October 14, 2010 

Mr. Robert M. Shaw 

Project Manager, Tank Farm Closure Project 

U.S. Department of Energy, Idaho Operations Office 

MS 1222 

1955 Freemont Avenue 

Idaho Falls, ID 83415 

SUBJECT: U.S. NUCLEAR REGULATORY COMMISSION ONSITE OBSERVATION 

REPORT FOR THE IDAHO NATIONAL LABORATORY IDAHO NUCLEAR 

TECHNOLOGY AND ENGINEERING CENTER TANK FARM FACILITY 

Dear Mr. Shaw: 

The enclosed document describes the U.S. Nuclear Regulatory Commission’s (NRC’s) onsite 

observation activities on August 10, 2010, for monitoring disposal actions taken by the 

U.S. Department of Energy (DOE) at the Idaho National Laboratory (INL), Idaho Nuclear 

Technology and Engineering Center Tank Farm Facility (INTEC TFF). This onsite observation 

was conducted in accordance with the Ronald Reagan National Defense Authorization Act for 

Fiscal Year 2005 (NDAA), which requires NRC to monitor disposal actions taken by the DOE for 

the purpose of assessing compliance with the performance objectives set out in Subpart C of 

Part 61 of Title 10 of the Code of Federal Regulations. 

NRC’s onsite observation at INL was primarily focused on the performance objective 10 CFR 

61.43. The main focus was to verify DOE’s radiation protection and environmental monitoring 

programs at the INTEC TFF. Because environmental monitoring data provides information to 

assess performance assessment models, this onsite observation also partially addresses the 

10 CFR 61.41 performance objectives. Additional visits will be conducted in the future to 

assess compliance with these and other performance objectives in 10 CFR Part 61, Subpart C. 

If you have any questions or need additional information regarding this report, please call me at 

301-415-7319, or call Maurice Heath, Project Manager of my staff, at 301-415-3137. 

 Sincerely, 

 /RA/ G.Suber for D. Skeen 

 David Skeen, Deputy Director 

 Environmental Protection and Performance 

 Assessment Directorate 

 Division of Waste Management 

 and Environmental Protection 

 Office of Federal and State Materials 

 and Environmental Management Programs 

Enclosure: NRC Observation Report
Mr. Robert M. Shaw 

Project Manager, Tank Farm Closure Project 

U.S. Department of Energy, Idaho Operations Office 

MS 1222 

1955 Freemont Avenue 

Idaho Falls, ID 83415 

SUBJECT: U.S. NUCLEAR REGULATORY COMMISSION ONSITE OBSERVATION 

REPORT FOR THE IDAHO NATIONAL LABORATORY IDAHO NUCLEAR 

TECHNOLOGY AND ENGINEERING CENTER TANK FARM FACILITY 

Dear Mr. Shaw: 

The enclosed document describes the U.S. Nuclear Regulatory Commission’s (NRC’s) onsite 

observation activities on August 10, 2010, for monitoring disposal actions taken by the 

U.S. Department of Energy (DOE) at the Idaho National Laboratory (INL), Idaho Nuclear 

Technology and Engineering Center Tank Farm Facility (INTEC TFF). This onsite observation 

was conducted in accordance with the Ronald Reagan National Defense Authorization Act for 

Fiscal Year 2005 (NDAA), which requires NRC to monitor disposal actions taken by the DOE for 

the purpose of assessing compliance with the performance objectives set out in Subpart C of 

Part 61 of Title 10 of the Code of Federal Regulations. 

NRC’s onsite observation at INL was primarily focused on the performance objective 10 CFR 

61.43. The main focus was to verify DOE’s radiation protection and environmental monitoring 

programs at the INTEC TFF. Because environmental monitoring data provides information to 

assess performance assessment models, this onsite observation also partially addresses the 

10 CFR 61.41 performance objectives. Additional visits will be conducted in the future to 

assess compliance with these and other performance objectives in 10 CFR Part 61, Subpart C. 

If you have any questions or need additional information regarding this report, please call me at 

301-415-7319, or call Maurice Heath, Project Manager of my staff, at 301-415-3137. 

Sincerely, 

David Skeen, Deputy Director 

Environmental Protection and Performance 

 Assessment Directorate 

Division of Waste Management 

 and Environmental Protection 

Office of Federal and State Materials 

 and Environmental Management Programs 

Enclosure: NRC Observation Report 

ML102770022

OFC DWMEP LA DWMEP LA DWMEP DWMEP DWMEP 

NAME MHeath TMoon by 

Email 

CBarr AWalker-Smith CMcKenney GSuber GSuber for 

DSkeen 

DATE 10/4/10 10/4/10 / /10 10/6/10 10/8/10 10/8/10 10/14/10 

OFFICIAL RECORD COPY
Enclosure 

IDAHO NATIONAL LABORATORY IDAHO NUCLEAR TECHNOLOGY AND ENGINEERING 

CENTER TANK FARM FACILITY

U.S. NUCLEAR REGULATORY COMMISION ONSITE OBSERVATION REPORT 

1.0 BACKGROUND: 

The National Defense Authorization Act (NDAA) authorizes U.S. Department of Energy (DOE), 

in consultation with the U.S. Nuclear Regulatory Commission (NRC), to determine whether 

certain radioactive waste related to the reprocessing of spent nuclear fuel is not high-level 

waste, provided certain criteria are met. The NDAA also requires NRC to monitor DOE disposal 

actions to assess compliance with 10 CFR Part 61, Subpart C, performance objectives for lowlevel waste. 

On September 7, 2005, DOE submitted a draft waste determination for residual waste incidental 

to reprocessing stored in the Idaho Nuclear Technology and Engineering Center Tank Farm 

Facility (INTEC TFF) to demonstrate compliance with the NDAA criteria including demonstration 

of compliance with the performance objectives in 10 CFR Part 61, Subpart C. In its consultation 

role, the NRC staff reviewed the draft waste determination and concluded that the NDAA criteria 

could be met for residual waste stored in the INTEC TFF. NRC documented the results of its 

review in a Technical Evaluation Report (TER) issued in October 2006. DOE issued a final 

waste determination in November 2006 taking into consideration the assumptions, conclusions, 

and recommendations documented in NRC’s TER. 

To carry out its monitoring responsibilities under the NDAA, NRC developed a monitoring plan 

for the INTEC TFF facility in April 2007 (ML070650066). The NRC conducted two onsite 

observations in 2007 to observe tank grouting operations (7 of 11 large tanks and 4 smaller 

tanks) at the INTEC TFF. All open items identified in the first onsite observation conducted in 

April 2007 (ML071300222) were closed in the August 2007 onsite observation (ML072570173). 

In August 2008, NRC staff participated in a third onsite observation to observe pipe grouting 

operations, radiation protection controls, and the environmental sampling program 

(ML082050071). No findings resulted from the three onsite observations. No significant tank 

farm closure activities occurred in calendar year 2009; therefore, NRC staff elected to forego an 

onsite observation. No significant closure activities occurred at the INTEC TFF in calendar year 

2010; however given the length of time that had elapsed since the last onsite observation, the 

NRC staff decided to conduct an onsite observation visit in August 2010. During the visit, NRC 

staff obtained updates on closure activities and schedules, met with state officials, and collected 

routine information related to several monitoring factors listed in NRC’s monitoring plan for the 

INTEC TFF (ML070650066), such as radiation protection and environmental monitoring 

programs. 

 
2 

2.0 NRC ONSITE OBSERVATION ACTIVITIES: 

2.1 Radiation Protection: 

2.1.1 Observation Scope:

During this onsite observation visit, the NRC staff engaged in discussions with DOE and DOE 

contractor staff regarding the radiation protection program and listened to presentations 

describing the current year activities with radiation protection at the INTEC TFF. 

Prior to the onsite observation, NRC staff also met with officials from the State of Idaho’s 

Department of Environmental Quality (DEQ) to discuss INTEC TFF radiation protection program 

and the State’s oversight and observations. 

2.1.2 Observation Results: 

The performance objective in 10 CFR 61.43 for protection of individuals during operations 

requires that waste disposal activities be carried out such that the radiation protection standards 

set forth in 10 CFR Part 20 are met and doses are maintained as low as reasonably achievable 

(ALARA). 

During the onsite observation, DOE provided NRC staff with presentations that illustrated the 

radiation protection program at INTEC TFF. The presentations gave perspective on the 

activities at INTEC TFF during the tank closure and monitoring operations. DOE’s approach to 

demonstrating protection of individuals during operations is found in 10 CFR Part 835 and 

relevant DOE orders. DOE’s occupational limits are comparable to NRC’s 10 CFR Part 20 dose 

limits of 1 mSv/yr [100 mrem/yr] at the site boundary (or to members of the public granted 

access to the site) from all pathways and less than 0.1 mSv/yr [10 mrem/yr] dose limit for air 

emissions at the maximum point of impact at the Idaho National Laboratory (INL) boundary. 

DOE in 10 CFR Part 835, has occupational dose limits for adults, 50 mSv/yr [5000 mrem/yr] that 

are also comparable to Part 20. 

DOE provided a presentation on exposure rates and results on worker dose calculations 

associated with the 2009 and 2010 INTEC TFF work. The presentation focused on the Total 

Effective Dose and Equivalent Dose ALARA goals measured against the actual calculate 

values. The ALARA goals and actual data were very conservative and well below the 10 CFR 

Part 20 limits. 

Independent of the DOE presentation, the NRC staff also reviewed radiological surveys, 

bioassay program data and DOE’s Annual Site Environmental Reports. The reports provided 

the staff with information on methodology used to calculate doses to members of the public. 

DOE has continued to collect data and has provided analysis that demonstrates compliance 

with radiation protection for workers and members of the public. 

2.1.3 Conclusions: 

DOE staff was responsive in answering any NRC questions. After the presentations and 

discussion with DOE, the NRC staff participated in a site tour. Based on the information 
3 

presented by DOE, NRC’s review of documentation and site tour; NRC staff is confident that the 

current radiation protection program at INTEC TFF can meet the performance objectives as 

stated in 10 CFR 61.43. DOE provided proper documentation to demonstrate that activities 

were being conduct in a manner that is protective of individuals during operations. 

2.2 Groundwater Monitoring: 

2.2.1 Observation Scope: 

During this onsite observation visit, NRC staff listened to presentations and participated in 

discussions with DOE and contractor staff regarding ongoing remedial actions and groundwater 

monitoring activities performed under the Comprehensive Environmental Response, 

Compensation, and Liability Act (CERCLA) program at the INTEC TFF. 

Prior to the onsite observation, NRC staff also met with officials from the State of Idaho’s DEQ 

to discuss its oversight of the site, specifically its environmental monitoring program. 

2.2.2 Observation Results: 

State of Idaho DEQ provided presentations on its environmental monitoring program and 

information about groundwater monitoring data collected at INTEC and the larger INL site. NRC 

staff periodically review Idaho DEQ quarterly and annual monitoring reports and partially rely on 

this information and Idaho DEQ’s oversight of DOE operations and facility to support its 

monitoring responsibilities under the NDAA. 

DOE provided a presentation on CERCLA remedial actions and groundwater monitoring 

conducted at the INTEC. While CERCLA monitoring is focused on historical releases and does 

not exclusively support tank closure, it does provide useful information regarding the 

hydrogeological system at INTEC and a basis of comparison of INTEC TFF Performance 

Assessment (PA) modeling results to data. NRC staff has remained cognizant of ongoing 

CERCLA activities and has reviewed extensive groundwater modeling and data analysis reports 

over the past several years. NRC evaluation of data and information collected under the 

CERCLA program are discussed in more detail in its technical evaluation report related to 

INTEC TFF closure (NRC, 2006) and in periodic (annual) compliance monitoring reports (NRC, 

2008; NRC, 2009) that document the results of NRC’s consultation and monitoring 

responsibilities under the NDAA. Technical reviews of environmental data support NRC’s Key 

Monitoring Area (KMA) 3—Hydrological Uncertainties—related to DOE’s demonstration of 

compliance with 10 CFR 61.41, as well as KMA 4 related to DOE’s demonstration of compliance 

with 10 CFR 61.43, “Protection of Individuals During Operations” listed in NRC’s monitoring plan 

for the INTEC TFF (NRC, 2007) developed to help fulfill its responsibilities under the NDAA. 

DOE contractors discussed remedial actions conducted under the CERCLA program to reduce 

recharge sources and drain perched water located underneath the INTEC TFF to ensure that 

maximum contaminant level goals established under the CERCLA program can be met in the 

Snake River Plain Aquifer (SRPA) by the year 2095. Recharge controls include reduction or 

elimination of sources of recharge (e.g., landscape watering and piping leaks), and control of 

recharge through water collection and diversion (e.g., construction of low permeability asphalt 

surfaces and diversion of facility runoff to lined ditches that drain to a lined evaporation pond). 
4 

Monitoring of perched and saturated groundwater is conducted in part to determine the 

effectiveness of remedial actions to help ensure protection of human health. NRC staff was 

provided an opportunity to discuss groundwater monitoring issues identified during its review of 

DOE’s PA for the INTEC TFF (DOE Idaho, 2003) with DOE contractors working on CERCLArelated environmental monitoring programs. DOE contractor staff confirmed Performance 

Assessment Branch staff understanding of recent CERCLA monitoring results that indicate that 

only monitoring wells located very close to the Big Lost River (BLR) north the of the INTEC 

facility show a water level response following rare occasions when BLR flow occurs on site. 

DOE contractors indicated that BLR flow is currently thought to have little impact on perched 

water further away from the river near INTEC facilities, contrary to initial assumptions. Rather, 

anthropogenic sources of water are thought to have a much larger affect. DOE contractor staff 

also presented data on perched and SRPA groundwater sampling at INTEC. NRC staff review 

of this data indicates that known piping releases from INTEC are in close proximity to the facility 

with limited lateral movement primarily to the southeast of the facility (NRC, 2008; NRC, 2009) 

and in some cases potentially to the north of the facility (DOE Idaho, 2004). 

The data presented by DOE is consistent with NRC staff’s understanding of the recently revised 

hydrogeological conceptual model of the INTEC TFF based on its review of monitoring and 

modeling activities conducted under the CERCLA program. However, as documented in NRC 

staff’s TER and monitoring reports (NRC, 2006; NRC, 2008; and NRC, 2009), the monitoring 

results appear to be inconsistent with DOE PA modeling (DOE Idaho, 2003) predictions that 

show a very large impact of BLR flow on contaminant flow and transport of future TFF releases. 

As stated in a response to a follow-up Request for Additional Information (RAI) (DOE Idaho, 

2006a), the large lateral extent of the modeled contaminant plume diverted laterally 

approximately 600 meters to the south of the TFF (see Figure 1 below) is due completely to the 

pressure gradient that results from the steady-state infiltration boundary condition for the BLR. 

In this response, DOE goes on to state that the large lateral extent of the contaminant plume is 

not indicative of perched water. As documented in NRC staff’s TER (NRC, 2006), DOE’s 

response to NRC’s inquiry regarding the cause of the large lateral spread (DOE Idaho, 2006a) 

appears inconsistent with explanations provided in the actual PA documentation itself (DOE 

Idaho, 2003)—DOE’s PA indicates that the numerical model predicts contaminant transport 

around the perched zones and through breaks in the interbeds. In fact, the numerical model 

results show no perched zones along or near the flow path of the contaminant plume as 

described in the PA making the relevance of the statement regarding perched water unclear. 

Additionally, there is no indication from the monitoring data that when BLR flow does occur that 

contamination could be deflected nearly half a mile laterally to the south of the TFF. Due to the 

uncertainties in the PA modeling predictions and due to the large amount of credit that appears 

to have been given to vadose zone performance in DOE’s PA model with respect to dilution 

(approximately four orders of magnitude or a factor of 10,000 as shown in Figure 2 below [see 

difference in peak concentrations between zones 1 and 2 at the source and zone 4 at the 

vadose zone “spill-way” provided in DOE, 2006b]), NRC staff continues to recommend that DOE 

consider new and significant information collected under the CERCLA program in decisions to 

update its PA or in any future updates to its PA. Additionally, vadose zone transport 

mechanisms are important as they impact remediation and monitoring. For example, if this 

phenomena (i.e., large lateral deflection of INTEC TFF releases due to BLR imposed pressure 

gradients) actually occurs at INTEC or were to occur in the future, it could complicate 

remediation and monitoring of historical releases or monitoring of future releases that may occur 

from the INTEC TFF. 
5 

Figure 1-Technetium plume emanating from the INTEC TFF diverted laterally approximately 600 

m to the south. Locations near the source (zones 1 and 2), at the modeled “spill-way” (zone 4) 

and at the water table (zone 5) are also depicted. See Figure 2 below for technetium 

concentrations at these locations through time (DOE, 2006b). 

Figure 2-Technetium concentrations at zone locations 1 through 5 versus time (DOE, 2006b). 
6 

In fact, DOE indicated that it is in the process of determining whether its PA model needs to be 

updated. Given the risk significance of the groundwater model and additional CERCLA data 

that has come to light since development of the PA, NRC staff specifically recommended that 

DOE update its PA documentation (through an errata sheet or other textual revision) to clarify 

the cause of the lateral spreading of the contaminant plume and its risk significance as 

documented in responses to NRC RAIs (see DOE Idaho, 2006a and DOE Idaho, 2006b). NRC 

staff also recommended that DOE consider data and modeling conducted under the CERCLA 

program that has resulted in a revised hydrogeological conceptual model for the INTEC in 

determining whether to conduct additional modeling in an update to its PA. 

2.2.3 Conclusions and Follow-up Actions: 

NRC and DOE staff discussed monitoring conducted under the CERCLA program for the INTEC 

facility. NRC staff made two recommendations for DOE to consider in its decision to update the 

PA. NRC staff recommended that the PA reflect the results of simulations performed and 

additional documentation generated during the NDAA consultation process to answer NRC staff 

inquiry regarding the cause and performance impact of the significant lateral spread of the 

contaminant plume emanating from the TFF to the south (e.g., caused by pressure gradient 

from BLR seepage and resulted in up to a factor of 10,000 decrease in contaminant 

concentrations emanating from the tank farm facility for relatively mobile [non-sorbing] 

constituents such as Tc-99 and I-129). NRC staff also recommended that DOE consider (in its 

decision to update the PA) recent data collected under the CERCLA program that appears to be 

inconsistent with the DOE PA modeling results with respect to the impact of BLR flow on 

contaminant fate and transport at the INTEC TFF. NRC staff recommends that DOE should 

consider the new information in the next update to its PA maintenance plan. 

3.0 PARTICIPANTS: 

NRC Observation Team 

Barr, Cynthia 

Heath, Maurice 

Suber, Gregory 

Idaho Department of Environmental Quality 

LaRue, Bruce 

Partial List of DOE Representatives 

Shaw, Robert (Mark) 

Butterworth, Steve 

Forbes, Jeff 

Gray, Douglas 

Harris, Trent 

Long, Jeff 

 
7 

4.0 REFERENCES: 

DOE Idaho. DOE/ID–10966, “Performance Assessment for the Tank Farm Facility at the Idaho 

National Engineering and Environmental Laboratory.” Rev. 1. (Errata December 2, 2003). 

Idaho Falls, Idaho: DOE Idaho. 2003. 

DOE Idaho. “Evaluation of Tc-99 in Groundwater at INTEC: Summary of Phase 1 Results.” 

ICP/EXT–04-244. Rev. 0. Idaho Falls, Idaho: DOE Idaho. September 2004. 

DOE Idaho. “Follow-up Item from June 1 and 20, 2006, Meetings with DOE on INL TFF Waste 

Determination (Related to the large lateral extent of the contaminant plume).” Idaho Falls, 

Idaho: DOE Idaho. 2006a. 

DOE Idaho. “Follow-up Item from June 1 and 20, 2006, Meetings with DOE on INL TFF Waste 

Determination (Providing center-line plume concentrations).” Idaho Falls, Idaho: DOE Idaho. 

2006b. 

NRC. “NRC Periodic Compliance Monitoring Report for U.S. Department of Energy Non-HighLevel Waste Disposal Actions—Annual Report for Calendar Year 2007.” NUREG-1911. 

Washington DC: NRC, 2008. ML082280145 

NRC. “NRC Periodic Compliance Monitoring Report for U.S. Department of Energy Non-HighLevel Waste Disposal Actions—Annual Report for Calendar Year 200 

8.” NUREG-1911, Revision 1. Washington DC: NRC, 2009. ML091400501 

NRC. "U.S. Nuclear Regulatory Commission Plan for Monitoring Disposal Actions Taken by the 

U.S. Department of Energy at the Idaho National Laboratory Idaho Nuclear Technology and 

Engineering Center Tank Farm Facility in Accordance with the National Defense Authorization 

Act for Fiscal Year 2005." Washington, D.C.: NRC. 2007. ML070650222 

NRC. "U.S. Nuclear Regulatory Commission Technical Evaluation Report for the U.S. 

Department of Energy Idaho National Laboratory Site Draft Section 3116 Waste Determination 

for Idaho Nuclear Technology and Engineering Center Tank Farm Facility." Washington, DC: 

NRC, 2006. ML052630012