Allan F. Pardini

Independent Review of Tank 241-AY-101 Fitness for Service

Video inspections in the annulus of Hanford double-shell waste storage tank 241-AY-101 in 2001 and earlier showed rust over large areas of the primary and secondary tank walls. These observations led to extensive on-destructive inspections and analyses to determine the extent and severity of the corrosion and correction of several operational deficiencies that contributed to the problem. PNNL has performed an independent review of the accumulated evidence from these efforts to determine whether unacceptable conditions were corrected and the current condition of the tank meets or exceeds technical and operational requirements. The findings of this review are the subject of this report. The conclusion is that AY-101 is fit for service without restriction subject to several recommendations for further inspections and analyses.

Ultrasonic Examination of Double-Shell Tank 241-AY-101. Examination completed October 2007

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-AY-102. PNNL is responsible for preparing a report(s) that describes the results of the AREVA ultrasonic examinations.

Ultrasonic Examination of Double-Shell Tank 241-AN-107. Examination Completed March 2007

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-AN-107. 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 tank. The requirements for the ultrasonic examination of Tank 241-AN-107 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. 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-AN-107 have been evaluated by PNNL personnel. The 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, the upper portion of the knuckle region, four small areas of the lower portion of the knuckle region within the air slot entrances, and the lower portion of the knuckle utilizing a multiple V path technique qualified for the extended Y-arm scanner from Riser 26. The examination also included two vertical 15-in.-wide scan paths over the entire height of the tank from Riser 25. The examination was performed to detect any wall thinning, pitting, or cracking in the primary tank wall.

Ultrasonic Examination of Double-Shell Tank 241-AN-106. Completed June 2007

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-AN-106. PNNL is responsible for preparing a report(s) that describes the results of the AREVA ultrasonic examinations.

Ultrasonic Examination of Double-Shell Tank 241-AN-103 Examination Completed October 2005

COGEMA Engineering Corporation (COGEMA), under a contract from CH2M Hill Hanford Group (CH2M Hill), has performed an ultrasonic examination of selected portions of Double-Shell Tank 241-AN-103. PNNL is responsible for preparing a report(s) that describes the results of the COGEMA ultrasonic examinations.

Ultrasonic Examination of Double-Shell Tank 241-AP-104. February 2005

COGEMA Engineering Corporation (COGEMA), under a contract from CH2M Hill Hanford Group (CH2M Hill), has performed an ultrasonic nondestructive examination of selected portions of Double-Shell Tank 241-AP-104. 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-AP-104 were to detect, characterize (identify, size, and locate), and record measurements made of any wall thinning that might be present in the wall of the primary tank in the upper knuckle region, and any wall thinning, pitting, or cracks in the wall of the secondary tank in the lower knuckle region. Any measurements that exceed the requirements set forth in the Engineering Task Plan (ETP), RPP-22571 (Jensen 2004) and summarized on page 1 of this document, are 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 disk and paper copies of all measurements are provided to PNNL for third-party evaluation. PNNL is responsible for preparing a report that describes the results of the COGEMA ultrasonic examinations.

Ultrasonic Examination of Double-Shell Tank 241-AP-102. February 2005

COGEMA Engineering Corporation (COGEMA), under a contract from CH2M Hill Hanford Group (CH2M Hill), has performed an ultrasonic nondestructive examination of selected portions of Double-Shell Tank 241-AP-102. The purpose of this examination was to provide information that could be used to evaluate the integrity of the wall of the primary tank. The requirements for the ultrasonic examination of Tank 241-AP-102 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. Any measurements that exceed the requirements set forth in the Engineering Task Plan (ETP), RPP-22571 (Jensen 2004) and summarized on page 1 of this document, are 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 disk and paper copies of all measurements are provided to PNNL for third-party evaluation. PNNL is responsible for preparing a report that describes the results of the COGEMA ultrasonic examinations.

Ultrasonic Examination of Double-Shell Tank 241-AN-104. Examination Completed August 2005

COGEMA Engineering Corporation (COGEMA), under a contract from CH2M Hill Hanford Group (CH2M Hill), has performed an ultrasonic examination of selected portions of Double-Shell Tank 241-AN-104. PNNL is responsible for preparing a report(s) that describes the results of the COGEMA ultrasonic examinations.

Ultrasonic Examination of Double-Shell Tank 214-AN-101

COEGMA Engineering Corporation (COGEMA) under a contract from CH2M Hill Hanford Group (CH2M Hill) has performed an ultrasonic examination of selected portions of Double-Shell Tank 241-AN-101. PNNL is responsible for preparing a report(s) that describes the results of the COGEMs ultrasonic examinations.

Ultrasonic Examination of Double-Shell Tank 241-SY-101. Examination Completed March 2004.

COGEMA Engineering Corporation (COGEMA), under a contract from CH2M Hill Hanford Group (CH2M Hill), has performed an ultrasonic nondestructive examination of selected portions of Double-Shell Tank 241-SY-101. The purpose of this examination was to provide information that could be used to evaluate the integrity of the wall of the primary tank. The requirements for the ultrasonic examination of Tank 241-SY-101 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. Any measurements that exceed the requirements set forth in the Engineering Task Plan (ETP), RPP-17750 (Jensen 2003) and summarized on page 1 of this document, are 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 disk and paper copies of all measurements are provided to PNNL for third-party evaluation. PNNL is responsible for preparing a report that describes the results of the COGEMA ultrasonic examinations.