United States Office of Air Quality EPA-450/3-82-008
Environmental Protection Planning and Standards February 1982
Agency Research Triangle Park NC 27711
Air
Revisions to Methods
101,101A, and 102
for Determination
of Mercury Emissions
Summary of Comments
and Responses
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EPA-450/3-82-008
Revisions to
Methods 101. 101A, and 102 for
Determination of Mercury Emissions
(Proposed October 15, 1980,45 FR 68514)
Summary of Comments and Responses
Emission Standards and Engineering Division
U.S. ENVIRONMENTAL PROTECTION AGENCY
Office of Air, Noise, and Radiation
Office of Air Quality Planning and Standards
Research Triangle Park, North Carolina 27711
February 1982
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This report has been reviewed by the Emission Standards and Engineering Division of the Off ice of Air Quality Planning
and Standards, EPA, and approved for publication. Mention of trade names or commercial products is not intended tc
constitute endorsement or recommendation for use. Copies of this report are available through the Library Service
Office (MD-35), U. S. Environmental Protection Agency, Research Triangle Park, N. C. 27711, orfrom National Technics
Information Services, 5285 Port Royal Road, Springfield, Virginia 22161.
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TABLE OF CONTENTS
Page
Chapter 1. INTRODUCTION 1
Chapter 2. SUMMARY OF CHANGES SINCE PROPOSAL
Chapter 3. SUMMARY OF PUBLIC COMMENTS AND RESPONSES. . 4
Table 1. LIST OF COMMENTERS 16
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CHAPTER 1
INTRODUCTION
On October 15, 1980, the U. S. Environmental Protection
Agency published in the Federal Register (45 FR 68514) revisions
to Methods 101 and 102, "Determination of Particulate and
Gaseous Mercury Emissions from Chior-Alkali Plants - Air Streams,"
and "Determination of Particulate and Gaseous Mercury Emissions
from Chlor-Alkali Plants - Hydrogen Streams," respectively, and
a new Method 111, "Determination of Particulate and Gaseous Mercury
Emissions from Sewage Sludge Incinerators." Method 111 has been
redesignated as Method 101A. These revised methods and new method
were proposed under the authority of Sections 112, 114, and 301(a)
of the Clean Air Act, as amended.
Public comments were solicited at the time of proposal. To
provide interested persons the opportunity for oral presentation
of data, views, or arguments concerning the proposed revisions and
test methods, a public hearing was scheduled for November 6, 1980,
at the Research Triangle Park, North Carolina, but no person
desired to make an oral presentation. The public comment period
was from November 6, 1980, to December 15, 1980, and was extended
to February 13, 1981.
Five comment letters were received concerning issues relative
to the proposed test methods. A detailed discussion of these
comments and responses are summarized in this document. The summary
of comments and responses serves as the basis for the revisions which
have been made to the test methods between proposal and promulgation.
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CHAPTER 2
SUMMARY OF CHANGES SINCE PROPOSAL
Method 101
1. Section 4.2. A performance specification has been added
to allow the use of acceptable alternative equipment and procedures.
2. Section 5.3. Criteria for accepting alternative analysis
apparatus are added.
3. Section 5.3.2. Asbestos insulation tape is replaced with
fiberglass insulation tape.
4. Section 5.3.9. Dry, mercury-free air is included as an
option for the aeration gas.
5. Section 6.2.2. It is specified that all mercury standard
solutions be prepared in borosilicate glass containers.
6. Section 7.1.3. The asbestos string gasket used with the
probe nozzle is replaced with a fiberglass string gasket.
7. Section 7.3.2. The first sentence has been reworded to
provide technical clarity.
8. Section 8.3. The option to measure the mercury response by
m
either peak height or peak area is added.
9. Section 9.4. CH ,*„} was corrected to represent total
nanograms of mercury in the aliquot analyzed as opposed to the final
mercury concentration.
Method 101A
1. Section 4. A performance specification has been added to
allow the use of acceptable alternative equipment and procedures.
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2. Section 6.2.5. It is specified that all mercury standard
solutions be prepared in borosilicate glass containers.
3. Section 7.1.1. Two runs are collected to make one sample
where an excess of water condensation is encountered.
4. Section 7.2.1. The first three impingers are included in the
KMnO, rinse for mercury recovery.
5. Section 8.3. The option to measure the mercury response by
either peak height or peak area is added.
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CHAPTER 3
SUMMARY OF PUBLIC COMMENTS AND RESPONSES
Method 101
1. D-2
Comment: Method 101A uses KMnO, as the absorbing medium. We
have extensively and successfully employed KMnO^ to determine Hg
concentrations in gaseous and aqueous streams. We recommend that
KMnO, be specified as an acceptable alternative to IC1 for use in
the collecting liquids for Methods 101 and 102.
Response: IC1 was specified for chlor-alkali plants because the
literature indicates that IC1 is a better oxidizing agent for elemental
Hg and a more stable reagent than KMnO*. Chlor-alkali plants primarily
emit elemental Hg, while sludge incinerators emit Hg compounds. Thus
a strong, fast acting oxidizing reagent is needed for chlor-alkali
plants but not sludge incinerators. However, this does not mean that
KMnO, is unacceptable for chlor-alkali plants. If comparative data
are made available to EPA, consideration will be given to the use of
KMnO* for chlor-alkali plants.
2. D-4
Comment: Paragraph 7.3.2 is confusing. What is the rationale
for pipetting separate flasks? We believe that separate aliquots from
the same flask would be satisfactory. Also, why is it necessary at
all to dilute at this point? This technique would reduce sensitivity
by a factor of 100.
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Response: The first two sentences in the paragraph have been
corrected to read, "Pipet a 2-ml aliquot from the diluted sample
(from Section 7.3.1) into a 250-ml volumetric flask. Add 10 ml of 5 percent
H2SO. and adjust the volume to exactly 250 ml with deionized
distilled water." This dilution step is necessary to reduce the
IC1 concentration to a level that will not inhibit Hg reduction in
the aeration cell and to bring the Hg concentration within the range
of the AA.
3. D-2, D-3, D-4
Comment: Errors in the following sections should be corrected:
a. 5.1.2 Temperature should be 120 instead of 12.
b. 5.1.3 "Lead-free" should be "Leak-free."
c. 5.3.9 Omit the slash between nitrogen and cylinder.
d. 6.2.5 Reference to 7.2.5 should be changed to
7.2.3.
e. 9.4 (1) Use the calibration curve and these corrected
averages, to determine the total weight of
mercury in nanograms in the aeration cell
for each source sample, not concentration.
(2) In Section 9.4, MH should be mH .
(3) Under Eq. 101-1, add: "where: CH (Acj = Total
nanograms of mercury in aliquot analyzed
(reagent blank subtracted)," and change
D.F. = 250/2 if the source samples were diluted
as described in Section 7.3.2, not 7.3.3.
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(4) Eq. 101-2 uses R for emission rate and K
for gas constant. The gas constant is
universally designated R.
^ V Vm(std)> andVw(std) 1nEc>- 101-2 should
be defined.
Response: These corrections have been made. K is not a gas
constant but a numerical/dimensional constant. The terms in item (5)
are defined in Sections 9.1, 9.2, and 9.3.
Method 102
4. D-2
Comment: In 2.3, add the word "mixture" after the word
"explosive."
Response: This suggestion has been incorporated.
Method 101A
5. D-l
/
Comment: The sampling procedure as set forth by Method 101 A, in
general, is viewed as satisfactory.
*
Response: No response needed.
6. D-l
Comment: The change from IC1 to KMnO, is viewed as favorable.
KMnO, can be obtained in purer form than IC1, thus allowing for a
lower Hg concentration in the blank.
Response: No response needed.
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7. D-l
Comment: The use of KMnCL as a rinse of the probe nozzle, probe
fitting, probe liner, and front half of the filter holder would be
quite messy and would tend to increase the mercury in the sample if
the KMnCL is contaminated. Perhaps it would be wise to consider using
8 N HC1 as the rinse since it would be more effective in removing
residual brown deposits and is less messy than KMnCL.
Response: KMnCL is not used in the front half of the train during
sampling, so no brown deposit is formed. The use of KMnCL is preferred
over 8 N HC1 because it is less caustic and can better oxidize and
remove mercury deposits left from the previous sample. The blank would
reveal whether the KMnO^, was contaminated.
8. D-l
Comment: The use of a stainless steel wire screen is highly
recommended as opposed to a glass frit support for the same reason as
stated in the proposed revisions.
Response: No response needed.
9. D-4, D-5
Comment: The use of a stainless steel wire screen ignores the
possibility of loss of mercury through amalgamation or adsorption on
the wire screen.
Response: The use of a filter in this method is optional to
accommodate sources with high particulate loading. At these sources,
essentially all Hg emissions are in the compound form. Glass frits
were found to be a source of cross contamination and are, therefore,
unacceptable.
7-
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Methods 101. 101A, and 102
Analytical Alternatives
10. D-l, D-4, D-5
Comment: The EPA Method 245.1 from Methods for Chemical Analysis
of Water and Wastes (EPA 600/4-79-020) should be incorporated as the
preferred analytical method. This procedure is well documented and
established as producing precise and accurate results. Most
laboratories involved in stack testing will have the equipment and
expertise to routinely perform this analysis.
Response: This method is not equivalent to the Method ,101A
procedure in relation to important dilutions and reagent volumes.
Some deficiencies have been found in the analytical apparatus that
are resolved in Method 101A (discussed in Citation 16 of Method 101).
The need to condition and periodically replace the desiccant, Hg
losses experienced in the BOD bottle, and the technique required to
perform this procedure make it less desirable than Method 101A.
11. D-4, D-5
Comment: Section 5.3.1 specifies a Parkin-Elmer 303 AA or
equivalent. Since the 303 AA is a versatile spectrophotometer, the
phrase "or equivalent" eliminates the possibility of using one of the
commercially available instruments specifically designed for determining
Hg by flameless AA. They are equal to or superior to the 303 for the
analysis of Hg and are much less expensive.
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Response: Substitution of such commercially available systems
is allowable as long as they meet the calibration and analytical
precision and accuracy specified in the method. The following
guidelines will be added to the method.
a. The reducing agent should be added after the aeration cell
is closed.
b. The aeration bottle bubbler should not contain a frit.
c. Any Tygon used should be as short as possible and conditioned
prior to use until blanks and standards yield linear and reproducible
results.
d. If manual stirring is done before aeration, it should be
done with the aeration cell closed.
e. The system must be demonstrated to have accuracy and precision
equivalent to the method (done through replicate analyses of spiked
samples and/or analysis of samples of known concentration obtained from
a reliable source).
f. A drying tube should not be used unless it is conditioned as
the Tygon above.
12. D-2
Comment: Certain other methods than atomic absorption
spectrophotometry for analyzing the absorbing solution are acceptable
alternatives and should be allowed. It is recommended that direct
current argon plasma emission spectrometry (APES) be included in the
test methods as an alternative to atomic absorption. Attached is a
reprint which elaborates on the use of APES.
9-
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Response: Alternative methods are allowed on a case-by-case basis.
In the case of the APES method, the level of operator skill
and equipment needs are much higher than most companies will have
available. It is a sophisticated technique that yields results very
sensitive to operator technique and, therefore, is not readily adaptable
at this time to routine, widespread use.
Variations in Equipment Specifications
13. D-2, D-4, D-5
Comments: (a) Variations in the dimensions of the optical cell
should be allowed because: (1) calibration with a given cell adjusts
for its peculiarities. (2) The dimensions specified do not coincide
with cells in commercially available instruments. (3) The large
diameter (3.81 cm) of the optical cell reduced mixing and sensitivity,
both of which lead to poorer analysis. (4) The aeration flask specified
is fragile and would be very difficult to clean properly. It would be
a major problem in routine use. (5) Some commercially available
instruments use a recirculating, rather than a flow-through system.
Studies reported in the literature have shown recirculating systems
to be as valid as the once through system. Since the absorbance is read
when the Hg concentration reaches equlibrium, there is no need for a
recorder,.
(b) Alternative heating devices should be allowed because: (1) Other
devices achieve the same effect. For example, infrared lamps have
been used. The Agency 245.1 allows the use of a desiccant and a 60-
watt incandescent lamp to prevent condensation in the optical cell.
10
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(2) Moisture condensation is not normally a problem, and, therefore,
heating the optical cell is not necessary; this may be a particular
problem resulting from the proposed large diameter optical cell.
(c) The use of flexible Tygon tubing should be allowed as an
alternative to glass in the aeration cell-to-optical cell conncection
for the following reasons: (1) The EPA allows its use in Method 245.1
for Hg analysis of water and wastes. (2) Flexible tubing is necessary
for some of the comercially available systems. (3) The standard
practice of daily conditioning the system with 5 to 10 yg of Hg
eliminates any problems resulting from the choice of tubing.
(4) Use of flexible tubing allows for mixing by swirling the aeration
flask and eliminates the need for a magnetic stirrer. Silicone
tubing has been found to be completely satisfactory, too.
Response: The analytical equipment described in Methods 101,
101A, and 102 (aeration bottle, all glass tubing connection, single
pass system, optical cell heating) is significantly different from
that allowed in EPA 245.1. The equipment was designed to minimize
f
imprecision and inaccuracy in the analysis. Maximum accuracy and
precision is necessary because of sampling costs and the dilutions
required to bring the sample concentration into the range of the
flame AA. 'Method 101 is more accurate and precise than EPA 245.1
as can be seen by comparison of the precision and accuracy of both
methods.
n
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However, since the research' on Methods 101 and 102, commercially
available systems have been developed that are just as accurate and
precise. Therefore, substitution of these systems will be allowed
as long as they meet the guidelines stated in the response to
Comment 11.
Miscellaneous
14. D-2
Comment: The proposed changes will improve the accuracy and
precision of the sampling and analysis methods.
Response: No response needed.
15. D-4, D-5
Comment: The use of nitrogen is not essential. Dried, filtered,
Hg-free air is adequate.
Response: We agree. Section 5.3.9 has been revised to read,
"Aeration Gas Cylinder. Nitrogen or dry, Hg-free air, equipped with
a single stage regulator."
16. D-4, D-5
*
Comment: The use of an asbestos gasket with the probe nozzle
and asbestos insulation tape is inconsistent with the Agency's position
relative to the use of asbestos substitute materials. Many
laboratories have abandoned use of these products.
Response: Fiberglass tape may be substituted. Sections 5.3.2 and
7.1.3 have been revised to read "fiberglass tape" and "fiberglass
gasket," respectively.
12
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17. D-4, D-5
*.
Comment: For the flow-through system, measurement of the peak
area is far more precise and sensitive than the peak height. This
also eliminates the need for precise control of temperature and
volume.
Response: Our data showed that either peak height or area was
acceptable. Either may be used. The following sentence will be
added to the beginning of Section 8.3: "The mercury response may
be measured by either peak height or peak area."
18. D-4
Comment: The Method of Standard Additions should be detailed in
some way, perhaps as an appendix.
Response: The method is described in Citation 19 of Method 101.
19. D-3
Comment: Why is the source sample initially diluted with
deionized distilled water? This only serves to decrease the sensitivity
of the test. If all rinses were done with 0.1 M Id and the total
volume was then measured, a 2-ml aliquot of sample diluted to 250 ml
as described in the second dilution step would yield a 0.0008 M IC1
solution. If a 5-ml aliquot of this solution was pipetted into the
aeration flask (containing 50 ml of deionized water), the final
solution would be 0.00008 M IC1, which would not inhibit the reduction
of Hg.
13
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Response: These dilutions are needed to bring the sample
s
concentration into the range of the spectrophotometer. In doing
so, an accurate initial volume is needed. The source sample volume
after recovery is approximately 550 to 600 ml. Because the density
of this solution is uncertain after collection, weighing is not a
suitable method of determining volume. Similarly, the graduations on
a 0 to 1000 ml graduated cylinder that would be needed (if dilution
in a volumetric flask is not done) would be too large for accurate
measurement.
20. D-3
Comment: It would be helpful to state the minimum total ng
detectable in the aeration cell. This works out to about 20 ng.
Response: This depends upon the sensitivity of the system.
21. D-4
Comment: We recommend that the mercury stock solution be stored
in and pipetted into borosilicate glass bottles, and not plastic
bottles.
Response: This has been incorporated into the method.
22. D-3
«
Comment: In cleaning glassware, the Preparation of Sampling
Train Section and the Calibration and Standards Section do not agree.
The procedure in the latter section of prolonged soaking with
50 percent nitric acid should be the first step in cleaning glassware.
14
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Response: Equipment in the Preparation of Sampling Train
Section is not soaked because this would be difficult for probes.
Recovery studies have shown that the specified rinsing is an
acceptable method for avoiding contamination. Also, the washing
procedure is done after each sample while the sample recovery for
the previous run is being performed.
15
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TABLE 1. LIST OF COMMENTERS
Docket No. A-79-45
Document Number
IV-D-1
IV-D-2
IV-D-3
IV-D-4
IV-D-5
Commenter/Aff111ation
Donald L. Dustin, Jr., Manager, Stack Testing
Ecology and Environment, Inc.
195 Sugg Road
Post Office Box D
Buffalo, New York 14225
J.C, Brown, Manager, Environmental Technology
01 in Chemicals Group
Post Office Box 243
Charleston, Tennessee 37310
Barbara Dell/Acqua, Associate Chemist
New York State Department of Environmental
Conservation
50 Wolf Road
Albany, New York 12233
Edmund J. Laubusch, Technical Manager
The Chlorine Institute, Inc.
342 Madison Avenue
New York, New York 10173
Richard J. Samel son, Manager, Environmental
Programs
PPG Industries, Inc.
One Gateway Center
Pittsburg, Pennsylvania 15222
16-
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TECHNICAL REPORT DATA
(Please read Instructions on the reverse before completing;
1. REPORT NO. 2
EPA-450/3-82-008
4. TITLE AND SUBTITLE
Revisions to Methods 101, 101A, and 102 for
Determination of Mercury Emissions
Summary of Comments and Responses
7 AUTHORfS)
Emission Standards and Engineering Division
9. PERFORMING ORGANIZATION NAME AND ADDRESS
Emission Measurement Branch (MD-19)
Emission Standards and Engineering Division
U. S. Environmental Protection Agency
Research Triangle Park, N. C. 27711
12. SPONSORING AGENCY NAME AND ADDRESS
DAA for Air Quality Planning and Standards (MD-10
Office of Air, Noise, and Radiation
U. S. Environmental Protection Agency
Research Triangle Park, N. C. 27711
3. RECIPIENT'S ACCESSION NO.
5. REPORT DATE
February 1982
6. PERFORMING ORGANIZATION CODE
8. PERFORMING ORGANIZATION REPORT NO.
10. PROGRAM ELEMENT NO.
11. CONTRACT/GRANT NO. ;
f
13. TYPE OF REPORT AND PERIOD COVEREr ,'
}
14. SPONSORING AGENCY CODE
EPA/200/04
15 SUPPLEMENTARY NOTES
16. ABSTRACT
This document addresses the public comments s
of the mercury methods in the Federal Register. Ch
as a result of these comments are included. This <
basis for the revisions which have been made to th<
proposal and promulgation.
jbmitted after proposal
anges made to the methods
document serves as the
3 test methods between
17. KEY WORDS AND DOCUMENT ANALYSIS
a. DESCRIPTORS b.lDENTIFI
18 DISTRIBUTION STATEMENT 19. SECURT
Release Unlimited Uncla
20. SECURI-
Uncla
EPA Form 2220-1 (Rev. 4-77) PREVIOUS EDITION is OBSOLETE
ERS/OPEN ENDED TERMS C. COSATI Field/Group
13B
FY CLASS (This Report) 21. NO. OF PAGES
ssified 20
PY CLASS (This page) 22. PRICE
ssified
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