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The code also pro'4 • pies that the upper 24 inches ipon which a mound is to be constructed have a percolet ion rate no slower than 120 minutes per inch and 'he maximum allowable slope is based on the percoiatio. rate in that 24 inches. Tests 2 and 4 were taken to check that this requirement was met and that maximum slopes were not exceeded. The average of the 33 mpi rate measured in Test 2 and the 11 mpi rate me-asured in Test 4 is 22 mpi and where that average rate is faster than 30 mpi the code provides that up tL- 12% slope is allowable compared with the 11.5; that yo- measure from our cor..ours. We nol.- further that page E-8 of the On Site Sewage Treatment Manual suggests that recent research and analysis indicate that basal width and not slope: is the importz consideration in such designs. It would `eve been helpful to enumerate these tests and show ci lation of the ave-age to avoid confusion. .ur draftsman plotted the location of Perc. Test No. )n the drawing and it is '�ndicated Ly a dark dot as are .he other tests but he failed to copy the 1, from t::e work drawing and we did not cater his omis:. u...c_.r review of fle rather congested site plan. We note that during an ini*ial site evaluation on a difficult site with limited space, the ultimate location of the treatment 1.rea ►nay not be readily apparent. The evaluator may have tc use his best estimate of where the treatment area may be located and then sample in a way that gives him an overall feel for the percoiz�! ion rotes on site so that he is n a position to estimate the percolation rate no n.. er where the--eatment area mar finally be placed. If after a fi,,dl placement of the proposed mou; rea is made, the location of the tests taken the vEriability of the tests ai Such that test_ under the actual mound site migt-,t produce rei.uitD so different that they would materially affect the desi-n, V there additional tests mould be taken. in this ii .ance, to ten-tour basal area inadequate, we would hav to find pv--lation rates Greater than 31 mpi under the mound. We uidn't feel and continue to feel that this is not at all likely in light of th- tests 3ken and thus did r-t test further.