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A one inch rain storm failing on the 30,000 sqft drainfield will amount to 16,290 gallons. Even with a one inch storm and sewage flow, the site can still accept six times more water. Another way to look at the relationship of flows added, versus the absorption rate of the drainfield, is to use Darcy's Law. The tests show the average saturated K value for the soil below the drainfield is 1109 sqft/day. Using Darcy's equation we can answer the question of how much area is really needed if there was no reduction of flow rates with time. i Q= 1109 'K =2.3 i i = 1 A= ? Q=AKi 1109=AX2.3X1.0 A=482 SQFr Darcy's equation says 482 sqft will be needed to absorb the flows. The drainfield will have 30,000 sqft or 60 times as much as is needed. The extra capacity is to avoid clogging the soil. A continuous application of even well water will clog soil pores with biological growth. By reducing the loading rate and dosing, a relatively high rate of intake can be maintained indefinitely. 'This drainfield is being built to serve this development for a very long time. The chance of a public sewer system is negligible. The drainfield must work as the permanent solution. By lowering the application rates, this can be accomplished. (3) Figure 3 shows the location of two wells used to characterize the ground water j under the proposed subdivision. Well A is on Mr. Kramer's property. It has been serving his residence for over 40 years. Well B-6 is a well drilled by Kleinfelder. It was drilled on May 1, 1990. Elevation of water levels on May 1, 1990 were 45 feet for Well A and 58 feet for Well B-6. (This is the elevation of water not distance from ground surface. The depth of well A is about 120 feet. Water is at 80 feet below the surface. Well B-6 is 30 feet deep. The water.is 27 feet below the surface.) I 6