To expand the storage capacity of highly enriched uranium stockpiles, the Company has won a contract to store canisters containing U-235 in the General Materials Storage Warehouse. Your task is to move canisters into the three storage rooms to obtain maximum loading, while maintaining criticality safety within regulations. You may have as many canisters of all types as you may request, but all must be stored within the three rooms available.

 

Regulations require a Criticality Safety Evaluation (CSE) to ensure an accidental criticality does not occur.

 

Canister and Location Destinations

 

	Canister	Storage Location
A	One gallon plastic buckets	Room 1
B	Five Gallon plastic buckets	Room 2
C	32 gallon plastic tubs	Room 3
	Flat stackable lids are attached to each container

 

 

 

GUIDELINES

The CSE must be written to the required format below. 

 

1.0 Introduction

Explain why the work is being done

Describe basic process that will occur

Purpose of the CSE

Administrative references, standards, procedures, etc.

 

2.0 Description

Overview of the procedural steps

Important interactions with preceding and following processes (and any others)

Hardware

Gloveboxes, canisters, storage racks, etc. (Include pictures or diagrams)

Relative positions, etc.

Special materials

Variations allowed in geometry and process (important to criticality)

 

3.0 Methodology

Indicate reliance on ANS-8.1 limits and/or hand calculational techniques

 

4.0 Contingencies

 

4.1 Mass

4.2 Absorber

4.3 Geometry

4.4 Interaction

4.5 Concentration

4.6 Moderation

4.7 Enrichment

4.8 Reflection

4.9 Volume

 

Contingency Table

(MAGICMERV)

 

Critical Parameter	Normal	Contingency	Controls
Mass
Absorber
Geometry
Interaction
Concentration
Moderation
Enrichment
Reflection
Volume

 

5.0 Normal & accident analysis

 

6.0 Postings & controls

Engineered safety features

Administrative controls

Operator aids

Procedural changes

Postings

 

7.0 Summary & conclusions

 

8.0 Appendices

 

 

 

ASSUMPTIONS

Parameters:

 

1. You may have as many canisters as you need.

 

1. You may put any controls you deem necessary on the HANDLING and STORAGE of the canisters while in the building.

 

1. We want to store as many grams of 100% enriched U-235 as possible.

 

1. The canisters will be loaded somewhere else and brought to the building using procedures that you are not responsible for. Each will be labeled with the mass of U-235 in the canister and its enrichment; each of these two values is known within a 10% error.

 

1. Assume an appropriate uncertainty on any dimension measurement you make. You decide based on the measurements you make, but be sure that this determination is documented in your NCSE (Nuclear Criticality Safety Evaluation).

 

1. The uranium will be assumed to be uniformly mixed with water. (You have no control over this, so must assume the worst moderation and shape. The container will NOT necessarily be filled with a uranium/water mixture—it may be a more concentrated sphere surrounded by water to fill the container.)

 

1. The building is a two story, general purpose storage building. All walls and floors in the building (even interior walls) will be assumed to be concrete. Each student will be allocated a separate storage room for his canisters. You can design the location of the storage racks. All rooms are adjacent to each other as shown:

 

1. Site fire protection tells us that the fire sprinklers are capable of filling the air with 0.01 g/cc water mist in ALL rooms in the building AND that water could accumulate as deep as 4 inches on the floor.