Tank S-102 Waste Spill

Shirley OlingerManager

Jerry LongChief Operating Officer

safety performance cleanup closure

ME Environmental ManagementEnvironmental Management

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S-102 Spill Area – Friday, July 27, 2007About 85 gallons of mixed tank waste spilled

S-102 Detail

Not Shown to Scale

Ground Level

Pump Inlet

12” Riser

Tank Bottom

Tank Waste

Pump Motor

Pump Riser Extension Box (1)

Dilution Water Hose In-Box (1b)

Hose-in-Hose Transfer Line (1a)

37’

75’

Sparge Water Hose In-Box (1c)

Cover Block

Sparge Water Hose Outside Box (3)

Relief Valve

Leak Detector

Dilution Water Hose Outside Box (2)

Pit Drain

Pump Seal (1d)

Potential Spill Sources

1.Pump Riser Extension Box or Transfer Pit

a) Transfer Lineb) Dilution Water Hose In-

Boxc) Sparge Water Hose In-

Boxd) Pump Motor Seal

2.Sparge Water Hose Outside Box

3.Dilution Water Hose Outside Box

Transfer Pit

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With the pump suction “strainer plate” within ½ - 1” from the tank floor, the high density waste heel was sufficient to block the free flow of relatively low density (Specific Gravity of about 1.1) of transfer waste during reverse rotation and subsequently pressurized the suction cavity of the pump, forcing water up the dilution line and/or sparge line.

Tank Bottom

Dilution LineDischarge

Bottom and Side-View Photo of Pump Inlet

Flow Path

18 in.

Hard Waste Heel

ReverseRotationBegins

DilutedWasteFlows Downto Inlet Ring

~½-inch Tall by 5-9/32-inch Diameter

Flow Path is Blocked along with Sparge LinesForcing Waste Up

Dilution Line

Sparge LineDischarge

Scenario

* Reverse rotation for 105 seconds @ 45Hz was performed 3 times

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S-102 Event Summary – Dilution Hose Source of Spill

• Spill occurred between 2:05 a.m. and 2:20 a.m. while pump was operated in reverse direction

– No personnel in the tank farm– Abnormal radiation dose rate readings identified at 2:20 a.m.

• Splash pattern consistent with release near dilution hose at NW corner of pump pit

• Spill pool consistent with near surface release– Bathtub ring along north side of pump pit between pit and dilution hose– No discoloration near potential release points from pit or pump box

• Transfer pit and pump riser extension box unlikely sources of spill– Pump box drains into transfer pit OR into the tank– Leak detector in transfer pit– Transfer pit drains to tank– Transfer pit is below grade with a void volume of over 1,500 gallons

• Drainage collected from dilution hose resulted in high dose rates confirming waste was in dilution hose

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S-102 Event Investigations

• Several Investigations – DOE/ORP Reviews

• DOE Type A – Complete 09/19/07• DOE EM-60 – Complete 09/27/07• DOE/ORP Reviews:

– ORP Response – Complete 8/29/07– HPI – Complete 10/23/07– Assessment of ORP Management Systems – Complete 11/09/07

– CH2M HILL Internal Investigation• Event Investigation/Root Cause Analysis – Completed 9/17/07• Emergency Response Investigation – Completed 8/27/07• Health Effects Investigation – Completed 10/4/07• Engineering Design Program Review – Completed 10/9/07

• Direct Cause: Over-pressurization and rupture of the dilution water supply hose as a result of a plugged pump suction during reverse pump operation

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Root Causes:

• Engineering Design Less than Adequate

• Change Control Process Less than Adequate

• Tank Farm Lighting Less than Adequate

• Abnormal Operating Procedures Less than Adequate

• Training Less than Adequate

• Formality of Operations Less than Adequate

• Radiological Controls Survey Techniques Less than Adequate

CH2M HILL Root Cause and Contributors by ISMS Core Functions

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S-102 Corrective Actions

• Comprehensive Corrective Action Plan– Type A - Justification of Needs (JONs)– CH2M HILL Investigation Findings – EM-60 Input– DOE ORP Internal Reviews

• Coordination of CAP Critical– 2 Field Offices: ORP and RL– 3 Contractors

• CH2M HILL – Event Owner• Fluor Hanford – Emergency Management• Advance Medicine Hanford – Medical

Evaluations/Communication

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S-102 Corrective Actions (cont.)

• Focus areas of CAP for ORP– Engineering and Quality Oversight

• Heavily focused on Authorization Basis document review and approval and SSO oversight

• Need for increased oversight of process/system engineering recognized• Need for internal assessments of ORP

– Conduct of Operations• Although routine operations observed, emphasis has been on known higher risk/higher

consequence evolutions• Increase oversight of more routine operational activities, including backshift operations

(i.e., tank retrieval operations)• Heighten alertness when activities not occurring as planned (pump stuck or need for

reverse operation)

– Radiological and Industrial Hygiene Coverage• Programmatic reviews conducted• Improve field operations coverage • Factor in lessons learned

– ORP Response/Human Factors Investigations• Strengthen the DOE Facility Representative’s ability to properly respond to abnormal

and emergency events

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CH2M HILL Corrective Actions

• Engineering – Improve engineering design review and hazards analysis/evaluation process– Review strategies for controlling waste leaks – prevention instead of mitigation

• Management System– Analyze, develop and deliver conduct of operations training– Review effectiveness of causal analyses and corrective actions for significant

events since January 1, 2003– Strengthen management oversight plans for waste retrieval activities– Refine work control process

• Safety and Health – Ensure potentially exposed personnel are examined and documented by on-site

medical provider– Develop consistent notifications to patients regarding test results– Strengthen post-exposure medical monitoring process– Continue medical monitoring and surveillance of potentially affected workers

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CH2M HILL Corrective Actions (cont.)

• Emergency Management– Evaluate low consequence, high probability hazards for emergency response– Evaluate technologies for identifying small waste leaks– Revise/clarify procedures for activating response teams for non-emergency

events• Work Control

– Eliminate use of verbal work packages for activities comparable to manual pump rotation which required application of specific torque limits provided by vendor

• Industrial Hygiene– Implement methods for continuous monitoring of vapors during waste transfers– Integrate Industrial Hygiene response to abnormal events that may involve

chemical release into abnormal response procedures. Sampling requirements should be specified

• Radiological Protection– Clarify radiological monitoring requirements associated with TSR and leak

detection

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CH2M HILL Lessons Learned

• “Worst-to-Best” DOE Complex Safety Statistics– From 2005 to 2007:

• Total Recordables dropped 71%• DART Rates dropped 82%• Lost Workday Case Rate dropped 61%• Stop Work process dramatically dropped 100%• Occurrence Reports dropped 71%• Skin and Clothing Contamination Reports (ORPS Reportables) dropped 100%• Employee Concerns dropped by 62%

Trend data indicated safe operations . . .

• 2007 America’s Safest Companies

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Lessons Learned

• CH2M HILL– Engineering Design / Hazards Analysis

• Formalize design review process and evaluate some total of all modifications.

– Conduct of Operations• Complacency: lighting, notifications, radiation

readings, etc.– More focus on ConOps training and implementation.

– Emergency Response• Drills: practice is important• Focus on chemical hazards as well as radiological

hazards

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Lessons Learned

• Good safety performance metrics can give a false sense of security– Key performance indicators – TRC/DART, Radiological, TSR, Electrical Safety, ORPs,

PERs, etc.– ISMS performance measures– Safety culture indicators – VPP, Safe Work Environment personnel survey results,

Hanford Concerns Council– Reduction in employee concerns

• ORP assessments – more is not necessarily better– ORP completed 38 assessments of the TFC in FY2007– Facility Representative oversight of retrieval operations: no procedure compliance

problems– Quarterly Assessment Program evaluations, Quarterly recurring events evaluations did

not indicate negative trend in operational performance – Facility Representative observations of S-102 retrieval operations 1 and 2 days prior to

the event indicated good conduct of operations• Past successes do not guarantee future success

– Successfully completed 7 tank retrievals– Successfully deployed similar retrieval system at tank S-112

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Lessons Learned (cont.)

• Hind-sight indicators provide vital information– Several contractor lay-offs due to funding cuts– Contractor senior manager for Closure Operations

distracted due to medical and other reasons– S Tank Farm housekeeping less than adequate– Vacant position for Retrieval FPD, rad engineer, industrial

hygiene for several months– Inadequate DOE oversight of contractor engineering

programs – Not enough FTE’s to oversee 2 major projects

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Next Steps

• Issue Independent ORP Oversight Assessment Report and develop Corrective Actions

• EM-1 Approve Type A CAP

• Complete ISMS Declaration

• Conduct Contractor Readiness Assessment to resume retrieval of tank C-109; ORP Manager start-up approval authority