Laserfiche WebLink
SOP No. 5.0 Monitoring Well Installation <br />wells, additional centralizers will be attached to the riser casing at 100 foot intervals and one <br />near the top of the well string. <br />The Field Geologist will calculate and record the volume of the filter pack, bentonite seal, and <br />grout required to fill the annular space based on the borehole size and casing size. The volume is <br />calculated by subtracting the volume of the casing (based on the outer diameter) from the volume <br />of the borehole using the equation: <br />V=,7 (rb22 <br />-r,) h <br />where: <br />V = volume (in feet) <br />rb = radius of borehole (in feet) <br />rc = radius of casing (in feet) <br />h = height (in feet) between the top and bottom of the material (filter pack, <br />bentonite, or grout). <br />R = p' (3.14) <br />Measurements made during filling of the annular space will be performed to the nearest 0.1 foot <br />below ground surface (bgs) and will consist of the following: <br />• Total depth of borehole at the completion of drilling <br />• Total depth of the open borehole before the start of well construction <br />• Lengths of the end cap, screen sections, riser blank sections, and stickup of well above <br />ground surface <br />• The depth to the top of the filter pack, top of the bentonite seal, and the top of each grout lift <br />Following well completion, the horizontal location of the monitoring well will be surveyed in <br />accordance with SOP 34.0, Surveying (GPS). The elevation of the ground surface and top of the <br />PVC casing (i.e., water level measuring point) will also be determined. A notch will be cut on <br />the north side of the PVC casing that will be used as a measuring point for water levels. <br />5.2.1.1 Casing and Screen Requirements <br />The casing requirements will be as follows (EPA 1990): <br />• All casing will be new, unused, and decontaminated according to the specifications of <br />Section 5.1. <br />All PVC will conform to the ASTM Standard F-480-88A or the National Sanitation <br />Foundation Standard 14 (Plastic Pipe System). <br />• The casing will be straight and plumb. <br />Well screen requirements include: <br />7/28/08 Page 4 of 6 R Squared Inc. <br />Attachment A