Laserfiche WebLink
r <br /> i <br /> a <br /> IM <br /> k <br /> 4.3 FIELD PROCEDURES <br /> 4.3.1 SOIL BORINGS AND MONITORING WELL INSTALLATION <br /> Soil borings will be drilled and sampled using 8-inch-outside diameter (OD), 3-inch- <br /> inside diameter (ID) hollow-stem augers. Soil borings will be sampled at five-foot <br /> intervals during boring advancement to produce lithologic logs. Drill cuttings will be <br /> disposed as described in Section 3. Samples will be collected using a 2-inch ID split- <br /> spoon sampler lined with brass sleeves. Each sleeve will be capped with Teflon tape <br /> and a polyethylene cap, taped to the sleeve. Sample identification numbers will be <br /> marked on the outside of the sleeve using indelible markers• t rte ( us17 $^ <br /> The well will be installed through 12-inch OD, 8-inch ID hollow-stem augers. If <br /> unfavorable conditions (sand locking, heaving,and,etc.) prevent or impede completion <br /> of the well using hollow-stem augers,air- or mud-rotary drilling may be used to prepare <br /> a borehole for well installation. <br /> ' <br /> The well casing and screen will be a 4-inch ID flush-threaded, Schedule 40, PVC. The <br /> screen section will be factory slotted with 0.02-inch slots. The annulus around the <br /> screen will be filled with No. 3 sand (Lonest a%mum screened Term nit ri g well <br /> llThe <br /> be screened across the water table with a m <br /> exact interval to be screened will be determined in the field, based on the first <br /> d the first water-bearing permeable zone <br /> appearance of water in the boring an <br /> encountered. <br /> The well installation procedures are as follows: <br /> The proposed boring locations will be marked with stakes and cleared for <br /> utilities. <br /> . The drill rig, drilling equipment, and brass sleeves will be decontaminate <br /> by steam cleaning or by detergent/water/isopropanol/de-ionized water <br /> washings before and after drilling. <br /> . The drill cuttings and split spoon samples will be logged by a CH2M <br /> HILL hydrogeologist or geologist. <br /> The mor.=taring well will be screened across the water table. The screen <br /> length will extend approximately 5 feet above and 15 feet below the <br /> water table. <br /> Schedule 40 PVC casing and the well screen will be installed through the <br /> hollow stern augers. A threaded PVC bottom cap will be placed below <br /> the screen. <br /> __.. ...... . ... . ..... .. _ ...... <br /> SF031605CNF1004.51 <br /> 4-4 <br />