International Isotopes Fluorine Products, Inc. (IIFP) 

A Wholly Owned Subsidiary of 

International Isotopes, Inc. (INIS) 

Fluorine Extraction Process & Depleted 

Uranium De-conversion 

 (FEP/DUP) Plant 

License Application 

Chapter 6 

Chemical Process Safety 

Revision B 

December 8, 2011

 

LA-IFP-001 Revision B CHAPTER 6 
LA-IFP-001 Revision B CHAPTER 6 December 8, 2011 

 Page 6-ii

TABLE OF CONTENTS 

LIST OF FIGURES ................................................................................................................................. 6-iii 

LIST OF TABLES................................................................................................................................... 6-iii 

ACRONYMS and ABBREVIATIONS (Provided In License Application Chapter 1 Revision B) 

6 CHEMICAL PROCESS SAFETY .................................................................................................. 6-1

6.1 PROCESS CHEMICAL HAZARDS ..................................................................................... 6-1 

6.2 PROCESS CHEMICAL RISK AND ACCIDENT SEQUENCES ........................................ 6-4

6.2.1 Process Descriptions.................................................................................................. 6-4

6.2.2 Consequences and Likelihoods of Accident Sequences ............................................ 6-5

6.2.3 Chemical Release Scenario Techniques and Assumptions ....................................... 6-6

6.2.3.1         Worker Exposure .................................................................................... 6-6

6.2.3.2 Public Exposure ..................................................................................... 6-7

6.2.4 Source Term and Dispersion Models ........................................................................ 6-7 

6.2.5 Description of Chemical Dispersion Models ............................................................ 6-7

6.2.6 Chemical Exposure Standards ................................................................................... 6-7 

6.3 ITEMS RELIED ON FOR SAFETY AND MANAGEMENT MEASURES........................ 6-8

6.3.1 Chemical Safety Approach ........................................................................................ 6-8

6.3.1.1 Chemical Process Safety Program ......................................................... 6-8

6.3.1.2 Materials of Construction, Sizing of Equipment, System .......................... 

 Fabrication and Process Control Schemes ........................................... 6-11

6.3.2 Chemical Process Safety Controls .......................................................................... 6-13

6.3.3 Chemical Process Safety Management Measures ................................................... 6-14

6.3.3.1 Procedures to Ensure Reliable Operation of Engineered Controls ...... 6-14

6.3.3.2 Procedures to Ensure Proper Implementation of Administrative ............... 

 Controls................................................................................................ 6-14 

6.4 REQUIREMENTS FOR NEW FACILITIES ...................................................................... 6-14

REFERENCES .................................................................................................................................. 6-16

LIST OF FIGURES 
LA-IFP-001 Revision B CHAPTER 6 December 8, 2011 

 Page 6-iii

No List of Figures Entries 

LIST OF TABLES 

Table 6-1 Chemical Consequence Severity Levels (Defined by 10 CFR 70.61) ............................... 6-5

Table 6-2 Chemical Consequence Values ......................................................................................... 6-7
LA-IFP-001 Revision B CHAPTER 6 December 8, 2011 

Page 6-1

6 CHEMICAL PROCESS SAFETY 

International Isotopes Fluorine Products, Inc. (IIFP), a wholly owned subsidiary of International Isotopes, 

Inc. (INIS), will build and operate a depleted uranium processing facility near Hobbs in Lea County, New 

Mexico. The IIFP Facility that is also referred to as the FEP/DUP Plant is being licensed under Title 10 

Code of Federal Regulations (CFR) Part 40. A summary description of the planned facility is provided in 

the IIFP License Application (LA), Revision B Chapter 1 “General Information.” 

This Chapter 6 of the IIFP LA describes the chemical classification process, the hazards of process 

chemicals of concern, process interactions with chemicals affecting licensed materials and/or hazardous 

chemicals produced from licensed material. It also describes the methodology for evaluating hazardous 

chemical consequences and the chemical safety assurance features. 

The IIFP Chemical Process Safety (CPS) Program has been developed consistent with the guidance in 

Chapter 6 of NUREG-1520, “Standard Review Plan for the Review of a License Application for a Fuel 

Cycle Facility,” U.S. Nuclear Regulatory Commission (NRC, 2002), NUREG-1513, “Integrated Safety 

Analysis Guidance Document,” (NRC, 2001), NUREG-1601, “Chemical Process Safety at Fuel Cycle 

Facilities,” (NRC, 1997a), NUREG/CR-6410, “Nuclear Fuel Cycle Facility Accident Analysis 

Handbook,” (NRC, 1998) and NUREG/CR-6481, “Review of Models Used for Determining 

Consequences of UF6 Release,” (NRC, 1997b). The CPS Program also complies with 10 CFR 70.61, 

“Performance Requirements,” (CFR, 2009a), 10 CFR 70.62, “Safety Program and Integrated Safety 

Analysis,” (CFR, 2009b), 10 CFR 70.64, “Requirements for New Facilities or New Processes at Existing 

Facilities,” (CFR, 2009c) and other applicable 10 CFR 70, Subpart H requirements. 

6.1 PROCESS CHEMICAL HAZARDS 

Throughout Chapter 6, in the discussion of the chemical aspects of uranium hexafluoride (UF6), uranium 

tetrafluoride (UF4) and uranium oxide (UO2 or U3O8), the conventional chemical formula is used 

frequently rather than always referring to those as the “depleted” assay uranium compounds. The 

associated hazards are the same except that depleted uranium materials would exhibit lower radioactivity 

levels than would natural or enriched uranium materials. 

The chemical process hazards associated with the IIFP Facility involve the processing, handling, 

packaging and storage of chemical materials, including: 

• Depleted uranium hexafluoride (DUF6) 

• Depleted uranium oxides (likely a mix of DUO2 and the higher oxide states including DU3O8) 

• Depleted uranium tetrafluoride (DUF4) 

• Anhydrous hydrofluoric acid (AHF) and hydrofluoric acid (HF) 

• Hydrogen (H2) 

• Potassium hydroxide (KOH) 

• Diboron trioxide (B2O3) and Silicon dioxide (SiO2) 

• Calcium fluoride (CaF2) 

• Boron trifluoride (BF3) and silicon tetrafluoride (SiF4) 

• Other hazardous chemicals such as depleted uranyl fluoride (DUO2F2) that could be produced 

during accident sequences. 
LA-IFP-001 Revision B CHAPTER 6 December 8, 2011 

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The detailed chemical reaction processes are described in the IIFP LA, Revision B Integrated Safety 

Analysis (ISA) Summary Section 3. The process buildings are discussed in the LA, Revision B Chapter 1 

Section 1.1.2. 

At the IIFP Facility, the Fluorine Extraction Process (FEP) Product Storage and Packaging Building, the 

AHF Staging Containment Building and the Fluoride Products Trailer Loading Building and equipment 

within these buildings are separated physically from areas involving licensed materials. These buildings 

are also equipped with ventilation systems that are separate from the licensed material process building 

systems. The AHF, SiF4 and BF3 chemicals stored and handled in these buildings have been chemically 

separated from licensed materials through several process separation stages. The BF3 and SiF4 products, 

although produced from fluorine extracted from DUF4, have been purified before being transferred to 

these storage and packaging areas. A Process Hazards Analysis (PHA) is conducted for chemicals and 

equipment in these areas to ensure safe design relative to industrial chemical safety, but the safety 

analysis and design for controls in these areas are outside the ISA envelope. 

A summary of the major process hazardous chemicals is provided below. Detailed hazard data will be 

contained in the facility Material Safety Data Sheet (MSDS) information and documents and be available 

to employees and contractors prior to bringing hazardous chemicals onto the IIFP Site. 

DUF6 is source material received at the IIFP Facility and used to produce DUF4. It is received at the IIFP 

Facility in approved shipping cylinders that contain the material in solid state. The cylinders are heated 

inside containment-type autoclaves to vaporize the DUF6 that is fed to the reaction vessel used for DUF4

production. The uranium component of the compound is radioactive and decays into a series of other 

radioactive elements emitting low levels of radiation. If DUF6 is released to the atmosphere, the 

compounds DUO2F2 and HF are produced by reaction with moisture in the air. The chemical hazard of 

UF6 greatly exceeds the radiation hazard. Uranium hexafluoride has a Threshold Limit Value (TLV) of 

0.2 mg/m3 as uranium and 2.5 mg/m3

 as fluoride and a Permissible Exposure Limit (PEL) of 0.05 mg/m3

as uranium (soluble), 0.25mg/m3

 as uranium (insoluble) and 2.5 mg/m3 as fluoride (NIH, 2011). 

DUO2F2 (uranium oxyfluoride; often referred to as uranyl fluoride) is not a normally used chemical at 

IIFP but may be formed in the event of a DUF6 accidental leak or release by the reaction of the UF6 with 

moisture in the atmosphere. It usually forms as a dense white finely sized particle and resembles white 

smoke. It may collect around any leak area as a white-to-pale yellow powder. It is very soluble in water. 

The TLV is the same as UF6 for uranium and fluoride. The PEL is 0.05 mg/m3 as soluble uranium (NIH, 

2011). 

Uranium oxides are a by-product solid generated at the IIFP Facility from the reaction of SiO2 with DUF4

or B2O3 with DUF4. The depleted uranium oxides can be a mixture of the lower oxide uranium (UO2) up 

to the higher oxide state (U3O8) depending on the formation reaction conditions. For the substance UO2, 

very fine particles (0.2-0.3 micrometers) may spontaneously react and ignite in air at elevated 

temperatures (300-700o

C) to form the higher state U3O8. The rate of this reaction is a function of particle 

size. The temperature requirement for spontaneous reaction will change accordingly (ORNL, 2000). 

Uranium oxides can be irritating to the eyes and be absorbed into the body if inhaled or ingested. The 

lungs may be affected by repeated or prolonged exposure to the dust particles. The uranium oxides have 

similar TLV and PEL values of the uranium component of uranium hexafluoride (NIH, 2011). 

DUF4 is the intermediate product generated at the IIFP Facility from the reaction of DUF6 + H2. It is a 

green, nonvolatile odorless crystalline solid that is nearly insoluble in water. It is used in the IIFP Fluorine 

Extraction Process as a major raw material to generate SiF4 and BF3. It can be harmful by inhalation, 
LA-IFP-001 Revision B CHAPTER 6 December 8, 2011 

Page 6-3

ingestion and through prolonged skin contact. DUF4 has similar TLV and PEL values as uranium 

hexafluoride (NIH, 2011). 

AHF is a by-product generated at the IIFP Facility from the reaction of DUF6 + H2. Hydrofluoric acid 

can also be present in a form that is not anhydrous and containing different percentage amounts of water. 

The reaction of DUF6, SiF4 or BF3 with moisture in the atmosphere or with water produces HF. HF is 

very toxic by inhalation. If HF comes in contact with the skin or if it is swallowed it causes severe burns. 

Inhalation of vapors in high concentration may cause shortness of breath (lung edema). HF is fibrogenic 

to the lungs in the context of an acute inhalation exposure complicated by potential of bronchiolitis 

obliterans. Ingestion causes burns of the upper digestive and respiratory tracts. When there is dermal 

exposure, HF penetrates the skin and without treatment can attack underlying tissues and bone. There is a 

risk of serious damage to eyes. Hydrogen fluoride is nonflammable. The gas has a pungent acid-like odor. 

MSDS information and medical treatment procedures for skin exposure are available and well known 

within the HF chemical industry. AHF has a TLV of 0.5 ppm as fluoride and a PEL of 3 ppm as fluoride 

(NIH, 2011). 

H2 gas is a feedstock chemical generated in a packaged unit on an as-demand basis at the IIFP Facility. It 

is reacted with DUF6 in the de-conversion process to produce HF and DUF4. Hydrogen poses a hazard to 

human safety from potential detonations and fires when mixed with air. Inhalation of air containing a high 

concentration of hydrogen can cause asphyxiation. Hydrogen is explosive and highly flammable (NIH, 

2011). 

BF3 is a product generated at the IIFP Facility from the reaction of B2O3 + DUF4. Boron trifluoride is a 

colorless gas with a pungent suffocating odor. It forms dense white fumes in moist air and is corrosive 

and can cause irritation of eye, nose, throat and skin. Acute toxicity may lead to hypoxemia or lung 

edema. It decomposes on contact with water forming toxic and corrosive hydrogen fluoride, fluoroboric 

acid and boric acid. The U.S. Occupational Safety and Health Administration (OSHA) PEL ceiling value 

is 1 ppm (NIH, 2011). 

SiF4 is a product generated at the IIFP Facility from the reaction of SiO2 + DUF4. The substance is a 

colorless gas with a pungent suffocating odor and fumes strongly in air. SiF4 is noncombustible but 

decomposes on heating producing toxic and corrosive fumes including hydrogen fluoride. It reacts with 

water to form hydrogen fluoride and fluorosilicic acid. It attacks many metals in the presence of water 

releasing hydrogen. The substance is corrosive to the eyes, the skin and the respiratory tract. Inhalation of 

this gas may cause lung edema. The TLV and the PEL are both published at 2.5 mg/m3

 as fluoride (NIH, 

2011). 

B2O3 is a feedstock chemical received at the IIFP Facility and used to generate BF3. The substance is 

colorless, semitransparent lumps or hard white odorless crystals. It is an eye, skin and respiratory irritant. 

The substance is very hazardous in case of ingestion. The boron component is considered to have 

hepatotoxin secondary effects. The TLV is 10 mg/m3

 and the PEL is 15 mg/m3, total dust (NIH, 2011). 

SiO2 (either as amorphous or crystalline) is a feedstock chemical received at the IIFP Facility used to 

generate SiF4. Amorphous SiO2 is a transparent to gray color odorless powder. Inhaling finely divided 

crystalline silica dust in very small quantities over time can lead to silicosis, bronchitis or cancer. 

Amorphous silica has slightly different properties from those of crystalline silica and is generally 

considered to be less hazardous. The substance is non-flammable, inert and harmless (except for 

inhalation over time). The TLV for the more hazardous crystalline form is 0.02 mg/m3

; respiratory 

fraction (NIH, 2011). 
LA-IFP-001 Revision B CHAPTER 6 December 8, 2011 

Page 6-4

Potassium hydroxide solution is used as a scrubbing media in the Plant KOH Scrubbing System with 

concentrations ranging from 2-20%. It is received in tank trucks as a solution at concentrations near 45% 

and loaded into the KOH inventory holding tank. It is diluted for recharging the scrubbing system when 

necessary. Most of the KOH in the inventory is from the regeneration of spent scrubber solution to a 15-

25% concentration range for recycling back to the facility scrubbing system. Occasionally, a fresh charge 

of 45% KOH is made to the scrubbing system as needed and that material is transferred from the KOH 

inventory holding tank. KOH (45% solution) is a clear, colorless liquid with a boiling point of slightly 

above 212o

F. It is stable under normal temperatures and pressures. It reacts with acids, organic materials, 

nitro compounds, acrolein, halogens, anhydrides, phosphorous and metals that react with water. 

Decomposition products are generally potassium oxide and hydrogen gas. KOH can cause severe eye and 

skin burns and if ingested can cause burns and perforations internally. Inhalation of the aerosol may lead 

to chemical pneumonitis and pulmonary edema. Prolonged or repeated skin contact may cause dermatitis. 

The American Conference of Governmental Industrial Hygienists (ACGIH) exposure assessment ceiling 

value is 2 mg/m3

 (NIH, 2011). 

CaF2 is produced in the Environmental Protection Process (EPP) as a result of treating fluoride bearing 

liquors with hydrated lime (calcium hydroxide). It is a gray to white powder that is only slightly soluble 

in water. It reacts with concentrated acids to liberate HF. The TLV and PEL are both published at 2.5 

mg/m3 as fluoride. It is considered of “little acute toxicity” and is stable unless heated to 12000

C or mixed 

with concentrated acids (NIH, 2011). 

6.2 PROCESS CHEMICAL RISK AND ACCIDENT SEQUENCES 

The IIFP workplace environmental, safety and health programs are intended to minimize the risk of 

chemical exposure from licensed material and other hazardous chemicals to employees, the public and the 

environment. This is accomplished through the controls resulting from the ISA where licensed materials 

are involved and through the implementation of the CPS Program. The Program will be documented in an 

implementation plan and in written procedures that ensure processes and operations comply with 

applicable federal and state regulations pertaining to chemical safety. The CPS Program incorporates and 

satisfies the requirements of the OSHA, “Process Safety Management of Highly Hazardous Chemicals,” 

(PSM) (CFR, 2009f). 

This section discusses chemical safety issues related to: 1) radiation risks of licensed materials, 2) 

chemical risks of licensed materials and hazardous chemicals produced from licensed material and 3) 

facility conditions that may affect the safety of licensed material resulting in an increased risk to workers, 

the public or the environment. In the PHA of the ISA, these chemical hazards, where applicable as part of 

licensed materials or affecting licensed materials, are treated with the same analysis rigor as radiological 

hazards and have included engineered controls or prevention measures to meet or exceed acceptable risk 

determined in the ISA Summary, Revision B. 

6.2.1 Process Descriptions 

The facility process descriptions are provided in the ISA Summary, Revision B Section 3. The 

descriptions provide a basic understanding of the chemical process hazards (including radiological 

hazards caused by, or involving, chemical accidents) and allow development of potential accident 

scenarios. Summaries of the process descriptions are also included in LA, Revision B Chapter 1. 
LA-IFP-001 Revision B CHAPTER 6 December 8, 2011 

Page 6-5

6.2.2 Consequences and Likelihoods of Accident Sequences 

An ISA has been performed as required by 10 CFR 70.62 (CFR, 2009b). The ISA Summary, Revision B 

provides a list of the accident sequences that have the potential to result in radiological and nonradiological releases of chemicals and provides estimates for the likelihood and consequence of each 

accident identified. The ISA Summary also identifies the engineering and/or administrative controls for 

each accident sequence of significance. These controls are intended to satisfy the Baseline Design Criteria 

(BDC) in 10 CFR 70.64 (CFR, 2009c) and performance requirements in 10 CFR 70.61 (CFR, 2009a) by 

applying defense-in-depth techniques to high-risk chemical release scenarios. The ISA provides sufficient 

quantities and types of controls so that engineered controls and prevention measures will satisfactorily 

perform their safety function and purpose when needed. 

Accident sequences involving licensed materials and those chemicals that may impact licensed materials 

have been analyzed in the ISA and are presented in the ISA Summary, Revision B. The accident 

sequences identified by the ISA were categorized into one of three consequence categories (high, 

intermediate or low) based on their radiological, chemical and/or environmental impacts. 

The radiological and chemical consequence severity limits for the high and intermediate categories, 

defined by 10 CFR 70.61 (CFR, 2009a), are presented in Table 6-1 “Chemical Consequence Severity 

Levels.” The ISA considers the potential interactions of process chemicals with confinement vessels and 

with process equipment in which initiating events incorporate releases of DUF6 from equipment, 

including vessels, pipes, valves and cylinders. Interactions between process chemicals and personnel are 

considered both in the ISA and during the preparation of facility operating procedures to include 

industrial safety practices. 

Table 6-1 Chemical Consequence Severity Levels (Defined by 10 CFR 70.61) 

Consequence Workers Offsite Public Environment 

High 

Radiological dose greater than 

1 Sv (100 rem) 

Radiological dose greater than 

0.25 Sv (25 rem) 

A criticality accident occurs 

30 mg soluble uranium intake 

Chemical exposure greater than 

AEGL-3 (for accident specific 

exposure time) 

Chemical exposure greater than 

AEGL-2 (30 minute exposure) 

A criticality accident occurs A criticality accident occurs 

Intermediate 

Radiological dose greater than 

0.25 Sv (25 rem) but less than 

or equal to 1 Sv (100 rem) 

Radiological dose greater than 

0.05 Sv (5 rem) but less than or 

equal to 0.25 Sv (25 rem) 

Radioactive release greater 

than 5,000 times 

10 CFR 20, Appendix B, 

Table 2 (CFR, 2009d) 

Chemical exposure greater than 

AEGL-2 but less than or equal 

to AEGL-3 (for accident 

specific exposure time) 

Chemical exposure greater than 

AEGL-1 but less than or equal 

to AEGL-2 (30 minute 

exposure) 

The measures to mitigate the consequences of accident sequences identified in the ISA Summary are 

consistent with protective actions described in Revision B of the IIFP Emergency Management Plan 

(EMP) and its implementing procedures. 
LA-IFP-001 Revision B CHAPTER 6 December 8, 2011 

Page 6-6

In addition to the chemical exposure criteria, the ISA considered the skin exposure to HF. In the absence 

of an authoritative quantitative standard for HF dermal exposure, the ISA considered that HF exposure 

consequences would be bounded by identification and use of Items Relied on for Safety (IROFS) for the 

consequences of the inhalation exposure pathway to the worker or the public. 

The ISA basis for HF exposure consequence analysis, prevention and mitigation is discussed in Section 

4.1.2 “Consequence Analysis” of the IIFP ISA Summary, Revision B. 

6.2.3 Chemical Release Scenario Techniques and Assumptions 

The techniques and assumptions used to estimate the concentrations or to predict the toxic “footprint” for 

potential releases of hazardous chemicals to workers and the public produced by licensed material, or by 

abnormal facility conditions that could affect the safety of licensed materials, are described in the 

following sections. 

6.2.3.1 Worker Exposure 

Any release from UF6 systems and/or cylinders at the IIFP Facility would predominately consist of HF, 

UO2F2 and potentially lesser quantities of UF6. Other sources of HF could result from by-product reaction 

of SiF4 and BF3 with water following a release. These releases would cause a visible cloud and a pungent 

odor. HF has a strong irritating odor that is discernable at concentrations of about 0.04 ppm (ATSDR, 

2009). The irritating effects of HF are typically intolerable at concentrations well below those that cause 

permanent injury or which produce escape impairing symptoms. 

Workers are trained in proper response actions, i.e., escape a release upon sensing initial HF effects. For 

the purpose of evaluating personnel exposure in cases where a worker would be expected to be in the 

immediate proximity of a release, worker exposures were assessed based on the amount of time required 

for the worker to conservatively evacuate the airborne material released from a hazardous material leak. 

Once a release is detected the worker is required by procedure and training to evacuate the area of 

concern. A conservative sufficient time is available for the worker to reliably detect and evacuate the area 

of concern to avoid permanent injury. 

Public exposures were estimated to last for 30-minutes duration. Acute Exposure Guideline Levels 

(AEGL) values have been used for HF, UF6 and hazardous chemical assessments (EPA, 2009a). Table 6-

2, “Chemical Consequence Values” shows the numeric values used as chemical consequence thresholds. 
LA-IFP-001 Revision B CHAPTER 6 December 8, 2011 

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Table 6-2 Chemical Consequence Values

Consequence Workers Offsite Public Environment 

Category 3 

High 

Soluble U intake > 75 mg 

HF > 170 ppm 

UF6 > 216 mg/m3

Soluble U intake > 30 mg 

HF >34 ppm 

UF6 >19 mg/m3

N/A 

Category 2 

Intermediate 

HF > 95 but < 170 ppm 

UF6 > 28 but < 216 mg/m3

HF> 1 but < 34 ppm 

UF6 > 3.6 but < 19 mg/m3

Radioactive release>5000 

times of 10 CFR 20, 

Appendix B, Table 2 

(CFR, 2009d) 

Category 1 

Low 

Accidents of lower radiological 

and chemical exposures than 

those above. 

Accidents of lower radiological 

and chemical exposures than 

those above. 

Radioactive releases with 

lower effects than those 

above. 

6.2.3.2 Public Exposure 

Potential exposures to the public were evaluated using conservative assumptions for both exposure 

concentrations and durations. Exposure was evaluated for consequence severity against chemotoxic, 

radiotoxic and radiological dose. Public exposures were estimated for durations of thirty (30) minutes. 

This is consistent with self protection criteria for UF6/HF plumes listed in NUREG-1140, “A Regulatory 

Analysis on Emergency Preparedness for Fuel Cycle and Other Radioactive Material Licensees,” (NRC, 

1988). 

6.2.4 Source Term and Dispersion Models 

The methodologies used to determine the source term are those prescribed in NUREG/CR-6410, “Nuclear 

Fuel Cycle Facility Accident Analysis Handbook,” (NRC, 1998) and supporting documents. The specific 

modeling methods utilized follow consistent and conservative methods for source term determination, 

release fraction, dispersion factors and meteorological conditions. For releases inside of buildings, 

conservative leak path fractions were assumed as recommended by NUREG/CR-6410. 

6.2.5 Description of Chemical Dispersion Models 

The computer code used in chemical consequence analyses is HGSYSTEM version 3.0. (NTIS, 1995). It 

is widely accepted by the nuclear industry as appropriate for chemical dispersion modeling. A more 

detailed description of HGSYSTEM analysis is provided in the ISA Summary, Revision B. 

6.2.6 Chemical Exposure Standards 

To quantify criteria of 10 CFR 70.61 (CFR, 2009a) for chemical exposure, standards for each applicable 

hazardous chemical must be applied to determine exposure that could endanger the life of a worker, lead 

to irreversible or other serious long term health effects in an individual and cause mild transient health 

effects to an individual. Exposure standards include the AEGLs established by the “National Advisory 

Committee for Acute Exposure Guideline Levels for Hazardous Substance,” (EPA, 2009a). The IIFP 

Facility uses the AEGL standard to assess the consequences of postulated chemical releases. The accident 

sequences resulting in chemical consequences exceeding the criteria in 10 CFR 70.61 involves the release 

of UF6 and its hydrolysis products HF and UO2F2. These accident sequences are presented in the ISA 

Summary, Revision B. 
LA-IFP-001 Revision B CHAPTER 6 December 8, 2011 

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In normal operations, AHF is produced as a result of the reaction between DUF6 and H2. The AHF 

product is transferred to storage vessels and ultimately to containers for sale of this by-product to 

customers. Potential exposure to HF for these processes is discussed in the ISA Summary, Revision B. 

6.3 ITEMS RELIED ON FOR SAFETY AND MANAGEMENT MEASURES 

This section describes the identification of chemical process IROFS and their associated management 

measures. 

6.3.1 Chemical Safety Approach 

The ISA Summary, Revision B describes the basis for providing successive levels of protection such that 

health and safety of employees and the public is ensured within the acceptable risks determined by the 

ISA structured risk analyses. Additionally, in many and most parts of the processes, safety is further 

assured by added measures through implementation of designed operational control features and the 

defense-in-depth engineering design philosophy. Section 6.3.2 below provides further description of 

defense-in-depth and operational control measures. 

In addition to the safe design features, the schemes employed to ensure safe operation of the facility 

include management measures that provide for the reliability of IROFS. These measures include a riskbased graded approach for the application of configuration management (CM), maintenance, procedures, 

training, audits/ assessments, emergency planning, incident investigation, human factors, records and 

reporting. Management measures are fully described in LA, Revision B Chapter 11 “Management 

Measures.” The IIFP Facility management is committed to identifying and correcting any unacceptable 

performance deficiencies and to maintain chemical process safety records. 

6.3.1.1 Chemical Process Safety Program 

The Chemical Process Safety (CPS) Program is applicable to the chemicals associated with the authorized 

activities described in LA, Revision B Chapter 1 and includes UF6, HF, as well as other hazardous 

chemicals associated with licensed material activities. The CPS Program provides oversight of the 

handling, use and storage of chemicals at the IIFP Facility. 

The CPS Program development, maintenance and oversight are the responsibility of the Environmental, 

Safety and Health (ESH) organization. Its implementation overlaps with several other disciplines 

including: Operations, Maintenance, Radiation Protection, Emergency Preparedness/Security, 

Environmental Protection and Industrial Safety/Industrial Hygiene. Prior to starting a new activity 

involving chemicals, a Job Hazards Analysis (JHA) is performed to ensure that the work is conducted 

safely and that appropriate training, authorizations and procedures are completed. This ensures that 

appropriate controls are in place for adequate protection of the general public and safe use by employees 

and that the use of chemicals does not create potential conditions that have not been evaluated in the ISA 

or could adversely affect the handling of licensed materials. Employees and contractors using hazardous 

materials are trained to ensure safe handling, use and disposal. The IIFP Site emergency response team is 

prepared to respond to various emergency conditions, including a chemical accident. 

ESH management reviews and approves JHAs prior to initial issuance. The review and approval is to 

affirm that the radiation, chemical, process, fire and explosion risks associated with the process or facility 

under evaluation are understood and that proper safety measures are in place. LA, Revision B Chapter 2 
LA-IFP-001 Revision B CHAPTER 6 December 8, 2011 

Page 6-9

“Organization and Administration” contains a description of the IIFP Facility Organization, including the 

responsibilities of the ESH Manager. 

The IIFP Facility satisfies the OSHA Process Safety Management (PSM) initial requirement on process 

safety information through the ISA work for NRC licensing and the CPS Program. NRC requirements for 

maintaining and updating process safety information are also utilized to maintain compliance with this 

aspect of the PSM requirements. For chemical hazards associated with materials that have been separated 

from licensed materials, the IIFP Facility will apply standard OSHA PSM requirements to evaluate and 

control the hazard and risk associated with these chemicals. The IIFP Facility uses a graded approach in 

meeting requirements of the PSM standard by identifying applicable areas requiring PSM and applying 

the program to those specific areas based on the process safety information. 

The IIFP Facility will develop a thorough, orderly, systematic approach for identifying, evaluating and 

controlling processes involving highly hazardous chemicals. An implementation plan will be prepared 

and used by the IIFP Facility to develop procedures for meeting requirements in each of the program 

elements and applicable plant process areas. The program development and implementation will be 

incorporated into other plant-related systems, such as emergency procedures and response, contractor 

orientation/training and change management as appropriate. 

Procedures and training programs will be developed and utilized by the IIFP Facility for process safety, 

plant operations and maintenance. CPS requirements will be addressed in plant ESH procedures and 

incorporated into specific operation and maintenance procedures. 

The mechanical integrity element of OSHA PSM requires that equipment used to process, store or handle 

highly hazardous chemicals be designed, installed and maintained to minimize the risk of release of such 

chemicals. The IIFP Facility will have a mechanical integrity program in place to assure the continued 

integrity of process equipment. The components of the mechanical integrity program include: 

• Identification and categorization of equipment and instrumentation 

• Development of written maintenance procedures 

• Training for process maintenance activities 

• Inspection and testing 

• Correction of deficiencies in equipment that are outside acceptable limits defined by the process 

safety information 

• Use of the appropriate level of quality assurance to maintain mechanical integrity for safety 

controls and process systems 

Portions of OSHA PSM mechanical integrity requirements are met through implementation of programs 

designed to comply with the IIFP ISA, Revision B requirements. Specific baselines and periodic tests and 

inspections for mechanical integrity are included in the facility Preventive Maintenance Program and 

procedures. 

The IIFP Facility takes immediate action when there is a leak or accident involving highly hazardous 

chemicals. The IIFP Facility establishes and implements an Emergency Management Plan in accordance 
LA-IFP-001 Revision B CHAPTER 6 December 8, 2011 

Page 6-10

with the provisions of 29 CFR 1910.38(a), “Emergency Action Plans,” (CFR, 2009h) including 

procedures for handling small releases. The IIFP Facility incorporates applicable provisions of the 

“Hazardous Waste and Emergency Response Standard,” 29 CFR 1910.120(a), (p) and (q) (CFR, 2009i) 

into the EMP through the Emergency Management Plan Implementing Procedures (EPIPs). 

A Spill Prevention, Control and Countermeasure (SPCC) Plan will be implemented during construction to 

minimize both the possibility of spills of hazardous substances and to minimize the environmental impact 

in the event that spills occur. The SPCC Plan will continue to be in effect throughout the operation of the 

facility. 

The IIFP Facility maintains an active Cylinder Management Program to maintain optimum storage 

conditions in the cylinder yard to monitor cylinder integrity by conducting routine inspections for 

breaches and to perform cylinder maintenance and repairs to cylinders and the storage yard as needed. 

Handling and storage procedures and practices are adopted at the IIFP Facility to mitigate adverse events 

by either reducing the probability of an adverse event or reducing the consequence should an adverse 

event occur. 

Chemical Evaluation and Approval

Prior to new hazardous materials being brought onsite or being used in an activity, the materials are 

approved through a formal process initiated when a request for procurement of a new chemical is 

submitted. Before a new chemical is ordered, the requester must obtain approval from the Chemical 

Review team which is comprised of a representative of the ESH Organization, an area manager and others 

as deemed appropriate by the ESH representative. The ESH representative leads the review and is a 

qualified chemical safety reviewer. The process for approval includes reviewing the health and safety 

risks of the chemical as well as appropriate handling, storage and disposal information. Every effort is 

made to limit the amount of hazardous chemicals used, including identifying feasible alternative 

chemicals or processes. The ESH representative coordinates this effort with representatives from 

Environmental Protection, Industrial Safety/Industrial Hygiene and Radiation Protection. The formal 

approval process consists of evaluations for the physical, health and fire/explosive hazards as well as the 

potential impact on handling of licensed material. The results of this approval process may dictate the 

implementation of some or all of the following for assurance of chemical process safety: 

• New procedures or changes to existing procedures 

• Maintenance programs for equipment 

• Configuration Management controls 

• Addition of Material Safety Data Sheet(s) to safety information database 

• Emergency planning modifications 

• Training requirements 

The procedure for approving new hazardous materials being brought on-site or used in a process is 

applicable to both employees and contractors. If a contractor desires to use a new chemical, the contractor 

must notify the IIFP Facility point of contact and the IIFP Facility new chemical approval procedure is 

initiated. If an existing hazardous chemical is to be used in a new plant process or affects an existing 

process involving an IROFS where that chemical has not been used previously, the change would also be 
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evaluated through the 10 CFR 70.72, “Facility Changes and Change Process,” (CFR, 2009e), as described 

in LA, Revision B Chapter 11. 

Labeling and Identification

Hazardous materials containers or conveyance systems are labeled and identified to comply with 

applicable regulations. The proper identification of hazardous materials decreases the likelihood and 

potential negative consequences of improper use, handling or disposal of those materials. 

The hazards of chemicals are identified for personnel through the MSDSs. These documents will be 

available in the workplace. 

Chemical Inventories

Where feasible, chemical inventories at the IIFP Facility are maintained below the threshold quantities set 

forth in OSHA 29 CFR 1910.119, “Process Safety Management of Highly Hazardous Chemicals,” (CFR, 

2009f) and the Environmental Protection Agency (EPA) 40 CFR 68, “Chemical Accident Prevention 

Provisions,” (CFR, 2009g). Inventories of chemicals are tracked through the procurement process. In 

addition, the EMP contains an inventory, including amounts and locations, of bulk chemicals as required 

by EPA’s “Emergency Planning and Community Right-to-Know Act,” (EPCRA) Section 312, Tier II 

(EPA, 2009b). The EMP which is updated annually and the MSDSs are provided to applicable offsite 

responders. Process chemicals such as HF and other fluorine bearing chemicals are typically at inventory 

levels above threshold quantities and are controlled under the provisions of “Process Safety 

Management,” defined in 29 CFR 1910.119 (CFR, 2009f). Additionally, the IIFP Facility has an 

agreement with the State of New Mexico that limits the maximum amount of certain depleted uranium 

materials and certain containers that are permitted to be held in on-site inventories (NMED, 2009). A 

copy of the agreement has been provided to the NRC to be incorporated into Revision B of the IIFP 

Facility LA. 

Hazardous Chemicals and Chemical Interactions

Chemicals utilized at the IIFP Facility that contain licensed material or have the potential to affect 

licensed material, either directly or indirectly, are evaluated to determine the consequence level for a 

particular accident sequence. The main chemicals of concern at the IIFP Facility are DUF6, BF3, SiF4 and 

AHF. If UF6 is released into the atmosphere, the uranium compounds and HF that are formed by reaction 

with moisture in the air are chemically toxic. Uranium is a heavy metal that, in addition to being 

radioactive, can have toxic chemical effects primarily on the kidneys if it enters the bloodstream by 

means of ingestion or inhalation. HF is an extremely corrosive gas that can damage the lungs and cause 

death if inhaled at sufficiently high concentrations (see Section 6.1). Similarly, the formation of HF 

occurs with releases of SiF4 and BF3 but no radiological component or uranium toxicity is associated with 

such releases. 

6.3.1.2 Materials of Construction, Sizing of Equipment, System Fabrication and Process Control 

Schemes 

The design of the chemical process systems includes numerous controls for maintaining safe conditions 

during operations. These controls include but are not limited to the following: 

• Managing the arrangement, size and physical integrity of material containers and processes 
LA-IFP-001 Revision B CHAPTER 6 December 8, 2011 

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• Selecting and using materials compatible with process chemicals 

• Providing inherently safe operating conditions (such as UF6 confinement) 

• Providing process interlocks, controls and alarms within the chemical processes 

These facility and equipment features help prevent chemical releases. Process piping and components 

(such as reaction vessels, conveyors, traps, vents, etc.) is maintained safe by limits placed on their 

operating parameters. 

Materials of Construction

Interactions between process equipment and process fluids are considered in the design of the IIFP 

Facility. The IIFP Facility will utilize materials of construction throughout the process and operations 

areas that are compatible and/or are corrosion resistant to UF6, HF, SiF4 and BF3. The materials of 

construction are also compatible with the process operational physical parameters of pressure and 

temperature accordingly. The materials of construction meet the applicable standard engineering 

specifications required by the International Building Code (IBC, 2009) and/or other building codes and 

their use is consistent with standard industry practice for processing UF6, HF, SiF4 and BF3. 

Standard steel or Monel containers, valves and piping are used at the IIFP Facility for transport, 

processing and storage of UF6 (ANSI, 2001). These containers are appropriate due to the resistance of the 

materials to corrosion by UF6. The DUF6 cylinders, used for transport and storage, are painted to resist 

corrosion from atmospheric conditions. The cylinders are also inspected on a routine basis to assess 

corrosion. The storage and transport containers for HF, SiF4 and BF3 are specified to be corrosionresistant to these chemicals under all normal and anticipated abnormal environments. 

Sizing of Equipment

The sizing of process equipment is based on the amount of material to be used in the process. The design 

of preventive and/or mitigation features is based on conservative assumptions to allow for unusual 

conditions. For example, tanks that contain bulk chemicals are designed for more capacity than the 

maximum volume expected during normal operations. In addition, overflow alarms and mitigation 

devices (such as curbs, sumps, overflow tanks), are available for use during upset conditions and provide 

conservative margins of safety for spill containment. 

System Fabrication

Within the IIFP Facility, systems are fabricated with safety and physical integrity as a priority. Materials 

of construction are chosen to avoid or minimize corrosion. Fabrication operations such as machining, 

drilling, welding, heating and grinding are established to prevent and/or mitigate hazards to the worker 

and minimize releases to the public and the environment. Preventive maintenance is routinely scheduled 

for replaceable parts. The systems are designed to provide easy access for maintenance. 

Process Control Schemes

Process control schemes are chosen with safety as a priority. The process control schemes that are 

associated with IROFS are described in the ISA Summary, Revision B. Minimum impacts to the 

environment, safety and health are addressed through an engineering design philosophy that includes: 
LA-IFP-001 Revision B CHAPTER 6 December 8, 2011 

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• Minimum necessary inventories of chemicals and subsequent minimum source terms 

• Secondary containment of potential chemical hazards 

• Redundancy on selected key safety systems 

• Defense-in-depth layers of protection with first priority on engineered controls 

• Multi-stage treatment devices configured in series 

6.3.2 Chemical Process Safety Controls 

The IIFP ISA accident analysis methodology considers and evaluates the likelihood and consequences of 

accident sequences involving hazardous chemicals that contain licensed materials or affect licensed 

materials. Where unmitigated accidents are unacceptable risks, IROFS are identified and developed 

including engineered controls and administrative controls to prevent or mitigate chemical process risks. 

The IIFP ISA Summary, Revision B describes the accident sequence, chemical consequence evaluation 

the hazard being mitigated, risk category and the function of the IROFS. 

In addition to IROFS, many operational control features (safeguards which are not considered IROFS) are 

incorporated as defense-in-depth to support worker safety. Some of the more important operational 

control safeguards are identified in Section 3.1 of the ISA Summary Revision B. Items such as lab hoods, 

eye wash stations and safety showers are established as part of a standard industrial safety program and 

were assumed to be available as part of the evaluations conducted in the ISA. Safeguards are also applied 

to process systems that involve hazardous chemicals that have been separated from licensed materials. 

A defense-in-depth approach is followed during the design of chemical process systems. The ISA 

Summary, Revision B identifies a number of IROFS and inherent safeguards for protecting against or 

mitigating process material releases. Many of these reduce the likelihood or severity of hazardous 

material releases from process equipment. Others help the operators respond more quickly and/or 

efficiently to limit the effects of releases of hazardous material. These IROFS and safeguards include, in 

order of preference, passive controls (such as curbs around chemical tanks), active engineered controls 

(such as high temperature shutdown interlocks) and administrative controls (such as operator training and 

approved written procedures). Some safeguards, such as gas alarm systems, provide a mitigation function 

by alerting operators to evacuate the facility, thus limiting radiation and chemical worker exposure during 

an event. Examples of chemical hazard design, including both IROFS and safeguard level controls, 

include the following: 

• UF6 cylinders are locked inside a containment-type autoclave when being heated or fed to the 

process. 

• UF6 cylinders are not lifted or transported when the material inside the cylinder is in a liquid 

state. 

• Areas where HF is collected or stored and where significant HF potential source terms are 

involved, such as storage tanks and loading equipment, are in a containment-type building. The 

containment building is not totally leak tight, but provides for substantial mitigation of released 

vapors by initiation of water spray inside the building. 

• Exhaust hood and capture systems are located in selected general areas where there are hazardous 

materials to provide back-up emergency control and evacuation in the event of a leak. 
LA-IFP-001 Revision B CHAPTER 6 December 8, 2011 

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• Process areas where chemicals or hazardous materials are stored or used are provided with sealed 

concrete pads, including containment dike walls, to contain any one full storage or process vessel. 

• Lab hoods and sinks are provided to drain/vent hazardous chemicals. 

• Area eye wash stations and showers are installed in strategic locations to mitigate the 

consequences of exposures. 

• Area fluoride and radiation detection systems and alarms are strategically located to support 

worker evacuations during a hazardous chemical release. 

6.3.3 Chemical Process Safety Management Measures 

Management measures, including those for chemical process IROFS, are discussed in LA, Revision B 

Chapter 11 and are implemented to assure the reliability and availability of chemical process related 

IROFS. 

The safety management measures provide the overriding management oversight and assurance that the 

CPS Program is maintained and functions properly. The IIFP Facility applies management measures in a 

graded approach based on unmitigated risks as described in the ISA Summary. Based upon criteria 

defined in approved written procedures, the relative importance of IROFS is determined and the 

appropriate types and numbers of management measures are assigned to assure the IROFS are functional 

when needed. 

6.3.3.1 Procedures to Ensure Reliable Operation of Engineered Controls 

The IIFP Facility maintains approved written procedures to ensure reliable operation of engineered 

controls (such as inspection and testing procedures and frequencies, calibration programs, functional tests, 

corrective and preventive maintenance programs and criteria for acceptable test results). Additionally, 

programs and procedures address construction and configuration controls to ensure CM during design and 

construction. 

6.3.3.2 Procedures to Ensure Proper Implementation of Administrative Controls 

The IIFP Facility maintains approved written procedures to ensure administrative controls are correctly 

implemented (such as employee training and qualification in procedures, refresher training, safe work 

practices, development of procedures and training program evaluation). 

6.4 REQUIREMENTS FOR NEW FACILITIES 

The IIFP Facility is a new chemical process facility. Revision B of the LA, Chapter 3 “Integrated Safety 

Analysis” and Revision B of the ISA Summary describe the methodology for satisfying the principles of 

the facility Base Design Criteria (BDC) in 10 CFR 70.64 (CFR, 2009c). The ISA Summary describes how 

the chemical safety BDC is applied in establishing the design principles, features and control systems of 

the new process. 
LA-IFP-001 Revision B CHAPTER 6 December 8, 2011 

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The IIFP Facility is designed with the defense-in-depth approach for protecting against chemical 

accidents. In accordance with 10 CFR 70.64(a)(5) (2009c) and NUREG-1601, Section 2-4 (NRC, 1997a), 

the design provides for adequate protection against chemical risks produced from licensed material, 

facility conditions that affect the safety of licensed material and hazardous chemicals produced from 

licensed material. For chemical process safety, the facility design considered the following: 

• Preference for the selection of engineered controls over administrative controls to increase overall 

system reliability 

• Preference for prevention over mitigation and operator intervention 

• Operational design features that enhance safety by adding extra measures and reducing challenges 

to IROFS 

There are a number of operational design features that are not IROFS and no credit is taken for these 

features in the risk-based ISA. However, as extra measures in addition to IROFS, these features do help 

ensure chemical process safety. These features include robust and chemical compatible equipment, 

piping, connections and valves that confine hazardous chemicals. For example: 1) purge and evacuation 

(P&E) systems and equipment are installed in the DUF4 and FEP Process Buildings to provide for 

purging equipment and piping with dry nitrogen and evacuating the residual hazardous chemicals prior to 

opening the equipment or piping for maintenance, 2) physical barriers include fire walls as determined by 

the Fire Hazards Analysis described in LA, Revision B Chapter 7 “Fire Safety,” 3) vented hoods are 

appropriately provided in the decontamination and maintenance areas, 4) isolation and check valves are 

used in piping containing hazardous chemicals and 5) temperature and pressure controls, sensors with 

alarm points and control valves are appropriately included that provide data and operational controls for 

assisting in the safe operation of the processes. 

The IIFP Facility is not proposing any facility-specific or process-specific relaxations or additions to the 

Basic Design Criteria of 10 CFR 70.64 (2009c). 
LA-IFP-001 Revision B CHAPTER 6 December 8, 2011 

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REFERENCES 

ANSI, 2001 American National Standards Institute Inc., “Nuclear Materials: Uranium Hexafluoride— 

 Packaging for Transport,” ANSI N14.1-2001, 2001. 

ATSDR, 2009 Agency for Toxic Substances & Disease Registry, "Medical Management Guidelines for 

 Hydrogen Fluoride," 2009. 

CFR, 2009a Title 10, Code of Federal Regulations, Section 70.61, "Performance Requirements," U.S. 

 Nuclear Regulatory Commission, 2009. 

CFR, 2009b Title 10, Code of Federal Regulations, Section 70.62," Safety Program and Integrated 

 Safety Analysis," U.S. Nuclear Regulatory Commission, 2009. 

CFR, 2009c Title 10, Code of Federal Regulations, Section 70.64, "Requirements for New Facilities 

 or New Processes at Existing Facilities," U.S. Nuclear Regulatory Commission, 2009. 

CFR, 2009d Title 10, Code of Federal Regulations, Section 20, "Standards for Protection Against 

 Radiation," U.S. Nuclear Regulatory Commission, 2009. 

CFR, 2009e Title 10, Code of Federal Regulations, Section 70.72, "Facility Changes and Change 

 Process," U.S. Nuclear Regulatory Commission, 2009. 

CFR, 2009f Title 29, Code of Federal Regulations, Section 1910.119, "Process Safety Management of 

 Highly Hazardous Chemicals," U.S. Occupational Safety and Health Administration, 

 2009. 

CFR, 2009g Title 40, Code of Federal Regulations, Section 68, "Chemical Accident Prevention 

 Provisions," U.S. Environmental Protection Agency, 2009. 

CFR, 2009h Title 29, Code of Federal Regulations, Section 1910.38(a), "Emergency Action Plans," 

 U.S. Occupational Safety and Health Administration," 2009. 

CFR, 2009i Title 29, Code of Federal Regulations, Section 1910. 120, "Hazardous Waste and 

 Emergency Response Standard," U.S. Occupational Safety and Health Administration, 

 2009. 

EPA, 2009a U.S. Environmental Protection Agency, "National Advisory Committee for the 

 Development of Acute Exposure Guideline Levels (AEGLs) for Hazardous Substances," 

 2009. 

EPA, 2009b U.S. Environmental Protection Agency, "Emergency Planning and Community Right-to- 

 Know Act (EPCRA)," Section 312, Tier II, 2009. 

IBC, 2009 International Code Council, International Building Code, 2009. 

NIH, 2011 National Institute of Health, Specialized Information Services, "U.S. National Library of 

 Medicine," Website www.hazmap.nlm.nih.gov, 2011. 
LA-IFP-001 Revision B CHAPTER 6 December 8, 2011 

Page 6-17

NMED, 2009 New Mexico Environmental Department, "Memorandum of Agreement Between 

 International Isotopes, Inc. and New Mexico Environmental Department," 2009. 

NRC, 1988 U.S. Nuclear Regulatory Commission, "A Regulatory Analysis on Emergency 

 Preparedness for Fuel Cycle and Other Radioactive Material Licensees," NUREG-1140, 

 1988. 

NRC, 1997a U.S. Nuclear Regulatory Commission, "Chemical Process Safety at Fuel Cycle 

 Facilities," NUREG-1601, 1997. 

NRC, 1997b U.S. Nuclear Regulatory Commission, "Review of Models Used for Determining 

 Consequences of UF6 Release," NUREG/CR-6481, 1997. 

NRC, 1998 U.S. Nuclear Regulatory Commission, "Nuclear Fuel Cycle Facility Accident Analysis 

 Handbook," NUREG/CR-6410, 1998. 

NRC, 2001 U.S. Nuclear Regulatory Commission, "Integrated Safety Analysis Guidance Document," 

 NUREG-1513, 2001. 

NRC, 2002 U.S. Nuclear Regulatory Commission, “Standard Review Plan for the Review of a 

 License Application for a Fuel Cycle Facility,” NUREG-1520, 2002. 

NTIS, 1995 National Technical Information Service, HGSYSTEM version 3.0, “Dispersion Models 

 for Ideal Gases,” Shell Research Ltd. Thornton (United Kingdom), 1995. 

ORNL, 2000 Oak Ridge National Laboratory, U.S. Department of Energy, “Thermal Stabilization of 

 233UO2, 233UO3 and 233U3O8” under contract DE-AC05-00 OR22725, 2000.