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The code also provides that the upper 24 inches upon which a mound is to be constructed have a percolation rate no slower than 120 minutes per inch and the maximum allowable slope is based on the percolation 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 measured in Test 4 is 22 mpi and where that average rate is faster than 30 mpi the code provides that up to 12% slope is allowable compared with the 11.5% that you measure from our contours. We note 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 important consideration in such designs. It would have been helpful to enumerate these tests and show calculation of the average to avoid confusion. Our draftsman plotted the location of Perc. Test No. 2 on the drawing and it is indicated by a dark dot as are the other tests but he failed to copy the label from the work drawing and we did not catch his omission upon review of the rather congested site plan. We note that during an initial site evaluation on a difficult site with limited space, the ultimate location of the treatment area may not be readily apparent. The evaluator may have to 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 percolation rates on site so that he is in a position to estimate the percolation rate no matter where the treatment area may finally be placed. If after a final placement of the proposed mound area is made, the location of the tests taken and the variability of the tests are such that testing under the actual mound site might produce results so different that they would materially affect the design, then these additional tests should be taken. In this instance, to render our basal area inadequate, we would have to find percolation rates greater than 31 mpi under the mound. We didn't feel and continue to feel that this is not at all likely in light of the tests taken and thus did not test further.