force main to seek to obtain sewer service by means of tapping the force mains. County staff has already <br /> spoken with several individuals who own property adjacent to the force mains and who want or need <br /> sewer service. In dealing with the request for the Ben Lloyd force main tap, County staff was able to create <br /> an exception to the County force main tapping policy that was limited to exactly the circumstances of that <br />