>EPA
United States
Environmental Protection
Agency
Air And Radiation (ANR-460)
Research And Development
(MD-13)
EPA 520/1-91-010-1
May 1991
Radiation And
Mixed Waste Incineration
Background Information Document
Volume 1: Technology
-------
-------
Radiation And
Mixed Waste Incineration
Background Information Document
Volume 1: Technology
control technology center
Printed on Recycled Paper
-------
-------
EPA 520/1-91-010-1
May 1991
BACKGROUND DOCUMENT ON
RADIOACTIVE AND MIXED WASTE INCINERATION
VOLUME I - TECHNOLOGY
Work Assignment Manager
Madeleine Nawar
Office of Radiation Programs
U.S. Environmental Protection Agency
401 M Street, S.W.
Washington, DC 20460
Prepared under:
Contract No. 68-D9-0170
Prepared for:
Control Technology Center
U.S. Environmental Protection Agency
Research Triangle Park, North Carolina 27711
-------
DISCLAIMER
Mention of any specific product or trade name in this report does not imply an endorsement or
guarantee on the part of the Environmental Protection Agency.
-------
PREFACE
This project to provide technical guidance on radioactive and mixed waste (low-level
radioactive contaminated waste) incineration was funded by the Control Technology Center
(CTC). Work on this project was primarily directed and performed by EPA's Office of
Radiation Programs (ORP). This cooperative effort was established to provide necessary
technical expertise and funding to compile information needed by air pollution control agencies
considering permits for these incinerators. '
The CTC was established by EPA's Office of Research and Development (ORD) and
Office of Air Quality Planning and Standards (OAQPS) to provide technical assistance to state
and local air pollution control agencies. The two sponsoring organizations for the CTC are the
Air and Energy Engineering Research Laboratory (ORD) and the Emission Standards Division
(OAQPS). Three levels of assistance can be accessed through the CTC. First, a CTC
HOTLINE has been established to provide telephone assistance, on matters relating to air
pollution control technology. Second, more in-depth engineering assistance can be provided
when appropriate. Third, the CTC can provide technical guidance through the publication of
technical guidance documents, development of personal computer software, and presentation of
workshops on control technology matters. To access CTC services, call the CTC HOTLINE -
(919) 541-0800 or (FTS) 629-0800.
Technical Guidance projects, such as this one, focus on topics of national or regional
interest that are identified through contact with state and local agencies. In this case, the State
of New Mexico contacted the CTC and requested technical assistance with regard to permit
applications for mixed waste incinerators. It became evident that incineration of radioactive and
mixed wastes is being considered or implemented as a waste volume reduction method at a
number of facilities handling nuclear material. The CTC contacted ORP to discuss the
possibility of a joint venture whereby CTC would provide funding and ORP would provide
technical expertise and project management. This technical guidance document is the result of
that cooperative effort.
iii
-------
-------
ACKNOWLEDGEMENT
This document was prepared for EPA's Control Technology Center (CTC), Research Triangle
Park, North Carolina, by the Office of Radiation Programs (ORP), with support from Sanford
Cohen & Associates, Inc. (SC&A), of McLean, Virginia.
ORP wishes to thank the following individuals for their technical assistance and review
comments on the drafts of this report: especially Bob Blaszczak (CTC Co-Chair), Jeff Telander
(OAQPS), Irma McKnight (ORP-Program Management Office), Martin Halper (Director,
Analysis and Support Division [ASD], ORP), Robert Dyer (Chief Environmental Studies &
Statistics Branch, [ESSB] ASD, ORP), Ben Hull (ESSB/ASD), Lynn Johnson (ESSB/ASD),
Hank May (EPA-Region 6, Radiation Programs), Stan Burger (EPA-Region 6, RCRA Permits
Branch), Lewis Battist (ORP-ASD), Bill Blankenship, Gale Harms and Albion Carlson (New
Mexico, Air Quality Bureau); and Stephen Cowan, Betsy Jordan and Leanne Smith (DOE-HQ,
Office of Waste Operations, Environmental Restoration and Waste Management).
-------
-------
Table of Contents
ABSTRACT . . xv
1. Overview of Radioactive and Mixed Waste Incineration Experience . ..... 1-1
1.1 Radioactive and Mixed Waste Characteristics . . . . 1-1
1.1.1 Low-Level Radioactive Waste ..................... 1-2
1.1.2 Transuranic Waste 1-6
1.1.3 Mixed Waste 1-7
1.1.4 Incinerable Waste 1-10
1.2 Combustion Process and Radionuclide Emissions . . .''..1-15
1.2.1 Radionuclide Airborne Emissions 1-15
1.2.2 Radiological Properties of Ashes and Residues 1-19
1.3 Incinerator Population . . '....' 1-24
1.4 Operational Incinerator Emissions 1-36
1.4.1 DOE Incinerators 1-36
1.4.2 Commercial Incinerators 1-59
1.4.3 Institutional Incinerators 1-63
1.4.4 Studsvik Incinerator 1-65
1.5 Operations and Maintenance Practices and Procedures . 1-67
1.6 Regulatory Requirements ........ 1-68
1.6.1 Nuclear Regulatory Commission Licensing 1-68
1.6.2 Resource Conservation and Recovery Act
(RCRA) Requirements 1-71
1.6.3 State Regulations 1-72
References 1-75
2. Technologies for Controlling Incinerator Processes
and Radionuclide Emissions . .2-1
2.1 Process Control Technology 2-1
2.2 Process Monitoring Technology 2-2
2.3 Emission Control Technology 2-8
Vll
-------
Table of Contents (Continued)
2.3.1 Removal of Particulates .2-15
2.3.2 Removal of Gases . . , . 2-22
2.4 Capital and Operating and Maintenance Costs 2-24
2.5 Operations and Maintenance Concerns . 2-25
2.5.1 Pretreatment . .2-25
2.5.2 Feed System 2-25
2.5.3 Combustion Chamber 2-26
2.5.4 Air Pollution Control System 2-28
2.6 Incinerator Effectiveness 2-31
2.7 Incinerator Reliability .2-33
References • • -2-35
3. Technologies for Monitoring Incineration and Radionuclide
Airborne Emissions . . 3-1
3.1 Radionuclide Airborne Emissions Monitoring Technology . 3-1
3.1.1 Stack Off-Gas Sampling Systems 3-2
3.1.2 Real-Time Radiation Monitoring Systems 3-14
3.1.3 Indirect Radiation Monitoring Methods 3-16
3.1.4 Instrumentation Detection Limits 3-18
3.2 Radiation Process Monitoring Technology Description,
Principle of Operation, and Applications 3-25
3.3 Applicability of Non-Radioactive Emissions Stack
Monitoring Methods to Radionuclides 3-26
3.4 Monitoring Radionuclide Concentration in Incinerator Ash ....... 3-27
References 3-30
4. Consideration of Incinerator Accident and Abnormal
Operation Scenarios 4-1
4.1 Example Analyses of Incinerator Accident Scenarios 4-4
4.1.1 Scientific Ecology Group 4-4
4.1.2 Rocky Flats 4-6
Vlll
-------
Table of Contents (Continued)
4.1.3 Duke Power Company 4-8
References .4-14
5. Comparison of Incineration with Other Volume Reduction
Technologies 5-1
5.1 Sorting 5-3
5.2 Shredding 5-3
5.3 Compaction 5-3
5.4 Supercompaction 5-4
5.5 Storage for Decay 5-4
5.6 Combustion 5-4
References • • • 5-7
6. Summary 6-1
6.1 Report Objective 6-1
6.2 Incineration . 6-1
6.3 Relevant Issues . . . 6-4
6.3.1 Waste Acceptance Criteria 6-4
6.3.2 Incinerator Operations 6-6
6.3.3 Stack Monitoring 6-8
6.3.4 Radiological Risk Assessment 6-9
6.3.5 Airborne Radionuclide Emissions 6-10
Appendices
Appendix 1 NRC Incineration Guidelines for Material Licensees Al-1
Appendix 2 Nuclear Regulatory Commission Outline for Safety Related Topics
Design and Operation of Low-Level Radioactive Waste Incinerator . A2-1
Appendix 3 Excerpts from Illinois Regulations A3-1
Appendix 4 Incinerator Control Functions ..... .... . .... .... , A4-1
Appendix 5 Incinerator Monitoring Subsystems A5-1
Appendix 6 Cost Elements A6-1
Appendix 7 General Operations Problems and Preventive Maintenance Action . . A7-1
IX
-------
List of Tables
Table Numbers
1-1 LANL Typical Low-Level Radioactive Waste Generation and
Disposal Reflecting Past Cumulative Practices . 1-3
1-2 LLW Generators That Incinerated Waste in 1984 1-5
1-3 Waste Form Distribution and Incineration Reported by
Institutional Facilities 1-6
1-4 LANL Total Inventories of Retrievable TRU Waste Through 1987 1-8
1-5 Radionuclide Composition and Waste Mix of Buried and
Retrievably Stored TRU Wastes Reflecting Past Practices
at LANL 1-9
1-6 Approximate Distribution and Chemical Constituent Content
of Mixed Waste Forms 1-11
1-7 Estimated Yearly Mixed Waste Volume and Mass Generation
Rate by Physical Forms for LANL 1-12
1-8 Summary Characterization of Waste Volumes, Radiological
Properties, and Inventory at LANL . . . 1-14
1-9 Typical Distribution of Ash in Incinerator Components 1-20
1-10 Typical Radionuclide Distribution in Incinerator Ash . 1-22
1-11 Status of Selected U.S. Radioactive and Mixed Waste
Incinerators 1_33
1-12 International Operational Large Scale Incinerators 1-35
1-13 Rocky Flats Fluidized-Bed Incinerator Emissions 1-39
1-14 Rocky Flats Fluidized-Bed Incinerator Stack Radionuclide
Concentrations 1-39
1-15 LANL TRU Controlled Air Incinerator Emissions 1-41
-------
List of Tables (continued)
Page
1-16 LANL TRU Controlled Air Incinerator Stack Radionuclide
Concentrations . .1-41
1-17 LANL Bldg-37 (Including CAI) Pu-239 Stack Releases ............. .1-43
1-18 LANL Bldg-37 (Including CAI) Mixed Fission Products
(Beta) Stack Releases 1-44
1-19 LANL Controlled Air Incinerator Radioactive Throughputs . . . 1-46
1-20 Oak Ridge TSCA Incinerator Emissions and Waste Feed
Radioactivity for 1988 1-47
1-21 Oak Ridge TSCA Incinerator Stack Radionuclide Concentrations ........ 1-48
1-22 Brookhaven National Laboratory Low-Level Radioactive Waste
Emissions .1-49
1-23 Brookhaven National Laboratory Low-Level Radioactive Waste
Monthly Incinerator Emissions for 1987-1989 1-50
1-24 Brookhaven National Laboratory Low-Level Radioactive Waste
Incinerator Stack Concentrations .1-52
1-25 Idaho Engineering Laboratory WERF Incinerator Emissions 1-52
1-26 Idaho Engineering Laboratory WERF Incinerator Monthly
Emissions and Processed Waste Volumes 1-54
1-27 Idaho Engineering Laboratory WERF Incinerator Low-Level
Radioactive Waste Radionuclide Concentrations 1-55
1-28 Idaho Engineering Laboratory WERF Incinerator Stack
Concentrations . .... . ... .1-57
1-29 Idaho Engineering Laboratory WERF Incinerator Overall
Decontamination Factor 1-57
1-30 Savannah River Site Beta-Gamma Incinerator Emissions 1-58
XI
-------
List of Tables (continued)
1-31 Savannah River Site Beta-Gamma Incinerator Processed Waste
Volume and Activity: 1986-1988 . . . . 1-60
1-32 SEG Incinerator Waste, Emissions, Ash Radionuclide
Distribution for 1989 1-61
1-33 SEG Incinerator Atack Wmissions - 4th Quarter 1989 1-62
1-34 Advanced Nuclear Fuels Solid and Liquid Waste Volumes
and Uranium Mass 1-64
1-35 Effluent Release Rates for Low-Level Radioactive Waste
Incinerators - 1984 1-66
1-36 Radionuclide Emissions from the Swedish Studsvik Incinerator
Facility 1-66
2-1 Incineration System Control Functions .2-3
2-2 Incinerator Monitoring Subsystems 2-9
3-1 Summary of Stack Monitoring System Response 3-19
4-1 Activity Releases - Worst Case Accidents Duke Power
Company Incinerator 4-9
5-1 Volume Reduction Factors of Selected Technologies 5-6
Xll
-------
List of Figures
Figure
Numbers
Page
1-1 The Los Alamos Controlled Air Incinerator 1-25
1-2 The Oak Ridge Toxic Substances Control Act Incinerator 1-26
1-3 The Rocky Flats Fluidized Bed Incinerator 1-27
1-4 The INEL Waste Experimental Reduction Facility 1-28
1-5 The Savannah River Beta-Gamma Incinerator 1-29
1-6 The INEL PREPP Incinerator 1-30
1-7 The Scientific Ecology Group Incinerator 1-31
3-1 Typical Radioactive Airborne Emission Sampling System . 3-4
3-2 Conceptual Diagram Showing Stack Monitor Location and
Sampling Layout 3-5
3-3 Typical EPA Particulate Airborne Emission Sampling System 3-7
3-4 Typical EPA Volatile Organic Sampling System 3-8
3-5 Typical Isokinetic Sampling Probe . . .3-10
5-1 Volume Reduction Logical Process 5-2
6-1 Generic Incineration Flowsheet .6-3
Exhibits
1 Combustible Mixed Waste Volumes
2 Barnwell Rate Schedule
3 Half-Lives of Selected Radionuclides
xm
-------
-------
ABSTRACT
This background document, consisting of Volume I - Technology and Volume H - Risks of
Radiation Exposure, was prepared for the EPA Office of Radiation Programs as part of an EPA
Control Technology Center project to assist the State of New Mexico Environmental
Improvement Division/ Air Quality Bureau. It provides a broad look at technology issues
surrounding the incineration of radioactive and mixed wastes. It is intended to highlight major
considerations and to provide direction that would enable the reader who must deal in depth with
incineration to focus on and seek specific information on concerns appropriate to a particular
situation. It is not a comprehensive text on incinerator design, use, or regulation. The
information presented in this report was gathered by telephone contacts with operators of existing
incinerators, site visits, agency contacts, and literature searches. This report presents a
distillation of the material deemed to be most relevant; it includes only a small fraction of the
total amount of information collected. Wherever possible, actual operating data have been used
to illustrate principles, however, inconsistencies in operational data acquisition have resulted in
very limited availability of data that can be used for general assessment or purposes of
comparison. Even though the existing data base on operations and resulting emissions and ash
residues from radioactive waste incinerators is still quite small, it has been demonstrated that
incineration can achieve significant volume reductions for radioactive waste. Individual
incinerator design characteristics and the specific waste stream to be processed will significantly
affect the comparison of the benefits to be gained from volume reduction versus the associated
costs and risks from emissions and ash residue.
xv
-------
-------
1. Overview of Radioactive and Mixed Waste Incineration Experience
1.1 RADIOACTIVE AND MIXED WASTE CHARACTERISTICS
Providing a detailed description of the complete spectrum of radioactive and mixed wastes
generated in the United States is beyond the scope of this project. Therefore, this section
provides only an overview of radioactive and mixed wastes. Most, but not all, of the data
presented focus on waste generated at the Los Alamos National Laboratory (LANL) in support
of U.S. Department of Energy (DOE) defense and research related activities, and by facilities
included in surveys conducted by the Conference of Radiation Control Program Directors
(CRCPD) and the University of Maryland.
The emphasis on LANL waste derives from the project objective to assist the State of New
Mexico. It should be noted that the quantities and types of waste generated DOE-wide can not
be inferred from LANL waste information. Further, the emphasis on LANL has no implication
relative to its contribution to the total volume of DOE waste. DOE is currently collecting
information on the volumes of combustible waste generated at each DOE site. A preliminary
summary of combustible mixed waste volumes is shown in Exhibit 1. Finally, it should be noted
that, although not yet fully operational, the Toxic Substances Control Act (TSCA) Incinerator
at Oak Ridge is DOE's principal incineration activity.
For this report, waste is broadly characterized as low-level radioactive waste (LLW), transuranic
(TRU) wasteland mixed waste. This characterization is not intended to represent current
activities, but rather to provide perspective on the different types of chemical and physical
forms, radionuclide distribution, radioactivity levels, and quantities based on past aggregate
practices. The types of waste which are routinely generated do in fact vary greatly depending
on the type of research, production, and cleanup activities that may be typically undertaken at
a given facility. The data reflect past practices in an aggregate form rather than on a yearly
generation rate basis.
1-1
-------
1.1.1 Low-Level Radioactive Waste
Low-level radioactive waste is normally acceptable for disposal in a land disposal site. By
definition, low-level radioactive waste does not include high-level radioactive waste, spent fuel
elements or rods, transuranic waste, and uranium and thorium tailing waste. Low-level waste
may contain a number of mixed fission products, typically about 100 different radionuclides,
depending on the radiological half-life, radioactive decay, and initial amounts present. Waste
may contain long-lived radionuclides, such as strontium-90, technetium-99, iodine-129 and
tritium. Short-lived nuclides such as iodine-131 may also be present.
The typical LLW volume and radionuclide distributions at LANL are shown in Table 1-1. Dry
solids, decontamination debris, and contaminated equipment, in decreasing order, make up
nearly 96 percent of the total waste volume. Over 99 percent of the total activity is contained
in dry solids, decontamination debris, and in unspecified waste forms. Reported radionuclides
include primarily tritium (95.8 percent) and fission products (1.7 percent), with the balance
comprising uranium, thorium, and alpha emitters with concentrations of less than 100
nanoCuries/gram. Equivalent data for other DOE sites can be found in "Integrated Data Base
for 1989: Spent Fuel and Radioactive Waste Inventories, Projections, and Characteristics"
(DOE89).
In 1982 and 1984, the Conference of Radiation Control Program Directors (CRCPD) surveyed
the low-level radioactive waste disposal practices, including incineration, of nearly all radioactive
material licensees in the United States (CRC84). Licensees were asked to report the volume and
activities of waste disposed of and incinerated in those years. Individual survey forms were
obtained and used in the preparation of this report.
1-2
-------
Table 1-1. LANL typical low-level radioactive waste generation and disposal reflecting past
cumulative practices (a)
Physical Form
Contaminated equipment:
Decontamination debris:
Dry solids:
Solidified sludge:
Other forms or not classified:
Radionuclides
Uranium/Thorium:
Fission Products:
Tritium:
Alpha (less than 100 nCi/g):
Percent of Total
Volume Activity
14.0 0.4
22.0 30.3
60.6 50.0
3.1 0.0
0.2 19.3
- 0.02
1.7
- 95.8
- 0.4
(a) Extracted from Tables 4.4, 4.6, and 4.7, DOE/RW-0006, Rev. 5, Nov., 1989 (DOE89).
(b) Only principal items listed, in order of importance.
1-3
-------
The CRCPD survey defined 60 categories of licensees. However, many of these did not
incinerate waste. For this summary, the 60 categories were aggregated into 10, as shown in
Table 1-2. The volumes, nuclides and types of waste reported as incinerated by these licensees
are also shown in Table 1-2. The average volume of waste incinerated was 1,600 cubic feet per
licensee. Most of the volume was reported by nuclear fuel fabricators. Five such facilities
reported incinerating 183,000 cubic feet, with one facility responsible for 130,000 cubic feet.
The activity contained in such waste was principally from uranium radionuclides. Facilities
classified as academic (research and education) incinerated over 21,000 cubic feet of low-level
radioactive waste in 1984. Four hospital categories combined incinerated an estimated 33,000
(adjusted) cubic feet of waste. The categories of private research and development, and
manufacturing each accounted for approximately 11,700 cubic feet of incinerated waste.
A survey conducted in 1979 by the University of Maryland revealed that 45 out of 142 licensed
institutional facilities routinely incinerated radioactive wastes (EGG80). The facilities surveyed
included hospitals (16.9 percent), hospitals combined with medical schools and universities (48.6
percent), medical schools only (7.7 percent), medical schools and universities (16.9 percent),
and universities only (9.9 percent).
In the University of Maryland survey, waste forms routinely incinerated were characterized in
eight categories (see Table 1-3). The survey breakdown indicates that essentially all facilities
incinerate animal or other forms of biological wastes. It is not uncommon for such facilities to
incinerate two or more different waste forms; hence, the cited values need not add up to 100
percent. Scintillation fluids and vials typically make up less than 18 percent of the waste being
incinerated. Aqueous and organic liquid wastes were cited by 13 and 11 percent of the facilities
surveyed, respectively.
1-4
-------
Table 1-2. LLW generators that incinerated waste in 1984(a)
Volume Incinerated(ft3)
Category Average Range
Nuclear Fuel Fabricators 36,500 434-1.3 x 10s
Hospitals/Clinics/ Private Offices 300 1-4,903
Medical Research Hospitals 440 1-3,900
Academic (Research and Education) 449 1-1,198
Medical Laboratories 32 1-150
VA and Federal Hospitals 579 2-5,177
State Hospitals 142 12-579
State & Federal - Non-medical 449 8-1,008
Private R&D 345 6-2,200
Manufacturing 1,342 8-7,800
All 1,594 1-1.3 X 10s
Principal
Nuclides
U-235,
U-238
C-14, H-3, 1-
125
H-3, C-14
H-3, C-14, S-
35, P-32
1-125, H-3
H-3, C-14, S-
35
H-3, C-14
H-3, C-14
C-14, H-3, S-
35
H-3, C-14, I-
125, U-238
—
Waste Types(b)
Trash &. Solids
Trash & Solids,
Liquid Scint.,
Animal
Carcasses
Trash & Solids,
Animal
Carcasses,
Liquid Scint.
Trash & Solids,
Animal
Carcasses,
Liquid Scint.
Liquid Scint.
Trash & Solids,
Animal
Carcasses,
Liquid Scint.
Animal
Carcasses
Liquid Scint.,
Trash & Solids
Animal
Carcasses,
Liquid Scint.,
Trash & Solids
Animal
Carcasses,
Liquid Scint.
(a) Values are as reported and are not adjusted for the survey response rate. Source:
DOE/ID/12377, 1984 (CRC84).
(b) Only principal items listed, in order of importance.
CRCPD Survey,
1-5
-------
Table 1-3. Waste form distribution and incineration reported by institutional facilities(a)
Waste Forms Incinerated
Percent of Respondents That
Incinerated This Form
Free scintillation fluids
Empty scintillation vials
Full scintillation vials
Other organic liquids
Aqueous liquids
Animal carcasses/other biological wastes
Dry solid waste
Other waste-not specified
11.1
4.4
17.8
11.1
13.3
95.6
28.8
17.8
(a) Practices characterizing 45 out of 142 surveyed facilities. Extracted from Appendix C,
EGG-WM-5116, April 1980 (EGG80).
1.1.2 Transuranic Waste ,..-...
The EPA standards (40 CFR Part 191) define transuranic waste (TRU) as containing more than
100 nanoCuries/gram of alpha-emitting transuranic isotopes, with half-lives greater than 20 years
(EPA89). The alpha emitting isotopes of plutonium, curium, americium, and neptunium found
in transuranic waste present a hazard because of their long radiological half-lives and potential
chemical toxicity. Most radionuclides contained in TRU waste are typically present at low
concentrations (DOE89, EPA89). Although a few decay products have energetic gamma, beta
and neutron emissions, their most significant hazard is due to alpha radiation emissions.
In contrast to other radioactive waste, TRU waste includes liquid and solid materials with widely
varying chemical and physical properties. Most TRU waste is classified as "contact-handled"
(CH) TRU waste, i.e., it has a surface dose rate of less than 200 milliRoentgen per hour (mR/h)
or less, and can be handled with just the shielding that is provided by the waste package itself.
A smaller volume (2.5 percent) may be contaminated with sufficient beta, gamma, or neutron
1-6
-------
activity to require remote handling. This waste is categorized as "remote-handled" (RH); i.e.,
it has a surface dose rate of greater than 200 mR/h.
The estimated inventories of retrievably stored TRU waste at LANL are shown in Table 1-4.
The total amount and activity in contact handled waste is greater than that of RH waste by nearly
three orders of magnitude. The bulk of the waste consists of noncombustible materials,
combustibles, and absorbed liquids or sludges. These waste forms are more predominant in CH
waste and are about equally divided between stored and newly generated waste.
The radionuclide compositions of various TRU waste buried or retrievably stored at LANL,
sorted by DOE waste mixes, are given in Table 1-5. The waste mixes represent variations in
waste compositions based on the total amount of the waste volume placed in storage and
generated. The DOE literature does not identify the source of waste according to origin or
process. Four radionuclides make up essentially all of the waste activity. These radionuclides,
in decreasing order, are plutonium-239, americium-241, uranium-235, and uranium-238. Mixed
fission products make up a small fraction of the total activity. The remaining radionuclides
(plutonium-238, plutonium-240, plutonium-241, and other unspecified nuclides) make up less
than a few percent of the total inventory. Again, equivalent data for other DOE sites can be
found in the report, "Integrated Data Base for 1989: Spent Fuel and Radioactive Waste
Inventories, Projections, and Characteristics" (DOE89).
1.1.3 Mixed Wastes
By definition, mixed waste contains radioactivity as well as chemical hazardous constituents.
Such waste is in physical or chemical forms which do not readily allow, the separation of the
radioactive and nonradioactive species. Mixed waste is subject to the Atomic Energy Act (AEA)
and the Resource Conservation and Recovery Act (RCRA) and is primarily governed
1-7
-------
Table 1-4. LANL total inventories of retrievable TRU waste through 1987(a)
Quantity and
Activity
Volume (m3):
TRU Mass (Kg):
Alpha Activity (Ci):
Waste Composition(%>)
Absorbed liquids
or sludge
Combustibles
Contact Handled
7,452
542
187,717
Contact Handled
Stored New
22 10
8 25
Remote Handled
11.1
0.7
63
Remote Handled Buried
Stored New
4
50 50 7
Concrete or cemented
sludges
Soil, gravel, or
asphalt
Filters or glass
media
Glass, metal, or
similar non-
combustibles
36 15
30 48
50 50
44
30
2
13
(a) Extracted from Tables 3.5 and 3.7, DOE/RW-0006, Rev. 5, Nov., 1989 (DOE89).
1-8
-------
Table 1-5. Radionuclide composition and waste mix of buried and retrievably stored TRU
wastes reflecting past practices at LANL(a)
Radionuclide Composition (weight percent)
Sorted By Waste Mix Designation(b)(c)
Contact Handled
Radionuclides 1234 5
U-235:
U-238:
Pu-238: 5 0.5 1.2 0.5
Pu-239: 92 21.5 98.893.0100
Pu-240:
Pu-241:
Am-241: 3 78 6.5
Mixed fission
products:
Others:
Remote Handled
78
47 47
28 28
22.7 22.7
2.1 2.1
0.2 0.2
(d) (e)
Buried
IQ
5
1
91
3.3
0.69
(a) Extracted from Table 3.8, DOE/RW-0006, Rev. 5, Nov., 1989 (DOE89). The
designation of "waste mix" is used by DOE to differentiate between batches of wastes of
varying compositions.
(b) For radionuclides that are either > 1 percent by weight, or > 1 percent by activity
compared to the total.
(c) Mixes represent major variations in waste composition based on the total of the volume in
storage and generated.
(d) Trace amounts by weight-percent, but comprises 85 percent of the activity.
(e) Trace amounts by weight-percent, but comprises 95 percent of the activity.
1-9
-------
by EPA regulations under 40 CFR Parts 260, 262-265, 268, and 270 (EPA87). Section 6001
of RCRA explicitly subjects all Federal facilities and their activities to State and Federal
regulations under RCRA. However, RCRA Section 1006(a) relieves facilities operating under
the authority and control of the AEA from compliance with RCRA for conditions which would
be inconsistent with the requirements of the AEA.
As with the other waste forms described earlier, the presence of organic compounds and metals
in mixed waste will vary significantly from year to year. Accordingly, the following description
is given to illustrate, not to characterize, LANL practices for a specific time period. Table 1-6
indicates that most of the mixed waste at LANL consists of solidified materials, solutions,
combustibles, and metals, representing over 90 percent of the total
waste by weight. Mixed waste constituents also vary over a wide range of concentrations.
Organic compounds, which may include halogenated solvents, polymers, liquid scintillation
cocktails, lathe coolants, degreasers, and oils, vary from a few to several hundred thousand
ppm. Metals are reported at still higher concentrations, up to one million ppm. It should be
noted that the data shown in Table 1-6 represent default mixed waste characteristics for
developing waste acceptance criteria for the Waste Isolation Pilot Plant (DOE90).
1.1.4 Incinerable Wastes
The preceding information characterized in a general way the radioactive and mixed wastes
generated or stored at LANL in support of DOE defense and research related activities. To
provide a more in-depth understanding of the types and quantities of waste forms which will be
incinerated, the following focuses on the types of waste which are known to be targeted for
incineration at LANL.
The characterization is based on several compilations of data gathered by DOE low-level and
mixed waste task groups, including a survey of DOE facilities that currently use incinerators or
plan to install new ones (EGG88, DOE89, HUT90). As noted before, the actual distributions
of waste volumes and properties may change because of DOE's current activities associated
1-10
-------
Table 1-6. Approximate distribution and chemical constituent content of mixed waste forms
(a)
Waste Form(b)
Typical Distribution
Waste Form Chemical Constituent
Quantity (wt-%) Concentration (mg/Kg)(o)
Cemented and
uncemented aqueous:
Cemented and
uncemented organics:
Immobilized process
and laboratory solids:
Combustibles:
Metals:
Spent Filters:
Inorganic solids:
Leaded rubber:
36
10
1
20
25
6
1
1
10 - 700
50,000 - 150,000
10-200
750-2,000
1,000,000
50 - 150
100 - 8,000
600,000
(a) Extracted from Tables B.3.1 and B.3.2, DOE/EIS-0026-FS, Vol. 2, Jan. 1990 (DOE90).
(b) Chemical constituents typically include trichloroethane, carbon tetrachloride, trichloro-
and trifluoethane, methylene chloride, methyl alcohol, xylene, butyl alcohol, acetone,
toluene, PCBs, NaOH, etc. Metals typically consist of cadmium, lead, etc.
(c) Units represent mg of chemical constituents per Kg of waste form.
activities associated with the Environmental Restoration Program. Also, DOE is in the process
of revising its low-level and mixed waste acceptance criteria; a similar revision is being done
for TRU waste (HUT90). Accordingly, the following characterization gives only a snapshot
description of low-level and mixed waste disposal and treatment practices at LANL.
1-11
-------
The current yearly mixed waste generation rates are given in Table 1-7 based on 1989
Department of Energy data for LANL (HUT90). A review of Table 1-7 indicates that 305,000
Ibs/yr, or nearly 50 percent by mass, of the waste is generated in a liquid form. About 35
percent of the total waste quantity is identified as mixed waste. An additional source of waste,
not identified in this table, is contaminated soil; however, no data were provided about its
volume, quantity, and combustibility. LANL estimates that about half of its waste is currently
in a combustible form (EGG88).
Under a new low-level and mixed-waste management program, LANL plans to establish onsite
treatment capabilities, increase treatment capacities to meet newly anticipated requirements,
separate TRU from non-TRU waste treatment processes, and develop more comprehensive waste
acceptance criteria (waste acceptance criteria have been established by DOE to regulate its
overall waste management activities and programs) to handle new or additional LANL waste
streams (DOE89a, EGG88). Some of these wastes are targeted for incineration.
The waste forms and volumes or quantities for LANL are given in Table 1-8. The total low-level
waste volume inventory is 4,373 m3, which consists of 3,052 and 1,321 m3 of alpha and
beta/gamma wastes, respectively. Mixed waste is comprised of 175 m3 of solid materials and
3,700 gallons of liquids. The primary radionuclides are reported to be isotopes of plutonium,
americium, curium, and tritium and carbon-14. Some fission products, such as strontium, are
also present in unspecified quantities. The reported concentrations are cited relative to
established limits as defined by the DOE waste acceptance criteria. For example, the limit for
solid wastes is expressed in terms of exposure rate; i.e., less than 10 mr/h. Alpha emitters are
expressed in terms of TRU concentration; i.e., less than 100 nanoCuries/gram. The maximum
radioactive concentrations for liquids are given as less than 0.1 microCurie/liter as total activity,
which is interpreted to apply only to beta/gamma emitter radionuclides.
1-12
-------
Table 1-7. Estimated yearly mixed waste volume and mass generation rate by physical forms
forLANL(a)
Waste
SOLID:
LLW DAW
LLW
Mixed LLW
Mixed LLW
LIQUID:
Mixed
LLW oils
Grease
Forms
Not RCRA
Biological
Solids
Uranium
Total:
Stint, fluid
Not RCRA
Not RCRA
total:
Volume
(FtVyr)
15,000
600
29,000
350
44,950
500
4,600
700
5,800
Quantity
(Lbs/yr)
112,000
11,000
220,000
18,000
361,000
5,000
260,000
40,000
305,000
(a) Extracted from Table I: Los Alamos Combustible Radioactive and Mixed Waste
Characterization (HUT90).
LLW = Low-Level Waste
DAW = Dry Active Waste
1-13
-------
Table 1-8. Summary characterization of waste volumes, radiological properties, and
inventory at LANL(a)
Characteristics
Volume or
Quantity (b)
Radiological
Properties(c)
Total LLW
volume (m3):
Combustible
fraction of LLW:
Low-level Combustible
9,436
0.46
total volume (m3):
TRU:
Beta/gamma:
Mixed waste:
Solids (m3):
Liquids (gal.):
Total activity:
Total TRU:
4,373
3,052
1,321
175
3,700
—
<0.1 uCi/g
< 10 mr/h.
<0.1 uCi/g
<0.1uCi/L
<0.1 uCi/g
(a) Extracted form Table 2-1, EGG-LLW-8269, October 1988 (EGG88).
(b) All values are rounded off.
(c) Primary radionuclides are reported to be Pu, Am, Cm, H-3,
C-14, and fission products, such as Sr, and Ce.
1-14
-------
1.2 COMBUSTION PROCESS AND RADIONUCLIDE EMISSIONS
1.2.1 Radionuclide Airborne Emissions
Waste may be introduced into an incinerator in a bulk material (e.g., as boxes, bags, or drums),
shredded, in a sludge form (e.g., slurry), or injected as liquid (EGG88). The feed rate is
governed by the combustible nature of the material and by the introduction of an additional
source of fuel. Sometimes the waste, if in a liquid form, may be introduced as a mixture of fuel
and waste. The waste/fuel ratio is determined by the combustion properties of the waste and
incinerator capacity. The considerations noted above apply generally to all waste forms (mixed
and low-level wastes) introduced into incinerators. As combustion occurs, oxygen is consumed
and the combustion gases are entrained in the afterburner. The proper combustion conditions
are maintained by controlling the amount of air, waste feed rate, and temperature. Special
attention is given to the residence time in order to ensure that complete oxidation occurs and that
the air/fuel mixing is also adequate for total combustion.
Eventually, combustion gases, suspended particulates, fumes, and products of incomplete
combustion are entrained in exhaust scrubbers and filtration devices before being released from
the stack. The chemical and radioactive constituents of the off-gas can vary significantly from
those of the input waste. The combustion process does not destroy trace metals or radioactivity,
nor does it change the rate of radioactive decay, but rather it changes only the chemical and
physical forms of the radionuclides.
The most often encountered radionuclides, tritium, carbon, and iodine, are generally released
with little or no retention in the incinerator. Such radionuclides form gases which retain their
radioactivity. Semivolatile elements, for example lead, polonium, sulfur, cesium, mercury, and
phosphorus, may, under oxidizing and reducing conditions, form volatile fumes even at moderate
combustion temperatures. At elevated temperatures, hydrochloric acid (HC1) produced from the
burning of polyvinyl chloride, metals, and metal oxides present in the waste may become
volatilized to various degrees (TRI89, RIN_, BAR_). The temperatures at which elements are
1-15
-------
classified as volatile or semivolatile are dependent on the chemical form of the element and its
residence time in the combustion chamber. The amounts of trace metal or metal oxides
volatilized depend on the partial pressures of O2, HC1, and H2O, the waste feed rate, the particle
surface area, and off-gas flow rate. Longer residence times, normally required for the
destruction of organic compounds, result in greater formation of metal oxide fumes (TRI89).
These fumes, generally less than 0.1 um in size, are usually exhausted out of the stack because
of their small size. Radionuclides that volatilize at higher temperatures will also become
entrained in their vapor form and coalesce as particulates at cooler temperatures. Such
radionuclides will condense onto suspended particles present in the exhaust stream forming
radioactive particulates which may have higher specific activities than the waste itself.
This process, known as enrichment, depends largely on the individual radionuclide, its behavior
at oxidizing temperatures and particle size distribution in the exhaust stream (UNS82, TRI89,
GAL__). This process reflects the depletion of certain elements in the settling ash, the higher
surface to volume ratio of the fumes, and the surface reactivity of the fumes. For example, coal
combustion in a coal-fired boiler has revealed varying enrichment factors, ranging from 1 to 2
for radium, uranium, or thorium. Higher enrichment factors were observed for lead-210 and
polonium-210, typically ranging from 1 to 11 (UNS82).
Volatilized radionuclides may be readily removed from the off-gas prior to discharge into the
atmosphere by simply cooling the gases. Cooling causes the vapor to condense out of the
airstream and onto surfaces or into components. This deposition process is beneficial since it
reduces stack emissions, but is also detrimental since it may result in radionuclide deposition in
undesirable parts of the off-gas treatment system. Preferably, the deposition should occur in
scrubbers, filters, or components designed for the collection and removal of fly-ash or fume
residues. For TRU waste, the accumulation of fissile radionuclides at specific locations may
present a criticality problem (the condition in which a nuclear reaction is just self-sustaining)
(CARJ.. However, given the relatively low concentration of TRU waste, criticality safety should
not normally be a concern (IAE89).
1-16
-------
Off-gas treatment typically involves passing the hot flue gases into a series of components to
remove suspended particulates, gases, and radionuclides. Such systems typically include heat-
exchangers, filters and separators, high efficiency particulate air (HEPA) filters, and adsorbers.
Other forms of off-gas cooling include quenching by water injection and dilution by introducing
air at ambient temperature. Particulate emissions, depending on particle sizes and exhaust
velocity, are trapped in heat-exchangers, filters or electrostatic separators.
Typically, large particles, which are too heavy to be entrained by the exhaust stream, settle onto
surfaces or are trapped by the filters and electrostatic separators. As noted earlier, as the
temperature cools, vapors condense out of the airstream and deposit or impinge onto surfaces.
Smaller particles are entrained in the exhaust stream because of their smaller size and mass.
HEP A filters are designed to remove small particles, typically with a collection efficiency of
99.97 percent for 0.3-um diameter particles (ERD76). HEPA filters may be installed in tandem
with two or more units in series and are usually placed before the carbon adsorbers. Pre-filters
are also placed before the HEPA filters to prolong their useful lives.
Vapors and gases that have not condensed out of the airstream may be collected by using
adsorbers; e.g., carbon filters, which may be treated with potassium iodide (KI) or
triethylenediamine (TEDA) for improved collection efficiency, typically ranging from 95 to 99
percent (ERD76). Depending on the application, a second set of HEPA filters may be installed
beyond the carbon filters to trap what is known as "carbon fines," which may be released from
carbon granules. Carbon fines may contain elevated radionuclide concentrations. Sometimes
wet scrubbers are also installed to trap acid or organic vapors (HC1, HF, NH3, SOX, and NO*)
from the exhaust stream. If wet scrubbers are installed, they are usually followed by demisters
and driers, which remove water vapors from the exhaust stream. Excess water vapors tend to
saturate HEPA filters and carbon adsorbers, rendering them totally ineffective.
These off-gas components, when installed as one engineered system, can provide very high
collection efficiencies. The system reliability depends on how the system is operated and
maintained. The overall collection efficiency is also nuclide-dependent; for example, it is lower
1-17
-------
for cesium than for plutonium. Operating experience indicates that the overall collection
efficiencies of systems range widely. In a survey of operating facilities, an International Atomic
Energy Agency (IAEA) report cites efficiencies, expressed in terms of overall decontamination
factor (DP), ranging from as low as 10 to as high as 107 (IAE89). (For treatment of hazardous
materials, incinerators are rated in terms of destruction and removal efficiencies, or DREs. The
DRE is an inappropriate concept for radioactive materials, since radiation is not destroyed by
the incineration process.) The DF is expressed as the ratio of the amount of radioactivity
introduced in the incinerator to the amount that is observed on the exit side of the final off-gas
treatment system component (e.g., HEPA filter or carbon adsorber). A cluster of DFs were
noted ranging from 1O5 to 106. A few facilities reported overall DFs ranging from about 10 to
104. It should be noted that the cited DFs represent different types of incinerator systems,
incinerators with different capacities, and varying waste forms and radionuclide concentrations.
Finally, not all systems were similarly equipped with off-gas treatment systems. Some facilities
were equipped with more elaborate off-gas treatment equipment than others.
Actual airborne radionuclide emissions are also known to vary for the reasons given above. In
addition, many incinerators process waste with radiological and physical properties that vary as
a function of time. Accordingly, it is difficult to characterize emissions in generic terms. A
general perspective on the type and extent of airborne emissions can, however, be obtained from
operating facilities. Unfortunately, little information exists that directly compares the
radiological properties of the waste introduced in the incinerator with actual airborne emissions.
Typically, data only summarize airborne emissions on a yearly basis, with no correlation with
waste throughput.
1-18
-------
1.2.2 Radiological Properties of Ashes and Residues
The volume reduction of low-level radioactive waste in an incinerator results in higher
concentrations of radioactivity and higher radiation levels in the end product, ash, when
compared to the feed material. System design (including building layout where appropriate)
should minimize personnel interaction with equipment and vessels that contain ash. Shielding
of ash collection bins and other ash handling equipment may also be needed.
The bulk of the feed material is consumed during the combustion process while a change in the
chemical form of the waste occurs. As the material is oxidized, certain compounds are formed,
typically sulphates, chlorides, fluorites, nitrates, phosphates, and metal oxides, depending upon
the waste. In a rotary Mm, for example, as the combustion process occurs, the ashes are
collected at the bottom of the kiln and the rotation of the kiln forces the ash to collect in
collection bins. Some of the ash, however, is entrained with the off-gas and settles or collects
in various parts of the off-gas treatment system. The deposition of ash in various parts of the
system is dependent upon off-gas velocity, particle size and density, combustion process,
residence time, and the type of treatment system components; e.g., filters, electrostatic
separators, scrubbers, HEPA filters, carbon adsorbers.
The distribution of ash in various incinerator components is shown in Table 1-9. The bulk (91
to 94 percent) of the ash is retained in collection devices at the point of combustion. Smaller
amounts are retained in other sections of the incinerator system, such as the post-combustion
chamber (2-4 percent), filter bags (1.5-5.2 percent), and cyclone (1-3 percent). Minimal
amounts, less than 2 percent, are retained on HEPA filters, cooling coils, and diffusers, and
Other unspecified locations.
1-19
-------
Table 1-9. Typical distribution of ash in incinerator components(a)
Components
Range of
Distribution (percent)
Ash collection bin
Post-combustion chamber
Bag Filters
Cyclone
Diffuser
Heat Exchangers
HEPA filters
Other miscel.
locations
91-94
2-4
1.5 - 5.2
1-3
~ 0.5
~ 0.4
~ 0.6
0.04-2
(a) Extracted from IAEA Technical Report Series No. 302, Appendix A, 1989 (IAE89).
The deposition of ash in various parts of the incinerator, other than in ash bins, is a potential
problem since the ash must be periodically removed. Because ash contains radioactivity, now
present at a higher specific activity, ash removal and handling must be performed under
controlled conditions. However, for some volatile radionuclides (e.g., tritium and iodine-125),
the ash may contain only trace amounts or no radioactivity at all. Usually ash handling is
performed remotely, via a ram or conveyor, and the operator is separated from the ash by a
physical barrier. The ash is removed following an appropriate cool down period. The process
is also performed with proper ventilation to keep the ash from being dispersed in the immediate
area or from being resuspended. The ash may be discharged into a glovebox and chute
connected to a drum. Ash may be dumped directly into its disposal containers or processed;
e.g., via cement, bitumen, or thermosetting resin solidification followed by packaging.
The amount of ash produced depends on the physical and chemical properties of the waste. For
the type of waste to be processed by the LANL incinerator, volume-reduction ratios of about 10
to 25 are anticipated (NRC83). The ashes typically consist of fine (80-90 percent) and oaas
(clinkers) material (10-20 percent). The density of fines and clinkers varies from about 0.9 to
1-20
-------
3.0 g/cm3. The chemical composition of ash fines varies as well, but typically consists of oxides
and carbon compounds. Oxides include SiO2, A12O3, CaO, TiO2 and lesser amounts of FeA,
K20, MgO, Na20, and P2O5 (NRC83). Oxides may make up about half of the total ash, by
weight. The balance may be comprised of carbon compounds, chlorine, other metal oxides, and
refractory material.
Ash particle sizes vary from relatively large to small diameters. About three -quarters of the
ash particle sizes cluster around a 500- to 10-um particle diameter. Only a few particles are
above 500 or below 10 urn in size. Ashes from solid and liquid wastes show only a small
difference in particle size. The following provides a breakdown of particle sizes for two types
of waste streams (RFP82):
Particle size
Range (um)
> 1000
1000-500
500-100
100-20
20-10
10-5
5-0.5
< 0.5
Weight % Distribution
Solids Liquids
2
6
20
32
25
10
4
2
3
10
55
22
5
2
Clinkers are typically several inches in length or diameter and at times may be found fused
together in large chunks. They are formed during the combustion of rubber, plastic, wood, or
resins, etc. Clinkers may appear very sooty, and are also usually porous, about 30 to 50 percent
porosity. Again, these properties may vary depending on the nature of the waste initially
introduced into the incinerator.
The radiological properties of ash depend on the initial amounts of radioactivity present. As
discussed, volatile radionuclides will not remain in ash residues. Because of the volume
reduction normally encountered, ash will have higher specific activities. Radionuclide
1-21
-------
concentrations may range from nondetectable levels to very high concentrations which require
special handling procedures. Other than the Toxicity Characteristic Leaching Procedure (TCLP)
test to simulate leaching of eight metals (including lead, cadmium, mercury, chromium, and
barium) four pesticides, two herbicides, and 25 organic compounds (EPA90), ash is generally
believed to be free of other hazardous material properties. The distribution of radioactivity in
ashes is shown in Table 1-10 for a number of radionuclides.
Table 1-10. Typical radionuclide distribution in incinerator ash(a)
Radionuclide
Distribution (percent)
Pu
Cs-137
Cs-134
Co-60
Ag-llOm
Ru-106
Zn-65
Sb-125
Zr-95
Sr-85
Se-75
Sc-46 (microspheres)
1-125
H-3
77-82
77
8
6
3
2
1.5
0.8
0.3
86
0.3
79-98
< 1
< 1
(a) Extracted from IAEA Technical Report Series No. 302, Appendix A, 1989
(IAE89), HPS Vol. 44, No. 6 (LAN83), Waste Management-85 (WM85),
and DOE/LLW-12T, Nov. 82 (EGG82).
There is a problem inherent in characterizing radionuclide distributions and concentrations in
ashes. The presence of radionuclides in ash is highly dependent on the sequence of the burn and
the material that is initially radioactive. The ash will settle according to physical properties
(e.g., particle size and density) (EGG82, LAN83, WM85). Accordingly, the
1-22
-------
radioactivity in the ash will also be layered during the combustion process until the ash is
physically removed.
The ash removal system will disturb this distribution by stirring and mixing the ash, in effect
diluting the radioactivity over a larger ash volume. Experience has shown that it is not
uncommon to have discrepancies on the order of 20 to 50 percent when attempting to account
for the distribution of radioactivity (EGG82, LAN83, WM85). As noted earlier, this aspect is
further complicated by ash that settles or deposits in other parts of the system and by the smaller
amount released through the exhaust stack.
Among the principal factors to be considered in evaluating the environmental impacts of
radioactive ash disposal are worker radiation exposures and exposures to the public due to
transportation to the disposal site. Additionally, the impact of disposal of the original feed
material should be considered by comparison. In some instances, the presence of RCRA-
regulated materials in the feed material would prohibit the land disposal of the waste material,
resulting in possibly prolonged storage.
NRC regulations governing acceptable forms for land disposal of low-level waste are contained
in 10 CFR 61. Solidification of the radioactive ash is required prior to shipment for disposal.
Department of Transportation regulations which govern the packaging, preparation for shipment,
and transportation of radioactive waste are contained in 49 CFR 173, Subpart I. Additional State
regulations may apply, depending on the disposal site to be used.
Currently there are only three approved commercial disposal sites in the United States for low-
level radioactive waste: Barnwell, South Carolina; Beatty, Nevada; and Richland, Washington.
Others are expected to be opened in the early 1990s to meet the requirements of the Low-Level
Waste Policy Act Amendments of 1985. Disposal of government waste may be permitted at
selected federally owned sites.
1-23
-------
1.3
INCINERATOR POPULATION
Although the historical operating experience base is still quite limited for radioactive and mixed
waste incineration, the shrinking availability of publicly acceptable means of waste disposal and
subsequent need to minimize waste quantities are generating increased efforts to use incineration
to reduce the volume and hazardous chemical content of waste material. This section discusses
some of the radioactive/mixed waste incinerators now in use or under consideration.
Operable incinerators are located at four U.S. Department of Energy (DOE) facilities. These
are the controlled air incinerator at the Los Alamos National Laboratory (LANL), the Oak Ridge
Toxic Substances Control Act (TSCA) incinerator, the Rocky Flats Plant (RFP) fluidized bed
incinerator, and the Idaho National Engineering Laboratory (INEL) Waste Experimental
Reduction Facility (WERF). Schematics of these incinerators are provided in Figures 1-1
through 1-4. Additionally, a new controlled air incinerator is planned for LANL, and a rotary
kiln incinerator (the Consolidated Incineration Facility, or GIF) is planned for the Savannah
River Site. The Savannah River Site Beta-Gamma incinerator, shown in Figure 1-5, was
shutdown several years ago for equipment modifications. When the GIF was approved,
modification of the Beta-Gamma incinerator was canceled, and there are no plans to restart this
unit. DOE has discontinued work at the INEL Process Experimental Pilot Plant (PREPP)
incinerator shown in Figure 1-6, while evaluating its future role in the DOE Waste Management
Program.
A low-level radioactive waste incinerator owned and operated by the Scientific Ecology Group,
Inc. (SEG) in Oak Ridge, Tennessee, began commercial operation in 1989. The SEG
incinerator, shown in Figure 1-7, is an automatically controlled partial-pyrolysis unit, based on
the Swedish Studsvik incinerator, which has been in service since 1976.
1-24
-------
©
1. Multiple Energy Gamma Assay
System (MEGAS)
2. Micro-dose x-ray waste package
scanner
3. Waste receiving glovebox with air-
lock entry
4. Side ram feeder
5. Main ram feeder
6. Combustion fuel/air supply glovebox
7. Incinerator ignition (primary) chamber
8. Inter chamber
9. Incinerator combustion (secondary)
chamber
10. Incinerator chamber access
gloveboxes
11. Quench column
12. High-energy venturi scrubber
13. Packed column scrubber
14. Off-gas demister
15. Off-gas superheater
16. HEPA filters (first and second stages)
17. Activated carbon adsorber
18. HEPA filter (third stage)
19. Off-gas monitoring (CO, COj, H2O)
station
20. Continuous stack sample system
21. Continuous stack sample system
22. Facility and process vent stack
23. Scrub-water primary coolant heat
exchanger
24. Isolated secondary coolant loop heat
exchanger
25. Scrub-water hydrocyclone particulate
separator
26. Scrub-water recirculating sump tank
27. Scrub-water blowdown filters
28. Facility liquid sump tank and transfer
system
29. Gravity ash-removal hopper
30. Ash-removal valves
.31. Ash-removal drum system
32. Process instrumentation and control
panels
Figure 1-1. The Los Alamos Controlled Air Incinerator
1-25
-------
INCINERATOR
OFF-GAS HANDLING
SOUDS SHREDDER
SOLID WASTES T FINELY DIVIDED
TOOESHREDOED-i SOLID WASTES
DNIZMG
WET SCRUBBER
PACKED
COLUMN
SCRUBBER
VENTURI /
SCRUBBER
Figure 1-2. The Oak Ridge Toxic Substances Control Act (TSCA) Incinerator
1-26
-------
Figure 1-3. The Rocky Flats Fluidized Bed Incinerator
1-27
-------
Incinerator
room*"
Dilution
air blower
x.r«r
•lion Sytlem
Radiation
WetoM
D
Drum
Drum
Figure 1-4. The INEL Waste Experimental Reduction Facility
1-28
-------
SECONDARY
INTERNAL
RAM
SPRAY
QUENCH
BAG
HOUSE
10 BLOWERS
SOLVENT
FEED
TANK
5S-GAL
DflUMS
Figure 1-5. The Savannah River Site Beta-Gamma Incinerator
1-29
-------
Stack]
Quencher
Venturi
scrubber
v-_
^
0
c
L
Off-gas flow
Entrapment
eliminator
Induced
dranfan'
Mist eliminator
Reheater HE PA
filters
Carbon monoxide monitor
O2 monitor
Receiving
and
shipping
Rotary kiln
Surge
recycle tank
Secondary
combustion
chamber
HO
Residue Trommel
cooler separator
Inspection
and
shipping
Fine
ash
storage
iCement
Figure 1-6. The INEL PREPP Incinerator
1-30
-------
sixoe
Figure 1-7. The Scientific Ecology Group (SEG) Incinerator
1-31
-------
Advanced Nuclear Fuels, in Richland, Washington, operates a dual-chamber controlled-air
incinerator for processing solid and liquid wastes contaminated with uranium. The incinerator
has operated since October 1988. The wastes incinerated originate during the manufacture and
recovery of nuclear fuel materials.
A commercial unit for thermal destruction of mixed waste was permitted in 1990, and is
expected to begin operation in early 1991. This unit, owned and operated by Diversified
Scientific Services, Inc. (DSSI), in Kingston, Tennessee, is designed to use mixed waste, in fluid
form only, as beneficial fuels in a boiler system. DSSI notes that most of the waste will come
from hospitals and universities where various short-lived radionuclides are used,
and that most of the radioactivity will have decayed away before the waste is processed and
received by DSSI. The boiler system is designed for complete thermal destruction of the fuels
and recovery and reuse of the energy produced.
Two electric utility companies investigated incineration for volume reduction of waste produced
at their nuclear generating stations. Duke Power Company installed a fluidized bed incinerator
at its Oconee Nuclear Station in South Carolina. Changes in station operating procedures made
subsequent to the installation of the incinerator changed the potential incinerator feed material
from that originally contemplated. The consequent need for design modifications, and associated
delays, resulted in a decision to defer final
completion and operation of the incinerator for an undetermined period. The incinerator is being
maintained in a layup condition pending a future decision to reactivate. Duke Power now uses
the SEG incinerator described above for its incineration needs (DTJK85, DUK90).
Commonwealth Edison Company installed fluidized bed incinerators similar to the Duke Power
unit at its Byron and Braidwood nuclear stations. These incinerators are also currently in layup.
Table 1-11 summarizes the location, type, status, and waste processed for each of the
incinerators described above.
1-32
-------
Table 1-11. Status of selected U. S. radioactive and mixed waste incinerators
Operator/
Location
DOE/
Rocky Flats
DOE/
SRS Beta-Gamna
DOE/
SRS CIF
DOE/
1 AUI f*A T
LANL CAI
DOE/
LANL LLU/HW
DOE/
INEL UERF
DOE/
INEL PREPP
DOE/
TSCA
Oak Ridge, TN
BNL/HWHF
Brookhaven, NY
Commercial
SEG/
Oak Ridge, TN
DSSI/
Kingston, TN
ANF/
Richland, WA
Type of
Incinerator
Fluidized Bed
Stationary Hearth
Rotary Kiln
Controlled Air
Controlled Air
Controlled Air
Rotary Kiln
Rotary Kiln
Stationary Hearth
Controlled Air
Boiler
Controlled Air
Status
Shutdown -
to be upgraded for
RCRA permitting
Shutdown - Restart
not planned
RCRA Part B permit
submitted 1988. Planned
operation in 1993.
RCRA, TSCA permitted.
shutdown pending EIS.
Planned restart in 1991.
Planned operation in 1997.
Operating under interim
status. RCRA Part B permit
submitted.
Planned operation under
evaluation
Testing, tentative
operation 1991
Operating. Not RCRA permitted
Operating
Planned operation 1991
Operating
Waste
Stream
3,4,8 (no PCBs)
10
1. 2
3, 4, 9
1,2,3,4,5,
6,7,8,9,10
(liquids only)
1. 2, 3, 4
1, 2, 3, 4
5, 6
1, 2, 3, 4, 10
11
1
3
1?
Design
Capacity
(kg/h)
93
182
919
57
181
181
1043
34
727
2 gal/m
Duke Power/
Oconee Nuclear Station
Commonwealth Edison/
Byron and Braidwood
Nuclear Stations
Waste Stream Codes
TRU = Transuranic Waste
LLW = Low-Level Waste
HW = Mixed Waste
Code
Waste
Fluidized Bed
Fluidized Bed
1
2
3
4
5
6
LLW Liquids
LLW Solids
LLW/HW Liquids
LLW/MW Solids
TRU Liquids
TRU Solids
7
8
9
10
11
Lay-up
Lay-up
1, 2
1. 2
Code Waste
TRU/HW Liquids
TRU/MU Solids
Non-Radioactive Hazardous Wastes
Wastes can contain PCBs, except as noted
Very low-IeveI radioactive nuclear
medicine wastes and autoclaved medical wastes
12 Liquid and solid wastes contaminated with U
1-33
-------
A number of smaller scale incinerators are used by medical facilities and other institutions to
process radioactive waste. Using data from the CRCPD survey and assumptions about
nonrespondents, it is estimated that nearly 200 licensees incinerated about 300,000 cubic feet of
low-level radioactive waste in 1984.
International incineration experience was briefly reviewed during this project. A detailed review
of international experience is beyond the scope of this project. Table 1-12 lists location, type,
design, capacity, and waste stream content for operational large scale foreign incinerators. A
survey of the operating history of several European facilities indicates that releases and offsite
exposures are well within established limits (IAE89). Typically, reported airborne releases
range from nondetectable levels to nearly one percent of the imposed limits. Most of the
problems associated with incinerator operations have, however, been experienced with
operational reliability and maintenance (IAE89). Such problems typically include: frequent
replacement of off-gas treatment system filters, corrosion of components, plugging of heat-
exchangers, incomplete incineration, accumulation of residual ashes in systems and components
not designed for ash removal, personnel exposure, contamination control, potential fires in filter
systems, and humidity control and HEPA filter clogging. Such problems have also resulted in
higher operating costs.
One incinerator research project, being conducted under the Superfund Innovative Technology
Evaluation (SITE) Program, has potential application to radioactive and mixed waste treatment
(ESC89). This project, the Plasma Centrifugal Reactor, utilizes high temperatures (exceeding
2800°F) generated by a 600-Kw plasma arc torch to volatilize organic components and
encapsulate heavy metal components in a glassy slag. The volatile metals are captured within
an offgas treatment system. Liquid and solid organic compounds can be treated by this
technology, and it is most appropriate for soils and sludges contaminated with metals and
difficult to destroy organic compounds.
1-34
-------
Table 1-12. International operational large-scale incinerators
Country
Austria
Belgium
Canada
France
Germany
Germany
Japan
Sweden
UK
Italy
Location
Research Centre
(Seibersdorf)
Research Centre
(Mol)
Bruce
Chalk River
Reprocessign plant
(Marcoule)
Research Centres
(Fontenay-aux-
Roxes)
-------
Phase HI testing, originally scheduled for late 1990, was designed to determine the applicability,
operability, and reliability of the system when processing DOE waste. During the tests, waste
materials were to simulate Idaho National Engineering Laboratory (INEL) radioactive and mixed
wastes. These tests were, however, delayed because of inappropriate funding (RET90). In the
interim, RETECH is planning a full scale demonstration at a chemical plant located in
Switzerland. The demonstration tests will be followed by commercial operation at this Swiss
company. The plasma centrifugal reactor will be designed to accommodate 55 gallon drums into
the reactor chamber. Operational test results are expected to become available in early 1991
(RET90).
1.4 OPERATIONAL INCINERATOR EMISSIONS
1.4.1 DOE Incinerators
The following presents information characterizing radionuclide emissions for a few DOE and
two commercial facility incinerators. For DOE incinerators, the information is based on DOE
data prepared in response to NESHAPS reporting requirements under 40 CFR 61.94. The DOE
compiles, on a yearly basis, such data in the Effluent Information System - EPA Release Point
Analysis Report, a computerized database. For the commercial facilities, the information is
extracted from technical correspondence.
The DOE reports provide aggregate data on airborne effluent releases by radionuclides and
emission sources (e.g., buildings, areas, or stacks). In some instances, the release points include
more than one emission source for a given stack or building. The DOE reports do not,
however, present any information characterizing each incinerator emission source contributing
to total releases. Furthermore, these reports do not typically provide any information describing
the activities or waste streams which contribute to overall emissions. Any information
characterizing waste forms and waste volumes was obtained, whenever available, separately from
each DOE facility.
1-36
-------
The tabulations which follow also provide estimates of yearly average airborne concentrations
released from the point of discharge into the atmosphere, but not at off site locations. Offsite
concentrations vary depending upon atmospheric dispersion at specific downwind distances and
receptor locations. Accordingly, offsite airborne concentrations would be still lower than those
shown in the enclosed tables.
Finally, it should be recognized that the information presented below characterizes activities and
emissions which may have since been discontinued or represents waste forms or streams which
are no longer generated. Similarly, some incinerators may have since been modified and
retrofitted with newer or better off-gas treatment technology, or totally taken out of service.
Accordingly, the information which follows provides only a snap-shot characterization of past
waste processing activities and associated airborne radionuclide emissions.
1.4.1.1 Rocky Flats Fluidized-Bed Incinerator. The DOE Rocky Flats facility operates a
fluidized bed incinerator (FBI) designed to recover plutonium from bulk waste. The incinerator
is located in Building 776 and its off-gas treatment exhaust is released into a common system,
Building 776-202 plenum.
The off-gas treatment system is comprised of several components. These components include:
a set of sintered metal filters; a process gas heatexchanger; and a four-stage HEPA filter.
Exhaust emissions are monitored by pulling a continuous sample through a paniculate filter and
an air monitoring and sampling station.
The FBI has never been used in a continuous operating mode. It has only been used for
intermittent tests conducted over a two-year period (LUK90). Three tests were performed to
evaluate the FBI while using radioactive waste. Two tests were conducted in 1979 and another
one was done in 1980. The data associated with these tests are very limited in details, other
than indicating that Pu was the suspected radioactive contaminant in the waste. No specific
radioisotopes were identified (e.g., as Pu-239, Pu-240, Pu-241, etc.). Radionuclide
1-37
-------
concentrations were reported to be at very low concentrations, at less than 10 nCi/g. Some of
the relevant parameters characterizing these runs are shown below:
Test
Run No.
3
4
5
Ending
Date
6/79
8/79
8/80
Waste
Weight(lbs)
1,411
7,011
5,132
Waste Weight
Reduction
4.0:1
• —
4.0:1
Waste Volume
Reduction
—
—
23:1
Extracted from DOE/RFP submittal dated 10/29/90 (LUK90)
Airborne radionuclide emissions for three years, 1986 to 1988, for all releases associated with
the Bldg 776-202 plenum are listed in Table 1-13. The data, however, do not indicate how
much of the radioactivity released is due to other building activities or processes. This is
because the FBI exhaust is fed into a larger system which services Bldg 776. Emissions are
sampled beyond the point of confluence of the two exhaust systems. This feature makes it
difficult to resolve emissions originating only from the FBI.
A review of Table 1-13 indicates that five radionuclides comprise a major fraction (23 to 55
percent for any single year) of the reported emissions. These nuclides are Pu-239, Pu-240, U-
233, U-234, and U-238. Table 1-14 presents yearly average stack concentrations based on the
previously cited yearly releases and given total air volume discharges. The resulting emissions
represent stack radionuclide concentrations and not offsite airborne radioactivity. Stack
concentrations have decreased over the three reported years, except for Pu-239/Pu-240 and U-
238 which have remained relatively stable.
1-38
-------
Table 1-13. Rocky Flats fluidized-bed incinerator emissions00
Radionuclides
1986
Yearly Releases - Ci/yr00
1987
1988
Am-241
Pu-238
Pu-239
Pu-239-240
U-233-234
U-238
5.1E-09
1.2E-09
O.OE-OO
1.9E-08
2.7E-09
1.5E-08
5.7E-09
4.3E-1O
2.1E-08
O.OE-OO
1.4E-08
1.3E-08
2.4E-09
2.2E-1O
O.OE-OO
1.7E-08
5.5E-1O
1.1E-08
(a) Extracted from the U.S. Department of Energy, Effluent Information System - EPA
Effluent Analysis Report For Calendar Years 1986 to 1988, run date 9/18/89.
(b) All values are rounded off and entered as exponential notation; i.e., 5.1E-09 means
S.lxlO-9.
Table 1-14. Rocky Flats fluidized-bed incinerator stack
radionuclide concentrations00
Radionuclides
Average Yearly Concentrations
1986 1987
1988
Am-241
Pu-238
Pu-239
Pu-239-240
U-233-234
U-238
6.7E-17
1.6E-17
O.OE-OO
2.5E-16
3.6E-17
1.9E-16
6.4E-17
4.8E-18
2.4E-16
O.OE-OO
1.6E-16
1.4E-16
4.1E-17
3.7E-18
O.OE-OO
2.9E-16
9.4E-18
1.9E-16
(a) Derived from the U.S. Department of Energy, Effluent Information System - computer run
AFGHE776008A, 8/9/90.
(b) Values shown represent stack concentrations and not offsite airborne activity. Total air
volume discharged through stack is 7.6E+7, 8.9E+7, and 5.8E+7 m3 for 1986, 1987, and
1988, respectively. All values are rounded off and entered as exponential notation; i.e.,
6.7E-17 means 6.7xlO-17
1-39
-------
1.4.1.2 Los Alamos Controlled Air Incinerator. The Los Alamos Controlled Air Incinerator
(CAT) was designed and built to process waste containing transuranics and mixed-fission
products. The incinerator is in Building 37, which is located in Technical Area 50.
Incinerator off-gases are exhausted in a common stack, which also services other areas of
Building 37. This feature makes it difficult to resolve emissions originating only from the CAI.
The CAI off-gas treatment system is comprised of several components. These components
include: a water-spray quench column; a venturi scrubber; a packed column absorber; a
superheater; a set of primary HEPA filters; an activated carbon-bed; and a final set of HEPA
filters.
The stack monitoring system pulls samples near the stack's exit point. Air samples are
continuously taken whether the CAI is operating or not. The samples are drawn, under pseudo-
kinetic conditions (i.e., using a fixed rather than variable sampling flow rate), through a
particulate filter. The filter is changed and analyzed weekly. Radiological analyses are
performed using laboratory procedures. Los Alamos is currently considering the installation of
an on-line alpha/beta monitoring system distributed by EG&G/Ortec. This monitoring system,
of European design, can differentiate between naturally occurring radioactivity (i.e., radon and
thoron decay products) and alpha emitters of interest (e.g., Pu-239, Am-241, etc.).
Four-year summaries of airborne emissions are shown in Tables 1-15 and 1-16. Table 1-15
presents stack release data for 1985 to 1988. Plutonium releases make up a small fraction (a
few percent) of total releases. Mixed-fission products comprise about 98 percent of the total
emissions being reported by the LANL. Yearly average stack concentrations, based on the
previously cited yearly releases, are shown in Table 1-16. The resulting airborne concentrations
represent only stack radionuclide emissions and not offsite airborne radioactivity. In general,
mixed fission products and plutonium emissions have fluctuated about the limits of detection
from year to year.
1-40
-------
Table 1-15. LANL controlled air incinerator emissions^
(Four-Year Summary)
Radionuclides
Pu-238-239
1985
Yearly Releases - Ci/yr^
1986 1987 1988
Mixed-fission
products
1.8E-07
1.9E-06
1.6E-06
7.6E-07
1.4E-07
1.7E-08
2.3E-08
(a) Extracted from the U.S. Department of Energy, Effluent Information System - EPA
Effluent Analysis Report For Calendar Years 1986 to 1988, run date 9/18/89 and paper
titled: The Los Alamos Controlled Air Incinerator for Transuranic and Chemical Waste,
Table titled - TA-50-37 Controlled Air Incinerator: Total Airborne Radioactive Emission
History, not dated.
(b) All values are rounded off and entered as exponential notation; i.e., 1.8E-07 means 1.8x10"
7
(c) Denotes results at or below the limits of detection.
Table 1-16. LANL controlled air incinerator stack radionuclide concentrations00
(Four-Year Summary)
Average Yearly Concentrations - uCi/cc^
Radionuclides
Mixed-fission
products
Pu-238-239
1985
-(c)
3.7E-15
1986 1987
l.OE-14 7.4E-15
9.0E-17 — (c)
1988
5.6E-15
1.7E-16
a) Derived from the U.S. Department of Energy, Effluent Information System - computer run
ALDET001006A, 8/9/90.
(b) Values shown represent stack concentrations and not offsite airborne activity. Total air
volume discharged through stack is 1.9E+8, 2.1E+8, and 1.4E+8 m3 for 1986, 1987, and
1988, respectively. All values are rounded off as exponential notation; i.e., l.OE-14 means
l.OxlO'14.
(c) Denotes results at or below the limits of detection.
1-41
-------
More detailed breakdowns of LANL radioactive emissions, stack concentrations, and waste
volume throughputs are shown in Tables 1-17, 1-18, and 1-19, respectively. This information
and data characterize waste incineration practices from 1979 to 1990. A review of this
information indicates that operational practices, incineration schedules, radionuclide distributions,
activity levels, and waste volumes vary significantly from year to year. Nevertheless, it can be
noted that radionuclide emissions are relatively insensitive to waste characteristics in view of past
incineration practices.
1.4.1.3 Oak Ridge TSCA Incinerator. The Oak Ridge TSCA incinerator was designed to
process uranium contaminated and hazardous organic wastes in compliance with the Toxic
Substance Control Act (TSCA). Other forms of more traditional waste, e.g., LLW, are also
incinerated at this facility. The incinerator is located in a dedicated facility (K-1435), which is
part of the Oak Ridge Gaseous Diffusion Plant, which is designated as K-25.
Off-gas emissions are treated before being released out of the stack. The three major components
of the offgas treatment system are the venturi scrubber, packed-column scrubber, and a wet-
scrubber (ionizing). Emissions are continually monitored by an isokinetic sampling system. The
sampling train consists of a particulate filter and a series of impinger and drying tubes. The
sample is conditioned in order to minimize sample losses. Samples are (c) collected on a weekly
basis and the sampling probe, filter, impingers, and drying tubes are subjected to laboratory
analyses for specific radionuclides of interest.
Pre-operational testing was conducted in August and September 1988. Routine operations were
started later in the fall and were conducted intermittently to primarily test and evaluate
equipment performance and operating conditions.
Airborne emissions for the TSCA incinerator are shown in Table 1-20. As can be seen, data are
available only for 1988 and for radionuclides which were used to conduct the trial burns. Some
waste was, however, incinerated following the completion of the trial tests. Radionuclides
1-42
-------
Table 1-17. LANL Bldg-37 (including CAT) Pu-239 stack releases(a)
Releases®
Year Ending/Period
Activity
Released (Ci)
Stack®
Concentrations (uCi/mL)
1980: 5/16-6/13
1981: 10/31-11/27
1982:
4/16-5/14
8/6-9/3
9/3-10/1
4.0E-09
1.2E-07
8.0E-09
1.3E-08
2.7E-08
6.1E-17
7.3E-15
5.0E-16
7.9E-16
1.6E-15
1983: 3/11-3/18
1985: 12/28-1/4
1/25-2/1
3/15-3/22
3/22-3/29
6/21-6/28
11/15-11/22
11/27-12/6
12/6-12/13
1986: 11/21-11/26
1989: 12/23-1/3
3/24-3/31
7/7-7/14
12/15-12/22
(a) Extracted from U.S. Depai
values are rounded off and
(b) For the years 1984, 1987,
detection.
1.5E-08
1.5E-08
2.3E-08
1.9E-08
1.2E-O8
1.5E-08
9.0E-09
1.5E-08
1.5E-08
1.7E-08
1.2E-08
1.4E-08
1.7E-08
4.0E-08
tment of Energy/LANL submittal dated
entered as exponential notation; i.e. , 4.
and 1988, all reported releases are at
3.7E-15
3.7E-15
5.6E-15
4.7E-15
2.9E-15
3.7E-15
2.1E-15
2.9E-15
3.7E-15
5.7E-15
2.9E-15
5.2E-45
6.5E-15
1.5E-14
11/9/90 (PUC9
OE-09 means 4.
10). All
OxlO-9.
or below the limits of
(c) Values shown represent stack concentrations and not offsite airborne radioactivity.
1-43
-------
Table 1-18. LANL Bldg-37 (including CAI) mixed fission products
(beta) stack releases00
Releases®
Year Ending/Period
1981:
1982:
1983:
1986:
1987:
7/10-8/7
8/7-9/4
10/2-10/30
10/31-11/27
11/27-12/25
12/31-1/8
12/25-1/22
1/22-2/19
2/19-3/19
3/19-4/16
4/16-5/14
4/2-4/9
5/7-5/14
5/14-6/11
6/11-6/18
8/13-8/16
6/11-7/9
7/9-8/6
8/6-9/3
10/1-10/29
10/29-11/26
11/26-12/31
3/11-3/18
6/24-7/1
4/25-5/30
5/30-10/3
6/27-10/3
10/10-11/7
11/7-12/12
12/12-1/23/87
1/23-2/27
2/27-4/3
3/20-3/27
4/3-5/8
5/8-5/29
7/31-9/4
Activity
Released (Ci)
3.1E-08
3.4E-08
5.8E-07
7.6E-08
8.3E-08
l.OE-08
6.8E-08
8.3E-08
9.3E-08
9.1E-08
1.8E-06
1.9E-08
5.9E-08
1.5E-07
1.5E-08
1.1E-08
6.5E-08
1.4E-OB
7.6E-08
3.2E-08
2.7E-08
9.5E-08
3.5E-08
2.7E-08
2.1E-07
5.2E-OB
3.2E-08
l.OE-07
1.4E-07
1.2E-07
1.3E-07
1.2E-07
2.1E-08
1.1E-07
6.3E-08
1.2E-07
Stack(c>
Concentrations (uCi/mL)
2.5E-15
2.1E-15
3.5E-14
4.6E-15
5.0E-15
2.2E-15
3.9E-15
5.0E-15
5.6E-15
5.6E-15
1.1E-15
4.6E-15
1.4E-14
9.1E-15
3.8E-15
6.4E-15
4.0E-15
8.5E-16
4.6E-15
1.9E-15
1.8E-15
4.5E-15
8.5E-15
6.6E-15
2.6E-14
7.1E-16
5.6E-16
6.2E-15
6.7E-15
5.0E-15
6.5E-15
5.9E-15
5.1E-15
5.5E-15
5.1E-15
6.0E-15
1-44
-------
Table 1-18. LANL Bldg-37 (including CAI) mixed fission products
(beta) stack releases(a) (continued)
Releases®
Year Ending/Period
1987:
1988:
1989:
9/4-10/4
10/9-11/13
11/13-12/18
12/18-1/22/88
1/22-2/26
2/26-4/1
4/1-5/6
5/6-6/10
6/10-7/15
7/15-8/19
8/19-9/23
10/28-12/2
12/2-1/3/8
1/6-2/3
2/3-3/10
3/10-4/14
4/14-5/19
6/23-7/28
7/28-9/1
9/1-10/6
Activity
Released (Ci)
2.2E-07
1.4E-07
2.2E-07
2.0E-07
1.6E-07
5.9E-08
9.8E-08
1.7E-07
6.0E-08
9.2E-08
3.4E-08
2.5E-08
1.3E-08
1.1E-07
3.3E-OB
1.4E-07
3.3E-08
7.0E-08
9.0E-09
1.1E-07
Stack(c)
Concentrations (uCi/mL)
1.1E-14
9.4E-15
l.OE-14
1.1E-14
1.2E-14
4.5E-15
7.4E-15
1.3E-14
4.6E-15
7.0E-15
2.6E-15
1.9E-15
l.OE-15
9.6E-15
2.5E-15
l.OE-14
2.5E-15
5.4E-15
8.3E-16
8.2E-15
(a) Extracted from U.S. Department of Energy/LANL submittal dated 11/9/90 (PUC90). All
values are rounded off and entered as exponential notation; i.e., 3.1E-08 means 3.1xia8.
(b) For the years 1984 and 1985, all reported releases are at or below the limits of detection.
(c) Values shown represent stack concentrations and not offsite airborne radioactivity.
1-45
-------
Table 1-19. LANL controlled air incinerator radioactive throughputs00
Date0*
Processed
12/7/79
4/7/80
4/28/80
7/6/81
8/15/82
9/6/84
9/23/86
3/24/87
Nuclides
Pu-239,Am-241
Pu-239,Am-241
Pu-239,Am-241
1-131
Cs-137,Ru-103,
Fe-59,Co-60
1-131
Cs-137,Ru-103,
Fe-59,Co-60
Pu-239,Am-241
Pu-239,Am-241
Beta emitters
Activity (Ci)
<2.3E-04
8.0E-05
4.5E-03
1.6E-02
4.0E-03
1.6E-02
4.0E-03
7.1E-02
1.4E-O1
6.2E-02
Total Waste(c)
Quantity (kg)
229
5
277
290
145
145
145
100
448
989
(a) Extracted from U.S. Department of Energy/LANL submittal dated 11/9/90 (PUC90). All
values are rounded off and entered as exponential notation; i.e., 2.3E-04 means 2.3X104.
(b) No data available for the years 1983, 1985, and 1988.
(c) Values represent total waste quantities incinerated for the given dates. Radioactivity may in
fact be contained in smaller waste volumes, typically less than 1 percent.
1-46
-------
Table 1-20. Oak Ridge TSCA incinerator emissions and waste feed
radioactivity for 1988(a)
Radionuclides
Tc-99
U-234
U-235
U-238
Total-U
Th-228
Th-230
Np-237
Pu-238
Pu-239
Emissions - Ci/yr00
1.6E-03
4.9E-04
2.5E-05
5.7E-04
ND
ND
ND
ND
ND
ND
Waste Feed - Ci(c)
9.5E-05
ND(d)
ND
ND
4.0E-02
l.OE-06
8.8E-07
1.4E-07
4.8E-07
4.8E-07
(a) Extracted from the U.S. Department of Energy, Effluent Information System - EPA
Effluent Analysis Report For Calendar Years 1986 to 1988, run date of 9/18/89.
(b) All values are rounded off and entered as exponential notation; i.e., 1.6E-03 means
1.6X103.
(c) Associated waste volume: solid waste, 160 cubic feet; liquid waste, 20,490 gallons
Extracted from DOE 10/5/90 submitted.. ..
(d) ND means no data.
percent for each of the remaining two uranium isotopes. These reported radionuclide emissions
are associated with the processing of 160 cubic feet of solid waste and 20,490 gallons of liquid
waste.
Stack radionuclide concentrations, based on the previously cited yearly releases, are shown in
Table 1-21 for 1988 only. The incinerator was not operating in the previous years. The
resulting airborne concentrations reflect primarily test burn trials and do not represent stack
offsite airborne radioactivity.
.1.4.1.4 Brookhaven National Laboratory LLW Incinerator. The Brookhaven National
Laboratory (BNL) incinerator is located in the Hazardous Waste Management Facility (Bldg
1-47
-------
Table 1-21. Oak Ridge TSCA incinerator stack radionuclide
concentrations - 1988(a)
Radionuclides
Average Yearly
Concentrations - uCi/cc®
Tc-99
U-234
U-235
U-238
Alpha activity
Beta activity
Gamma activity
8.6E-11
2.6E-11
1.3E-12
3.0E-11
2.6E-12
1.2E-12
2.2E-15
(a) Derived from the U.S. Department of Energy, Effluent Information System - computer run
OUKK001050A of 8/9/90 and extracted from DOE/BNL 10/5/90 submittal. All values are
rounded off and entered as exponential notation; i.e., 8.6E-11 means 8.6 x 10"11
(b) Values shown represent stack concentrations and not offsite airborne activity. Total air
volume discharged through stack is 1.9E+7 m3 for 1988. Associated waste volume: solid
waste, 160 cubic feet; liquid waste, 20,490 gallons.
. 444). This incinerator is used to process low-level radioactive waste generated by various
facility operations and research activities.
The incinerator is not equipped with off-gas treatment or air monitoring systems. Radionuclide
emissions are based on the radionuclide distributions and inventories
characterizing the waste. Daily and weekly airborne monitoring is performed at two sampling
locations situated near the facility's site boundary.
Airborne effluent releases for the years 1986 to 1988 are shown in Table 1-22. Seventeen
radionuclides were reported released between 1986 and 1988. In 1988, only H-3, C-14, Cr-51,
Tc-99, Sn-113, 1-125, and 1-131 were reported by BNL. In general, H-3 (about 95 percent) and
Sn-113 (nearly 72 percent) are the most predominant radionuclides reported over the 3-year
span.
1-48
-------
Table 1-22. Brookhaven National Laboratory low-level radioactive
waste emissions00
Radionuclides
1986
Yearly Releases - Ci/y00
1987
1988
H-3
C-14
P-32
S-35
Cr-51
Mn-54
Fe-55
Co-57
Fe-59
Tc-99
Tc-99m
Ru-103
Sn-113
Sn-117m
1-125
1-131
Tl-201
9.4E-02
7.7E-04
2.5E-04
5.7E-04
1.1E-04
l.OE-05
5.1E-03
2.1E-05
O.OE-OO
l.OE-04
2.0E-04
1.2E-05
2.0E-04
4.2E-05
5.2E-04
2.1E-05
2.1E-05
1.6E-O1
2.2E-04
9.0E-07
2.5E-03
1.5E-03
O.OE-OO
O.OE-OO
O.OE-OO
l.OE-06
4.2E-05
l.OE-05
O.OE-OO
2.8E-03
O.OE-OO
8.9E-05
1.7E-04
O.OE-OO
5.6E-05
3.0E-06
O.OE-OO
O.OE-OO
5.0E-07
O.OE-OO
O.OE-OO
O.OE-OO
O.OE-OO
5.0E-09
O.OE-OO
O.OE-OO
2.3E-04
O.OE-OO
2.0E-05
l.OE-05
O.OE-OO
(a) Extracted from the U.S. Department of Energy, Effluent Information System - EPA
Effluent Analysis Report For Calendar Years 1986 to 1988, run date of 9/18/89.
(b) All values are rounded off and entered as exponential notation; i.e., 7.7E-04 means 7.7xlQ-
Data characterizing monthly radionuclide emissions are shown in Table 1-23. Radionuclides and
radioactivity releases are given for the years 1987, 1988, and 1989. This information reveals
that waste was incinerated during only a few months each year, i.e., 5 months in 1987, and 3
months in 1988 and 1989. Some radionuclides are present in each burn while others are not.
For example, H-3, C-14, C-51, Sn-113, and radio-iodines are the most often cited nuclides. In
terms of radioactivity released on a monthly basis, H-3, P-32, S-35, Cr-51, Sn-113, and 1-125
are by far the most predominant.
1-49
-------
Table 1-23. Brookhaven National Laboratory low-level radioactive waste monthly
incinerator emissions for 1987-1989®
Part I: 1987 Monthly Burns and Releases - mCi®
Radionuclides May June July
August
December
H-3
014
P-32
S-35
Cr-51
Fe-59
Tc-99
Tc-99m
Sn-113
1-125
1-131
Part II:
1.6E+O1 »(c)
1.5E-O1 7.0E-02
__
5.0E-03
6.2E-02 5.0E-03 5.0E-03
l.OE-03
1.2E-02 2.0E-02
l.OE-02
l.OE-02
4.6E-02 3.0E-03 6.0E-03
1.6E-02 l.OE-05
1988 Monthly Burns and Releases - mCi00
Radionuclides February September
H-3
C-14
Cr-51
Sn-113
1-125
1-131
»(c) l.OE-03
3.0E-03
'
2.3E-O1
1.1E-02
l.OE-02
1.5E+O1 1.3E+02
—
9.0E-04
2.5E+OO
1.4E+OO 5.3E-02
. __
l.OE-02
__
2.8E-OO
1.2E-02 2.2E-02
5.0E-03 1.5E-01
November
5.5E+02
—
5.0E-04
—
8.0E-03
(a) Extracted from the U.S. Department of Energy, Effluent Information System - EPA
Effluent Analysis Report For Calendar Years 1986 to 1988, run date 9/18/89 and 10/4/90
DOE/BNL Submittal.
(b) All values are rounded off and entered as exponential notation; i.e., 7.7E-04 means
7.7x10^.
(c) Signifies that no data were reported for that month.
1-50
-------
Table 1-23. Brookhaven National Laboratory low-level radioactive waste monthly
incinerator emissions for 1987-1989
-------
Table 1-24. Brookhaven National Laboratory low-level radioactive waste
incinerator stack concentrations00
Radionuclides
H-3
C-14
P-32
S-35
Cr-51
Mn-54
Fe-55
Co-57
Fe-59
Tc-99
Tc-99m
Ru-103
Sn-113
Sn-117m
1-125
1-131
Tl-201
Average Yearly Concentrations - uCi/cc®
1986 1987 1988
l.OE-08
8.6E-11
2.8E-11
6.3E-11
1.2E-11
LIE- 12
5.7E-10
2.3E-12
O.OE-00
1.1E-11
2.2E-11
1.3E-12
2.2E-11
4.7E-12
5.8E-11
2.3E-12
2.3E-12
1.8E-08
2.4E-11
l.OE-13
2.8E-10
1.7E-10
O.OE-00
O.OE-00
O.OE-00
L1E-13
4.7E-12
1.1E-12
O.OE-00
3.1E-10
O.OE-00
9.9E-12
L9E-11
O.OE-00
6.2E-12
3.3E-13
O.OE-00
O.OE-00
5.6E-14
O.OE-00
O.OE-00
O.OE-00
O.OE-00
5.6E-16
O.OE-OO
O.OE-00
2.6E-11
O.OE.OO
2.2E-12
LIE- 12
O.OE-00
(a) Derived from the U.S. Department of Energy, Effluent Information System - computer run
CBLIR72445A, 8/9/90. . . m . . ,
(b) Values shown represent stack concentrations and not offsite airborne activity. Total air volume
discharged through stack is 9.0E+6 m3 for each reported year. All values are rounded off and
entered as exponential notation; i.e., l.OE-08 means l.Oxia8.
treatment system. The off-gas treatment system consists of a baghouse, pre-filter, and single bank of
HEPA filters. The stack servicing the heat-exchanger is not equipped with an off-gas treatment system
since this exhaust stream does not mix with combustion gases.
Stack releases are continuously monitored by an airborne radiation monitoring system. The sample is
pulled through a particulate filter. Each filter is changed weekly and is analyzed monthly, as a
composite sample. Analytical procedures include the determination of gross alpha and gross beta
1-52
-------
include primarily Tc-99, U234, U-235, and U-238. Tc-99 makes up about 60 percent of the total
radioactivity released, and uranium, except for U-235, makes up 20 activity and the identification of
specific radionuclides. The results of these analyses are reported and compiled monthly and yearly by
INEL.
Incinerator emissions are shown in Table 1-25. Airborne emissions typically include Co-60, Cs-137,
Sr-90, Mo-99, and Mn-54. Cesium and strontium are the major radionuclides routinely released; they
comprise about 70 percent of the total radioactivity. A review of the data indicates that mixed fission
products (gross beta) and mixed alpha products (gross alpha) are the most predominant sources of
radioactivity. On average, the WERF incinerator releases about 1,400 uCi of total radioactivity per
year, based on 1987 INEL data (INEL88a,b). Total activity, shown as gross alpha and gross beta, and
Sr-90 have been given for each of the four reported years. All other nuclides are present at much lower
concentrations. It can be noted that emissions have fluctuated over the four reported years. These
concentrations represent airborne radioactivity at the point of release and not at distant downwind
locations.
Table 1-25. Idaho Engineering Laboratory WERF incinerator emissions00
Radionuclides
Gross alpha
Gross beta
Sr-90
Cs-137
Yearly Stack Releases - Ci/yr®
1986 1987 1988
6.9E-09
1.3E-07
1.3E-07
»-(c)
3.3E-09
3.2E-08
7.9E-07
2.0E-07
7.9E-08
1.1E-06
1.4E-06
1989
5.7E-08
1.1E-06
9.4E-08
^ ' J 7 —.,——. ^^M,U^.VM.W. v v » » uubw J-TJ.uaAU^ Will WAIL .L11J. \_UAlidUAJiI VJ YOlC-Ill. J.Z7QO UCtUl Ul J ]
18, 1990, and DOE/INEL submittal dated 10/5/90.
(b) All values are rounded off and entered as exponential notation; i.e., 6.9E-09 means 6.9xia9.
(c) Signifies that no data were reported.
Waste volumes and radionuclide concentrations are shown in Tables 1-26 and 1-27. Although
several radionuclides are listed, waste activity is dominated by unidentified alpha emitters and
mixed fission products. The waste volume processed yearly varied over a narrow range of
1-53
-------
Table 1-26. Idaho Engineering Laboratory WERF incinerator monthly
emissions and processed waste volumes*1
Parti: 1987 Waste Volume and Activity Releases
Volume Activity Released - Ci0*
Month
Jan.
Feb.
Mar.
Apr.
May
Jun.
Jul.
AUE.
4 AW^«
Sept.
Oct.
Nov.
Dec.
Part II: 1988
Month
Jan.
Feb.
Mar.
Apr.
r
May
J
Jun.
Jul.
Aug.
Sept.
Oct.
Nov.
Dec.
(Cu. meters)
— to
279
_-.
210
304
118
122
218
127
100
—
Waste
Volume and
Volume
(Cu. meters)
241
249
116
127
240
137
118
99
247
118
133
172
Cs-137 Sr-90 Gross Alpha Gross Beta-
5.6E-08 3.2E-09
1.6E-08 6.1E-09
1.1E-09 4.2E-09
1.6E-07 5.6E-09
8.9E-08 2.9E-09
5.0E-08 1.6E-07 7.9E-09
l.OE-07 6.4E-08 6.6E-09
2.4E-08 4.2E-09
5.0E-08 l.OE-07 5.9E-09
2.9E-08 7.2E-09
8.8E-08 3.9E-09
7.8E-09
Activity Releases
Activity Released
Sr-90 Gross Alpha
1.6E-07 l.OE-08
1.2E-07 1.9E-OB
2.9E-08 5.9E-1O
2.9E-08 1.3E-09
2.4E-08 5.5E-09
2.6E-12
6.7E-08 7.9E-09
9.9E-07 5.8E-09
3.8E-09 5.5E-09
1.3E-08 9.3E-09
1.4E-08 5.8E-09
7.3E-09
4.0E-08
3.4E-08
2.3E-08
3.5E-08
4.0E-08
9.8E-08
7.9E-08
5.6E-08
1.2E-07
7.8E-08
4.5E-08
4.8E-08
-Ci
Gross Beta
9.9E-08
2.0E-07
8.6E-09
1.6E-08
6.8E-08
5.4E-08
l.OE-07
6.0E-08
9.0E-08
1.3E-07
6.8E-08
1.8E-07
1-54
-------
Table 1-26. Idaho Engineering Laboratory WERF incinerator monthly emissions and
processed waste volumes^, (Continued)
Part III: 1989 Waste Volume and Activity Releases
Month
Jan.
Feb.
Mar.
Apr.
May
Jun.
Jul.
Aug.
Sept.
Oct.
Nov.
Dec.
Volume
(Cu. meters)
__
5
—
251
244
119
1 10
230
239
—
209
217
Sr-90
1.9E-08
3.8E-08
3.3E-09
—
3.9E-1O
1.8E-10
.—
~
1.4E-08
—
2.0E-08
—
Activity
Gross Alpha
2.7E-09
1.4E-08
6.1E-09
__ .
3.5E-09
1.8E-09
3.6E-09 ;
5.0E-09
4.3E-09
8.5E-09
—
7.2E-09
Released - Ci
Gross Beta
5.7E-08
2.3E-07
4.3E-08
6.0E-08
6.7E-08
2.4E-08
1.5E-07
9.3E-08
5.9E-08
6.2E^08
1.8E-07
1.1E-07
Obtained from DOE/INEL, submittal dated 10/5/90.
All values are rounded off and entered as exponential notation; i.e., 5.6E-08 means
5.6x10-*.
Signifies that no data were reported.
Table 1-27. Idaho Engineering Laboratory WERF incinerator low-level radioactive
waste radionuclide concentrations^
Radionuclides
1986
Average Waste Concentrations -
1987
1988
Co-60
Nb-95
Zr-95
Cs-134
Cs-137
Ce-144
Beta/Gamma
Mixed Fission Products
Mixed Alpha Emitters
3.3E-07
2.7E-07
1.4E-07
2.9E-07
1.2E-06
1.9E-07
1.2E-07
1.1E-03
2.9E-04
1.3E-04
O.OE-OO
O.OE-OO
O.OE-OO
O.OE-OO
O.OE-OO
O.OE-OO
l.OE-03
2.3E-05
3.9E-06
O.OE-OO
1.5E-07
2.5E-08
1.8E-07
8.2E-09
O.OE-OO
7.7E-04
2.9E-05
(a)
Derived from the U.S. Department of Energy, Effluent Information
System - computer run IIAWR76055A, 8/9/90.
Total waste volume processed in each year is 1,611, 1,564, and 1,465 m3
for 1986, 1987, and 1988, respectively. All values are rounded off and entered as
exponential notation; i.e., 3.3E-07 means 3.3xlO'7-
1-55
-------
1,465 to 1,624 entered as exponential notation; i.e., 3.3E-07 means 3.3xlO'7. cubic meters, and
averaged about 1,570 m3. On a monthly basis, the processed waste volumes vary from about
5 to 250 cubic meters, averaging about 130 cubic meters per month over the four reported years.
Using the information given in Tables 1-27 and 1-28, the overall incinerator decontamination
factor (DF) has been estimated for mixed fission and alpha products, see Table 1-29. The DF
is expressed as the ratio of the amount of radioactivity introduced into the incinerator to the
amount that is observed on the discharge side of the offgas treatment system. The DF represents
the overall effectiveness of the incinerator in retaining radioactivity in ashes and within off-gas
treatment systems. A review of Table 1-29 indicates that DFs on the order of 1O+1° to 10+11
are routinely attainable. These results are generally better than those experienced at other
facilities. A survey conducted by the IAEA reported DFs ranging from as low as 10 to as high
as 10+7 see subsection 1.3.1 for details (IAEA89).
INEL is in the process of finalizing the installation of a new incinerator facility, known as the
PREPP. The incinerator is located within INEL's TAN/TSF area. The PREPP incinerator is
currently not processing any radioactive waste. Accordingly, there are no reported releases for
this facility.
The PREPP incinerator may eventually process transuranic waste, primarily including Pu-239,
Pu-240, Pu-241, and Pu-242, Am-241, Cm-241, and U-233. The process is designed to convert
TRU and hazardous waste in a form compatible for eventual disposal at the WIPP facility,
located in Carlsbad, New Mexico.
1.4.1.6 Savannah River Site Beta-Gamma Incinerator. The Savannah River Site Beta-Gamma
Incinerator (BGI) has been used to process solid low-level radioactive waste generated by various
plant operations and to treat liquid waste, such as spent Purex solvents. The incinerator, located
in Building 230H, has been intermittently operated over the past few years and has not been
running since 1989. The BGI will be replaced by the Consolidated Incineration Facility, which
is scheduled to become operational in 1993. This facility will process hazardous and mixed
waste in addition to low-level radioactive waste.
1-56
-------
Table 1-28. Idaho Engineering Laboratory WERF incinerator
stack concentrations00
Radionuclides
1986
Average Yearly Concentrations -
1987 1988 1989
Gross alpha
Gross beta
Sr-90
Cs-137
4.2E-16
8.1E-15
7.7E-15
-(c)
5.5E-16
5.4E-15
1.1E-14
2.8E-15
8.8E-16
1.2E-14
1.6E-14
—
3.7E-16
7.3E-15
6.0E-16
—
(a) Derived from the U.S. Department of Energy, Effluent Information
System - computer run HAWR76055A of 8/9/90, and DOE/INEL submittal
dated 10/5/90.
(b) Values shown represent stack concentrations and not offsite airborne
activity. Total air volume discharged through stack is 1.7E+7, 6.0E+6,
8.9E+7, and 1.6E+8 m3 for 1986, 1987, 1988, and 1989, respectively. All
values are rounded off; entered as exponential notation; ie., 4.2E-16
means 4.2xlO"16.
(c) Signifies that no data were reported.
Table 1-29. Idaho Engineering Laboratory WERF incinerator overall
decontamination factor''0
Ratio of Waste to Stack Concentrations0"5
Waste/Air Ratio Waste/Air Ratio Waste/Air Ratio
Nuclides
Gross
alpha:
Gross beta
&MFP:
1986
10+u
10+1°
1987
10+io
10+n
1988
10+1°
10+io
(a) Derived from the previous two tables, see text for details.
(b) Values shown represent the ratio of waste activity to its corresponding stack concentration.
All values are rounded off and entered as exponential notation; i.e., 10+" means about
1.0xlO+u.
1-57
-------
Airborne effluents from the BGI were treated by an off-gas system before being released. The
treatment system was equipped with a dry quencher (air-atomized) to cool combustion gases, a
baghouse, and a set of HEP A filters. Off-gases were released via a 60-foot stack with an exhaust
flow rate of 10,000 cubic feet per minute.
The stack effluent radiological monitoring system was comprised of a continuous sampling pump
and particulate filter system. Particulate filters were periodically removed and analyzed for gross
beta and gamma activity. Such filters were also subjected to gamma spectroscopy analyses to
identify specific nuclides.
Table 1-30 presents a summary of gaseous effluent releases for 1986, 1987, and 1988. Tritium
is reported as the primary radionuclide for the three given years. Other radionuclides have also
been reported, but at much lower activity levels. Such radionuclides include: Ru-106,1-131, Cs-
134, Cs-137, Ce-144, Am-241, Am-243, Cm-242, Cm-244, and unidentified beta/gamma
emitters. Together these radionuclides comprise about l.OE-5 Curies in 1986, <4.0E-5 Curies
in 1987, and
-------
The corresponding incinerated waste volumes are shown in Table 1-31. In all cases, the
incinerator was operated only a few months each year; 6 months in 1986; 7 months in 1987, and
1 month in 1988. Solid wastes were incinerated in 1986, while H-3 contaminated oil was
incinerated during each of the three reported years. The largest volume of oil and the highest
H-3 radioactivity levels were incinerated in 1987.
1.4.2 Commercial Incinerators
1.4.2.1 Scientific Ecology Group Incinerator. The Scientific Ecology Group (SEG) incinerator,
located in Oak Ridge, is designed to process low-level radioactive waste on a commercial basis.
The SEG incinerator is based on a modified European design. The incinerator is used as part
of a larger waste management program which includes waste processing, sorting, compaction,
etc.
Airborne effluent releases and radionuclide distributions in waste and incinerator ashes are given,
see Table 1-32, for the last 3 months of 1989. As can be noted, data parameters are incomplete
for many of the listed radionuclides. In terms of airborne emissions, H-3 and C-14 are by far
the most predominant. Radionuclide emissions for a 3-month period are shown in Table 1-33.
The emissions are associated with the processing of H-3 contaminated oils. Releases, for the last
quarter of 1989, are primarily dominated by C-14 and H-3. All other nuclides are present in
much lesser amounts, typically by four or more orders of magnitude. Some radionuclides, not
listed in Table 1-33, were reported to be at or below limits of detection, and were not reported
by SEG. The decontamination factors (DF) were calculated for those radionuclides with reported
activity for both waste and stack emissions. The DF is expressed as the ratio of radioactivity
reported in waste to that observed in stack emissions. The estimated DFs typically range from
1,000 to 10+u except for H-3, C-14, and 1-129. For these radionuclides, the DF is one
1.4.2.2 Advanced Nuclear Fuels Incinerator. The Advanced Nuclear Fuels (ANF) facility is
located in Richland, WA. The ANF Specialty Fuels Building houses a dual-chamber controlled-
1-59
-------
Table 1-31. Savannah River Site beta-gamma incinerator processed
waste volume and activity: 1986-1988(a)
Part I: 1986 Waste Volumes and H-3 Activity
Month
Processed
Mar.
May
Jun.
Oct.
Nov.
Dec.
Total
Part n: 1987 Waste Volumes
May
Jun.
Jul.
Aug.
Sept.
Nov.
Dec.
Total
Part IH: 1988 Waste Volume
Jan.
Solid Waste
(cubic feet)
3,664
2,608
443
80
48
—
6,843
and H-3 Activity
—
—
—
—
and H-3 Activity
Liquid
Oil - Gal.
—
—
_«
—
435
3,600
4,035
4,276
6,950
2,995
504
400
3,800
3,704
22,629
1,312
Waste
H-3 - Ci
—
__
—
49
409
458
485
789
335
57
45
431
420
2,562
149
(a) Data obtained from DOE/SRS staff, submittal dated 9/28/90. Only H3 has been reported
for the waste cited above. Incinerator shutdown Jan. 1988.
1-60
-------
Table 1-32. SEG incinerator waste, emissions, ash radionuclide distribution for 1989(a;
Radionuclides
H-3
C-14
Cr-51
Mn-54
Fe-55
Fe-59
Co-57
Co-58
Co-60
Ni-63
Zn-65
Sr-89
Sr-90
Nb-95
Zr-95
Tc-99
Ag-llOm
Sn-113
Te-125m
Sb-124
Sb-125
1-129
1-131
Ce-144
Cs-134
Cs-137
Hf-181
Tl-201
Ra-226
Th-232
U-238
Pu-241
Am-241
Cm-242
TRU
Releases or Contents - Ciw DF Ratio
Waste Emissions Ashes Waste/Emission
1.1E-02
2.2E-02
1.5E-O1
1.5E-O1
8.2E-O1
1.8E-02
2.2E-04
3.5E-O1
5.3E-O1
2.4E-01
5.8E-02
1.3E-03
l.OE-02
2.5E-02
9.4E-03
5.2E-04
6.1E-03
3.4E-05
1.5E-06
2.5E-03
6.4E-04
5.1E-06
2.0E-08
2.0E-03
2.3E-O1
7.3E-O1
5.2E-05
2.1E-05
ND
3.3E-07
1.3E-03
2.5E-04
ND
2.0E-07
3.4E-06
1.1E-02
2.2E-02
ND
1.2E-07
ND
ND
ND
ND
1.4E-06
ND
ND
ND
1.1E-14
ND
ND
1.5E-07
1.1E-06
ND
ND
ND
2.6E-07
5.1E-06
2.0E-14 ,
ND
5.3E-07
3.4E-06
ND
ND
ND
ND
4.8E-09
ND
ND
ND
ND
ND
ND
9.9E-03
1.5E-02
ND
ND
2.5E-04
ND
1.1E-O1
ND
3.5E-03
O.OE-OO
ND
ND
2.3E-03
ND
6.6E-03
ND
ND
ND
3.9E-03
ND
ND
1.8E-03
6.1E-03
2.6E-02
ND
ND
1.2E-06
ND
1.3E-03
ND
l.OE-04
ND
ND
1
1
1O6
_
10s
_
_
1011
_
103
103
•
103
1
106
10s
105
10s
-
(a) Extracted from correspondence between SEG and U.S. EPA Region VI, letter not dated.
Represents revised data for the months of Oct., Nov., and Dec., 1989 only,
(b) All values are rounded off and entered as exponential notation; i.e., 1. 1E-02 means
l.lxlO"2. ND means no data.
1-61
-------
Table 1-33. SEG incinerator stack emissions - 4th Quarter 1989**
Radionuclides
October
Stack Releases - Ci(b)
November
December
H-3
C-14
Mn-54
Co-60
Sr-90
Tc-99
Ag-llOm
Sb-125
1-129
1-131
Cs-134
Cs-137
Total-U
(a) Extracted from correspondence
Represents revised data for the
1.7E-11
1.8E-10
O.OE-OO
O.OE-OO
O.OE-OO
1.5E-07
O.OE-OO
6.4E-04
O.OE-OO
1.9E-14
O.OE-OO
O.OE-OO
4.8E-09
5.2E-03
4.9E-03
O.OE-OO
2.8E-07
2.4E-14
8.2E-13
5.8E-07
2.6E-07
O.OE-OO
O.OE-OO
3.6E-07
2.5E-06
2.1E-13
5.5E-02
1.7E-02
1.2E-07
1.1E-06
8.8E-14
6.7E-13
4.2E-07
3.9E-03
5.1E-06
O.OE-OO
1.7E-07
9.3E-07
2.7E-13
between SEG and U.S. EPA Region VI, letter not dated.
months of Oct.,
(b) For the month of October, emissions represent
Nov., and Dec., 1989
releases from both the
only.
incinerator and oil
burner. November and December emissions are for the incinerator only; oil burner was
shutdown. Other radionuclides, if present, were below the detection limits and were,
therefore, not reported by SEG. All values are rounded off and entered as exponential
notation; i.e., 1.7E-11 means 1.7xlO'u.
Packages destined for incineration are sorted and then surveyed to assess the amount of uranium
present. All waste fed to the incinerator is packaged in cardboard boxes to facilitate the
combustion process and minimize ash generation. Ash generated after each burn is collected and
assayed for uranium (UO^ content. If the uranium concentration is found to be elevated, the ash
is subjected to a leaching process to recover the uranium. If uranium is present at low
concentrations, ashes are disposed of at a low-level radioactive waste disposal site.
The ANF incinerator off-gas treatment system is comprised of several components, which
include: a quench column, a venturi scrubber, a packed column, a mist eliminator, a re-heater,
1-62
-------
and a set of HEP A filters. The stack monitoring system consists of a continuous sampling train,
which pulls a sample through a paniculate filter paper. The filter is removed on a weekly basis
and analyzed for alpha radioactivity. Current radionuclide emissions are typically around 10'15
uCi/mL (ANF90).
Waste volumes processed over the past 2 years are summarized in Table 1-34. A total of about
49,100 cubic feet of solid waste and 2.9 million gallons of liquid waste were processed in 11
burn cycles. The duration of a typical burn cycle ranges from about 100 to 1,400 hours,
averaging about 600 hours. The incineration of these wastes resulted in the generation of 538
cubic feet of ash. A total of 4,748 kg of uranium was processed and recovered during this two-
year period. The overall volume reduction factor, using solid waste and spent HEP A filter data,
is estimated to be about 100.
Not included in these totals, ashes excepted, are the waste volumes and amounts of uranium
associated with the incineration of spent HEPA filters. Spent HEPA filters from the off-gas
treatment system are periodically replaced and processed to reduce waste volumes and recover
any trapped uranium. The total volume of spent HEPA filters is about 3,300 cu.ft., also
generated over the 11-burn cycle. A total of 7.3 kg of uranium was recovered from the
incineration of spent filters.
1-4-3 Institutional Incinerator Operations
Typical incinerator effluents were estimated from the survey data described earlier (CRC84).
The nuclear fuel-cycle incinerators were excluded because they are not typical of the large
number of institutional facilities with incinerators, represent only a small number of facilities,
and process unique waste forms. A sample of institutional licensees that incinerate waste was
selected and the activities of the incinerated waste were averaged. For estimating effluents, it
was assumed that 100 percent of the activity incinerated was vaporized and released in the
1-63
-------
Table 1-34. Advanced Nuclear Fuels solid and liquid waste
volumes and uranium mass (a)
Runw
No.
1
2
3
4
5
6
7
8
9
10
11
Total:
Solid Waste(c)
VoUft3) U(kg)
1,418
850
1,530
1,495
3,773
6,580
8,743
2,887
7,210
9,534
5,054
49,074
2.0
21.5
34.1
46.9
170.7
496.6
860.8
288.9
663.4
1,009.0
598.5
4,192.4
Liquid Waste
Vol.(gal) U(kg)
146,035
147,150
145,695
86,112
184,873
459,967
698,927
117,931
335,018
387,799
233,452
2,942,959
0.063
0.779
0.662
1.275
2.633
5.414
10.834
4.256
7.948
13.502
7.667
55.033
Ashes
Vol.(ft3) U(Kg)
4.5
4.0
6.8
10.9
31.4
63.0
114.6
36.9
77.0
120.0 1
68.5
537.6
1.6
25.7
46.9
59.1
159.1
490.9
994.5
384.6
742.9
,145.3
697.6
4,748.2
(a) Extracted from ANF submittal dated 8/14/90. See text for details (ANF90).
(b) Data represent incinerator operation from 8/26/88 to 7/16/90. Each burn cycle is about 600
hrs, on the average.
(c) This tabulation does not include the incineration of spent HEPA filters which are
periodically removed from the incinerator off-gas treatment system. This total volume
amounts to about 3,300 cu.ft. generated over the 11 runs cited above. A total of 7.3 kg of
uranium was recovered from the incineration of such spent filters.
1-64
-------
exhaust. This approach is in fact used by many facilities; it is simply assumed that all of the
radioactivity is exhausted through the stack (EGG80). The amount of radioactivity which is
introduced in the incinerator is limited, knowing its operating characteristics, to ensure that
airborne radioactive releases do not exceed the maximum permissible concentrations allowed by
State or Federal regulations. This approach is usually very conservative in assessing the impact
at downwind locations for most radionuclides, with the exception of tritium, carbon-14, and
radioiodines. Many facilities also have no off-gas scrubbers or filters and do not routinely
monitor airborne emissions.
The predominant nuclides are shown in Table 1-35. The average release rates are given in
curies per year. Tritium and sulfur-35 are the most predominant radionuclides. Carbon-14,
phosphorus-32, chromium-51, and iodine-125 are characterized by lower release rates.
1.4.4 Studsvik Incinerator Operations
Table 1-36 summarizes emissions from the Studsvik Incinerator Facility located in Sweden
(IAE89). This facility processes wastes mainly from nuclear power plants, hospitals, and fuel
fabrication facilities. Some of the waste also comes from other European countries. The IAEA
report notes that the cited yearly releases are all in compliance with Swedish National Institute
of Radiation Protection Standards. This facility was chosen because it processes waste of
varying forms and the radionuclide distribution includes alpha emitters. The incinerator
(multistage excess air system) does not use HEPA filters, but rather relies on a bag filtration
system made of polytetrafluorethylene. In 1983, the radionuclide emissions were associated with
the processing of 355 metric tons of waste (HET90). In 1984, the total waste volume
incinerated was reported to be 435 metric tons (HET90). For either year, releases consist
primarily of H-3 and 1-125, while the other radionuclides are lower by several orders of
magnitude.
1-65
-------
Table 1-35. Effluent release rates for low-level radioactive waste
incinerators - 1984
Major
Radionuclide
Average Release
Rate (Ci/yr)
H-3
C-14
P-32
S-35
Cr-51
1-125
0.1
0.05
0.07
0.1
0.01
0.015
(a) Values are as reported and are not adjusted for the survey response rate. Source: CRCPD
Survey, DOE/ID/12377, 1984 (CRC84).
Table 1-36. Radionuclide emissions from the Swedish Studsvik
Incinerator Facility (a)
Airborne Emissions (Ci/yr)
Radionuclide
H-3
Co-60
Ag-llOm
1-125
1-131
Cs-134
Cs-137
Alpha emitters
Waste quantity
processed (metric tons)
1983
1.4E+0(b)
—
3.0E-4
8.9E-2
5.9E-4
2.5E-5
1.9E-4
9.5E-6
355
1984 (Jan-Aug)
4.3E+1
2.7E-4
—
1.2E-1
3.3E-3
—
7.3E-5
—
435 (full year)
(a) Extracted from IAEA Technical Report Series No. 302, Table XXIX, 1989 (IAE89) and
technical correspondence (HET90).
(b) Exponential notation, 1.4E+O means 1.4 and 1.2E-1 means 0.12.
1-66
-------
1.5 OPERATIONS AND MAINTENANCE PRACTICES AND PROCEDURES
Operations and maintenance practices vary with the particular type of incinerator. Specific
practices pertaining to the various components of incinerator systems are beyond the scope of
this report. However, a few major overall considerations are described below.
A fundamental characteristic of incinerators is that they are designed to function best under
strictly controlled, predictable, steady-state conditions. Uncontrolled variations in the quantity
and physical/chemical characteristics of the waste feed material can have a significant negative
effect both on incinerator performance in terms of the combustion process and on the potential
for air emissions. It is difficult, if not impossible, for incinerators to be capable of responding
rapidly to wide fluctuations in the nature of the feed in such parameters as btu content, ash
quality and quantity, pH of the off-gases, etc. Designing the unit for worst-case conditions it
may encounter for each parameter will not be a satisfactory solution because optimizing for one
condition will likely adversely influence performance in another area. For example, maintaining
the upper limit of temperature for one type of waste will lead to slagging with other types of
waste. Thus, analysis and control of feed material is a crucial aspect of operations. For
radioactive waste, this involves the monitoring of the physical/chemical nature of the feed
(sorting of low-level waste according to combustibility, shredding of dry material, etc.), as well
as its activity levels and radionuclide content.
Process monitoring and control procedures are used to ensure the proper functioning of the
actual incineration process. Chapter 2 describes the focus areas for these procedures. The need
for attention to following proper procedures in monitoring, treatment, and handling of off-gases
and solid residues (ash) obviously is of particular importance for radioactive and mixed waste
incineration. Monitoring technologies are described in Chapter 3.
1-67
-------
1.6 REGULATORY REQUIREMENTS
1.6.1 Nuclear Regulatory Commission Licensing
The Atomic Energy Act (AEA) of 1954, as amended, and the Energy Reorganization Act of
1975 govern the Nuclear Regulatory Commission's (NRC's) authority to regulate incineration
of low-level radioactive waste (LLW). The NRC grants licenses for purposes authorized by the
AEA, subject to favorable findings related to public health and safety, protection of the
environment, and the common defense and security. The NRC implements the AEA with
respect to incineration through Title 10 of the Code of Federal Regulations Parts 20, 30, 40, 50,
51, and 70. The NRC exercises its statutory authority over license holders by imposing a
combination of design criteria, operating parameters, and license conditions at the time of
construction and licensing. It ensures that the license conditions are fulfilled through inspection
and enforcement activities.
By formal agreement with the NRC, a total of 29 States have assumed regulatory responsibility
over byproduct materials, source materials, and limited quantities of special nuclear materials.
These States, in addition to the responsibilities granted by the NRC, have in some cases adopted
additional regulations: For example, Natural and Accelerator-Produced Radioactive Material
(NARM) is covered by some State regulations, although there are presently no universally
applicable regulations for NARM materials.
The NRC's regulations requke an analysis of probable radioactive effluents and their effects on
the population near licensed facilities. The NRC also ensures that all exposures are as low as
is reasonably achievable (ALARA) by imposing design criteria for effluent control systems and
equipment. After a license has been issued, licensees must monitor their emissions and set up
an environmental monitoring program to ensure that the design criteria and license conditions
have been met. For practical purposes, the NRC has adopted the maximum permissible
concentrations developed by the National Council on Radiation Protection and Measurements
(NCRP) to relate effluent concentrations to exposure.
1-68
-------
Li 1981, the NRC issued a policy statement on LLW volume reduction which encourages
licensees to minimize the volume of LLW generated and to use volume reduction techniques,
such as incineration, as a means of reducing the amount shipped for disposal by burial. The
policy statement clearly signaled the NRC's intent to license, on an expeditious basis,
incineration for volume reduction.
The NRC adjusts the review and approval process for applications, dependent on whether the
incinerator is to be used by an institution to reduce its own waste volume, by a commercial
entity to process waste generated by other institutions, or by a nuclear power reactor site.
Applications for institutional incinerators are reviewed by the licensing groups in the Regional
Offices. The criteria for approval are described in Appendix 1. About 70 NRC institutional
material licensees have been authorized to operate LLW incinerators for volume reduction of
their own waste as of December 1989. Approximately 50 were authorized by the Agreement
States as of May 1988.
Applications for commercial incinerators are normally submitted to the appropriate NRC
Regional Office. The information to be provided is the same as outlined for institutional
incinerators, although additional information may be requested as appropriate to assess the
potential impact on public health and safety and the environment.
Licensing of an incinerator at a nuclear power plant can follow one of several paths. The
incinerator vendor can submit a topical safety report to the NRC Office of Nuclear Reactor
Regulation (NRR) for review. The topical report contains the process description, equipment
description, design basis and process parameters, equipment arrangement, sampling/monitoring
equipment description, quality assurance plan description, a discussion of applicable Federal
regulations, and estimated releases for the incinerator. Topical
reports judged by NRR as acceptable may then be referenced in future license applications for
light water reactors. At such time, NRR would perform only a site-specific review of the
1-69
-------
process control program, effluents, monitoring systems, accident analysis, fire protection,
operational procedures, and occupational exposures.
Authorization to operate an incinerator at a nuclear power reactor can be granted as an
amendment to the existing reactor license under 10 CFR 50.59 and 50.92 if the proposed
activities or facility modifications could result in a change in technical specifications or reveal
an unreviewed safety question. The NRC defines an unreviewed safety question as:
1) if the probability of occurrence or the consequences of an accident or equipment
malfunction important to safety issues previously evaluated in the safety analysis
report is increased,
2) if there exists the possibility for an accident or malfunction of a different type
than any previously evaluated in the safety analysis report, or
3) if the margin of safety as defined in the basis for any technical specification is
reduced.
Typically, the NRC would impose additional operational requirements in the plant's technical
specifications. For example, if it were proposed to burn contaminated oils, the plant's
radiological effluent technical specifications would impose limits on the associated airborne
radioactive releases. Recent license amendments have typically limited offsite doses to 0.1
percent of the limits specified in Appendix I to 10 CFR 50, which limit whole-body doses to 5
mrem/yr and 15 mrem/yr to any organ (NRC86, NRC88).
In the case of a nuclear power reactor still under construction, the proposed incineration of
radioactive waste would be addressed in the Final Safety Analysis Report. This approach would
also be used for other types of nuclear facilities licensed under 10 CFR Parts 30, 40, and 70.
In such instances, the licensee would be required to present a report, outlined in Appendix 2,
addressing a number of related safety topics. The licensee would also be
required to submit an environmental report describing the potential impacts associated with the
proposed incinerator.
1-70
-------
The nuclear power plant applicant would also have to demonstrate that the disposal of ash and
waste products would be integrated in the existing radioactive waste management program.
More specifically, it must be shown that the waste thus generated will meet the requirements of
10 CFR 61, titled Management and Disposal of Low-Level Wastes by Shallow Land Burial.
These regulations require waste generators to characterize waste forms and characteristics, as
given in Part 60.56, and segregate such waste according to their classification (A, B, or C) as
specified in Part 60.55. Finally, the shipment of this waste must comply with the requirements
stipulated in 10 CFR 20.311 addressing transfer for disposal and shipping manifests, and the
waste generator must meet any other requirements imposed by the low-level radioactive waste
disposal site. The disposal sites operate under licenses, issued by their respective Agreement
State, which impose site-specific requirements. These requirements are also imposed on waste
generators that ship waste to these facilities.
1-6.2 Resource Conservation and Recovery Act (RCRAVRequirements
All incinerator operations involving the processing of hazardous waste (including mixed waste)
must have a RCRA permit, approved by EPA or an authorized State, to operate within the law.
EPA regulations in 40 CFR 270 indicate the minimum information to be provided by a facility
in order to obtain a permit. Individual States may impose additional or more stringent
requirements. RCRA permit applications are submitted in two sections, Part A and Part B.
Part A provides general information about the facility, including its location, owner, principal
products and processes, hazardous waste handled, and all permits and construction approvals
received or applied for under other programs. Part B must provide more detailed information
about the location and operation of the facility. The application must indicate compliance with
the regulations of 40 CFR 264 aimed at protecting the public health and environment. The
following specific information must be contained in Part B:
a. chemical and physical analyses of the waste to be handled at the facility;
b. a description of security procedures;
1-71
-------
c. a description of procedures, structures, or equipment designed to prevent hazards,
run-off and contamination of water supplies, and undue exposure of personnel to
hazardous waste; and to mitigate the effects of equipment failure or power outages;
d. facility location information including whether the facility is located in a seismically
active area or 100 year floodplain, both of which require additional detailed
evaluation;
e. an outline of the personnel training program;
f. a copy of the facility's insurance policy or other comparable documentation;
g. a topographic map showing, among other things, the legal boundaries of the facility,
surrounding land uses, access control (gates, fences), barriers for drainage or flood
control, and location of operational units within the site;
h. assurances of financial responsibility in the event of damages incurred during or as
a result of operations and for closure;
i. a trial burn plan or comparable information, as outlined in 40 CFR 270.19(C).
The trial burn is required before a permit is granted. Its purpose is to provide evidence that the
incinerator meets the RCRA performance and operating standards (ASM88).
1.6.3 State Regulations
The regulation of air emissions from radioactive and mixed waste incinerators may also be
governed by the State in which the incinerator is located. The 29 NRC agreement States
mentioned in Section 1.5.1, are bound by formal agreements to adopt requirements, applicable
to certain classes of licensees,
that are consistent with and serve in Ueu of NRC regulations. Included in such regulations are
concentration limits for release of effluents, by radionuclide, to unrestricted areas. These
regulations would apply to commercial incinerators or incinerators operated by hospitals, clinics,
or other research and industrial facilities. Federal facilities, such as the DOE incinerators, are
exempted from these regulations. The 29 Agreement States are listed below.
1-72
-------
Alabama
Arizona
Arkansas
California
Colorado
Florida
Georgia
Idaho
Illinois
Iowa
Kansas
Kentucky
Louisiana
Maryland
Mississippi
Nebraska
New Hampshire
New Mexico
New York
Nevada
North Carolina
North Dakota
Oregon
Rhode Island
South Carolina
Texas
Tennessee
Utah
Washington
The State of Illinois, as one example of an NRC Agreement State, has developed and adopted
statutes and regulations (32 Illinois Administrative Code, Chapter II) which cover, among other
activities, the licensing and operation of radioactive waste incinerators. Part 340 of the
regulations, which is a parallel to the NRC's Title 10 Part 20 regulations, provides "Standards
for Protection Against Radiation." Within Part 340, Section 340.3050 states that "No licensee
or registrant shall incinerate radioactive material for the purpose of disposal or preparation for
disposal except as specifically approved by the Department pursuant to Sections 340.1060 and
340.3020." Section 340.1060 addresses concentrations of radioactivity in effluents to unrestricted
areas. Concentration limits by radionuclide are provided in Appendix A, Table II, of Part 340.
Section 340.3020 addresses the method of obtaining approval of proposed disposal procedures.
Copies of these regulations are provided as Appendix 3.
It is important to note that agreement state regulations governing air emissions apply in addition
to EPA NESHAPS regulations. In Tennessee, for example, the commercial SEG incinerator
holds a materials license from the State, and is thus subject to Tennessee's radiation protection
regulations, which are equivalent to the NRC Part 20 regulations. It is also subject to the EPA
NESHAPS regulations for radionuclides. The same situation applies to the DSSI incinerator in
Kingston, Tennessee. However, radioactive air emissions from the DOE Oak Ridge TSCA
incinerator are regulated solely by the EPA NESHAPS requirements. While authority for
implementation of EPA regulations can also be delegated to states, Tennessee does not have
plans at present to seek delegation of authority from EPA for radionuclide NESHAPS
1-73
-------
regulations. Tennessee does have permit authority for nonradioactive air emissions from the
TSCA incinerator.
1-74
-------
Chapter 1 References
ANF90
ASM88
BAR_
BUH89
CAR_
CRC84
DOE89
DOE89a
DOE89b
DOE90
DUK85
DUK90
EGG80
Advanced Nuclear Fuels Corporation, Richland, WA, correspondence to U.S. EPA,
dated August 14, 1990, ANF file reference No. CWM:90:118.
Hazardous Waste Incineration, A Resource Document, American Society of
Mechanical Engineers, ASME Research Committee on Industrial and Municipal
Wastes, January 1988.
Barton R.G. et al. Analysis of the Fate of Toxic Metals in Waste Incinerators,
Energy Environmental Research Corporation and Environmental Protection Agency.'
Thomas Buhl; "Assessment of Radiation Doses and Resulting Health Risks From
the Controlled-Air Incinerator," Los Alamos National Laboratory, July 1989.
Cargo, C.H.; PREPP Criticality Control, EG&G Idaho, Inc.
Conference of Radiation Control Program Directors: CRCPD Survev
DOE/ID/12377, 1984, Frankfort, KY. Y>
Department of Energy; Integrated Data Base for 1989: Spent Fuel and Radioactive
Waste Inventories, Projections, and Characteristics, DOE/RW-0006 Rev 5
November 1989. -.''•'
Department of Energy; Air Quality Permit Application for the Proposed Low-Level
Waste/Mixed Waste Incinerator, Technical Area 50, Building 37 Los Alamos
National Laboratory, Los Alamos, NM, February 1989.
Department of Energy; Environmental Restoration Waste Management Five-Year-
Plan, DOE/S-0070, December 1989.
Department of Energy; Final Supplement Environmental Impact Statement Waste
Isolation Pilot Plant, DOE/EIS-0026-FS, (13 volumes) January 1990.
Duke Power Company filing; "Oconee Nuclear Station Radioactive Waste Volume
Reduction Incinerator," Letter to Harold R. Denton, NRC, from Hal B Tucker
Duke Power, June 10, 1985.
Personal communication between S. R. Phelps of S. Cohen & Associates, Inc., and
David Vaught of Duke Power Company, April 6, 1990.
Interim Report: Low-Level Waste, Institutional Waste Incinerator Program,
EG&G, Idaho National Engineering Laboratory, EGG-WM-5116, April 1980.
1-75
-------
EGG82 Radioactive Waste Incineration at Purdue University, EG&G, Inc. Idaho National
Engineering Laboratory, DOE/LLW-12T, November 1982.
EGG88 Informal Report: Low-Level and Mixed Waste Incinerator Survey Report, EG&G,
Inc. Idaho National Engineering Laboratory, EGG-LLW-8269, October 1988.
EPA87 U.S. Environmental Protection Agency; Mixed Energy Waste Study (MEWS),
Office of Solid Waste and Emergency Response, Washington, DC, March 1987.
EPA89 U.S. Environmental Protection Agency; Draft Environmental Impact Statement for
40 CFR 191: Environmental Standards for Management and Disposal of Spent
Nuclear Fuel, High-Level and Transuranic Radioactive Wastes, September 1989.
EPA90 U.S. Environmental Protection Agency; Hazardous Waste Management System;
Identification and Listing of Hazardous Waste; Toxicity; Characteristics Revisions;
Final Rule, Fed. Reg. Vol. 55, No. 61, 11798, March 29, 1990.
ERD76 Energy Research and Development Administration; Nuclear Cleaning Handbook,
ERDA 76-21, Oak Ridge National Laboratory, October 1979 reprint.
ESC89 Eschenbach, R.C., et al., Process Description and Initial Test Results with the
Plasma Centrifugal Reactor, Forum on Innovative Hazardous Waste Treatment
Technologies: Domestic and International; June 19-22, 1989, Atlanta, GA.
FL089 Flowers, R. H. and Owen, R. G.; "Review of the packaging of LLW and ILW for
disposal," Radioactive Waste Management 2, BNES, London, 1989.
FRA89 Francis, C.J., Starr, T.M., The ANF LLW Incinerator Design and Startup,
Advanced Nuclear Fuels Corporation, Richland, WA, April 1989.
GAL_ Gale, L.G.; PREPP Incinerator Partitioning Studies, EG&G Idaho, Inc. and IT
Corporation.
HET90 Technical correspondence from Mr. Frank Hetzler (Studsvik Nuclear) to Mr. Larry
Coe (SC&A, Inc.), dated February 5, 1990.
HUT90 Telephone communication between Mr. David Hutchins, LANL, and Mr. Jean-
Claude F. Dehmel, , Inc., April 24, 1990.
IAE89 International Atomic Energy Agency; Treatment of Off-Gas from Radioactive Waste
Incinerators, Technical Reports Series No. 302, Vienna, 1989.
INEL88a The Idaho National Engineering Laboratory Site Environmental Report for Calendar
Year 1988, DOE/ID-12082(88), June 1989.
1-76
-------
INEL88b Environmental, Safety and Health, Office of Environmental Audit, Environmental
Survey, Preliminary Report, Idaho National Engineering Laboratory
DOE/EH/OEV-22-P, September 1988. ^'
INEL88b Environmental, Safety and Health, Office of Environmental Audit, Environmental
LAN83
LUK90
NRC83
NRC86
NRC88
PUC90
RET90
RFP82
RIN
TRI89
Landolt, R.R.; Evaluation of a Small, Inexpensive Incinerator for Institutional
Radioactive Waste, Health Physics, Vol. 44, No.6, pp. 671-675, June 1983
Mr. Thomas Lukow, DOE/RFP submittal to U.S. EPA, dated Oct. 29, 1990
Nuclear Regulatory Commission; Incineration of a Typical LWR Combustible Waste
and Analysis of the Resulting Ash, NUREG/CR-3087, Battelle Pacific Northwest
Labs, May 1983.
Nuclear Regulatory Commission; Amendments No. 42 and 53 to Operating Licenses
No. NPF-15, Radioactive Effluents, San Onofre Nuclear Generating Station, Units
2 and 3, August 20, 1986.
Nuclear Regulatory Commission; Amendments No. 115 and 101 to Operating
Licenses No. DPR-58 and DPR-74, Radioactive Effluents, Donald C. Cook Nuclear
Power Plant Units 1 and 2, May 19, 1988.
Mr. John Puckett, DOE/LANL submittal to U.S. EPA, dated Nov. 9, 1990.
Correspondence, Matt Mede, RETECH, Inc. to Jean-Claude F. Dehmel SC&A
Inc., September 21, 1990. '
Rocky Flats Plant Fluidized Bed Incinerator, RFP-3249, Rockwell International
Golden CO, March 8, 1982. '
Ringel, H. and Rachwalsky, U.; Laboratory Experiments on the Volatilization of
Heavy Metals during Waste Incineration, Kernforschungsanlage Julich GmbH
Germany. '
Trichon, M., Feldman, J.; Designing an Incinerator to Handle Mixed Waste Roy
F. Weston, Inc., paper presented at the 1989 International Conference on
Incineration of Hazardous, Radioactive and Mixed Wastes
1-77
-------
UNS82 United Nations Scientific Committee; Ionizing Radiation: Sources and Biological
Effects, 1982 Report to the General Assembly, Annex C, Technologically Modified
Exposures to Natural Radiation, 1982.
WM85 Swearing, F.L.; Waste Management 1985, Incineration of Microspheres.
1-78
-------
2. Technologies for Controlling Incinerator Processes
and Radionuclide Emissions
2.1 PROCESS CONTROL TECHNOLOGY
Process controls maintain the incineration system within safe operating limits. This is
accomplished by a series of control loops that use feedback control, feedforward control, or a
combination, to manipulate the process variables to achieve safe and smooth operation.
For feedback control, information about the controlled variable is fed back to control a process
variable. A typical feedback control loop requires a sensor to measure the variable, a
transmitter to provide a feedback mechanism, and a controller to compare the measured value
with the setpoint value and send a signal to a control element or an actuating device to effect a
direct or indirect change in the controlled variable. Depending on whether the controller is an
operator or an instrument, the control loop can be either manual or automatic. In automatic
systems, the controller can exert control through one or more of the following modes:
On/off: The controlling element is either on or off.
Proportional: The signal to the control element and the resulting response are
proportional to the measured deviation of the controlled variable from the setpoint.
Proportional plus Integral: Used to compensate for the inability of proportional control
to achieve the setpoint value. The integral mode applies a signal to the control element
that is proportional to the integral of the deviation. This causes the controller output to
change as long as a deviation exists.
Derivative Action: The controller anticipates where the process is going by measuring
the rate of change of the deviation from the setpoint and applies a control action
proportional to the rate of change to stop the change.
2-1
-------
For feedforward control, a variable which affects the controlled variable is measured and then
a signal is sent to compensate for the change without waiting for the controlled variable value
to change. Feedforward control improves the ability to respond to process disturbances;
however, since it requires solution of an equation or process model, a combination of feedback
and feedforward control is more desirable.
Selection of the type of control depends on the requirements of the particular system and the
requirements of each control loop. A controlled variable that changes slowly or remains fairly
constant could be controlled manually. Process water flowrate to a packed bed scrubber is an
example of this kind of variable. A controlled variable that changes frequently or rapidly
requires automatic control. Typical examples for incinerators are combustion air flows,
supplemental fuel flows, and incinerator pressure.
The primary control loops for an incinerator are: waste, fuel, air and water flowrates;
temperatures in different parts of the system; pressures in different parts of the system; excess
oxygen concentrations; pH in the process, water system; and levels in process water storage
tanks. Incinerator control functions are summarized in Table 2-1 and described in Appendix 4.
2.2 PROCESS MONITORING TECHNOLOGY
Monitoring systems complement the control systems to ensure safe operation and prevent
emissions of toxic and radioactive materials. Control systems are designed to keep the process
variables within safe operating limits; monitoring systems take over whenever the process
variables approach the operating limits. A properly designed monitoring system keeps the
process variables within safe operating limits with a minimum disturbance to the system. The
three levels of automatic monitoring are: alarms, feed cutoffs, and equipment shutdowns.
2-2
-------
Table 2-1. Incineration System Control Functions
System
Feed System
Variable
Controlled
Solid Feedrate
Sensor
Weigh Belt
Weigh Scale
Control Element
Screw Speed
Scale Weight Setting
Constraints
Maximum Feedrate,
Primary Chamber Temp
lerature, and
Combustion
Controls
Kiln
Liquid Feedrate
Kiln
Temperature
Excess Oxygen
Chamber
Pressure
sec'
Temperature
SCC Excess
Oxygen
Flowmeter
Control Valve
Thermocouple Fuel Control Valve
Water Control Valve
Oxygen Meter FD Fan Damper
Fuel Meter FD Fan Speed
Air Flow Meter
Pressure
Flowmeter
ID Fan Damper
Fuel Control Valve
Oxygen Meter FD Fan Damper
Fuel Meter FD Fan Speed
Air Flow Meter
High Gas Velocity (Secondary Chamber
Residence Time)
Maximum Feedrate, Maximum Liquid
Waste Pressure
High Temperature, Low Temperature
Low Oxygen
High Carbon Monoxide
High Pressure (Low Draft)
High Temperature, Low Temperature,
High Gas Velocity
Low Oxygen
High Carbon Monoxide
-------
Table 2-1. (Continued) - Page 2
System
Variable
Controlled
Sensor
Control Element
Constraints
Controlled Air
Incinerator
Fluidized Bed
Air Pollution
Control
Quench System
Primary
Chamber
Temperature
sec
Temperature
Temperature
Excess Oxygen
Temperature
PH
Level
Total Dissolved
Solids
Thermocouple Air Damper
Thermocouple Air Damper
Thermocouple
Fuel Control Valve
Water Control Valve
Air Damper
Oxygen Meter Air Damper
Thermocouple Control ValveHigh/Low
Temperature
Minimum Process Water
Glass
Electrode
Pressure
Conductivity
Neutralizing Liquid
Control Valve
Control Valve
Slowdown Valve
High Temperature, Low Temperature
High Temperature, Low Temperature
High Temperature, Low Temperature
Minimum Oxygen, High Carbon
Monoxide, Minimum Airflow
High/Low pH
High/Low I^evel
Maximum Dissolved Solids Content
-------
Table 2-1. (Continued) - Page 3
System
Variable
Controlled
Sensor
Control Element
Constraints
Acid Gas
Removal
Packed Scrubber
Acid Gas
Removal
Spray Dryer
Venturi Scrubber
Liquid to Gas
Ratio
Scrubber Water
Flowrate
pH
Liquid to gas
Ratio
Exit
Temperature
Liquid to Gas
Ratio
Water Flowrate
Flowmeter
Flowmeter
Glass
Electrode
Water Control Valve
Water Control Valve
Neutralizing Liquid
Control Valve
Flowmeter Spray Control Valve
Thermocouple Spray Control Valve
See Packed
Scrubber
See Packed
Scrubber
Minimum Water Flowrate
Minimum Flowrate
High/low pH
Minimum Flowrate
Maximum Temperature
-------
Table 2-1. (Continued) - Page 4
System
Variable
Controlled
Sensor
Control Element
Constraints
KJ
Particulate
Removal
Venturi Scrubber
Fabric Filter
pH
Water Flowrate
Pressure Drop
Pressure Drop
Wet Electrostatic DC Voltage
Precipitator
See Packed
Scrubber
See Packed
Scrubber
Pressure
Pressure
Pinch Valve or
Recirculation Valve
Air Dampers or
Compressed air Valves
Sparking Rate Sparking Rate Controller
High Vacuum, High Pressure Drop,
High Temperature
High Pressure Drop,
High/Low Temperature
Corona Discharge
-------
Alarms warn the operator that a monitored variable is approaching an operating limit.
This warning gives the operator time to check the problem and take corrective action.
Any variable that causes a feed cutoff or equipment shutdown should be alarmed before
its value reaches the limit for feed cutoff or equipment shutdown. Occurrence of
feedcutoffs and equipment shutdowns are also alarmed.
Feed cutoffs are activated when a variable goes out of range in a manner that may
produce emissions from the incinerator. Feed cutoffs do not shut down other parts of
the system other than the feed system. When the affected variable returns to the
operating limits, waste material feed is allowed to resume.
Equipment shutdowns are activated when a variable goes out of range in a manner that
may create a dangerous operating condition or cause damage to the equipment. Any
action requiring an equipment shutdown also requires a feed cutoff. Since an equipment
shutdown is the last line of defense, this action causes maximum disturbance of the
process. Shutdown systems should be hard-wired and independent of other controls.
Separate sensors and transmitters should be provided for temperature, pressure, flow,
etc. Signals requiring shutdowns should not be processed through the algorithm of a
programmable controller.
All safety shutdowns and feed cutoffs should require a manual reset by the operator after the
condition has been corrected, and the control console should be provided with a first-out feature
that identifies the primary cause of the alarm, cutoff, or shutdown. All hardware should be
designed to fail in a safe direction. For example, a fuel valve should be designed to fail closed.
Safety shutdown systems require regular checking to ensure operability. A check should include
inspection of the safety circuits and mechanisms to make sure that there has been no tampering,
jumpering, clogging, galling, wearing, corroding, or other irregularity. Instruments should be
calibrated on a regular schedule. Relays and valves should be actuated on a regular basis to
prevent hangups when they are actually needed. Emergency vent valves are particularly prone
to sticking if they are not exercised.
2-7
-------
Incinerator monitoring sub-systems are summarized in Table 2-2 and described in Appendix 5.
2.3 EMISSION CONTROL TECHNOLOGY
Although the bulk of the radionuclides present in the waste will remain in the solid residue from
the combustion chamber, some will be present in the incinerator off-gas. Some will Combine
with the carry-over particulates, others may volatilize from the high combustion temperatures
into off-gas vapor. The off-gas may also contain noxious and/or corrosive gaseous constituents
such as NO3, CO, HC1, HP, and SO2, depending on the chemical composition of the incinerated
waste. The function of the emission control system is to clean the off-gas of particulates and
radioactive, noxious, and corrosive gaseous components. The emission control system,
consisting of components for removal of particulates and gases, must be incorporated in the
incineration system to protect the environment against radiological as well as conventional
chemical hazards.
Emission control systems perform various operations such as cooling, dust removal, acid gas
removal, and hydrocarbon treatment. Each system will have a unique combination of cleaning
equipment to fit the performance requirements of the incinerator and the waste feed. Two basic
types of emission control systems are used. Wet systems utilize cooling or scrubbing devices
to saturate the off-gas stream in intermediate steps, and then heat or dry the gas stream before
final filtration to avoid moisture condensation on the filters. Dry systems do not saturate the gas
stream, although water injection may be used for cooling. Dry emission control systems are
usually used when the PVC content of the waste feed is low, because emission of HC1 is not a
problem. A typical system may include high temperature filtration, cooling, filtration or
separation, adsorption, and high efficiency filtration. Wet emission control systems are used for
treatment of off-gas when removal of HC1, SOX NOX or HF is required. Typical systems may
include off-gas cooling, scrubbing, heating, and high efficiency filtration. The operation of both
wet and dry emission control systems results in secondary hazardous/radioactive wastes,
including filters, adsorption material, liquid scrubber solutions, and blowdowns. Some of these
2-8
-------
Table 2-2. Incinerator Monitoring Subsystems
to
System
Solid Feed
Liquid Feed
Atomizing Media
Limestone
Injection
Primary
Chamber
Variable
Monitored Trip
Shredder
Feedrate
Feedrate
Low Pressure
High Pressure
Low Temperature
Low Pressure
Feedrate or
limestone-to-feed
ratio
High Temperature X
Feed
Cutoff Alarm Records
X X
X
X
X X
X X
X X
X X
X . X X
X X
Incinerator
Type
All
All
All
All
All
All
All
Fluidized
Bed
All
Comments
Shredder must be running for proper feed
preparation
Feedrate must be monitored to satisfy
regulatory requirements
See above
Required for adequate atomization
High pressure may cause overfiiing
Required for adequate atomization for liquid
wastes that require heating
Pressure is needed for adequate atomization
May be required to ensure adequate acid gas
removal
High temperature trip consists of shutting
Low Temperature
X
X
All
equipment
Feed cutoff on low temperature is required
to ensure adequate waste destruction
-------
Table 2-2. (Continued) - Page 2
System
Variable
Monitored
Feed Incinerator
Trip Cutoff Alarm Records Type
Comments
Primary
Chamber
Burner
Loss of Draft X X All
Loss of Draft Feed Cutoff Required to
Minimize Fugitive Emissions from the
Incinerator
Fluidized Feed Cutoff Required to Ensure Adequate
Waste Destruction
Fluidized Feed Cutoff Required to Ensure Adequate
Waste Destruction
Low Oxygen XXX
Concentration or Bed
Analyzer
Malfunction
High Carbon X X X
Monoxide Bed
Concentration or
Analyzer
Malfunction
There are separate monitoring systems for the primary chamber and secondary chamber burner systems
High Fuel Pressure XX All Applied Whenever Burner Is Operating
Low Fuel Pressure X X All See Above
XX All
Low Atomizing
Pressure
Loss of Flame
X
X
All
For Fuel Oil Only
Trip Applies on System Warm-up
-------
Table 2-2. (Continued) - Page 3
System
Burner (cont'd)
Secondary
Chamber
Variable
Monitored Trip
Lack of Air Purge X
Combustion Air X
Pressure
High Temperature X
Low Temperature
Low Oxygen
Concentration or
Analyzer
Malfunction
High Carbon
Monoxide
Concentration or
Analyzer
Feed Incinerator
Cutoff Alarm Records Type
X X All
XX All
X X All
X X All
XXX Rotary
Kiln
Controlled
Air
X X Rotary
Kiln
Controlled
Air
Comments
Applies on Initial Start-up
Trips
and Afterburner
High Temperature Trip Consists of Shutting
Down Secondary Chamber Burners and
Primary Chamber Burners to Protect
Equipment
Feed Cutoff on Low Temperature Required
to Ensure Adequate Waste Destruction
Feed Cutoff Required to Ensure Adequate
Waste Destruction
Feed Cutoff Required to Ensure Adequate
Waste Destruction
Malfunction
High Gas Velocity
X X
All
Ensures Adequate Residence Time for
Waste Destruction
-------
Table 2-2. (Continued) - Page 4
Variable
System Monitored Trip
Air Pollution
Control System
Quench High Exit X
Temperature
Low Exit
Temperature
to
»— >
10 Low Coolant X
Flowrate
Venturi Scrubber Low Flue Gas
Pressure Drop
Low Scrubber
Water Flowrate
High Vacuum
Fabric Filter High Pressure Drop
Wet Electrostatic Low DC Voltage
Feed Incinerator
Cutoff Alarm Records Type
X X All
X X All
X X All
XX All
XX All
X X All
X All
X X All
Comments
Trip Required to Protect Equipment
Feed Cutoff Required to Prevent Clogging
of Baghouses or Shorting of Dry
Electrostatic Precipitators
Trip Required to Protect Equipment.
Feed Cutoff Required to Prevent Excessive
Emissions
Feed Cutoff Required to Prevent Excessive
Emissions
Required to Protect Equipment
Alarmed
Required to Prevent Excessive Emissions
Precipitator
-------
. Table 2-2. (Continued) - Page 5
to
System
Packed Scrubber
HEPA Filter
Carbon bed
General
Subsystems
ID Fan
Instrument air
Electrical
Emission
Monitors
Gases:
Carbon
Monoxide
Variable
Monitored Trip
Low Scrubber
Water Flowrate
High Pressure Drop
High Pressure Drop
Loss of Vacuum X
Low Instrument Air
Pressure
Loss of Power X
Feed Incinerator
Cutoff Alarm Records Type Comments
X X All Feed Cutoff Required to Prevent Excessive
Emissions
x All Filter Requires Changeout
X All Replacement Required
X X All Loss of Vacuum Trips All Burners and
Activates the Emergency Vent
X X All Loss of Instrument Air Causes a
Trip.
X X All Loss of Power Causes a General
General
Trip.
X X X All Regulatory Requirement and Efficiency
Carbon Dioxide
X
All
Calculation
Used for Efficiency Calculation
-------
Table 2-2. (Continued) - Page 6
Variable
System Monitored
Oxygen
Total
Hydrocarbons
Nitrogen Oxides
CulfiiT TlifwiHi=»
Feed
Trip Cutoff Alarm Records
XXX
X
X
X
Incinerator
Type
All
All
All
All
Comments
Regulatory Requirement
I
t—*
*«.
-------
wastes may be processed by incineration. Others may have to be disposed of separately, and
possibly immobilized before disposal.
As an example of emission control, the system used on the controlled air incinerator (CAI) at
Los Alamos National Laboratory consists of an aqueous scrubbing system followed by a dry off-
gas cleaning system. The scrubbing system includes a quench tower, high energy venturi
scrubber, packed-column absorber tower, condenser, and a process system for recycled liquid.
The downstream dry off-gas system includes a superheater, roughing or prefilter, H[PA filters,
and an adsorption tower.
2.3.1 Removal of Particulates
Basically, particulates are removed by filtration, separation, and scrubbing techniques.
Descriptions of major components follow:
2.3.1.1 Filtration
2.3.1.1.1 High Temperature Filters. High Temperature Filters operate in the 1100-2000°F
temperature range. At these temperatures, the filter elements are red hot contact surfaces on
which unburned particles in the flue gas are incinerated. The ash falls off the filter elements
during combustion and collects in the bottom of the filter housing.
Ceramic candle filters, made of silicon carbide, can be used at temperatures up to 2000°F. The
cylindrical filter elements are suspended from support plates inside a refractory lined housing.
When the operational pressure drop is exceeded, the candles are blown back by compressed air
to clean the filters.
Ceramic fiber filters, made of plugs in fine-meshed expanded metal, operate at around 1300°F.
A filter is built up of several plugs assembled vertically. The plugs are lined with a deposit of
asbestos fibers. When the filter becomes clogged, it is cleaned and regenerated with new
2-15
-------
asbestos. Because of the asbestos fibers used, these filters may not be suitable for use in the
United States.
2.3.1.1.2 Baqhouse Filters. Baghouse Filters consist of permeable bags made of teflon felt or
glass fiber which can operate at temperatures up to 500°F. They are sometimes used as
prefilters to reduce the clogging rate of HEPA filters.
Filter fabrics are usually woven with relatively large openings in excess of 50 microns in
diameter. However, smaller particles are captured since filtration employs the combined effects
of impact, diffusion, gravitational attraction, and electrostatic forces generated by interparticle
friction. The dust layer itself also acts as a filter medium. When the filter surface resistance
reaches its capacity due to dust build-up, it must be cleaned. Some cleaning mechanisms
physically shake a bag section, and the particles drop to the bottom by gravity. Compressed air
is also used to inflate the bag and loosen the dust cake, which falls to the bottom.
2.3.1.1.3 High Efficiency Particulate Air Filters. High Efficiency Particulate Air Filters
(HEPA) are constructed of glass fiber mat which produces a particle removal efficiency of at
least 99.97 percent for 0.3 micron particles of dioctylphthalate (DOP) aerosol. These filters are
used for final cleanup of particulates, and will not remove gases. Nuclear grade HEPA filters
must meet requirements specified by the Institute of Environmental Sciences (IES)
"Recommended Tentative Practice for Testing and Certification of HEPA Filters, IES RP-CC-
001-83-T."
HEPA filter assemblies are made up of individual cells that are typically 24 inches high,
24 inches wide, and 11 1/2 inches deep. The filter media consists of nonwoven corrugated glass
fiber (typically boron silicate microfiber) that is folded into pleats, with a corrugated separator
between each pleat if the media is fiat. Adhesive is used to seal the media to a wood or metal
frame. The cell, which may be covered with a metal cloth faceguard for protection, is mounted
in the holding frame with a gasket or fluid seal to prevent the possibility of bypassing unfiltered
gas around the filter. With normal adhesives, HEPA filters can operate up to 250°F. With
2-16
-------
silicone adhesives, temperatures up to 500°F may be tolerated. For high temperatures up to
1000°F, glass packing mechanical seals may be used between the cells and the frame. HEPA
filter media is treated with a water-resistant binder and will tolerate some humidity, however,
excess moisture can plug the filter and result in failure by overpressure. Wood framed filters
are unsuitable for systems with high moisture content since they will expand and warp when wet.
Since HEPA filters are an essential part of an emissions control system, particularly for
radionuclides, they are monitored for pressure drop to ensure their integrity. HEPA filters are
designed for a maximum clean pressure drop of 1 inch HzO. A pressure drop of 2 inches HzO
indicates that the filter is dirty and has reached the end of its service life. The service life of
a HEPA filter depends on the amount of particulates in the off-gas, and can be extended by
removing larger particulates in upstream emission control equipment. Other operating
parameters that indicate possible HEPA filter failure include high temperature and pressure. The
sealant on a HEPA filter subjected to higher- than-design temperature for an extended period of
time will degrade. An operating pressure higher than the HEPA's design pressure may rupture
the filter media. A rupture would be indicated by a decrease in the normal filter pressure drop.
Nuclear grade HEPA filters must be tested while encapsulated for resistance to airflow and
penetration in accordance with Mil-Std-282, DOP Smoke Penetration and Air Resistance of
Filters, at the nominal rated capacity listed in Mil-F-51068 and at 20 percent of that capacity for
penetration. The Mil-Std-282 procedure is known as the "hot" DOP test because thermally
generated dioctylphthalate (DOP) particles are used to challenge the filter. The Q 107
penetrometer test apparatus must be used to ensure that the DOP particles are homogeneous in
size (0.3 micron) in order to form a monodispersed aerosol.
The HEPA filter assembly to be tested is encapsulated in the test box to ensure that any leakage
through the gasket or frame will contribute to the overall penetration. The overall penetration
through the filter can not exceed 0.03 percent (100 percent-0.03 percent = 99.97 percent
efficiency). This efficiency represents the average efficiency of this particular filter. There may
be minute areas of the filter with greater penetration (gasket, frame, or element) but these are
2-17
-------
diluted by the greater volume of clean air passing through the filter. The 20 percent flow test
helps detect major pinhole leaks that may have been missed in the full flow test. At 20 percent
flow a pinhole leak shows up approximately 25 times greater in proportion to total flow,
compared to 100 percent flow. This is because the constriction of air through the pinhole is a
function of the square of the velocity.
Even though all nuclear grade HEPA filters are factory tested, the Department of Energy retests
each filter before shipment to the using facility. When the HEPA filters are installed, they are
tested in-place per ANSI N 510 (standard for testing nuclear air cleaning systems). This in-place
field test, called the "cold" DOP test, is done with a polydisperse DOP aerosol that has a
particle size range from 0.1 to 3 microns. It is used to reveal the presence of any leaks in the
system that may have resulted from shipping the HEPAs or from installation. It is not
considered an efficiency test. The cold DOP test requires the challenge aerosol to be introduced
into the airstream at a distance sufficiently upstream of the HEPA assembly to ensure proper
mixing.
New types of HEPA filters are currently being developed to circumvent some of the inherent
limitation of existing designs and materials. New HEPA filter designs rely on the use of woven
glass-fiber cloth and aluminum separators. These modifications make the filters less susceptible
to structural failure and blow-out, and permit the filters to be used at higher temperatures. Such
filters are being manufactured in England and Germany. German licensing agencies have
authorized their use at a few facilities and are now considering their installation at all new
nuclear facilities (Bergman, Ruedinger-1986, Ruedinger-1988).
In the United States, Lawrence Livermore National Laboratory (LLNL), in cooperation with the
industry, has developed a sintered stainless-steel HEPA filter (Bergman-1990a). The steel
filtration media is made of sintered powder and sintered fibers. Powder grains and fibers are
about 5 urn in overall dimensions. The media is held in place by a steel mesh which sandwiches
the powder grains or fibers in rigid pleats. The stainless-steel HEPA filter is less susceptible
to structural failures and can withstand much higher operating temperatures than its glass-fiber
2-18
-------
counterpart. One of the limitations of stainless-steel filters is that they have characteristically
high pressure drops. For a given flow rate, the stainless-steel HEPA filter would have to be
larger. Tests conducted by LLNL indicate that for a given flow rate and particle penetration,
the stainless-steel HEPA filter would need about 3 times the filtration area of a glass-fiber HEPA
filter. This limitation implies that existing off-gas systems could not be readily retrofitted since
new filter housings would have to be installed to accommodate the much larger steel filters.
Finally, LLNL has indicated that currently, such filters are expensive to make. It has been
estimated that a filter rated at 1,000 CFM with a 1-inch pressure drop would cost about
$200,000, compared to about $200 for a conventional glass-fiber HEPA filter (Bergman-1990b).
In addition to incineration emissions control, HEPA filters are used in virtually all nuclear
facilities for air control. As a result, used HEPA filters are one of the largest single waste
types. Used HEPA filters constitute a high volume, low density waste composed of wood or
metal frames, organic binders and gaskets, glass fiber media, and hazardous and radioactive
contaminants. HEPA filters used in low-level radioactive service can be disposed of by
incineration. Pacific Northwest Laboratory (PNL) conducted tests on incineration of HEPA
filters with simulated transuranic waste. The tests were performed on three incinerators;
electrically heated controlled air, gas heated controlled air, and rotary kiln. The tests confirmed
that all three incinerators could effectively process HEPA filters.
2.3.1.2 Separation
2.3.1.2.1 Cyclones. Cyclones remove particles greater than 10 microns from the gas stream
and are normally used before other control devices such as an electrostatic precipitator or
baghouse. Cyclones are often used downstream of the primary combustion chamber of a rotary
kiln incinerator.
A cyclone removes particles by inertia. The gas entering the cyclone forms a vortex which
reverses direction and forms a second vortex leaving the cyclone. Due to inertia, particulate
2-19
-------
matter moves to the outside wall and drops out the bottom while the gas exits the top of the
cyclone. The temperature range for cyclones is 400-1800°F (refractory lined).
2.3.1.2.2 Electrostatic Precipitators. Electrostatic Precipitators (ESPs) are very efficient at
collecting small-size particulate material suspended in a gas stream. The gas stream passes
through an electric field which induces an electric charge in the particulate matter. The charged
particles collect on a grounded surface, or collector. Particulate matter is periodically removed
from the collecting plates by an internal or external rapping system.
The resistivity of the particulate matter affects ESP design and performance. High resistivity
particles do not give up their electric charge to the collecting electrode and build up on the
collector. Low resistivity particles readily relinquish their charge to the collector, assume the
collector charge, and are repelled back into the gas stream. A particle with the correct
resistivity gives up part of its charge to the collector. The rate at which the charge dissipates
increases as the dust layer builds on the collector. When the weight of the collected particles
exceeds the electrostatic force available to hold the layer, it falls off or is knocked off by the
rapping system.
Since material resistivity varies with temperature, the use of an ESP requires an operating range
where the resistivity is within acceptable limits. The temperature limit for ESPs is usually 300
to 350°F. The off-gas velocity also affects ESP operation.
2.3.1.2.3 Wet Electrostatic Precipitators. Wet Electrostatic Precipitators (WESPs) differ from
ESPs in the method of cleaning the built-up particles from the collector plate. WESPs use water
sprays to saturate or supersaturate the incoming gas stream. The electric field charges the liquid
droplets. The liquid droplets charge, collect, and wash away the particulates from the gas
stream. Resistivity does not restrict WESP operation.
2.3.1.2.4 Ionizing Precipitators. Ionizing Precipitators consist of an ionizer followed by a
packed bed. High voltage ionizer elements charge particulates in the gas stream as they enter
2-20
-------
the unit. The ionizer elements are continuously water washed to prevent particulate build-up.
The charged particles are removed in the packed bed. Particles above 3 microns are removed
by striking the packing; smaller particles are removed by image-force attraction. The packed
bed is continuously washed with water to remove the collected particles.
2.3.1.3 Scrubbing. Off-gas may contain NOX, SOX, HC1, HF, and radionuclides in the form
of aerosols. These gases and particulates can be removed by scrubbing. The offgas is scrubbed
using demineralized water or caustic solution which is circulated by the energy of the off-gas
or an external pump. There are two types of scrubbers. The first, which includes the venturi
scrubber and variable orifice scrubber, removes particulates. These scrubbers will also
neutralize acid gases somewhat, but are not totally effective for gas removal. As a result they
are usually followed by packed-bed scrubbers. The second, which includes the packed-bed
scrubber, impingement tray scrubber, and spray dryer, removes acid gases. These devices will
remove acid gases but are not very efficient at removing particulates from the off-gas stream.
Scrubber effectiveness is related to the pressure drop across the scrubber. Increasing the
pressure drop causes greater turbulence and mixing which results in a more effective scrubbing
action. Scrubbers operate on the principles of interception, gravity, impingement, and
contraction/expansion. Interception occurs when a solid particle collides with a liquid particle.
Gravity causes a particle passing near an obstacle to settle on it. When an obstacle is placed in
a gas stream, the gas will flow around it while the particles will tend to impinge on it.
Contraction in a gas stream produces condensation and turbulence which results in contact
between solid particles and liquid droplets. When the gas stream is expanded, the particle laden
droplets maintain direction while the gas can be diverted and separated.
A wet scrubbing system generates radioactive scrub liquor waste. Scrubbing solution is usually
treated in a subsystem and recycled back to the scrubber. A typical subsystem consists of a heat
exchanger to cool the scrub liquid before entering a circulation tank where it is neutralized with
caustic. From the circulation tank it is pumped to a hydrocyclone to remove particulates and
2-21
-------
then recycled back to the scrubber. The blowdown from the hydrocyclone is filtered to meet
industrial wastewater treatment facility requirements.
2.3.1.3.1 Venturi Scrubbers. Venturi Scrubbers are high energy (high pressure drop), high
efficiency scrubbers usually operating at pressure drops greater than 40 inches H20 for submicron
particle removal. Scrubbing liquid is injected upstream of the venturi throat into the contracted
gas stream at velocities from 200 to 600 ft/sec. The off-gas then passes into an expansion
section where separation occurs. Some scrubbers have adjustable venturi throats to maintain a
desired pressure drop when the flow varies. The venturi only conditions the off-gas, and it must
be followed by other separation equipment to remove the particulates from the gas stream.
2.3.1.3.2 Variable Orifice Scrubbers. Variable Orifice Scrubbers are similar to the venturi
scrubber except a butterfly valve is used in the gas stream to create a venturi effect. The valve
can be adjusted to maintain a fixed pressure drop as the flow changes.
2.3.2 Removal of Gases
Mechanical separation equipment is not effective for removal of volatile or semivolatile elements
and compounds. A chemical or physicochemical liquid or solid absorption reaction is necessary
to remove these constituents from the offgas.
2.3.2.1 Liquid Absorption. Liquid absorption uses water or chemical scrubbing solutions
(NaOH, Na2CO3, CaCOH)^ to react with and remove soluble constituents in the off-gas.
2.3.2.1.1 Packed Bed Scrubbers. Packed Bed Scrubbers consist of vertical towers filled with
packing material. The packing material provides a large surface area for the off-gas to contact
the scrubbing solution. The scrubbing solution (usually water, caustic, or lime slurry) trickles
down from the top of the tower through the packing. The off-gas moves up through the tower
countercurrent to the scrubbing liquid and reacts with it.
2-22
-------
2.3.2.1.2 Impingement Tray Scrubbers. Impingement Tray Scrubbers consist of perforated
baffles and target baffles in a tower. A water level is maintained above the trays. The off-gas
flows through the openings in the perforated plates, against the static water pressure, and around
the target baffles. Scrubbing is caused by the turbulent mixing resulting from the off-gas passing
through the trays.
2.3.2.1.3 Spray Dryers. Spray Dryers consist of cylindrical chambers into which a finely
atomized absorbent such as lime slurry is sprayed. The acid gas in the off-gas stream reacts
with the slurry droplets and forms particulates such as calcium chloride. These particulates are
removed in downstream equipment such as a baghouse filter or electrostatic precipitator.
2.3.2.2 Solid Adsorption. Solid adsorption results from interaction of gas molecules with
activated surfaces. Radioactive gases can be removed by carbon adsorbers, also known as high
efficiency gas adsorbers (HEGA). HEGAs use granular activated coconut shell carbon
impregnated to adsorb radioactive gases. Three types of adsorption occur: kinetic, isotopic
exchange, and complexing or chemisorption. Kinetic adsorption of a gas molecule is the
physical attraction of the molecule to the carbon granule by electrostatic forces. In isotopic
exchange, carbon is impregnated with a stable isotope which exchanges with the radioisotope.
In chemisorption, a radioactive iodine species attaches chemically to a stable impregnant that has
the ability to share electrons. A typical impregnant is triethylenediamine (TEDA) or some other
tertiary amine product. Carbon can be co-impregnated to take advantage of kinetic, isotopic
exchange, and complexing adsorption mechanisms. The type of carbon impregnation and the
residence time required in the HEGA will depend on the radionuclides to be adsorbed.
Carbon adsorbers usually consist of a number of 2-inch thick flat bed cells of charcoal, 24 inches
long and 24 inches wide. Since the adsorption efficiency of charcoal beds is adversely affected
by water vapor, they are normally preceded by condensers and heaters. Because of this, the off-
gas is normally heated above the saturation temperature. However, the temperature is kept close
to the saturation point since adsorber beds operate more efficiently at lower temperatures.
2-23
-------
Carbon adsorber systems are leak tested in place with a test gas, normally freon 11. The
penetration or bypass of the freon measured downstream of the adsorber is compared with the
upstream measurement to obtain the mechanical efficiency. The carbon is tested periodically
(per US NRC Reg. Guide 1.52) for its ability to adsorb. Sampler devices can be included in
the adsorber design. This allows samples to be removed and sent to the lab for processing
without removing the adsorber.
2.4 CAPITAL AND OPERATING AND MAINTENANCE COSTS
It is difficult to estimate incineration costs because of the many factors involved. The type of
waste to be incinerated, the location, size and type of the incinerator, and regulatory
requirements are some of the factors that affect cost. The costs associated with an incineration
system include capital or fixed costs, and operating or annual costs. Cost elements in each of
these categories are listed in Appendix 6.
The capital cost of a hazardous waste rotary kiln incineration system can vary from
approximately $1 million for a 0.5 million Btu/hr unit to over $40 million for a 100 million
Btu/hr unit. The total annual operating costs vary from $2 million for the 0.5 million Btu/hr
unit to $20 million for the 100 million Btu/hr unit.
The capital and operating cost of a radioactive/mixed waste incinerator will be greater than that
of a hazardous waste incinerator. The radioactive/mixed waste system must be designed to
minimize radiation exposure to as low as reasonably achievable (ALARA) levels. This will
necessitate design modifications such as shielding, allowances for easy access, materials of
construction that facilitate decontamination, increased monitoring, and additional emission
control equipment.
2-24
-------
2.5 OPERATIONS AND MAINTENANCE CONCERNS
Appendix 7 contains tables summarizing general operations problems and preventative
maintenance actions. Brief discussions of selected operations and maintenance concerns follow.
2.5.1 Pretreatment
Waste pretreatment is common to most incinerator systems. Accepted operations vary from
hand sorting to automated shredding of bulk materials. Feed size reduction is desirable since
the larger surface area in the reduced size permits more efficient combustion. Typical
maintenance for a pretreatment system includes annual replacement of shredder gears, and
periodic replacement of hoses, sensors, and electronics. Pretreatment considerations include the
following:
Sorting removes difficult to shred or nonincinerable materials, but is a time consuming
process requiring additional installations such as a ventilated sorting area.
Not sorting usually results in corrosive deposits at various steps in the process (fans,
pumps, etc.). PVC, which in the incineration process forms chlorides and highly
corrosive HC1 gas, is a known operational corrosion source in gas phase incineration
operations. In the absence of sorting, noncombustibles such as metals, glass, and organic
liquids may be introduced into the system, and require downstream maintenance and
cleanup of oxidation products and slag.
2.5.2 Feed System
The ram feeder is basically a piston operated component which forces waste into the combustion
chamber. Maintenance and cleanup are required when material becomes lodged behind the ram
face. Installation of a plug conveyor alleviates this problem. Piston seal failure is another
routine operational problem, and seal replacement is generally required after several hundred
hours.
2-25
-------
The screw type feed mechanism experiences gradual wearing of surfaces caused by abrasive
materials. Should the wear become extensive, a chromium based "sweat-on" paste or powder
can be welded to the surfaces. These abrasion-resistant materials significantly extend operational
time. Inspection for feed build-up would be a normal maintenance task during down time
inspection.
2.5.3 Combustion Chamber
2.5.3.1 Rotary Kiln. Typical rotary kiln operation involves introducing the shredded feed into
the rotating kiln operating at 1400-1800 °F for a nonslagging kiln (2800 °F for slagging kiln),
with an accompanying air flow of several hundred thousand actual cubic feet per minute.
Particle size distribution of the feed is the determining factor for feed entry or load point.
Subsequent to initial incineration, the gases pass through a secondary combustion chamber in an
atmosphere of 6-8 percent excess oxygen. For RCRA waste, the secondary combustion chamber
operates between 1600-1800 °F with a residence time greater than 1 second. For TSCA waste
(PCBs), a temperature of 2100-2400 °F and a residence time greater than 2 seconds is required.
The solids from the primary combustion chamber go to the ash collection unit.
Routine maintenance procedures include inspection of the refractory lining to ensure integrity
and inspection of drum internals for possible buckling which can result from uneven heating of
the kiln and degradation of the kiln seals. Seal replacement, bearing lubrication, burner nozzle
replacement, and general cleaning are standard maintenance procedures.
2.5.3.2 Fluidized Bed. Fluidized bed reactor operation involves introducing feed which has
been pretreated so that the typical feed particle diameter is 0.5 inch or less. Air (typically at
a temperature of 1020 °F for radwaste) is fed to a bed containing the feed materials via a hot air
distribution system composed of nozzles connected to a header containing the hot air. As the
velocity of the air increases, the granular bed material (feed) becomes suspended in a churning
gas-solids mixture having physical properties similar to a fluid. Combustion gases are then
processed in the air pollution control system. Typical maintenance procedures include cleaning
2-26
-------
slag which forms in the system, maintaining air distributor nozzles which tend to foul after
extended operation, instrument monitoring such as cleaning of the thermocouple wells which
tend to gather hydrocarbon deposits from the bed, and recalibration of the oxygen and carbon
monoxide monitors.
2.5.3.3 Controlled Air Incinerator. Operating procedures for a typical controlled air incinerator
begin by feeding the pretreated waste to the first chamber (incinerator) either batch wise or quasi-
continuously. The flow of air into the unit is limited to stoichiometric or preferably below
stoichiometric conditions. The oxygen concentration is controlled to keep the local temperature
(at each point of the combusted material) in the appropriate range (1300-1800 °F). The oxygen
concentration is adjusted by partial recycling of off-gas after the water cooling step. The
combustible solid particles and combustible gases leaving the bottom of the incinerator are then
burned in the upper part of the first chamber and finally in the second chamber (afterburner).
The temperature in the afterburner is maintained between 1650 and 2000°F by means of
additional fuel. Total combustion is achieved if the oxygen concentration in the afterburner is
greater than 6 percent by volume. This is typically verified by on-line oxygen analyzers. In the
operating mode, wastes are charged batchwise with the feed depositing on a stationary hearth
in the lower chamber where underfire air is used to support combustion of wastes at near
stoichiometric conditions.
The secondary chamber is operated to provide the necessary residence time for completion of
combustion reactions. Secondary chamber residence time is designed to operate with a minimum
of 1.25 seconds hold-up time.
Typical maintenance procedures for a controlled air system include keeping the pathway from
primary combustor to secondary combustor clean of agglomerated debris, thermocouple
calibration, ensuring scanners are operating, and cleaning up slag that forms from
noncombustibles entering the feed stream.
2-27
-------
2.5.4 Air Pollution Control System
2.5.4.1 Quench Tower. Subsequent to incineration, hot gases and remaining particles are
transferred to a quench tower. The quench tower serves to cool the hot incinerator gases and
prevent high temperature damage to air pollution control equipment. The off-gas exits from the
incinerator or from the afterburner at a temperature of 1650-2370 °F. The off-gas is cooled by
injection of aqueous scrubbing solution directly into the off-gas stream. In the inlet of the
quench tower, some of the scrubbing solution evaporates and the off-gas is rapidly cooled down.
A long contact time is necessary to achieve a vapor-water balance for these temperature
conditions. The temperature of the quench solution at the inlet is kept in the range of 100-115
°F by an external heat exchanger. The acids produced by washing gases such as SO.' HC1, and
HF are neutralized by addition of NaOH or KOH. A part of the solution is removed
continuously or batchwise from the cooling circuit and replaced by scrubbing solution from the
system.
Typical operating problems involve maintaining proper water level in the tower sump,
maintaining proper water flow rates, and controlling tower and water temperatures. Typical
maintenance includes replacing nozzles and cleaning nozzle blockage and/or corrosion of the
nozzle. This is a result of the action of the corrosive incinerator gases reacting with the
moisture in the gases. Pump seal replacement, controls maintenance, and corrosion prevention
(painting, surface passivation) are also typical.
2.5.4.2 Venturi Scrubber. The cooled gases and suspended liquids and solids are usually
transferred to a high energy venturi where the particulates in the stream impinge with the water
droplets carried from the quench tower. A demister system usually operates downstream of the
venturi. Maintenance problems generally focus on corrosion.
2.5.4.3 Baghouse Filter. Baghouse filters made from teflon fleece are used for off-gas
separation and filtration in a temperature range higher than possible for HEPA filters. These are
also used as prefilters to reduce the clogging rate of HEPA filters.
2-28
-------
When acid gases are present, the filter material used is normally teflon felt, formed into
cylindrical bags. Normal operating conditions include a gas velocity of 1 ft/sec at a temperature
of 390 °F and an absolute pressure of 30 psia. In such conditions, with the gas containing about
30 percent water by volume, the residual dust content after filtration is sufficiently low to be
removed by HEPA filters. Standard operating procedures dictate that teflon filters not be
operated above 446 °F for extended periods. Protection against overheating is obtained via a
temperature alarm which automatically opens a bag filter bypass valve. If glass fibers are used,
the operating temperature is in the range of 400-535 °F.
The baghouses are made of stainless steel to resist corrosive environments (HC1, SOz) up to
temperatures of 750 °F. The collected dust accumulates in a hopper. A typical baghouse is
covered by glass wool and aluminum sheeting. This cover acts as an insulator to prevent
condensation on the wall and possible acid corrosion. The bags are sometimes mounted on
metal frames attached to a venturi with a cleaning jet. Maintenance procedures involve
inspection to detect breakage of the bags. Inspection is accomplished by unscrewing and
removing a manhole plate.
2.5.4.4 Electrostatic Precipitators (ESP). In electrostatic precipitation, solid or liquid
particulates suspended in a gas stream are negatively or positively charged and passed through
an electric field, which forces the charged particles to separate from the gas stream and
accumulate on collecting plates for proper operation. Insulation of the high voltage is necessary.
Electricity is supplied as 25-50 KV DC.
The dust layer on the collecting plates is periodically removed by an internal or external rapping
system. An internal drop hammer rapping system provides a greater force to the collecting
plates, but external systems are easier to operate. However, the operating efficiency of the
external system is lower since electrical energy must traverse the entire system to reach the
collecting plates.
2-29
-------
The operating range for electrostatic precipitators is generally dependent on the off-gas velocity,
the presence of conductive material or water droplets, and temperature. The nominal
temperature range is 300-340 °F. Maintenance centers on hydrocarbon deposits which can
produce short circuits, possible corrosion of plates, and high collector plate loading.
2.5.4.5 Wet Electrostatic Precipitator (WESP). WESPs are similar to ESPs except there is a
wet spray in the inlet section to cool the stream, adsorb gases, and collect coarse particles, and
the collection electrode is wetted to flush away collected particles.
Operating procedures include maintaining the proper liquid-to-gas ratio (typically 5 gal/1000 scf)
and a pressure drop from 0.1 to 1.0 inch of water. Typical maintenance includes periodic
washing to prevent particle accumulation on the walls and unblocking nozzles.
2.5.4.6 Packed Tower. As previously discussed, packed towers are used to remove gaseous
components. Operating and maintenance procedures center on water flow, water level, gas flow
rate, tower water distribution, sump level control, unplugging the water flow system, removing
sludge buildup in tower internals, and pump maintenance. Operating efficiency for removal of
NO" or SO. is enhanced by addition of an oxidizing agent such as oxygen or hydrogen peroxide.
2.5.4.7 Condenser. Condenser operation involves cooling the water vapor and separating it
from the stream. The condenser is merely a heat exchanger; it has no moving parts. Thus
standard operations consist of maintaining a proper cooling water flow rate and controlling the
temperature drop across the condenser. Maintenance includes removal of volatile metals which
form, over time, in the tubesheet. Corrosion protection is accomplished via a polymeric gasket
replacement, when required. Tube replacement, if erosion occurs, is another nonroutine
maintenance function. Tube fouling, which reduces the exchanger performance because of a
reduction in the overall heat transfer coefficient, is also a maintenance concern.
2.5.4.8 HEP A Filters. The loading capacity for HEPA filters is rather low compared to other
filters. For this reason, HEPA filters are often protected by prefilters, particularly in high dust
2-30
-------
concentration applications. Use of prefilters is advised if the dust concentrations exceed 0.06
Ib/fts. Operating parameters for HEP A filters are listed in Appendix 7, Table 5.
2.6 INCINERATOR EFFECTIVENESS
Incineration converts combustible waste into ash that is nonflammable, chemically inert, and
more homogeneous than the initial waste. Volume and weight reduction factors to 100 and 20,
respectively, are possible for uncompacted dry active waste, although the overall reduction is
generally lower in actual operation, depending on the method of ash immobilization and the
volumes of secondary waste generated. Loading rate is another measure of effectiveness.
Loading rate is a measure of incinerator efficiency described as feed flux; the higher the loading
the more efficient the combustion. Actual operating values for this parameter are not available
for LLW incinerators.
The efficiency of the off-gas cleaning system for radioactive waste can be obtained by calculating
the system decontamination factor (DF). The system DF is the ratio of the radioactivity in the
feed waste to the radioactivity released subsequent to incineration and off-gas treatment.
DF = Input radioactivity
Output radioactivity
The effectiveness, or removal efficiency, of a given air pollution control component is defined
as:
Removal efficiency = Input activity - output activity x 100 percent
Input activity
= (1 - I/DF) x 100 percent
2-31
-------
Decontamination factors and calculated removal efficiencies for air pollution control components
are given below.
Component
Scrubber
HEPA filter only
HEPA filter + prefilter
Venturi
Electrostatic precipitator
Bag filters
Condenser
Baghouse filter system
Decontamination factor
50-100
100
1000
100
20
15-58
100
100
Removal efficiency
98% - 99%
99%
99.9%
99.9%
99.9%
93.33 - 98.3%
99.9%
.99%
Removal efficiency can also be expressed as a function of particle diameter. Listed below are
actual decontamination factors and removal efficiencies for system components.
Particle diameter, urn
2
10
20
0.3
0.5
1
Component
Decontamination
factor
Venturi
Venturi
Venturi
Bag filter
Bag filter
Bag filter
20
85
99.9
95
96
97
Removal efficiency (%)
95
98.82
98.99
98.95
98.96
98.97
Ash distribution is a further measure of component effectiveness. Typical values obtained from
the Trin Vercellese (Italy) incinerator are:
Component • Ash distribution, percent
Incinerator 93.7
Venturi 1.0
Bag filter 5.2
Beyond bag filter (balance of unit) 0.04
2-32
-------
Lastly, the DF for metals is a measure of effectiveness. Typical decontamination factors for
radioactive metal constituents are:
Metal
Equipment
Co-60
Co-60
Sr-90
Sr-90
Total system
HEPA filter
Scrubber
HEPA filter
15,000
200
3.5
' 445
2.7 INCINERATOR RELIABILITY
Reliability is a measure of the dependability of a system, subsystem, or component. Reliability
coupled with the maintainability of a system, subsystem, or component produces a term known
as availability. In quantitative terms, availability is defined as:
Where:
A
MTBF =
MTTR =
MTBF x 100 percent
MTBF + MTTR
Availability (percent of time that the system, subsystem, or com-
ponent can operate)
Mean time between failure (reliability)
Mean time to repair (a measure of the capability of the unit to
operate)
For incinerator operations, this definition can be simplified to:
A = Time processing feed x 100 percent
Total time
2-33
-------
Reliability studies require rigorous mathematical approaches, their accuracy increases with the
size of the data base, and they are most effective when the units under evaluation operate
continuously. Because there is a general paucity of radioactive and mixed waste incinerator
data, and the limited existing data are from noncontinuous operations, it is not possible to define
availability for radioactive and mixed waste incineration. For comparison
purposes, it should be noted that the typical range for incinerators processing hazardous waste
is 40-80 percent availability.
Materials of construction are a significant reliability concern. Combustors as well as the APC
system can be adversely affected by improper materials selection. Rotary Mlns, for example,
must be designed and constructed so that the refractory lining and the kiln chamber are formed
of materials having similar thermal coefficients of expansion; otherwise, buckling will occur.
Another material failure directly related to reliability is the emission of volatile corrosive gases
from the incinerator system.
Slagging is another reliability factor. This is essentially the buildup of melted noncombustible
materials in the incinerator system that occurs when unsorted materials such as glass, certain
metals, and certain polymeric materials enter the feed stream.
Because radioactive and mixed waste incinerators usually operate in a batch mode, reliability is
hampered by the startup, standby, and shutdown periods of operation. Longer operation periods
could increase reliability. Although not an actual failure mode, increased steady state operation
decreases the starting and stopping stress on components.
HEPA filter failure, primarily from moisture accumulation on the filter material and paniculate
buildup, is another mechanical failure mode. Heating the flue gas to vaporize the moisture will
help this problem and increase reliability. The configuration of the unit is an obvious
contributor to reliability; e.g., parallel HEPA filters have a higher reliability than series HEPA
filters. The interrelationship between operating procedure and equipment causes reliability
predictions based on a limited number of operating systems to be particularly difficult.
2-34
-------
Chapter 2 References
Cooley, Leland R. Incineration in Low-Level Radioactive Waste Management at the University
of Maryland at Baltimore. December 1987.
Martin, Lorenzo M. Notes on Incineration of Radioactive Waste. Consejo de
Seguridad Nuclear. Extract from Energia Nuclear, Spain 28 (148). March-April 1984.
Hultgren, Ake. Practices and Developments in the Management of Low and Intermediate Level
Radioactive Waste in Sweden. Studsvik Energiteknik AB, NW83/502. June 1983.
The Los Alamos Controlled Air Incinerator for Radioactive Waste Volume I: Rationale,
Process, Equipment, Performance, and Recommendations (Abstract only).
Volume II: Engineering Design Reference Manual (Abstract only)
Volume III: Modifications for Processing Hazardous Chemicals and Mixed
Wastes,LA-9427, Vol. 111. DOE/HWP-30. October 1987.
Ziegler, Donald L. and Johnson, Andrew J. Disposal of HEPA Filters by Fluidized Bed
Incineration. 15th DOE Nuclear Air Cleaning Conference, Boston. 1978.
Radioactive Waste Technology. New York, NY. American Society of Mechanical Engineers
1986.
HEPA Filters and Filter Testing. 3rd Edition, Bulletin No. 58ID. Flanders Filters, North
Carolina. 1984.
The Flanders In-Place OOP Test. Bulletin No. 381C. Flanders Filters, North Carolina. 1984.
Flanders Nuclear Grade HEPA Filters. Bulletin No. 812E. Type B Filter. Flanders Filters,
North Carolina. 1988.
Marshall, M. and Stevens, D.C. A Comparative Study of In-situ Filter Test Methods. In
Proceedings of the 16th DOE Nuclear Air Cleaning Conference held in San Diego, California
October 1980.
Treatment of Off-Gas from Radioactive Waste Incinerators. Technical Report Series No. 302.
International Atomic Energy Agency, Vienna. 1989.
Iroju, M. and Bucci, J. Savannah River Plant LLW Incinerator: Operational Results and
Technical Development. Presented at the Incineration of Low-level Radioactive and Mixed
Waste Meeting, St. Charles, Illinois. April 1987.
2-35
-------
Bergman, W. Review of Some Health and Safety Aspects of the Incinerator Planned for the
LLNL Decontamination and Waste Treatment Facility (DWTF). Lawrence Livermore National
Laboratory. December 1988.
Bergman-1990a, High Efficiency Steel Filters for Nuclear Air Cleaning, 21st DOE/NRC Nuclear
Air Cleaning Conference, Werner Bergman, 1990.
Bergman-1990b, High Efficiency Paniculate Air (HEPA) Filters in the Nuclear Industry;
Comments on Previous Reviews, Lawrence Livermore National Laboratory, Werner Bergman,
et al., July 19, 1990.
Ruedinger-1988, The Realization of Commercial High Strength HEPA Filters, 20th DOE/NRC
Nuclear Air Cleaning Conference, V. Ruedinger, et al., August 1988.
Ruedinger-1986, Development of Glass-Fiber HEPA Filters of High Structural Strength on the
Basis of the Establishment of Failure Mechanisms, 19th DOE/NRC Nuclear Air Cleaning
Conference, V. Ruedinger, et al., August 1986.
High Efficiency Gas Adsorbers (HEGA). Charcoal Service Corporation. Bulletin No. 283A,
Bath, North Carolina.
Los Alamos Incinerator Documents:
Treatment Development Facility, Controlled-Air Incinerator, Runlog. Feed Summary for the
Los Alamos Controlled-Air Incinerator System (1978-1987).
Radioactive Operations in the Los Alamos Controlled-Air Incinerator. Appendix D: Radiation
Protection and Plant Instrumentation (From FSAR). Appendix E: Airborne Radioactive
Emissions History (1981-1987).
Air Quality Permit Application for the Proposed Low Level Waste/Mixed Waste Incinerator,
Technical Area 50, Building 37, February 1988.
A review of the report, "High Efficiency Paniculate Arresters in the Nuclear Industry," by
Joseph Goldfield, Consulting Engineer, Reviewer: Ronald C. Scripsick, Industrial Hygiene
Group, LANL, August 17, 1989.
Rocky Flats Incinerator Correspondence and Documents:
Draft Waste Analysis Plan, September 18, 1987.
Regulation Permit Activities for the Rocky Flats Mixed Waste Fluid Bed Incinerator Unit, April
22, 1987.
2-36
-------
3. Technologies for Monitoring Incineration and
Radionuclide Airborne Emissions
The incineration of low-level radioactive and mixed wastes results in the release of airborne
emissions. Emissions include chemical compounds, gases, vapors, and aerosols in the form of
fumes and particulates. Depending on the radiological, chemical, and physical properties of the
incinerated waste, emissions may consist of a wide spectrum of radioactive aerosols (AMB86,
C0081, INC89, OPP87). Airborne release rates also depend on the combustion process and the
type of off-gas treatment system installed on the incinerator (INC89). The types of treatment
technologies most frequently used include high efficiency particulate air (HEPA) filters and
carbon adsorbers (IAE89). Such treatment technologies have proven effective in most routine
applications but are ineffective for some radionuclides, primarily tritium, carbon-14, and iodines.
Tritium is exhausted as water vapors, carbon-14 as carbon dioxide, and iodines are combined
with other organic constituents present in off-gases. For these radionuclides there are no reliable
engineered systems with which to control such emissions. Since airborne radioactive emissions
are regulated by State and Federal agencies, it is necessary to (1) demonstrate that the
incinerator is not releasing radioactive materials in excess of maximum permissible
concentrations (MPCs) and (2) conduct periodic radiological assessments for characterization of
offsite exposures and for historical and record keeping requirements (AMB86). These
requirements are met by sampling and monitoring stack releases for radioactivity and release
rates.
3.1 RADIONUCLIDE AIRBORNE EMISSIONS MONITORING TECHNOLOGY
Conceptually, the methods for sampling and monitoring radioactive emissions are similar to
those used for sampling nonradioactive emissions. In fact, some methods identified by the
Environmental Protection Agency to demonstrate compliance with the Clean Air Act (EPA89)
are useable with little or no modification. In simple terms, a sample is withdrawn from the
exhaust stack at a specified rate, conditioned to minimize sample losses, and collected in a
manner which accounts for the physical properties and chemical forms of the radionuclide(s) of
3-1
-------
interest. The sampling system, known as a sampling train, includes the sampling probe, sample
collection or monitoring device, a flowrate meter, a sampling pump, and the associated
electronic controls and display monitors. The sampling system can be fully automated, manually
controlled, or a combination of the two methods. Depending on monitoring requirements, stack
releases can be monitored in real time or by indirect methods. For example, stack samples can
be collected automatically, removed manually from the sampling train, and analyzed at a later
time. Sample analyses can be performed in real time by continuously operating radiation
monitoring systems, or at a later time in a laboratory. Real-time stack monitoring obviously
offers the advantage of being able to detect current trends in stack emissions and to terminate
immediately the incineration burn if a pre-specified concentration limit is exceeded. This
approach also has the advantage of detecting rapidly changing conditions and monitoring system
parameters that, if unchecked, could result in an unsafe operating status. In this mode, the stack
radiation monitoring train doubles as a process control system.
3.1.1 Stack Off-Gas Sampling Systems
The stack off-gas sampling system generally consists of several components operating as a unit.
The main purpose of the sampling system is to collect a representative sample of the effluent
stream. The EPA regulations, as well as proper practice, require that the sample be withdrawn
isokinetically; i.e., the velocity of the sample gas at the inlet of the sampling nozzle must be
equal to the velocity of the off-gas effluent in the stack (EPA89, ACG78). Failure to meet this
requirement would result in an inaccurate representation of particle size distribution (ACG78).
This requirement is not as critical for gaseous emissions, but since gases and particulates are
always released simultaneously, it is normal practice to sample isokinetically for both using a
single probe. Depending on the type of incinerator, the system can be operated in an automatic
or a manual mode. Depending on its complexity, the system requires such utilities as electrical
power to run pumps, valves, heat tracing elements for sample conditioning, and to power system
interlocks and local and remote alarms; compressed air or bottled nitrogen tanks to purge
sampling lines; and water to cool system components (NRC86, SAI85, SOR89, BUN89, AER84,
TER88, and VIC_J.
3-2
-------
Three basic types of sampling trains and components are commonly used. A typical radionuclide
sampling and analysis system is shown in Figure 3-1. This system can neither detect nor
measure some radionuclides; e.g., tritium and carbon-14. Impingers or silica gel towers, as
indirect methods, are used for this purpose since they have been shown to effectively retain
water vapors and can be made to trap carbon dioxide. Some radiation monitoring systems
respond to other forms of radiation for which they were not originally designed or calibrated.
In such events, the detector(s) will detect radiation being emitted by the sample, but it will not
be possible to reliably measure or quantify the amount of radioactivity actually present. This
type of response, if not properly accounted for during calibration, may result in over or under
estimating actual off-gas releases.
The system shown in Figure 3-1 incorporates a sequence of three radiation detectors. The first
detects and measures radioactive emissions in paniculate forms using paper or glass fiber filters.
The second detects and measures radioiodines using activated carbon cartridges to capture both
elemental and organic iodines. Such cartridges are impregnated with potassium iodide (KI) or
triethylenediamine (TEDA) in order to increase the collection efficiency of organic compounds
(ACG78). The third detector measures radioactive gases by presenting a gas volume to the
detector.
A conceptual diagram showing an example stack monitoring system is shown in Figure 3-2.
This system uses a CaF(Eu) detector capable of operating at the stack gas temperature. By
measuring particulates collected at the stack gas temperature, the adverse effects of particulate
plate-out and deposition/resuspension are eliminated (SEGJ, In all stack monitoring systems,
some effluent components, particularly iodines, will plate-out onto sampling line surfaces. After
plating-out or depositing onto surfaces, iodines will later resuspend, remain suspended for a
time, deposit again, and the process repeats. Because of this phenomena, iodine concentrations
measured by the detector do not represent the true concentractions present in the stack.
Variables that control plate-out are sampling line construction material, diameter, length, and
bends; air flow rate; humidity; change in temperature; and temperature. Temperature is the
major controlling variable. The solution to plate-out is to place the detector on the stack or heat-
3-3
-------
Isokinetic
Nozzles
LEGEND
tSj Ball Valve, Manual
E " 3-Way Electric Valve
PT Pressure Transmitter
RE Radiation Detector
H Motorized Valve
RIC Ratemeter
FE Mass Flowmeter
FIC Flow Indicating Controller
FT Flow Transmitter
Motorized Valve
Fl Flow Indicator
Figure 3-1. Typical Radioactive Airborne Emission Sampling System
3-4
-------
-Stack Exhaust
Stack
• Iiokln.tic Notll*
Sample Flow
Stack Monitor
Inl«t
Sample
Return
Puro,e Ate Absolute
Pure.. Lint 1§) ©
&-
Moving
rarticulnt
Fixed
F^rtlc'il*
Incline
jr°
Samp|.
Peturn
Tritium Sampler ^Jta
KJ ucy
i T
*
O
Temperature
Figure 3-2. Conceptual Diagram Showing the Stack Monitor Location and Sampling Layout
3-5
-------
trace the entire length of the sampling line from the stack to the detector.
Figure 3-3 depicts an EPA-approved sampling system and method for the collection of
particulates. The method relies primarily on the collection of particulates on a filter followed
by a series of impingers. The sample is conditioned to minimize internal losses and maximize
absorption. The particulate filter holder is heated to prevent condensation and the impingers are
cooled in ice baths to enhance absorption. Obviously, the number of impingers can be
increased, and the composition and sequence of each scrubbing solution can be changed to trap
specific chemical species. Other than sampling parameters such as flow rate, temperature, and
differential pressure, this method does not provide any real-time indication of offgas release rates
or concentrations. The filter and impinger solutions are analyzed in a laboratory.
The third method, shown in Figure 3-4, is used to assess the presence and concentrations of
volatile organic compounds. This method relies on the collection of organic vapors on tenax,
charcoal, and silica traps. However, it does not provide any real-time indication of releases as
they occur. The traps, including the silica gel, are analyzed by laboratory methods.
The physical configurations of the systems discussed above are designed to facilitate the
operation of the system, sample changes, and maintenance and servicing. They are typically
configured to reflect specific facility design and operational requirements. The purpose and
operational features of each of the major components are discussed below.
3.1.1.1 Sampling Point Location. The sampling probe is installed in the stack at a location
downstream from any major air disturbances such as elbows, transition pieces, and branch
entries. The normal requirement is to locate the sampling point at a distance equivalent to at
least eight stack diameters downstream from the nearest air disturbance and more than two stack
diameters upstream from any other similar air disturbances (ACG84).
This location can also be determined empirically by taking measurements until the observed flow
rates are within 10 percent of one another at two separate locations (ACG84). The flow rate
3-6
-------
Ttmperaturs
Indicator
Thermocouple (behind)-' ff
"
JOOmL (ea) 0.1N NaOH Emptu Silica Gel
Mag nehelic Gauges
Figure 3-3. Typical EPA Particulate Airborne Emission Sampling Sytem
3-7
-------
Glass or Teflon Pro te
•*-CNrco«l Filter
(for leak checks)
Bulb
(for purging)
Glass Wool
Participate Filter
Dry Gas
Meter
Vacuum
Pump
Figure 3-4. Typical EPA Volatile Organic Sampling System
3-8
-------
across the diameter of the stack is measured by taking two sets of measurements at 90 degrees
from one another. The number of measurements across each traverse is dictated by the shape
and size of the stack pipe. For round ducts with diameters larger than 6 inches, at least 10
traverse points should be used for proper assessment of the cross-sectional flow-rate profile. For
square and rectangular stacks, the procedure involves dividing the cross section into equal square
or rectangular areas and taking measurements in the center of each. Enough measurement points
should be identified such that the distance between any two points is not more than six inches.
The total number of readings should be at least 16 (ACG84).
3.1.1.2 Sampling Probe Assembly. The sampling probe assembly typically consists of one or
more nozzles facing the out-going offgas flow (see Figure 3-5). The shape and size of the
sampling probe and nozzle are designed to minimize air-flow disturbances and collect particulate
and gas or vapor samples with the least loss. The probe is typically shaped such that little or
no internal deposition occurs for particulates (ACG78, ACG84, ANS69, KUR__). The sampling
probe should make a smooth turn with a radius wide enough to minimize sample deposition.
If reactive gases and vapors are sampled, some internal plating may occur. In this case, the
probe material should be selected so as to minimize this undesirable effect (ACG78, AMB86).
Depending on the design, the sampling probe assembly may also incorporate flow rate or
velocity sensors. Stack flow rate or exhaust velocity is measured by a pilot tube or electronic
anemometers (ACG78, KUR_J. These measurements are used to control electronically the
sampling flow rate by regulating the sampling pump or flow control valve. This information
is also used to correct sampling flow rates to conditions of normal temperature and pressure (25
degrees C and 760 mm of Hg) (ACG78).
3.1.1.3 Sampling Flow Rate. The sampling flow rate is dictated by several factors, including
offgas exhaust flow rate, type of sample collection device, instrument response, and desired
minimum detectable airborne concentrations (NRC86, BUN89, BAT83). Generally, these
factors are considered as operating specifications and are incorporated in the general design of
the sampling system. For example, a system with a higher flow rate is not necessarily better
3-9
-------
MOT SHIELDED S.S.
HIGH TEMPERATURE CABLE
TYPICAL SAMPLING NOZZLE.
• VARIOUS SIZES AVAILABLE
(1/4. 5/18, 3/1, 1/T)
SENSOR
• ELECTRICAL
CABLES
SAMPLE FLOW TO
* SAMPLING SYSTEM.
FILTER IMPACTOR, ETC.
FLOW
FLOW
Figure 3-5. Typical Isokinetic Sampling Probe
3-10
-------
since it may sample under anisoMnetic conditions, result in lower sample collection efficiency,
cause increased filter loading, or deplete trap or impinger solvent.
.3.1.1.4 Sample Collection. The sample is extracted from the offgas exhaust stream and
directed to a collection device. Depending on the physical and chemical properties of the
sample, different types of collection devices may be used. For particulates, the sample is
collected on glass-fiber filters, impingers, cascade impactors, or bubblers. If bubblers are used,
scrubber solutions are selected to account for the chemical properties of the sample and to
enhance absorption and retention (AMB86, BUN89, OPP87). For gases or vapors, the samples
are usually collected using impingers with appropriate solutions. Some gases and vapors may
also be collected on activated carbon cartridges or silica gels.
In some instances, the sample may be directed to a direct reading detector which provides an
instantaneous reading. These instruments may consist of beta or alpha scintillation detectors or
gamma or X-ray spectroscopy systems (ACG78, VIC_. SOR89, SAI85). The detection
capability of such systems depends on several factors, including the type of radiation detector,
sample flow rate, ambient background radiation levels, presence of two or more radionuclides,
and the selected radionuclides of interest on which the calibration is based. See Section 3.1.4
for more details on this subject. The sample can be collected on stationary particulate glass fiber
filters, moving filter tapes, activated charcoal cartridges, or presented as a gas volume to a
radiation detector.
Most sampling systems, because of the harsh operating conditions, are equipped with purge lines
to flush out residual gases or particulates between sampling batches. The sampling lines are
flushed with compressed air or bottled nitrogen. The length of the sampling line should be as
short as possible and have a minimum number of bends or turns to minimize internal deposition
(ACG78, ANS69).
Depending on sampling conditions, samples may have to be collected in a controlled
environment. For example, the sample offgas stream may have to be maintained at an elevated
3-11
-------
temperature to minimize water condensation and losses via internal plating (AMB86, OPP87,
ANS69). Experience has shown that when a sampling train is properly designed, little or no
radioactivity should pass through the filters or impingers. The following summarizes some test
results conducted on the TSCA incinerator system located at the Oak Ridge National Laboratory
(BUN89).
Proportion Collected (percent)
Form of Activity
Uranium
Alpha
Beta
Technetium
Filter
& Probe
100
99.25
99.30
99.70
Condensate
ND*
0.68
0.40
0.28
Impingers
ND
0.07
0.30
0.02
*ND means not detectable.
These data indicate that over 99 percent of the activity is retained on the filter and probe. These
values do not represent radiation monitoring system detection efficiencies, but rather the amount
of radioactivity retained in or on various components. Typically, less than 1 percent passes
through the filter and is collected either as condensate or in the impingers. Temperature
conditions are maintained with electric strip heaters and thermally insulated boxes which house
the sample collection devices. The presence of excess water vapor may cause particulate filters
to saturate and rupture as the differential pressure across the filter increases. If samples are sent
to impingers, the sequence of the scrubbers may also be important in isolating particulates
(BUN89). For example, the first two impingers could contain nitric acid to collect uranium,
while the next series of impingers could contain sodium hydroxide to collect elemental iodines
or other particulates. The next impinger could contain impregnated charcoal to trap methyl
3-12
-------
iodines or other organic iodine compounds and any remaining elemental iodines. The final
impinger could contain silica gel to collect any remaining moisture. In this example, samples
from each impinger would be analyzed for the presence and concentration of each radioactive
species. Obviously, this method does not provide the capability to measure airborne
radionuclide emissions in real time.
Typically, the analysis would be performed on a batch basis following each burn or conducted
periodically; e.g., daily. Sample collection and analytical frequency would have to reflect the
chemical stability of the samples, radioactive half-lives, regulatory requirements, and established
minimum detectable concentration limits.
3.1.1.5 Sampling Pump. The sampling pump provides the driving force to draw the sample
from the stack and through the various collection devices (ACG78). The type of pump most
often used is a constant flow-rate pump which adjusts automatically to changing sampling
conditions; e.g., increases in filter loading. Since isokinetic sampling conditions must be
maintained, the sampling flow rate can be adjusted by controlling the pump flow rate or via a
flow-control valve. The sample flow rate is also adjusted to account for differential pressures
and moisture content of the sample stream. Such corrections can be made electronically or
manually depending on the sophistication of the sampling system. These functions are typically
monitored and controlled by flow rate, mass, or velocity sensors and controllers (ACG78,
KUR__ ). Finally, the pump's exhaust is returned to the stack, at a point downstream from the
sampling point. The pump's flow rate must be regularly verified and calibrated to ensure that
operating characteristics have not degraded beyond the useful performance range (ACG78).
Experience has shown that sampling systems are also prone to frequent failure and require
extensive maintenance (IRU ). The accumulation and condensation of corrosive vapors or
gases in sampling lines and components cause rust and corrosion damage. Typically, particulate
residues accumulate in sampling lines, valves, and components and eventually such systems
become plugged and no longer meet original performance specifications. Accordingly, sampling
system designs should consider the use of inert materials, system components that can be quickly
3-13
-------
changed and easily cleaned, and selection of parts and equipment known for their durability and
reliability.
3.1.2 Real-Time Radiation Monitoring Systems
Very complex systems are required to monitor in real time the very low radionuclide
concentrations that may be discharged from incinerator stacks. Real time monitoring requires
alpha, beta, and gamma analysis of particulates and gaseous species with widely different
collection characteristics. While several different real time, or near real time, systems have been
installed, for example, beta/gamma systems on nuclear power plant exhaust stacks, none have
been installed on incinerator stacks.
Sampling systems that incorporate a real-time radiation monitoring system rely on passing or
collecting the sample next to a radiation detector (ACG78). For alpha emitters, the monitoring
system may be equipped with silver activated zinc sulfide. For beta emitters, the detector may
use a plastic scintillator. For gamma or x-ray emitters, the detection system may rely on a
sodium iodide or germanium detector (NCR78).
Some monitoring systems use hybrid designs combining different detection methods. For
example, one method combines alpha and beta scintillation media as one unit. This method
relies on the different attenuation and response properties of beta plastic and alpha ZnS(Ag)
scintillators. Another approach involves placing two separate detectors to measure the
radioactivity collected by a single-filter. For example, one detector could measure total beta
activity while the other could detect total gamma activity or operate as a single channel analyzer
targeting one radionuclide; e.g., iodine-125, iodinelSl, or cesium-137.
More sophisticated systems may rely on analytical spectroscopy by using a surface barrier
detector (Si) for alpha emissions and NaI(Tl) scintillation or solid state (HPGe, Si(Li)) detectors
for gamma or x-ray emissions. The pulses that such detectors generate are amplified, shaped,
collected, and displayed or stored as they are accumulated. In spectroscopy systems, the pulses
3-14
-------
are sorted as a function of energy since such systems generate pulses proportional to the
radiation particle that is detected. The information characterizing the size of the pulses is stored
in energy bins or channels. These data are displayed to generate a spectrum that characterizes
the radionuclides detected on the filter. Since each nuclide has a unique spectrum, this
information can be used to identify each radionuclide and quantify its concentration.
The information thus collected is typically displayed in real-time as a count rate, in counts per
minute (cpm) or second (cps), or directly converted to the proper radiological units, as a
concentration (uCi/mL) or release rate (uCi/sec). These results can be expressed by individual
radionuclide or in terms of total activity for a given distribution of nuclides. Typically, the most
sophisticated systems rely on algorithms which reduce the spectra to the respective radionuclides
and calculate release rates and concentrations given the stack exhaust flow rates (SOR89, SAI85,
VIC ). Given that waste is incinerated in intermittent batches, airborne radionuclide emissions
represent average concentrations or release rates, and a more appropriate radiological measure
may be the rate of change in concentrations or release rates. This information is typically
expressed as cpm per second or uCi/s per second (cpm = counts per minute and uCi/s = micro
curies per second). These sophisticated systems also have the capability to display this
information as a function of time showing trends and variations in concentrations or release
rates. Selection of the proper radiological unit for expressing airborne radionuclide emissions
depends on the type of monitoring system installed, its degree of sophistication, reporting
requirements, State or Federal regulations, and license conditions imposed on the facility.
Finally, real-time radiation monitoring systems must be periodically calibrated against known
radioactive standards (ACG78, NCR78). The operating characteristics and response of such
instrumentation must be known over a wide range of radiation emission energies and anticipated
radioactive concentrations. As discussed in Section 3.1.4, the detection limits associated with
such instrumentation vary significantly. Generally, detection limits are system specific and are
not constant. Detection limits are derived as part of the calibration procedures and take into
account an anticipated mix of radionuclides, sampling flow rates, and the response characteristics
of the radiation detectors or analytical methods.
3-15
-------
3.1.3 Indirect Radiation Monitoring Methods
Stack samples need not always be monitored in a real-time mode. In fact many institutional
incinerators rely on manual monitoring methods which are implemented for individual burns
(C0081, EGG82, LAN83, WM85). Samples are collected using a simple pump and^ sample
collection device or elaborate systems as described above. Once collected, the sample is
processed and analyzed in a laboratory. Radioanalytical procedures may employ a wide range
of methods, including gross alpha and beta counting, gamma, x-ray, or alpha spectroscopy, and
liquid scintillation counting (ACG78, NCR78). The selected analytical methods must be
implemented in accordance with good laboratory practices and comply with established
standards. There are well-documented procedures for analyzing stack samples (DOE83, EPA84,
NCR78, EPA89). The selection of a measurement method, given a specific application, is based
on such considerations as sample physical and chemical forms, anticipated range of sample
radioactivity, radionuclide(s) of interest, analytical frequency, specified or desired lower limit
of detection, availability of time and resources, and costs. In general, radiochemical analyses
are similar to classic wet chemistry procedures, except that the mass of the radionuclide(s) is
usually so small that conventional volumetric or gravimetric methods are not capable of
separating the radioactivity. The procedure, instead, relies on measuring the amount of
radioactivity which is emitted by the sample.
The radionuclide of interest, in its elemental form, may be separated from the sample matrix by
chemical extraction, precipitation, ion-exchange, electrolysis, distillation, and chromatography.
In other instances, it may simply be necessary to reduce the sample volume or mass by
evaporation, wet ashing (using, for example, nitric acid), dry ashing at low or high temperature,
or acid fluxes in order to prepare a sample for analysis. In any case, the selection of a specific
method must ensure that losses are minimized and quantifiable. It is common practice to
introduce a tracer element (stable or radioactive) to determine sample chemical recovery or
yield.
3-16
-------
Regardless of the method chosen, some common factors must be considered. The major factors
are:
a. Sample - Samples are analyzed using a procedure that stipulates sample size, volume,
and counting geometry or configuration. When analyzing alpha, beta, and x-ray
emitters, corrections must be made for sample self-absorption. Depending on the mass
and matrix of the sample, some of the radioactivity originating from the center of the
sample will not escape and, consequently, will not be detected and measured. Such
corrections are made empirically, or by using a sample with a mass which results in little
or no self-absorption. Usually, the sample mass is characterized as density thickness,
expressed in units of milligrams per square centimeter (mg/cm2). The density thickness
is used to correct for self-absorption for a given type of particle emission and its energy.
b. Sample Handling - All samples must be handled with care to prevent any accidental
loss of sample material or cross-contamination of the counting equipment and laboratory
work areas. Cross-contamination may cause erroneous conclusions. If a sample were
actually free of any radioactivity, any cross-contamination (e.g., from another sample)
would lead to the conclusion that the sample did contain some radioactivity. Preventing
sample losses during handling is also important because any loss would result in
underestimating the actual levels of radioactivity. Accordingly, all samples must be
properly prepared for analysis.
Samples are typically contained in or on planchets, kept in solution in colloidal or
dissolved forms, electro- or flame-deposited on metal discs, or fixed on filter paper.
c. Instrumentation - Instrumentation must be selected to ensure that the radiation
detection principle applied will indeed detect and measure the radionuclide(s) of interest.
The operational features of the instrument must be well known, considering system
background count-rate, sample size or volume, calibration, counting gas, counting
efficiency, counting time, counting geometry, decay correction factors, and lower limit
3-17
-------
of detection. Given that the system has been calibrated, it is also necessary to verify
system settings, such as high voltage, energy gain, upper and lower level discriminator,
dead-time, counting gas flow rate, background and standard count-rates, and operational
stability.
3.1.4 Instrumentation Detection Limits
The use of a continuous stack sampling and monitoring system requires that the response
characteristics and detection limits be known. Table 3-1 summarizes the responses of several
commercial systems. It should be noted that these systems were not designed for use on
incinerators, and none have been installed on incinerators. The response characteristics of the
system are keyed, by calibration, to a specific radionuclide(s) which is used to determine release
rates and concentrations. Other radionuclides that are not detected by the monitoring system or
are beyond the range of sensitivity are inferred by scaling factors. The scaling factor is
sometimes established beforehand based on radioanalysis of the waste before incineration.
Another method used to derive the scaling factor relies on the known radiological characteristics
of the process stream from which the waste originates. This approach works best for waste
streams which are homogeneous with well-characterized radionuclide distributions and
concentrations. This method is particularly well-suited to liquid waste streams; e.g.,
contaminated oils, machining fluids, and liquid scintillation fluids.
For some radionuclides, as noted earlier, it is not possible to rely on continuous monitoring.
This is the case for tritium and C-14, for example, since there is no known reliable method to
measure either in real-time. The problem is compounded by the difficulty in determining the
presence and concentrations of tritium or carbon-14 in some specific waste streams. This is
particularly true for solid and bulk waste material but not for liquid wastes.
Depending on the sophistication of the continuous monitoring system, there is a need to
determine, a priori, the minimum detectable concentrations (MDC) that the monitor will reliably
measure. The concept of the MDC, also referred to as the lower limit of detection (LLD),
3-18
-------
Table 3-1. Summary of Stack Monitoring System Response(a)
Vendor
Sorrento:
Ludlum:
Model or
System
RD-56B
RD-59
Dual Channel
Dual Channel
Beta Air
Monitor 333-2
Iodine Air
Monitor 377
Type(b) of
Detector
B-Scint.
NaI(Tl)
B-Scint.
A-Scint.
GM Tube
NaI(Tl)
Sensitivity(c)
Value Nuclide
10-12
10-12
10-11
10-11
10-11
10-11
Part.
1-131
Sr-90
Am-241
Sr-90
1-131
Notes(d)
@ 3 SCFM
it ll
It ll
ll ll
@ 2 SCFM
Victoreen:
Gaseous Effl.
Monitor 940-1
NaI(Tl)
B-Scint.
10-12
10-9
EG&G-Ortec
Berthold: LB-150D
LB-151-1
LB-IIO
LB-IIO-A
Eberline:
AMS-3
Alpha-VIA
Gas Prop.
B-Scint.
Gas Prop.
Ion Cham.
GM Tube
Surface
Barrier
10-13
10-11
10-9
10-5
10-12
10-12
1-131
Cs-137
1-131
1-133
Gross
B-/Alpha
Gross B-
H-3/C-14
H-3
Tc-99
Pu-239
4 SCFM
3 SCFM
2 SCFM
(a) Data collected from vendors by telephone or technical brochure summaries.
(b) Detector systems: HPGeLi, high purity germanium-lithium semiconductor; B-Scint., beta
particle plastic scintillator; A-Scint., alpha particle plastic or silver activated zincsulfide
scintillator; NaI(Tl), thallium-doped sodium iodide scintillator; GM Tube, Geiger-Mueller
detector tube; Gas Prop., flow-through gas proportional detector; Ion Cham., flow-through
ionization chamber; Surface Barrier, diffused-j unction solid state surface barrier detector.
(c) Expressed in uCi/mL, e.g., 10-13 equals 1.0 x 10-13 uCi/mL.
(d) Nominal or typical values, actual flow rates may vary.
3-19
-------
Table 3-1. Summary of Stack Monitoring System Response(a), Cont'd
Model or Type(b) of
Vendor System Detector
SAIC Stack Isotopic HPGeLi
Monitoring Syst.
11
n
ii
n
11
n
n
ii
it
it
»
H
it
tf
n
it
it
II
.
Sensitivity(c)
Value Nuclide Notes(d)
10-13
10-10
10-9
10-10
10-10
10-11
10-10
10-9
10-10
10-8
10-13
10-10
10-10
10-9
10-10
10-11
10-11
10-10
10-10
10-10
Part. @ 2 SCFM
Mn-54 " "
Cr-51 " "
Co-58 " "
Fe-59 " "
Co-60 " "
Sr-91 " "
Sr-92 " "
Mo-99 " "
Tc-99m
1-131 " "
1-132 " "
1-133 " "
1-134 " "
1-135 " "
Cs-134 , " "
Cs-137 " "
Cs-138 " "
Ba-140 " "
Ce-141 " "
(a) Data collected from vendors by telephone or technical brochure summaries.
(b) Detector systems: HPGeLi, high purity germanium-lithium semiconductor; B-Scint., beta
particle plastic scintillator; A-Scint, alpha particle plastic or silver activated zincsulfide
scintillator; NaI(Tl), thallium-doped sodium iodide scintillator; GM Tube, Geiger-Mueller
detector tube; Gas Prop., flow-through gas proportional detector; Ion Cham., flow-through
ionization chamber; Surface Barrier, diffused-junction solid state surface barrier detector.
(c) Expressed in uCi/mL, e.g., 10-13 equals 1.0 x 10-13 uCi/mL.
(d) Nominal or typical values, actual flow rates may vary.
3-20
-------
addresses a procedure for determining the smallest amount of sample activity that will yield a
net count rate for which there is confidence, at a predetermined level, that the activity is due to
the sample rather than background (NCR78, DOE83, TS083).
Counting a radioactive sample or background will yield a series of measurements (which should
be distributed as a Poisson distribution) from which it is possible to establish the standard
deviation from a single measurement. The standard deviation can then be manipulated in the
same way as the Gaussian standard deviation to establish a confidence interval about the mean.
If a background count-rate and its associated standard deviation are established, this information
can be used to derive a lower limit of detection. For example, a sample count one standard
deviation above background would indicate the presence of activity in the sample 84 percent of
the time and false positives 16 percent of the time. If two standard deviations were used instead,
the presence of radioactivity would be detected 97.5 percent of the time, and 2.5 percent of the
time one would note false positives. Since the sample and background count rates have their
own distributions, the interaction of the two distributions becomes important as the sample
activity tends to approach background levels. When the total sample count approaches
background, the distributions overlap such that it becomes difficult to discern the difference in
radioactivity due to the sample from that due to background. The count rate that establishes the
lower limit of detection is defined by the overlapping region of both distribution curves.
Several factors can be controlled to enhance the detection limit for a specific measurement
method. Since the goal is to detect and reliably measure low radioactivity levels in the sample,
the detector must be located in an area of low background radioactivity (including both ambient
external radiation exposure rates and airborne concentrations). Some types of detectors are very
insensitive to external radiation and accordingly do not pose a problem in this regard. For
continuous air sampling systems, especially those designed to measure alpha radioactivity, the
problem is compounded by the presence of naturally occurring radioactivity; i.e., decay products
from radon (radon-222) and thoron (radon-220) due to the uranium and thorium decay chains,
respectively. Depending on the type of instrumentation and data/spectra reduction method used,
such systems may resolve overlapping alpha spectra and reject the contribution due to radon-
3-21
-------
thoron decay products. As will be discussed later, the presence of radon decay products can
complicate the interpretation of results generated by stack monitoring systems.
Radon gas decays into paniculate daughter products, which are retained on sampling filters. The
decay products, being themselves radioactive, decay and cause an ingrowth in activity,
eventually reaching an equilibrium with that of the first member of the decay chain. The
concentrations of radon decay products are rarely at equilibrium with their parent gas.
Typically, the decay products are separated and are present at a fraction of the equilibrium,
about 30 to 80 percent (NCR75). The typical outdoor radon-222 concentration is about
200 pCi/m3 and 5 pCi/m3 for radon-220 (NCR87). Accordingly, decayproduct concentrations
are always less than that of radon. The ambient concentrations of radon and its decay products
are known to vary by a factor of 10, depending on atmospheric pressures, temperature, soil
moisture, and temperature inversions. Typical diurnal variations cause radon concentrations to
peak early in the morning and drop off sharply in the afternoon (NCR87).
If, for example, stack emissions include americium-241 or plutonium-239, the instrumentation
must be able to discern the presence of radioactivity due to all radionuclides that decay by
emitting alpha particles. If the system relies on gross alpha counting methods, the detector will
not discern the different radionuclides. The results, expressed as total count rate, will represent
the sum total of the radioactivity retained on the filter and seen by the detector.
If, however, the system relies on alpha spectroscopy, the detector will segregate alpha emissions
and identify each radionuclide. Americium-241 decays by emitting 5.5 MeV alpha particles,
plutonium-239 emits 5.1 MeV particles, and the radon decay products emit several particles
ranging from 6.0 to 7.7 MeV (KOC81). (Only the major alpha emissions are cited here.) The
count rate associated with the detection of each alpha particle is stored in its respective energy
channel. Because of the random process of radioactive decay and interaction of alpha particles
with the detector, the presence of a radionuclide is represented by a series of Gaussian
distributions, one for each alpha particle. These emissions may result in overlapping spectra,
depending on the system's resolution. The respective contribution of one spectrum into another
3-22
-------
spectrum would have to be resolved either manually or via an algorithm. The system's energy
response is typically divided into regions-of-interest, each one identifying the presence of a
radionuclide. By using calibration methods, the response of one radionuclide in the region of
interest of another radionuclide is determined empirically or is mathematically fitted based on
a few measurements. These relationships are noted and used to develop a matrix and set of
simultaneous equations to calculate the true count rate and radioactivity associated with each
nuclide.
For illustration purposes, it is worthwhile to compare current maximum permissible
concentrations (MFCs) for plutonium-239 and americium-241. The Nuclear Regulatory
Commission's MFC for plutonium-239 is l.OxlO'12 uCi/mL and 4.0xlO'12 uCi/mL for americium-
241. Both MFCs are for insoluble forms based on 10 CFR 20, Appendix B, Table II, Col. 1
values for nonoccupational exposures. For the radon-222 and radon-220 concentrations noted
above, the corresponding radon decay product concentrations are I.Oxlfr10 and 2.5xlQ-12 uCi/mL,
respectively, assuming 50 percent equilibrium. When compared to the MFCs, it can be seen
that plutonium-239 and americium-241 concentrations fall within the range of radon decay
products normally encountered in environmental settings.
For continuous stack monitor operation under such conditions, the system, starting with a new
filter, will show a rapid rise in the count-rate, followed by a plateau which represents an
equilibrium between two competing factors, 1) the accumulation of radon decay products on the
filter media and 2) radioactive decay of radon progenies. Occasionally, the plateau would rise
and fall, depending on changes in ambient radon concentrations, filter dust loading, and
sampling flow rate. If the alarm trip points are set at some fraction of the MFC, which is
usually the practice, the monitoring system would most likely generate spurious alarms
coinciding with variations and increases in ambient radon decay product concentrations. The
cause for these alarms would be investigated to determine whether or not the alarm is the result
of spurious responses, due to some instrument malfunction, or real. The particulate filter would
be removed and subjected to several laboratory analyses to identify the radionuclides. In order
to confirm the presence of naturally occurring radioactivity, one of the steps would involve
3-23
-------
counting the filter at specific time intervals to observe the radioactive decay of the radon
progenies. Since americium-241 and plutonium-239 are both long-lived radionuclides, repeated
analyses showing short-lived radon progenies would be indicative that the alarm was caused by
naturally occurring radioactivity and not due to the operation of the incinerator.
Other factors may enhance the response characteristics of a stack sampling and monitoring
system. Such factors include selecting a type of detector which offers energy optimal response,
properly determined sampling flow rate, and short instrumentation response time. The sampling
flow rate is governed by two considerations. First, the flow rate should be such that it ensures
isokinetic sampling (discussed in greater detail above). Second, the flow rate should be
sufficiently high to meet the desired MDC objectives, given an established sampling frequency.
Ideally, longer sampling times provide lower MDCs.
The selection of the detector media and associated electronics (analog-todigital converter (ADC))
generally dictates the overall response characteristics of the system. For spectroscopy systems,
the ADC dead-time will depend on the amount of activity presented to the detector. The dead-
time refers to the time during which the instrument is busy converting and storing data in a
digital form and is not acknowledging any additional pulses from the detector. For the intended
uses, dead-times should typically be low (a few percent) and result in no significant data loss.
These losses are compensated by operating the system with the clock set to "live-time" which
automatically corrects for the dead-time.
Instrumentation can also be equipped with algorithms that automatically perform energy
calibrations, reduce spectra and data, and provide the means to subtract or reject count-rates due
to background radioactivity. These features generally facilitate interpretation of the data and
results as well as system operation. The problem with "canned" software/firmware packages
is that, as black boxes, they offer little understanding as to how the data are handled and
reduced. Vendors treat this information as proprietary, providing little or no additional
documentation other than that provided in the manuals. Consequently, it may be difficult or
even impossible actually to determine how the raw data (from a count-rate, in cpm) is converted
3-24
-------
to the proper radiological units (in uCi/mL or uCi/s). It is good radiological practice to
generate, using first principles, data and results manually during the initial calibration
procedures. The calibration test results and any associated calculations should be documented
and maintained as permanent records.
3.2 RADIATIONPROCESSMONITORINGTECHNOLOGYDESCRIPTION PRINCIPLE
OF OPERATION, AND APPLICATIONS
Real-time radiation monitoring systems can be used to warn the operator that certain conditions
are rapidly changing, to trip audiovisual alarms, or to activate some components. Typically,
sampling system trips issue warnings before terminating a process or isolating a component,
thereby giving the operator time to respond (IAE89, BAT83, NRC86, AER84). In some cases,
the monitor could automatically terminate the burn if the detected conditions would result in
unsafe consequences or cause releases to exceed established limits. For example, a sudden rise
in stack airborne radionuclide concentrations could indicate a massive failure of the off-gas
treatment system or the introduction of waste at unacceptably high concentrations.
In other instances, two or more incinerator process parameters may be fed into a logic circuit
to establish operating conditions that should warrant termination of the burn. For example, a
sudden loss of differential pressure across a HEPA filter bank and an immediate rise in
radionuclide concentrations or release rate would indicate a massive HEPA filter bank failure.
Given this scenario, the burn should be terminated as quickly as possible. Whether or not the
radiation monitoring system should directly terminate the burn must be weighed against the
potential consequences that this action could have on the incinerator itself. A sudden rather than
a controlled cooldown could irreversibly damage the refractory lining, warp some internal
components, or cause slagging solidification in certain parts of the combustion chamber and ash
receiver (IAE89, C0081). A more appropriate action might be to stop introducing additional
waste in the combustion chamber. For waste in a solid form, the action would involve shutting
down the ram or conveyor feeding the material to the incinerator. For liquid wastes, the process
would simply involve shutting down the injection pump. Following these actions, the incinerator
could then be brought to a controlled shutdown.
3-25
-------
For incinerators with elaborate off-gas treatment systems, the stack monitor could be used to re-
route exhaust emissions to standby HEPA filters. In this scenario, the alarm trip would cause
one damper to close and another to open. Such actions could be performed without upsetting
in operating conditions and would provide time to evaluate the event, its causes, and necessary
corrective actions.
3 3 APPLICABILITY OF NONRADIOACTIVE EMISSIONS STACK MONITORING
METHODS TO RADIONUCLIDES
As noted above, some sampling methods identified by the Environmental Protection Agency to
demonstrate compliance with the Clean Air Act (EPA89) are useable with little or no
modification (AMB86, INC89, BUN89). In principle, many of the sampling train components
are identical. The only difference revolves around the specificity of the pollutant being collected
or analyzed. In some cases, especially for some volatile organic compounds, the methods may
not always be compatible with one another. For example, if an impinger uses a solution that
enhances the absorption of a specific compound and it is also required to determine the
concentrations of tritium and carbon-14 via liquid scintillation counting, the impinger solution
could affect the photochemical luminescence process of the scintillation cocktail (OPP87,
NCR78, ACG78). The chemical could quench the scintillation process, thereby falsely
indicating that there is no tritium or carbon-14. Conversely, the impinger solution could
enhance the photochemical luminescence process and erroneously indicate very high tritium and
carbon-14 concentrations.
Another important difference revolves around the analytical procedures for determining the
presence of radioactivity. If a real-time monitoring system is used, sample collection and
processing are conducted under vastly different conditions than samples collected to characterize
the presence of organic compounds or metal oxides. In many radiation sampling systems, the
sample may not be readily recoverable or, if it is, the sample may no longer represent actual
conditions. This is the case for volatile organic compounds which may collect on paniculate
filters. In time, an equilibrium may be achieved between the sample collection rate and the
3-26
-------
evaporation rate, but it may still be impossible to determine reliably the equilibrium ratio. This
problem is further compounded by the presence of additional organic vapors which may compete
for collection and retention sites, thereby upsetting the equilibrium. Finally, as more particulates
are retained on the filter paper, the presence of solids may further upset this equilibrium.
A similar problem exists with the use of activated charcoal traps or cartridges. The presence
of organic vapors may poison adsorption sites, causing a breakthrough to occur and rendering
the charcoal incapable of capturing or retaining organic vapors or radioiodines. In this example,
degradation of activated charcoal cartridges or traps interferes with both radiological and
nonradiological characterization of air emissions. The installation of the sampling train and the
sequence of filters, charcoal cartridges or traps, and impingers must be designed in anticipation
of the pollutants being measured. In some instances, it may be necessary to establish redundant
sampling trains, one to characterize radionuclide emissions and the other for organic compounds.
This approach was used in conducting the tests and burn trials of the fluidized bed incinerator
at the DOE's Rocky Flats Plant (DOE86).
3.4 MONITORING RADIONUCLIDE CONCENTRATION IN INCINERATOR ASH
There are no instruments currently available for direct assay of alpha, beta, and gamma emitting
radionuclide concentrations in ash receivers. Direct assay research on power plant waste
indicates that two instrumentation techniques may be applicable to ash assay (EPRB7).
Collimated, calibrated gamma spectrometer measurements in combination with predetermined
scaling factors for difficult-to-measure nuclides can be used to quantify the gamma-emitting
nuclides in a waste form. Passive neutron counting technology, based on surrounding the waste
form with neutron detector tubes encased in moderator material has been used to measure TRU
content of power plant radioactive wastes. Neither of these techniques have been evaluated for
use on incinerator ash.
Initially, the hot ash must be cooled after it is removed from the incinerator. Some incinerators
are equipped with ambient radiation monitoring equipment, but such systems are installed only
3-27
-------
for occupational radiation protection purposes (IAE89, NRC86,1ER88, AER84). Some facilities
are also equipped with ambient airborne concentration monitors, again for the purpose of
radiation protection, since ashes could become airborne in immediate work areas and
subsequently be inhaled by workers.
The normal practice is to collect ashes manually and perform the necessary radiological arialyses.
Ash sample analyses are conducted by methods similar to those described earlier. The
processing of ash samples may involve chemical extraction, sample weighing, and sample
splitting (NRC83). Radioanalytical procedures may include a wide range of methods, including
gross alpha and beta counting, gamma, x-ray, or alpha spectroscopy, and liquid scintillation
counting (NCR78). Because ash samples are usually high in specific activity, the radioanalytical
time (i.e., sample counting time) may be reduced. Ash with high specific activity also allows
the use of smaller sample sizes, thereby facilitating sample processing and minimizing the
volume of analytical waste. As before, the selected analytical methods must be implemented in
accordance with good laboratory practices and must comply with established regulatory standards
or criteria.
Ash may also be subjected to other types of tests, for example TCLP toxicity, to demonstrate
whether or not the ash is a hazardous material. If the ash is radioactive, it may have to be
disposed of as radioactive waste and meet established waste acceptance criteria in terms of
radionuclide concentrations, presence and concentration of transuranic radionuclides, nuclear
criticality safety, and decay heat loads (EGG88). Such waste acceptance criteria require that the
physical and radiological properties of the ash be assessed to identify the proper disposal
method. Analyses may in part reflect Department of Energy, State, and Federal standards
(DOE89). For example, the analyses must characterize free standing liquids, chelating agents,
explosive, reactive, flammable, or pyrophoric materials, generation of toxic fumes or vapors,
and internal pressures.
For ash that has been stabilized by cement or other solidification media, the analyses must show
that the radioactivity will not leach out of the media for the anticipated disposal conditions. It
3-28
-------
also must be demonstrated that the solidification media will not degrade or crumble, given
disposal depths and pressures, presence of water, microbial activity, and radiation- or chemically
induced internal changes or degradation. Analyses are typically conducted under an established
set of procedures. If the ash is to be solidified before disposal, samples are first solidified on
a bench scale. Once the solidified ash samples have fully cured, several tests are conducted to
verify the behavior and properties of the solidified samples. The test results are documented and
compared to the waste acceptance criteria to determine whether or not the solidified samples are
in compliance. If the criteria have been met, the process is scaled up and applied to the bulk
ash volume.
3-29
-------
Chapter 3 References
AER84 Aerojet Energy Conversion Company; Mobile Volume Reduction System, Topical
Report No. AECC-4-NP-A, prepared for the Nuclear Regulatory Commission,
Sacramento, CA, November 4, 1984.
ACG84 American Conference of Industrial Hygienists; Industrial Ventilation, 18th
edition, Cincinnati, OH, 1984.
ACG78 American Conference of Industrial Hygienists; Air Sampling Instrumentsfor
Evaluation of Atmospheric Contaminants, 5th edition, Cincinnati, OH, 1984.
AMB86 Ambrose, M.L.; National Emission Standards for Hazardous Air
PollutantsCompliance Verification Plan for the K-1345 Toxic Substances Control
Act Incinerator, Martin-Marietta Energy Systems, Oak Ridge National
Laboratory, Oak Ridge, TN, K/HS-109, July 28, 1986.
ANS69 American National Standard; Guide to Sampling Airborne Radioactive Materials
in Nuclear Facilities, ANSI N13.1-1969, New York, NY, 1969.
BAT83 Battelle Columbus Laboratories; Safety Related Information for the Volume
Reduction Demonstration Facility, BCL-1801, (Rev. 3,12/16/86) Columbus, OH,
August 15, 1983.
BUN89 Bun, D.H.; Continuous Off-Gas Sampling System, Martin-Marietta
EnergySystems, Oak Ridge National Laboratory, Oak Ridge, TN, RQT-276,
March 1989.
C0081 Cooley, L.R.; Current Practices of Incineration of Low-Level Institutional
Radioactive Waste, EG&G, Idaho, Inc, EGG-2076, February 1981.
DOE83 Department of Energy; EML Procedures Manual, Environmental Measurements
Laboratory, New York, NY, HASL-300, 26th Edition, 1983.
DOE86 Department of Energy; Rocky Flats Plant Fluidized Bed Incinerator TestPlan,
Sampling Locations and Procedures, Appendix 4, Section D-5b (2)(c), p. D-4-31,
Document No. C07890010526, November 28, 1986, Rev. N. 0.
DOE89 Department of Energy; Integrated Data Base for 1989: Spent Fuel andRadioactive
Waste Inventories, Projections and Characteristics, DOE/RW-006, Rev. 5,
November 1989.
3-30
-------
EGG82
EGG88
EPA84
EPA89
EPR87
IAE89
INC89
IRU_
KOC81
KUR_
LAN83
NCR87
NCR75
Radioactive Waste Incineration at Purdue University, EG&G, Inc.Idaho National
Engineering Laboratory, DOE/LLW-12T, November 1982.
Informal Report: Low-Level and Mixed Waste Incinerator Survey Report,EG&G,
Inc. Idaho National Engineering Laboratory, EGG-LLW-8269, October 1988.
Environmental Protection Agency; Radiochemistry Procedures Manual, Eastern
Environmental Radiation Facility, EPA 520/5-84-006, Montgomery, AL, Aug.
1984.
Environmental Protection Agency; Final Rule and Notice of Reconsideration,
NESHAPS for Radionuclides, Appendix B to 40 CFR 61, FR Vol.54, No. 240,
51654 - 51715, December 15, 1989.
Electric Power Research Institute; Advanced Radioactive Waste Assay Methods,
EPRI NP-5497, November 1987.
International Atomic Energy Agency; Treatment of Off-Gas from Radioactive
Waste Incinerators, Technical Reports Series No. 302, Vienna, 1989.
The 1989 Incineration Conference; Incineration Basics Course, May 2, 1989,
KnoxvilleTN.
Irujo, MJ. and Bucci, J.R.; Savannah River Plant LLW Incinerator:
Operational Results and Technical Development.
Kocker, D.C.; Radioactive Decay Data Tables, Department of Energy,
DOE/TIC-11026, 1981.
Kurz Instrument, Inc.; Mass Flow Sampling and Isokinetic Systems, Monterey,
CA, undated document.
Landolt, R.R.; Evaluation of a Small, Inexpensive Incinerator for Institutional
Radioactive Waste, Health Physics, Vol. 44, No.6, pp.671675, June 1983
National Council on Radiation Protection and Measurements; Exposure ofthe
Population in the United States and Canada from Natural Background Radiation,
NCRP Report No. 94, issued Dec. 30, 1987.
National Council on Radiation Protection and Measurements; NaturalBackground
Radiation in the United States, NCRP Report No. 45, issued Nov. 15, 1975.
3-31
-------
NRC86 Nuclear Regulatory Commission; Safety Evaluation Report Related to theVolume
Reduction Services Facility, Babcock & Wilcox, Parks Township, PA, Docket
70-364, April 1986.
NRC83 Nuclear Regulatory Commission; Incineration of a Typical LWR Combustible
Waste and Analysis of the Resulting Ash, NUREG/CR-3087, Battelle Pacific
Northwest Labs, May 1983.
NCR78 National Council on Radiation Protection and Measurements; A Handbook
ofRadioactivity Procedures, Report No. 58, Washington, DC, November 1, 1978.
OPP87 Oppelt, E.T.; Incineration of Hazardous Waste - A Critical Review, JAPCA,
Vol. 37, No.5, May 1987, pp. 558-586.
SAI85 Science Applications International Corporation; Stack Isotopic Monitoring System
- Application and Technical Specifications, San Diego, CA, November 1985.
SEG_ Diagram from Mr. Bud Arrowsmith (Scientific Ecology Group) to Mr. Larry Coe
0 April 9, 1990.
SOR89 Sorrento Electronics, Inc.; Dual Alpha/Beta Fixed Filter ParticulateRadiation
Monitors for Plant 8 - USDOE Fernald, Equipment Manual, E-1151416, San
Diego, CA, December 1989.
TER88 Terrell, M.S.; Incineration Test Results of a Fluidized Bed IncineratorSystem,
Duke Power Company, Radwaste Engineering, Charlotte, NC, March 31, 1988.
TS083 Tsoulfanidis, N.; Measurement and Detection of Radiation, McGraw-Hill, New
York, 1983.
VIC Victoreen Inc.; Off-Line Gaseous Effluent Monitors - Systems Descriptions and
Applications, Cleveland, OH, undated document.
WM85 Swearingen, F.L Van; Waste Management 1985; Incineration of Microspheres,
Tuscon, AZ, March 1985.
3-32
-------
4. Consideration of Incinerator Accident and Abnormal Operation Scenarios
Consideration of incinerator accident/abnormal operations scenarios, their consequences, and the
options available to prevent or mitigate such events is important to ensure protection of the
public and workers from potentially harmful exposure due to releases of materials processed at
the incinerator. Potential incinerator-related accidents include the following:
Fires and Explosions
Fires during transportation, accumulation, and storage of incompatible material
Fire in waste (feed) material preparation
Catastrophic incinerator failure; e.g., explosions of a severity sufficient to cause
failure of the combustion chamber
Emissions Control Feature Failure
Filter failures
Vent pipe failures
Off-gas treatment system failures
Acts of Nature
Earthquakes
Tornadoes
Flooding
Transportation Accidents
Loss of Essential Utilities
Loss of power
Loss of water to scrubbers and for quenching ash
Many of the potential hazards are not associated solely or even primarily with the actual
operation of the combustion process but rather with one of three broad stages of incinerator
operation: the gathering, storage, and handling of the incinerator feed material, the
treatment/release of effluent gases, and the handling, storage and disposal of liquid and solid
4-1
-------
effluents. Usually the potential for the largest releases of radioactive or hazardous materials falls
into one of these stages.
Determination of which specific accidents pose the greatest threats, and what process or emission
controls could be used for prevention/mitigation, can only be done on a case-by-case basis using
the actual design characteristics and operating conditions of a proposed incinerator to generate
an assessment of possible accident scenarios and associated impacts for each individual situation.
For example, the characteristics of the feed material (e.g., solid or liquid, Btu content, chemical
form) and the method of its storage (tanks, building equipped with fire detection capability and
sprinklers, etc.) can significantly affect the likely accident scenarios. As noted earlier in this
report, successful incineration of waste material depends on a relatively uniform and consistent
waste feed. Considerable attention must thus be given to feed preparation. On the other hand,
the nature of hazardous and mixed wastes is such that there is a considerable incentive to
minimize any additional handling after the waste has been generated. This poses a dilemma for
the designers and operators of waste incinerators. In practical applications, considerable
variation in feed materials may be present. The following wide range of waste types intended
for incineration as mixed waste at one proposed facility (LLNL) illustrates the potential for
abnormalities caused by nonuniform waste feed.
chlorinated and other organic solvents 25 %
oils and greases 20%
oil/water and other organic/water mixtures 28 %
organic sludges and still bottoms 3%
low-level radioactive solids and containers 17%
nonradioactive solid waste 7%
Range of btu values per Ib: 650 - 18,000
Percent range of water content: 0-90 percent
As a second example, the design of the off-gas treatment system must be evaluated (what is the
sequence of the treatment stages; e.g., are the gases adequately cooled and dried before reaching
HEPA filters, or, if the off-gas filters fail will building ventilation filters provide backup
4-2
-------
protection). Filtering of off-gases is typically a combination of an aqueous scrubber to cool the
exhaust and neutralize and remove acidic compounds followed by a HEPA filter, possibly
supplemented by a charcoal filter to capture organic vapors and iodine. Total or partial loss of
effective filtering capacity could result in releases of mixed waste particulates, including heavy
metals and iodine-131. It is important that there be real-time monitoring of the performance of
the HEPA filters and other emission control devices to ensure they are operating at peak
efficiency.
HEPA filters are the most common air pollution control device for particulates used in the
nuclear industry. Probably the most critical component in controlling radioactive emissions,
HEPA filters are essentially delicate structures. They can sustain structural damage relatively
easily under conditions of higher-than-designed-for rates of airflow, shock waves (for example,
as a result of explosions in the incinerator), higher-than-designed for temperatures, excess
humidity, and excess paniculate deposits.
A review of the incinerator proposed for LLNL, for example, noted that the HEPA filters
designed for controlling the off-gases would be subject to failure as a result of moisture buildup,
temperature and pressure surges unless major design changes, including the installation of a
prefilter, were implemented (BER88). The emission control system at the Los Alamos CAI is
equipped with a quench tower to cool the hot exhaust gases, followed by a wet alkaline scrubber
to remove chloride and other acidic gases after which a condenser should remove most free
liquid. The dried exhaust is ducted to the HEPA filter. Because the filter medium is made
primarily of paper that would be severely weakened by exposure to water, it is important that
essentially no moisture be allowed to reach the HEPA filters.
New high strength HEPA filters reportedly have been developed in Europe that appear to have
a much greater capacity for withstanding adverse conditions such as excess heat and humidity
or high air flow. These filters are being manufactured by European firms and are being installed
in German nuclear facilities (BER88).
4-3
-------
Finally, as a third example, the storage and handling of the solid and liquid effluents must be
reviewed (e.g., could an accident or human factor result in a release from a line or tank that
would release radioactive or toxic scrubber liquors to the environment or release dry ash to the
atmosphere). Tanks containing feed material typically are equipped with vent pipes. Bulk
storage units also contain pressure relief valves. Failure of these components could result in
material being vented directly to the atmosphere without passing through the filtration system.
4.1 EXAMPLE ANALYSES OF INCINERATOR ACCIDENT SCENARIOS
As noted earlier, the specific design parameters and operating conditions of each incinerator, in
relation to the range of radioactive and mixed waste it is intended to burn, must be analyzed to
determine likely accident scenarios and evaluate their consequences. The descriptions that
follow summarize analyses that have been performed for several incinerators described in
preceding chapters. These cases are used here only as examples. Subsequent changes in design
or operating conditions at the incinerators for which they were developed may have altered the
likelihood or consequences of any given scenario, however, they serve to illustrate the wide
variations that can occur in accident scenarios and 'consequences.
4.1.1 Scientific Ecology Group (SEG)
In its NESHAPS permit application to the EPA, SEG evaluated the radiological impact of two
major accidents: (1) the failure of the heat removal system resulting in thermal destruction of
the flue gas filtration system and subsequent release of unfiltered radioactive ash to the
environment, and (2) a pressure excursion in the incinerator resulting in rupture of the pressure
release diaphragm, release of ash to the incinerator building, and partial ash release to the
environment (SEG88). These accidents were evaluated for radiological impact on the
environment by determining the approximate radioactive release to the environment and
determining the resulting dose by comparison to previous AIRDOS-EPA runs. The following
descriptions are quoted from the NESHAPS application.
4-4
-------
"FAILURE OF THE HEAT REMOVAL SYSTEM - If feed water to the heat
removal system were to fail catastrophically and the incinerator could not be
cooled to less than 400 degrees Fahrenheit before baghouse and HEPA filter
destruction occurred, the radioactive ash inventory (up to about 5 kg) trapped on
the filters would be released. Within 4 minutes the emergency cool-down system
would cool the incinerator to less than 400 degrees Fahrenheit and the redundant
filtration system would be switched in. Even if the redundant filters could not be
used, the system ventilation could be stopped at about 400 degrees Fahrenheit and
further releases would cease. Besides the radionuclide inventory trapped on the
bag filters and HEPA filters, a much smaller quantity of additional unfiltered
radioactivity in flue gases would also be released. Five kilograms of ash have
about the same radionuclide content as one year of routine releases except that the
iodines, technetium, carbon, and tritium would not be present in the ash, having
already been released routinely."
"PRESSURE EXCURSION IN THE INCINERATOR - If a transient
overpressure condition occurred such that the pressure release door near the top
of the incinerator gave way, a small amount of ash would be blown into the
incinerator building, perhaps as much as a few kilograms. To a large extent, this
ash would be contained in the building and could create a temporary airborne
condition for workers. However, since the plant ventilation is also HEPA
filtered, essentially no release to the environment would occur. It should be
noted that significant overpressure can only be caused by explosive materials such
as large oxygen bottles. The SEG sorting process described elsewhere in this
document eliminates this possibility."
SEG determined that the failure of the heat removal system would result in a site boundary (100
meter) whole-body dose of less than 0.1 mrem and a thyroid dose of less than 0.3 mrem. SEG
estimated that essentially no release to the environment would occur as a result of the pressure
4-5
-------
excursion accident. For comparison, the following annual doses were calculated (again using
AIRDOSEPA) for routine operations.
Distance
(meters)
100
200
300
500
800
1300
1800
Whole Body Dose
(mrem)
2.3
1.2
0.8
0.5
0.4
0.3
0.26
Thyroid Dose
(mrem)
17
9
6
3.8
2.7
2.1
1.7
SEG noted that these doses fall well within the required EPA limits of 25 mrem/yr (whole body)
and 75 mrem/yr (critical organ), and are substantially below the approximately 120 mrem/yr
whole-body dose from natural background for that area.
4.1.2 Rocky Flats
In 1987 the Colorado Department of Health (CDH) prepared a preliminary public health risk
assessment for the radioactive component of proposed trial burns at the DOE Rocky Flats Plant
mixed waste fluidized bed incinerator (COL87). One maximum "credible" accident scenario and
one "incredible" accident scenario were analyzed. Both depleted uranium and weapons grade
plutonium were slated to be used in the trial burns. The proposed trial burns did not take place;
however, the following summaries from the Colorado assessment do provide an illustration of
the nature and consequences of potential accidents.
A Maximum Incinerator Trial Burn Credible Accident scenario, primarily based on the
overpressurization of the Fluidized Bed Incinerator system, was evaluated.
4-6
-------
The CDH report lists the following assumptions for this accident evaluation:
1 hour fueled fire release and 1 hour exposure to the plume; Pasquill Stability Factor
F (least dispersion)
low average wind speed of 3 meters/second (6.7 mph); 0 meter effective stack height
(low immediate dispersion)
- X/Q from "Workbook of Atmospheric Dispersion Estimates, 1969" (DHEW) for 1.2
miles, .0000833 seconds/cubic meter
- both radioactive materials are in both forms (liquid and solid) of mixed waste
no radioactive materials are retained in the ash
- overpressure route uses three HEPA stages (release fraction = 0.005 x 0.002 x
0.002 = 0.000 000 002)
- total 1 hour inventory is released over 1 hour and the exposure is for 1 hour for dose
calculation
there is no retention or plateout in the incinerator or ventilation equipment
a 70-year dose accumulation period for all organs after the time of an assumed
"acute" exposure
Class Y materials (cleared from the lung over a period greater than 1 year
a high breathing rate of 1.2 cubic meters per hour (28.8 cubic meters per day or 1.2
liters per minute)
The resulting 70-year committed dose equivalents for the impacted organs were in the range of
1 x 1O"9 rem or smaller. The overall individual lifetime risk for radiation-caused disease
resulting from this accident scenario was conservatively calculated to be one chance in 1.09 x
109. The CDH reported that with adjustments for conservatism, this risk would fall to one
chance in 1.53 x 1017.
The CDH evaluated an "incredible" Incinerator Trial Burn Accident scenario as one in which
the entire filtering system is non-functional (destroyed). The assumptions used to calculate the
4-7
-------
70-year organ dose commitments were stated to be basically the same as those noted above,
except that no credit was taken for any filtering. The doses calculated for a 1-hour feed rate
accident was in the range of 1.8 rem or smaller for this scenario. The overall individual lifetime
risk for radiation-caused disease from this scenario was conservatively calculated to be one
chance in 2.17 x 103. Adjusted for conservatism, this number was also said to fall to 1.53 x
10".
4.1.3 Duke Power Company
Duke Power Company analyzed four potential worst case accidents in its initial submittal to the
NRC for approval to operate its low-level waste incinerator (DUK85). Duke noted that the
choice of these accidents was made after the radiological consequences of a spectrum of potential
failure events were analyzed. Subsystems and components which might contain radioactive
materials in significant quantities were identified and separated for analysis purposes as follows:
- Contaminated oil storage and feed systems.
- Wet solids storage and feed system.
- Dry active waste storage and feed system.
- Fluid bed process vessels.
- Bed material storage and transfer hoppers.
- Scrubber preconcentrator and scrub liquor recirculation circuit.
- Product Storage Hopper.
- Process Filter/Adsorber Assembly.
These components were analyzed for accident consequences on the basis of presence of activity
alone. Duke states that attempts were made to postulate mechanisms by which releases could
originate, but that the main factor in choosing worst case accidents to be analyzed in detail was
the radiological consequence potential, independent of the likelihood of occurrence. Table 4-1
lists the activity releases (in Ci) assumed for these worst case accidents.
4-8
-------
Table 4-1. Activity Releases - Worst Case Accidents (Ci) Duke
Power Company Incinerator00
Carbon Adsorber Product Hopper
Nuclide Fire Rupture
w Source: DUK85
Exponential notation, 3.7(+l) means 3.7xlO+
Scrub Circuit Trash
Failure Fire
Total 0.9
H-3 0
C-14
Mn-54
Fe-55
Ni-59
Co-58
Co-60
Ni-63
Nb-94
Sr-90
Tc-99m
Tc-99
Mo-99
1-129 l.l(-3)
1-131 9.0(+0)
1-133 2.5(-2)
1-134 1.0(-3)
Cs-134
Cs-135
Cs-137 -
3.7(+l)w 1.4
4.0(-3)
7.2(-l)
8.4(-4)
1.0(+1) -
1.6(+0)
2.6(-l)
2.7(-5)
7.8(-3)
4.0(-2) -
3.4(-5)
4.4(-2)
1.1 (-4) 1.4(-6)
7.5(+0) 1.7(-1)
2.5(-2) 3.0(-3)
1.00-3) 8.5(-4)
5.9(+0)
3.4(-5)
2.2M,
2.4(-3)
8.8(-5)
\ s
4.8(-2)
5.7(-5)
9.6(-2)
\ y
1 Q ( £\
1 8(-4)
•• •
7.3(-7)
2.2(-6)
_
.
1.7(-2)
7.'5(-7)
2.5(-2)
4-9
-------
The four accidents selected for further analysis are as follows:
(1) The Process Gas Filter Assembly was analyzed because of the long term collection
of particulate activity on the HEPA filters and iodine on the carbon adsorber.
(2) The rupture of the Product Storage Hopper was analyzed due to the large amount of
high specific activity product ash collected within the hopper.
(3) The Scrubber Preconcentrator scrub liquor circuit failure was analyzed due to the
buildup of radioactive iodine which may recirculate in the scrub circuit.
(4) A fire involving the flammable contaminated trash was also analyzed since significant
volumes of these contaminated wastes may accumulate in storage areas prior to
incineration.
The following paragraphs excerpted from the Duke submittal to the NRC briefly describe each
postulated accident, how it would be detected, and its projected radiological consequences.
Process Gas Carbon Adsorber Release - This postulated accident involves the release of
iodine activity collected on the process gas carbon adsorber. A fire of undetermined
origin involving the process gas carbon adsorber is the postulated release mechanism.
High temperatures in the carbon bed would be detected by the operator who could initiate
the fire protection system as necessary. The loss of differential pressure across the
filter/adsorber assembly would also alert the operator to the accident.
It was conservatively assumed that all iodine activity input to the Volume Reduction
Subsystem is collected on the carbon adsorber and that the adsorber was in service for
6 months prior to the event. Credit for iodine decay was taken and a 95 percentile
4-10
-------
accident X/Q of 2.2X104 s/m3 was used in the dose analysis. The resulting whole-body
dose offsite for this event was calculated to be 1.9 mrem. The maximum organ dose was
found to be 1020 mrem to the thyroid of an individual breathing air (a maximum
individual breathing rate of 3.47 x 1O3 m3/s assumed in all accident inhalation doses
calculated) at the site boundary during the event.
Product Hopper Rupture - The rupture of a loaded Product Hopper would result in the
release of dry product ash to the surrounding cubicle. Ventilation systems serving the
cubicle could transport this ash to the outside environment; resulting in offsite exposure.
A Product Hopper rupture could result from natural phenomena, such as an earthquake,
or an overpressure transient from an undetermined source within the system.
The postulated causes (i.e., explosion or earthquake) of a Product Hopper rupture would
be readily detected by the operator at the onset of any such event; resulting in immediate
Volume Reduction System shutdown. In any case, where a rupture occurred unnoticed,
the operator would be alerted by high radioactivity concentrations in the HVAC exhaust
flow, hopper pressure change, and area monitors.
It was conservatively assumed.that 100 percent of the product ash contained in a fully
loaded hopper escapes unfiltered via the cubicle ventilation system. Worst case product
ash nuclide concentrations were calculated based on calcined concentrates with an
assumed volume reduction factor of 11. The resulting particulate plume was assumed
to be transported undepleted to the site boundary. The resulting maximum whole-body
dose offsite was calculated to be 85 mrem. The maximum organ dose was determined
to be 860 mrem to the thyroid of an individual breathing air at the site boundary during
the event.
Scrub Liquor Circuit Failure - The postulated failure of the preconcentrator scrub liquor
circuit would result in the spillage of concentrated liquid containing iodine. The concern
4-11
-------
here will be the evolution of gaseous radioactive iodines which could be transported
offsite in air. Any liquid released from the scrub circuit will be contained within the
facility and should not be available for transport in ground or surface waters offsite.
The release of the scrub inventory could result from a rupture of either the Scrubber
Preconcentrator vessel or recirculation piping.
The loss of a significant quantity of scrub liquor would result in the lowering of the scrub
liquor level in the Scrubber Preconcentrator sump. This would be noticed by the
operator. If no operator action is taken or the sump inventory is lost rapidly, the process
would automatically shutdown due to loss of fluid flow to the venturi.
It was assumed that all the scrub solution in the Scrubber Preconcentrator sump and
recirculation piping is spilled. Iodine recirculation and decay within the dryer/off-gas
loop is analyzed assuming an iodine DF of 2 for the dryer/cyclone. Maximum activity
releases are calculated for each isotope. The postulated release assumes 100 percent of
the calculated maximum buildup activity is available for transport offsite. The resulting
maximum whole-body dose offsite was calculated to be 0.04 mrem. The maximum
organ dose was determined to be 20 mrem to the thyroid of the individual breathing at
the site boundary during the event.
A groundwater transport analysis was also analyzed for this postulated worst case liquid
release event. The saprolite soil characteristic of the Oconee site is an effective barrier
to the migration of radionuclides. The movement of radionuclides released in this
postulated worst case event would be so extremely slow that concentrations resulting at
the nearest potable intake would be well below 10 CFR 20, Appendix B, Table II,
Column 2 maximum permissible concentration values.
4-12
-------
Trash Fire - A fire involving contaminated trash being stored prior to incineration would
result in offsite exposure from activity transported along with other combustion products
through the air. A fire could result from accidental causes.
Facility smoke detectors would ensure prompt detection of any fire in the storage areas.
The visible smoke resulting from a fire would provide a secondary means for detection
of this postulated accident.
It was conservatively assumed that as much as 80 cubic meters of contaminated trash
activity is released and transported offsite due to the fire. The resulting maximum
whole-body dose was calculated to be 0.3 mrem. The maximum organ dose was
determined to be 5.7 mrem to the bone of an individual breathing air at the site boundary
during the fire.
For comparison, the maximum total body (child) and critical organ (infant thyroid) doses for
airborne effluents from normal operations were calculated at 1.5 x 10'3 mrem/yr and 1.8 x 10'1
mrem/yr, respectively.
4-13
-------
Chapter 4 References
BER88 Bergman, W., "Review of Some Health and Safety Aspects of the
Planned for the LLNL Decontamination and Waste Treatment Facility (DWTF),
Safety Science Group, Special Projects Division, Hazards Control Department,
Lawrence Livermore National Laboratory, December 23, 1988.
COL87 Colorado Department of Health, Rocky Flats Plant Trial Burn Health.Risk
Assessment, by Letter of Thomas P. Looby, Assistant Director, Office of HeaWi
and Environmental Protection, to Dr. Jim Ruttenbur, Center for Disease Control,
June 30, 1987.
DUK85 Duke Power Company Transmittal, Request for Approval to Operate the Oconee
Nuclear Station Radioactive Waste Volume Reduction Incinerator, by Letter ol
Hal B Tucker, Vice President, Nuclear Production, to Harold R. Denton,
Director, Office of Nuclear Reactor Regulation, U. S. Nuclear Regulatory
Commission, June 10, 1985.
SEG88 Scientific Ecology Group Radioactive Waste Incinerator NESHAPS Permit
Application, Radioactive Material License Amendment Application, Air Pollution
Control Permit Application, May 19, 1988.
4-14
-------
5. Comparison of Incineration with Other Volume Reduction Technologies
A number of technologies and techniques are used to reduce the volume and radionuclide content
of solid waste. These techniques and technologies are often grouped into end-point, source, and
administrative control categories. End-point controls generally refer to technologies that reduce
the volume of solid waste after the waste has been accumulated. Incineration and compaction
are good examples of end-point techniques. Source controls emphasize reducing the volume of
waste at the point of generation. For example, segregating and decontamination/recycling of
wastes are source control techniques. Administrative controls are specific suggestions to
improve waste management operations and general housekeeping. Neat, organized, and well-
planned facilities and operations generate less waste. Advanced planning can reduce the amount
of unnecessary materials that enter radioactive areas and that become contaminated.
End-point controls include sorting, shredding, compaction, supercompaction, incineration, and
storage for decay.
Administrative and source control techniques include maximizing compactable drum weights,
landfill disposal of Below Regulatory Concern wastes, limiting access to radiation control areas,
decontamination and reuse of materials, and use of strippable coatings.
This chapter briefly reviews volume reduction factor (VRFs) associated with end-point control
technologies.
End-point volume reduction techniques are primarily applied to general trash, often referred to
as dry active waste (DAW) and consisting of a variety of materials that become contaminated
through normal operations. End-point volume reduction is best viewed as part of a process, not
the simple application of a technology. Figure 5-1 presents the overall flow of an example
process.
5-1
-------
Class A
Dry
Active
Waste
Non-radioactive
Waste
Shred
Sort
Combustible/
Compactible
Non-combustible/
Non-compactible
Compact
Incinerate
Immobilization
Solidification
Size Reduction
and
Decontamination
Non-radioactive
Waste
Radioactive
Waste
Storage/Burial
Figure 5-1. Volume Reduction Logical Process
5-2
-------
5.1 SORTING
As radioactive trash is generated, it usually receives some form of pretreatment, generally
consisting of sorting the material, such as separating combustible from noncombustible material,
prior to incineration or separating compactable from noncompactable material prior to
compaction. Hand sorting is the most direct method of segregating wastes into constituents that
are amenable to treatment by a particular technology, or into radioactive and nonradioactive
components.
Pneumatic sorting by an air or inert gas stream can also separate lower density combustible
materials, such as paper, plastic, and rags, from higher density noncombustible material such
as glass and metal. Manual sorting for radioactivity consists of using a sorting table where bags
with low radiation levels are segregated. Radiation readings used for this initial screening have
been reported as about 1 mrem/h for typical nuclear reactor facilities (NRC 81a). The contents
of these bags are opened, and the individual items are scanned and segregated. Automated trash
monitors that are more sensitive and reliable for segregating radioactive from nonradioactive
waste also are available (SHR 86; SNE 88). DAW volume deductions of 31 percent through
the use of a trash sorting table have been reported (SNE 88).
5.2 SHREDDING
Combustible and compactable materials are sometimes shredded to produce small pieces.
Shredding by itself yields some volume reduction because of the greater packaging efficiencies.
Shredding is also used to achieve improved performance of compactors and as a necessary
pretreatment for certain kinds of incinerators.
5.3 COMPACTION
Typical trash compactors, which are widely used throughout the nuclear industry, consist of a
mechanical or hydraulic ram that applies a compressive force of 430 to 2,100 psi and uses a
5-3
-------
standard 55-gallon drum as the compaction vessel. Standard compactors can potentially achieve
volume reduction factors up to 4 depending on the void volume and the resiliency of the trash.
However, the average reported volume reduction factor is 2. A shredder mated with a 1,270-psi
compactor has been developed that achieves a 50-percent greater volume reduction than a
compactor alone (NRG 81).
5.4 SUPERCOMPACTION
Supercompactors, which apply a force of about 8,000 psi, can achieve a 7-fold or greater
volume reduction factor for uncompacted dry active waste. If the waste has already been
compacted, supercompaction can achieve an additional 2to 4-fold volume reduction.
5.5 STORAGE FOR DECAY
Many radionuclides used by hospitals, universities, research facilities, and in some industrial
applications have relatively short half-lives that make it feasible to store radioactive waste for
decay. Typically, short-lived radionuclides that are stored for 10 half-lives can be considered
nonradioactive and disposed of as such. The passing of 10 half-lives reduces the radionuclide
content of the waste by a factor of 210 (or about a 1,000-fold reduction in radioactivity). It is
important to recognize, however, that a l,OOO-fold reduction in the radioactivity of waste does
not guarantee that the waste is suitable for disposal.
5.6 COMBUSTION
Most dry active waste and other forms of organic waste can be reduced in volume through
oxidation processes including incineration, pyrolysis, acid digestion, and molten salt combustion.
Incineration involves the burning of combustible materials in air or in an oxygen-rich
atmosphere. Pyrolysis is volatilization in an oxygen-deficient atmosphere that gasifies part of
the waste material. Acid digestion involves oxidation of materials by nitric acid in a
5-4
-------
concentrated sulfuric acid and nitric acid media. Molten salt combustion involves air oxidation
of combustible materials in a molten salt environment.
Table 5-1 summarizes volume reduction factors of the different types of technologies.
5-5
-------
Table 5-1. Volume reduction factors of selected technologies
Technology
Sorting
Drum Compactor
Box Compactor
Shredder/Compactor
Shredder/High-Pressure
Typical Use
Low-Level Waste
Low-Level Waste
Low-Level Waste
Low-Level Waste
Low-Level Waste
Volume
Reduction Factor
3
2
2.2
3.3
5.5
Compactor
Supercompactor
Compactor/Supercompactor
Storage for Decay
Pathological
Incinerator
Agitated
Hearth Incinerator
Controlled Air
Incinerator
Cyclone Drum
Incinerator
Rotary Kiln
Incinerator
Pyrolysis
Acid Digestion
Molten Salt
Combustion
Fluidized Bed
(Calciner)
Combustion
Low-Level Waste
Low-Level Waste
Short Half-life Waste
Institutional Trash,
Biowaste, Organic Liquids
Transuranic (TRU) trash
TRU, Low-Level Waste
Compacted TRU trash
Municipal Solid Waste,
Industrial Solid, Liquid,
and Gaseous Waste
TRU Waste
TRU Waste
Municipal Waste
and Chemical Wastes
Aqueous Waste, Shredded
Waste, Wet Solids
7.0
11.0
Potentially Very Large
Trash 20
Glass 4
Plastic > 100
Fluids > 100
Biowaste 15
Trash 40
Trash
Trash
40
43
Trash
23
Resins 18
Filter
Sludge 5
Evaporator
Bottoms 8
Trash 80
Prepared from References NRC 81 and NRC 8 la.
Denotes that the information was not provided in NRC 8 la.
5-6
-------
Chapter 5 References
NRC81 Nuclear Regulatory Commission; Data Base for Radioactive Waste Management
Waste Source Options Report. NUREG/CR-1759, November 1981.
NRCSla Nuclear Regulatory Commission; Volume Reduction Techniques in Low Level
Radioactive Waste Management. NUREG/CR-2206, September 1981.
SHR86
SNE88
Shriner, D.G. et al.; A Regional Approach to Determine Waste Segregation/Volume
Reduction Program. In "Waste Management'86". March 1986.
Snead, P.B. "Volume Reduction of Dry Active Waste by Use of a Waste Sorting
Table at the Brunswick Nuclear Power Plant" in Proceedings of the Tenth Annual
DOE Low-Level Waste Management Conference, CONF880839. December 1988.
5-7
-------
-------
6. Summary
6.1 REPORT OBJECTIVE
This report, consisting of Volume I - Technology, and Volume II - Risks of Radiation Exposure,
provides basic information on the technology and radiological risk associated with incineration
of radioactive and mixed wastes. The report is in response to a request from the State of New
Mexico to the US EPA Control Technology Center for basic information on incineration of
radioactive and mixed wastes. The approach to filling the request was to obtain information
from incinerator operators and describe the waste streams, off-gas emission control technology,
emissions monitoring principles and technology, emissions, and associated radiological risks.
It was recognized that the experience history of radioactive and mixed waste incineration
research, test, and evaluation is not as extensive as for hazardous waste incineration. As the
information gathering progressed, it also became apparent that there is a general absence of
operational data acquired in a consistent, methodical fashion that will allow direct correlations
between incinerated waste characteristics and stack radionuclide emissions. The causes for this
lack of usable data are related to waste management practice or incinerator/exhaust stack design.
6.2 INCINERATION
Incineration of combustible waste is a proven volume reduction technology. Comparisons with
several volume reduction methods are summarized below:
Compacting
Sorting
Shredding/Compacting
Supercompacting
Compacting/Supercompacting
Acid Digesting
Incinerating (Controlled Air)
Storing for Decay
Reduction Factor
2
3
3
7
11
23
40
Very Large
6-1
-------
A generic incineration flowsheet is shown in Figure 6-1. Some components, for example, "Feed
Preparation," "Feed Metering and Injection," and "Combustion," are essentially independent of
the waste contaminants; therefore, hazardous waste incineration experience with these
components is directly applicable to radioactive/mixed waste incineration. Hazardous waste
incineration "Ash Removal System," "Ash Disposal," "Offgas Cleanup System," "Residue
Treatment System," "Residue Disposal," and "Stack" experience is useful but less applicable.
Actual radioactive and mixed waste incineration data are required in order to fully describe the
effects of these components on radioactive effluents. Some pertinent characteristics of the three
incinerator types most commonly used or proposed for use with radioactive mixed wastes are
summarized below:
Rotary Kiln
Advantages
Advantages
Wide variety of liquids and solids
Accepts drums and bulk containers
High turbulence and air exposure
Can use wet gas scrubbing system
Residence time controlled by rotation
Simplified waste preparation
Temperatures to 2500eF
Disadvantages
High capital costs
Refractory damage
Possible incomplete combustion
High particulalo loading
Low thermal efficiency
Seal maintenance problems
Paniculate; in off-gas
Fluidized Bed
Solids, liquids, and gases
Accepts feed fluctuations
Relatively low acid gas formation
Lower cost emission control
Low maintenance costs
Enhanced combustion efficiency
Relatively low maintenance costs
Difficult to remove bed residuals
Bed preparation and maintenance
Relatively high operating costs
Eutectic formation
Difficult to feed irregular bulk waste
Select feed to avoid bed degradation
Controlled Air
Wide variety of solids, sludges
Long residence times
Low entrainment of ash
Complete combustion (multi-hearth)
Small fluctuations in offgas stream
Can use several fuels
High fuel efficiency
High maintenance costs
Refractory and hearth failure
Difficult to feed bulk wastes
Lower operating temperature
Slow temperature response
Difficult to control supplementary
fuel firing
6-2
-------
Waste Generation Activities
Waste Characterization
Radiological
Physical
Chemical
Non-
suitable
Wastes
Conditioning! Paniculate
1 Removal
t Gas
! Removal
Residue Treatment
System
Disposal
• Packaging
• Solidification
1 Characterization
1 Shipment
Laboratory Analysis
• Specific radionuclide
• Total Alpha
• Total Beta
• etc.
Figure 6-1. Generic Incineration Flowsheet
6-3
-------
The incinerators listed below provide the operating history of large volume radioactive/mixed
waste incineration in the U.S.
Los Alamos National Laboratory
Oak Ridge National Laboratory
Savannah River Site
Idaho National Engineering Lab
Rocky Flats Plant
Brookhaven National Laboratory
Scientific Ecology Group
Advanced Nuclear Fuels
DSSI
Duke Power Company
Commonwealth Edison Company
operable - awaiting EIS
operable - in test
shutdown for modification (B-G)
operating (WERF)
shutdown for modification
operable
operating
operating
permitting stage - operational 1991
lay-up (Oconee)
lay-up (Byron, Braidwood)
6.3 RELEVANT ISSUES
Several relevant issues regarding the incineration of radioactive and mixed waste are summarized
below. The reader is urged to refer to the respective sections of this report for more details.
A brief description of the major concerns are included for each issue.
6.3.1 Waste Acceptance Criteria
• The formulation of waste acceptance criteria is a necessary component in
establishing a quality control program designed to limit radioactive emissions and
offsite exposures.
• It should be recognized that DOE is in the process of revising its waste acceptance
criteria for low-level, TRU, and mixed wastes. Such activities have in part been
motivated by DOE's Environmental Restoration Plan, operational needs, and stricter
DOE Order guidelines. Accordingly, data characterizing past operational practices
may not always represent current or even future impacts.
6-4
-------
In establishing acceptance criteria, the radiological characterization of the waste
must address such considerations as:
List acceptable and nonacceptable radionuclides and establish a maximum
allowed concentration and quantity for each acceptable radionuclide.
Acceptability is dependent on the licensing conditions (i.e., DOE Orders), the
capability of the incinerator system to remove radionuclides from the offgas, the
limits of detection of the stack radionuclide monitoring system, and the offsite
release scenario.
Address the differences between volatile and nonvolatile radionuclides. The
behavior of radionuclides through the incineration process differs for readily
volatilized species such as iodine and nonvolatiles (refractories) such as
plutonium. Very volatile radionuclides, such as carbon and tritium, will not be
trapped by offgas systems and will escape in the stack effluent.
Detailed characterization of the waste is necessary to ensure that contaminant
concentrations do not exceed limits. Consider the halflife, decay, and initial
source quantity of each radionuclide. Waste may contain long-lived
radionuclides such as plutonium-239 and strontium-90 and short-lived
radionuclides such as iodine-131. For short-lived radionuclides, storage for
radioactive decay prior to incineration may be desirable since it may reduce
radioactivity to insignificant amounts.
Nuclear criticality is generally not a major concern, but should be addressed,
depending upon the presence of radionuclides such as plutonium and uranium.
Accumulation of such radionuclides in larger amounts in ashes and incinerator
components should be evaluated.
Acceptance criteria must also address the nonradiological characteristics of the
waste.
6-5
-------
Waste forms include liquids and solids with widely varying chemical/physical
properties, some of which may adversely affect incinerator components because
of their corrosive properties.
Low-level waste includes laboratory equipment and supplies, decontamination
debris, and miscellaneous solids and sludges.
Mixed waste may contain scintillation fluids, solvents, degreasers, lead, spent
filters, and soil.
Incinerators require consistent feed rate and content. Physical properties of the
waste, including Btu content and waste form, must be monitored to ensure
stable incinerator operating conditions.
The included low-level, TRU, and mixed waste characterization is based on
several compilations of data gathered by DOE over the past 4 years. The actual
distributions of waste volumes and properties may change because of DOE's
current activities associated with the Environmental Restoration Program.
Accordingly, the characterization and data summaries provide only a snapshot
description of low-level, TRU, and mixed waste generation, treatment, and
disposal activities at the given DOE facilities.
6.3.2 Incinerator Operations
Incinerators function best under strictly controlled, predictable, steady-state
conditions. Analysis and control of feed material to prevent fluctuating conditions
in the quantity, physical, and chemical waste characteristics are critical aspects of
operations.
6-6
-------
• Most problems encountered are associated with operational reliability and
maintenance. Problems typically include: frequent replacement of off-gas system
filters, corrosion of components, plugging of heat exchangers, incomplete
incineration, accumulation of residual ashes in systems and components not designed
for ash removal, personnel exposure, contamination control, fires in filter systems,
humidity control, and HEPA filter clogging.
• Incineration results in higher concentrations of radioactivity and higher radiation
levels in ash, when compared to the feed material. The majority of ash is collected
in the ash bin, however, small amounts are retained in other sections of the
incinerator system, creating potential removal and handling problems. Ash removal
and handling must be performed under radiologically controlled conditions. Some
of the major concerns associated with ash handling and disposal are occupational
radiation exposure and exposure to the public during transportation to disposal sites.
The TCLP toxicity test may result in ash designation as mixed or hazardous waste.
• System designs that include the merging of incinerator stack gas into a common
plenum with other effluent sources may preclude any meaningful interpretation of
effluent results. Such features make it difficult to resolve radionuclide emissions
from the incinerator. , ,
• Desirable incinerator operating characteristics for the destruction of hazardous
materials may be counter productive in minimizing some types of emissions. For
example, large residence times, normally required for the destruction of organic
compounds, may result in the greater formation of metal oxide fumes. Some
radionuclides, which volatilize at higher temperatures, may coalesce as particulates
at cooler temperatures with higher specific activity than the waste itself.
• Radioactive/mixed waste incinerators can achieve reliability, availability, and
maintainability factors similar to that experienced by hazardous waste incinerators.
6-7
-------
Batch mode or periodic operation and HEPA filter replacement or failures are
factors that adversely affect the achievement of such goals.
• Potential accident scenarios include fires and explosions, emission control systems
failures, transportation mishaps, and loss of essential utilities. Identification of
expected operational events and application of prevention/mitigation measures must
be based on specific design characteristics and operating practices.
6.3.3 Stack Monitoring
• The exhaust stream must be sampled representatively, i.e., isokinetically. The
sampling train design must include sample probe, sample collector or monitor,
flowrate meter, sampling pump, and electronic controls, such as audio/visual alarms
and shut-off systems, if needed.
• Analysis can be performed on a real-time basis by a dedicated monitoring system
with required measurement sensitivity, or conducted periodically by pulling a
sample and performing the analysis in a laboratory. Real-time system operation,
calibration, and maintenance must conform to QA/QC procedures for such systems.
Laboratory sample analysis must also be performed under radiological quality
assurance and control procedures.
• Monitoring systems using gross counting methods can provide information only on
composite activities; i.e., the sum total of the radioactivity retained on the collection
media integrated over the sampling duration period. Systems that use spectrometers
(alpha or gamma) have the capability to identify each radionuclide as a function of
time.
• Real-time radionuclide monitoring is inherently difficult. Some radionuclides,
including tritium and C-14, cannot be monitored in real-time. Areas of concern
6-8
-------
include radionuclide plateout, selection of proper sample collection media for
particulates and gases, radiation detector sensitivity, transient nature of releases,
detector response characteristics, proper equipment maintenance, and corrections for
background radioactivity.
• Off-the-shelf incinerator stack real-time monitors are not commercially available.
Several vendors and manufacturers have installed off-theshelf real-time monitors
originally designed for nuclear facilities. Many of such commercial systems are
readily adaptable to incinerator applications.
• Most of the relevant operating experience resides with DOE. Since most systems
are designed as one-of-a-kind, the potential range of application and technology
transfer are limited. DOE emissions data (required by NESHAPS) consist generally
of annual release quantities in curies, and do not correlate emissions versus waste
processing activities. NESHAPS does not require this type of reporting format
since NESHAPS is only concerned with offsite releases and public exposures.
6.3.4 Radiological Risk Assessment . • . .
• In conducting a risk assessment analysis, each step in the waste management process
(in this case incineration) must be identified and thoroughly characterized. This
characterization must typically consider waste forms and generation practices,
incinerator and facility parameters, and environmental factors or site features.
Every step of the process, from waste receipt to ash disposal and stack effluent
release, must then be analyzed for assessing the potential risks to workers and the
public, as well as environmental impacts.
• Radiological impact is waste stream specific and is based on expected waste volume,
radionuclide distributions, and waste forms for a given incinerator design and
operating practices.
6-9
-------
• A simple method with which to assess the radiological impacts associated with waste
management is given in Volume II of this report. The method allows one to devise
assess emissions, occupational exposures, and offsite doses and risks based on
generic or default radionuclide waste concentrations. This method is presented only
for illustrative purposes and is not intended to be used to conduct a formal risk
assessment analysis.
6.3.5 Airborne Radionuclide Emissions
• A review of past operating practices indicates that radionuclide emissions are
generally well below DOE standards and guidelines.
• Since all measurements are made at the point of release, radionuclide concentrations
at downwind receptor locations would be still lower than those observed at the
stack.
• DOE incinerator emissions are typically identical to their commercial counterparts,
with the exception of plutonium, americium, and uranium.
• Radionuclide emissions can be generally classified into two categories; short-lived
and long-lived. Short-lived radionuclides typically include H-3, C-14, P-32, S-35,
Cr-51, Mn-54, Fe-55, Co-57, Tc-99m, 1-125,1-131, etc. Long-lived radionuclides
include Tc-99, Cs-137, Sr90, Am-241, Pu-238, Pu-239, Pu-240, U-233, U-234, U-
238, etc.
• In general, yearly emissions of long-lived radionuclides are on the order of
10 microcuries or less. Short-lived radionuclides are, however, released, at times,
at higher activity levels.
6-10
-------
A comparison between radioactivity contained in waste feed and stack emissions
reveals that overall incinerator decontamination factors range from 1O+3 to 10+u
depending upon the type of offgas treatment system. This comparison includes all
radionuclides for which data were available except for H-3, C-14, and radioiodines.
A review of DOE and commercial incineration practices indicates that low-level
waste is incinerated in varying frequencies and volumes, and involve different waste
streams or forms, e.g., liquids, solids, etc. The data indicate that incineration
schedules typically reflect Operational needs rather than the imposition of regulatory
constraints or limits.
6-11
-------
-------
APPENDIX 1
NRC INCINERATION GUIDELINES FOR MATERIAL LICENSEES
These guidelines apply to noncommercial waste disposal, that is, incineration of a licensee's own
waste. NRC may request additional information regarding proposed commercial incinerators
as appropriate to assess adequately the potential impact on public health and safety and the
environment.
Specific NRC approval is not needed in order to incinerate certain exempted categories of
radioactive waste. For example, 10 CFR Section 20.306 provides that tritium and carbon-14
in low concentrations in liquid scintillation media and animal tissue (less than or equal to 0.05
microcuries of tritium or carbon-14 per gram of liquid scintillation medium or per gram of
animal tissue averaged over the weight of the entire animal) may be disposed of without regard
to radioactivity. This exemption does not relieve the applicant from complying with other local
requirements for the disposal of such waste.
The following information must be provided when applying to the NRC for a license to
incinerate waste requiring specific NRC approval.
1. The characteristics of the incinerator and the site must be submitted. This includes the
height of the stack, rated air flow, distance from incinerator to nearest air intake duct of
adjacent building, and location and distance to nearest unrestricted areas, residence,
school, hospital, etc.
2. The specific isotopes and the maximum amount of each isotope to be incinerated per burn
must be stated. For the combination of isotopes listed, calculations must be submitted
to demonstrate that the following conditions will be met:
A 1-1
-------
a. The gaseous effluent from the incinerator stack will not exceed the limits
specified for air in Appendix B, Table II, 10 CFR Part 20 when averaged over
a 24-hour period.
b. In order to be in compliance with the ALARA philosophy stated in 10 CPR
Section 20.1(c), the gaseous effluent from the incinerator stack should be a
fraction (less than 10 percent) of the limits specified for air in 10 CFR 20,
Appendix B, Table II, when averaged over a period of one year.
If more than one isotope is involved, the calculations must follow the "sum of ratios"
method in the note at the end of 10 CFR Part 20, Appendix B..
The method to be used to determine the concentration of radionuclides released, both as
airborne effluents, and as any liquid effluents from scrubbers, condensers, or associated
systems. , . : • . . • ,
The maximum number of burns to be performed in any one week and the maximum
number of burns per year must be stated. ,
The method for estimating the concentration of radioactive material remaining in the ash
residue must be described. The most conservative assumption must be used unless
scientific evidence to the contrary is presented.
The procedures for collection, handling, and disposal of the ash residue, including
radiation safety precautions to be observed, must be described.
The procedures to be followed to minimize exposure to personnel during all phases of
the operation, including instructions given to personnel handling the combustibles and the
ash, must be described.
A 1-2
-------
7.
a.
b.
Any State or local permits which are required to operate an incinerator must be
identified. Evidence that such permits have been obtained must be submitted.
State and local government agencies should be notified early of plans to incinerate
radioactive waste, because they often must respond to inquiries from local citizens
and organizations. It is preferable that the applicant make such notifications and
obtain comments since the applicant is closer to the community. Indication that
such notifications have been made can be done by including copies of letters to
State and local government agencies and their comments with the application. If
the applicant does not notify State and local governments, the NRC will do so
directly.
A 1-3
-------
-------
APPENDIX 2
NUCLEAR REGULATORY COMMISSION OUTLINE FOR SAFETY RELATED TOPICS
DESIGN AND OPERATION OF LOW-LEVEL RADIOACTIVE WASTE INCINERATOR
I. PRINCIPAL DESIGN CRITERIA
a. Purpose of Incinerator Program
Incinerator feed
Incinerator products and byproducts
Incinerator functions
b. Structural and Mechanical Safety
c. Safety Protection Systems
Confinement barriers and systems
Off-gas treatment and ventilation
Controls and instrumentation
Nuclear criticality safety
Radiation protection
Fire and explosion
Feed and product handling and storage
Decommissioning
II. FACILITY DESIGN
a. Summary Description
Location and facility layout
Principal features
b. Incinerator Building
Structural specifications
Building layout
Incinerator description
c. Support Systems
Support requirements
Support systems descriptions
d. Service and Utility Systems
Building ventilation
Incinerator fuel
Utilities, electrical, steam, water, etc.
Safety communications and alarms
Fire protection
Maintenance
III. PROCESS SYSTEMS
a. Process Description
Narrative
Flow diagrams and sheets
b. Process Chemistry and Physical and
Chemical Properties
c. Mechanical Process Systems
d. Waste receiving, storage, and handling,
waste feeding; Product handling,
packaging, and storage
e. Chemical Process Systems
Incineration
- trash,
- resins,
- liquids,
- others
f. Process Support Systems
Instrumentation and control
Maintenance and repair
g. Waste Feed, Product, and Byproduct
Analyses
IV. PROCESS CONFINEMENT AND
MANAGEMENT
a. Ventilation and Off-gas Treatment
A 2-1
-------
Waste feed ventilation
Incinerator ventilation
b. Off-gas Treatment
Equipment and system description
Operating characteristics
Operating procedures
c. Product Handling Ventilation
d. Product Handling, Packaging, and
Storage
Equipment and system description
Characteristics, concentrations, and
volumes
Packaging
Storage
e. Effluent Sampling and Monitoring
f. Airborne
g. Liquid
V. RADIATION PROTECTION
a. Radiation Sources
b. Radiation Protection Design Features
Facility design
Shielding
Ventilation
Area radiation monitoring
Airborne radioactivity monitoring
VI. ALARA Program
a. Design considerations
b. Operational considerations
A 2-2
-------
APPENDIX 3
EXCERPTS FROM ILLINOIS REGULATIONS
Section 340.1060 Concentration of Radioactivity in Effluents to Unrestricted Areas
a) A licensee or registrant shall not possess, use, or transfer licensed material so as to
release to an unrestricted area radioactive material in concentrations which exceed the
limits specified in Appendix A, Table II, of this Part, except as authorized pursuant to
Sections 340.3020 or 340.1060(b). For purposes of Section 340.1060, concentrations
may be averaged over a period of not greater than 1 year.
b) An application for a license or amendment may include proposed limits higher than
those specified in Section 340.1060(a). The Department will approve the proposed
limits if the applicant demonstrates:
1) that the applicant has made a reasonable effort to minimize the radioactivity
contained in effluents to unrestricted areas; and
2) that it is not likely that radioactive material discharged in the effluent would
result in the exposure of an individual to concentrations of radioactive material
in air or water exceeding the limits specified in Appendix A, Table II, of this
Part.
c) An application for higher limits pursuant to Section 340.1060(b) shall include
information demonstrating that the applicant has made a reasonable effort to minimize
the radioactivity discharged in effluents to unrestricted areas, and shall include, as
pertinent:
1) information as to flow rates, total volume of effluent, peak concentrations of
each radionuclide in the effluent, and concentration of each radionuclide in the
effluent averaged over a period of 1 year at the point where the effluent leaves
a stack, tube, pipe, or similar conduit;
2) a description of the properties of the effluents, including:
A) chemical composition,
B) physical characteristics, including suspended solids content in liquid
effluents, and nature of gas or aerosol for air effluents,
C) the hydrogen ion concentrations (Ph) of liquid effluents; and,
A 3-1
-------
D) the size range of particulates in effluents released into air;
3) a description of the anticipated human occupancy in the unrestricted area
where the highest concentration of radioactive material from the effluent is
expected, and in the case of a river or stream, a description of water uses
downstream from the point of release of the effluent;
4) information as to the highest concentration of each radionuclide in an
unrestricted area, including anticipated concentrations averaged over a period
of 1 year:
A) in air at any point of human occupancy, or
B) in water at points of use downstream from the point of release of the
effluent;
5) the background concentration of radionuclides in the receiving river or stream
prior to the release of liquid effluent;
6) a description of the environmental monitoring equipment, including sensitivity
of the system, and procedures and calculations to determine concentrations of
radionuclides in the unrestricted area and possible reconcentrations of
radionuclides; and
7) a description of the waste treatment facilities and procedures used to reduce
the concentration of radionuclides in effluents prior to their release.
d) For the purposes of Section 340.1060, the concentration limits in Appendix A,
Table II, of this Part shall apply at the boundary of the restricted area. The
concentration of radioactive material discharged through a stack, pipe, or similar
conduit may be determined with respect to the point where the material leaves the
conduit. If the conduit discharges within the restricted area, the concentration at the
boundary may be determined by applying appropriate factors for dilution, dispersion,
or decay between the point of discharge and the boundary.
e) In addition to limiting concentrations in effluent streams, the Department may limit
quantities of radioactive material released in air or water during a specified period of
time if it appears that the daily intake of radioactive material from air, water, or food
by a suitable sample of an exposed population group, averaged over a period not
exceeding 1 year, would otherwise exceed the daily intake resulting from continuous
exposure to air or water containing one-third (1/3) the concentration of radioactive
material specified in Appendix A, Table II, of this Part.
A 3-2
-------
f) The provisions of Section 340.1060 do not apply to disposal of radioactive material
into sanitary sewage systems, which is governed by Section 340.3030.
g) In addition to the other requirements of this Part, licensees or registrants engaged in
uranium fuel cycle operations shall also comply with the provisions of 40 CFR 190,
"Environmental Radiation Protection Standard for Nuclear Power Operations," revised
as of July 1, 1984, exclusive of subsequent amendments or editions.
(Source: Amended at 10 111. Reg. 17538, effective September 25, 1986)
Section 340.3020 Method of Obtaining Approval of Proposed Disposal Procedures
a) Any person may apply to the Department for approval of proposed procedures to
dispose of radioactive material in a manner not otherwise authorized in this part.
Each application shall include a description of the radioactive material, including the
quantities and kinds of radioactive material and levels of radioactivity involved, and
the proposed manner and conditions of disposal. The application, where appropriate,
should also include an analysis and evaluation of pertinent information as to the nature
of the environment, including topographical, geological, meteorological, and
hydrological characteristics; usage of ground and surface waters in the general area;
the nature and location of other potentially affected facilities; and procedures to be
observed to minimize the risk of unexpected or hazardous exposures.
b) The Department will not approve any application for a license to receive radioactive
material from other persons for disposal on land not owned by a State or the Federal
Government.
(Source: Amended to 10 111. Reg. 17538, effective September 25, 11986)
Section 340.3050 Disposal by Incineration
No licensee or registrant shall incinerate radioactive material for the purpose of disposal or
preparation for disposal except as specifically approved by the Department pursuant to
Sections 340.1060 and 340.3020.
(Source: Amended at 10 111. Reg. 17538, effective September 25, 1986)
A 3-3
-------
Note: Following are selected pages from Section 340, Appendix A
§340.APR.A
SECTION 340. APPENDIX A
CONCENTRATION IN AIR AND WATER ABOVE NATURA1 BACKGROUND
Element
(atomic
number)
Actinium (89)
Americium (95)
Antimony (51)
Argon (18)
Arsenic (33)
Astatine (85)
Isotope1
Ac-227 S
I
Ac-228 S
I
Am-241 S
I
Am-242m S
I
Am-242 S
I
Am-243 S
I
Am-244 S
I
Sb-122 S
I
Sb-124 S
I
Sb-125 S
I
Ar-37 Sub2
Ar-41 Sub
As-73 S
I
As-74 S
I
As-76 S
I
As-77 S
I
At-211 S
I
Table I
Column 1 Column 2
Air Water
(uCi/mn (uCi/ml)
2X10-12
sxio"!1
** *' * Q
8X10-°
2X10"b
6X10-12
1x10-1°
6X10 10
3X10-1°
4X10-°
5X10-°
6X10 10
1x10-1°
4X10'°
2X10-3
2X10-7
1X10l7
2X10-8
5X10-7
3X10-8
6X10'3.
2X10'6
2X10-5
4X10l7
ixio-7
ixio-;
1X10-7
5X10-7
4X1Q-7
7X10-3
3X10-b
6X10-5
9X10-3
3X10-3
3X10-3
8X10'4,
1X10-5
3X1Q-3
4X10-3
4X10-3
mo:4,
ixio-}
1X10'1
8X10-^
7x10-5
7X10-5
3X10-3
3X10-3
lAlU -
2X10-3
2X1Q-J
6X10-5
2X10-3
2X10-3
2X10'3
Table I
I
Column 1 , Column 2
Air Water
(uCi/ml) (uCi/ml)
9X10-J3
3X10-3
6X10-10
2X10-13
4X10-}2
2X1Q-J3
2X10-3
2X10-}3
4X10'^
1X10-7
8X10"7
6X10-3
5X10-3
5X10-3
7X10-1°
2X10-°
9X10-10
lxlo"s
4X10"b
7X10-8
4X10-3
4X10-3
3X10-3
2X10-°
1X10-8
2X10-1°
!X10"y
«}•:!
9X10'^
9X10-=
3X10'^
4X10-°
9X10'=
4X10-^
3X10'=
5X10-3
3X10-f
3X10'=
2X10"=
2X10"J
5X10-1
5X10-4
5X10"=
5X10'=
2X10-5
8X10-=
8X10-=
7X10-5
340-39
January, 1987
A 3-4
-------
§340.APR.A
C 1 Aff*t**M-fc>
t lement
(atomic
number)
Californium (98)
Carbon (6)
Cerium (58)
Cesium (55)
Chlorine (17)
» i 1
Isotope1
Cf-249 S
I
Cf-250 S
I
Cf-251 S
I
Cf-252 S
I
Cf-253 S
I
Cf-254 S
I
(Co2) Sub2
Ce-141 S
I
Ce-143 S
I
Ce-144 S
I
Cs-131 S
I
Cs-134m S
I
Cs-134 S
I
Cs-135 S
I
Cs-136 S
I
Cs-137 S
I
Cl-36 S
I
Cl-38 S
I
Table ]
Column 1
Air
fuCi/ml)
2X10-}2
1x10-}°
5X10-}2
1X10-}°
2X10-}2
1x10-}°
6X10-}2
3X10-}*
8X10-}°
8X10-}°
5X10-}2
5X10-12
4X10'f
5X10"b
4X10"7
2X1Q-;
3X10-7
2X10
ixio-f
6X10-9
ixio-f
3X10"°
4X10'f
£ V 1 rt ™O
0/k Xu
4X10-8
IXIO"8
5X10"
9X10"?
4X10-;
2X10-7
6X10"f
1X10"8
4X10-7
2X10-°
3X10"°
2X10-6
r
Column 2
Water
(uCi/ml)
1X10-4
4X10-4
7X10-4
1X10-4
8X10-4
2X1Q-4
2X10-4
4X10-3
4X10'°
4X10'6
2X10-2
3X10-3
3X10-3
1X10-3
1X10-3
3X10-4
3X10-4
7X10'2
3X10-2
2X10-J
3X10'2
3X10-4
1X10-3
3X10-3
7X10-3
2X10-3
2X10-3
4X1Q-;
1X10-3
2X10-3
2X10-3
1X10-2
IXIO'2
Table I
Column 1
Air
(uCi/mlV
5X10-}4
3X10- 2
2X10-}3
3X10- j2
3X10- }2
2X10-J3
ixio-}2
3X10"11
11
3X10"l3
2X10-13
1X10-7
1 Yin~°
XA XU
5X1Q-9
9X10-9
7X10-9
3X10-10
2X10-10
4X10-7
1X10-7
1X10-°
2X10-;
1X10-9
4X10-J°
2X10'°
3X10-9
6X10-9
2X10"9
5X10-10
1X10"?.
8X1Q-J0
9X10-f
7X10'8
I
Column 2
Water
4X10-6
2X10-f
ixio-f
3X10-f
4X10"6
3X10-f
7X10-f
7X10-°
1X10-4
1X10-7
IXIO'7
8X10-4
9X10"5
9X10"5
4X10"f
4X10"5
1X1Q-5
IX ID'5
2X10"3
9X10*4
6X10-3
1X10*3
4X10"5
1X10-4
2X10"4
6X10-|
4X10-5
8X10"^
6X10-5
4X10-4
4X10-4
340-41
January, 1987
A 3-5
-------
§340.APP.A
—
Element
(atomic
number)
Gold (79)
Hafnium (72)
Holmlum (67)
Hydrogen (1)
Indium (49)
Iodine (53)
Isotope1
Au-195 S
I
Au-196 S
I
Au-198 S
I
Au-199 S
I
Hf-181 S
I
Ho-166 S
I
H-3 S
I
Sub2
In-113m S
I
In-114m S
I
In-115m S
I
In-115 S
I
1-125 S
I
1-126 S
I
1-129 S
I
1-131 S
I
1-132 S
I
1-133 S
I
1-134 S
I
1-135 S
I
Table
Column J
A1r
fuCI/ml]
8X10-6
6X10'°
6X10-7
3X10-;
2X10"'
1X10'°
8X10-'
4X10*3
2X10-7
2X10-7
SXlO'f
5X10"°
o\/i rt** J
2X10
8X10-?
7X10'°
1X10-7
2X10"°
2X10'°
2X10*°
2X10-7
3X10*8
5X10-9
8X10*9
3X10*7
2X10*5
7X10"°
9X10"5
3X10-7
2X10";
9X10"'
» »»»» Q
3X10-°
2X10"'
5X10*'
3X10'°
1X10-7
4X1Q-'
I
L Column 2
Water
i (uCi/ml)
4X10-2
6X10-3
5X10-3
4X10-3
2X10"J
IXIO-*
5X10-;*
4X10-3
2X10-3
2X10-3
9X10'4
9X10'4
ixio-}
IXIO'1
4X10-2
4X10**
5X10*5
5X10*4
1X10-2
3X10-3
6X10-3
5X10-=
3X10*3
6X10-3
6X10-5
2X10-3
2X10-3
5X10*3
2X10*4
2X10"2
7X10-4
Table II
Column 1 (
A1r
fuCi/ml) I
3X10-7
4X10-8
2X10-°
8X10-9
4X10-°
3X10"°
3X10-5
7X10-5
6X10-y
2X10-7
2X10*7
/I V 1 rt— 3
3X10-7
2X10"'
4X10 -y
7X10-J0
8X10-°
6X10-°
9X10-5
8X10'11
6X10"y
9X10-J1
2X10-J1
2X10-5Q
3X10-9
3X10 in
4X10- J°
7X10-5
6X10%
1X10-7
1X10-5
ixio-8
:olumn 2
Water
fuCi/ml)
IXIO'3
2x10-;
2X10-1
lxl°Is
2X10-4
2X10'4
7X10-5
3XlO-f
3X10'=
3X10-3
2X10-5
2X10-=
4X10-4
4xio':
9X10-=
9X10"=
2X10-7
2X10-;
3X10-'
9X10-=
6X10-8
2X10-4
3X10-'
6X10-=
8X10-°
4X10-5
4X10-6
7X10-=
340-44
January, 1987
A 3-6
-------
§340.APR.A
Element
(atomic
number)
Molybdenum (42)
Neodymium (60)
Neptunium (93)
Nickel (28)
Niobium (41)
)smium (76)
'alladium (46)
Isotope*
Mo-99 S
I
Nd-144 S
I
Nd-147 S
I
Nd-149 S
I
Np-237 S
I
Np-239 S
I
Ni-59 S
I
Ni-63 S
I
Ni-65 S
I
Nb-93m S
I
Nb-95 S
I
Nb-97 S
I
Os-185 S
I
Os-191m S
I
Os-191 S
I
Os-193 S
I
Pd-103 S
I
Pd-109 S
I
Table I
Column 1 Column 2
Air Water
(uCi/ml) (uCi/nfn
7X10-7
2X10'7
8x10-11
3X10-1°
4X10-;
2X10'7
2X10-°
ixio-°
4X1Q-J2
!X10-±°
8X10-;
7X10-7
5X10-7
8X10-7
6X10-?
3X10-;
9X10-;
5X10-7
1X10-7
2X10-;
5X10-7
mo'7
6X10'°
5X10-°
5X10-7
5X10-?
2X10
9X1Q-6,
4X10-7
4X10";
3X10-7
IXlO'f
7X10'7
6X1Q-;
4X10'7
5XKT3
IXIO-3
'2X10-3
2X10-3
2X10-3
8X10-3
8X10-3
9X10*5
9X10"4
4X10
4X10"3
6X10-3
6X10-2
8X10
2X10*2
4X10"3
3X10-3
IXIO-2
IXIO'2
3X10~3
3X10-3
3X10-2
3X10-2
2X10-3
2X10-3
7X10-2
7X10-2
5X10-3
5X10-3
2X10-3
2X10*3
1X10-2
8X10"
3X10-3.
2X10-3
Table
Column 1
Air
(uCi/ml)
3X10'8
7X10-9
3X10-12
1X10-1!
1X10"
8X10-|
6X10-°
5X10-8
1X10-J3
4X10-12
3X10-°
2X1Q-8
2X10'8
3X10'°
2X10-^
IXIO-8
3X10'8
o
2X10-8
4X10-9
5X10-9
2X10'°
3X10-9
2X10-;
2X10'7
2X10'8
2X10'9
6X10-;
3X10-;
4X10'8
IXlO'f
IXlO'f
9X10'9
5X10-8
3X10-°
2X10-f
IX 10'8
II
Column 2
Water
(uCi/ml)
,2X10-4
4XKT5
7X10'f
8X10-5
6X10"5
6X10"5
3X10"4
3X10'4
3xlo-6
3X10-5
ixio-4
2X10'4
2X10-3
C
3X10-5
7X10'4
ixio-4
4X10-4
4X10-4
ixio-4
IXIO'4
9X10"4
9X10"4
7X10-5
7X10-f
3X10-3
2X10-3
2X10";
2X10-J
6X10-5
5X10'5
3X10-4
3X10-4
9X10-5
7X10-5
340-46
January, 1987
A 3-7
-------
§340.APR.A
Element
(atomic
number)
Phosphorus (15)
Platinum (78)
Plutonium (94)
Polonium (84)
Potassium (19)
Praseodymium (59)
Promethium (61)
Isotope1
P-32 S
I
Pt-191 S
I
Pt-193m S
I
Pt-193 S
I
Pt-197m S
I
Pt-197 S
I
Pu-238 S
I
Pu-239 S
I
Pu-240 S
I
Pu-241 S
I
Pu-242 S
I
Pu-243 S
I
Pu-244 S
I
Po-210 S
I
K-42 S
I
Pr-142 S
I
Pr-143 S
I
Pm-147 S
I
Pm-149 S
I
Table
Column 1
Air
7X10-8
8X10"b
6X1Q-7.
7X10-°
5X10-°
3X1Q-7
6X10-°
5X10'°
8X10-;
6X10'7
2X10" 12
3X1Q-JJ
2X10- }2
4X10" JJ
2XlQ-|f
4X10-"
9X10-J1
4X10-°2
4X10"11
2X10-°
2X10-°,
2X10- }Z
3X10-11
5X10-j°
2X10- 10
2X1Q-?
1X10'7
2X10'7
3XKT7
2X10-7
6X10-8
1X10'7
3X10-7
2X10''
I
Column 2
Water
fud/ml)
5X1Q-4
4X1Q-3
3X10-3
3X10-2
3X10-2
3X10-2
5X10-2
3X10-2
3X10-2
4X10-^
3X10"J
8X10-4
1X10-5
8X10*5
1X10-5
8X1Q-;
7X10-J
4X10-2
ixio-J
9X1Q-^
1X10-2
1X10-2
1X10-5
3X10'4
2X10J
6X10"4
9X10-5
9X1Q-Z
1X10'^
1X1Q--3
6XKT3.
6X10-^
1X10"^
Table II
Column 1 Column 2
Air Water
(uC1/mn (uCi/ml)
2X10-9
3X1Q-9
3X10-8
2X10'°
2X1Q-;
2X10-7
4X10-°
2X1Q-7
2X10-7
3X10-°
2X10'S
7X10-}4
6X10Il2
6X10-J5
1X10-J2
3X10-J2
1X10-9
6X10-J2
1X1Q~¥
6X10-°
8X10"°4
1X10'12
2X10Il2
7X10-8
7X10-9
5X10-9
6X10-9
2X10-9
3X10Is
8X10"9
2X10'5
IXIO'5
1X10-5
1X10'^
1X10 *
9x10-5
2X10-3
1X10"^
9x10";
1x10-5
1X10'4
5X10'^
3X10'=
5X10"^
3X10'=
5X10-°
3X10'=
2X10-5
IXIO'J
5X10-°
** W 1 l*"> ™ J
3X10 =
3x10 :
3X10'4
mo-5
7X10"7
3X10"=
2X10'5
3X10-5
3X10-J
5X10'=
5X10'5
2X10-J
2X10"J
4X10'=
4X10'=
340-47
January, 1987
A 3-8
-------
§340.APR.A
Element Isotope*
(atomic
number)
Sr-90 S
I
Sr-91 S
I
Sr-92 S
I
Sulfur (16) S-35 S
I
Tantalum (73) Ta-182 S
I
Technetium (43) Tc-96m S
I
Tc-96 S
I
Tc-97m S
I
Tc-97 S
I
Tc-99m S
I
Tc-99 S
I
Fellurium j(52) Te-125m S
I
Te-127m S
I
Te-127 S
I
Te-129m S
I
Te-129 S
I
Te-131m S
I
Te-132 S
I
erbium (65) Tb-160 S
I
Table I
Column 1 Column 2
A1r Water
(uCi/ml) (uCi/ml)
IXIO-9
5X10-9
4X10-;
3X10-;
4X10-;
3X10"7
3X10-7
3X10-7
4X10-8
2X10'8
8X10-5
3X10"!
6X10-;
2X10-7
2X10-°
2X10-7
1X10-5
3X10-7
4X10-5
1X10
2X10-f
6X10'8
4X10-7
1X10-7
4X10-f
2X10-°
9X10-7
8X10"8
3X10-?
5X10-°
M W 1 rt*"O
ttX 1 IJ
4X10-7
2X10-;
2X10*;
IXIO-7
1X10-7
3X1Q-8
340-50
A 3-9
1X10-5
1X10"
2X10-3
2X10-3
2X10-3
2X10-3
8X10-3
1X10-3
IXIO-3
4X10*}
3X10- \
3X10-3
1X10
1X10"2
5X10-3
5X10-2
2X10-f
2X10'1.
8X10-2
1X10-2
5X10-3
5X10*3
3X10-3
2X10-3
2X10-3
8X10-3
5X10-3
1X10-3
6X10
2X10-2
2X10-2
2X10-3
1X10-3
9X10*7
6X10-4
1X10-3
ixio-J
Table II
Column 1
A1r
(uC1/mn
3X10-}*
2X10"
2X10-8
9X10-9
2X10-8
IXIO-8
9X10-9
9X10-9
1X10-9
7X10-*°
3X10'f
ixio-°
2X10-8
8X10"
8X10-8
5X10-9
4X10-7
ixio-|
5X10-7
7X10-f
2X10'9
IXIO-8
4X10-9
5X10-9
1X10-9
6X10-8
3X10-8
3X10-9
1X10-9
2X1Q-;
1X1Q-;
IXlO-f
6X10-9
7X10"9
4X10-9
3X10-9
IXIO-9
Column 2
Water
(uCi/mlV
3X10-7
4X10"5
7X10-f
5X10-5
7X10-5
6X10-5
6X10-5
3X10-4
4X10-5
4X10-5
1X10-2
1X10-2
ixio-4
4X10"4
2X10-3
8X10"4
j
6X10*3
3X10-3
3X10-4
2X10'4
2X10"4
ixio-4
6X10-5
5X10-5
3X10-4
2X10-4
3X10-5
2X10-5
8X10-4
6X10-5
4X10-5
3X10-5
2X10-5
4X10-f
4X10-5
January, 1987
-------
§340.APR.A
Element
(atomic
Uranium (92)
Vanadium (23)
Xenon (54)
Ytterbium (70)
Yttrium (39)
Isotope
U-230 S
I
U-232 S
I
U-233 S
I.
U-234 S4
I.
U-235 S4
I
U-236 S
U-238 S4
I
U-240 S
I
U-nat- A
ural S4
I
V-48 S
I
•)
Xe-131m Sub*
Xe-133 Sub
Xe-133ra Sub
Xe-135 Sub
Yb-175 S
I
Y-88 S
I
Y-90 S
j
Y-91m S
I
Y-91 S
I
Y-92 S
I
Y-93 S
I
Table I
Column 1
Air
(uCi/ml)
3X10-JO
1X10 10
3X10-J1
5X10-JO
ixio- JJ
6X10-J°
mo-jo
5X10-Jg
1x10-}°
6X10-JO
7X1Q-J1
1x10-1°
2X1Q-;
2X10'7
ixio-jo
ixio-10
2X10-J
6X10"8
2X10 g
1X10 c
1X10 j:
4X10
6X1Q-7
3X10-J
5X10-°
1X10l7
2X10-5
2X10-5
4X10-°
3X10'°
3X10-7
2X10%
1X10-'
Column 2
Water
(uCi/ml)
mjrj
8X10-}
8X10-}
9X10-}
9X10-}
9X10-}
9X10-}
8X1Q-}
8X10-4
1X10-3
1X10-*
lAiU _
1X10-3
IXIO-3
1X10-3
IXIO-3
9X10-}
8X10"4
3X1Q-3
2X10-3
3X10-^
6X10-}
6X10"4
ixio-}
IXIO'J
8X10"}
8X1Q-4
2X10-3
2X10-3
8X10'}
8X10'4
Table II
Column 1
Air
(uCi/ml)
ixio-ij
4X10-J2
3X10 1*
9X1Q-JJ
4X10-12
2X10-}1
4X1Q-J^
4X10"12
4X10-12
SXIQ-J*
5X10 _
6X10"9
5X10- J|
6X10-9
2X10"y
4X10~7
_.,1n-7
•^YlO'7
i vin-7
IxiS-S
6X10-5
2X10-y
4X10-y
3X10";
8X1Q-;
6X10-7
5X10-9
Column 2
Water
(uCi/ml)
5X10'^
3X10'^
3X10'5
3X10-5
3X10-=
3X10-5
3X10"^
3X10-5
4X10-5
4X10 ,.
3X10-5
3X10-5
3X10'b
3X10-5
ixio-}
IXIO'4
7X10"5
9X10"5
2X10-=
3X10-3
3X10-5
6X10-5
6X10-5
3X10"|
340-52
January, 1987
A 3-10
-------
§340.APP.A
n — — — • •*-
Element
(atomic
number)
Zinc (30)
Zirconium (40)
Any single radio-
• .
Isotope
Zn-65
Zn-69m
Zn-69
Zr-93
Zr-95
Zr-97
1
i*
S
I
S
I
S
I
S
I
S
I
S
I
Sub2
Table I
Column 1
Air
(ud/ml)
1X10-7
6X10-8
4X10-;
3X10
7X10'1
9XKT6
3X10-7
1X10-7
3X10-°
1X10-7
9X10-8
1X10'6
Column 2
Water
(uCi/ml)
3X10-3
5X10-|
2X10-3
2X10-3
5X10-2
5X10-2
2X10-2
2X10-2
2X10-3
2X10-3
5X10'4
5X10-4
Table I
Column 1
Air
(uCi/ml)
4X10"9
2X10-9
1X10-8
1X10*8
2X10-7
3X10-7
4X10-9
1X10-°
Q
4X10-9
4X10-9
3X10-9
3X10"8
I
Column 2
Water
(uCi/ml)
2X10'4
7X10"5
6X10"5
2X10-3
2X10-3
8X10-4
6X10-5
6X10"5
2X10-5
2X10-5
nucllde not listed
above with decay
mode other than
alpha emission or
spontaneous fission
and with radioactive
half-life less than
2 hours.
Any single radlo-
nucllde not listed
above with decay
mode other than
alpha emission or
spontaneous fission
and with radioactive
half-life greater than
2 hours.
Any single radlo-
nuclide not listed
above, which decays
by alpha emission or
spontaneous fission.
3X10
-9
9X10
-5
6X10
-13
1X10
-10
3X10
-6
4X10-7 2X10'14 3X10'8
Soluble (S); Insoluble (I),
340-53
A 3-11
January, 1987
-------
§340.APP.A
2 "Sub" means that values given are for submersion in a semi-spherical
infinite cloud of airborne material.
3 These radon concentrations are appropriate for protection from radon-222
combined with Its short-lived daughters. Alternatively, the value in Table I
may be replaced by one-third (1/3) "working level-. (A "working eve ' is
defined as any combination of short-lived radon-222 daughters, polomum-218,
I«d3l4, bismuth-214, and polonium-214, in 1 liter of air, without regard to
the degree of equilibrium, that will result in the ultimate emission of 1.3 X
10§ MeV of alpha particle energy.) The Table II value may be replaced by one
thirtieth (1/30) of a "working level". The limit on radon-222 concentrations
in restricted areas may be based on an annual average.
4 For soluble mixtures of U-238, U-234 and U-235 in air, chemical toxicity may
be the limiting factor. If the percent by weight (enrichment ) of U-235 is
less than 5, the concentration value for a 40-hour workweek, Table I, is 0.2
milUqrams uranium per cubic meter of air average. For any enrichment, the
product of the average concentration and time of exposure during a 40-hour
workweek shall not exceed 8 X 10'3 SA uC1-hr/ml, where SA is the specific
activity of the uranium inhaled. The concentration value for Table II is
0.007 milligrams uranium per cubic meter of air. The specific activity for
natural uranium is 6.77 X 10'7 curies per gram uranium. The specific activity
for other mixtures of U-238, U-235 and U-234, if not known, shall be:
SA - 3.6X10-7 curies/gram U2 (U-depleted) „
SA = (0 4 + 0 38E + Oo0034E) X 10"°, E lesser than or equal to 0.72,
where E*is the percentage by weight of U-235, expressed as percent.
NOTE:
In any case where there is a mixture in air or water of more than one
radionuclide, the limiting values for purposes of this Appendix
should be determined as follows:
1) If the identity and concentration of each radionuclide in the mixture
are known, the limiting values should be derived as follows: Deter-
mine, for each radionuclide in the mixture, the ratio between the _
quantity present in the mixture and the limit otherwise established
in Appendix "A" for the specific radionuclide when not in a mix-
ture. The sum of such ratios for all the radionuclides in the
mixture may not exceed "1" (i.e., "unity").
EXAMPLE: If radionuclides (a), (b), and (c) are present in
concentrations Ca, Cb, and C , and if the appliable maximum
permissible concentrations (MPC's are MPC , MPCu, and MPC
respectively, then the concentrations shall be limited so that
the following relationship exists:
r r C,. lesser than
Ca b 1_ or
MPC,. equal to 1
MPC,
340-54
January, 1987
A 3-12
-------
APPENDIX 4
INCINERATOR CONTROL FUNCTIONS
A 4.1
FEED SYSTEM
Waste feed system controls are designed to maximize the feed within regulatory constraints
(e.g., a maximum allowable feedrate) and operating constraints (e.g., high primary chamber
temperature, which limits feedrate when the incinerator is burning high heat value waste
materials and high gas velocity, which restricts feedrates for high moisture content and/or high
heating value waste).
In a typical feed control system, the operator inputs a setpoint to the controller. The setpoint
can be a feed rate (e.g., for a continuous feed system such as a screw feeder or liquid waste
system) or a charge weight (e.g., for a batch system such as a ram system). In a continuous
solid feed, the system would use a weigh belt or weigh hopper to sense the feedrate of solids,
compare the feedrate to the setpoint and adjust the speed of the screw feeder. In a batch system,
the charge setpoint is the primary method of controlling the feedrate. Liquid waste feedrate is
controlled by comparing the flowrate measurement with the setpoint and adjusting the position
of a control valve.
A 4,2
COMBUSTION CONTROLS
Combustion controls maintain a safe temperature in the primary and secondary combustion
chambers. This requires the interaction of control loops for temperature, supplemental fuel
flowrate, coolant flowrate, and combustion air flowrate. In an incinerator, interaction between
combustion and waste feed control loops is also possible. The combustion control systems vary
with incinerator type as follows.
A 4-1
-------
A 4.2.1
Rotary Kiln
Rotary Mln temperature is controlled by feeding the measured temperature to a controller that
compares it with the setpoint. Several scenarios are possible:
Scenario 1: The measured temperature is below the setpoint and coolant flow is
off. The control signal orders increased use of auxiliary fuel. In the lead/lag
control system, the signal increases the combustion air flow by increasing the
opening of the combustion air damper downstream of the forced draft (FD) fan.
After the air damper opens further, the fuel control valve opens proportionately.
Scenario 2: The measured temperature is above the setpoint and coolant flow is
off. The control signal causes the fuel flow to decrease by closing the fuel valve
further. When the fuel valve starts to close, the air damper closes
proportionately.
In Scenarios 1 and 2 above, the cross limiting lead/lag system ensures adequate combustion air
to maintain a stable auxiliary burner flame. Fuel and air flowrates are kept in proportion to each
other under any change in flowrate. This is the cross-limiting feature. On an increased demand
for fuel, air flow is increased followed by increased fuel flow, and on a decreased demand for
fuel, fuel flow is decreased followed by decreased air flow. This is the lead/lag feature.
In Scenarios 3 and 4 below, coolant flows are used to control the primary chamber temperatures.
In these cases, the auxiliary burner is at minimum firing. Either water or air can be used as
coolants, but water is more effective due to its higher heat capacity and the energy associated
with the latent heat of vaporization.
Scenario 3: The measured temperature is above the setpoint. The control signal
causes increased water flow by opening the water control valve further.
A 4-2
-------
Scenario 4: The measured temperature is below the setpoint, the control signal
decreases the water flow by closing the water control valve further.
Accurate temperature measurement in a rotary kiln can be difficult. The thermocouple should
be protected by a thermowell and the location should be carefully chosen to avoid inaccurate
readings. With a dry ash removal system, excessive air leakage can cause low readings. The
steam generated by a wet ash removal system can cause low readings.
The primary chamber of a rotary kiln can operate under either reducing or oxidizing conditions.
For an incinerator operating under oxidizing conditions, the use of oxygen trim control is
recommended to control excess oxygen. A solid state zirconium oxide oxygen analyzer is
preferred for this application because it can be used in situ or with a very short sampling line.
The use of an oxygen meter improves incinerator response to transients and reduces the
occurrence of carbon monoxide spikes.
The use of feedforward control when firing a liquid waste also improves the response of the
incinerator to transients. This is accomplished by measuring the feedrate of the liquid waste and
using an estimated heating value. The controller uses the feedrate measurement and the
estimated heating value to calculate an air requirement. The air requirement, converted to a
signal, acts on the air damper to the forced draft fan.
Unless the unit is of airtight construction, draft or negative pressure must be maintained
throughout any hazardous waste incineration system to prevent fugitive emissions. This is
achieved by measuring the draft at the point of highest pressure, comparing the draft to the
setpoint, and either adjusting the damper or adjusting the speed of the induced draft (ID) fan.
The location of highest pressure depends upon the type of incinerator. For a rotary kiln, the
highest pressure occurs in the primary chamber. For a controlled air incinerator, the highest
pressure may occur in either the primary chamber or secondary chamber. For a fluidized bed
incinerator, the highest pressure occurs above the air distributor, but the draft is controlled by
A 4-3
-------
the pressure in the freeboard. It is good practice to control draft with the ID fan or its dampers
and to control excess air with the forced draft (FD) fan or its dampers.
The combustion controls for the secondary combustion chamber of a rotary kiln incinerator
should be controlled in a manner similar to the primary chamber. The control, however, is less
complex. Temperature should be controlled by a cross-limited lead/lag control system.
A 4.2.2
Controlled Air Incinerator
Temperatures of the primary combustion chamber and the secondary combustion chambers are
the main control variables in the controlled air incinerator. The temperature in the primary
chamber is controlled by varying air flow. If the measured temperature is higher than the
setpoint, air flow is decreased by closing the damper that controls air flow to the primary
chamber. This reduces the rate of combustion. If the measured temperature is lower than the
setpoint, the air flow is increased by opening the damper.
The temperature in the secondary chamber is controlled by varying air flow to the chamber in
a manner opposite to the primary chamber. If the measured temperature is higher than the
setpoint, air flow is increased by opening the damper that controls air flow to the secondary
chamber. If the measured temperature is lower than the setpoint, the air flow is decreased by
closing the damper.
A 4.2.3
Fluidized Bed Incinerator
Temperature, excess air, and limestone injection rates are important control variables for
fluidized bed incinerators. The temperature of the fluidized bed incinerator responds slowly to
transient conditions due to the high heat holding capacity of the bed. Control of the temperature
can be accomplished by adding supplemental fuel, injecting water, and controlling excess air.
A minimum air flow must be maintained to ensure fiuidization. Control of excess air can be
A 4-4
-------
accomplished by oxygen trim control using an oxygen analyzer. Acid gas removal is
accomplished by controlling the feedrate of limestone injection.
A 4.3
AIR POLLUTION CONTROL SYSTEM
The quench system can bring the flue gas temperature to the adiabatic saturation temperature of
water, which is relatively constant, or to a controlled saturation temperature. The type of
system is dependent upon the type of air pollution control equipment used downstream of the
quench system.
Systems that reach the adiabatic saturation temperature do not require temperature control. Total
dissolved solids (TDS), pH of the quench water, and the level of drained water in the collection
sump may have to be regulated. TDS is controlled by measuring the electrical conductivity of
the water in the collection sump, comparing the value to a setpoint, and controlling the rate of
blowdown to maintain the setpoint. The pH of the quench water is maintained by measuring the
pH in the collection sump with a glass electrode, comparing the pH to the setpoint, and adjusting
a control valve or the speed of a metering pump to inject the proper quantity of neutralizing
agent. Level control an be obtained by measuring the level in the collection sump and by
adjusting the position of the control valve for make-up water.
Systems that do not reach the adiabatic saturation temperature require a temperature control
loop. The temperature downstream of the quench is measured and compared to the setpoint.
If the value is above the setpoint, coolant flow is increased by opening the control valve further.
A 4.4
ACID GAS REMOVAL
For rotary kilns and controlled air incinerators, acid gas removal is the main function of the
packed scrubber or the spray dryer. A venturi scrubber also removes acid gases but usually
requires a packed scrubber downstream to complete the acid gas removal.
A 4-5
-------
A 4.4.1
Packed Bed Scrubber
Scrubber liquid to gas ratio, PH, and temperature are important control variables for packed
scrubbers. The liquid to gas ratio can be optimized by calculating the ratio of the flue gas and
liquid flowrates, by comparing the ratio to the setpoint and by adjusting the liquid flowrate
control valve. Alternatively, the liquid flow can be maintained at an adequate flowrate that
provides a sufficient liquid to gas ratio throughout the operating range of the incinerator. The
PH of the scrubber liquid should be controlled by measuring the PH of the liquid exiting the
scrubber, comparing the value to the setpoint and adjusting the rate of caustic addition through
a control valve. Usually, temperature is controlled to adequately protect the particulate removal
device.
A 4.4.1
Sorav Dryer
Temperature, slurry concentration, and liquid/gas ratio are important control variables for spray
dryers. The inlet temperature of a spray dryer ranges from 400'F.to 600°F and the outlet
temperature ranges from 250°F to 300°F. Control of temperature and liquid/gas ratio is
discussed above.
A 4.5
PARTICULATE REMOVAL
The main particulate removal devices are venturi scrubbers, fabric filters (baghouses), and wet
electrostatic precipitators (WESPs). High temperature ceramic filters, sintered metal filters, and
electrostatic precipitators have also been used for particulate removal.
A 4.5.1
Venturi Scrubber
Temperature, liquid/gas ratio, scrubber water PH, and scrubber pressure drop are important
control variables for a venturi scrubber. Control of temperature, liquid/gas ratio and scrubber
water pH have been discussed above. The scrubber pressure drop can be controlled by
A 4-6
-------
measuring the differential pressure across the venturi and adjusting the throat opening to meet
the setpoint requirements.
A 4.5.2
Fabric Filter (Baghouse')
Temperature and pressure drop are the control variables for the fabric filter. Temperature
control has been discussed above. The pressure drop across the bags is controlled by periodic
cleaning.
Compressed air is directed inside each bag at set intervals to discharge the dust that has
accumulated on the external surface of the bag. Timed flow reversals are used on independent
sections of the baghouse. A shaker mechanism physically shakes bags in a section of the
baghouse. The shaker operates in sequence with fresh air dampers that provide a reversing flow
to aid dust removal.
A 4.5.3
Temperature, water flow, and direct current (DC) voltage are the critical control variables for
a wet electrostatic precipitator. Control of temperature has been discussed above. Water flow
is usually maintained at a constant rate high enough to ensure cleaning. Voltage is maintained
by an automatic controller that maintains a sparking rate. When the peak voltage drops the
WESP must be water washed to regenerate maximum paniculate removal efficiencies.
A 4.6
FINAL PARTICULATE AND RADIOACTIVE GAS REMOVAL
The primary paniculate removal devices are followed by a condensation step and a reheat step
to provide a superheated flue gas for final paniculate and radioactive gas removal (if necessary).
The condensation and reheat steps are usually accomplished by heat exchangers. The
superheated gas is then passed through a high efficiency paniculate air (HEPA) filter for removal
of ultrafine particles and a carbon adsorption bed for removal of radioactive gases.
A 4-7
-------
Temperature and pressure drop are important variables for the HEPA filters and the carbon
adsorption beds. These are usually monitored.
A 4-8
-------
APPENDIX 5
INCINERATOR MONITORING SUBSYSTEMS
A5.1
FEED SYSTEM
Feed system monitors check the operation-of the feed preparation equipment, check the
atomization parameters for the liquid waste, and measure the feedrates of solid and liquid
wastes. The feed preparation equipment must be operating to ensure adequate size distribution
of the solid wastes sent to the incinerator. Because high liquid waste pressures may cause
overfeeding of the incinerator, and low atomizing media pressures could produce emission
problems due to inadequate atomization, waste and atomizing media pressure must be monitored.
If the liquid waste requires heating, the liquid waste temperature should also be monitored to
ensure adequate atomization. For fiuidized bed incinerators, limestone or other acid gas removal
agents must be monitored to ensure adequate acid gas removal.
A 5.2
PRIMARY COMBUSTION CHAMBER
The primary combustion chamber temperatures and pressures must be monitored. Temperature
monitoring ensures adequate waste destruction, and protects equipment. High temperature
produces agglomeration in fiuidized beds and slagging and refractory damage in rotary kilns and
controlled air incinerators. Pressure must be monitored to prevent loss of vacuum that can cause
fugitive emissions from openings in the primary chamber. Since fiuidized bed incinerators have
no secondary combustion chamber, low oxygen and high carbon monoxide concentrations must
be monitored at the chamber exit to ensure adequate waste destruction.
A 5.3
BURNER SYSTEM
The burner systems associated with both the primary and secondary chamber are monitored
separately but the monitored variables are identical. The primary purpose of the burner
A 5-1
-------
monitoring system is to prevent explosions. Burner monitoring consists of checking fuel,
combustion air, and atomizing media pressures; completion of purge; and loss of flame. Low
fuel pressure must be monitored to prevent unstable flames. High fuel pressure is monitored
to prevent extinction of flames due to blowoff and to prevent overfiring. Low combustion air
pressure and low atomizing air pressures are also monitored to prevent unstable flames. An air
purge is required to remove potential accumulations of fuel which could explode if exposed to
an ignition source. The flame is monitored to prevent an accumulation of an explosive mixture
after a flameout.
A burner trip for loss of flame and/or lack of air purge is recommended for startup of the
incinerator. However, for most of the incinerator operating time these trip functions are not
required or even recommended, as discussed below. Loss of flame should only generate an
alarm when the incinerator is operation above 1400°F. The 1400°F level is a temperature at
which it is generally agreed that accidental fuel input would be ignited by the hot incinerator
interior before a hazardous accumulation could occur. This rule does not apply to boilers which
contain cold waterwalls. A purge prior to burner light-off is unnecessary if combustion is
already occurring in the combustion chamber.
A 5.4
SECONDARY COMBUSTION CHAMBER
The secondary combustion chambers used in rotary kilns and controlled air incinerators must be
monitored for temperature, oxygen, carbon monoxide, and residence time. High temperature
must be monitored to prevent damage to the equipment. Low temperature, low oxygen
concentration, high carbon monoxide concentration, and residence time (gas velocity) are
monitored to ensure adequate waste destruction.
A 5.5
AIR POLLUTION CONTROL SYSTEM
The air pollution control system consists of a quench unit plus devices to control emissions of
gases and particulates. With the exception of the burner trip required for high temperature or
A 5-2
-------
loss of coolant flow in the quench, an out-of-limit variable produces a feed cutoff to protect
against emissions.
The quench reduces the temperature of the hot gases that exit from the combustion equipment
to levels suitable for the downstream air pollution control equipment. Temperature and coolant
fiowrates are the main variables monitored. High temperature is monitored to protect the
downstream equipment. If a baghouse or dry electrostatic precipitator is used, low temperature
is monitored to control particulate emissions because liquid interferes with the proper operation
of these devices. Coolant fiowrates are monitored to ensure adequate cooling.
The variables monitored for a venturi scrubber are pressure drop, vacuum, liquid-to-gas ratio
or liquid flowrate, and scrubber water pH. Pressure drop, pH, and liquid-to-gas ratio or liquid
flowrate, are monitored to prevent excessive particulate emissions. High vacuum is monitored
to protect the equipment.
Fabric filters or baghouses are monitored for broken bags and high pressure drops. These
variables are monitored to prevent excessive particulate emissions and to protect the baghouse.
Wet electrostatic precipitators are monitored for low DC voltage and water fiowrates. Low DC
voltage indicates inadequate field strength for adequate particulate removal. Inadequate water
fiowrates cause ineffective washing of plate surfaces.
Packed scrubbers are monitored for low scrubber water flowrate, pH of the scrubber water, and
high pressure drop. Adequate pH and scrubber water flowrate are required to achieve
satisfactory acid gas removal. High pressure drop indicates that cleaning is necessary.
HEPA filters and carbon beds are monitored for high pressure drops to determine when
changeout of the HEPA filter element or the carbon bed module is required.
A 5-3
-------
A 5.6
GENERAL MONITORING
The subsystems which affect the entire incinerator are the ID fan, instrument air supply, and
electrical power supply. Loss of vacuum, excessive vibration of the ID fan, low instrument air
pressure, or loss of electrical power result in a burner trip.
A 5.7
AIR POLLUTION MONITORS
In addition to the equipment monitors, air pollution monitors record carbon dioxide (used for
efficiency calculations on PCB incinerators), total hydrocarbons, nitrogen oxides, and sulfur
dioxide.
A 5-4
-------
APPENDIX 6
COST ELEMENTS
A 6.1 CAPITAL COSTS
Capital costs are classified as direct or indirect. Direct costs include site preparation,
equipment, materials, and labor necessary for physical construction of the plant. Indirect costs
include engineering, permitting, regulatory costs, and financing costs.
A 6.1.1 Site Preparation Costs
These costs include planning, management, site design and development, equipment, utility
preparation, emergency and safety equipment. Also included are soil excavation, feedstock
preparation, and feed handling costs which will vary with the site.
A 6.1.2 Permitting and Regulatory Costs
These costs are associated with regulatory compliance and may include national or regional
permits. Preparation of permit applications, sampling and analysis plans, quality assurance
project plan, and trial burn reports are usually required. A trial burn may be required to prove
overall system performance. The costs of performing the trial burn as well as sampling and
analysis activities should be included.
In addition, the costs for developing operating procedures and training operators, as well as
health and safety operating manual should be considered.
A 6-1
-------
A 6.1.3 Equipment Costs
These costs include the design, engineering, materials, and equipment procurement, fabrication,
and installation of the incinerator. These direct costs include all subsystems and components,
for example, the emission control equipment.
A 6.1.4 Start-up and Fixed Costs
After the incinerator is constructed and training is completed, the unit must be started and
operated to check the mechanical and technical integrity of the equipment and controls.
A 6.2 OPERATING COSTS
Operating costs include operation, maintenance, transportation, and disposal. Operations and
maintenance include the direct cost of material, labor, replacement parts, consumable goods
(filters, drums, clothing), utilities, and tools.
A 6.2.1 Labor Costs
This category includes personnel such as operators and supervisors, usually ranging from 2 to
8 percent of the total annual cost. Labor costs can be reduced by increased system automation;
they are also affected by the size of the plant, its location, and operating time.
A 6.2.2 Supplies and Consumable Goods
These include filters, drums, clothing, health and safety supplies, and chemicals (such as caustic
soda solution for acid gas scrubbing). Fuel (oil, gas) costs depend on the heat value of the waste
feed.
A 6-2
-------
A 6.2.3 Utility Costs
These costs vary with the incinerator utilization. Fuel is required for the secondary combustion
chamber heating requirements. Power costs include electrical requirements for pumps, fans,
mixers, belt drives, lighting, etc. Water may be used for cooling, and in scrubber solution
makeup.
A 6.2.4 Disposal
Transportation and disposal costs depend on the type of material, the distance transported, and
the type and availability of a disposal site. In the case of radioactive waste, these costs can be
significant. Exhibit 2 is the Barnwell, South Carolina, rate schedule for disposal of low-level
radioactive waste, effective April 1, 1989.
A 6.2.5 Analytical Costs
In order to ensure that a unit it operating efficiently and meeting environmental standards, a
program for continuously analyzing waste feed, stack gas, ash, and water quality is required.
A 6.2.6 Modification. Repair, and Replacement Costs
These costs vary with system design, waste feed composition, and site characteristics. Five
percent of the installed cost is sometimes used for this category.
A 6.2.7 Indirect Operating Costs
These include taxes, insurance, administration expenses, overhead, and capital charges. For
taxes, insurance, and administration, 4 percent of the capital cost is used for some estimates.
A 6-3
-------
-------
Appendix 7
General Operations Problems and Preventive Maintenance Actions
TABLE A 7-1 Typical Feed Problems
Source of Problems
Consequence of Problem
Preventive Maintenance
Action
PVC-HC1
Rubber - SO2
Teflon - F
Batchwise feeding system
Air pollution control (APC) Proper materials selection;
system corrosion. control system design.
Can exceed chemical release APC system design
limits. modification.
Can exceed chemical release APC system design.
limits.
Transient off-gas Afterburner will reduce
composition and temperature off-gas problems; feed small
with occurrence of batches.
incomplete combustion.
A 7-1
-------
TABLE A 7-2 Typical Combustion Operating Problems
Source of Problems
Consequence of Problem
Preventive Maintenance
Action
NOX - formation at
t> 2200°F
Volatilization (metal oxides)
Incomplete combustion
Puffing
Release limit exceeded
Deposition on heat
exchanger and filters.
Accumulation of
radionuclides. Clogging.
Filter clogging. Release
limits exceeded.
Overpressure inside furnace,
possibility of outside
contamination.
Control temperature.
Scrubbing or ammonia
injection.
Subcool vapors.
Improve incineration.
Design problem. Provide
pressure relief valve to stack
or relieve overloading.
A 7-2
-------
TABLE A -7-3 General Maintenance and Troubleshooting Air Pollution Control Equipment
Equipment
Indicators
Problems
Recommended
Maintenance and
Troubleshooting
Quencher Erratic outlet temp.
Partially plugged nozzles
High variation incinerator feed
moisture
Low gas flow rate (< 30 ft/sec)
Water droplets impinging on
thermocouple
Inspect and replace plugged nozzles
Control moisture feed to incinerator
Increase gas flow rate to design
range
Relocate thermocouple, replace
defective nozzles
Consistently high outlet
temperature
• Plugged nozzles
• Lower water flow rate and high
temperature
• Excessive gas velocity (> 50 ft/sec)
Inspect and replace plugged nozzles
Calibrate water flowmeter to adjust
for evaporation loss
Reduce gas flow rate
Venturi
scrubber
Erratic pressure
differential
Plugged nozzles
Erosion
Corrosion
Adjustable throat diameter is too
wide
Inspect headers, flanges, and
nozzles
Reduce throat diameter and adjust
liquid flow rate
Inspect throat regularly for deposits
and wear
Absorption
scrubber
Surging pressure
differential (>10%)
Face velocity in excess of 12 ft/sec
Plugged tray sections
Nonuniform scrubber liquor
distribution
Leaking seals
Localized plugging of packing
Hole in the packing
Flooding
Inspect spray nozzles, water flow
rate weir boxes, and downcomers
for proper operation and seals.
Inspect packing; adjust caustic
concentration to 15-20 percent
• Decrease liquid flow rate
• Check for plugging of packing
Fabric filter
(baghouse)
Excessive pressure
differential
Excessive gas flow rate
Bag blinding (high dust loadings)
Leaking air lock or dampers
Faulty cleaning mechanism
Excessive dust accumulation in
clean side of bags
Reduce gas flowrate; check
bleed air
Inspect cleaning mechanism;
replace bags
Check proper temperature of gas to
prevent condensation
Inspect for proper removal of
collected ash from hoppers
A 7-3
-------
TABLE A 7-4 Recommended Inspection and Maintenance Frequency
Operation
Equipment/parameters Calibration
Incinerator equipment
Waste feed/fuel (2)
systems
O and CO Monitors Weekly
Gas How monitors:
• Direct gas velocity Weekly
• Indirect fan amps 6 months
Other incinerator
monitoring equipment
(flame scanners, air
blowers, etc.) —
APC
APC support systems —
APC performance
instrumentation Weekly
I&M Frequency
and Monitoring eauioment
Inspection
Daily
Daily
Continuous
Continuous
Continuous
Daily
Weekly
Daily
Daily
Service
(1)
(1)
(1)
(1)
(1)
(1)
(1)
(1)
Emergency systems
Alarms waste cutoffs
Weekly
Weekly
Weekly
Weekly
Weekly
—
Weekly
Weekly
Weekly
Weekly
Weekly
Weekly
Weekly
• —
Weekly
Weekly
(1) Equipment manufacturer recommendation.
(2) Equipment manufacturer recommendation or no less than monthly.
Source: Acurex 1986
Frankel 1987c
A 7-4
-------
TABLE A 7-5 Operating Parameters for HEPA Filters
Range
Comment
Temperature
Flow rate
Pressure drop
Humidity
Particulate loading
Efficiency
Corrosive gases
250°F maximum
500°F maximum
1000°F maximum
4200-160,000 fWhr
1.0" H2O
2.0" H20
0-95%
up to 4.5 Ib
99.97%
Up to several percent of NOX, HNO3,
and HF in gas stream
particle board frame and rubber
base adhesive
steel frame and silicon adhesive
steel frame and glass packing seal
clean pressure drop at rated flow
particulate loaded pressure drop
condensation should be avoided
depends on particle size, humidity,
and surface area of filter
as tested with 0.3 urn DOP aerosol
acid-resistant fibers (Nomex or
Kerler), separators, and sealants are
used
A 7-5
-------
TABLE A 7-6 Off-Gas Cleaning System Operating Problems
Source of Problem
Consequence of Problem
Preventive Maintenance Action
Humidity
Temperature below the dewpoint of
inorganic acids
High release of acid
Clogging of filter (HEPA).
Corrosion.
Clogging (condensation of acids and
tars).
H-3 (Tritium).
C-14.
Cs, Ru, Zn.
HCi, NOX, SOX) and HF
High content of HC and solid burnable Risk of fire in filter system.
particles in the offgas
Low decontamination factor (DF)
Mixing chamber
Quencher
Heat exchangers
Build-up on precoated high temperature
filters
Bag filter
Personnel exposure
Increasing of off-gas mass.
Higher water content in the off-gas
which gives higher corrosion risk.
Plugging of the tubes giving high
pressure drop and/or reduced heat
transfer coefficient.
Corrosion.
Filter life.
Secondary waste.
Risk of fire and holes.
Secondary waste or formation of HF if
incinerated.
Reheat or add heater.
Reheat if scrubber is used or keep
temperature between 175-190°F.
Remove acid gases.
Special development needed.
Same as above.
Problem not likely.
Cooling before filtration to <480°F;
HEPA filter recommended.
Scrubbing needed.
Cannot be treated as gas; must be
treated in the process itself.
Improvement of the incineration process
is needed or installation of spark
catcher.
For better DF, improve the incinerator
process.
Install easy handling systems for
maintenance and operation.
Increasing size of equipment is
necessary.
Special feeding system is needed to
control cooling rate.
Periodic cleaning is necessary.
Material and design problem.
More efficient secondary combustion.
High efficiency of filtration for particles
>3 microns.
A 7-6
-------
EXHIBIT 1
Combustible Mixed Waste volumes in storage as of April
Facility
Los Alamos National Laboratory
Lovelace Inhalation Toxicology
Mound_ Plant
Pantex
Argonne National Laboratory - East
Argonne National Laboratory - West
Brookhaven National Laboratory
Grand Junction Project Office
Idaho National Engineering Laboratory
Colonie Interim Storage Site
Fernald
Oak Ridge National Laboratory
Paducah Gaseous Diffusion Plant
Portsmouth Gaseous Diffusion Plant
Weldon Spring Remedial Action Project
Bettis Atomic Power Laboratory
Naval Reactors Facility
Hanford Site
Rocky Flats Plant
Santa Susana Field Laboratory
Lawrence Berkeley Laboratory
Savannah River Site
(a> Obtained from DOE/EM-32. 2/19/91
Combustible Cm3) &W
LLW TRU
12.5
1.1
16.3
3.6
12.5 37.5
0.6
3.3
0.1
7281.7 9622.0
2.1
5.0
12.4
10.6 1.7
9.8
37.5
0.3
0.2
106.4 95.6
112.1 97.3
2.6
3.2
Combustible Non-
combustible Mix Cm3') (°)(d)
LLW TRU
4.0
0.1 0.2
3.8 0.1
2844.7 1549.0
0.6
19.0
680.0
0.4
22.0 22.5
1.9
3967.1 3043.0
(b)
(c)
(d)
Low level waste (LLW) and transuranic waste (TRU) radioactive mixed waste matrices containing
greater than 90% combustible material
Low level waste (LLW) and transuranic waste (TRU) radioactive mixed waste matrices containing at
least 10% volume of both combustible and noncombustible materials
Does not include waste quantities subject to solvent Land Disposal Restriction rules
El-1
-------
-------
EXHIBIT 2
BARNWELL LOW-LEVEL RADIOACTIVE
WASTE MANAGEMENT FACILITY
RATE SCHEDULE
All radwaste material shall be packaged in accordance with Department of Transportation and Nuclear
Regulatory Commission Regulations in Title 49 and Title 10 of the Code of Federal Regulations, Chem-
Nuclear's Nuclear Regulatory Commission and South Carolina Radioactive Material Licenses, Chem-Nuclear's
Bamwell Site Disposal Criteria, and amendments thereto.
1. BASE DISPOSAL CHARGES:
(Not including Surcharges, Barnwell County
Business License Tax, and Cask Handling Fee)
A. Standard Waste
B. Biological Waste
C. Special Nuclear Material (SNM)
$36.87/ft3
$38.52/ft3
$36.87/ft3
plus $4.75 per Gram SNM
None: Minimum charge per shipment, excluding Surcharges and specific other charges is $800.00.
2. SURCHARGES:
A. Weight Surcharges (Crane Loads Only)
Weight of Container Surcharge Per Container
, 0 - 1,000 Ibs.
1,001 - 5,000 Ibs.
5,001 - 10,000 Ibs.
10,001 - 20,000 Ibs.
20,001 - 30,000 Ibs.
30,001 - 40,OOO Ibs.
40,001 - 50,000 Ibs.
greater than 50,000 Ibs.
No Surcharge
$ 430.00
$ 760.00
$1,070.00
$1,390.00
$2,030.00
$2,670.00
By Special Request
B. Curie Surcharges for Shielded Shipment:
Curie Content Per Shipment Surcharge Per Shipment
$ 2,650.00
$ 2,990.00
$ 3,980.00
$ 5,990.00
$ 7,320.00
$ 9,910.00
$11,870.00
$15,900.00
$19,900.00
$23,900.00
$31,800.00
By Special Request
0 -
5 -
15 -
25 -
50 -
75 -
100 -
150 -
250 -
500 -
1,000 -
5,000
5
15
25
50
75
100
150
250
500
1,000
5,000
Effective April 1, 1989
(4537g)
E2-1
-------
EXHIBIT 2 (Continued)
Bamwell Rate Schedule
Page Two
C. Curie Surcharges for Non-Shielded Shipments Containing Tritium and Carbon 14:
Curie Content Per Shipment Surcharge Per Shipment
0-100
Greater than 100
No Surcharge
By Special Request
D. Class B/C Waste Polyethylene High Integrity Container Surcharge
TvpeofHIC
(1) Large liners with maximum
dimension of 82" diameter
and 79" height
(2) Overpacks with maximum
dimension of 33" diameter
and 79" height
(3) 55-gallon drum size with
maximum dimension of 25.5"
diameter and 36" height
(4) Poly HICs which do not conform
to one of the above three
categories require prior approval.
Surcharge Per HIC
$4,700.00
$1,570.00
$400.00
Upon Request
E. Special Handling Surcharge may apply on unusually large or bulky containers. These
types of containers are acceptable upon approval of prior request.
3. OTHER CHARGES
A. Cask Handling Fee
B. Taxes and Special Funds
1. Extended Care Fund
2. South Carolina Low-Level Radioactive
Waste Disposal Tax
3. Southeast Regional Compact Fee
$1,050.00 per cask, minium
$2.80 per ft3
$6.00 per ft3
$.66 per ft3
4. A 2.4% surcharge is added to each bill to cover Barnwell County Business License
Taxes.
NOTE: ITEMS 3.B. 1, 2, AND 3 ARE INCLUDED IN ITEM 1, BASE DISPOSAL CHARGES.
Effective April 1, 1989
(4537g)
E2-2
-------
EXHIBIT 3
Half Lives of Selected Radionuclides
Nuclide
H-3
C-14
P-32
S-35
Cr-51
Mn-54
Fe-55
Fe-59
Co-60
Ni-63
Zn-65
Se-75
Sr-90
Zr-95
Nb-95
Tc-99
Mo-99
1-125
1-129
1-131
Cs-134
Cs-137
Ce-144
Pb-210
Po-210
U-234
U-235
U-238
Np-237
Pu-238
Pu-239
Pu-240
Pu-241
Am-241
Half Life
12.3y
5730 y
14.28 d
87.39 d
27.70 d
312.20 d
2.68y
44.56 d
5.27 y
100. ly
244.0 d
118.45 d
28.82 y
63.98d
34.97 d
2.12 x lO'y
66.02 h
60.25 d
1.17x 107y
8.04 d
2.06 y
30.17y
284.5 d
22.26 y
138.37 d
2.446 x 10s y
7.038 x 10s y
4.468 x 10* y
2.14x lO^y
86.4 y
2.41 x 10" y
6,580 y
14.3 y
432 y
Radiation Emitted
beta
beta
beta
beta
electron capture
electron capture
electron capture
beta
beta
beta
electron capture
electron capture
beta
beta
beta
beta
beta
electron capture
beta, gamma
beta
beta
beta
beta
beta
alpha
alpha
alpha
alpha
alpha, beta
gamma
alpha, gamma
alpha, gamma
alpha, gamma
alpha, beta
alpha, gamma
Principle Means of
Production
Fission; Li-6 (n,d)
N-14 (n,p)
P-31 (n, gamma)
S-34 (n, gamma)
Cr-50 (n, gamma)
Fe-56 (d, alpha)
Fe-54 (n, gamma)
Fe-58 (n, gamma)
Co-59 (n, gamma)
Ni-62 (n, gamma)
Zn-64 (n, gamma)
Se-74 (n, gamma)
Fission
Zr-94 (n, gamma)
Daughter Zr-95
Fission, Mo-98
(n, gamma)
Mo-98 (n, gamma)
Sb-123 (alpha, 2n);
daughter Xe-125
Fission
Fission
Cs-133 (n, gamma)
Fission
Fission
Descendant Ra-226
Daughter Bi-210
Daughter Pu-238
Natural source
Natural source
U-238(n,2n)
U-237 (beta)
Np-237 (n, gamma)
Np-238 (beta),
daughter Cm-242
U-238 (n, gamma)
U-239 (beta),
Np-239 (beta)
Multiple n-capture
Multiple n-capture
Daughter Pu-241
*U.S. GOVERNMENT PRINTING OFFICE: 1991—517-003/47010
E3-1
-------
-------
TECHNICAL REPORT DATA
(Please read Instructions on the reverse before completing)
EPA 520/1-91-010-1
3. RECIPIENT'S ACCESSION NO.
4. TITLE AND SUBTITLE
Radioactive and Mixed Waste Incineration Background
Information Document: Volume I - Technoloov
5. REPORT DATE
1991
PERFORMING ORGANIZATION CODE
'. AUTHOR(S)
Office of Radiation Programs and Center for Technology
Control
8. PERFORMING ORGANIZATION REPORT NO
9. PERFORMING ORGANIZATION NAME AND ADDRESS
Environmental Protection Agency
Office of Radiation Programs (ANR-461)
401 M St., S.W.
Washington, D.C. 20460
10. PROGRAM ELEMENT NO.
11, CONTRACT/GRANT NO.
12. SPONSORING AGENCY NAME AND ADDRESS USEPA ~
Office of Air and Radiation and Office of Research
and Development
Washington, D.C. 20460
13. TYPE OF REPORT AND PERIOD COVERED
Final
14. SPONSORING AGENCY CODE
15. SUPPLEMENTARY NOTES
This background document, consisting of Volume I - Technology and Volume II - Risks of
Radiation Exposure, provides a broad look at technology issues surrounding the inciner-
ation of radioactive and mixed wastes. It is intended to highlight major consideration
and to provide direction that would enable the reader who must deal in depth with
incineration to focus on and seek specific information on concerns appropriate to a
particular situation. It is not a comprehensive text on incinerator design, use or
regulation. The information presented in Volume I was gathered by telephone -contacts
with operators of existing incinerators, site visits, agency contacts, and literature
searches. The contents present a. distillation of material deemed to be most relevant;
it includes only a small fraction of the total amount of information collected.
Wherever possible, actual operating data have been used to illus-trate principles, how-
ever, inconsistencies in operational data acquisition have resulted in very limited
availability of data that can be used for general assessment or purposes of comparison.
Even though the existing data base on operation and resulting emissions and ash resi-
dues from radioactive waste incinerators is still quite small, it has been demonstrated
that incineration can achieve significant volume reductions for radioactive waste.
7.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b.lDENTIFIERS/OPEN ENDED TERMS
c. COSATI Field/Group
Radwaste Treatment
Radwate Incineration
.Mixed Waste Incineration
Radwaste or .Mixed Waste Reduction
Thermal Destruction
Volume Reduction
8. DISTRIBUTION STATEMENT
Release Unlimited
19. SECURITY CLASS (Tills Report)
Unclassified
21. NO. OF PAGES
20. SECURITY CLASS (This page I
22. PRICE
EPA Form 2220—1 (Rev. 4—77) PREVIOUS EDITION is OBSOLETE
-------
-------
-------
------- |