Final report of the TWRS Plant Implementation Team to review potential reactive component in tank 241-T-111 and methane in tank 241-SY-101 gas release event

This is the final report of the results of a Tank Waste Remediation Systems Plant Implementation Team chartered by TWRS Operations, in response to a potential Unreviewed Safety Question (USQ) due to the discovery of a reactive component in waste tank 241-T-111 (T-111). Tank T-111, a non-Watch List single-shell tank, has no historical evidence of any potential safety problems. Core samples from tank T-111 were taken in 1991 and analyzed in 1992. The presence of uncharacterized exotherms was identified in the first three segments of two cores and reported to tank farm management in November 1993