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<br />' I.0 INTRODUCTION <br />This report presents the data collected during an in situ soil investigation carried out at the Battle <br />Mountain Resources San Luis Mine tailings facility between the dates of April 27, 1995 and May 4, <br />' 1995. The work was performed under the direction of Steffen Robertson and Kirsten; Inc. It is our <br />understanding that all test holes were located by Steffen Robertson and Kirsten, Inc. and surveyed <br />by Battle Mountain Resources. The investigation utilized energy calibrated standard penetration <br />testing (SPT) and cone penetrometer testing (CPT) which included the measurement of downhole <br />seismic shear wave velocity. A total of 3 SPT borings and 16 CPTs were conducted at the site, and <br />all 16 CPTs were pushed urnil the drill rig reached refusal. In addition, downhole shear wave <br />' velocities were measured at all of the locations. This report descnbes the methods used to collect <br />the data and presents a summary of the data in the appendixes which follow. <br />' 2.0 FIELD EQUIPMENT AND PROCEDURES <br />2.1 Electric Cone Testing <br />The cone penetration tests (CPTs) were carried out by ConeTec, Inc. of Denver, Colonado, using an <br />integrated electronic cone system. A 10-ton compression cone built by Adara Systems was used for <br />all of the soundings. This cone has a tip area of 10 sq. cm, and friction sleeve area of 150 sq. cm. A <br />piezometer element 6 mm thick is located immediately behind the cone tip. The compression cone <br />is designed with an equal end area friction sleeve and a tip end area ratio of 0.85. The cone system <br />used during the program was capable of recording the following parameters at 5 cm. depth intervals: <br />. - Tip Resistance (Qc) <br />' . - Sleeve Friction (Fs) <br />- Dynamic Pore Pressure (Ut) <br />The cone and accompanying seismic data acquisition systems also recorded shear (S) wave arrival <br />times at 1 m increments. The above parameters, excluding the shear wave velocities were printed <br />' simultaneously on a printer and stored on digital media for future analysis and reference. <br />The porous plastic pore pressure element was located directly behind the cone tip. Each of the <br />' elements were saturated in glycerin under vacuum pressure prior to penetration. Piore pressure <br />dissipations were recorded at 5 second intervals when appropriate during pauses in the penetration. <br />' A complete set of baseline readings were taken prior to each sounding to determine temperature shifts <br />and any zero load offsets. Establishing temperature shifts and load offsets enables the engineer to <br />make cotrections to the cone data where necessary. These corrections are critical, especially where <br />' the load conditions are relarively low, and generally are the single largest source of error with respect <br />to the accuracy of cone data. <br />' The cone was pushed using a CME 75 drill rig, having a down presswe capacity of approximately <br />5 tons. The cone testing rig was supplied and operated by Layne Environmental of Denver, Colorado. <br />Cor+eTEC, INC. 1 Drnver. Colorado <br />1 <br />