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'k+ #M vl rn l@ CAMBRIA STANDARD FIELD PROCEDURES FOR CONE PENETROMETER TESTING This document describes Cambria Environmental Technology's standard field methods for Cone Penetrometer Testing (CPT) These procedures are designed to comply with Federal, State and local regulatory guidelines Specific field procedures are summarized below Cone Penetrometer Testing (CPT) Cone Penetrometer Testing is performed by a trained geologist or engineer working under the supervision of a California Registered Geologist(RG)or a Certified Engineering Geologist(CEG) Cone Penetrometer Tests(CPT)are carried out by pushing an integrated electronic piezocone into the subsurface The piezocone is pushed using a specially designed CPT rig with a force capacity of 20 to 25 tons The piezoconcs are capable of recording the following parameters Tip Resistance(Qc) Sleeve Friction(Fs) Pore Water Pressure(U) Bulk Soil Resistivity(rho)- with an added module A compression cone is used for each CPT sounding Piezocones with rated load capacities of 5, 10 or 20 tons are used depending on soil conditions The 5 and 10 ton cones have a tip area of 10 sq cm and a friction sleeve area of 150 sq cm The 20 ton cones have a tip area of 15 sq cm and a friction sleeve area of 250 sq cm A pore water pressure filter is located directly behind the cone tip Each of the filters is saturated in glycerin under vacuum pressure prior to penetration Pore Pressure Dissipation Tests(PPDT)are recorded • at 5 second intervals during pauses in penetration The equilibrium pore water pressure from the dissipation test can be used to identify the depth to groundwater The measured parameters are printed simultaneously on a printer and stored on a computer disk for future analysis All CPTs are carried out in accordance with ASTM D-3441 A complete set of baseline readings is taken prior to each sounding to determine any zero load offsets The inferred stratigraphic profile at each CPT location is included on the plotted CPT logs The strati graphic interpretations are based on relationships between cone bearing (Qc) and friction ratio (Rf) The friction ratio is a calculated parameter(Fs/Qc) used in conjunction with the cone bearing to identify the soil type Generally, soft cohesive soils have low cone bearing pressures and high friction ratios Cohesionless soils (sands) have high cone bearing pressures and low friction ratios The classification of soils is based on correlations developed by Robertson et al (1986) It is not always possible to clearly identify a soil type based on Qc and Rf alone Correlation with existing soils information and analysis of pore water pressure measurements should also be used in determining soil type CPT and sampling equipment are steam-cleaned or washed prior to work and between borings to prevent cross-contamination Sampling equipment is washed between samples with trisodium phosphate or an equivalent EPA-approved detergent Groundwater samples are decanted into appropriate containers supplied by the analytic laboratory Samples are labeled, placed in protective foam sleeves, stored on crushed ice at or below 4°C,and transported under chain-of-custody to the laboratory The CPT borings are filled to the ground surface with cement grout poured or pumped through a tremie pipe F \TEMPLATE\SOPS\C PT WPD