United States
Environmental Protection
Agency
Office of Air Quality
Planning and Standards
Research Triangle Park NC 27711
EMB Report 85-CHM-10
December 1985
Air
Neshap Screening
Study
Chromium
Emission Test
Report
C. S. Ohm
Manufacturing
Company
Sterling Heights, Ml
-------
EMISSION TEST REPORT
C. S. OHM MANUFACTURING COMPANY
STERLING HEIGHTS, MICHIGAN
ESED 85/02
EMB 85-CHM-10
by
Entropy Environmentalists,
Post Office Box 12291
Research Triangle Park, North Carolina 27709
Contract No. 68-02-3852
Work Assignments No. 18, 21, and 23
PN: 3023
EPA Task Manager
Dan Bivins
U. S. ENVIRONMENTAL PROTECTION AGENCY
EMISSION MEASUREMENT BRANCH
EMISSION STANDARDS AND ENGINEERING DIVISION
RESEARCH TRIANGLE PARK, NORTH CAROLINA 27711
January 1986
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CONTENTS
Page
Figures iv
Tables v
1.0 INTRODUCTION 1-1
2.0 PROCESS OPERATION 2-1
2.1 Process Description 2-1
2.2 Air Pollution Control 2-3
2.3 Process Conditions During Testing 2-4
3.0 SUMMARY OF RESULTS 3-1
3.1 Particulate Matter, Hexavalent Chromium and Total Chrcmiun 3-3
3.1.1 Scrubber Inlet (EPA Method 5) 3-3
3.1.2 Scrubber Inlet (Impinger Train) 3-7
3.1.3 Scrubber Outlet 3-8
3.2 Emissions in Units of Process Rate and Control Equipment
Collection Efficiency 3-9
3.2.1 Emissions in Units of Process Rate 3-9
3.2.2 Control Equipment Collection Efficiency 3-11
3.3 Summary of Analytical Results for Hexavalent and
Total Chromium 3-11
4.0 SAMPLING LOCATIONS AND TEST METHODS 4-1
4.1 Scrubber Inlet (Sampling Location A) 4-1
4.2 Scrubber Outlet (Sampling Location B) 4-5
4.3 Velocity and Gas Temperature 4-5
4.4 Molecular Weight 4-7
4.5 Particulate Matter 4-7
4.6 Impinger Collection Efficiency 4-8
4.7 Hexavalent Chrcmiun Content 4-8
4.8 Total Chromiun Content 4-9
5.0 QUALITY ASSURANCE 5-1
11
-------
CONTENTS (Continued)
APPENDICES
A TEST RESULTS AND EXAMPLE CALCULATIONS A-1
Particulate, Hexavalent Chrcmiun and Total Chrcmiun A-3
Example Particulate Test Calculations A-15
Total Chromiun Analysis Calculation A-28
Explanation of Total Chromiun Analysis Calculation Table A-29
B FIELD AND ANALYTICAL DATA B-1
Particulate Matter B-3
Total Particulate Analysis B-21
Hexavalent Chromiun Analysis B-27
Total Chromiun Analysis B-31
C SAMPLING AND ANALYTICAL PROCEDURES C-1
Determination of Total Particulate Emissions C-3
Determination of Hexavalent Chromiun Emissions C-8
Determination of Total Chromium Content C-15
D CALIBRATION AND QUALITY ASSURANCE DATA D-1
E MRI PROCESS DATA E-1
Source Sampling Program - Process Data Sheets E-3
Current Usage Calculations E-6
F TEST PARTICIPANTS AND OBSERVERS F-1
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FIGURES
Number Page
2-1 Sequence of tanks on the decorative plating line at C. S. Ohm
Manufacturing Company 2-2
4-1 Diagram of decorative chromiun plating line and emissions
control system at C. S. Ohm Manufacturing Company 4-2
4-2 Scrubber Inlet (Sampling Location A) 4-4
4-3 Scrubber Outlet (Sampling Location B) 4-6
iv
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TABLES
Number Page
2.1 Total Current Supplied to Tank During Source Tests 2-5
3.1 Testing Schedule for C. S. Ohm 3-2
3.2 Summary of Flue Gas Conditions 3-4
3.3 Summary of Particulate, Hexavalent Chromium, and Total
Chromiun Emissions 3-6
3.4 Summary of Emission Rates in Units of Process Rate and
Efficiency 3-10
3.5 Summary of Analytical Results for Hexavalent and Total
Chromiun 3-12
3.6 Summary of Analytical Results for Hexavalent and Total
Chromiun Quality Assurance Samples 3-14
4.1 Sampling Plan for C. S. Ohm 4-3
5.1 Field Equipment Calibration 5-2
5.2 Audit Report Chromiun Analysis 5-4
v
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1.0 INTRODUCTION
During the week of June 17-21, 1985, Entropy Environmentalists, Inc.
conducted an emission measurement program at C. S. Ohm Manufacturing Company's
chromium plating plant located in Sterling Heights, Michigan. The purpose of
this program was to provide data for a screening study to determine the
quantity and form of chromium emissions associated with decorative chromium
plating.
Comprehensive testing was conducted on a decorative chromiun plating tank
whose emissions are controlled by a packed-bed wet scrubber. This fume
scrubber controlling emissions from the decorative chromiun plating tank at the
plant was selected for source testing for the following reasons:
The plating tank appears to be typical of other automated
decorative plating tanks in the chromiun plating industry, based
on operating parameters such as temperature, current, voltage,
and plating time. The automatic hoist is programmed to change
the rack in the chromiun plating tank every 4.5 minutes.
Electrolysis occurs in this tank for 1.5 minutes during each
cycle, or 33 percent of the time. A demisting agent called
MSP-1, manufactured by Harshaw Chemicals, is used in the tank to
suppress misting. The use of demisting agents is common practice
for decorative platers.
The emissions capture system is highly efficient in directing
fuses from the plating tank to the control device. The tank is
equipped with a push-pull ventilation system that draws 16,000
scfm across a total tank surface area of 90 ft . (Included in
this area is a storage tank used to concentrate chromic acid
solutions from the rinse tank and the fune scrubber. No
electrolysis occurs in this tank.)
The emissions control device used at C. S. Ohm is typical of
control devices in use at other decorative plating facilities.
Most decorative plating facilities use impingement-type mist
eliminators or packed-bed fune- scrubbers to control chromic acid
emissions. Emission data from testing at the outlet of the Viron
wet packed-bed fune scrubber at this facility will represent
emissions controlled by a typical fune scrubber.
1-1
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Particulate concentrations and mass emission rates were measured at
the scrubber inlet and outlet using U. S. Environmental Protection Agency
(EPA) Reference Method 5.* Total chromium concentrations and hexavalent
chromium concentrations were measured at the same locations by further
analysis of the Method 5 samples using the alternate sample preparation
and analytical procedures as described in Appendix C. Flue gas flow
rates, temperature, moisture content, and composition [oxygen (02)/ carbon
dioxide (CC^)/ and carbon monoxide (CO)] were measured in conjunction with
the particulate tests. In addition, an impinger train was run concurrent with
the Method 5 train at the scrubber inlet to determine impinger collection
efficiency for total and hexavalent chromium. And for approximately 8 1/2
hours on the second day of testing, a special high volume, constant rate,
single point sampling run was conducted at the scrubber inlet using a Method 5
train.
Ms. Barbara Duletsky [Midwest Research Institute (MRI)] monitored process
operation throughout the test period. Mr. Dan Bivins (EPA Task Manager) of the
Emission Measurement Branch (EMB) and Mr. Al Vervaert of the Industrial Studies
Branch (ISB) observed the test program. Mr. Robert Waters, Plating Plant
Manager served as the contact for C. S. Ohm Manufacturing.
This report is organized into several sections addressing various aspects
of the testing program. Immediately following this introduction is the
"Process Operation" section which includes a description of the process and
control device tested. Following this is the "Summary of Results" section
which presents table summaries of the test data and discusses these results.
The next section, "Sampling Locations and Test Methods" describes and
*40 CFR 60, Appendix A, Reference Method 5, July 1, 1980.
1-2
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illustrates the sampling locations for emissions testing and then explains the
sampling strategies used. The final section, "Quality Assurance," notes the
procedures used to ensure the integrity of the sampling program. The
Appendices present the complete Test Results and Example Calculations (Appendix
A); Field and Analytical Data (Appendix B); Sampling and Analytical Procedures
(Appendix C); Calibration Data (Appendix D); MRI Process Data (Appendix E)j and
Test Participants and observers (Appendix F).
1-3
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2.0 PROCESS OPERATION
2.1 PROCESS DESCRIPTION
The C. S. Ohm Manufacturing Company manufactures bumpers for use in
the automotive industry. The company has a captive plating shop that
performs decorative nickel-chromium plating of the bumpers. The plat-ing
plant operates 24 hours per day, 6 days per week, 52 weeks per year, with
the exception of Wednesday mornings from midnight to-6:00 a.m., when the
operation ceases for maintenance purposes.
The decorative plating line consists of 36 tanks that contain various
plating and cleaning solutions. The sequence of tanks is shown in
Figure 2-1. The line is serviced by an automatically controlled hoist
that transfers each rack of bumpers through the various tanks in the
plating line.
The chromium plating segment of the line is comprised of one plating
tank, one evaporation tank, and three rinse tanks. Emissions from the
chromium plating tank were measured during this source test program. The
tank measures 3.0 meters (m) (10 feet [ft]) in length, 1.4 m (4.5 ft) in
width, 2.4 m (8 ft) in depth, and holds 10,600 liters (i) (2,800 gallons)
of plating solution. The solution contains chromic acid in a
concentration of 330 to 340 grams per liter (gA) (44 to 46 ounces per
gallon [oz/gal]). This is in the range of 220 to 370 g/i (30 to
50 oz/gal) typically used by decorative chromium platers. Sulfuric acid
is used in the solution as a catalyst in a concentration of 1.0 to 1.2 g/2,
(0.14 to 0.16 oz/gal). The proper concentration of constituents is
maintained by adding chromic acid and sulfuric acid every other day, and
by adding make-up solution from the evaporation tank on alternate days.
The total chromic acid consumption at C. S. Ohm is about 8,200 kilograms
(18,000 pounds) per year.
Typically, a rack remains in the chromium plating tank for 4 minutes
and 20 seconds. The normal operating temperature of the tank is between
46° and 63°C (115° and 145°F). The electrodes are charged by a single
transformer/rectifier set that automatically controls the operating
voltage and current. During a typical plating cycle, the tank operates at
2.5 volts (V) and 1,500 amperes (A) for 15 seconds to activate the
nickel-plated surfaces. Then, the voltage increases to 12.4 V and the
2-1
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Tank
sequence Description
1 Soap tank
2 Power spray
3 Electro-cleaner No. 1
4 Electro-cleaner No. 2
5 Water rinse
6 Water rinse
7 Anodic etch (contains H2)
Anodic etch (contains H2)
8 Rinse
9 Rinse
10 Rinse
11 Electro-cleaner No. 3
12 Rinse
13 Muriatic acid
14 Rinse
15 Nickel strike
16 Dull nickel plate
Dull nickel plate
Dull nickel plate
Dull nickel plate
Dull nickel plate
Dull nickel plate
Dull nickel plate
Dull nickel plate
17 Bright nickel plate
Bright nickel plate
18 Micro-porous (MP) nickel plate
19 Nickel reclaim
20 Rinse
21 Activator chrome
Chromium plate (evaporation tank)
22 Chromium plate
23 Chromic acid reclaim
24 Rinse
25 Rinse
26 Hot water rinse
Figure 2-1. Sequence of tanks on the decorative plating line
at C. S. Ohm Manufacturing Company
2-2
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current Increases to 12,000 to 16,000 A for 90 seconds, during which
chromium is deposited on the activated surfaces. This 90-second period is
called "electrolysis." The current required during electrolysis is
dependent on the surface area being plated and is automatically adjusted
for each new rack of bumpers.
2.2 AIR POLLUTION CONTROL
A fume suppressant called "MSP-1" is used in the chromium plating
tank to inhibit the release of gases generated during electrolysis. The
suppressant is manufactured by Harshaw Chemical Company. It contains a
fluorocarbon that decreases the surface tension of the plating solution,
thus, decreasing the generation of mist. There are no test data available
showing the emission reduction achieved by using this fume suppressant,
although it is used commonly in the electroplating industry to preclude
misting.
The chromium plating tank and evaporation tank are equipped with a
push-pull ventilation system. Air jets on one end of the tanks push mist
across the plating solution to a 1.2-m-high (4-foot-high) hood on the
other end. An induced draft fan driven by a 20-horsepower motor draws
emissions away from the tanks to the control device.
The control device is a wet, double-packed-bed scrubber manufactured
by Viron International (Model HSDP-2000). The scrubber is designed to
treat about 7.6 cubic meters per second (m?/s) (16,765 standard cubic feet
per minute [scfm]) of plating tank exhaust gases. Chromic acid is removed
from the gas stream by impacting on two 30-cm-deep (12-inch-deep) beds of
filter media that are continuously sprayed with scrubbing liquid. The
spent liquid drains into a remote holding tank from which it is
recirculated through the scrubber. The holding tank is emptied once every
2 or 3 days and refilled with fresh water. The holding tank has an
estimated volume of 500 i (132 gal) and pumps about 91 a/min (24 gal/min)
of liquid to the scrubber.
The scrubber also contains a mist eliminator stage for the final
removal of liquid droplets from the gas.stream. This stage consists of a
"Chevron-type" arrangement of baffles that change the direction of gas
2-3
-------
flow several times. The entire scrubbing unit has a design removal
efficiency of 99 percent for chromic acid.
2.3 PROCESS CONDITIONS DURING TESTING
The process was operating normally during the source test program.
Process operating parameters such as temperature, voltage, and current
were monitored during each test run and are recorded on the process data
sheets in Appendix E. No operating parameters were monitored for the
scrubber; however, there were no indications of any malfunction in the
system during the testing.
Normal operating conditions allowed all three test runs to be
performed without interruption. A scheduled 10-minute break in operation
occurred each day at 10:30 a.m., but this was not considered cause to
suspend testing because it was of short duration. Inlet and outlet
testing were performed simultaneously.
The total current supplied to the tank during each test run is
calculated in terms of ampere-seconds and included in Appendix E. A
summary of the total current values is presented in terms of
ampere-seconds and ampere-hours in Table 2-1.
2-4
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TABLE 2-1. TOTAL CURRENT SUPPLIED TO TANK DURING SOURCE TESTS
Total current,
Total current, ampere-seconds ampere-hours
Test No. Inlet Outlet Inlet Outlet
90,000,000 83,900,000 25,000 23,300
79,590,000 73,740,000 22,100 20,500
94,620,000 84,350,000 26,300 23,400
2-5
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3.0 SUMMARY OF RESULTS
Particulate matter (EPA Method 5) tests were conducted at the inlet and the
outlet of the packed-bed wet scrubber controlling the decorative chrcmiun
plating tank. Because the emissions were chromic acid fumes, "impinger train"
tests were run at the scrubber inlet to evaluate the use of Method 5 for sample
collection. An additional run using the Method 5 train was conducted at a high
sampling rate (HV) for eight hours at a single point. The data is presented
for the high volume run but not discussed since the other tests were
quantifiable and conducted isokinetically at all points. Table 3.1 summarizes
the testing schedule for this testing program.
In brief, from the results of the Method 5 testing, the uncontrolled
emissions from the tank averaged 0.035 pounds per hour of particulate matter,
0.000017 pounds per hour of hexavalent chromium, and 0.000065 pounds per hour
of total chromium. Based on the Method 5 results, the controlled emissions
averaged 0.024 pounds per hour of particulate matter, 0.000016 pounds per hour
of hexavalent chrcmiun, and 0.000095 pounds per hour of total chromium. Also
based on the Method 5 results, the collection efficiency of the wet scrubber
appeared to be low, however, this is inconclusive due to questionable data
quality as indicated by the methods evaluation comparison with the impinger
train. The impinger train samples were not analyzed for particulate matter.
The collection efficiency of the impinger train indicated that essentially all
the chromium was collected by the impingers and the impinger train results for
hexavalent chromium at 0.00011 pounds per hour averaged about seven times
greater than those from the Method 5 train.
3-1
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TABLE 3.1. TESTING SCHEDULE FOR C. S. OHM
Date
(1985)
6A8
6/19
6/20
Sample Type
Participate
Participate
Participate (HV)**
P articulate
Scr
Run
No.
2
5
SR
8
Libber Inlet
Test Time
24 h clock
1004-1529
0838-1404
1419-2247
0855-1420
Scrubber Inlet
(Implnger Train)*
Run
No.
1
4
7
Test Time
24 h clock
1005-1530
0839-1405
0856-1421
Scrubber Outlet
Run
No.
3
6
9
Test Time
24 h clock
1003-1505
0837-1336
0855-1350
U)
I
*Runs 1, 4, and 7 utilized an Implnger train.
**Spec1al high volume, constant rate, single point, run (SR).
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In the following sections, the results addressed above and additional
results are presented and discussed in detail according to the emission type
and sampling location. The computer printouts of the emission calculations
can be found in Appendix A. The original field data sheets and the analytical
data are located in Appendix B.
3.1 PAKTICULATE MATTER, HEXAVALENT CHROMIUM, AND TOTAL CHROMIUM
Particulate matter tests (EPA Method 5) along with the determination of the
associated flue gas flow rates were conducted at both the scrubber inlet and
outlet; impinger train method evaluation tests were conducted at the scrubber
inlet. The particulate matter samples were initally analyzed using gravi-
metric techniques to determine the mass of particulate matter. Then the
samples were further analyzed for hexavalent and total chrcmiun. The impinger
train samples were analyzed for hexavalent and total chromium only. Complete
descriptions of each sampling location and the sampling and analytical
procedures are given in Chapter 4 (and Appendix C).
3.1.1 Scrubber Inlet (EPA Method 5)
The results for the scrubber inlet (EPA Method 5) represent the
uncontrolled emissions from the plating tank as measured by EPA Method 5. The
circular vertical inlet duct was traversed with both an EPA Method 5 sampling
train and an impinger train. The results from these two trains should be
compared for methods evaluation purposes as a check on the ability of the EPA
Method 5 sample train to collect chromic acid fines.
Flue Gas Conditions and Isokinetic Sampling Rate - A sunmary of the flue
gas conditions at the scrubber inlet (EPA Method 5 and impinger train) and the
scrubber outlet (EPA Method 5 train) is presented in Table 3.2. The volunetric
3-3
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TABLE 3.2. SIM WRY OF FLUE GAS CONDITIONS
Run
No.
Date
(1985)
Test Time
24 h clock
Volumetric Flow Rate
Actual8
acmh
x 106
acfh
x 106
Standard"
dscmh
xlO6
dscfh
x 106
Stack
Temperature
°C
°F
Malsture
°2
co2
CO
Isoklnetlc
Scrubber Inlet (Implnger Train)
1
4
7
6/18
6/19
6/20
1005-1530
0839-1 405
0856-1421
Average
0.0216
0.0215
0.0216
0.0216
0.764
0.759
0.764
0.762
0.0203
0.0204
0.0204
0.0204
0.717
0.719
0.719
0.718
25
24
26
25
77
76
79
77
1.0
1.0
1.0
1.0
20.9
20.9
20.9
20.9
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
98.7
98.6
98.4
Scrubber Inlet (Method 5)
2
5
8
6/18
6/19
6/20
1004-1529
0838-1404
0855-1420
Average
0.0206
0. 0200
0.0212
0.0206
0.728
0.705
0.748
0.727
0.0194
0.0188
0.0199
0.0194
0.685
0.664
0.703
0.684
25
25
26
25
77
77
79
78
0.8
1.3
1.2
1.1
20.9
20.9
20.9
20.9
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
97.6
100.6
99.2
Scrubber Inlet - Special Run
SR
6/19
1419-2247
0.0197
0.695
0.0187
0.660
26
79
0.2
20.9
0.0
0.0
79.8
Scrubber Outlet
3
6
9
6/18
6/19
6/20
1003-1505
0837-1336
0855-1 350
Average
0.0222
0.0221
0.0222
0.0222
0.785
0.780
0.783
0.783
0.0212
0.0211
0.0211
0.0211
0.749
0.747
0.744
0.747
20
20
22
21
68
68
72
69
1.4
1.7
1.8
1.6
20.9
20.9
20.9
20.9
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
94.2
94.6
94.5
Volumetric flow rate In actual cubic meters per hour (acmh) and actual cubic feet per hour (acfh) at stack conditions.
Volumetric flow rate In dry standard cubic meters per hour (dscmh) and dry standard cubic feet per hour (dscfh).
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flow rates for the inlet Method 5 tests were fairly consistent and averaged
20,600 actual cubic meters per hour (727,000 actual cubic feet per hour).
The flue gas temperature averaged 25°C (78°F), with a moisture content
of 1.1 percent. The oxygen, carbon dioxide, and carbon monoxide content was
that of air at 20.9, 0.0, and 0.0 percent, respectively. The volunetric flow
rate at standard conditions averaged 19,400 dry standard cubic meters per hour
(684,000 dry standard cubic feet per hour). Standard conditions are 20°C
(68°F), 760 mm Hg (29.92 in. Hg), and dry. The isokinetic sampling rate was
within the allowable range for all three sample runs.
Particulate Emissions - The particulate emissions from the plating tank
(see Table 3.3) were variable. The particulate emissions for the inlet runs
averaged 0.82 milligrams per dry standard cubic meter (0.00036 grains per dry
standard cubic foot) and 0.016 kilograms per hour (0.035 pounds per hour). The
variability was likely due to sampling and analytical error in measuring the
extremely low pollutant concentrations.
Hexavalent Chromium Emissions - The hexavalent chromium emissions for each
test run (see Table 3.3) were also variable with the corresponding particulate
run. They averaged 95, 2150, and 633 milligrams of hexavalent chromiuu per
gram of particulate emissions for runs 2, 5, and 8, respectively. The
hexavalent chromium emissions for the inlet tests averaged J3.39 x 10
milligrams per dry standard cubic meter (0.17 x 10~ grains per dry standard
cubic foot) and 7 x 10 kilograms per hour (17 x 10 pounds per hour).
Total Chromium Emissions - The total chromiuu emissions for each test run
(see Table 3.3) were variable with respect to the corresponding particulate run
and averaged 423, 8290, and 2429 milligrams of total chromium per gram of
3-5
-------
TABLE 3.3. SUMMARY OF PARTICULATE, HEXAVALENT CHROMIUM, AND TOTAL OROMIUM EMISSIONS
Run
No.
Date
(1985)
Partlcul ate
concentration
mg/dscm
gr/dscf
mass emissions
kg/h
Ib/h
Hex av a lent Chromium
concentration
mg/dscm
x 10~3
gr/dscf
x 10~3
mass emissions
kg/h
x 10"-5
Ib/h
x 10~3
Total Chromium
concentration
mg/dscm
x JO"3
gr/dscf
x IO"3
mass emissions
kg/h
x IO"3
Ib/h
x 10~3
Scrubber Inlet (Implnger Train)
1
4
7
6/18
6/19
6/20
Average
(not anal
/zed)
2.35
2.02
3.14
2.50
0.00103
0. 00088
0.00137
0.00109
0.048
0.041
0.064
0.051
0.10
0.09
0.14
0.11
12.13
6.83
13.40
10.8
0.0053
0.0030
0.0059
0.0047
0.246
0.139
0.273
0.22
0.543
0.306
0.602
0.48
Scrubber Inlet (Method 5)
2
5
8
6/18
6/19
6/20
en
Average
1.27
0.20
0.98
0.82
0.00056
0. 00009
0. 00043
0.00036
0.025
0.004
0.020
0.016
0.054
0.008
0.043
0.035
0.12
0.43
0.62
0.39
0. 00005
0.00019
0.00027
0.00017
0.002
0.008
0.012
0.007
0.005
0.018
0.027
0.017
0.537
1.658
2.380
1.52
0. 00023
0.00072
0.00104
0.0007
0.010
0.031
0.047
0.029
0. 023
0.069
0.104
0.065
Scrubber Inlet (Special Run)
SR
6/19
0.226
0.00010
0.004
0.009
0.36
0.00016
0.007
0.015
0.91
0. 0004
0.017
0.038
SR
6/19
0.226
0.00010
0.004
0.009
0.36
0.00016
0.007
0.015
0.91
0. 0004
0.017
0.038
Scrubber Outlet
3
6
9
6/18
6/19
6/20
Average
*
0.524
»
0.524
*
0.00023
*
0.00023
*
0.011
*
0.011
»
0.024
»
0.024
0.27
0.34
0.41
0.34
0.00012
0.00015
0.00018
0.00015
0.006
0.007
0.009
0.007
0.013
0.016
0.019
0.016
2.406
1.826
1.899
2.04
0.00105
0.00080
0.00083
0. 0009
0.051
0.039
0.040
0.043
0.112
0.085
0.088
0.095
*Partlculate catch was not quantifiable.
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particulate. The total chromium emissions averaged 1.52 x 10 milligrams
per dry standard cubic meter (0.7 x 10 grams per dry standard cubic foot)
and 0.029 x 10 kilograms per hour (0.065 x 10 pounds per hour).
3.1.2 Scrubber Inlet (Impinger Train)
The results for the scrubber inlet (impinger train) represent the
uncontrolled emissions from the plating tank as measured by the impinger
train. The Method 5 and impinger train sampling were conducted simultaneously
in the vertical circular duct prior to the packed bed scrubber. The impinger
train tests wree conducted to evaluate the use of the Method 5 train for the
reference method collection of the chromic acid fumes for the chromium plating
industry. The results of the Method 5 and impinger train testing should be
comparable.
Flue Gas Conditions and Isokinetic Sampling Rate - A summary of the flue
gas conditions at the scrubber inlet (impinger train) is presented in
Table 3.2. The volumetric flow rate results for both the Method 5 train and
impinger train were within standard measurement error of each other. The
isokinetic sampling rate was within the allowable range for all three impinger
train sample runs.
Particulate Emissions - The collected samples were not analyzed for
particulate emissions since all of the impinger contents would have had to be
taken to dryness. Also, it would have made the analysis for hexavalent and
total chromium more difficult in the sample preparation phase.
Hexavalent Chromium Emissions - The hexavalent chromium emissions were
fairly consistent averaging 2.5 x 10 milligrams per dry standard cubic
6 6
meter (1.1 x 10 grains per dry standard cubic foot) and 51 x 10
kilograms per hour (110 x 10 pounds per hour). This was about seven times
greater than the hexavalent chromium emissions measured by the EPA Method 5
train. The reason for the extremely poor agreement is not known.
3-7
-------
Total Chromium Emissions - The total chromium emissions averaged 10.8 x
10~ milligrams per dry standard cubic meter (4.7 x 10 grains per dry
standard cubic foot) and 0.22 x 10~ kilograms per hour (0.48 x 10 pounds
per hour). This was about eight times greater than the total chromium
emissions measured by the EPA Method 5 train. This is in agreement with the
comparison of the hexavalent chromium results between the two sampling trains.
3.1.3 Scrubber Outlet
The scrubber outlet represents the controlled emissions from the chrcmiun
plating tank as measured by EPA Method 5? no impinger train tests were
conducted at the scrubber outlet. A four-inch filter and larger than normal
size nozzle were used in an effort to collect the maximun sample volvme under
isokinetic sampling conditions.
Flue Gas Conditions and Isokinetic Sampling Rate - A sunmary of flue gas
conditions at the scrubber outlet is presented in Table 3.2. The volunetric
flow rates for the three outlet runs were very consistent. The outlet
volunetric flow rate averaged 22,200 actual cubic meters per hour (783,000
actual cubic feet per hour) with a flue gas temperature of 21°C (69°F) and
a moisture content of 1.6 percent. The oxygen, carbon dioxide, and carbon
monoxide concentrations were that of ambient air at 20.9, 0.0, and 0.0 percent,
respectively. The volunetric flow rate at standard conditions averaged 21,100
dry standard cubic meters per hour (747,000 dry standard cubic feet per hour).
Standard conditions are 20°C (68°F), 760 mm Hg (29.92 in. Hg), and dry.
The isokinetic sampling rates were well within the allowable range for all
runs.
Particulate Emissions - The particulate emissions exiting from the control
equipment to the atmosphere were not quantifiable (see Table 3.3) for two of
the three runs. For the one run which had quantifiable results, the particulate
3-8
-------
emissions averaged 0.5 milligrams per dry standard cubic meter (0.0002 grains
per dry standard cubic foot) and 0.01 kilograms per hour (0.02 pounds per
hour). The other two runs had negative sample weights. Method 5 was intended
to accurately measure pollutant concentrations at these low levels.
Hexavalent Chromium Emissions - The hexavalent chromium emissions for each
test run were fairly consistent and averaged 0.34 x 10"^ milligrams per dry
standard cubic meter (0.15 x 10" grains per dry standard cubic feet) and
7x10 kilograms per hour (16 x 10 pounds per hour). These results
were similar in magnitude to the Method 5 uncontrolled results.
Total Chromium Emissions - The total chromium emissions were fairly
consistent and averaged 2.04 x 10~3 milligrams per dry standard cubic meter
(0.9 x 10~5 grams per dry standard cubic foot) and 0.043 x 10~ kilograms
per hour (0.095 x 10" pounds per hour). These results were greater than the
controlled emissions as measured by the EPA Method 5 train.
3.2 EMISSIONS IN UNITS OF PROCESS RATE AND CONTROL EQUIPMENT COLLECTION
EFFICIENCY
The emission rates in units of process rate are given in terms of
milligrams of emissions per hour per square foot of tank surface area, and in
units of milligrams of emissions per amperage input to the plating operation.
To determine the collection efficiency of the scrubber, the milligrams per hour
per square foot (uncontrolled emissions and controlled emissions) were used for
the calculations.
3.2.1 Emissions in Units of Process Rate
Two process parameters were used to determine the emissions in terms of
units of the process rate as shown in Table 3.4. The first was milligrams of
emissions per amperage input to the plating operation. The second was
milligrams of emissions per hour per square foot of tank surface area. The
surface area of the tank was 45 ft for all tests.
3-9
-------
TABLE 3.4. SUMMARY OF EMISSION RATES IN UNITS OF PROCESS RATE AND EFFICIENCY
Run
Nos.
Process Rate
current sup-
pi led to tank
1 n amps/hr
Uncontrolled Emissions
part leu 1 ate
ing/amp
mg/hr
ft2
hexavalent
chromium
mg/amp
mg/hr
ft2
total
chromium
mg/amp
mg/hr
ft2
Controlled Emissions
partlcul ate
mg/amp
mg/hr
ft2
hexavalent
chromium
mg/amp
mg/hr
ft2
total
chromium
mg/amp
mg/hr
ft2
Collection Efficiency**
part icul ate
%
hexavalent
chromium
%
total
chromium
%
Scrubber Inlet (Implnger Train)
1
4
7
25,000
22.100
26,300
Average
not
analyzed
not
analyzed
0.0019
0.0019
0.0024
0.0021
1.07
0.91
1.42
1.13
0.0098
0. 0063
0.0104
0. 0088
5.46
3.09
6.07
4.87
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
Scrubber Inlet (Method 5)
D
2
5
8
25,000
22,100
26,300
Average
0.0010
0.0002
0.0008
0.0007
556
89
444
363
0. 00008
0. 00036
0.00046
0. 00030
0.04
0.18
0.27
0.16
0.0004
0.0014
0.0018
0.0012
0.22
0.69
1.04
0.65
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
Scrubber Outlet (Method 5)
3
6
9
23,300
20, 500
23,400
Average
N/A
N/A
N/A
N/A
N/A
N/A
no val
0.00054
no val
0.00054
no val
244
no val
244
0.00026
0.00034
0.00038
0.00033
0.13
0.16
0.20
0.16
0.0022
0.0019
0.0017
0.0019
1.13
0.87
0.89
0.96
no val
no val
32.8***
11.1
25.9
0***
14.4
»**
Emission rate In units of milligrams of emissions per hour per square foot of tank surface using a tank surface of 45 ft for all tests.
**Alr pollution control efficiency calculations are based on uncontrolled and controlled emissions In units of mg/hr/ft .
Calculated based on averages of uncontrolled and controlled emissions.
-------
3.2.2 Control Equipment Collection Efficiency
The collection efficiency of the packed-bed scrubber (see Table 3.4) was
extremely low based on the EPA Method 5 results. The control equipnent
collection efficiency was 32.8 percent for particulate and was zero percent for
hexavalent chromium. The measured emissions for total chrcmiun were greater
after the scrubber than prior to the scrubber. The validity of the results are
questionable based on the methods evaluation tests and should not be used as an
accurate indication of collection efficiency.
3.3 SUMMARY OF ANALYTICAL RESULTS FOR HEXATALENT AND TOTAL CHROMIUM
The summary of analytical results for the hexavalent chromium and total
chromium analyses of samples collected is presented in Table 3.5. The
analytical data sheets are contained in Appendix B. The results shown in Table
3.5 for hexavalent and total chromium are the results obtained using the EPA
tentative method for "Determination of Hexavalent Chromium Emissions from
Stationary Sources" and the "EPA Protocol for Emissions Sampling for Both
Hexavalent and Total Chromium" (see Appendix C). When, for total chrcmiun
analysis, the table indicates that the sample "residue" was analyzed, then the
values presented for total chrcmiun content are a sun of (1) the hexavalent
chromium in the sample filtrate from the extraction of the sample and (2) the
chromium in the residue from the extraction as measured by Neutron Activation
Analysis. When the table indicates that the "total" sample was analyzed, then
the values presented for total chromium content are from the direct analysis of
the total sample for total chromium by Neutron Activation Analysis. A table
showing the total chromium calculations for each sample can be found at the end
of Appendix A of this report.
The collection efficiency of hexavalent chromium by the impinger train is
believed to be greater than 99%. The efficiency was determined by analyzing
the impinger contents separately as shown in Table 3.5.
3-11
-------
TABLE 3.5 SUMM/RY OF ANALYTICAL RESULTS FCR HEXAVALENT AND TOTAL CWOMIUM
Run
No.
Sample
Type
Sample
No.
Analyzed
Amount of
Samp 1 e
Analyzed
Hexavalent Chromium
Results
yg
Concentration
pg/g
Amount of
Samp 1 e
Analyzed
Total Chromium
Results
yg
Concentration
yg/g or yg/ml
Scrubber Inlet (Implnger Train)
I
1
1
4
4
4
7
7
7
1st Implnger Contents
2nd Implnger Contents
3rd Implnger Contents
1st Implnger Contents
2nd Implnger Contents
3rd Implnger Contents
1st Implnger Contents
2nd Implnger Contents
3rd Implnger Contents
C-255
C-256
C-257
C-258
C-259
C-260
C-261
C-262
C-263
Total
Total
Total
Total
Total
Total
Total
Total
Total
15.6
< 0.2
< 0.2
13.2
< 0.2
0.2
19.4
0.7
0.7
.(.
15.6 yg total
.)
13.4 yg total
4.
20.8 yg total
Half
Half
Half
Half
Half
Half
Half
Half
Half
77.38*]
2.56»>
2.26*)
71.70*]
8.84* J
10.36*)
t
80.5 yg total
f
45.4 yg total
t
88.9 yg total
Scrubber Inlet (Method 5 and High Volume Train)
2
2
5
5
8
8
SR
SR
Part leu late Front Half
Implnger Contents
Part leu late Front Half
Implnger Contents
Part leu late Front Half
Implnger Contents
Partlculate Front Half
Implnger Contents
C-241
C-249
C-242
C-250
C-243
C-251
C-244
C-267
8.3 mg
Total
1 .3 mg
Total
6. 7 mg
Total
3.7 mg
Total
0.8
< 0.2
2.8
< 0.2
4.2
< 0.2
5.9
< 0.2
96
negl Iglble
2150
neg 1 Iglble
627
neg 1 1 g I b 1 e
1590
negl Iglble
Residue
Half
Residue
Half
Residue
Half
Residue
Half
2.5
1.0
9.4
1.4
16.2
14.9
301.2
7230.8
2417.9
4027.0
__*._
Scrubber Outlet
3
3
6
6
9
9
Partlculate Front Half
Implnger Contents
Part I cu late Front Half
Implnger Contents
Partlculate Front Half
Implnger Contents
C-245
C-252
C-246
C-253
C-247
C-254
»*
Total
4. 1 mg
Total
**
Total
2.1
< 0.2
2.7
< 0.2
3.2
< 0.2
*»
neg 1 Iglble
659
negl Iglble
**
neg 1 Iglble
Residue
Half
Residue
Half
Residue
Half
18.8
14.3
14.8
*_
3487.8
Scrubber Water Discharge (liquids)
Scrubber H,0
C-265
~
5.09 yg/ml
1.0 ml
12.7
12.7 y g/ml
Blank Samples
Partlculate Fl Iter
Distilled H20 w/Acetone
C-248
C-264
1.1
< 0.2 yg/ml
Residue
1.0 ml
6.7
2.0
2.0 yg/ml
*Not blank corrected. **Partlculate catch was not quantifiable.
The concentration In terms of yg/g could not be calculated since the mass collected by the Implngers was not determined; the value represents
the total weight of chromium collected In all three Implngers.
-------
Both the quantity of the particulate and the hexavalent chromium analyzed
were extremely low and, under these circumstances, both sets of analytical
results are subject to greater analytical error.
Quality assurance audit samples were analyzed for both the hexavalent and
total chromium methods. As shown in Table 3.6, no bias was present and the
results are considered acceptable.
There is some sample analysis variability due to the small amount of
hexavalent chromium present. However, the average values for the runs are
believed to be fairly accurate.
3-13
-------
TABLE 3.6. SUMM/WY OF ANALYTICAL RESULTS FCR HEXAVALENT AND TOTAL OROMIUM QUALITY ASSLRANCE SAffLES
Run
No.
Sample
Type
Sample
No.
True
Value
Hexavalent Chromium
Results
Ug/ml
%
Dev.
Total Chromium
Results
P9
%
Dev.
Quality Assurance Samples
--
Qual Ity Assurance
Qual Ity Assurance
Qual Ity Assurance
Qual Ity Assurance
C-266
OA-16
OA-17
QA-18
50 ug/ml Cr*6
50 ug Cr
100 ug Cr
150 yg Cr
52.4
+4.8
45.69
96.49
146.4
-8.6
-3.5
-2.4
-------
4.0 SAMPLING LOCATIONS AND TEST METHODS
This section describes the sampling locations and test methods used to
characterize emissions from the decorative chromium plating tank at C. S. Ohm
Manufacturing Company in Sterling, Michigan. Two sampling locations were used
in the emission testing program. At each sampling location (one at the
scrubber inlet and one at the scrubber outlet), emissions testing was conducted
for participate matter, total chromium content, and hexavalent chrcmiun
content. Sampling for chrcmiun and an impinger collection efficiency
determination was also conducted at the scrubber inlet using an impinger
train. One special high volune, constant flow rate, single point sampling run
was conducted at the inlet, also. The relative positions and the type of
testing conducted at each location are shown in the simplified process flow
diagram (see Figure 4-1) and accompanying Table 4.1. The subsections which
follow further describe each sampling location and applicable test methods.
4.1 SCRUBBER INLET (SAMPLING LOCATION A)
Particulate matter, hexavalent chromiun, and total chrcmiun were measured
at the inlet to the packed-bed scrubber controlling emissions from the
decorative chromiun plating tank as shown in Figure 4-2. Two sampling ports
were installed 90° apart in the vertical circular duct (32 inches in
diameter). These ports were located 26 inches (0.81 duct diameters) upstream
of a bend in the duct to the scrubber and 168 inches (5.25 duct diameters)
downstream from another bend.
4-1
-------
16,000 SCFM
TO ATMOSPHERE
VIRON
WET
BED
SCRUBBING
LIQUID
HOLDING
TANK
/ x' X x< //
32-IN. DIAMETER
RIGID PVC DUCT
PUSH-PULL
VENTILATION
X- "" '
-«<
Ni
PLATINC
RINSE
RINSE
. «.
|
i - i
DILUTE
Cr03
. »
CK)/
PLATING
RINSE
^»v
Figure 4-1.Diagram of decorative chromium plating line and emissions
control system at C. S. Ohm Manufacturing Company.
4-2
-------
TABLE 4.1. SAMPLING PLAN FOR C. S. QW
Sample Type
Sampl ing
Locations
Number
of Samples
Methods
Particulate matter
Hexavalent chromium
Total chromium
Chromium (Impinger
efficiency)
A, B
A, B
A, B
3 (M5)
1 (M5 HV. at A)
3 (M5)
1 (M5 HV, at A)
3 (M5)
1 (M5 HV, at A)
EPA Method 5 or
EPA Method 5 High Volume
EPA Method 5 or
EPA Method 5 High Volume
using Tentative EPA
Method for Hexavalent Chromium
EPA Method 5 or
EPA Method 5 High Volume
using EPA Protocol for
Total Chromium
Impinger Train using
Tentative EPA Method for
Hexavalent Chromium and EPA
Protocol for Total Chromium
4-3
-------
TRAVERSE POINTS
2 AXES
8 POINTS/AX IS
16 TOTAL POINTS
32"DIA.
SECTION L-L
TO
SCRUBBER
ROOF LINE ]8]
f
B
26"
t
168"
FROM
PROCESS
ELEVATION VIEW
FIGURE 4-2. SCRUBBER INLET (SAMPLING LOCATION A)
4-4
-------
For the Method 5 testing, (used for particulate matter, hexavalent
chromiun, and total chromiun determinations) and the impinger train testing, a
total of 16 points, as per Method 1, were sampled. Each of the 16 points was
sampled for 20 minutes for a total of 320 minutes of sampling per run. Each of
three Method 5 and three impinger train runs were conducted to coincide with
the sampling at the scrubber outlet location.
4.2 SCRUBBER OUTLET STACK (SAMPLING LOCATION B)
Particulate matter, hexavalent chromiun, and total chromium were measured
at the scrubber outlet as shown in Figure 4-3. Four sampling ports were
installed along the shorter side of the 26 1/2 by 34 3/4 inch vertical
rectangular stack. The ports were located about 8 inches (0.025duct diameters)
upstream from the stack exit and 32 1/4 inches (1.07 duct diameters) downstream
from the fan. Because of the close proximity of the flow disturbance (stack
exit) downstream of the ports, this location did not meet EPA Method 1 sampling
requirements; a planned stack extension was refused by EPA for reasons of
excessive additional cost.
For the EPA Method 5 sampling (used for particulate matter, hexavalent
chroraiua, and total chromiun determinations), a total of 24 points, 6 per axis,
were sampled. Each point was sampled for 12 minutes for a total sampling time
of 288 minutes.
4.3 VELOCITY AND GAS TEMPERATURE
A type S pitot tube and an inclined draft gauge manometer or two
differential pressure gauges in-parallel were used to measure the gas velocity
pressure ( p). Velocity pressures were measured at each sampling point across
4-5
-------
34.75"
< 26.5" >
. i
1
i
i
1
i
-I
i
- - -i
. i
1
i
i
A
. i
i
i
~ ~ r
i
r-
i
u
. i
_ L
I
I
B
SECTION
. t
1
i
i
~T
1
- I-
1
--!
. 1
_ J.
1
1
c
R-
. -
*
-
_ _
,
D
R
TRAVERSE POINTS
4 AXES
6 POINTS/AX IS
24 TOTAL POINTS
k-26.5"
1
k 34.75">j
3"
[
.25"
t
k
6"
A B C D
t
I.D.
FAN
R
FROM Z
SCRUBBER ,
FIGURE 4-3. SCRUBBER OUTLET (SAMPLING LOCATION B)
4-6
-------
the duct to deteimine an average value according to the procedures outlined in
Method 2 of the Federal Register.* The temperature at each sampling point was
measured using a thermocouple and digital readout.
4.4 MOLECULAR WEIGHT
Flue gas composition was essentially that of the ambient air drawn in from
above the plating tank. Therefore, the dry molecular weight and composition of
air was used.
4.5 PAKTICULATE MATTER
Method 5, as described in the Federal Register,* was used to measure
particulate grain loading at locations A and B. All tests (except the special
high voluue run) were conducted isokinetically by traversing the
cross-sectional area of the stack and regulating the sample flow rate relative
to the flue gas flow rate as measured by the pitot tube attached to the sample
probe. A sampling train consisting of a heated, glass-lined probe, 79 mm
(3 inch) [or 102 mm (4 inch) for the high volune run] diameter Teflon filter
(Schleicher & Schuell), and a series of Greenburg-Smith impingers was employed
for each test. An acetone rinse and a water rinse of the nozzle, probe, and
filter holder portions of the sample train were made at the end of each test.
The particulate caught on the filter media was dried at room temperature, the
combined acetone and water rinse was taken to dryness in an oven; both were
desiccated to a constant weight, and weighed on an analytical balance. Total
filterable particulate matter was determined by adding these three values. See
Appendix C for detailed sampling procedures.
4-7
-------
4.6 IMPINGER COLLECTION EFFICIENCY
A sample train similar to that used for EPA Methods 1-5 was used to measure
the impinger collection efficiency at the scrubber inlet. The train did not
contain any filter, instead a filter bypass was inserted in the line and three
Greenburg-Smith impingers each containing 100 ml of distilled water were used
to collect the emissions. The impinger train tests were run simultaneously
with the Method 5 tests and were conducted isokinetically by traversing the
cross-sectional area of the stack and regulating the sample flow rate relative
to the flue gas flow rate as measured by the pitot tube attached to the sample
probe. The contents of each impinger were recovered separately at the end of
each test. Each impinger was rinsed first with acetone and then with water;
these rinses were then added to the corresponding impinger contents. The probe
and filter bypass were also rinsed with both acetone and water and these rinses
were added to the first impinger contents. The contents and rinses from each
impinger were concentrated and analyzed for hexavalent and total chromiun
content.
4.7 HEXAVALENT CHROMIUM CONTENT
Hexavalent chromium content was determined utilizing procedures described
in the tentative EPA Method "Determination of Hexavalent Chromium Emissions
from Stationary Sources" (see Appendix C). The Method 5 filter catches
collected and weighed for each Method 5 run and the. impinger train impinger
catches were taken and analyzed for hexavalent chroraiun content using this
method. It was also used to determine the hexavalent chromiun content in the
first impinger for representative Method 5 runs.
* 40 CFR 60, Appendix A, Reference Methods 2, 3, and 5, July 1, 1980.
4-8
-------
4.8 TOTAL CHROMIUM CONTENT
Total chromium content was determined using procedures described in the
"EMB Prototcol for Sample Preparation and Emission Calculation of Field Samples
for Total Chromium" in combination with Neutron Activation Analysis (NAA) (see
Appendix C). Samples collected during Method 5 and impinger train runs and
first submitted for analysis for hexavalent chromiun were then analyzed for
total chromiun using this method.
4-9
-------
5.0 QUALITY ASSURANCE
Because the end product of testing is to produce representative emission
results, quality assurance is one of the main facets of stack sampling.
Quality assurance guidelines provide the detailed procedures and actions
necessary for defining and producing acceptable data. Two such docunents were
used in this test program to ensure the collection of acceptable data and to
provide a definition of unacceptable data. These docunents are: the EPA
Quality Assurance Handbook Volune III, EPA-600/4-77-027 and Entropy's "Quality
Assurance Program Plan" which has been approved by the U. S. EPA, EMB.
Relative to this test program, the following steps were taken to ensure
that the testing and analytical procedures produce quality data.
Calibration of field sampling equipment. (Appendix D describes
calibration guidelines in more detail.)
Checks of train configuration and on calculations.
On-site quality assurance checks such as sampling train, pitot
tube, and Orsat line leak checks, and quality assurance checks of
all test equipment prior to use.
Use of designated analytical equipment and sampling reagents.
Table 5-1 summarizes the on-site audit data sheets for the sampling
equipment used for particulate testing at each sampling location, including
deviation limits. In addition to the pre- and post-test calibration audits, a
field audit was performed on the meter boxes used for sampling. Entropy used
the procedures described in the December 14, 1983 Federal Register (48FR55670).
In addition, the analytical balance used for filter weighing was audited with
Class "S" weights. Appendix D includes the audit run data sheets for each dry
gas meter used for particulate testing and audit data sheets for the other
sampling equipment.
5-1
-------
TABLE 5.1. FIELD EQUIPMENT CALIBRATION
Equipment
Reference
Al lowable
Error
Actual
Error
Within
Al lowable
Limits
Scrubber Inlet
Meter box (N-5)
Meter box thermometer
Trip balance
Analytical balance
Wet test meter
ASTM-3F at ambient
temperature
IOLM standard weight
Cl ass "S" standard
weight
Y + 0.03Y
5°F
0.5 grams
0.1 mg
-KK025
+1«F
0.1 gram
0.02 mg
v^
Y
-]/
-------
Audit solutions prepared by the EPA were used to check the analytical
procedures of the laboratories conducting the hexavalent and total chromium
analyses. Table 5-2 presents the results of these analytical audits. The
audit tests show that the analytical techniques were good.
The sampling equipment, reagents, and analytical procedures for this test
series were in compliance with all necessary guidelines set forth for accurate
test results as described in Volune III of the Quality Assurance Handbook.
5-3
-------
TABLE 5.2. AUDIT REPORT CHROMIUM ANALYSIS
Plant
: C-S.
Task No.: 3£>Z-
Date sample:
Sample anal;
Reviewed by
Sample
Number
O266
QA-U,
QA-I7-
GJA-/S
3 received: //
fzed by: fC_<
'Tc^c^ £"^
ug/ml
Cr*6 or Cr
£OW/*L
si ^ ^^
/^/i^ ^*"
i /
2- / 6 5~~ Dat
r
lS«- Dat
Source of
Sample
Q4D
A/£^
tf6s
rt&$
:e analyzed: //
/
:e of review:
Audit
Value
57?. 4-
-^r.6f
f^.f^
/^.f
files'
Relative
error, %
^^.6^
-3-C- %
-3,5-^0
- ^.f %
5-4
------- |