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infiltration tests. The basins were provided by an outside contractor and consisted of prefabricated 10-foot <br /> diameter, 30-inch tall, 3/16-inch thick, aluminum "rings" which served as the walls of the basin as shown <br /> here. <br /> Excavations were made that were sufficiently deep enough to allow the basins to be set in the sandy soils. <br /> After being set in place, material was placed behind the walls of the test basins to secre them in place. <br /> Both basins were provided with water by means of a fire hydrant on the transfer station property. Fire hose <br /> was laid from the hydrant to the basins. Basin Number 1 was approximately 600 feet from the hydrant, <br /> whereas Basin Number 2 was approximately 1,200 feet from the hydrant. The Mashpee Water District <br /> provided the water meter and backflow preventer. A valve for controlling flow was located at each test basin. <br /> 2.3 Constant Head and Falling Tests <br /> A series of tests were conducted at the basins over,a one-week period.,Appendix C includes selected <br /> photographs taken during the testing. One basin test was conducted at a time. Each series of tests took <br /> three days. The testing was completed on the schedule as illustrated in Table 1. <br /> The basin testing included three phases, as indicated on the schedule: saturation, constant head testing, <br /> and falling head testing. Each phase is described below. <br /> 2.3.1 Saturation <br /> The soils at each basin were saturated before,testing began. This Was done by supplying water to each <br /> basin for a 24-hour period. Flow into each basin was sustained at a rate that would keep a generally <br /> constant level of water in the test basin, although the exact level was.not a factor. Prior to leaving the site for <br /> the day, it was possible to adjust the flow.,into the basins to a rate that kept water in the basins overnight at a <br /> relatively constant head. <br /> 2.3.2 Constant Head Test <br /> The constant head tests; were <br /> performed.. first. The test was <br /> started after the basins had been. <br /> saturated for approximately 24" <br /> hours. The constant head test was <br /> performed by documenting the <br /> water level in the basin and: <br /> supplying enough flow to maintain . <br /> this level over the course of an <br /> eight hour test period. In the early <br /> stages of the test, the flow rate had <br /> to be adjusted periodically to keep <br /> the water level in the basin <br /> constant. During the test, the water Constant head test in progress <br /> level was recorded, the flow rate <br /> was measured, and the <br /> 3 <br />