ABSTRACT It has been revealed from the experiences of Decontamination and Decommissioning (D&amp;D) activities that even a small improvement in performance can result in significant risk reduction and cost savings. For example, Race Scan Ear Mic System, which was originally developed for communications between racecar drivers and crews in loud environments, has been successfully applied to D&amp;D work and proved to enhance worker safety and communications. Glovebox dismantlement is an important and costly process in D&amp;D activities of nuclear facilities. Adequate decontamination and size reduction of the gloveboxes are especially important in this activity because they have the potential to reduce risks and costs significantly. This paper presents some simple approaches to support D&amp;D tasks and discusses their potential advantages. Examples discussed include: • Repeated shear wiping of large pipes and ducts • Application of thin layers on radiological counters for uninterrupted use • Partial use of robotics for glovebox dismantling The paper also discusses schematics for protecting equipment interiors and/or glovebox inner surfaces from contamination, which may result in significant savings and waste minimization upon future dismantlement. Examples discussed include: • Smart coating for contamination prevention • Protecting equipment by geometrically simple cove

Akihiro Kitamura

Dianne W Wilburn

Ellen Stallings

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WM’03 Conference, February 23-27, Tucson, AZ 
1 
GLOVEBOX DISMANTLEMENT AND EQUIPMENT PROTECTION  
IN CONTAMINATED ENVIRONMENTS  
 
Akihiro Kitamura†  
Waste Management Division, Pu Fuel Center, Japan Nuclear Cycle Development Institute (JNC)  
4-33 Muramatsu, Tokai-mura, Naka-gun, Ibaraki 319-1194, Japan 
 
Ellen Stallings and Dianne W. Wilburn 
Risk Reduction & Environmental Stewardship (RRES) Division, Los Alamos National Laboratory  
Los Alamos, NM 87545 
 
ABSTRACT 
 
It has been revealed from the experiences of Decontamination and Decommissioning (D&D) 
activities that even a small improvement in performance can result in significant risk reduction and 
cost savings. For example, Race Scan Ear Mic System, which was originally developed for 
communications between racecar drivers and crews in loud environments, has been successfully 
applied to D&D work and proved to enhance worker safety and communications. Glovebox 
dismantlement is an important and costly process in D&D activities of nuclear facilities. Adequate 
decontamination and size reduction of the gloveboxes are especially important in this activity 
because they have the potential to reduce risks and costs significantly. This paper presents some 
simple approaches to support D&D tasks and discusses their potential advantages. Examples 
discussed include:  
 
• Repeated shear wiping of large pipes and ducts  
• Application of thin layers on radiological counters for uninterrupted use 
• Partial use of robotics for glovebox dismantling  
 
The paper also discusses schematics for protecting equipment interiors and/or glovebox inner 
surfaces from contamination, which may result in significant savings and waste minimization upon 
future dismantlement. Examples discussed include: 
 
• Smart coating for contamination prevention  
• Protecting equipment by geometrically simple cover 
 
INTRODUCTION  
 
The quality of Decontamination and Decommissioning of nuclear facilities depends heavily on 
budgets, resources, schedules, etc., and is influenced by external factors, such as regulations, 
strategies, and resource availability. Circumstances can be transitory and change with time. 
Therefore, it is important to develop a plan of action for D&D activities through optimization 
rather than evolution. Adopting methodologies and technologies in terms of practicality and 
applicability of existing practices, as well as taking advantage of opportunities to enhance 
efficiency and safety through adoption of new or alternative techniques, are both important to 
increase efficiencies.   
 
Experience in the US and elsewhere has shown that it is a valuable exercise for an organization 
with substantial nuclear facilities to regularly review the potential for improving the efficiency of 
decommissioning planning activities at all levels. Even a very small improvement in planning 
_____________ 
† On sabbatical leave at Risk Reduction & Environmental Stewardship (RRES) Division, Los Alamos  
  National Laboratory  
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efficiency can result in significant cost savings over the long term (1).  
 
Here we consider small performance changes, such as application of existing methods to new 
aspects, extension of existing methods, design or creation of simple tools to enhance worker safety, 
etc., in dismantling of gloveboxes to enable work crews to save time, effort, and to enhance 
personal safety in D&D operations.   
 
DECONTAMINATION   
 
Enhancement in the efficiency and effectiveness of the decontamination of gloveboxes and 
equipment interiors is important because, if adequately applied, it will results in significant cost 
savings (For example, Rocky Flats decontaminated a number of gloveboxes by cerium spray 
decontamination, which allowed the boxes to be disposed as low level waste as opposed to disposal 
as TRU waste (2). This resulted in significant disposal costs savings). However, there are still a 
number of issues to be resolved regarding decontamination due to complicated geometries, crevice 
areas, congested areas, difficulties with fixed contamination, generation of secondary wastes, 
appropriate characterization of material before and after decontamination, etc. Here, we present 
option to circumvent the described difficulties. 
 
Repeated shear wiping of large pipes and ducts 
 
It is difficult to decontaminate inner surfaces of large pipes and ducts that are contaminated. Even if 
the decontamination agents are adequately applied, it is still difficult to remove them with the 
contaminants.  
 
The following scheme indicates the process toward this difficult task. 
 
     
     1           2            3            4            5            6            7 
 
 
      
 
      
 
               
     
Pump    Bag for decontamination    Cut and seal the bag        Entrapping first bag 
Contaminated pipe or duct  Blowing air into first bag   Blowing air into second bag   Fix contamination          
 
Figure1. The schematic procedure of repeated shear wiping method. 
 
1. Two sheets (bags) are placed at the both ends of pipe or duct with air pumps. Decontamination 
agents are either applied to the inner surface of the pipe or coated on the surface of the sheet. 
2. Air is induced into one of the sheets. As the sheet moves, the resulting shear stress at the 
contact surface decontaminates and wipes out the contaminants. 
WM’03 Conference, February 23-27, Tucson, AZ 
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3. The contaminated surface of the sheet is captured by the other sheet.  
4. When the operation ends, the end of previous sheet is cut and depressurized. The other part of 
the same sheet is sealed for future usage.  
5. Second sheet is blown by air as step 2, and resulting shear will again wipe and decontaminate 
the inner surface.  
6. The contaminated surface of the sheet is captured again by the next sheet. At this point, the 
very first contaminated sheet is sandwiched between these two sheets. 
7. Repeat the above process until contamination level of the surface is at the desired level. Finally, 
cut both ends of sheets and finish the procedure. 
 
The important points of this method are:  
 
• Operations could handled remotely  
• Contaminated surfaces are always covered  
• After the process, the inner surface of pipe is covered so that existing contamination is 
appropriately fixed 
 
Use of spin coating to produce uniform thin layers for detector head protection 
 
In the course of decontamination, it is key to survey for the level of surface contamination both 
before and after decontamination work takes place. In doing so, it is preferable to limit or exclude 
contamination of the detector while not impairing detection capability. Application of thin layers on 
the detector head has potential for meeting these requirements. If the layers could be easily peeled 
by hand, then the measurement could continue without interruption, even if the top layer were 
contaminated. 
 
The method of spin coating is widely used to produce thin layers on materials with relatively ease. 
Spin coating is a technique to produce very thin and uniform films (with the final thickness ranging 
in between 10~100µm) by the centrifugal spinning of viscous liquids on a rotating disk (3). 
Because of its simple manipulation, it could easily be used to fulfill the above requirement as 
follows:  
 
• First apply the strippable coating in liquid form to the surface of the detector head, and rotate to 
make a thin and uniform layer 
• Make pull tabs so that the layer can remove easily 
• Next, apply a second droplet and spin to form another layer 
• Repeat above procedure as many times until the total thickness of layers affects detection  
 
In this manner we could survey the surface of the contaminated material repeatedly by peeling off 
the upper layer whenever it became contaminated. Determining factors would be:  
 
• Material to be used as strippable coating 
• Adequate final thickness of the layer 
• The number of the layers 
 
SIZE REDUCTION  
 
In the course of dismantling, size reduction operations comprise a large amount of the total work 
effort. Therefore, it is important to have systematic ways to operate size reduction activities. The 
ability to perform these cutting activities remotely is desired. We will discuss options to conduct 
size reduction operations to maximize efficiency.  
 
WM’03 Conference, February 23-27, Tucson, AZ 
4 
Partial use of robotic for size reduction 
 
Since some of the size reduction works face thick material cuttings, simple but time consuming 
activities, or constantly repeated works, the use of robotics plays important role in reducing worker 
exposure and hazard. Although these systematical approaches are recommended, it is still difficult 
to install robotics in full scale into the dismantlement field (For example, there are unknowns such 
as the amount of time to fix or repair equipment). There is also the uncertainty that the robotics will 
not operate as designed for their intended use. However, if we could combine the manual procedure 
with the robotics adequately, a rational scheme can be implemented. Japan Nuclear Cycle 
Development Institute (JNC) has been conducting glovebox strip-out operations in the glovebox 
dismantling facility successfully by using 80% manual and 20% robotics (4). Activities include: 
 
• Unfastening bolts and removing panels from the gloveboxes   
• Cutting the glovebox body and ceiling by plasma arc  
 
Although this operation is currently conducted against standard sized gloveboxes (dimension of 3m 
× 3m × 1m), the success in the partial use of robotics highly recommends the use of similar 
methodologies in other facilities with various types gloveboxes.  
 
Vacant rooms for decontamination and dismantlement 
 
The Decontamination and Volume Reduction System (DVRS) was designed and deployed by a 
team, comprised of members from national laboratories and the private sector, at Los Alamos 
National Laboratory (LANL) to demonstrate decontamination and size reduction of the 
contaminated gloveboxes (5). DVRS is an integrated system for decontaminating TRU metallic 
waste to low level waste, and significantly reduces the total volume of waste for disposal. 
 
DVRS has two rooms for decontamination and size reduction. The concept of these vacant rooms 
may serve to optimize the operation. In the past, there has been a tendency to install full-sized 
equipment in tight conditions in the glovebox for decontamination or dismantling equipment. It 
was, therefore, very difficult to maintain or replace the equipment. Also there is a danger that if the 
equipment, once install, was found to be useless, it would require a large expenditure of time and 
money to exchange the equipment. The vacant rooms concept enables us to treat such difficulty 
easier by simply replacing equipment by hand. The improved rooms might be obtained by 
considering the following design options: 
 
• Curved construction at the floor and wall corner 
• Two layer (plastic + painting) protection of the room  
• Drainage system 
• Valid containment design for doors 
 
CONTAMINATION PREVENTION 
 
Decontamination and size reduction works are difficult and time-consuming activities. If we could 
prevent contamination for equipment those of which we anticipate to be dismantled in the future, it 
would greatly increase the efficiencies for the dismantling work. Here we present some options to 
prevent contamination by coating equipment and surfaces before installation into the contaminated 
environment. 
 
Smart coating for contamination prevention and waste minimization 
 
Smart coating is a nontoxic water-based polymeric coating which provides vivid color change in 
WM’03 Conference, February 23-27, Tucson, AZ 
5 
the regions of contamination (6). The material is composed of polyvinyl alcohol (PVA), poly vinyl 
pyrrolidone (PVP) and 2-(5-bromo-2-pyridylazo)-5-diethylaminophenol (BrPADAP). Addition of 
PVP and BrPADAP are, respectively, for improvement of adherence and colorimetric indicator. 
PVP acts as a solubilizer for the BrPADAP in PVA as well. Smart coating exhibits different color 
changes for different contaminant (orange to purple for uranium and orange to red for plutonium) 
and is effective at removing varying levels of both contaminants from different types of surfaces. 
Since the areas of contamination are indicated by a color change, it is intended to be use as and 
efficient and effective decontamination and segregation methods, because contaminated portions of 
the coating can be separated from uncontaminated areas and treated accordingly. 
 
Although still expensive for commercial use, this method may also be used to prevent 
contamination. If applied to D&D work areas, newly generated contamination areas or spots can be 
determined quite certainly and easily, which could avoid extensive decontamination work since 
contamination in large suspected area can not usually be determined and in most situations it is 
necessary to decontaminate the whole suspected area. It will therefore eliminate the possibilities of 
unnecessary decontamination work and schedule delay. 
 
Protecting equipment by geometrically simple cover 
 
Equipment dismantling is one of the most difficult activities in D&D operation, because its 
complexity in geometry resists many types of decontamination and its thickness makes size 
reduction work difficult. If we could appropriately coat the equipment before installation in the 
gloveboxes, we may treat equipment dismantling much easier and costless at the time of 
decommissioning. Here is one scheme that resolves this difficulty:  
 
• Cover the equipment by thin plastic type material that has a simple form (such as cylindrical 
geometry) except for the parts necessary for direct contact and/or maintenance 
• Strip coat on this plastic cover 
• At the time of dismantling use Fogging (air stream containing a glycerin/saccharide fog) (7) to 
reduce airborne contamination and then apply strip coat again (Fog & Strip) to sandwich the 
contamination 
• Strip plastic cover along with strip coat in another (relatively clean) controlled area 
 
In this way we can have, not to say clean waste but, very low level radioactive waste for 
TRU assumed waste, and significant cost and workforce reductions are expected. 
 
APPLICATION OF LANL TECHNOLOGIES 
 
LANL’s Large Scale Demonstration and Deployment Project (LSDDP) is identifying and 
demonstrating technologies to reduce the cost and risk for management of transuranic element 
contaminated objects (including gloveboxes). Some of these technologies have already been 
demonstrated to be useful. However, they have the potential to be used in another area as well.   
 
Application of NTvision in another circumstances 
 
NTvision was developed as a security camera system with features that are particularly interesting 
to DVRS operations (8). The system may be applied as a support of safeguards activities, those of 
which some of countries (including Japan) are obligated to ensure no unreported work has been 
done (for example, the system can be made as remote monitoring system in unattended mode). 
Also, it may be used for making decisions such as which one (of the waste boxes) should be treated 
first, as well as to enhance the review process of the waste management work, and improve quality 
assurance that waste has been properly characterized and disposed. 
WM’03 Conference, February 23-27, Tucson, AZ 
6 
 
AeroGo air pallet system 
 
The AeroGo air pallet system includes air casters, air hose, and pressure manifold distribution 
control box to “float” loads on a virtually frictionless film of air. The reduced friction and 
omni-directional movement allow the operator to precisely place and align the load in a limited 
workspace (8). The AeroGo air pallet demonstration proved air pallets are a superior method of 
placement of the waste crates in the Large Item Neutron Counter (LINC) for initial radionuclide 
surveys. This technology facilitated easy movement placement of very large crates in precise 
locations in the LINC. This system may be applied to settle the gloveboxes in the size reduction 
area for robotic manipulation. Also it is it may be applicable for adequately setting and placing the 
container for the waste treatment. The use of the system in every possible situation will eventually 
enhance overall worker safety. 
 
CONCLUSION 
 
We have shown some simple but effective methods to assist glovebox decontamination and 
dismantling work. Enhancements like these kinds of small improvements are definitely important 
for increasing efficiencies and reducing costs and risks. Even if they fail, we have the opportunity 
to collect lessons learned, determine what went wrong, and improve future D&D work. 
 
ACKNOWLEDGEMENT 
 
A. K. acknowledges the hospitality of the Science Technology/Science Application Group, Risk 
Reduction and Environmental Stewardship (RRES) Division of Los Alamos National Laboratory, 
where this work was conducted. 
 
REFERENCES 
 
1. A. Bishop and P. A. V. Johnson, “Comparison of UK and USA Decommissioning Planning 
Methodologies – Part B: USA Methodology,” AEAT-3920 (1998).  
2. N. R. Tuor and A. L. Schubert, “Closing Rocky Flats by 2006,” Proceedings of WM’02, 
Tucson AZ, February 24-28, 2002. 
3. R.G. Larson and T. G. Rehg, Spin Coating, In Liquid Flim Coating (eds. S. K. Kistler and P. M. 
Schweizer), pp. 709-734, Chapman Hall (1997). 
4. S. Uematsu, K. Kashiro, N. Tobita, “Dismantling of gloveboxes for MOX fuel fabrication by a 
glovebox dismantling facility,” Proceedings of WM’02, Tucson AZ, February 24-28, 2002. 
5. DVRS Home Page: http://dvrs.lanl.gov/ 
6. H. N. Gray, B. Jorgensen, D. L. McClaugherty, and A. Kippenberger, “Smart polymeric 
coatings for surface decontamination,” Ind. Eng. Chem. Res. 40, 3540-3546 (2001). 
7. J. McFee, E. Stalling, M. Romero, K. Barbour, “Improved technologies for decontamination of 
crated large metal,” Proceedings of WM’02, Tucson AZ, February 24-28, 2002. 
8. Los Alamos National Laboratory Environmental Science and Technology Home Page: 
http://www-emtd.lanl.gov/TD/Technology.html 


GLOVEBOX DISMANTLEMENT AND EQUIPMENT PROTECTION IN CONTAMINATED ENVIRONMENTS

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GLOVEBOX DISMANTLEMENT AND EQUIPMENT PROTECTION IN CONTAMINATED ENVIRONMENTS

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