Using UCS as a surrogate performance standard at the NCSUNPL Site

摘要

Treated hazardous material at the North Carolina State University (NCSU) Lot 86 National Priorities List (NPL) Site was evaluated using unconfined compressive strength (UCS) as a surrogate performance standard for the toxicity characteristic leaching procedure (TCLP). During a preconstruction treatability study, UCS test results were related to the TCLP performance standards as stipulated in the record of decision. During construction, 113 UCS samples were obtained and test results indicated that over 8,410 m(3) (11,000 yd(3)) of pre-RCRA (Resource Conservation and Recovery Act) chemical waste generated from the University's educational and research laboratories had been successfully stabilized. Using a crane-mounted mixing unit for a portion of the stabilization operations, and a trackhoe unit for the remainder of the construction, 2.03 Gg (2,240 t) of cement and 2.81 ML (743,000 gal.) of water were mixed with impacted soil and waste material resulting in a 3 m (10 ft) thick encapsulated monolith half the size of a football field.