Innovations in Site Characterization: Case Study: Dexsil L2000 PCB/Chloride Analyzer for Drum Surfaces


United States
Environmental Protection
Agency
        Office of Solid Waste and
        Emergency Response
        (5102G)
EPA-542-R-99-003
May 1999
www.epa.gov
clu-in.org
 r/EPA
innovations in Site
Characterization
Case Study: Dexsil L2000
PCB/Chloride Analyzer for Drum
Surfaces

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                                Table of Contents

Notice	 ii
Foreword 	•	•	*"
Acknowledgments	^
Case Study Abstract	•	v&
Technology Quick Reference Sheet	**•
EXECUTIVE SUMMARY
                                                                                  1
PROJECT INFORMATION	,	 3
       Identifying Information	•	 3
       Background	'.	• • •.	 3
       Project Logistics/Contacts 	 ^

MEDIA AND CONTAMINANTS	, -.-.	•	 5
       Matrix Identification	 5
       Project Geology/Stratigraphy	• 5
       Contaminant Characterization	 5
       Matrix Characteristics Affecting Characterization Cost or Performance	 5

 PROJECT CHARACTERIZATION PROCESS	 5
       Goal of Characterization	•	•	 5
       Sampling Workplan		•	  '
       Quality Assurance/Quality Control Measures 	•	  16

 CHARACTERIZATION TECHNOLOGIES	...21
       Wipe Sampling	•	•	  2*
       Sampling Results and Cleaning Process Performance	•	  23
       Performance of Analytical Technology	  24

 COST COMPARISON	•	  29

 OBSERVATIONS AND LESSONS LEARNED	•	  31

 REFERENCES	 32

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                                     List of Figures

Figure 1: Process Control Chart for Free Release	,	 11
Figure 2: Process Control Chart for Metal Recycling	 11

                                     List of Tables

Table 1. Analytical Data Quality Indicators (DQIs), Measurement Quality Objectives (MQOs), and
       Corrective Actions for Dexsil field method	 18

Table 2. Performance characteristics of the Dexsil L2000 PCB/Chloride analyzer based on the
       EPA/DOE ETV study and DOE criteria for selecting a field method to monitor the drum clean-
       up process	 22

Table 3. Residual PCB levels in processed drums measured using the Dexsil L2000 PCB/chloride
       analyzer and EPA SW-846 Method 8082. .,	 23

Table 4- Field analytical results of quality control samples	 25

Table 5. Comparison of costs for a sampling program using the Dexsil PCB field method and EPA
       Method 8082	 29

                                      List of Boxes

Box 1: Process Optimization Decision Tree  •.	 8
Box 2: Process Evaluation Decision Tree	 8
Box 3: Production Phase Decision Tree	 12
Box 4: Hypothetical Random Sampling Protocol	 14
                                             VI

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                                                        EPA-542-R-99-003
                                                               May 1999
                Innovations in Site Characterization
Case Study: Dexsil L2000 PCB/Ch!oride Analyzer for Drum Surfaces
                     U.S. Environmental Protection Agency
                 Office of Solid Waste and Emergency Response
                        Technology Innovation Office
                          Washington, D.C. 20460

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                                          Notice

This material has been funded wholly by the United States Environmental Protection Agency under
Contract Number 68-W7-0051. Mention of trade names or commercial products does not constitute
endorsement or recommendation for use.

Copies of this report are available free of charge from the National Service Center for Environmental
Publications (NSCEP), PO Box 42419, Cincinnati, Ohio 45242-2419; telephone (800) 490-9198 or (513)
489-8190 (voice) or (513) 489-8695 (facsimile). Refer to document EPA-542-R-99-003, Innovations in
Site Characterization- Case Study: Dexsil L2000 PCB/Chloride Analyzer for Drum Surfaces. This
document can also be obtained through EPA's Clean Up Information (CLU-IN) System on the World
Wide Web at http://clu-in.org or by modem at (301) 589-8366. For assistance, call (301) 589-8368.

Comments or questions about this report may be directed to the United States Environmental Protection
Agency, Technology Innovation Office (5102G), 401 M Street, SW, Washington, D.C. 20460; telephone
(703) 603-9910.
                                              11

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                                 Dexsil L2000 PCB/Chloride Analyzer for Drum Surfaces

                                    Case Study Abstract	
                Dexsil L2000 PCB/Chloride Analyzer for Sampling Drum Surfaces
                      East Tennessee Technology Park, Oak Ridge, Tennessee
Project Name and Location:
East Tennessee Technology Park
Oak Ridge, Anderson County, TN
37831
Period of Project Operation:
1940 to current

Operable Unit:
Not applicable
Sampling and Analytical
Technologies:
1. Wipe sampling
2. Dexsil L2000PCB/Ghloride
Analyzer
CERCLIS #
Not applicable
                                    Current Project Activities:
                                    Environmental and waste management
                                    support for the Department of Energy
                                    including operation of an incinerator for
                                    wastes regulated by the Toxic Substances
                                    and Control Act (TSCA).
Point of Contact:
David M. Garden
U.S. Department of Energy
P.O. Box 2001
Oak Ridge, TN 37831 '
423-576-9262
cardendm@oro.doe.gov
Media and Contaminants:
Metal drum surfaces contaminated with
oily waste and soil residues from drum
contents which had consisted of
various polychlorinated bipheriyls
(PCB) waste materials.
Technology Demonstrator:
Department of Energy,
Oak Ridge Operations
Oak Ridge, TN 37831
 Number of samples analyzed during investigation:
 26 wipe samples (Note: The original intent of PCB analyses was to monitor the clean-up of 7,000 empty drums, requiring 400
 wipe samples. However, the clean-up work was aborted when the clean-up technology was found to be ineffective during the
 initial phase of the work during which 26 wipe samples were analyzed.)                  	••.
 Project Cost Savings:
 Analytical per sample costs (not including instrument cost or rental) for the Dexsil method is $12.50 compared to $50.00 for
 the GC/ECD laboratory method.  Had the project not been aborted, use of the analytical method would have resulted in more
 than $10,000 in analytical cost savings.                                   	•	^^
 Results:
 A field method for PCB analysis provided rapid feedback regarding the effectiveness of a process for removing PCB surficial
 contamination from empty drums. Rapid turnaround in field analyses resulted in the data user's ability to abort the clean-up
 work before expending additional resources on a drum clean-up process that was not working.
 Description:                                       •
 This case study describes how a field analytical method was used to measure PCB surficial contamination in empty drums that
 were cleaned by a new process. The Department of Energy (DOE) Oak Ridge Operations had obtained approval from the
 Environmental Protection Agency (EPA)-Region 4 to demonstrate the'cleanup of 7,000 empty TSCA-regulated drums using a
 new pelletized-GO2 scpuring technique. DOE proposed and EPA approved a sampling program to determine the effectiveness
 of the clean-up technology and evaluate compliance with EPA's regulatory'limits for releasing TSCA-regulated items. The
 proposed sampling program consisted of (1) statistical control limits for process monitoring, (2) random sampling of
 processed drums, (3) wipe sampling of container surfaces, and (4) rapid analysis of the wipe samples by a field method.
 During the trial -period, the clean-up technology vendor attempted to clean about 20 of the most highly contaminated drums.
 Field analyses of residual PCB contamination, which provided results within one hour of wipe sample collection, showed that
 the clean-up technology was not working as expected. On the basis of the field results, which were later'confirmed when the
 results of gas chromatography analyses became available, DOE aborted the drum clean-up project and the sampling program
 was terminated.                                                         	
                                                    Vll

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TECHNOLOGY QUICK REFERENCE SHEET
Case Study Name:    Dexsil L2000 PCB/Chloride Analyzer for Drum Surfaces
     T' >,"  -.'^'jl., *• _!/*'vr?'^  i-'jf't- --s^"1"11 '/-- ^-^
  Summar§ of-Cas^ Study's PerforraafieljEnfpnnaitioa , Jr'
  Project Role:
  Used to measure residual surface PCB
  contamination in drums cleaned by a
  new process.
   Cost/Performance Information:
   Analytical per sample cost (not including instrument cost or rental) for the Dexsil method is $12.50 per
   sample compared to ~$50.00 for the GC/ECD laboratory method.  If the drum cleaning project proceeded
   as planned, use of the analytical method to verify regulatory compliance would have resulted in more than
   $10,000 in analytical cost savings.
  Total Cost: Information not available
                                                       Project Cost Breakdown
  Instrument Cost:
  $3500
Consumables Cost:
Test kit reagents, $12.50 per
sample
Labor Cost:
Information not available
Waste Disposal Costr Information
not available
  Site-Specific Performance Observed:
  Blanks analysis results ranged from 0.6 to 3.1 ug/100 cm2. Recoveries on Arochlor 1260 10 ug/100 cm2 standards (reported as Arochlor 1242) were
  greater than 100% (range: 118-263%). Although the Dexsil field results were qualitatively consistent with the lab verification analyses, the latter
  values tended to be higher than corresponding field measurements. Oily residues on the wipe samples may have exacerbated differences in extraction
  efficiencies between the field and laboratory methods, each of which used different solvents and extraction times.  •	


   Vendor Contact:
   John Siliman
   Technical Support
Vendor Information:
Dexsil Corporation
One Hamden Park Drive
Hamden,CT 06517
203-288-3509
    Limitations on Performance:
    Cannot distinguish PCB congeners; identification of Aroclor not possible.
   Availability/Rates:
   Instrument and test kits (reagents
   + extraction vessels) can be
   purchased from Dexsil
 Principle of Operation: Metallic sodium strips PCB molecules of
 chlorine; chloride levels are measured by a chloride-ion-specific
 electrode and converted to PCB concentration using known chlorine
 percentages present in Aroclors.
                                     Power Requirements!
                                     120V
   Generjjl petfoMagici Infoieakfidn1'';

   Rate of Throughput: 5 samples per hour when sample preparation and
   analyses were done outdoors; 10 samples per hour when' sample
   preparation and analyses were done indoors (from ETV study)
                                Known or Potential Interferences:
                                Other chlorinated organics that are preferentially soluble in a non-polar
                                solvent; iodine and bromine
   Applicable Media/Matrices:
   Soil, surface wipes, dielectric
   fluids and oils
   Wastes Generated Requiring
   Special Disposal: All materials
   and reagents that contact PCB-
   contaminated material may be
   considered TSCA waste;
   applicable regulations for TSCA
   waste disposal should be checked
   before disposal of used materials
 Analytes Measurable with Commonly
 Achieved Detection Limit Ranges:
 PCBs, 2 ppm or 2 ug/100cm2 (if a 1000
 cm2 area is wipe sampled).
          Other General Accuracy/Precision Information:
          (from ETV report EPA/600/R-98/109; see website
          www.epa.gov/etv/library.htmftverifications)

          Average recovery in soil samples: 208%
          Average recovery in extract samples: 149%

          Precision in soil samples as relative standard deviation (RSD): 23%
          Precision in simulated extract samples as RSD: 14%
                                                                  IX

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                              Dexsii L2000 PCB/Chloride Analyzer for Drum Surfaces

BBBEXECUTIYE
This case study describes a field analytical method that was used to measure PCB surficial contamination
in empty drums to be cleaned by a new process. Approximately 7,000 empty 55-gallon drums that previously
contained PCB-contaminated material had accumulated at the Department of Energy (DOE) ' s East Tennessee
Technology Park in Oak Ridge, TN. Because disposal of these drums following regulator-approved methods
would have been very costly, DOE requested permission from the Environmental Protection Agency (EPA)-
Region 4 to demonstrate the  cleanup of these drums using a new CO2 scouring technology. DOE also
proposed and EPA approved a sampling program to demonstrate the effectiveness of the clean-up technology
and evaluate compliance with EPA' s regulatory limits for releasing PCB-contaminated items . The proposed
sampling program consisted of (1) statistical control limits for process monitoring, (2) random sampling of
processed drums, (3) wipe sampling of container surfaces, and (4) rapid analysis of the wipe samples by a
field method.

While taking advantage of the cost effectiveness and quick turnaround of field methods, DOE minimized the
risk of violating regulatory limits by selecting the field method based on the following criteria: (1) if field
results are biased, they must be biased high, (2) the field technique should provide a low probability of false
negative results, (3) the detection limit should be well below the lowest action/decision level, and (4) the
field technique should provide quantitative results rather than results in the form of ranges or intervals. Of
the six field methods evaluated during the Environmental Technology Verification (ETV) project co-
sponsored by EPA and DOE, only the Dexsii L2000 PCB/Chloride Analyzer satisfied these criteria and was
thus selected for monitoring the drum cleaning process.

During the initial phase of the project, the CO2 scouring technology vendor attempted to clean 20 of the most
highly contaminated drums. The Dexsii PCB Analyzer was used to monitor residual PCB contamination in
the processed drums during this trial period.  Field analyses, completed and reported within one hour of
sample collection, showed that the clean-up technology was not working as expected.  On the basis of the
field-generated results, which were confirmed by  wipe samples  sent to an  off-site laboratory  for gas
chrpmatography analysis, DOE decided to abort the drum clean-up project before additional resources were
expended.  Although only a limited data set was obtained to evaluate the overall performance of the Dexsii
field method, this case study demonstrates the usefulness of field methods for rapid decision-making.

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Dexsil L2000 PCB/Chloride Analyzer for Drum Surfaces
i PROJECT INFORMATION!

Identifying Information
Demonstration Project for.Pelletized CO2 Drum Cleaning Process
East Tennessee Technology Park
Oak Ridge, Anderson County, TN 37831

Background [1,2] .

Project Use: The East Tennessee Technology Park.(ETTP), formerly the K-25 project, was built
in the 1940s as the Oak Ridge Gaseous Diffusion Plant, a facility where highly enriched uranium
was produced for the U.S. Army's Manhattan Project. Since then, facility ownership has been
transferred to the U.S. Department of Energy (DOE), and its mission has evolved to support
environmental management activities within DOE's Oak Ridge Operations (ORO). Specific
activities currently being conducfe^lTETTFinclTMeThe
Act (TSCA) incinerator, which receives TSCA-regulated waste for disposal from DOE facilities,
and technical support for waste management within the DOE/ORO complex. ETTP is currently
managed by Bechtel Jacobs Company, LLC for DOE.

Release Investigation/History: As of early 1998, approximately 7,000 empty drums that
previously contained.materials contaminated with polychlorinated biphenyls (PCBs) were stored
at ETTP. At one time the drums contained TSCA-regulated waste generated within the DOE
complex that were either repackaged or disposed of in the ETTP's TSCA incinerator." Drum
contents ranged from transformer oils to contaminated soils with PCB levels exceeding 50 ppm.
Records regarding the contaminant characteristics of the previous contents exist for most of these
drums, however residual PCB surficial contamination in these drums had not yet been
characterized.

Regulatory Context: Under TSCA rules, the handling and disposal of empty drums that
previously contained PCB-contaminated material depends on the level of PCBs that were in the
drums. If the contents exceed 500 ppm of PCBs, the empty drum must be disposed of in ah
incinerator that complies with 40 CFR 761.70, or in a chemical waste landfill that complies with
40 CFR 761.75. Alternatively, the drum can be triple-rinsed according to the standard
procedures in 40 CFR 761.79.

Some of the 7,000 empty drums at ETTP contained wastes that exceeded 500 ppm. Because
disposal of these drums in an incinerator or chemical waste landfill would be very costly, and
decontamination by triple-rinsing would generate a large volume of TSCA waste [2], DOE
requested approval from EPA Region 4 to demonstrate an innovative scouring technology by
which pelletized CO2 is utilized to remove surficial contamination from the drums. Pursuant to
the Oak Ridge Reservation PCB Federal Facility Compliance Agreement (FFCA) between EPA
and DOE, containers cleaned using a process other than triple-rinsing must be tested for residual
PCB contamination before disposal. PCB surface levels must not exceed 10 ng/100 cm2 if the
cleaned drum is to be free-released, or 100 ug/100 cm2'if the drum is to undergo metal recycling.

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Dexsil L2000 PCB/Chloride Analyzer for Drum Surfaces
i PROJECT INFORMATION, CONT'D.M
Vendor claims regarding the CO2 scouring technology led DOE to believe that drums cleaned by
this process would show residual PCB levels acceptable for free-release. Furthermore, the waste
generated by this clean-up technology and the overall clean-up cost per drum would be an order
of magnitude less than that associated with triple-rinsing.

Because the pelletized CO2 clean-up process was not an EPA-approved technique, DOE
proposed implementing a testing program to ensure that EPA's established surface cleanup
standards would be met. The testing program was designed to include (1) statistical control
limits for process monitoring, (2) statistical random sampling of processed drums, (3) wipe
sampling of container surfaces, -and (4) rapid analysis of the wipe samples by an on-site
measurement method. Through a memorandum issued to DOE [2], EPA Region 4 approved the
demonstration of the CO2 cleaning technology, and concurred with the testing program DOE had
proposed with minor modifications. Within the context of the Oak Ridge Reservation PCB
Federal Facility Compliance Agreement, flexibility is accorded to the Region in applying PCB
regulations to DOE's particular problems with managing PCB/radioactive waste streams.

Project Logistics/Contacts '
Federal Lead Agency: U.S. Department of
Energy, Oak Ridge Operations

Federal Oversight Agency: Environmental
Protection Agency, Region 4

DOE Program Manager:
David M. Garden
U.S. Department of Energy
P.O. Box 2001
Oak-Ridge, TN 37831
423-576-9262
cardendm@doe.oro.gov

Project Engineer:
Steve E. Foster
Bechtel Jacobs Company, LLC
P.O. Box 4699 MS7234
Oak Ridge, TN 37831-7234
423-574-8032
fosterse@bechteljacobs.org
Technical Consultant for DOE:
Chip Davis
SMS Lac.
55 Jefferson Circle
Oak Ridge, TN 37830
423-576-0250

Analytical Chemist:
N. Katy Huffaker
Bechtel Jacobs Company LLC
P.O. Box 4699 MS7169
Oak Ridge, TN 37831-7169
423-576-9186
huffakernk@bechteljacobs.org

Regulatory Agency Contact:
Craig Brown
U.S. Environmental Protection Agency;
Region 4
Atlanta Federal Center
61 Forsyth Street, SW
Atlanta, GA 30303-8909
404-562-8990
4

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Dexsil L2000 PCB/Chloride Analyzer for Drum Surfaces

(MEDIA AND PONTAMTMA VTSH—B^MMP^^

Matrix Identification

Type of matrix sampled and analyzed: Drum surfaces of 55-gallon drums

Project Geology/Stratigraphy

This information is not relevant to this project.

Contaminant Characterization ; '

Primary contaminant groups: Polychlorinated biphenyls (PCBs)

Matrix Characteristics Affecting Characterization Cost or Performance

PCB surface contamination in the processed drums was characterized by wipe sampling using
gauze pads saturated by a solvent (see detailed description under Characterization Technologies).
The presumption is that all the PCB contaminants on the sampled surface are effectively
collected by the gauze pad. However, if a significant oily residue is present, the gauze pad can
become saturated and cannot absorb all the oil present on the sampled surface. Under such
conditions, the measured surface contamination can be negatively biased. These effects would
apply for both the field and laboratory analyses of the wipe samples. According to personnel
involved with the project, oily residues were observed in some of the drums even after they had
been processed. Thus, the analytical results for the highly contaminated drums may
underestimate the actual levels of residual surface contamination.

Oily residue on the wipe samples could also exacerbate differences in extraction efficiency
between the field and laboratory methods. This is discussed in more detail under the Section on
Performance Evaluation.
[PROJECT CHARACTERIZATION PROCESS j
Goal of Characterization
DOE obtained approval from EPA to demonstrate an innovative CO2 scouring technology to
remove surficial contamination from 7,000 empty TSCA drums that were in storage at ETTP.
Because this new technology had not been approved by EPA as a substitute for the standard
triple-rinsing procedure outlined in 40 CFR 761.79, monitoring of the clean-up process was
required to certify its effectiveness. DOE and EPA agreed on a sampling and analysis plan [2]
which would establish with a known level of confidence that the clean-up process was meeting
regulatory goals, i.e., that residual PCB surface levels were below 10 fig/100 cm2 if the cleaned
drums were to be free-released, or below 100 ug/100 cm2 if the cleaned drums were to be
subjected to metal smelting. Using the Data Quality Objectives Process to organize the goals and
expectations of this project produces the following outputs:

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Dexsil L2000 PCB/Chloride Analyzer for Drum Surfaces
[PROJECT CHARACTERIZATION PROCESS CONT'DJ
1. State the Problem: This problem can be stated in two parts:
• Demonstrate a cheaper, effective drum cleanup method.
• Use a cheaper, rapid turn-around analytical method to sample and analyze a
representative number of the drums to ensure cleanup goals are met.

2. State the Project Decision(s):
• Determine whether the new cleaning process can achieve one of two preferred drum
disposal options by meeting applicable regulatory levels: free-release (10 |j.g/100 cm2)
and/or metal recycling (100 jag/100 cm2).
• Designate each 500-drum batch as appropriate for one or the other disposal, option.

3. Define the appropriate data inputs:
• PCB concentrations (as ug/100 cm2) in any residues remaining on the inside surfaces of
drums after cleaning.

4. Define the conditions under which to collect data and other study boundaries:
• Wipe samples will be taken from the drum's inside surfaces, and analyzed by a method
which can provide the requked PCB data.
• The number of drums from each 500-drum batch that will be sampled will be determined
according to a statistically-designed sampling plan.
• The collection and analysis of samples will use a field analytical method with a
defensible quality assurance plan.

5. State the Decision Rule(s):
• Decision Rule for using the new cleaning process: If the process is unable to clean drums
to either the free-release or metal recycling regulatory criteria, then the new process
cannot be used.
• Decision Rule for the free-release disposal option: If the nominal action level of 10
jig/100 cm2 of total PCBs cannot be achieved, the free-release option cannot be used to
dispose of drums.
• Decision Rule for the metal recycling disposal option: If the nominal action level of 100
jig/100 cm2 cannot be achieved, the metal recycling option cannot be used to dispose of
drums.

6. Specify limits on decision errors: For each batch of 500 drums, under a worst case-scenario,
there must be 95% confidence that no more than 10% of the drums in the batch exceed the
nominal action level and a 95% confidence that no more than 10% false negative analytical
results are produced by the analytical method. It was expected that, with the safety factors built
into the statistical and analytical design, actual exceedances would be much less. After
generation of the statistical data for each batch of drums, the actual probability of exceeding the
nominal action level will be determined from the analytical data sets, and the statistical
confidence actually achieved will be documented in the project report.

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                       Dexsil L2000 PCB/Chlbride Analyzer for Drum Surfaces
I PROJECT CHARACTERIZATION PROCESS CQNT'Djg	•	i	•

 [The reader is cautioned that depending on the regulatory context, the use of a sampling and
 analysis plan that permits any statistical exceedance ofTSCA regulatory limits for PCBs might
 not be acceptable to the regulating entity. Under the Oak Ridge Reservation PCB Federal
 Facility Compliance Agreement, flexibility in setting statistical limits on decision errors was
 permitted by Region 4 for this project evaluating an innovative drum cleanup method.]

 7. Optimize the Design:
 •      Optimization of the sampling and analysis plan will be carried out according to detailed
        quality control and corrective action measures. With the exception of the use of
        periodic field duplicates as described in the analytical QA/QC plan; a single sample will
        be taken to characterize each drum, as long as the following assumption is demonstrated
        to be valid: Any PCBs remaining after drum cleaning are uniformly distributed on the
        inner surfaces of the drums.

 Since it was discovered during the initial evaluation of the cleaning process that it could not
 achieve even the 100 |ig/100cm2 regulatory limit, it could be said the project was "optimized" by
 aborting it so that no more resources than necessary were expended on an unworkable project.

 The analytical Data Quality Objective (DQO) Summary Statement for this project is "Verify with
 at least 95% confidence that no more that 10% of 7,000 drums remain contaminated at applicable
 regulatory levels after being cleaned with the new process."

 Sampling Workplan	   .	^^_^^_

 Monitoring of the drum clean-up process was divided into an initial intensive sampling phase for
 process optimization followed by a production sampling phase for process control and
 effectiveness verification. A discussion of each sampling phase is provided below, and follows
 the decision tree graphics presented  in Boxes 1 and 2, below.

 Process Optimization: Initial Intensive Sampling (See Box  1)

 The objectives of this phase were (1) to determine whether the CO2 process can achieve at least
  one of the regulatory goals (100 ug/100 cm2 for metal recycling, or 10 ng/100 cm2 for free
 release), and (2) to obtain process control information that will be used to monitor the clean-up
 process during the subsequent production phase.

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Dexsil L2000 PCB/Chloride Analyzer for Drum Surfaces
{PROJECT CHARACTERIZATION PROCESS CONT'D.!
Clean a 25-drum Batch
Optimize Cleaning
Procedure
Legend

S0 a Dexsil Sample Results In ugflOOcnr?
St a Laboratory Sample Results In ug/100cnf
Test All Drums ,
Dexsil and
EPA Method 8082
Move, to
Process Evaluation Phase
s this the secon
round of
processing?
Box 1: Process Optimization Decision Tree
Clean a 50-drum Batch
Reoptimlze Process
No

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DexsU L2000 PCB/Chloride Analyzer for Drum Surfaces
i PROJECT CHARACTERIZATION PROCESS CONT'D.KSSSoSi

For this initial phase, 75 of the most contaminated drums were selected based on visual
inspection and records of prior contents. The clean-up technology vendor was permitted to
process 25 of the 75 drums in order to determine the optimum amount of CO2 scouring time
needed to remove surficial contamination to acceptable levels (see Box 1). Residual
contamination during this optimization stage was measured by taking wipe samples from the
inner surfaces of the processed drums, and analyzing the wipes using the Dexsil PCB test kit.
Duplicate samplings of 10 drums were sent to the laboratory for confirmatory analysis by gas
chromatography. Wipe sampling and the Dexsil PCB test kit are described in more detail in the
Characterization Technologies section, below.

Unfortunately, it quickly became clear that neither regulatory goal could be achieved. The
demonstration was discontinued because the process was deemed "ineffective" before the next
step of the process optimization and evaluation plan was reached. For the educational purposes
of this case study, however, further discussion of the project plan will continue in order to
explain the rationale of this study.

After optimization, the vendor was to process the remaining 50 drums using the optimized
conditions to demonstrate process effectiveness to DOE and EPA (see Box 2). The surfaces of
those 50 processed drums would then be wiped, and the sample results used to determine
whether or not the process can achieve the regulatory goal of 10 p.g/100 cm2 for free-release of
the drums, or 100 jag/100 cm2 for metal smelting of the drums. The decision rules are as
follows:

Acceptance Criteria for Process Effectiveness

(1) If the residual surficial contamination as measured by the Dexsil PCB test is less than 5
ug/100 cm2 for all 50 drums, then the process is deemed "fully effective for free
release." There is an additional requirement in the workplan that "the upper 95%
confidence level on the mean of the 50 consecutively processed drums must be less than
the regulatory cleaning goals." Depending on the variability present in the 50 sample
results, it is possible to have an upper 95% confidence level that is greater than the
regulatory cleaning goal, even though each of the 50 samples is less than the regulatory
cleaning goal. If the mean of the data were significantly less than the regulatory cleaning
goal, then this outcome might not occur. But if the mean of the data is close to the
regulatory goal with enough (expected) variability in the data, there is a good chance that
the upper 95% confidence level would exceed the regulatory limit.

(2) If one or more drums has residual levels above 5 ug/100 cm2 as determined by the field
test, those drums will be re-sampled and the wipes will be sent to a fixed laboratory for
analysis by EPA Method 8082 (Polychlorinated Biphenyls (PCBs) by Capillary Column
Gas Chromatography) [8]. If the fixed lab analysis results are less than 10 ug/100 cm2
for all samples, then the re-sampled drums are considered acceptable and the process
deemed "fully effective for free release." If the fixed lab analysis results are greater than
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Dexsil L2000 PCB/Chloride Analyzer for Drum Surfaces
i PROJECT CHARACTERIZATION PROCESS CONT'D.HBHn^^B

10 jig/100 cm2 but less than 100 |ig/100 cm2 for all samples, then the process is deemed
"fully effective for metal recycling." If at least one of the fixed lab results is greater than
100 fig/100 cm2, then the process is deemed "ineffective" and the clean-up vendor may
be asked to re-optimize the process and demonstrate technology effectiveness using
another set of 50 drums.

The original project design was directed at meeting the free release regulatory standard
of 10 ug/10p cm2. 'However, if the cleanup process was unable to meet that stringent
standard, the same design, with minimal modifications, could be used to meet the
standard for metal recycling of 100 |ig/100 cm2. For example, 50 and 100 p.g/100 cm2
could replace 5 and 10 jig/100 cm2 as the field-specific and nominal regulatory action
levels, respectively.

The decision trees above (Boxes 1 and 2) establish the role and usefulness of the Dexsil kit as a
screening tool to select samples that require testing by Method 8082 to confirm regulatory
compliance during these initial phases of work which were designed to establish process
effectiveness. If the cleaning contractor had been able to satisfy the "full process effectiveness"
criteria for at least one of the two goals and had successfully processed a batch of 50 drums
according to the decision tree above, the mean and standard deviation (SD) of residual surface
contamination in these 50 drums, as determined by results of the Dexsil PCB test kit, would be
used as parameters for process control during the production phase. This is accomplished by the
development of a control chart. An example of a control chart is provided in Figure 1 using a
fictitious data set that might have resembled the data generated during the 50-drum process-
effectiveness evaluation, had the cleaning process proven "fully effective for free release."
Figure 2 shows a control chart that may have been created had the cleaning technology failed the
free-release goal, but was demonstrated "fully effective for metal recycling." The Mean, Process
Warning Limit, and Process Control Limit for a control chart would be derived from the data
generated during the 50-drum Process Evaluation Procedure, during which the cleaning process
would be maximally optimized. Later, during the production phase of work, data collected from
each of 28 randomly selected drums from each 500-drum batch would be plotted on the chart as a
means of assessing whether the cleaning process continued to perform optimally as all 7,000
drums were cleaned (described in more detail below).
10
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Dexsil L2000 PCB/Chloride Analyzer for Drum Surfaces
OJECT CHARACTERIZATION PROCESS CON1 'D.BHHBl^^BBB
Batch No: Name:
7n
.0 -
CM
V- e n
£ 5.0 -
U
§
B»4.0 -
•3
3.0 -
2.0

: Process Control Limit + 3SD I
Date:

; Process Warning Limit + 2SD

:
: Mean |
;

V 3 ' 5 ' 7 ' 9 '- 11 ' 1'3 ' 1'B ' 17 ' 19 21 ' 23 ' 25 ' 27 '
2 46 8 10 12 14 16 18 20 22 24 26 28
Order of Random Drum Samples

Figure 1: Process Control Chart for Free Release

(Batch No: . 1 Name:
58 -f

Aft „ „

43 --
*** 1Q
e -30 - -
^J| sjsj
o
i,28::
23 --
18 -•

Date:

Process Conirol Limit +3SD

Process Warning LimH + 2SD

Mean

t > i t < t > > • --..t 1 • L.

3 i ' 3' ' 5 7 ' 9 ' 11 ' 13 ' 15 ' 17 ' 19 ' 21 ' 23 ' 25 ' 27 '
2 4 6 8 ' 10 12 14 16 18 20 22 24 26 28
Order of Random Drum Samples

Figure 2: Process Control Chart for Metal Recycling
11
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DexsU L2000 PCB/Chloride Analyzer for Drum Surfaces
i PROJECT CHARACTERIZATION PROCESS CONT'D.SSSSSS

Process Verification and Control: Production Phase Sampling

Had the process been deemed "fully effective" either for free release or metal recycling!
production phase sampling would be conducted with random verification sampling to ensure that
the process remains in control and that process action limits, established during the Process
Evaluation Procedure and used to prepare the Process Control Chart, are not exceeded (see Box
3).
Process Not Effective
Batch Compliant for
Metal Recycling
i

Plot Dexsll Data on
Control Chart: Metal
Recycling
Process within Control Limits
Legend

SD = Dexsll Sample Results In ug/IOOcm !
3 Laboratory Sample Results In ug/IOOcm1
Box 3: Production Phase Decision Tree
12
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Dexsil L2000 PCB/Chloride Analyzer for Drum Surfaces
I PROJECT CHARACTERIZATION PROCESS CONT'D.SS^SSBS

The drams will be processed in batches of 500, and 28 drams per batch will be randomly .
selected for wipe sampling and analysis using Dexsil PCB test kits, and the results plotted on a
Control Chart (28 sample results plotted on each chart, with one chart plotted per batch of 500
drams).

A discussion of two easily implemented protocols for random sampling of these drams appears
in Box 4. The number of samples per batch was determined based on the statistical design
proposed for this project, which was a nonparametric one-sided tolerance limit that does not
require a presumption about the normality of the distribution of the measurements [4]. Using a
sample size of 28 randomly selected drams allows one to state with 95% confidence that no more
than 10% of a 500-dram batch will have residual levels greater than the highest result in the set
of 28 random samples. Stated another way, the statistical design assures, that there is less than a
5% chance that more than 50 drams out of a 500-dram batch will have a surficial PCB
concentration greater than the highest result within the set of 28 randomly selected samples. It is
possible with this statistical test to select more stringent tolerance limits, for example, instead of
using the criteria that no more than 10% of a 500-dram batch would have residual levels greater
than the highest result at the 95% confidence level, it is possible to specify that only 1% of a 500-
dram batch (or only 5 drams) would have levels greater than the highest result at the 95%
confidence level. Choosing this tolerance limit would raise the required number of randomly
selected drams to be sampled to about 298, rather than 28, substantially increasing the cost and
effort involved. Because of all the other conservatively stringent controls in place for this
sampling plan, EPA Region 4 was comfortable permitting a less rigorous confidence level for
this aspect of the sampling design. The reader should also recall from previous discussions that
this type of statistical sampling design may not be acceptable to regulators under other PCB
cleanup or decontamination scenarios.

Note that the data from the 28 randomly sampled drams from each 500-dram batch serve at least
two, and possibly three, distinct purposes:

1) Use of the data (specifically, using the highest result of the 28-sample data set) in determining
compliance with the nonparametric one-sided tolerance limit statistic used to predict residual
levels of PCBs in the 500-dram batch after cleaning [4] and ensure meeting the defined Decision
Error Limit (see the Acceptance Criteria for Processed Drams, p. 13);

2) Plotting the 28 data points on control charts to permit close monitoring of the efficiency of the
cleaning process so that re-optimization of the CO2 scouring process can be performed at the
first indication of a loss of efficiency (see Process Control, below); and

3) The possible use of the data to calculate parametric or nonparametric statistical parameters, as
appropriate (such as a confidence limit on the 99th percentile for a "not-to-exceed" regulatory
standard) [8].

The decision tree in Box 3 assumes that the initial testing had demonstrated that the process
13
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Dexsil L2000 PCB/Chloride Analyzer for Drum Surfaces
i PROJECT CHARACTERIZATION PROCESS CONT'D.1
Box 4: Hypothetical Random Sampling Protocol
The statistical procedure for selecting the number of drums that would be sampled in each batch for the one-sided non-parametric
tolerance limit is as follows: [7]

n = log(alpha)/log(P) = log(0.05)/log(.90)
n = -1.3010/-0.045a = 28'
Where:
alpha = 1 - level of confidence desired; and
P = the percent of compliant drums.

A 500-drum batch is assembled (from the total of about 7,000 drums) in an area hi preparation for the cleaning process. A
random number generator is used to select 28 numbers between 1 and 500. ORor example, say that 34 and 79 are two of the
random numbers selected.) Before any drums are cleaned, the selected 28 random numbers are ordered on a list, from lowest to
highest in numerical order. Then the cleaning process is begun. As each dram is about to be subjected to the cleaning process, it
is assigned the next consecutive number (from 1 to 500). When the 34th drum is cleaned, it is immediately sampled before being
stacked with the rest of the cleaned drums. When the 79th is cleaned, it is sampled before being stacked, and so on.

For example:
Order of Sampling
Order of Drum
Cleaning & Drum ID
Number
1
34

2
79

3
101

'4
128

5
188

...

25
305

26
420

27
452

28
463

Alternatively, all 500 drums could be numbered as they are assembled in preparation for cleaning. After all have been assigned
numbers, use a random number generator to select the numbers of the 28 drums to be sampled, and record those numbers in the
order in which they were chosen. Cleaning does not have to proceed in any particular order. When a drum is cleaned which was
previously selected for the set of 28, it is sampled before being stacked with the rest of the cleaned drums. The order of cleaning
of these numbered drums must be preserved, but the numbers themselves do not have to be in order.

For example:
Order of Sampling
(after cleaning)
Drum ID Number
1
305
2
251
3
301
4
34
5
101
...

25
452
26
292
27
197
28
79
Both of these approaches permit two desirable outcomes:
1) Randomly selected drums do not have to be retrieved from piles of stacked drums to be sampled.
2) One of the statistical process controls on the cleaning procedure is to track whether the cleaning process is trending out of
control by plotting sample results on a control chart. If the order of cleaning is preserved in the order of plotting on the control
chart, such a trend can be detected. If the order of cleaning is not preserved on the control chart, trend information will be lost.
could achieve the regulatory limit for free release, but routing batches of drums to the metal
recycling option is possible if some batches did not meet the criteria for free-release, but did
meet the less stringent recycling criteria.
14
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Dexsi! L2000 PCB/Chloride Analyzer for Drum Surfaces
I PROJECT CHARACTERIZATION PROCESS

Acceptance Criteria for Processed Drums

(1) If all 28 randomly-selected drums have residual contamination less than 5 ug/100 cm2
using the Dexsil test kits, the batch of 500 drums are deemed clean enough for free
release. Since the nonparametric statistical procedure used ensures that no more than
10% of the 500 drums in a batch would exceed the highest result in the data set, and
since the highest result is less than 5 ug/100 cm2, such a data set meets the defined
statistical goal given in Step 6 of the DQO Process that no more than 10% of the batch
exceed the regulatory limit of 10 ug/100 cm2

(2) If one or more of the 28 drums has residual contamination greater than 5 ug/100 cm2
using the Dexsil test kits, these drums will be re-sampled and the wipes analyzed using
EPA Method 8082. If all of the fixed lab analysis results are less than 10 ug/100 cm2,
then the 500 drums are deemed clean enough for free release. If at least one of the fixed
lab analysis results is greater than 10 ug/100 cm2 but less than 100 ug/100 cm2, then the
500 drums are deemed acceptable for metal recycling. If at least one of the fixed lab
analysis results is greater than 100 ug/100 cm2, then the drums are deemed unacceptable
for free release or recycling and the vendor may be required to re-process all 500 drums
until random sampling demonstrates that one of the regulatory limits has been achieved.

Process Control

After the data from the 28. random samples are evaluated using the applicable decision tree, and
the corresponding 500-drum batch is deemed "clean," the data from the 28 random samples will
be used to indicate whether process effectiveness is beginning to degrade. This is done by
plotting the data on a control chart. Each batch of 500 drums would have its 28 samples plotted
on a copy of the control chart generated during Process Evaluation, and the cleaning order must
be preserved when plotting the data on the chart. Deterioration of cleaning effectiveness would
be apparent if the results of any of the 28 random samples began to rise above the limits
established on control charts during process optimization. Even if those results were not yet
exceeding the regulatory limit, it would be a signal that the cleaning process might again need to
be optimized, and early corrective action could be implemented. The following criteria would
have been used as indicators of diminishing process effectiveness.

1. Three or more of the 28 samples exceeds x + 2 SD (i.e., the Process Warning Limit),
where x and SD are the mean and standard deviation respectively of the residual levels
in the 50 drums used to initially demonstrate "full effectiveness" and prepare control
charts.

2. At least one of the 28 samples exceeds X + 3 SD (i.e., the Process Control Limit).

3. If any seven consecutive data points have residual levels greater than X.
15
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Dexsil L2000 PCB/Chioride Analyzer for Drum Surfaces
(PROJECT CHARACTERIZATION PROCESS CONT'D.J^^SSSSS

On-Going Process Control Validation

The random sampling scheme used for process verification does not guarantee that none of the
500 drums will exceed the regulatory limits. However, the sampling scheme does ensure with a
95% confidence level that the maximum number of drums that can violate the regulatory limit in
a batch of 500 drums is 50, under a worst case scenario. It is possible that data from the 28
random samples in a batch might be used to project the probability that an individual drum
within that batch would exceed a regulatory limit. As-the project proceeds, the data from each
round of 28 random samples is added to the data collected during previous rounds. The. mean and
standard deviations of these data are calculated, and the results compared with the process
control limits for the project. If the comparison shows a significant difference between the
calculated mean or standard deviations and the process control assumptions, this will serve as a
warning that the early assumptions about the variability of the concentrations in the drums to be
cleaned may not be valid.
16
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Dexsil L2000 PCB/Chloride Analyzer for Drum Surfaces
i CHARACTERIZATION TECHNOLOGIES ™HHimuii-^«™~-~»«—mimim

Wipe Sampling •

Residual PCB contamination in the processed drums is tested by wipe sampling, a standard EPA
technique for sampling contamination on smooth surfaces. [5]. Wipe sampling is accomplished
by applying 2 mL of chromatographic-grade hexane to a sterile gauze pad, then using the soaked
gauze pad .to wipe a pre-determined, pre-measured area (1000'cm2 or 12.5-in x 12.5-in) on the
surface, of a drum. Pre-measured aliquots of hexane were provided by Dexsil in sealed glass
ampules to prevent contamination from external sources prior to use. After sampling, the hexane
was allowed to evaporate, and the wipe was then extracted and analyzed following procedures
for the Dexsil PCB test method (see below).

As noted in the section on quality control measures below, a significant component of
measurement variability in wipe samples can be from heterogeneous analyte distribution of the
surface being sampled. This must be considered when establishing QC criteria for replicate
measurements and comparisons between different analytical methods (e.g.,'field vs lab) using
separately collected wipe samples. .

As discussed elsewhere in this case study, a number of factors can complicate wipe sampling
(such as the amount and character of the sampled residue) and compromise analytical integrity.
If complicating factors are anticipated during project planning, modifications to the wipe
sampling procedure can be evaluated to ensure the representativeness and comparability of the
analytical testing.

PCB Analysis Using the Dexsil L2000 PCB/Chloride Analyzer

The Dexsil L2000 PCB/Chloride Analyzer is a field-portable instrument designed to quantify
PCB concentration in soils, dielectric fluids, and surface wipes. For wipe samples, PCBs are
extracted from the wiped sample by solvating the wipe with 10 mL of isooctane for 30 seconds.
Inorganic chloride and water are removed from the isooctane extract by passing it through a
Florisil cartridge, then the extract is mixed with a reaction solution and metallic sodium (which
dechlorinates the PCB molecules). The free chloride released into the reaction solution is
measured with an ion-specific electrode. Only chloride which was part of any organic molecule
contributes to the signal (the Dexsil PCB kit is not specific for PCBs); inorganic chloride
originally present in the sample does not interfere. The output of the chloride-specific electrode
is electronically converted to the surficial PCB contamination (in jig/100 cm2) of a 1000 cm2
wipe sample area. The free chloride concentration is converted to a Arochlor concentration
based on the analyst's choice of one of four different settings—Aroclor 1242, Aroclor 1260,
Askarel A (60% Aroclor 1260/40% trichlorobenzene), and total chloride. The instrument does
not report Aroclor 1254. Aroclor identification can not be made because the measurement
technique can not distinguish among the PCB congeners. Hence, the user needs to use site
history or previous data to set the analyzer to convert the chloride concentration to the
appropriate PCB congener. Alternatively, the user can set the analyzer to report results as
Aroclor 1242, which has the lowest percentage of chlorine, to obtain the most conservative
(highest) PCB sample concentrations.
17
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Dexsil L2000 PCB/Chloride Analyzer for Drum Surfaces
i CHARACTERIZATION TECHNOLOGIES, CONT'D.i
Quality Assurance/Quality Control Measures ,

The key to an effective QA/QC plan is that it take into consideration the limitations and strengths
of the sampling and analytical methods involved, and the goals of the project. To meet the goals
set forth in the preceding section, the Dexsil kit must be shown to produce data which meet the
needs of site-specific decision process. One of the most important needs is that the site-specific
results are consistently comparable (or consistently and predictably conservative) as compared to
the 'reference methods' by which the TSCA action levels were derived. Had the drum cleaning
method worked, that is, had the pelletized CO2 process been able to physically remove the oily,
often viscous, residue coating the inside surfaces of many of the drums, demonstrating
comparability between the wipe sample results obtained by the Dexsil kit and those obtained by a
traditional laboratory may have been a simple matter.

Unfortunately, since the cleaning process was ineffective at removing the oily residue, wipe
sampling and analysis became a difficult task for a number of reasons which are discussed in
more detail later in this section. If good comparability between laboratory and field
measurements at all analyte concentrations is to expected to provide data defensibility,
representative sampling and analysis issues must be addressed, or this aspect of the quality
assurance plan will fail.

Since it was not expected that the drum cleanup method would leave so much oily material, the
sampling and analytical difficulties encountered were not anticipated. Compliance with all
aspects of the QA/QC plan (as it was designed) could not be demonstrated in the limited data set
generated. However, since the first goal of the project was to establish whether or not the
innovative drum cleanup method could work, and since both the physical and analytical evidence
was overwhelming that it did not, compliance with the QA/QC plan was not relevant to the
decision to abort the pelletized CO2 demonstration project due to a lack of effectiveness.

A defensible QA plan requires refinement of analytical and sampling procedures to cope with
matrix issues if the data are to be expected to support complex decision-making. This is best
done by a pilot study which establishes the optimum sample selection, collection, extraction,
cleanup, analysis and interpretation procedures to address site-specific conditions and decision
goals. It should be kept in mind that some studies have found variability due to sampling factors
to routinely be 3 or more tunes as large as variability stemming from the analytical method [9].
The uncertainty stemming from variability in sample selection and collection needs to be
quantified or estimated to avoid undue efforts to eliminate insignificant analytical uncertainty,
while the sampling uncertainty remains substantial and unaddressed.

Measurement Quality Objectives (MQOs)

Measurement Quality Objectives are the QC requirements an analytical method must be able to
achieve to meet the goals of the project as expressed in the Data Quality Objectives. In selecting
18
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Dexsil L2000 PCB/Chloride Analyzer for Drum Surfaces
I CHARACTERIZATION TECHNOLOGIES, CONT'D. IffiiiiiliiliMliHliMBllimnill

a field technique for monitoring the drum cleanup process, DOE set criteria (the MQOs) to
reduce the risk of violating regulatory limits. These criteria were: (1) if field results are biased,
these must.be biased high (i.e., expected recoveries relative to the "true values" must be greater
than or equal to 100%), (2) the field technique should provide a rate of false negatives at less
than 10% at a 95% confidence limit, (3) the detection limit should be well below 5 ug/100 cm2,
and (4) the field technique should provide quantitative results in ug/100 cm2 (as opposed to
results in the form of a concentration range or interval). Of the 6 field methods evaluated during
the Environmental Technology Verification (ETV) project co-sponsored by EPA and DOE [3],
only the Dexsil test kit satisfied these criteria and was thus selected for monitoring the drum
cleaning process.

Analytical Data Quality Control

Quality control (QC) measures specified for the Dexsil field method are summarized in Table 1.
The laboratory utilized the QC measures discussed in EPA Method 8082.

The performance data collected during the ETV evaluation of the Dexsil PCB test kit [3] and the
data needs of the project were used to establish realistic expectations for the precision criteria hi
Table 1. It was recognized that measurement variability can be attributed to the following: (1)
analytical variability, as affected by operator proficiency and consistency, and by potential
variability hi extraction efficiency which depends on the nature of the materials collected by the
wipe sample, and (2) spatial variability or a heterogeneous distribution of the analyte across the
inside surfaces of the drum. Analytical variability due to operator proficiency and consistency is
monitored through the use of control charts on the'blank and standard results. In the ETV study,
replicate analyses of standards and well-mixed soils by the Dexsil field method showed relative
standard deviations (RSDs) of 14% and 23%, respectively [3], These RSDs, which correspond
to relative percent differences (RPDs) of 19% and 33% (RPD = ^2 RSD), were obtained under
near-ideal conditions of sample-to-sample homogeneity. The choice of the precision limit follows
from the discussion below setting the accuracy MQO.

Table 2. Performance characteristics of the Dexsil L2000 PCB/Chloride analyzer based on
the EPA/DOE ETV study [3] and DOE criteria for selecting a field method to monitor the
drum clean-up process [2].
Performance
Characteristics
Accuracy
Detection Errors
Detection limits
Measurement
range
Precision
Cost
ETV Study Result
Average recovery in soil samples was 208%.
Average recovery in simulated extract samples
(correspond best to wipe samples) was 149%.
PCBs were detected above the generic MDL for
four out of eight blank samples; there were no
false negative results.
The method detection limit (MDL) following the
EPA definition was 7.1 ppm. After
compensation for bias, the resulting MDL
agreed with Dexsil's specified MDL of 2 ppm.
The latter is numerically equivalent to 2 jag/100
cm2 of a 1,000 cm2 sample wipe area extracted
with 10 mL of isooctane.
Manufacturer-specified measurement range is
between 2 and 2,000 ppm. Quantitative results
were determined for extract samples with levels
of 10 and 100 ppm.
The overall precision based on relative standard
deviations (RSDs) was 23% for soil samples and
14% for extract samples.
Equipment purchase: $3,500;
$5 to $16 per sample (matrix dependent)
DOE Selection Criterion
If the field method is biased, it
must be biased high (i.e.,
recoveries must be a 100%).
There must be a low
probability of false negatives
using the field method.
The detection limit must be
less than the lowest action
level. The project-specific
MDL may be. defined by a
pilot study to address matrix
effects.
The field method should
provide quantitative results
around the critical values
selected for the project.
None specified.
None specified
22
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nw A i> A nTO^ * J?™Sil L200° PCB/Chloride Analyzer for Drum Surfaces
CHARACTERIZATION TECHNOLOGIES, CONT'D. 5SB55SS

a field technique for monitoring the drum cleanup process, DOE set criteria (the MQOs) to
SIS* ,£ v violating regulatory limits. These criteria were: (1) if field results are biased,
t^n? ,?Tnn t^?t' ^f CtCd recoveries relative t° the "true values" must be greater
f • i ShOUld Pr°vide a rate of false neSatives at less
, u • confldence hmit, (3) the detection limit should be well below 5 ug/100 cm2
and (4) the field technique should provide quantitative results in fig/100 cm2 (as opposed to
results in the form of a concentration range or interval). Of the 6 field methods evaluated during
the Environmental Technology Verification (ETV) project co-sponsored by EPA and DOE [3]
only the Dexsil test kit satisfied these criteria and was thus selected for monitoring the drum
cleaning process.

Analytical Data Quality Control

Quality control (QC) measures specified for the Dexsil field method are summarized in Table 1
1 ne laboratory utilized the QC measures discussed in EPA Method 8082.

The performance data collected during the ETV evaluation of the Dexsil PCB test kit [3] and the
data needs of the project were used to establish realistic expectations for the precision criteria in
lable i. It was recognized that measurement variability can be attributed to the following- (1)
analytical variability, as affected by operator proficiency and consistency, and by potential'
variability in extraction efficiency which depends on the nature of the materials collected by the
wipe sample, and (2) spatial variability or a heterogeneous distribution of the analyte across the
inside surfaces of the drum. Analytical variability due to operator proficiency and consistency is
momtored through the use of control charts on the blank and standard results. In the ETV study
replicate analyses of standards and well-mixed soils by the Dexsil field method showed relative
standard deviations (RSDs) of 14% and 23%, respectively [3]. These RSDs, which correspond •
to relative percent differences (RPDs) of 19% and 33% (RPD = V^RSD), were obtained under
near-ideal conditions of sample-to-sample homogeneity. The choice of the precision limit follows
rrom tne discussion below setting the accuracy MQO.

The lower accuracy limit (9.5 for the 10 ug/100 cm2 standard) was selected such that this value
would be rounded to the corresponding standard value. This corresponds to a lower recovery
limits of 95%, and ensures that field analytical results will not be biased low due to the
determinative step itself. The upper accuracy limits were derived from the recovery values
determined during the ETV demonstration [3]: the recovery for 10 ppm standards (equivalent to
the 10 ug/100 cm2 regulatory limit for the free-release scenario) was 207%, while the recovery
for 100 ppm standards was 91%. (Note that these recoveries were achieved in the absence of
other sources of variability in sample results, such as sampling heterogeneity or extraction
inefficiencies.) A recovery of 207% for a 10 ug/100 cm2 standard is 20 ug/100 cm2 and thus is
equivalent to 100% RPD. Since under the free-release scenario outlined in Box 3, all results
greater than 5 ug/100 cm2 are sent to the laboratory for confirmation testing anyway, using an
initial RPD of 100% is reasonable. If sample heterogeneity and analytical performance permit
more stringent limits on duplicate precision, this will be determined during the preparation of an
analytical control chart (see Table 1). '
19
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DexsH L2000 PCB/Chloride Analy
i CHARACTERIZATION TECHNOLOGIES, CONT'D.
Table 1. Analytical Data Quality Indicators (DQIs), Measurement Quality Objectives
(MQOs), and Corrective Actions for Dexsil Field Method __
Data Quality Indicator
(DQI) for Method
Measurement Quality Objective
(MQO)
Corrective Actions (if control limits are
exceeded)
Blanks: A field blank,
consisting of an unused wipe
or gauze pad soaked with 2
mL of chromatographic grade
hexane, will be analyzed by
the field method for every 20
field samples.
Blank results will not be greater
than the lowest action level (5.0
ug/100 cm2). Precision of blanks
will be less than 100% RSD.
All blanks will produce a numerical
result, therefore a project-specific
MDL is recommended.
Permissible rate of false positive
results*: the MDL must be
determined before the rate of false
positives can be evaluated.
The development and use of an
analytical control chart for blanks is
recommended: after obtaining 20-
30 blank results, the data is used to
calculate the mean and standard
deviation to prepare a control chart
to record subsequent blank results.
If a blank result exceeds 5.0 ug/100 cm2
or the 2 SD line of the control chart, a
second blank will be immediately run. If
that blank result is within the QC limits,
the method will be considered to be in
control. If the 2nd blank is also outside
control limits, troubleshooting ' of the
analyst and equipment will be performed
before other drum wipe samples are
analyzed.
Accuracy: A quality control
solution spiked at 10 ug/mL
(corresponds to 10 ug/100
cm2 regulatory limit for free
release) will be analyzed for
every 20 field samples.
For a 10 ug/100 cm2 standard, the
result must be *9.5 and
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Dexsil L2000 PCB/Chloride Analyzer for Drum Surfaces
I CHARACTERIZATION TECHNOLOGIES, rvwrm SBaaq^JBmim

Table 1. Analytical Data Quality Indicators (DQIs), Measurement Quality Objectives
MQOs), and Corrective Actions for Dexsil Field Method (continued).
Data Quality Indicator
(DQI) for Method
Measurement Quality Objective
(MQO)
Corrective Actions (if control limits are
exceeded)
Laboratory verification of
field analyses/Comparability:
During the initial and -
production phase of sampling,
10% and 5% respectively of
all field test kit results will be
verified by EPA SW-846
Method 8082. Under a
free-release decision tree, all
Dexsil results >5 will be
verified.
Field results will be compared to lab
results to ensure conservatism; that
is, most field results must be equal
to or higher than laboratory results.
If field results are trending lower
than lab results, a the project
statistician will be consulted to
determine whether trend is
significant (that is, the integrity of
the decision-making process is in
question). Corrective action will be
implemented if the statistician
believes it is necessary.
If other QC measures are acceptable, a
re-evaluation of the extraction step of the
field procedure will be undertaken to
identify correctable extraction
inefficiencies for this project-specific
matrix. If modification of the method
cannot ensure conservative results, yet the
bias appears to be predictable and
relatively constant, consultation with a
statistician will determine if the field
method-specific action level may be
adjusted to restore the desired margin of
safety.
1 Troubleshooting of the analyst will involve an experienced chemist observing the analyst to verify that correct
procedures are being followed during sample collection, extraction, and analysis. Tiered troubleshooting of. the •
equipment should be performed by an experienced chemist and will involve any of the following depending on the
nature of the problem: (1) evaluate sources of contamination: open a new box or lot of wipe pads, open a new lot of
hexane or extraction solvent, (2) evaluate blank or standard integrity: prepare fresh blank or standard solutions with
new solvent, (3) evaluate reagent/kit integrity: open a new Dexsil test kit box or lot, assess the condition and
performance of the chloride-specific electrode, (4) resumption of drum sampling will not resume until acceptable
performance of the field method is obtained.
* A false negative result is one where the analyte is not detected above the reporting limit when it is actually
present above the reporting limit. A false positive result is one where the analyte is detected above the reporting
limit when it is not actually present.
One other factor needs to be considered when setting the initial upper limit on the 10 ug/100 cm2
standard: the standard used in this project is Aroclor 1260, yet the Dexsil instrument was set to
report its readings as Aroclor 1242, which will additionally bias the results high. So a reasonable
starting value for the upper limit on the field QC standard is 30 ug/100 cm2. This value can be
adjusted during the project if warranted by the applicable analytical control chart. Just as the
process control charts monitor possible drifting of performance that signals the need for re-
optimization of process parameters, so too, the use of analytical control charts continually
monitor the analytical method for instrument drift or other causes of deteriorating analytical
performance.

The laboratory method selected for verifying the field analyses was SW-846 Method 8082,
Polychlorinated Biphenyls (PCBs) by Capillary Column Gas Chromatography (GC/ECD). The
wipe samples for lab analysis were immediately immersed hi 10 mL of hexane and transported to
the fixed laboratory where aliquots of the hexane extracts were injected into the GC/ECD for
PCB quantification. Thus, the laboratory and field methods were different in the following
aspects: (1) extraction solvent (hexane vs isooctane), (2) length of time for extraction solvent
exposure, and (3) determinative technique (GC/ECD vs. ion-specific electrode).
21
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Dexsil L2000 PCB/Chloride Analyzer for Drum Surfaces
I CHARACTERIZATION TECHNOLOGIES, CONT'D. \
An extensive evaluation of several PCB field technologies was performed under the ETV
program co-sponsored by EPA and DOE. Table 2 lists the performance characteristics obtained
from the ETV evaluation of the Dexsil PCB kit [3], and illustrates that the Dexsil PCB kit met
the criteria set by DOE for selecting a field method to monitor the drum clean-up process.

Table 2. Performance characteristics of the Dexsil L2000 PCB/Chloride analyzer based on
the EPA/DOE ETV study [3] and DOE criteria for selecting a field method to monitor the
drum clean-up process [2].
Performance
Characteristics
Accuracy
Detection Errors
Detection limits
Measurement
range
Precision
Cost
ETV Study Result
Average recovery in soil samples was 208%.
Average recovery in simulated extract samples
(correspond best to wipe samples) was 149%.
PCBs were detected above the generic MDL for
four out of eight blank samples; there were no
false negative results.
The method detection limit (MDL) following the
EPA definition was 7.1 ppm. After
compensation for bias, the resulting MDL
agreed with Dexsil' s specified MDL of 2 ppm.
The latter is numerically equivalent to 2 ug/100
cm2 of a i,000 cm2 sample wipe area extracted
with 10 mL of isooctane.
Manufacturer-specified measurement range is
between 2 and 2,000 ppm. Quantitative results ,
were determined for extract samples with levels
of 10 and 100 ppm.
The overall precision based on relative standard
deviations (RSDs) was 23% for soil samples and
14% for extract samples.
Equipment purchase: $3,500;
$5 to $16 per sample (matrix dependent)
DOE Selection Criterion
If the field method is biased, it
must be biased high (i.e.,
recoveries must be s 100%).
There must be a low
probability of false negatives
using the field method.
The detection limit must be
less than the lowest action
level. The project-specific
MDL may be. defined by a
pilot study to address matrix
effects.
The field method should
provide quantitative results
around the critical values
selected for the project.
None specified.
None specified
22
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Dexsil L2000 PCB/Chloride Analyzer for Drum Surfaces
I PERFORMANCE EVALUATION SSSSSSS^ , \m m MMga

Sampling Results and Cleaning Process Performance •

Over a period of four days, the drum-cleaning technology vendor was permitted to treat 20 to 25
drums to optimize the cleaning process. During this trial period, the Dexsil PCB test kit was
used to monitor residual PCB surface levels in the processed drums. Some of the drams were re-
cleaned and re-sampled several times for a total of 27 field samples. The field testing provided
immediate feedback regarding the effectiveness of the cleaning process, and showed that the
process was unable to consistently and reliably achieve the action limit of 5 ^g/100 cm2 (see
Table 3,[6]). Even reproducibly achieving an action limit of 50 ug/100 cm2 (appropriate for the
metal smelting goal) proved difficult, with several drums exceeding 2,000 ugVlOO cm2 of residual
contamination. During the fkst day of the trial period, five out of six drums had residual levels
greater than 200 ug/100 cm2. Corresponding laboratory measurements later confirmed the field
test results (see Table 3). On the fourth and last day of the trial period, six out of eight drums
had residual levels measured by the Dexsil test kit as exceeding 200 ug/100 cm2, with some
levels exceeding 2,000 ug/100 cm2. These field results were also confirmed by laboratory
analysis (see Table 3). At this point, DOE aborted the project before additional resources were
expended on a dram cleaning process that was clearly not working. The production phase of the
sampling workplan described previously was never implemented.

Table 3. Residual PCB levels in processed drums measured using the Dexsil L2000
PCB/chloride analyzer and EPA SW-846 Method 8082 [6].
100 cm2 as Aroclor 1242
4.8
11
1254
>200
5.397
1254
>200
2,123
1254
>200
1,169
1254
>200
L857
1254
JulyS, 1998
>200
6.3
1,810
NP
1254
3.9
NP
3.8
NP
4.8
NP
7.8
23
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Dexsil L2000 PCB/Chloride Analyzer for Drum Surfaces
I PERFORMANCE EVALUATION, CONT'D.I
The comparability MQO (laboratory verification analyses) was evaluated by comparing the field
results with the corresponding ten laboratory analyses. In general, the lab analyses were
consistent with the field method results when compared against the field action level of 5 fig/100
cm2 (see Table 3), although the desired MQO that the field results be at least as high, or higher,
than the lab results (to maintain conservative decision-making in the field) was not achieved in
this initial limited data set. Had this project continued, corrective action would have been
performed before implementing the applicable decision tree.

A previous evaluation of the Dexsil PCB test kit (the ETV study) showed that results strongly
tend to be biased high with average recoveries of 149% for'simulated extract samples at
concentrations of 10 and 100 ug/100 cm2 [3]. This bias was evident in this project in that the 10
fig/100 cm2 standard had recoveries up to 260%, as discussed previously. However, the data set
in Table 3 suggests that the Dexsil results are biased low compared to the laboratory results.
Further, even lower results would be expected had the Dexsil analyzer been set to report results
as Aroclor 1260 (the Aroclor occasionally reported by the laboratory method and closer in
chlorine content to Aroclor 1254, which was the Aroclor most reported by the laboratory),
instead of Aroclor 1242. Reporting of Dexsil results as Aroclor 1242 was chosen to add
additional conservatism to the field results. Therefore, it is surprising that the quantitative Dexsil
results underestimated the confirmatory laboratory results. One can speculate that this negative
bias may be due to a less efficient extraction of PCBs from the matrices collected on the wipe
pads using isooctane as compared to hexane, which was the solvent used for Method 8082. In
the ETV study, wipe sample extracts were simulated by the use of spiked solvent aliquots, and as
a consequence, the efficiency of isooctane for extracting PCBs collected on wipes/gauze pads
was not evaluated. Extraction efficiency differences may be further exacerbated if the wipes are
saturated with oily residues, i.e., hexane may be more effective at extracting PCBs from viscous
residues than isooctane. In addition to differences in solvent, the extraction times were also
drastically different between the field and laboratory methods. The wipes were extracted for
only 30 seconds using the Dexsil method, While the wipes for laboratory analyses were immersed
in hexane for a much longer time as they were transported to the fixed analytical laboratory.

Another potential reason for the bias may be reflected in the sequence in which the laboratory
and field wipe sample duplicates were collected. Since a 1,000 cm2 area was required for each
wiper-sampling, it was difficult to allocate accurately delineated non-overlapping sample areas for
the field and lab samples due to the size of the drums. If the laboratory wipe samples were
collected first and the field sample areas overlapped with the lab sample areas, it is possible that
the laboratory wipe samples would have demonstrated higher PCB levels.

Had the cleaning procedure proved effective and the project gone forward, any significant
negative bias between field and laboratory results would have been addfessed by
troubleshooting.
26
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Dexsil L2000 PCB/Chloride Analyzer for Drum Surfaces
I PERFORMANCE EVALUATION I ~

Sampling Results and Cleaning Process Performance

Over a period of four days, the drum-cleaning technology vendor was permitted to treat 20 to 25
drams to optimize the cleaning process. During this trial period, the Dexsil PCB test kit was
used to monitor residual PCB surface levels in the processed drams. Some of the drams were re-
cleaned and re-sampled several times for a total of 27 field samples. The field testing provided
immediate feedback regarding the effectiveness of the cleaning process, and showed that the
process was unable to consistently and reliably achieve the action limit of 5 ug/100 cm2 (see
Table 3,[6]). Even reproducibly achieving an action limit of 50 ug/100 cm2 (appropriate for the
metal smelting goal) proved difficult, with several drums exceeding 2,000 ug/100 cm2 of residual
contamination. During the first day of the trial period, five out of six drams had residual levels
greater than 200 ug/100 cm2. Corresponding laboratory measurements later confirmed the field
test results (see Table 3). On the fourth and last day of the trial period, six out of eight drams
had residual levels measured by the Dexsil test kit as exceeding 200 ug/100 cm2, with some
levels exceeding 2,000 ug/100 cm2. These field results were also confirmed by laboratory
analysis (see Table 3). At this point, DOE aborted the project before additional resources were
expended on a dram cleaning process that was clearly not working. The production phase of the
sampling workplan described previously was never implemented.
Table 3. Residual PCB levels in processed drums measured using the Dexsil L2000
PCB/chloride analyzer and EPA SW-846 Method 8082 [6].
Sample ID
Dexsil Test Method
Method 8082
100 cm2 as Aroclor 1242
4.8
11
1254
>200
5,397
1254
>200
2.123
1254
>200
1,169
1254
>200
1.857
1254
July 8, 1998
4
3.9
3.8
4.8
7.8
NP
_NP_
NP
NP
NP
23
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Dexsil L2000 PCB/Chloride Analyzer for Drum Surfaces
I PERFORMANCE EVALUATION, CONT'D.HHB^HHpHHB^HHHi^S

Table 3. Residual PCB levels in processed drums measured using the Dexsil L2000
PCB/chloride analyzer and EPA SW-846 Method 8082 [6] (continued).
Sample ID
Dexsil Test Method1
Method 8082
/100 cm2 as Aroclor 1242
/100cm2 I Aroclor2
My 9.1998
>100
NP
14.1
NP
22.0
NP
4.0
NP
3.9
NP
82.7
NP
3.8
July 15.1998
>200
NP
>200
NP
>200
NP
>2,000
17,749
1254
> 1,000
NP
3.2
1260
9.8
26.3
1254
8
>1.000
19J398
1260
'Although the Dexsil analyzer is capable of reporting quantitative results up to 2,000 ug/100 cm2, field results during
this phase of the project were reported quantitadvely only if the levels were below 100 ug/100 cm2. Over 100 ug/100
cm2, the results were reported variously as ">100", ">200", ">1,000" or ">2,000".
2 Aroclor identified in sample based on relative amounts of PCB congeners detected.
NP = Not Performed (No sample sent for laboratory confirmation.)

Performance of Analytical Technology

The performance of the Dexsil test kit can only be evaluated based on the limited data set that
was collected before the clean-up project was aborted [6]. Table 4 shows the results of the field
blanks and of the 10 ug/100 cm2 standards used as QC samples. The field blank results are
comparable to those measured during the ETV evaluation of the Dexsil test kit [3] where the
average PCB level measured in unspiked simulated extract samples (analogous to field blanks)
was 2.3 ppm.
24
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DexsH L2000 PCB/Chloride Analyzer for Drum Surfaces
I PERFORMANCE EVALUATION, CONT'D.i

Table 4. Field analytical results of quality control samples [6].
Quality Control Sample
Field Method Result
(ug/100 cm2 reported as
Aroclbr 1242)
Blanks
Analyzed on July 7,1998
Applicable MQO
(from Table 1)
(ug/100 cm2)
<5.0
Analyzed on July 8,1998
0.6
<5.0
Analyzed on July 9,1998
3.1
<5.0
Analyzed on July 9,1998
1.0
<5.0
Analyzed on July 13,1998
2.3
<5.0
Analyzed on July 14,1998
3.7
<5.0
Analyzed on July 15,1998
2.4
<5.0
Summary of Blank Performance
Mean (*) = 2.5; SD= 1.0
Precision (RSD): 40%'
10 ug/100 cm2 Arochlor 1260
Standard
Analyzed July 7,1998
26.3
Establish Control Chart
RSDslOO% :
and
Analyzed July 8,1998
11.8
and s30
Analyzed July 9, 1998
21.0
29.5 and s30
Analyzed July 13,1998
23.8
and <;30
Analyzed July 14.1998
24.1
and <:30
Analyzed July 15,1998
12.6
:>9.5 and
Summary of Standard Performance
Mean (*) = 19.9; SD = 6.2
Accuracy (as % recovery): 199%
Precision (RSD): 31 %
Establish Control Chart
In this study, the mean was 2.5 ppm, and the precision for the blank readings was 40%. Analysis
of the QC standard samples showed that false negatives at the regulatory control limit of 10
ug/100 cm2 are unlikely. All recoveries for the 10 ng/100 cm2 standard samples were, greater
than 100%. The high recoveries are consistent with the ETV study [3] which showed that the
Dexsil test results were biased high in both soil and simulated extract samples. .High recoveries
in this study are also expected because Aroclor 1260 was used for the QC standard, yet the
Dexsil kit was set to report the result as Aroclor 1242. The precision of the Dexsil kit for the 10
fig/100 cm2 QC standard was 31%. The.precision of neither the Dexsil test kit nor the laboratory
method with respect to the actual samples could be evaluated from the data set because no field
duplicates were collected. .
25
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Dexsil L2000 PCB/Chloride Analyzer for Drum Surfaces
[PERFORMANCE EVALUATION, CONT'D.«B«
The comparability MQO (laboratory verification analyses) was evaluated by comparing the field
results with the corresponding ten laboratory analyses. In general, the lab analyses were
consistent with the field method results when compared against the field action level of 5 ug/100
cm2 (see Table 3), although the desired MQO that the field results be at least as high, or higher,
than the lab results (to maintain conservative decision-making in the field) was not achieved in
this initial limited data set. Had this project continued, corrective action would have been
performed before implementing the applicable decision tree.

A previous evaluation of the Dexsil PCB test kit (the ETV study) showed that results strongly
tend to be biased high with average recoveries of 149% for 'Simulated extract samples at
concentrations of 10 and 100 ug/100 cm2 [3]. This bias was evident in this project in that the 10
ug/100 cm2 standard had recoveries up to 260%, as discussed previously. However, the data set
in Table 3 suggests that the Dexsil results are biased low compared to the laboratory results.
Further, even lower results would be expected had the Dexsil analyzer been set to report results
as Aroclor 1260 (the Aroclor occasionally reported by the laboratory method and closer in
chlorine content to Aroclor 1254, which was the Aroclor most reported by the laboratory),
instead of Aroclor" 1242. Reporting of Dexsil results as Aroclor 1242 was chosen to add
additional conservatism to the field results. Therefore, it is surprising that the quantitative Dexsil
results underestimated the confirmatory laboratory results. One can speculate that this negative
bias may be due to a less efficient extraction of PCBs from the matrices collected on the wipe
pads using isooctane as compared to hexane, which was the solvent used for Method 8082. In
the ETV study, wipe sample extracts were simulated by the use of spiked solvent aliquots, and as
a consequence, the efficiency of isooctane for extracting PCBs collected on wipes/gauze pads
was not evaluated. Extraction efficiency differences may be further exacerbated if the wipes are
saturated with oily residues, i.e., hexane may be more effective at extracting PCBs from viscous
residues than isooctane. In addition to differences in solvent, the extraction times were also
drastically different between the field and laboratory methods. The wipes were extracted for
only 30 seconds using the Dexsil method, While the wipes for laboratory analyses were immersed
in hexane for a much longer time as they were transported to the fixed analytical laboratory.

Another potential reason for the bias may be reflected in the sequence in which the laboratory
and field wipe sample duplicates were collected. Since a 1,000 cm2 area was required for each
wipe-sampling, it was difficult to allocate accurately delineated non-overlapping sample areas for
the field and lab samples due to the size of the drums. If the laboratory wipe samples were
collected first and the field sample areas overlapped with the lab sample areas, it is possible that
the laboratory wipe samples would have demonstrated higher PCB levels.

Had the cleaning procedure proved effective and the project gone forward, any significant
negative bias between field and laboratory results would have been addr'essed by
troubleshooting.
26
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Dexsil L2000 PCB/Chioride Analyzer for Drum Surfaces
icosT COMPARISON!
Table 5 lists estimated costs for the testing program that DOE had planned for verifying the drum
cleanup process. The calculations in this table assume that approximately 400 wipe samples will
be analyzed (7,000 drums processed in 14 batches of 500 from which 28 are wipe sampled). For
400 wipe samples, at least 60 QA/QC samples (blanks, standards and replicates) would have
been required according to the sampling plan using the Dexsil test kit. It is assumed that the
same number of QA/QC samples would have been required if a laboratory method were used.
The sampling program using the field.method also includes laboratory verification of 40 samples
(10%), assuming that with an effective cleaning program, few field analyses would have
exceeded the criteria of the decision tree requiring additional laboratory confirmation. Under
ideal circumstances, the total cost of the sampling program using the Dexsil kit (including the
purchase of .the Dexsil analyzer) is less than 50% of a similar program using a laboratory method.
Had this project been executed to completion, considerable savings would have resulted from the
use of the field method for clean-up verification with the added benefit of immediate turn-around
of results.

Although the sampling program was not completed, use of the Dexsil test kit during the vendor's
trial period was clearly advantageous for DOE because rapid feedback was provided to the clean-
up technology vendor that the process was not working. The immediate availability of analytical
results also allowed DOE to rapidly reach a decision to abort the project, thereby avoiding
expending more resources and accumulating more liability to the vendor;

Table 5. Comparison of costs for a sampling program using the Dexsil PCB field method
and EPA Method 8082.
Cost Element
Equipment cost (capital)
Analysis of samples
Analysis of QA/QC samples
Analysis of laboratory
verification samples
TOTAL
Dexsil PCB Method
$3,500
$12.50 x 400 samples =
$5,000
$12.50 x 60 samples = $750
$50 x 40 samples = $2,000
$11,250
EPA Method 8082
$0
$50 x 400 samples = $20,000
$50 x 60 samples = $3,000
$0
$23,000
27
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28
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, Dexsil L2000 PCB/Chloride Analyzer for Drum Surfaces
I OBSERVATIONS AND LESSONS LEARNEDBnanS^SSSBS

Because the project was aborted during its initial phase and the full sampling program was never
implemented, this case study represents a very limited data set from which to draw observations
and lessons learned in using the Dexsil PCS field method. However, the case study does
illustrate that the use of a field method enabled rapid decision-making by the data users. The
benefits of the field PCB method are identified as follows [6]:

• blank QC samples showed no false negative analytical results (a false negative analytical
result is one where the analyte is not detected when it is actually present);
• reduced per sample costs ($12.50 per sample vs. approximately $50 per sample using
Method 8082); and
• rapid turn-around for results (within an hour of the last sample taken).

Use of the field method proved itself by immediately identifying to DOE that the process was not
working as expected. Therefore, the process was stopped before DOE had assumed a larger
liability [6].

Lesson learned concerning process control tools:

• Depending on how the first 50 samples used to prove process effectiveness are distributed,
x + 2SD and x + 3SD could possibly be greater than the action limit. If this were true,
then the statistical control charts may be superfluous.

Lesson learned concerning the analytical QA/QCplan:

• Had the project gone forward, the value of a detailed, well-planned and documented
quality assurance plan would have been vital to detecting, correcting or compensating for
any matrix interferences or other problems related to non-representative sampling and
analysis. (On the other hand, had the cleaning procedure worked, matrix problems would
not have existed, since the contaminated matrix would have been removed.) Detailed QA
plans and project-specific standard operating procedures (SOPs) are critical to
implementing field analytical methods to produce reliable data which supports defensible
decision-making. Clearly defined MQOs and corrective measures ensure that field
analytical data will be of known and documented quality.

• If a project's data defensibility depends partly on good comparability between laboratory
and field measurements, representative sampling and analysis issues must be addressed, or
the data will not be able to support project decision-making.

• Although much of the technical detail of rigorous QA plans may seem complex, designing
and implementing statistically valid analytical quality assurance plans is a routine matter
for experienced analytical chemists and statisticians. Tapping into appropriate expertise
during project planning, and then at critical junctures during execution, will substantially
increase the likelihood that projects will successfully meet the goals of public safety and
confidence.
29
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Dexsil L2000 PCB/Chloride Analyzer for Drum Surfaces
i REFERENCES i

1. East Tennessee Technology Park Overview -.Mission - Vision - Environmental Management
and Enrichment Facilities Programs - History;
http://www.ornl.gov/K25/techdemo/ettpover.htm; posted May, 1997.

2. Letter from Winston A. Smith of EPA Region 4 to Suzanne P. Riddle of DOE dated April 20,
1998. Enclosure: Sampling and Analysis Plan Certification of Cleanliness for Empty TSCA
Drums, Revision 1, DOE Oak Ridge Operations, Environmental Management Technical
Services Team.

3. Dindal, A.B.; Bayne, C. K.; Jenkins, R. A.; Billets, S.; Koglin, E. N. Environmental
Technology Verification Report: Electrochemical Technique/Ion Specific Electrode, Dexsil
Corporation, L2000 PCB/Chloride Analyzer. Environmental Protection Agency,
EPA/600/R-98/109, August 1998.

4. Walpole, R.; Myers, R. H. Probability and Statistics for Engineers and Scientists. New
York: MacMillan Publishing Co., Inc., 1978.

5. U.S. Environmental Protection Agency Environmental Response Team, Standard Operation
Procedures #2011, Chip, Wipe and Sweep Sampling, Rev. 0.0. November 1994.

6. Memorandum from Chip Davis, PCB Field Screening Coordinator for DOE, to Brian
Demonia and David Garden, DOE Program Managers, October 23, 1998.

7. Gibbons, Robert D. Statistical Methods for Groundwater Monitoring. New York. John
Wiley & Sons, Inc., 1994.

8. U.S. Environmental Protection Agency, 1986 and updates, Test Methods for Evaluating Solid
Waste-Physical/Chemical Methods, EPA Publication SW-846, Chapter 9, Office of Solid
Waste, Washington, D.C.

9. Jenkins, T.F., et al. Assessment of Sampling Error Associated with Collection and Analysis of
Soil Samples at Explosives-Contaminated Sites. US Army Corps of Engineers Cold Regions
Research and Engineering Laboratory. Special Report 96-15. September 1996.
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