Laserfiche WebLink
' Appendix B <br /> i EXPLORATORY BORING AND <br /> WELL INSTALLATION PROCEDURES <br /> ' Theeneral procedures used in site assessments for drilling exploratory borings, <br /> 9 <br /> collecting samples, and installing monitoring wells are described in this appendix <br /> ' These general procedures are used to provide consistent and reproducible results, <br /> however, conditions may exist where variations of these procedures are applicable <br /> The following procedures are supervised by a California State-registered geologist <br /> ' or civil engineer <br /> ' Exploratory Soil Borings <br /> Exploratory soil borings for sites characterized by relatively shallow (less than 100 <br /> feet deep) groundwater may be drilled using 6- to 8-inch-diameter, continuous- <br /> flight, hollow-stem auger drilling equipment or direct push technology(DPT) such as <br /> a Geoprobe® The drilling method for sites in which depth to groundwater is <br /> greater than 100 feet is determined on a case-by-case basis Soil samples for <br /> logging will be obtained from auger-retum materials and by advancing a modified <br /> California split-spoon sampler equipped with brass or stainless steel linr into <br /> undisturbed soil beyond the tip of the auger Soils will be logged by a geolt ist or <br /> civil engineer according to the United Soil Classification System and standard <br /> geological techniques Exploratory soil borings not used for monitoring well <br /> installation will be backfilled to the surface with a bentonite cement slung pumped <br /> into the boring through a tremae pipe <br /> ' The soil sampling equipment will be cleaned with a detergent water solution, rinsed <br /> with clean water, and equipped with clean liners between sampling intervals <br /> Augers and samplers will be steam cleaned or washed in a tri-sodium phosphate <br /> solution and rinsed with clean water between each boring to reduce the possibility <br /> of cross contamination Cleaning effluent will be contained in DOT approved 55- <br /> gallon drums and temporarily stored on site The disposal of the effluent will be the <br /> ' responsibility of Western Oil and Spreading, Inc <br /> Drill cuttings generated during the drilling procedure will be stockpiled on site <br /> ' Stockpiled drill cuttings will be placed on and covered with six-mill plastic sheeting <br /> The stockpiled soil is typically characterized by collecting and analyzing composite <br /> samples from the stockpile D K Barber P E & Associates will recommend an <br /> i B - 1 <br />