DEVELOPMENT OF PENETRATION ENHANCEMENT FOR THE CONE PENETROMETER USING SONIC DRILLING TECHNOLOGY

IN THIS PROJECT, THE FEASIBILITY OF COMBINING SONIC DRILLING AND CONE PENETRATION TECHNOLOGIES WILL BE EVALUATED AND A SET OF PRELIMINARY DESIGN DRAWINGS DEVELOPED. SONIC DRILLING TECHNOLOGY HAS RECENTLY BEEN DEMONSTRATED AT THE HANFORD SITE, WA. THE RESULTS OF THE DEMONSTRATION PROVED THAT SMALL DIAMETER MONITORING WELLS COULD BE INSTALLED TO THE DESIRED DEPTH IN A RAPID MANNER USING THIS TECHNOLOGY. PRODUCTION RATES WERE NEARLY DOUBLE THOSE OF THE STANDARD CABLE TOOL METHODS USED, WHICH RESULTED IN A SIGNIFICANT COST SAVINGS. CONE PENETRATION TECHNOLOGY (CPT) HAS HAD LIMITED SUCCESS IN PENETRATING THE GRAVEL FORMATION OF THE HANFORD SITE. AT AREAS WHERE THE CPT HAS BEEN ABLE TO PENETRATE, A SIGNIFICANT COST SAVING HAS BEEN REALIZED. TYPICAL COSTS FOR THE CPT AT HANFORD ARE $65/FT COMPARED TO $800/FT FOR CABLE TOOL DRILLING. GIVEN THE NUMBER OF INVESTIGATION AND MONITORING WELLS REQUIRED AT THE HANFORD AND OTHER DOE SITES, SAVINGS OF TENS OF MILLIONS OF DOLLARS WILL BE REALIZED USING THE SONIC-CPT METHOD. BY DEVELOPING THIS TECHNOLOGY, THE UTILITY OF THE CPT CAN BE EXTENDED TO DEEPER DEPTHS AND MORE LOCATIONS AT BOTH HANFORD AND OTHER DOE SITES. IN ADDITION, THE DEVELOPMENT OF LARGER PROBES AND SENSORS WILL REQUIRE THIS TECHNOLOGY TO REACH THE DEPTHS OF CURRENT CPT SIZED PROBES. THE END RESULT OF PHASE I WILL BE A SET OF DESIGN DRAWINGS WHICH CAN BE USED TO FABRICATE A PROTOTYPE FOR EVALUATION IN PHASE II.