Ultrasonic Examination of Double-Shell Tank 241-AW-103. Examination Completed September 2006

Abstract

AREVA NC Inc. (AREVA), under a contract from CH2M Hill Hanford Group (CH2M Hill), has performed an ultrasonic examination of selected portions of Double-Shell Tank 241-AW-103. PNNL is responsible for preparing a report(s) that describes the results of the AREVA ultrasonic examinations. The purpose of this examination was to provide information that could be used to evaluate the integrity of the wall of the primary and secondary tank. The requirements for the ultrasonic examination of Tank 241-AW-103 were to detect, characterize (identify, size, and locate), and record measurements made of any wall thinning, pitting, or cracks that might be present in the wall of the primary tank and the wall of the secondary tank. Any measurements that exceed the requirements set forth in the Engineering Task Plan (ETP), RPP-Plan-27202 (Jensen 2005) and summarized on page 1 of this document, are to be reported to CH2M Hill and the Pacific Northwest National Laboratory (PNNL) for further evaluation. Under the contract with CH2M Hill, all data is to be recorded on electronic media and paper copies of all measurements are provided to PNNL for third-party evaluation. PNNL is responsible for preparing a report(s) that describes the results of the AREVA ultrasonic examinations. The results of the examination of Tank 241-AW-103 have been evaluated by PNNL personnel. The primary tank ultrasonic examination consisted of two vertical 15-in.-wide scan paths over the entire height of the tank, the heat-affected zone (HAZ) of four vertical welds and one horizontal weld from Riser 29 and two vertical 15-in.-wide scan paths over the entire height of the tank from Riser 28. Additionally, two vertical 15-in.-wide scan paths over the entire height of the secondary tank from Riser 28 were performed. The examinations were performed to detect any wall thinning, pitting, or cracking in the primary tank wall.