United States
Environmental Protection
Agency
Environmental Monitoring Systems
Laboratory
Research Triangle Park NC 27711
Research and Development
EPA-600/S4-84-080 Nov. 1984
Project Summary
Validation of an Emission
Measurement Method for
Inorganic Arsenic from
Stationary Sources: Proposed
Method 108—Laboratory and
Field Test Evaluations
T. E. Ward, R. K. M. Jayanty, P. M. Grohse, W. F. Gutknecht, C. L Bruffey,
T. J. Wagner, and J. W. Prohaska
The U.S. Environmental Protection
Agency's Proposed Method 108 for
measurement of inorganic arsenic emis-
sions from stationary sources has been
evaluated both in the laboratory and
field. Details of the evaluations are given
through analysis of laboratory samples,
preparation of filter and impinger audit
samples for field use and stability
studies, and two field tests of the
method using dual and quad sampling
trains at a copper smelter plant and a
glass manufacturing plant. Several con-
clusions and recommendations have
been made regarding the method.
This Project Summary was developed
by EPA's Environmental Monitoring
Systems Laboratory, Research Triangle
Park, NC, to announce key findings of
the research project that is fully docu-
mented in a separate report of the same
title (see Project Report ordering in-
formation at back).
Introduction
The Environmental Monitoring Systems
Laboratory (EMSL) of the U.S. Environ-
mental Protection Agency has determined
the industries and processes of stationary
sources which emit significant inorganic
arsenic emissions. Included among these
are the five most significant sources
chosen by EPA's Office of Air Quality
Planning and Standards (OAQPS) for
original consideration for regulation of
inorganic arsenic emissions: glass plants,
secondary load smelters; primary copper
smelters; cotton ginning activities; and
zinc oxide manufacturing. Presently
OAQPS is recommending only primary
copper smelters and glass plants for these
regulations.
A primary concern of EMSL has been
validation of the procedure used for sam-
pling and analysis of the arsenic-contain-
ing emissions. EMSLdeterminedthatthe
proposed EPA Method 108, which in-
volves collection in impinger solutions
and on filters and measurement using
atomic absorption spectrophotometry,
was the best available method for measur-
ing these arsenic emissions. Therefore a
program to validate this method was
designed by EMSL. The validation ap-
proach included a multicomponent project
which involved both laboratory and field
studies. Research Triangle Institute re-
viewed reports describing sampling and
analysis of arsenic, evaluated EPA
Method 108 through analysis of labora-
tory samples, prepared audit samples for
field use and studied the stability of audit
samples. PEDCo Environmentalists, Inc.,
collected samples at a copper smelter and
a glass manufacturing plant and analyzed
the collected samples.
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Results and Discussion
Laboratory studies conducted to evalu-
ate the performance of EPA Method 108
included: recovery and measurement of
audit materials; stability of audit mate-
rials, precision of the method from sample
preparation to measurement, and recom-
mendations regarding analytical aspects
of the method. Standard samples contain-
ing arsenic with loadings approximating
emissions expected at field test sites
were prepared in the laboratory. A total of
36 impinger samples and 36 filter sam-
ples at six different concentrations were
prepared. Concentrations ranged from
0.013 mg to 5.0 mg arsenic for the
impinger samples and from 1.4 mg to 52
mg arsenic for the filter samples. Am-
pules were used to contain the impinger
samples. Selected filter and impinger
samples from each concentration set
were analyzed by atomic absorption
spectrophotometry. The precision of the
measurement phase of Method 108 was
determined from triplicate analyses of
standards. The relative standard deviation
(RSD) of the analytical method was
approximately 1.0 percent in the 40- to
100-micrograms arsenic per milliliter
range. The stability of both simulated
sample types (impinger and filter) for
potential use as audit materials for EPA
Proposed Method 108 was also evaluated
over a six-month period. Stability as a
function of sample type, concentration
level and time was evaluated. Changes in
concentration level and time was evalu-
ated. Changes in concentration were not
found to be statistically significant over a
six-month period forlilter type materials
except at the highest loading (25 mg). For
impinger materials there were no signifi-
cant losses over the same time period.
Two field tests to validate proposed
Method 108 at different sites were con-
ducted. The first field test was conducted
at a primary copper smelter (Plant No. 1)
and the second test was conducted at a
glass manufacturing facility (Plant No. 2).
During the field test series, PEDCo con-
ducted a total of 14 tests of proposed
Method 108 (seven paired runs) at Plant
No. 1 and a total of 36 tests of proposed
Method 108 (nine quad-train runs) at
Plant No. 2 to determine the precision of
the methodology for measuring arsenic
concentrations. A comparison of the
statistical results for total arsenic from
Plant No. 1 indicates that the within-run
RSD for the seven sample runs ranged
between 3.9 and 22.8 percent with the
value for precision of the Method at 15.7
percent. Standard deviations of paired
runs had a low value of 0.36 mg/dNm3, a
high of 4.06 mg/dNm3, and a pooled
mean of 1.90 mg/dNm3. The mean
arsenic concentration of paired runs
ranged from 3.08 to 18.3 mg/dNm3 based
on total arsenic, and the overall mean
value was 10.5 mg/dNm3. Considering
the sampling site constraints and variable
process operation, the results indicate
that an acceptable degree of precision
was achieved at this source.
The standard deviations of the quad run
(Plant No. 2) had a low value of 0.10
mg/dNm3, a high value of 0.51 mg/dNm3,
and a pooled mean value of 0.37
mg/dNm3. The RSD values ranged from
0.95 to 5.5 percent with the value for the
precision of the Method at RSD value of
3.85 percent. The mean arsenic concen-
tration of the individual quad runs ranged
from 9.18 to 10.55 mg/dNm3 with an
overall mean of 9.67 mg/dNm3, which
indicated a generally consistent process
operation throughout the test period.
Once again, the results indicated that an
acceptable degree of precision was
achieved. The detailed results of all tests
are presented in the project report.
Conclusions and
Recommendations
Several conclusions and recommenda-
tions have been made regarding the
proposed EPA Method 108 for the deter-
mination of arsenic emissions from
stationary sources. These include: (1) the
method is relatively straight-forward and
is reasonable with respect to time and
cost; (2) greater care of the sample during
preparation than the proposed method
requires, should be exercised, including
avoidance of bumping and spattering
during the evaporation process; (3) filter
and impinger audit samples were found
to be stable over a six-month period; and
(4) an acceptable degree of precision of
Method 108 is achieved from the field
tests. Graphite furnace atomic absorption
techniques have an improved analytical
range over hydride techniques, are more
rapid and therefore are recommended to
be an adequate measurement substitute.
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The EPA author T. E. Ward (also the EPA Project Officer, see below) is with the
Environmental Monitoring Systems Laboratory, Research Triangle Park, NC
27711;R. K. M. Jayanty. P. M. Grohse, and W. F. Gutknecht, are with Research
Triangle Institute. Research Triangle Park, NC 27709; C. L Bruffey, T. J.
Wagner, andJ. W. Prohaska are withPEDCoEnvironmentalists, Inc., Cincinnati,
OH 45246.
The complete report, entitled "Validation of an Emission Measurement Method
for Inorganic Arsenic from Stationary Sources: Proposed Method 108—
Laboratory and Field Test Evaluations." (Order No. PB 85-115 160; Cost:
$ 11.50, subject to change) will be available only from:
National Technical Information Service
5285 Port Royal Road
Springfield, VA 22161
Telephone: 703-487-4650
The EPA Project Officer can be contacted at:
Environmental Monitoring Systems Laboratory
U.S. Environmental Protection Agency
Research Triangle Park, NC 27711
U.S. GOVERNMENT PRINTING OFFICE; 1984 — 559-016/7845
United States Center for Environmental Research
Environmental Protection Information
Agency Cincinnati OH 45268
Official Business
Penalty for Private Use $300
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