EPA906-D-98-001
Interim Final
USER'S GUIDE FOR THE U.S. EPA REGION 6
DELISTING RISK ASSESSMENT SOFTWARE
(DRAS)
Office of Solid Waste
Prepared by
Multimedia Planning and Permitting Division
U.S. Environmental Protection Agency
Region 6
Dallas, TX 75202
August 31, 2000
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USER'S GUIDE FOR THE U.S. EPA REGION 6
DELISTING RISK ASSESSMENT SOFTWARE
(DRAS)
Submitted to:
U.S. EPA Region 6
Dallas, TX 75202
Prepared By:
Tetra Tech EM, Inc.
One Dallas Centre
350 North St. Paul Street, Suite 2600
Dallas, TX 75201
and
HydroGeoLogic, Inc.
1155 Herndon Parkway, Suite 900
Herndon,VA 20170
and
HydroGeoLogic, Inc.
13740 Research Boulevard, Suite N-5
Austin, TX 78750
Version 1.1
August 31,2000
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TABLE OF CONTENTS
Page
1.0 INTRODUCTION 1
1.1 OBJECTIVES 1
1.2 BRIEF OVERVIEW OF THE SOFTWARE 1
1.3 USING THE DRAS SOFTWARE IN SEVEN EASY STEPS 2
2.0 SYSTEM REQUIREMENTS 4
2.1 MINIMUM SYSTEM REQUIREMENTS 4
2.2 RECOMMENDED SYSTEM REQUIREMENTS 4
3.0 INSTALLATION 5
4.0 BRIEF OVERVIEW OF RUNNING THE SOFTWARE 6
4.1 DELISTING LEVEL ANALYSIS VERSUS RISK AND
HAZARD ANALYSIS 6
4.2 DELISTING LEVEL ANALYSIS 6
4.3 RISK AND HAZARD ANALYSIS 6
4.4 REQUIRED INPUT 6
4.5 OUTPUT 7
4.6 APPLICATION OF RESULTS TO EVALUATION
OF DELISTING PETITION 7
5.0 GETTING STARTED: WALK-THRU WITH SCREENS 8
5.1 HOW DO I START THE DRAS SOFTWARE? 8
5.2 WHAT ARE THE FEATURES OF THE DRAS USER-INTERFACE? 8
5.3 ANALYSIS INPUT 9
5.3.1 Facility Information Tab 9
5.3.2 Waste Management Unit Tab 10
5.3.3 Chemical Input Tab 11
5.4 ANALYSIS RESULTS 12
5.4.1 Delisting Results Tab 13
5.4.2 Chemical-Specific Results Tab 15
5.4.3 Cumulative Results Tab 16
5.4.4 Summary of Results Tab 17
5.5 PRESENTATION OF RESULTS REPORTS 17
6.0 SUPPORTING INFORMATION 18
6.1 JUSTIFICATION AND DOCUMENTATION OF
PARAMETER VALUES 18
6.2 U.S. EPA REGION 6 18
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1.0 INTRODUCTION
This User's Guide has been developed as part of the U.S. Environmental Protection Agency (EPA) Region 6
Hazardous Waste Delisting Program. It has been prepared to assist the user in applying the Region 6
Delisting Risk Assessment Software (DRAS) to determine whether a waste qualifies as not characteristically
toxic for the purposes of delisting (in accordance with Title 40 Code of Federal Regulations (CFR) Parts
260.20 and 260.22 and the Region 6 Delisting Program).
The Region 6 Delisting Program developed this software to compute the risks and hazards associated with
a specific waste stream for which a delisting petition has been submitted. The Region 6 DRAS will assess
the toxicity of a petitioned waste by calculating: (1) chemical and waste volume-specific screening exit
values, and (2) cumulative carcinogenic risks and hazard indices (for non-carcinogens).
1.1 OBJECTIVES
The objectives of the User's Guide are: (1) to provide general information about the Region 6 DRAS, (2)
to provide step-by-step instructions on using the software and interpreting the results of the risk assessment,
and (3) to troubleshoot difficulties commonly encountered in installation and operation of the software. This
information is intended to assist regulatory authorities, petitioners, and decision makers in the hazardous
waste delisting determination process.
Users are directed to the Delisting Technical Support Document (DTSD) for detailed background information
about the algorithms, equations, and the dilution-attenuation factors (DAFs) used in the risk assessment. The
DTSD is available as a WordPerfect 6.1 file on the compact disc (CD).
Petitioners are directed to the Region 6RCRA Delisting Program Guidance Manual for the Petitioner (U.S.
EPA, 1996) for additional information necessary to satisfy the information requirements of a complete
delisting petition.
1.2 BRIEF OVERVIEW OF THE SOFTWARE
This software will assess the carcinogenic risk and noncarcinogenic hazard associated with a petitioned
waste's disposal to either of two types of waste management units (WMU): 1) landfills and 2) surface
impoundments. The software prompts the user to enter waste information which should be available in the
delisting petition. Once all the general waste information and the chemical specific constituent concentration
data have been entered, the program will perform screening and cumulative risk and hazard calculations.
The screening risk evaluation will provide the user with Toxicity Characteristic Leachate Procedure (TCLP)
and total waste constituent concentrations associated with a IxlO"5 carcinogenic risk level and a hazard
quotient of 0.1 for the most sensitive exposure pathway. These TCLP and total values may be used as the
maximum allowable waste constituent concentrations for a multi-year standard exclusion (delisting). If the
waste constituent concentration exceeds these risk-based levels, the waste may not qualify for a multi-year
exclusion under 40 CFR §§260.20 and 260.22.
The cumulative risk assessment will provide the user with an overall carcinogenic risk and noncarcinogenic
hazard index (HI) for the petitioned waste as a whole, summing risks associated with each exposure pathway
for a given constituent and then summing risk for all waste constituents. The assessment will also provide
the user with the cumulative carcinogenic and noncarcinogenic risks associated with a specific waste
constituent. If the waste exceeds the risk-based levels outlined in the DTSD, the waste may not qualify for
exclusion under 40 CFR §§260.20 and 260.22. The methods and data used in: 1) the determination of media
waste concentrations at the point of exposure; 2) the risk assessment algorithms is outlined and referenced
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in the DTSD
To obtain a copy of the DTSD, please contact:
Michael G. Morton, Ph.D.
Multimedia Planning and Permitting Division (6PD-O)
U.S. EPA Region 6
1445 Ross Avenue
Dallas, Texas 75202
214/665-8329
morton.michael@epa.gov
To avoid misinterpretation, the results of the screening analyses and the cumulative risk analyses are
displayed to the user on separate screens. The screening results display each waste constituent that exceeds
the screening risk levels, along with the exposure pathway for which the exceedance was determined and the
waste concentration (TCLP and total) that would allow the constituentto pass the screening levels (i.e., 1x10"
5 for carcinogens and 0.1 hazard quotient for non-carcinogens).
The cumulative risk interface screens provide: 1) the carcinogenic risk and noncarcinogenic hazard quotient
for each pathway for a given constituent; 2) the cumulative risk and HI for all exposure pathways of a
specific waste constituent; 3) the cumulative risk and hazard index (HI) summed for all waste constituents;
4) identification of chemicals that exceed their soil saturation value; and 5) identification of chemicals that
exceed Toxicity Characteristic (TC) Rule regulatory values.
The user may also enter the detection limit (DL) value associated with a given waste constituent and the
program will determine the risk and hazard associated with a fraction of the waste constituent DL value. The
default fraction used in the risk assessment is 0.5 (50% of the detection level). The program will track waste
constituent risks associated with actual measured concentrations and those risks associated with DL values.
1.3 USING THE DRAS SOFTWARE IN SEVEN EASY STEPS
Step 1: Installation (Windows 95). To install the DRAS software, insert the installation CD into
the drive. If your machine has AUTORUN enabled, a. DRAS installation screen will be displayed.
Click on the "Install Delisting Risk Assessment Software" button to install the DRAS, then follow
the on-screen instructions. If AUTORUN is not enabled, then, from the start menu, select RUN.
Enter the drive letter for your CD drive followed by SETUP.EXE in the dialog box or click
"Browse" and click on the file SETUP.EXE on the CD drive. Then follow the instructions. (For
more information, see Section 3.0).
Step 2: Open DRAS (Windows 95). To open the DRAS software select "Programs" from the Start
menu and then select "Delisting Risk Assessment Software" (see Section 5.1). On initial start-up
the DRAS presents a series of introductory screens describing the program. Click "Next" until
reaching the last screen, then click "Finish" to enter the analysis input part of the program. The
introductory screens can be turned off by checking the box at the bottom of the analysis input screen.
Step 3: Enter information for record keeping. To enter information for record keeping purposes,
click the "Facility Information" tab located at the top of the data entry screen (see Section 5.3.1).
Step 4: Enter facility-specific information about the WMU. To enter information about the
WMU, click on the "Waste Management Unit" tab. Then select the WMU type ("Landfill" or
"Surface Impoundment") and enter the WMU properties ("Waste Volume" and "Active Life") (see
Section 5.3.2).
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Step 5: Enter chemical-specific information about a waste petitioned for delisting. To enter
chemical-specific information about a waste, click on the "Chemical Input" tab. Then select the
desired chemicals from the chemical list. After selecting the chemicals enter the maximum TCLP
concentration (mg/L), maximum total concentration (mg/kg), and, if necessary, its DL (see Section
5.3.3).
Step 6: Run analysis. To obtain detailed risk assessment results, click on the "Run
Analysis" tab at the bottom of the screen. Clicking on the "Run Analysis" button generates the
Analysis Results screen comprised of four tabs: Delisting Results, Chemical-Specific Results,
Cumulative Results, and Summary of Results (see Section 5.4).
Step 7: Print and/or save results. To print the risk assessment results, click on the "Print Results"
button at the bottom of the Analysis Results screen, and then select the desired reports to print. To
save the analysis results, click on the "Save Analysis" button at the bottom of the Analysis Results
screen, and then choose the desired location and filename (see Section 5.5).
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2.0 SYSTEM REQUIREMENTS
This section summarizes the minimum and recommended installation and operating requirements.
2.1 MINIMUM SYSTEM REQUIREMENTS
The minimum system requirements for installing and running this software are as follows:
PC: 486 CPU
Operating System: Windows 3.11
System Memory: 16 Mb RAM
Disk Storage Space 6 Mb hard-disk space
Other: CD-ROM
2.2 RECOMMENDED SYSTEM REQUIREMENTS
The recommended system requirements for installing and running this software are as follows:
PC: Pentium 133 MHZ
Operating System: Windows 95
System Memory: 32 Mb RAM
Disk Storage Space 30 Mb hard-disk space
Other: CD-ROM
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3.0
INSTALLATION
The U.S. EPA Region 6 DRAS is installed from a CD installation disk. To install the software, the user
should perform the following steps:
United States
t Environmental Protection Agency
"...to protect human health and to safeguard the natural environment..."
WELCOME! This is the first step in setting up EPA Region 6's Delisting Risk
Assessment Software version 1.1, known as DRAS for short. In order for DRAS to run
properly, three steps must be performed in the setup process. These steps are:
1.
Install A dob e1 s A crob at Re ader 4.0 s o that the D elisting T e chnic al Supp ort
Document can be accessed from within DRAS;
Install the Microsoft Help software to permit access to the DRAS Help files,
and finally,
Install DRAS to begin performing Risk Assessments of your waste.
Acknowledgements il
Install Acrobat Reader
Install Microsoft Help
Install Delisting Risk Assessment Software
Close all other applications.
Insert disk into the CD drive.
If your machine has
AUTORUN enabled, an
installation screen will load
automatically from the CD.
Click the "Install Delisting Risk
Assessment Software" button to
install the DRAS If your
machine does not have
AUTORUN installed, then, to
begin the installation process:
For Windows 3.11 users: from
the "File" menu, select "Run."
For Windows 95 and NT users:
from the "Start" menu, select
"Run."
Click the "Browse" button and navigate to the CD drive. Click on the setup.exe file and
then click the "OK" Button.
On the "Welcome" screen, click "OK."
Select the destination directory on your hard-drive where this software is to be installed and
click on the "Installation" button.
When the installation is complete, click on the "OK" button to exit the installation process.
For Windows 3.11 users, the program can be started by double-clicking on the Delisting program group, and
then double-clicking on the Drasvl.exe file.
For Windows 95 users, the program can be started by selecting "Programs" from the "Start" menu (on the
Windows tool bar at the base of your screen). Then select "Dras" from the list of available programs.
If you are experiencing difficulties installing the DRAS and are linked to a network version of Windows, it
may be necessary to use your local version of windows. Check with your local network administrator to
determine the best option for installation.
If you are running virus scan software, it may be necessary to close the virus scan software prior to installing
the DRAS
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4.0 BRIEF OVERVIEW OF RUNNING THE SOFTWARE
The Region 6 Delisting Program has developed this Windows-based DRASto calculate delisting levels and
to perform a cumulative assessment of the total carcinogenic risk and noncarcinogenic hazard associated with
the disposal of the petitioned waste.
4.1 DELISTING LEVEL ANALYSIS VERSUS RISK AND HAZARD ANALYSIS
The DRASperforms two types of analyses: (1) a delisting level analysis and (2) a cumulative risk and hazard
analysis. The results of these analyses may be viewed on screen, imported into word processing documents,
or printed in document-ready form. The results of the delisting level analyses are used in the evaluation of
multi-year delisting petitions, whereas the results of the risk and hazard analyses are used in the evaluation
of one-time delisting petitions.
4.2 DELISTING LEVEL ANALYSIS
The delisting level analysis computes chemical-specific delisting levels or "exit values" for multi-year
delistings. These delisting levels are the maximum allowable total constituent concentration in the waste and
the maximum allowable waste leachate concentration. Delisting levels are calculated using default values
for the target risk and hazard quotient of 10~5 and 0.1, respectively. The default target risk and hazard
quotient values can be changed by the user, but this will impact the magnitude of the resulting delisting
levels. EPA Region 6 requires use of the default values in delisting petitions.
Because toxicity is only one of the waste characteristics which are examined in a delisting petition, a waste
which does not exceed its delisting levels is not automatically delisted. A waste that contains constituents
at concentrations that exceed their delisting levels may not qualify for delisting.
4.3 RISK AND HAZARD ANALYSIS
The cumulative risk and hazard analysis computes the cumulative carcinogenic risk and noncarcinogenic HI
of a waste petitioned for a one-time delisting to determine if the risk exceeds a 10"4 risk and/or if the hazard
exceeds a 1.0 HI.
4.4 REQUIRED INPUT
To calculate the delisting levels and the potential risks associated with a particular waste stream petitioned
for delisting, specific information about the petitioned waste is required. EPA Region 6 requires the
petitioner to input the following waste-specific information into the DRASto estimate risks associated with
potential exposure to the petitioned waste stream:
The maximum annual volume of the petitioned waste for a multi-batch delisting petition or
the maximum total waste volume for a one-time delisting,
The rate at which leachate flows from a surface impoundment into the subsurface,
The maximum total concentration of each chemical constituent in the petitioned waste,
The maximum TCLP concentration (estimated leachate concentration) of each chemical
constituent in the petitioned waste, and
The number of years the petitioned waste is projected to be generated.
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4.5 OUTPUT
Delisting levels are presented on the tab entitled DelistingResults. These delisting levels are the maximum
allowable concentrations which can be present in the waste without exceeding the defined risk level (10~5)
or HI (0.1). If the concentration in the petitioned waste exceeds the delisting level for a given waste
constituent, the delisting level is reported in the table on the Delisting Results tab; otherwise, "N/A" is
reported in the table. Further, instances of a chemical's total waste concentration exceeding the 10,000
mg/kg delisting ceiling are indicated in the results. Also, when a chemical's TCLP concentration exceeds
its TC Rule regulatory value (see CFR §261.24(a), Table 1), this is incicated in the results. Finally, when
an organic chemical's calculated delisting level is greater than its soil saturation value (given in the
Appendices of the DTSD), this is indicated in the results.
The complete results from the risk/hazard analysis are presented on the Chemical-Specific Results tab and
the Cumulative Results tab and are summarized on the Summary of Results tab. In the risk and hazard
analysis, first the potential risk and hazard posed by disposal of the petitioned waste is calculated. Then the
calculated total risk level for the petitioned waste is compared to the standard risk level of 10"4 and the
calculated total HI for the petitioned waste is compared to the standard HI of 1.0.
4.6 APPLICATION OF RESULTS TO EVALUATION OF DELISTING PETITION
If any of the delisting levels are exceeded, the waste may not qualify for delisting. However, because toxicity
is only one of the waste characteristics which are examined in a delisting petition, a waste which does not
exceed the delisting levels is not automatically delisted.
A petitioned waste whose cumulative carcinogenic risk (as calculated in DRAS risk and hazard analysis)
exceeds the value of 10~4 may not be a candidate for delisting.
Exceeding a hazard quotient of 1.0 (as calculated in DRAS risk and hazard analysis) does not necessarily
indicate that the petitioned waste should not be delisted. Not all noncarcinogenic hazards are additive (U.S.
EPA, 1989). If the HI for a petitioned waste exceeds 1.0, the compounds should be segregated by the type
of effect induced and the mechanism of action. Separate hazard indices could then be derived for each target
organ(s) or mechanism of action. This analysis is not a simple process and should only be performed by a
qualified toxicologist. The user is referred to the Region 6 DTSD for additional information.
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5.0 GETTING STARTED: WALK-THRU WITH SCREENS
5.1
HOW DO I START THE DRAS SOFTWARE?
To use the program for the first time, you must install the software from the CD to the hard-drive (see Section
3.0).
For Windows 3.11 users, the program can be started by double-clicking on the DRAS group, and then double-
clicking on the Drasl.exe file.
For Windows 95 users, the program can be started by selecting "Programs" from the Start menu (on the
Windows tool bar at the base of your screen). Then select the "Dras" program from the list of available
programs.
5.2 WHAT ARE THE FEATURES OF THE DRAS USER-INTERFACE?
This software is optimized to work with the Windows 95 operating system, but is also backward compatible
with Windows 3.11. The software is likely to be compatible with the Windows 98 operating system, but has
not been tested in this setting. The DRAS user interface is designed to operate similar to other Windows-
based programs. At the very top of the screen is a title bar which displays the software title. Directly below
the title bar is the main program menu. The user can select among the following menu items: "File,"
"Detection Limits," and "Help." General file
operations such as open and save can be accessed by
clicking on the "File" menu. The user can display the
list of DLs for all constituents by clicking on the
"Detection Limits" menu (note: close the "Detection
Limits" menu to bring back the user-interface screen).
The user can access the User's Guide, get information
about the software, or re-display the introductory
screens by clicking on the "Help" menu.
File Detection Limits Net
Facility Information f Waste Management Unit J
Region 6 Delisting Risk Assessment Program
Delisting Petition ID Number
i
\\\tD STjQ-f
\^-V * i t^-^ Facility Identification (Facility N ame, L
Chemical Input
ocation, etc.)
* irftfBft. ^ t '
^ aJF^Sk -T 1
£ ^" ^ y |
\0 Batch Identification
fy vW" DaiB ef lA!ssle Da
"\Jflj -rcCj Sample Ana^sis Ris
Name of User
e of Delisting
< Assessment
10/30/1998
i
How do I navigate through the DRAS software?
The user interface is set up as a series of Windows-
based screens and tabs through which the user
navigates to enter data and view results. The user can
page through the program using two different methods: 1) by clicking on the command buttons at the bottom
of the screen, or 2) by clicking on one of the labeled tabs located at the top of the data entry and results
screens. These tabs allow the user to:
Enter descriptive information about the waste being evaluated for delisting
Select the waste management scenario and waste volume
Select waste constituents and enter leachate and total waste concentrations
Print reports and save, open, and edit delisting files
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introduction Should Not Appear Agas
How do I get HELP if I have a problem or a question?
Help can be accessed by clicking on the pull-down "Help"
menu screen and then selecting "Help Definitions"or by
clicking on the "Help Definitions" button on the lower right of
the screen. The "Help Definitions" selection presents the user
with a screen containing links to help topics, a searchable index,
and an option to print the "Help" topic text.
The first time the DRAS is run, a series of screens with
introductory information is displayed. After reading this
information, the user can click in the check-box at the bottom
of the screen to prevent these introductory screens from being
displayed the next time the program is run. This introductory
information can be viewed at any time by choosing "Show
Introduction Screens" from the pull-down "Help" menu. Also,
the User's Guide can be viewed from the pull-down "Help" menu. Finally, the pull-down "Help" menu
includes an option for enabling the DL check screen when entering chemical concentrations.
5.3 ANALYSIS INPUT
This section of the DRAS is designated for the input of pertinent facility information, waste-specific
information, and chemical-specific information about a petitioned waste. There are three interface screens
in this section of the DRAS. 1) Facility Information, 2) Waste Management Unit, and 3) Chemical Input
5.3.1 Facility Information Tab
Are the inputs on the Facility Information screen necessary?
The Facility Information screen allows the user to enter information about a delisting petition analysis.
While the inputs on this screen are not required to perform an analysis, this screen allows the user to enter
information that is necessary for record-keeping. In addition, this information entered by the user is printed
on all DRAS reports. The user should enter the following information in the appropriate text box:
Delisting Petition ID Number Internal tracking number forthe delisting petition which is being analyzed
in the DRAS. To facilitate record keeping, each waste petitioned for a RCRA exclusion (delisting) should
be assigned a unique number. We recommend that the ID number incorporate the EPA region number and
year of the petition. For instance, ID# R6-98-001 could be the ID number for the first delisting petition
received in Region 6 during 1998.
Facility Identification The name and address of the facility petitioning for the delisting.
Batch Identification Descriptive information about the batch of waste being analyzed. This information
is useful for distinguishing between several waste streams at the same facility.
Date of Waste Sample Analysis Date the petition analysis was performed. This information is useful for
internal record keeping.
Name of User Person who is performing the delisting risk assessment. Again, this information is useful
for internal record keeping.
Throughout the DRAS program, the facility name and petition identification number are displayed on-screen
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for the user's convenience and so that a printed copy of an individual screen will include identification of
the waste being evaluated.
5.3.2 Waste Management Unit Tab
A waste petitioned for a RCRA hazardous waste exclusion (delisting) is expected to be disposed of in a
WMU. The Waste Management Unit screen allows the user to enter facility-specific information about the
WMUwhere the waste is disposed. The DRASuses waste information entered on this screen to perform the
risk assessment. The information that can be entered is explained below.
What types of WMUs can I select?
WMU The DRAS predicts risks associated with the disposal of petitioned wastes for two types of WMU?,.
Landfill and Surface Impoundment. A Landfill scenario should be selected to assess the potential risks
associated with the disposal of solid wastes petitioned for a RCRA exclusion (delisting). The Surface
Impoundment scenario should be selected to assess the potential risks associated with the disposal of non-
solid wastes petitioned for delisting. If the user selects a landfill as the WMU, only the annual waste volume
must be entered. If the user selects a surface impoundment as the WMU, both the annual waste volume and
flow rate must be entered.
WMU Properties Includes waste volume, facility active life, and type of delisting petition.
Waste Volume The annual volume of waste to be petitioned for a RCRA exclusion (delisting).
Type of Delisting Petition The choice of One-time batch or Multiple-year batch determines whether or
not a value for the active life of the delisting must be entered. If the delisting petition is for a one-time batch
delisting, the user should select the One-time batch option button. For a One-time batch, the default value
of Active Life is one year, and the Active Life input box will be grayed out. If the waste to be delisted will
be disposed of in multiple batches over more than one year, the user should select the Multi-year batch
option button. Selecting this option button will activate the Active Life input box where the user should input
the number of years that the WMU is expected to accept the
petitioned waste.
Fie Oeiedion Limits Help
_] Waste M,
R! * HO Facto
F.I I Faclor il pE.05
Active Life Refers to the active life of the delisting
petition with regard to the waste entering the WMU. The
default value for a multi-year delisting is 20 years and the
default value for a one-time delisting is one year, however,
the user may input another value, as appropriate. For a
multi-batch delisting, a facility is expected to have multiple
batches of waste delisted over an extended period of time.
Therefore, 20 years is selected as a reasonable maximum
value for the facility operational life. The default value for
a one-time delisting is one year since the waste to be delisted will be disposed into the WMU as a one-time
batch.
Flow Rate The rate at which leachate flows from the bottom of the surface impoundment (including any
liner) into the unsaturated zone. This value is determined by the depth of the surface impoundment, the
hydraulic characteristics of the liner or sludge at the base of the impoundment, and the depth and
hydrogeological characteristics of the sediments comprising the unsaturated zone.
Petition ID and Facility Name The Petition ID and Facility Name are displayed here as a reference for
the user. These data can only be changed on the Facility Information screen, as described above.
10
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5.3.3 Chemical Input Tab
The Chemical Input screen allows the user to enter chemical-specific information about a waste petitioned
for delisting. The user first selects the chemicals that were detected in the petitioned waste and then inputs
the Maximum TCLP Concentration and Maximum Total Waste Concentration for each selected chemical.
The user may elect to enter concentrations below the DL in the petition data. The user indicates if a chemical
is below the DL by clicking in the DL column for the specified chemical. The user also has the option to add
a new chemical to the list if the desired chemical is not in the list or if the user does not think that the
chemical properties are appropriate for the petitioned waste.
How do I select chemicals present in the petitioned waste?
List of Chemicals There are four ways to choose chemicals to be analyzed:
1) Begin typing the chemical name in the "Enter Chemical Name" box and if the chemical is found, hit
the "Enter" key;
2) Begin typing the chemical CAS (Chemical Abstracts Service) number in the "Enter Chemical CAS
Number" box and if the chemical is found, hit the "Enter" key;
3) Scroll through the list of chemicals and click in the box of each chemical to be analyzed, then click
the "Select Checked Chemicals" button;
4) Scroll through the list of chemicals and double click on each chemical to be analyzed.
If the user types in the chemical name or CAS number in the corresponding textbox, the program will then
search the list of chemicals for the closest match to the typed value. Once the correct chemical is
highlighted, the user can either double-click on the chemical or hit the "Enter" key to accept the chemical.
The user should be aware that since some chemicals have more than one name, it is possible that the program
may not find the correct chemical based on a search by chemical name. Therefore, if a name search is
unsuccessful, the user should search by CAS number or scroll through the list of chemicals to find the desired
chemical. Please note that the user also has
the option to add a new chemical to the list
with user-defined properties.
What if I suspect that a certain chemical
is present in my waste, but at a
concentration below the DL1
Often the delisting petition will contain
waste sampling results that report non-
detect values for a number of the chemicals
analyzed. The non-detect concentration
may be reported as the method detection
limit (MDL) or as the estimated
quantitation limit (EQL). For the purposes
of this discussion, the concentration
reported as non-detect will be the DL.
Several variables influence the DL for a
chemical, including the instruments used,
the waste matrix, and the analytical test
method. In some cases the reported DL for
a chemical may exceed its delisting level at
the target risk level. In such a case, the user may wish to discuss this issue with the lab to find out if there
is another available analysis method with a lower DL.
I, Analysis Input Region 6 Delisting Risk Assessment Program BIB
[ile Detection Limits Help
Facility Information | Waste Management Unit Chemical Inpul
Enieiing Chemicals
There are four ways to choose chemicals to be analysed:
1) Begin typing the chemical name in the "Enter Chemical
Name" box and if the chemical is found, hit the "Enter"
key;
2) Begin typing the chemical CAS number in the "Enter
Chemical CAS Nurnber"bo}: and if the chemical is found, hit
the "Enter" key;
3) Click m the boxes of the chemicals) to be analyzed, click
the "Select Checked Chemicals" button, and then enter the
concentrations ;
4) Double clack on the chemicals) to be analysed and then
enter the concentrations.
Iron 17439896} _*]
KobuM alcohol {78831}
Lophorone {78591}
r'epme {143500}
* gitf Sciavji^^^^^^a _i
Magnesium {7439954}
Manganese {7433965}
Mercury {7439976} J
inter Chemical Name
Select
r L rir- u L Checked
Enter CAS Number ChealK^
r, -I.LAI A CAS Maximum TCLP m Maximum Total m
Chem,calS to be Analyzed N(jmbef Concentration (mg/L) DL Concentration (mg/kg) »L
Lead 7439921 Enter Concentration No Entei Concentration No
To edit concentration, click on cell and enter new value.
Italics signify that the concentration for that constituent is a detection limit, not a measured concentration.
Create Chemical Delete Row Run Analysis Help
11
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When a chemical is selected, and provided that the DL check screen option is turned on, the DRAS will
present a screen that asks the user whether the concentration that will be entered for the chemical is to be
treated as a DL or a measured value. Entering a DL will cause results for that chemical to be shown (on-
screen and in printed reports) in italics throughout the rest of the DRAS analysis. Also, the DRAS determines
the risk and hazard associated with a fraction of a chemical's DL. The default fraction used in the
assessment is 0.50, so, in conducting the risk and hazard assessment for a chemical whose waste
concentration (TCLP or total) has been entered as a DL, the DRAS first multiplies the waste concentration
by 0.50, then evaluates the risk and hazard. Further, all risk assessments are conducted twice: once including
those chemicals specified with concentrations that are DLs and once omitting them. This enables the user
to know if these non-detects are driving the results of the risk assessment. Again, if the risk is impacted by
the non-detects, the user may wish find out if there is another available analysis method with a lower DL.
The DL check screen option is accessed from the "Help" pull-down menu.
How do I enter the TCLP and total chemical concentrations for each chemical?
As the user selects chemicals and either hits the "Enter" key, double-clicks, or hits the "Select Checked
Chemicals" button, a table is built at the bottom of the screen, each line of which specifies a selected
chemical. The table cells below the column labeled Maximum TCLP Concentration are used to enter the
waste TCLP concentration. To enter a value, click on the cell for a chemical and type in the concentration.
Likewise, the cells below the column labeled Maximum Total Concentration are used to enter values for
that parameter. If the laboratory analysis method reports a non-detect, the user should enter the DL as the
concentration.
Can I edit the concentration values of a chemical?
Edit Constituents) If the user accidentally enters an incorrect TCLP and/or Total Waste Concentration,
these values can be edited. To edit these values, the user should click on the cell containing the incorrect
value, then enter the new value. The user may also click on the "Delete Row" button to remove a chemical
from the table.
How do I perform the risk assessment for the petitioned waste?
After entering all the waste- and chemical-specific values, the user should click on the "Run Analysis" button
to perform the risk assessment for the petitioned waste.
5.4 ANALYSIS RESULTS
This section of the DRAS provides the user with detailed risk assessment results for the petitioned waste.
The Analysis Results screen is comprised of four tabs: Delisting Results, Chemical-Specific Results,
Cumulative Results, and Summary of Results. Each tab contains a different form of the results of the
delisting analysis. The tabs and the information found on each of these tabs are explained below.
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5.4.1 Delisting Results Tab
The Delisting Results tab is the first screen in the Analysis Results Section of the DRAS. This screen lists
all chemicals whose TCLP and/or Total Waste Concentration exceed the delisting levels as computed by
the risk equations. The first and second columns of the table show the Chemical Names and CAS numbers,
respectively, for chemicals that exceed the delisting levels. The third column identifies the pathway and the
fourth shows the resulting Maximum Allowable TCLP Concentration (i.e., the limiting TCLP
concentration). The fifth column shows fas Actual TCLP Concentration of the chemical. The sixth column
shows the Maximum Allowable Total Concentration (i.e., the limiting Total Waste Concentration) of the
chemical and the seventh column shows the Actual Total Concentration of the chemical.
The delisting level is the maximum allowable concentration of a waste constituent in a petitioned waste that
will not exceed the target risk level for that compound. For multi-year standard delistings, each waste
constituent in a petitioned waste must not exceed its delisting level. The delisting level is generated for each
Exceeding Pathway assessed by the DRAS. The DRAS selects a limiting delisting level for the total value
and the TCLP value for each waste
constituent. The delisting level for
the total waste constituent value is
called the Maximum Allowable Total
Concentration. The delisting level
for the TCLP waste constituent value
is called the Maximum Allowable
TCLP Concentration.
What are the various exposure
pathways assessed in DRAS?
The DRAS assesses the potential
adverse effects associated with the
release and subsequent exposure of
waste constituents in a petitioned waste from a WMU. Exposure may occur through contact with various
contaminated media. The following exposure pathways (Exceeding Pathways) are assessed in the DRAS.
For releases to ground water:
ingestion of contaminated ground water
dermal absorption while bathing in contaminated ground water
inhalation of volatile constituents emitted from contaminated ground water during showering
Deftsting Results f Chemical-Specific Results Cumulative Results Summary of Results
Petition ID Facility Name
TEST-98-001 JHydroGeoLogic, Inc.
CAS Exceeding AII.....^^^^! p Actual TCLP Aii^^fr^t.j Actaal Total
7440382 GW 4.13E-Q1 1 75E+00 N/A 5 QQE+04
Al5etUE listen
7440382 SWAt-utp IT .'A 1 7"E+OQ 3 40E-01 5 OOE+04
Aiseiuc Ecolo-icial
7440382 EWChr^juc H.'A 1 75E+00 1 jOE-01 5 OOE+04
7440382 Soil H.'A 1 75E+00 1 40E-03 5 OOE+04
<'7('£>i &r WA L93B-0! L20S+07 L2SE+Q7
Italics signify that the concentration for that constituent is a detection imit not a measured concentration.
The values in the "Maximum Allowable TCLP Concentration" and the "Maximum Allowable Total Concentration" are the maximum wa
concenhations which can be permitted withoul exceeding the defined cancer risk or hazard quoisenl levels set for the Delisting Level
given waste constituent. See Help for additional infofmation on the allowable tisklevei used to calculate a wasle constituent's "Delisti
Levels" (T CLP and Total).
3
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3
f GaBack il PrintReports I Help SaveAnalysis j
For releases to surface pathways:
ingestion of contaminated surface water
ingestion of contaminated fish
ingestion of contaminated soil
inhalation of contaminated air
How are the delisting levels calculated?
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For all standard multi-year delistings, the target risk level is used to calculate the delisting levels for a waste
constituent. The target risk level for carcinogens is set at 10~5 and for noncarcinogens the target is set at a
hazard quotient of 0.1. Additional technical information on risk levels is available in Chapter 4 of the DTSD.
What role does the 10,000 ppm delisting ceiling play in the delisting analysis?
Using standard chronic risk assessment algorithms, the DRASgenerates delisting levels, which are protective
of exposure to the receptor for the defined exposure pathways. However, the delisting levels generated in
this manner for certain constituents can be extremely high in absolute concentrations (approaching that of
a pure compound). Under certain circumstances, the generated delisting levels may not be the appropriate
waste management concentration limits for the prescribed WMU. For these reasons, there is a need to assess
the reasonableness of high concentration limits developed from the chronic risk models, particularly for
liquid and volatile organics. The issue is a general policy concern for all chronic risk analyses, and
resolution is beyond the scope of the DRAS or this user guide. However, the DRAS has been programmed
to identify total waste constituents predicted at nominally high concentration levels (10,000 ppm or 1% by
weight or greater). Delisting levels in excess of 10,000 ppm are highlighted in red text on the "Results"
screen of the DRAS. When the DRAS computes a delisting level that exceeds 10,000 ppm, the petitioned
waste containing constituents in excess of this value will be reviewed on a case-by-case basis. In the DRAS,
the delisting levels (exit values) are not altered to reflect this ceiling review. The DRAS provides the user
with the calculated delisting level, based on the waste constituent concentrations, the waste volume and the
risk level selected by the user.
How are soil saturation values, Maximum Contaminant Level (MCL) values, and TC Rule regulatory
values used?
Soil saturation values (see Appendix A of the DTSD) represent the contaminant concentration in soil at
which the adsorptive limits of the soil particles and the solubility limits of the available soil moisture have
been reached. Above this concentration, pure or free-phase compound is expected in the soil. If the soil
saturation limit is exceeded, formation of a nonaqueous phase liquid (NAPL) plume is possible for the
organic constituents. If NAPLs are present, significant contaminant migration may occur within this NAPL
phase, which is not accounted for in the EPA Composite Model for Leachate Migration with Transformation
Products (EPACMTP) fate and transport model. Hence, calculated delisting values may not be accurate.
The DRAS compares soil saturation values with calculated delisting levels and notifies the user when a waste
constituent's total delisting level exceeds its soil saturation value. When the DRAS calculates a delisting
level greater than the calculated soil saturation, the delisting manager should consider setting the delisting
level equal to the soil saturation.
In addition to calculating a waste constituent's delisting level for the ingestion of ground water based on the
pre-selected target risk level, the DRAS calculates the waste constituent's delisting level for the ingestion
of ground water where the ground water concentration is set at the constituent's MCL. In some cases, the
waste constituent's ground water ingestion delisting level based on the MCL will be less conservative than
that calculated according to the selected risk level. When the DRAS indicates that ground water ingestion
is the limiting ground water pathway, the user has the option of considering either of the ground water
ingestion pathway delisting levels: the risk-based Maximum Allowable TCLP Concentration or the
Maximum Allowable TCLP Based on MCL.
The TC Rule was promulgated in March, 1990 (55 FR 11798). This rule established regulatory levels for
40 nonhydrolyzing or mildly hydrolyzing constituents. A solid waste exhibits the toxicity characteristic if,
using the TCLP, the extract from a representative sample contains any of the 40 TC Rule constituents at
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concentrations equal to or greater than the regulatory level (published at 40 CFR §261.24(a) and given in
Table 4-1 oftheDTSD). These regulatory levels are not to be exceeded. Because the DRAS generates exit
levels using different modeling and exposure scenarios, delisting levels for these 40 constituents may be
above or below the TC Rule regulatory levels. Therefore, the DRAS compares a waste constituent's delisting
level forthe TCLPwaste constituent concentration, called the Maximum Allowable TCLP Concentration,
with the waste constituent's TC Rule regulatory level. If the Maximum Allowable TCLP Concentration
exceeds the TC Rule regulatory level, the DRAS notifies the user of the TC Rule exceedance.
How are dioxin cogeners handled in the DRAS1
U.S. EPA Region 6 recommends that a risk assessment for all dioxin cogeners be completed by calculating
the Toxicity Equivalent Quotient (TEQ) for 2,3,7,8-tetrachlorodibenzo(p)dioxin (TCDD). The TEQ is
calculated by converting the dioxin congener concentrations to a 2,3,7,8-TCDD dioxin concentration using
Toxicity Equivalent Factors (TEF) for all 17 dioxin cogeners. To assess the risk to a mixture of dioxin
cogeners reported in a delisting petition using the TEF procedure: 1) review the delisting petition for all
polychlorinated dibenzo(p)dioxin (PCDD) and polychlorinated dibenzofuran (PCDF) analytical
determinations from the sample; 2) multiply the congener concentrations in the sample by the TEFs listed
in Section 4.2.5 of the DTSD to express the concentration in terms of 2,3,7,8-TCDD TEQs; 3) sum the
products calculated in Step 2 to obtain the total TEQ for the delisting sample and; 4) use the delisting sample
total TEQ as the sample concentration of 2,3,7,8-TCDD to be entered into the DRAS under the name
TCDDioxin, 2,3,7,8- or CAS number 1746016.
5.4.2 Chemical-Specific Results Tab
Chemical-Specific Results is the second interface screen in the Analysis Results section of the DRAS. The
user is provided with a chemical-by-chemical summary of the risk and hazard analysis of each waste
constituent entered into the DRAS. The chemical-specific summary includes the Allowable Total
Concentration andAllowable TCLP Concentration for each Exposure Pathway and the actual carcinogenic
risk or noncarcinogenic hazard
quotient predicted from exposure
to each Exposure Pathway. The
section also presents the
Maximum Allowable Total
Concentration and Maximum
Allowable TCLP Concentration
for a given waste constituent. The
chemical name and CAS number
are shown at the top along with
information to tell the user if the
risk assessment is based on
carcinogenic effects or
noncarcinogenic effects. The two
tables show each Exposure
Delisiing Results ] : Chemical; Specific Results] f Cumulative Result
Summary of Results
Petition ID , . Facility Name
Test-98-001 '' ' j ;';;" ' ;; j HydroGeoLogic, Inc.
Chemical-Specific Results for: CAS Number Carcmogen/Noncarcinogen
(Benzene J71432 jCatcnoge
TCLP Concentration |mg/L] h GQE+03
Exposure Pathway Pathway Allowable TCLP Cone. (rng/L) Actual Risk
GW Ingestion Pathway 4.54E-01 1.72E-02
GW Adult Derma! Pathway 3.34E+QQ 2.54E-03
GW Child Dermal Pathway 9.04E+OQ 1.11E-03
GW Inhalation Pathway 1.20E-01 4.40E-03
Air Volatile Inhalation Pathway 1 .78E+OQ 4.88E-04
Total Waste Concentration [my/kg] j-OoE+bs
Exposure Pathway Pathway Allowable Total Cone, (rng/kg] Actual Risk
SW Ingestion Pathway 2 G6E+07 2.83E-05
An Particuiate Pathway 5 12E+07 5.87E-12
Fish Ingestion Pathway 6 38E+06 1.51E-Q4
Soil Ingestion Pathway 2.62E+05 2.70E-02
Maximum Allowable
TCLP Concentration
(the TCLP D dialing Level)
J1.2QE-01
Maximum Allowable
Total Concentration
(the Total Deling Level)
Maximum Allowable
TCLP base on MCL
J9.00E-02
GoBack 1 PrirtFjeporfs j Heip I SaveAnalysis J
Pathway in column 1, the
maximum allowable concentration in column 2, and the actual risk or hazard quotient in column 3 for TCLP
and Total Waste Concentrations.
How do I see the risk assessment for each chemical?
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The user can click on the "Next" and "Previous" buttons to scroll through the list of chemicals and view the
risk assessment that was conducted for each selected chemical.
5.4.3 Cumulative Results Tab
Cumulative Results is the third interface screen in the Analysis Results section of the DRAS. The
Cumulative Results screen shows the cumulative Groundwater Pathway and Surf ace Pathway risk for each
carcinogenic chemical and the cumulative HI for each noncarcinogenic chemical. If any of these calculations
are based on DL values, the row containing that chemical is shown in italics. These values are then summed
for each chemical to compute the Chemical Cumulative Risk or Chemical Cumulative Hazard Index found
in the last column of the table. Directly below the "Carcinogen" results table, two total risk values are
displayed. The first Petitioned Waste Total Risk value does not include any non-detects, whereas the second
Petitioned Waste Total Risk value does include non-detects that were entered by the user. Likewise, directly
below the "Non-carcinogen" results table is the Petitioned Waste Total Hazard Index, calculated both with
and without the non-detect values.
How are the Risk and HI values calculated?
The Chemical Cumulative Risk value is a measure of the total risk associated with disposal of a carcinogenic
waste constituent. This is computed by summing a waste constituent's carcinogenic risk from each exposure
pathway. Additional technical information on the generation of risk values is available in Chapter 4 of the
DTSD
Delisting Results J Chemical-Specific Results |
Petition ID
iCumujativeJesujli (
Facility Name
Summary of Results
Carcinogens |TEST-98-Oul JH.drc&oLogic, Inc.
r, .... Groundwater Pathway Surface Pathway -., . , n , . . , *(
Chemical Name Cumulative Risk Cumulative Risk Chemical Clat,ve Risk -j
Arsenic 398E-05 317E+QO 3.17E+00
fMn-Avai 1 SST-Of 3 12E+SG 3 12E+8B
DDT, p,p ' t. G4E-B5 20&*Q1 283E+LT!
TrirhhrnpfhttUtm f1 1 ?-] (TTFt ? R7F-HR 7^1P+m 7"=ilF+niLlJ
Petitioned Waste (without Detection Limits] Total Risk = (7 85E +01
Petitioned Waste (including Detection Limits] Total Risk = J4.23E+Q2
Noncarcinogens
r, .... Groundwater Pathway
Lnemicai Name Cumulative Hazard Index
Cadmium 2.42E-05
1 £#&!&£ ffofa/f / S&F-tZ?
Surface Pathway Cherrn
Cumulative Hazard Index Ha
2.11E+04
al Cumulative
2ard Index
2.11E»04
Petitioned Waste (without Detection Limits] Total Hazard Index
Petitioned Waste (including Detection Limits] Total Hazard Index
Go Back 1 Print Reports 1 Help
_| 5.veAn.Ns|
|2.11E*04
|2.14E*04
The Chemical Cumulative Hazard
Index value is a measure of the total
hazard associated with disposal of a
noncarcinogenic waste constituent.
This is computed by summing a
waste constituent's noncarcinogenic
HI for each exposure pathway.
Additional technical information on
the generation of hazard indices is
available in Chapter 4 of the DTSD.
Petitioned Waste Total Risk
(without DLs) is calculated by
summing the petitioned waste's
carcinogenic risk from only those waste constituents whose input TCLP concentration and Total Waste
Concentration were actual measured concentrations (not DLs).
Petitioned Waste Total Risk (including DLs) is calculated by summing the petitioned waste's carcinogenic
risk from all waste constituents. This includes constituents with a measured TCLP concentration and Total
Waste Concentration, and constituents for which the DL was entered as the concentration.
Petitioned Waste Total Hazard Index (without DLs) is calculated by summing the petitioned waste's
noncarcinogenic hazard from only those waste constituents whose input TCLP concentration and Total
Waste Concentration were actual measured concentrations (notZ>Z,s).
Petitioned Waste Total Hazard Index (including DLs) is calculated by summing the petitioned waste's
noncarcinogenic hazard from all waste constituents. This includes constituents with a measured TCLP
concentration and Total Waste Concentration, and constituents for which the DL was entered as the
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concentration.
5.4.4 Summary of Results Tab
Summary of Results is the fourth screen in the Analysis Results section of the DRAS. This screen presents
a summary of the risks and hazards associated with disposal of the petitioned waste. Also, this screen
identifies those chemicals whose waste concentration exceeds their soil saturation value or TC Rule
regulatory level. This screen repeats the facility and user information provided at the beginning of the
analysis along with the total risks and hazard indices displayed in the Cumulative Results screen. The risk
and HI values are calculated both with and without the non-detect values (DLs).
5.5
PRESENTATION OF RESULTS - REPORTS
Can I print and save the results of the analysis?
The results of the analyses performed with the DRAS can be printed to hard copy or saved electronically as
a file. The report form prints out all of the WMU parameters, chemical input values, and the results of the
analysis. The user may click on the "Print Reports" button to printthe reports in the Analysis Results section
of the DRAS. The user also has the option to click on the "Print Preview" button to view the report before
printing the reports. The user selects which reports
to print or print preview by clicking on the boxes
beside the various reports. The user may save a
report as an electronic file by clicking the "Print
Preview" button followed by the "Export" button
(small envelope button). The user may choose which
application to export the electronic file to under
"Format" and if the file will be saved as a disk file,
a Lotus Notes database file, or sent as an email file
under "Destination."
- Print Reports-
Reports to Print
Copies-
" Inputs
' Limiting Pathways/Concentrations
Cumulative Risk and Hazard Quotients
Number of copies: J-j
Print Preview
Print
Cancel
Page/"Printer Setup
6.0
SUPPORTING INFORMATION
This section presents summary information that is required to perform U.S. EPA Region 6 Delisting risk
assessments, or supporting information that can be accessed.
6.1
JUSTIFICATION AND DOCUMENTATION OF PARAMETER VALUES
All values input to the delisting
risk assessment analyses must be
backed up with supporting
documentation including lab
analysis results and other waste
characterization data.
6.2
U.S. EPA REGION 6
Supporting information for EPA
Region 6 Delisting includes this
User's Manual and the DTSD As
Delistinp Results } Chemical-Specific Results
Delisting Results for
(HydroGeoLogic, Jnc
|11 55 Herndon Parkway
JHemdon.VA
Petition ID
|Test-98-OQ1
Performed by
(Tester
Performed on
J1 2/1 7/1 998
Date of Waste
Batch Identification Sample Analysis
| Paint Wassl S tream j 01 /01 ,J1 938
| Cumulative Results f Summary of Results]
Carcinogens
Petitioned Waste Total Cumulative Risk =
Petitioned Waste (ind DLs) Total Cumulative Risk =
Noncarcinogens
Petitioned Waste Total Hazard Index =
Petitioned Waste (ind. DLsj Total Hazard Index =
Chemicals that exceed Soil Saturation Values:
Benzene 71432
Chemicals that exceed TC Rule Values;
Benzene 71432
|518E-Q2
|519E-02
IQ.QQE+QQ
IO.OOE+OO
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stated previously in this document, petitioners are directed to the Region 6 RCRA Delisting Program
Guidance Manual for the Petitioner (U.S. EPA; 1996) for additional information necessary to satisfy the
information and documentation requirements of a complete delisting petition.
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