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residence was determined by Petralogix to be 91,250 gals. Pounds of nitrogen in this volume= 91,250 gals x 0.000291756 lbs nitrogen/gals=26.6 lbs of nitrogen spread over 875 ft2 filter bed area, or 0.0304 lbs nitrogen/ft2. Based on the 50%reduction in total nitrogen requirements as referenced above, 13.3 lbs of nitrogen(50% of 26.6 lbs)would have to be treated by vegetative uptake; readily achieved by the fescue grass by removing 29.2 lbs N in 18 cuttings. The ammonium fraction of the wastewater, which constitutes approximately 80%of the septic tank-treated effluent is immediately available for uptake by the Fescue grass. The remaining 20%organic fraction must undergo ammonification before uptake. The total nitrogen is used since it is assumed this 20%will eventually undergo ammonification. MONITORING PROGRAM To determine nitrate concentrations from vadose zone water under the EZFIow tubes, a Soil Solution Access Tube(SSAT)manufactured by the Irrometer Company is proposed, as illustrated in the attached data sheets. I am proposing to use this device to sample effluent that has percolated into the vadose zone under the EZFIow modular tubes. As-builts must be provided by the installer specifying the exact location of the filter bed perimeter, either by placing stakes or some other marker at the four corners, or tying one filter bed corner distance to a fixed object. A hand auger will be used to drill a boring in between the tubes. A 48" SSAT will be installed, then extraction of a vadose zone water sample from at least 1 ft below the soil-effluent interface will be obtained by suction. Two samples locations are proposed: one from the top of the filter bed, and at the end of the filter bed, as illustrated on the design plans. The Monitoring Program should begin after the Fescue grass has had time for its root structures to grow down and around the EZFIow tubes, which would be after one growing season. I am proposing to sample and analyze influent from the first compartment of the septic tank and an effluent vadose zone sample on the first of January,then at the end of January; the first of April then the end of April; first of August,then the end of August;the first of October, then the end of October after the first year of operation. Sampling and analysis would then be conducted again under the same protocol of any given year. However,the EHD may reduce the sampling frequency after one year of sampling,as specified in Item 1 d. of the EHD directive. Analysis would include the organic,ammonia and nitrate fractions of nitrogen, along with total alkalinity and pH. Reference is made to the Regional Water Board OWTS Policy Document, Section 10.9.1,which states"Effluent from the supplemental treatment components designed to reduce nitrogen shall be certified by NSF, or other approved third party tester." The vadose zone water samples will be analyzed by an Environmental Laboratory Accreditation Program(ELAP) Certified Laboratory,thus meeting the requirements of an approved third parry tester. Page -4- Chesney Consulting