Agenda - Council - 12/20/1983 - Laserfiche WebLink

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I I I I I I I I I i I I I I I ! I ! Wells less than fifty (50) feet in depth and not encountering at least ten (10) feet of impervious material . . .150 ft. Any water supply well or buried water suction pipe . .75 ft. Buildings ...................... 20 ft. Property lines and buried pipe distribution water under pressure ...................... ilo ft. Other seepage pits .................. 3 times the diameter of the largest pit (edge to edge). Effective soil treatment area of a seepage pit shall be calculated as the sidewall area below the inlet, exclusive of any hardpan, rock, or clay formations. The sidewall area shall be based on the outer diameter of the pit lining plus twelve (12) inches of rock in the annular space. Required treatment area shall be determined by the percolation test described ~n Chapter 150.014A and from using the column for seepage beds in Table 4-1. In no case shall a seepage pit be installed in soils where the percolation rate of any stratum is faster than one-half (1/2) minute per inch (coarse sand). A percolation test shall be made in each vertical stratum penetrated by the seepage pit, and the weighted average of the results, exclusive of results from soil strata in which the percolation rate is slower than thirty (30) minutes per inch, shall be computed and applied~to the seepage bed column of Table 4-1 as indicated. 1. A minimum of four (4) feet composite depth of porous formation for each installation shall be provided in one (1) or more pits. 2. Ail pits shall have an inside diameter of at least five (5) feet. Construction of all seepage pits shall conform to the following requi~e- men ts: 1. To prevent cave-in, the pit shall be precast concrete or lined with brick, stone, or block at least four (4) inches thick, laid in a radial arch to support the pit walls. 2. The brick, stone, or block shall be laid watertight above the inlet and with open joints below the inlet to provide adequate passage of liquids. 3. A minimum annular space of twelve (12) inches between the pit lining and excavation wall shall be filled with crushed rock or gravel. 4. The seepage pit shall be so const~'ucted at the top as to be capable of supporting the overburden of earth and any reasonable load to which it is subjected. Access to the pit shall be provided by means of a manhole or inspection hole equipped wirh a watertfght cover. The seepage pit may terminate in a cc~nventional manhole top, frame and cover, but if a manhole is used, ~t shall exten~ through the earth