6ERA
United States
Environmental Protection
Agency
Environmental Sciences Research
Laboratory
Research Triangle Park NC 27711
EPA-600/3-80-023
January 1980
and Development
Biogenic Hydrocarbon
Contribution to the
Ambient Air of
Selected Areas
Tulsa; Great Smoky
Mountains; Rio Blanco
County, Colorado
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RESEARCH REPORTING SERIES
Research reports of the Office of Research and Development, U.S. Environmental
Protection Agency, have been grouped into nine series. These nine broad cate-
gories were established to facilitate further development and application of en-
vironmental technology. Elimination of traditional grouping was consciously
planned to foster technology transfer and a maximum interface in related fields.
The nine series are:
1. Environmental Health Effects Research
2. Environmental Protection Technology
3. Ecological Research
4. Environmental Monitoring
5. Socioeconomic Environmental Studies
6. Scientific and Technical Assessment Reports (STAR)
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This report has been assigned to the ECOLOGICAL RESEARCH series. This series
describes research on the effects of pollution on humans, plant and animal spe-
cies, and materials. Problems are assessed for their long- and short-term influ-
ences. Investigations include formation, transport, and pathway studies to deter-
mine the fate of pollutants and their effects. This work provides the technical basis
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This document is available to the public through the National Technical Informa-
tion Service, Springfield, Virginia 22161.
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EPA-600/3-80-023
January 1980
BIOGENIC HYDROCARBON CONTRIBUTION TO THE AMBIENT AIR OF SELECTED AREAS
Tulsa
Great Smoky Mountains
Rio Blanco County, Colorado
by
Robert R. Arnts
Sarah A. Meeks
Atmospheric Chemistry and Physics Division
Environmental Sciences Research Laboratory
Research Triangle Park, North Carolina 27711
ENVIRONMENTAL SCIENCES RESEARCH LABORATORY
OFFICE OF RESEARCH AND DEVELOPMENT
U.S. ENVIRONMENTAL PROTECTION AGENCY
RESEARCH TRIANGLE PARK, NORTH CAROLINA 27711
-------
DISCLAIMER
This report has been reviewed by the Environmental Sciences Research
Laboratory, U.S. Environmental Protection Agency, and approved for publica-
tion. Mention of trade names or commercial products does not constitute
endorsement or recommendation for use.
11
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PREFACE
Scientists have hypothesized for a number of years that the atmospheric
loading of nonmethane hydrocarbons from biogenic sources is as large or
even larger than emissions from anthropogenic sources. Evidence cited
to support this hypothesis includes the phenomenon of blue haze observed
in the Smoky Mountains, high total nonmethane hydrocarbon concentrations
measured in rural areas, and even detailed chromatographic analyses of air
in rural areas that supposedly identify specific biogenic hydrocarbons.
The sampling efforts described herein were undertaken to determine the
credibility of these speculations. In particular these studies addressed
the questions: Do biogenic hydrocarbons constitute a large portion of
the total nonmethane hydrocarbon concentration in these areas? What portion
of the total nonmethane hydrocarbons can be attributed to auto exhaust?
iii
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ABSTRACT
Estimates of volatile hydrocarbon emissions to the atmosphere indicate
that biogenic sources are much greater on a global basis than anthropogenic
sources. Many assumptions inherent in these estimates, however, introduce
a large degree of uncertainty about both inventories.
A critical review of the literature reveals nonmethane hydrocarbons in
rural and remote areas consist mainly of anthropogenic species, and are
composed of less than 10% biogenically-related compounds (i.e., monoterpenes
and isoprene). Despite these results, some investigators continue to invoke
"natural hydrocarbon emissions" to explain naturally occurring haze,
incorrectly identified gas chromatographic peaks, and high concentrations
of total nonmethane hydrocarbons that are measured by indiscriminate (total
hydrocarbon-methane) analyzers.
In response to the suggestion that biogenic emissions are responsible
for the high hydrocarbon concentrations described in several reports, the
Environmental Sciences Research Laboratory of the U.S. Environmental Pro-
tection Agency initiated short-term sampling as a means of validation. A
limited number of whole-air samples were collected in Tedlar bags and analyzed
by gas chromatography with flame ionization detection.
The areas of study included: Tulsa, Oklahoma; Rio Blanco County,
Colorado; and the Great Smoky Mountains in Tennessee. Tulsa air was found
to contain an average of 0.2% isoprene of the total nonmethane hydrocarbon
load. Rio Blanco County and the Smoky Mountain air, respectively, averaged
about 2% and 4% biogenic hydrocarbon of the total nonmethane hydrocarbon
loads. Isoprene appears to be a dominant olefin in rural and remote areas.
Although the tests were of short duration, the results suggest mono-
terpenes and isoprene constitute minor components of rural air relative to
anthropogenic hydrocarbons.
iv
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CONTENTS
Preface iii
Abstract iv
Figures vi
Tables vii
Acknowledgment viii
1. Introduction 1
2. Conclusions 5
3. Recommendations 7
4. Experimental 8
Materials 8
Procedures 8
5. Sampling Locations 10
Tulsa, Oklahoma 10
Rio Blanco County, Colorado 10
Great Smoky Mountains National Park, Tennessee 14
6. Results and Discussion 17
Tulsa, Oklahoma 17
Rio Blanco County, Colorado 20
Great Smoky Mountains National Park, Tennessee 26
References 30
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FIGURES
Number Page
1 Tulsa, Oklahoma sampling locations 11
2 Rio Blanco County, Colorado 12
3 Oil Shale mineral right ownership 13
4 Tract Cb sampling locations 15
5 Great Smoky Mountain National Park: Elkmont sampling site 16
vi
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TABLES
Number Page
1 Summary of Biogenic Hydrocarbon Concentrations in Ambient Air.... 3
2 Hydrocarbon Composition of Tulsa Area Air ........................ ^°
3 Summary and Analysis of Tulsa Hydrocarbon Data ................... -*•"
4 Hydrocarbon Composition of Rio Blanco County, Colorado Air ....... 22
5 Summary and Analysis of Rio Blanco County, Colorado
Hydrocarbon Data ............................................... 23
6 Hydrocarbon Composition of Smoky Mountain Air
7 Summary and Analysis of Smoky Mountain Hydrocarbon Data
vii
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ACKNOWLEDGEMENT
We wish to thank Mr. Ray Bishop of the Tulsa City-County Health
Department, and Mr. Miles D. LaHue of U.S. Geological Survey, Grand Junction,
Colorado, for their assistance in these sampling efforts. We also wish to
thank Mrs. Anita McElroy for typing this document.
viii
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SECTION 1
INTRODUCTION
In 1960 Went proposed that vegetation releases 165 x 10 ton/yr of
volatile organic matter globally, in the form of terpenes (1). He speculated
the hydrocarbons thus liberated could be responsible for the formation of
atmospheric blue haze created as a result of terpene-ozone oxidation products
(2)- Hazes of this type are especially prevalent over areas such as the
Smoky Mountains of Tennessee and the eucalypt forests of Australia.
Through the I960's>Went's original estimates were revised upward by
Rasmussen and Went (3) and by Ripperton et al. (4). All of the estimates
were crude, as the authors pointed out, being based upon a number of
tenuous assumptions. Nevertheless, in 1968 at the Stanford Research In-
stitute, (5) in a literature review conducted for the American Petroleum
Institute annual biogenic emissions were determined as exceeding anthro-
pogenic emissions on a worldwide basis (120 x 10 tons vs 27 x 10 tons).
Since the above report, further studies have attempted to refine these
estimates and reduce some of the uncertainties inherent in them. The
result has been to revise the biogenic estimates upward further, while
only marginally improving the uncertainties.
Chief among the uncertainties is the generation of scaling factors
used to extrapolate the emission of a branch or small forest plot to a large
area of diverse and discontinuous vegetation. The short-comings in the
accuracy of the emission inventories (biogenic and anthropogenic) are
supported by actual measurements of ambient hydrocarbons in rural and
remote areas. Although the data base is not large, published measurements
of total nonmethane hydrocarbons (TNMHC) within forested areas have never
shown more than a 40 to 50% contribution of biogenic hydrocarbons. Typically
the contribution is less than 10%, even in densely forested areas. Measure-
ments of detailed hydrocarbon concentrations where isoprene and monoterpenes
-------
were specifically sought out are summarized in Table 1. Studies where
only TNMHC was measured are excluded because (1) high TNMHC in rural or
remote areas may be the result of urban influences and (2) the accuracy
of the TNMHC method has been seriously questioned (6,7).
In examining the compounds and concentrations reported, consideration
must be given to the type of vegetation in the sampling area and its
density upwind of the sampling location; furthermore, concentrations are
strongly influenced by the degree of atmospheric mixing, the season and
temperature. Lastly, the techniques used in making the hydrocarbon measure-
ments should be examined along with the experience of the investigators
employing those techniques. Most groups have used gas chromatographic (GC)
separation with flame ionization detection (FID); however, the column types
employed have a wide range of resolution. The lowest resolution is gen-
erally obtained with the short (2-6 m) packed columns. High resolution is
obtained with the support-coated open tubular (SCOT) or wall-coated open
tubular (WCOT) columns. Thus the probability of interferences occuring
with a packed column are much higher than with a SCOT or WCOT column.
Interestingly, when average concentrations of biogenic hydrocarbons
are examined in Table 1, the highest are reported by those studies where
packed columns were employed (Rasmussen and Went (3), Whitby and Coffey(lO)),
Indeed average concentrations from such studies are ten to one hundred
times higher than groups using high resolution columns. Furthermore,
Rasmussen's later studies and those of his coworkers at Washington State
University employing high resolution GC never reported concentrations of
those magnitudes, i.e. Rasmussen et al. (9) and Holdren et al. (15). The
work of Whitby and Coffey (10) should be viewed with some caution since
these experimenters did not match retention times on their packed column,
but chose to group compounds as 'terpene species' when eluting after a
particular time, or as 'lighter species' when eluting before this time.
Because of the rural nature of the site, they discounted urban influences
and believed their data reflected only natural sources.
If the work of Rasmussen and Went (3) and Whitby and Coffey (10) is
discounted, the data reported in Table 1 agree reasonably well. Isoprene
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Table 1. SUMMARY OF BIOGENIC HYDROCARBON CONCENTRATIONS IN AMBIENT AIR
Authors/Sampling location(s)
Rasmussen & Went
Ozark Plateau, Missouri
'
Gray Summit, Missouri
Highland Biological St., NC
Gray Summit, Missouri
Rasmussen, Chatfield et. al.
Elkton, Missouri
Lonneman et. al.
Chickatawbut Hill, Mass.
Whitby & Coffey
Adirondack Mountains, NY
Lonneman, Seila, Bufalini
St. Petersburg/Tampa, Miami
and the Everglades, Florida
Schjoldager & Wathue
Gjerdrum, Norway
Seila
Jones State Forest,
(38 mi North of Houston, TX)
Holdren, Westberg & Zimmerman
Moscow Mountain, North-Central
Idaho
Reference
number
( 3)
( 8)
( 9)
(10)
(11)
(12)
(14)
(15)
Surrounding vegetation
Hardwood forest &
prairie
Junipers & meadow
Hardwood forest
Hardwood forest &
meadow
Hardwoods & farmland
Oak & other hardwoods
Coniferous forest
Deciduous/coniferous
forest
Orange groves, gum,
Cyprus, oak, wax
myrtle, black willow.
persimmon
Coniferous forest
(spruce & farmland)
Loblolly pine
Coniferous forest
(pine and fir)
Biogenic
hydrocarbon
isoprene )
a-pinene /
p-pinene >
limonene \
myrcene J
totaled
totaled
totaled
isoprene
isoprene
'terpene
species'
'lighter
species'
'terpene
species'
'lighter
species'
isoprene
d-limonene
a-pinene
0-pinene
a-pinene
(3-pinene
limonene
isoprene
a-pinene
isoprene
a-pinene
(5-pinene
3-carene
limonene
a-pinene
(3-pinene
3-carene
limonene
Avg. cone..
ppbC
totaled
106
41
50
109
6
10
33
63
12
18
1.6
0
0
0
14.0
9.5
3.6
0.1
1.13
0.86
0.64
0.10
1.23
1.73
1.08
0.10
Max
ppbC
150
60
120
340
28
34
(1
day)
72
123
17
21
4.5
16.5
19.5
trace
7.7
1.2
7.3
4.6
5.4
0.5
2.7
5.7
3.7
0.2
Min
ppbC
70
30
10
10
0
< 1
5.3
29.3
6.5
14
< 0.1
•-
10.5
3.0
< 0.5
< 0.1
< 0.1
TNMHC
ppbC
--
--
-
98
-
106
••
-
-
--
357
%
biogenic
--
-
6
4
(max)
-•
2
%
automotive
-
12
-
61
35
O.ll samples collected within the forest
< O.H 3ft above the ground.
< O.l(
< 0.1J
0.3]
< O.ll samples collected within 1 inch of
< 0. 1 ( the forest floor leaf litter
< 0.1J
Comments
Lowest levels observed just before sunrise;
high levels observed when deciduous
foliage changes color in the autumn; high
level of volatiles observed after grass was
mowed; packed column gc-fid.
79 measurements; most intensive study
yet performed; gc-fid high resolution
SCOT column.
WCOT column; highest levels observed
during daylight hours.
Chromatographic peaks not identified;
authors assumed biogenic origin due
mainly to rural location; packed column
gc-fid.
gc-fid; WCOT column-,.
High resolution glass capillary column
used; 3 data points.
qc-fid; WCOT columns.
Samples collected outsuli; the fnn;si
contamucl no nu'asmahli1 tiMpi.-m.-s
(less than 0.1 pphCI. (|c m1. with smi|li'
ion pr.'ak momtui inq
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averages fall between 0.1 and 10 ppbC, except for extremes as high as 34
ppbC and less than 0.1 ppbC in areas where isoprene-emitting vegetation was
present. Alpha-pinene, being the predominate monoterpene, averages between
less than 0.1 ppbC to 14 ppbC, with maximums as high as 16.5 ppbC (reported
in Norway).
The above summarized concentrations with the exceptions noted represent
biogenic contributions to the TNMHC burden of less than 10X in their
respective areas. Recently, however, the Environmental Sciences Research
Laboratory has been requested to perform detailed hydrocarbon analyses
of ambient air from several areas of the United States suspected of
carrying a large fraction of biogenic hydrocarbons. This report details
the results of those analyses. The samples were collected during July
1978 in Tulsa, Oklahoma, and around the Piceance Creek area of Rio Blanco,
Colorado; samples were also collected and analyzed from the Great Smoky
Mountains in Tennessee during the last week of September 19th.
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SECTION 2
CONCLUSIONS
Three areas of the United States were studied to determine if the am-
bient air contained significant concentrations of hydrocarbons of a bio-
genie nature. None of these areas was found to contain a large fraction of
biogenic nonmethane hydrocarbon. The Tulsa, Oklahoma air samples consisted
of 30 to 55% auto exhaust in the city and 8 to 24% auto exhaust at a downwind
rural location. Most of the balance of the TNMHC appears to be composed of
paraffins, similar to the refinery/tank farm emissions. Biogenic hydrocarbons
(isoprene) contributed an average of only 0.2% to the TNMHC (ranging from
0 to 0.5%). Of the eight samples collected in Tulsa, isoprene was detected
in only four samples; the highest concentration observed was 1.2 ppbC.
The samples collected in Rio Blanco County, Colorado, and the Smoky
Mountains, Tennessee, contained low Tis'MHC concentrations. Rio Blanco County
samples ranged from 117 to 138 ppbC. Twenty to thirty percent could be
attributed to auto exhaust; most of the balance of the TNMHC was within the
paraffin range, suggesting distant urban sources or local natural gas
activities. Isoprene, present in most samples in amounts ranging from 0.1
to 5.6 ppbC, contributed approximately 2% to the already low ambient TNMHC
concentration.
The Smoky Mountain samples similarly contained low TNMHC concentrations,
ranging from 87 to 171 ppbC. Although a large fraction of this total
apparently can be attributed to auto exhaust, the acetylene tracer technique
used to verify the origins of this chemical could not be employed accurately,
since local wood-burning campfires were also likely to be significant sources
of acetylene. Biogenic emissions nevertheless contributed an average of 4% to
the TNMHC, and a maximum of 6% in the form of isoprene and alpha-pinene.
Note: p-xylene and alpha-pinene have the same GC retention time, which
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could create too high a biogenic estimate for this series of analyses.
Isoprene was the predominant olefin species in 50% of the Colorado
samples and 33% of the Smoky Mountain samples. However, in both cases the
concentration never exceeded 7 ppbC.
Although this study represents a relatively short-term effort, the
results suggest that biogenic hydrocarbons (isoprene and the monoterpenes)
constitute less than 10% of the TNMHC burden of rural air. These results
are consistent with most previously-reported concentrations in forested
rural areas.
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SECTION 3
RECOMMENDATIONS
This study again serves to point out that urban centers influence
ambient pollution levels in distant rural or remote areas. Investigators
have often erroneously attributed high hydrocarbon levels in these areas
to natural sources, simply because of the remote geography. However, in
the case of the high TNMHC levels reported in Rio Blanco County, Colorado,
transport from urban centers does not explain levels on the order of 8
ppmC, nor, as suggested by this study, do biogenic sources. Rather, the
monitoring station reporting these high TNMHC levels was apparently sampling
its own etylene effluent from the ozone monitor. It therefore cannot be
overemphasized that such monitoring stations should take extreme care in
C'hecking plumbing for leaks and in installing properly functioning ethylene
combustors on monitor exhaust. Alternatively, a monitor that does not use
ethylene could be used for sampling, such as UV absorption instrumentation.
In future investigations, it is also recommended that analyses for
ambient hydrocarbons larger than C_ take advantage of the high resolution
capabilities of capillary column GC. Application of this technology, by
significantly reducing interferences, can improve confidence in identifying
compounds by retention time. However, as pointed out by the initial
Research Triangle Institute (RTI) misidentification of isoprene, measure-
ments by retention time, even with a high resolution column, can still
lead to incorrect identification. Additional confirmational techniques
must be used where possible to provide supporting information, e.g., gas
chromatography-mass spectrometry (GC-MS).
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SECTION 4
EXPERIMENTAL
MATERIALS
Air samples were collected in 20-L Tedlar bags (Dupont 2 mil poly-
vinyl fluoride film). These were constructed by heat sealing a 1 m x 0.5 m
sheet to form a 0.5 m square bag. Sample access was by way of a nut-secured
0-seal straight thread adapter connected to a Swagelok quick connect. The
bag was covered with 5 mil black polyethylene to protect the sample from
sunlight. As Seila (13) has observed, Tedlar tends to contaminate air
samples with acetone and acetaldehyde; the data reported for these compounds
should be taken as upper limits.
The bags were evacuated and filled using a Teflon-lined Thomas dia-
phragm pump (Model 107CDC18TFE). The speed of the 12 V DC pumping motor
was controlled by a variable rheostat (Ohmite, 100 W Model K, 10 Ohm). For
the Smoky Mountain samples, a Metal Bellows pump (MB-41) was used for filling
and evacuating the bags. Power for the Thomas pump was supplied by a 12 V
auto battery; the metal bellows pump operated on 120 V AC.
Detailed hydrocarbon analyses were performed using the GC procedures
described previously (14)- Briefly, 3 column analysis of a cryogenically-
concentrated air sample was performed to separate the C2-C... paraffins,
olefins, and aromatics.
PROCEDURES
Before sampling, the bag was examined for leaks by checking for air
pockets in the evacuated bags. The pump was started and the flow rate
checked and adjusted as required. The 3 m, 0.64cm o.d. FEP tubing sampling
inlet was placed upwind of the pumping system, then allowed to purge for a
few minutes. Afterwards, the bag was connected and allowed to fill to
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about 1/2 volume (10 L). The bag was filled to only 1/2 volume to allow
for expansion when the bag was shipped by air freight for analysis.
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SECTION 5
SAMPLING LOCATIONS
TULSA, OKLAHOMA
Of the four sampling sites chosen in the Tulsa area, three had been
used earlier by RTI in a 1977 study (16). These were: the City-County
Health Department, the Post Office, and Liberty Mounds (See Figure 1).
These sites were chosen since RTI reported measuring very high concentrations
of isoprene and ethylene during their earlier field study. The Post
Office is located in the downtown section of Tulsa, while the City-
County Health Department is within the city limits, but near the suburbs.
The Liberty Mounds location is a rural area that is usually upwind of
Tulsa, but was downwind during this study. The sampling site is about 37 km
south of Tulsa. The fourth sampling location was a roadside approximately
0.8 mile downwind of the Texaco refinery complex in Tulsa; grab samples
were collected there to obtain a rough characterization of refinery
emissions.
RIO BLANCO COUNTY, COLORADO
The Piceance Creek basin of Rio Blanco County, Colorado, is located
approximately 80 km northeast of Grand Junction, Colorado, and 24 km north
of Rifle (see Figure 2). The terrain is rocky and arid, possessing only
sparse vegetation: sage brush, coarse grass, pinyon pine and some juniper.
Much of the land in this area is federally owned, of which a part is
leased to oil companies for possible shale oil development (see Figure 3).
One area for potential development is a tract referred to as Cb,
which is leased to Occidental Oil and Ashland Oil (0 & A). In order to
estimate the impact of oil shale development on air quality, 0 & A
established an air monitoring station at Cb in 1974 to gather baseline
data on the criteria pollutants. The station has since been recording
10
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SCALE
mi 0 5 10 20
: | 1 1 1
km 0 8 16 32
KANSAS
OKLAHOMA
BARTLESVILLE
PONCA CITY
TULSA
POST OFFICE* • HEALTH DEPARTMENT
MUSKOGEE
LIBERTY MOUNDS
Figure 1. Tulsa, OK sampling locations.
11
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DE BEQUE
•GRAND
JUNCTION
OIL SHALE
DEPOSITS
Figure 2. Rio Blanco county, Colorado.
12
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FEDERAL LANDS
(WHEN LOCATED WITHIN WITHDRAWAL
AREA)
MAXIMUM THICKNESS (IN FEET) OF CON-
TINUOUS OIL SHALE SECTION AVERAG-
ING AT LEAST 25 GALLON OF OIL PER
TON (FROM BUMINES R.I. 7357)
CURRENT BOUNDARIES OF THE FEDERAL
TJnifei OIL SHALE WITHDRAWAL—
^=*T-«::?:-frr^ •
TZfiflfM. •<&%!.'&&*',
Figure 3. Oil Shale mineral right ownership.
13
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periodic TNMHC excursions in concentrations as high as 4 to 7 ppmC,
while the other pollutant concentrations are very low. Additional
samples were collected upwind of the monitoring station approximately
4.5 km to the south, and at a site 4.3 km north in the valley (see
Figure 4). Also, one sample was taken downwind of the Mobil Oil natural
gas processing facility at Piceance Creek (about 9.6 km NNE of the
monitoring station).
GREAT SMOKY MOUNTAINS NATIONAL PARK
Samples were collected in Sevier County, Tennessee in the Great
Smoky Mountains National Park. The sampling site was at a National Park
Service building at Elkmont about 10 km southwest of Gatlinburg, Tennessee.
Elkmont Campground is nearby (see Figure 5). At an elevation of about
762 m, the surrounding 5 km is lushly forested with species that include:
Canada hemlock, eastern hemlock, pitch pine, white ash, yellow buckeye,
sugar maple, basswood, yellow birch, yellow-poplar, American beech,
mountain silverbell, black cherry, mountain laurel, northern red oak,
rhododendron, and cucumber tree.
14
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SCALE
mi 0
| p
km 0 1
GAS FIELD
t
NORTH
I.
TRAILER 020
SITE SG -18
Figure 4. Tract Cb sampling locations.
15
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Lockout Rock .;, . ."Hiking Club
- • Cabin
ELKMONT^fu^yG.
o.iS» Vl vi"
<.--'/ K IK -
J X. ' ColdSprin:
' • W I ^. ,' ^ l^Wnl
'S^C -^ -L*Z,<-#^/-
:AROLINA^—^^ VCL'IN
.AROLNAj^B, TO vV
:ky Tep
.
Tl
. - - , >» )l\l6RTiTcAROLiNA^i^"55\ ir- "•^•""
.^* ; / £ * • ' ' ...w.- \J^..w.
Figure 5. Great Smoky Mountain National Park: Elkmont sampling site.
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SECTION 6
RESULTS AND DISCUSSION ,
TULSA, OKLAHOMA
On July 27, 30-min integrated air samples were collected at three
sites in and around Tulsa, Oklahoma. Two consecutive samples were collected
at the City-County Health Department, two at the downtown Post Office and
two at the rural Liberty Mounds site approximately 37 km south of Tulsa.
The winds were out of the north, in contrast to more typical southerly
winds in the area. The Liberty Mounds site, used as an upwind station in
the RTI study, therefore represents the downwind plume of Tulsa in these
samples. In addition to the three sites, which had been used by RTI, two
grab samples were collected downwind of the Texaco Refinery in Tulsa to
obtain a hydrocarbon fingerprint of refinery emissions.
Table 2 presents detailed hydrocarbon profiles of the samples collected.
Of particular interest are the low values of isoprene observed; in contrast
to preliminary average values of 74 to 118 ppbC observed by RTI, the highest
concentration observed in this study was only 1.2 ppbC. Also, only 1 ppbC
of ethylene was observed at the rural Liberty Mounds site, whereas RTI
reported a preliminary average of 2028 ppbC.
Table 3 presents summations of the paraffins, olefins, and aromatics,
and their ratios to acetylene. By normalizing to acetylene, as described
by Lonneman (18), the contribution of tailpipe emissions to the TNMHC can be
estimated. As is apparent most of the aromatics and olefins can be attributed
to tailpipe emissions in the Health Department and Post Office samples.
However, the paraffins appear to have other sources, such as natural gas
emissions, gasoline evaporative emissions, or possibly the refinery operations
(as indicated by their heavy emissions in the paraffinic range). The
consecutive samples collected at Liberty Mounds seem to indicate transport
17
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Table 2. HYDROCARBON COMPOSITION OF TULSA AREA AIR
Location:
Date:
Wind:
Compound
Paraffins
ethane
propane
isobutane
n-butane
isopentane
n-pentane
cyclopentane
2-methylpentane
3-methytpentane
n-hexane
2,4-dimethylpentane
methylcyclopentane
cyclohexane
2-methylhexane
2,3-dimethylpentane
3-methylhexane
cis-1.3-dimethl-
cyclopentane
2.2,4-trimethyl-
pentane
trans- 1 ,3-dimethyl-
cyclopentane
n-heptane
methylcyclohexane
nonane
decane
undecane
1 paraffins
Olefins
ethylene
propylene
isobutylene
trans-2-butene
cis-2-butene/butadiene
1-pentene
2-methyl-1-butene
trans-2-pentene
cis-2-pentene
2-methyl-2-butene
isoprene
4-methyl-2-pemene
1 -hexene
trans-2-hexene
cis-2-hexene
1 Olefins
Aromatics
toluene
ethylbenzene
p-xylene
m-xylene
o-xylene
isopropy (benzene
n-propylbenzene
m+p-ethyltoluene
1 ,3,5-trimetnylbenzene
o-ethyltoluene
1 ,2,4-trimethylbenzene
m-ethyltoluene
1 aromatics
Oxygenates
acetaldehyde
1 oxygenates
1' Unknown-gc peaks (N)
acetylene
Total NMHC
City-County
Health Department
7-27-78
From N to NNE. lights
Post Office
7 71 7Q
/-Z/-/U
Liberty Mounds
7-27-78
From N to NE. light
Time
8:25-8:55 AM
11.7
15.5
8.1
16.5
17.3
12.2
2.5
6.4
4.6
8:55-9:25 AM
10.2
14.2
8.3
19.1
20.1
18.4
3.2
8.0
5.6
6.1 ! 6.2
5.2 | 5.5
0 0
1.8 ! 3.3
5.0
3.3
5.7
1.0
4.6
2.0
6.1
8.7
1.9
2.3
Z2
150.6
11.5
4.2
1.2
1.6
0
0.8
0.6
0
0
0
1.2
0
0
0.4
0
21.6
13.8
2.6
1.6
5.3
3.3
0
0
0
1.9
0
7.1
3.3
39.0
7.0
iai
25.1
42.3116)
8.4
287.0
4.9
3.3
5.4
0.7
4.1
1.2
4.9
4.5
1.4
2.0
0.8
155.2
8.6
5.6
1.5
1.6
0
0.8
1.1
0
0
0
1.0
0
0.5
0.3
0
21.0
13.0
2.6
2.4
5.2
3.2
0
0.9
0
1.4
0
3.7
0.5
32.8
8.3
14.6
22.9
13.0(5)
8.4
253.4
9:53-10:23 AM
10.7
9.6
14.1
51.7
65.8
40.8
5.8
23.9
13.8
14.8
17.8
0
0
17.1
7.4
15.0
4.3
as
3.7
10.5
13.1
3.7
3.5
1.9
357.4
6.5
3.2
4.6
4.5
0
2.2
a4
17.0
7.5
7.2
0
1.0
0.7
1.3
0
59.0
15.2
3.1
2.4
5.4
3.8
0
0.8
0
1.9
0
6.2
1.3
40.1
—
52.8
52.8
50.4(15)
11.0
568.1
10:33-1 1:03 AM
7.2
8.9
1Z9
4a7
65.9
40.9
4.6
19.6
13.0
14.0
14.7
0
1.4
7.5
4.2
7.8
1.6
5.7
0.7
5.8
4.1
1.3
1.8
0.4
292.6
7.3
2.8
4.3
4.7
0
22
3.1
7.3
5.6
6.0
0.3
0.8
0
1.3
0
45.8
14.8
2.5
2.0
5.4
2.5
0
0.9
0
1.0
0
1.3
1.3
31.7
—
4.8
4.8
12.9(5)
7.1
394.9
11:51-12:25PM
4.1
4.6
13.8
40.5
52.8
30.1
5.3
U2
8.0
8.7
8.4
0
Z7
3.5
2.6
3.0
1.3
21
0.7
6.1
3.0
0.5
0.6
0.3
212.7
1.0
1.9
3.7
3.7
0
1.4
2.3
6.7
5.3
5.4
0.3
0.4
0
1.0
0
33.0
5.9
0.9
0.7
2.3
1.1
0
0.6
0
0.5
0
0.9
0
12.8
19.8
19.8
10.7(8)
4.1
293.1
12:25-12:55 PM
23
8.2
30.1
121.8
153.5
86. 1
8.5
35.4
17.6
19.3
19.2
0
2.7
4.8
4.2
5.8
2.5
4.3
1.7
5.3
5.4
0.5
0.7
0.5
540.3
1.0
-
'11.9
9.4
a?
4.0
6.4
10.6
7.3
11.5
0
1.1
0
1.6
0
73.5
7.3
1.2
10
2.8
1.7
0
0.6
0
0.8
0
2.0
0.1
17.7
/
5.6
5.6
9.4(9)
3.0
649.5
Texaco Refinery
7-27-78
From N to NE. light
:30-1 :33 PM
33.8
95.5
86.9
175.2
53.8
46.4
5.2
15.8
4.9
12.3
19.5
0
9.0
4.8
25
6.5
3.1
6.3
4.6
9.0
16.0
2.9
4.0
0.5
618.3
5.9
27.5
15.7
7.5
5.9
1.8
2.4
4.8
4.6
3.7
0
0
0
0.4
0
80.2
14.3
4.6
2.8
9.9
5.8
0
0.7
0
0.8
0
3.6
0.5
43.1
—
6.9
6.9
15.8(8)
3.1
767.3
1:33-1 :35PM
73.5
189.8
236.7
342.7
113.1
81.7
6.4
39.8
21.7
32.4
36.5
0
14.8
10.3
9.0
15.4
7.7
17.1
10.3
21.4
36.5
5.1
6.9
2.9
1331.7
20.4
109.9
60.2
28.8
24.4
2.8
3.5
3.9
3.0
7.6
0
0
0
2.2
0
266.6
25.5
7.9
4.9
11.1
9.3
0
0.7
0
0.8
0
3.6
0.5
64.2
10.1
10.1
54.6(11)
7.7
1734.9
18
-------
Table 3. SUMMARY AND ANALYSIS OF TULSA HYDROCARBON DATA
< SP*
sot
LA*
2P/C2H2
SO/C2H2
2A/C2H2
ZNMHC/C2H2
%P from
vehicular
emissions
%O from
vehicular
emissions
' %Afrom
vehicular
emissions
% vehicular
% biogenic
(isoprene)
City -County
Health
Department
8:25 AM
150.6
21.6
39.0
17.9
2.6
4.6
34
38
127
84
50
0.5
City -County
Health
Department
8:55 AM
155.2
21.0
32.8
18.4
7.5
3.9
30
37
130
99
56
0.4
Post
Office
8:53 AM
357.4
59.0
40.1
32.4
5.3
3.6
51
21
61
107
33
0
Post
Office
10:33 AM
292.6
45.8
31.7
41.0
6.4
4.4
55
17
50
87
31
0
Liberty
Mounds
11:51 AM
212.7
33.0
12.8
52.1
8.1
3.1
72
13
40
123
24
0.1
Liberty
Mounds
12:25 PM
540.3
73.5
17.7
180.1
24.5
5.9
216
4
13
66
8
0
Texaco
Refinery
1 :30 PM
618.3
80.2
43.1
199.5
25.9
13.9
248
3
13
28
7
0
Texaco
Refinery
1 :33 PM
1331.7
266.6
64.2
172.5
34.5
8.3
225
4
9
47
8
0
VO
P = paraffins
0 = olefins
•^A = aromatics
-------
of hydrocarbons from Tulsa. The drop in contributions to the TNMHC burden
from vehicular sources between the two sampling vicinities implies an
increasing influence from other source(s), such as paraffins from the
refineries. No monoterpenes were detected in any of the samples and
only trace amounts of isoprene were found in four of the eight samples.
Since this study was performed, RTI has determined that the high
ethylene concentration observed at Liberty Mounds was due to sampling
echaust from their chemiluminescence ozone monitor (17). In addition,
isoprene and trans-2-pentene has been determined as having nearly identical
retention times on their GC column. Also, the large peaks identified as
isoprene were found to be due to column substrate deterioration. Consequently,
RTI has revised this downwind concentration to an average concentration
of 1.6 ppbC (Isoprene + trans-2-pentene).
RIO BLANCO COUNTY, COLORADO
In 1974, Occidental Oil and Ashland Oil established an air monitoring
station in the remote Piceance Creek Basin of Rio Blanco County, Colorado.
The station was instrumented to gather baseline data on the criteria
pollutants on a tract of federal land leased to the oil companies. In so
doing, the impact of future oil shale development operations on air quality
can be assessed. As of November 1977, however, only some surface excavation
and three access shafts have been started; the oil shale deposit has not yet
been reached by the access shafts.
Some activity is occurring at the other sites surrounding Cb, but no
large-scale operations have yet begun. Producing gas fields do exist nearby,
however.
The air quality data collected thus far are typical of remote background
concentrations of the criteria pollutants, with the exception of TNMHC.
Concentrations in the range of 4 to 7 ppmC have been observed. These values
seem inordinately high, not only for a remote area such as Cb, but even for
a poorly ventilated city such as Los Angeles. The monitoring station in
question has been audited by the U.S. Environmental Protection Agency (EPA),
Environmental Monitoring and Support Laboratory (EMSL) and has met per-
20
-------
formance specifications. Thus the frequent excursion of the TNMHC into
the ppmC range has remained a mystery. Occidental Oil has suggested that
the high levels may be caused by sage brush emissions, which are evidenced
by a characteristic camphor aroma. Others have suggested that the oil shale
deposit itself may be releasing volatile hydrocarbons.
In an attempt to provide some answers to these questions, air samples
were collected at the Cb tract for detailed hydrocarbon analysis. Samples
were collected in Tedlar bags on July 24 and 25, 1978 and shipped via air
express to Research Triangle Park, North Carolina for detailed analysis.
Samples were analyzed within 6 to 7 days after collection.
A total of six samples were collected at four sites. The sites are
identified in Figure 4.
Trailer 023 on tract Cb is the air monitoring station which has been
recording high hydrocarbon concentrations. At an elevation of 2115 m,
it is situated on a ridge about 1.6 km south of the oil shale surface
excavation activities. One sample was collected there at 12:50 pm on
July 24 (see table 4), and one sample at 10:05 am on July 25 (see Table 5).
Site SG-18 is approximately 4.5 km to the south of trailer 023 on the
same ridge but at a slightly higher elevation, 2249 m. Occidental Oil has
anticipated that this will be the future site of the air monitoring station
now at trailer 023. One sample was collected on July 24 at Site SG-18.
Since surface winds were out of the south on July 24, this sample was
representative of the air passing over Cb.
Trailer 020 lies in a valley about 4.3 km north of trailer 023.
Though a monitoring station exists at Site 020, TNMHC was not measured. Two
samples were collected at Site 020; one was taken at 3:27 pm on July 24 and
one at 9:03 am on July 25. The last sample collected on July 24 was taken
downwind of the Mobile Oil natural gas processing facility at Piceance
Creek. Although during the sampling period this site was downwind of Cb,
it was hoped that the hydrocarbon distribution from this facility would serve
as a possible identifying fingerprint to natural gas emissions in the area.
The Mobil gas field lies about 10 km NNE of Site 023.
21
-------
Table 4. HYDROCARBON COMPOSITION OF RIO BLANCO COUNTY, COLORADO AIR
Location:
"Date;
Wind: ' ~
Compound
Paraffins
ethane
propane
isobutane
n-butane
isopentane
n-pentane
cyclopentane
2-methylpentane
3-methylpentane
n-hexane
2.4-dimethvlpentane
methylcyclopentane
cyclohexane
2-methylhexane
2,3-dimethylpemane
3-methylhexane
cis-1 ,3-dimethylcycIopentane
2,2,4-trimethylpentane
trans- 1 ,3-dimethylcyclopentane
n-heptane
methylcyclohexane
nonane
decane
undecane
1 paraffins
Olefins
ethylene
propylene
isobutylene
trans- 2-butene
cis-2-butene/butadiene
1-pentene
2-methyl-1-butene
trans-2-pentene
cis-2-pentene
2-methy1-2-butene
isoprene
4-methyl-2-pentene
1 -hexene
trans-2-hexane
cis-2-hexene
1 olefins
Aromatics
toluene
ethylbenzene
p-xylene
m-xylene
o-xylene
isopropylbenzene
n-propylbenzene
m+p-ethyltoluene
1 ,3,5-trimethylbenzene
o-ethvltoluene
1 ,2,4-trimethy Ibenzene
m-ethyltoluene
1 aromatics
Oxygenates
acetaldehyde
acetone
1 oxygenates
i; Unknown gc peaks (N)
Acetylene
Total NMHC
Trailer 023
Twrs, —
Var. S to N
SiteSG-18
7-24-78
S
Trailer 020
7-24-78
E (up valley)
Mobil Natural
Gas Facility
7-24-78
S (downwind)
Time
12:55-12:55 PM
5.8
3.2
0.5
1.4
Z3
2.0
1.5
2.3
3.7
3.2
3.9
0
0.6
4.1
1.7
5.5
0
0
13.1
3.5
0
1.7
3.6
2.3
65.9
25.5
2.8
0
0
0
0.3
0.7
0
1.7
1.8
0.1
0.2
0.3
0.2
0
33.5
10.9
2.2
2.0
4.2
3.6
0
1.6
0
3.0
0
10.9
3.8
42.2
9.4
23.7
33.1
77.9(24)
3.1
255.7
1:43-1 :50 PM
5.4
3.9
1.6
1.0
1.5
1.6
1.0
2.5
1.6
1.7
4.1
0
0.6
2.3
0.7
2.3
0
0
6.6
1.4
0.5
0.7
1.7
3:27-3:31 PM
4.6
6.3
0.6
1.5
2.1
9.7
0.5
1.3
0.9
1.1
0
2.4
0.1
1.7
0.6
2.1
0
9.3
1.4
0.6
2.0
0.3
1.3
1.2 ! 0.8
43.6
1.3
1.2
0
0
0
0.2
1.2
0
0
1.7
1.8
0
0.5
0
0
7.8
7.4
1.1
1.2
2.0
3.2
1.7
0.8
0
2.0
0
6.0
0.4
25.8
7.8
18.0
25.8
24.1(12)
2.7
129.8
51.0
1.2
1.0
0
0
0
0
0.7
0
0
2.4
5.6
0.2
1.1
0.2
0
12.3
5.0
1.0
0.8
1.3
2.2
0
0.5
0
0.9
0
3.2
0.3
15.3
6.2
16.7
22.9
13.6(14)
1.9
1170
4:01-4:11 PM
136.1
465.3
3.4
56.0
79.3
6R2
9.3
49.5
27.1
58.8
37.4
0
31.9
23.4
ao
27.3
11.2
16.6
0
50.7
87.0
8.8
5.4
1.6
1261.0
2.6
1.0
5.4
1.6
3.5
0.8
10.7
-
0
0
0
0
0
25.4
17.5
3.6
1.8
5.1
3.6
0
0.8
0
1.6
0
3.8
4.8
42.7
16.9
16.9
158.6(34)
3.2
1508.8
Trailer 020
7-25-78
E toNE
9:03-9:08 AM
5.1
5.7
1.3
0.7
2.0
1.3
1.3
0.8
0.7
1.0
1.6
0
0.2
0.7
0.2
1.3
0
5.3
1.4
1.4
1.9
1.4
1.7
1.1
37.9
1.3
0.5
0
0
0
0
0.7
0
0
3.0
3.9
0
0
0
9.4
5.3
0.8
0.9
1.6
3.3
0
0.8
0
1.4
0
6.5
5.3
25.8
5.2
5.1
10.4
35.5(22)
1.4
120.3
Trailer 023
7-25-78
S
10:05-10:10 AM
4.9
5.3
1.1
1.4
2.2
2.6
0.5
1.3
1.4
1.0
1.9
0
0.4
1.7
1.7
1.6
0
0
7.5
1.4
1.4
0.2
1.6
2.5
42.3
1.4
0.9
0
0
0
0.2
0.4
0
0
0.9
0.9
-
0.1
0
0
4.7
4.8
0.9
2.0
0
2.9
0
0.7
0
1.3
0
4.4
5.3
22.4
5.4
11.8
17.1
49.3(22)
2.4
138.1
22
-------
Table 5. SUMMARY AND ANALYSIS OF RIO BLANCO, COLORADO HYDROCARBON DATA
Site:
Date:
Time:
SP
20
2A
2P/C2H2
SO/C2H2
2A/C2H2
SNMHC/C2H2
% vehicular
emissions
% biogenic
(isoprene)
023
July 24
12:50 AM
66.1
33.3
42.2
21.2
10.7
13.5
82.0
21
0
18
July 24
1 :43 PM
43.6
7.8
25.8
16.5
2.9
9.7
49.0
35
1
020
July 24
3:27 PM
51.0
12.3
15.3
26.4
6.4
7.9
60.6
28
5
Mobil Gas
July 24
4:01 PM
1262.0
25.4
42.7
389.5
7.9
13.2
465.7
4
0
020
July 25
9:03 AM
37.9
9.4
25.8
27.7
2.9
8.0
87.8
20
3
023
July 25
10:05 AM
42.3
4.7
22.4
17.6
1.5
6.9
57.3
30
1
Tunnel
samples
(17)
-
-
-
6.8
3.2
3.9
17
100
-
23
-------
In general, the absolute levels of TNMHC were low. With the
exception of the sample from Site 023 on July 24, the samples ranged from
117 to 118 ppbC at Site SG-18, trailer 023 and trailer 020. Apparently,
the lone sample above this range was contaminated by the evaporative
emissions/exhaust from the vehicles parked in close proximity, and by
ethylene exhaust from the ozone monitor. As was noted at the time of
sample collection the wind shifted when this was being collected resulting
in the collection of air that had passed over the monitoring trailer. This
was not a problem in subsequent samples.
In order to estimate what portion of the TNMHC was due to vehicular
emissions alone, the technique of Lonneman et al. (18) was again employed.
This method uses acetylene as a normalizing compound to estimate the con-
tribution of auto exhaust to the hydrocarbon burden. An implicit assumption
is that acetylene is emitted in significant concentrations only by the
combustion process of autos, and that under normal operating conditions
automobiles will also emit a number of paraffins, olefins, and aromatics
in proportion to acetylene. The limitations of this method are described
by Lonneman et al. (18).
Normalization of TNMHC and the individual groups (paraffins, olefins,
aromatics) to acetylene is shown in Table 5. As is evident, only 20 to
35% of the hydrocarbons are directly attributable to tailpipe emissions.
But as Lonneman demonstrated, in industrialized areas, the contribution of
auto exhaust may be very high during morning rush hour traffic yet at later
times and under different meteorological conditions, other significant
hydrocarbon sources may exist: industrial emissions, carburetor evaporative
emissions, and gasoline spillage. Consequently, in a remote area such as
Cb, an urban plume would appear as a photochemically-exhausted, well-mixed
air mass containing mostly lesser reactive paraffins and some aromatics.
The exact distribution would depend on the emission characteristicis of the
urban area as well as the transport time period of the urban plume.
Biogenic hydrocarbons do not seem to be present in significant concen-
trations at Cb. Isoprene was not seen at more than 5.6 ppbC; nonetheless,
this compound was the most prominant olefin in half of the samples (exclusive
24
-------
of the Mobil gas facility). The monoterpenes that are known to be
emitted by sage brush (19) were not seen. (It should be noted, however,
that the major sage volatile, camphor, has not been run through ESRL sampling
and analytical procedures to determine if our GC system would see this
component-camphor is a high boiling oxygenate.) The other identified sage
volatiles will be determined by our system if present, including: 1,8-
cineol, alpha-pinene, beta-pinene, camphene, limonene, cymene, myrcene,
beta-phellendrene, and y-terpinene. Also of note is that if the reported
high hydrocarbon concentrations are due to the terpenic emissions of
sage, then an inverse relationship should be seen between ozone and TNMHC
in an NO -defficient atmosphere. At ppm concentrations, the highly reactive
A
terpenes will react with ambient ozone very quickly. Such observations were
not observed (LaHue, personal communication). The C~-C- paraffins, however,
could coexist with ozone since their reaction is very slow.
A closer examination of the hydrocarbon distribution reveals that
paraffin to C~H_ ratio is particularly high; this seems to be caused by
relatively high concentrations of the C» to C,. paraffins. Either the makeup
of the incoming air mass (as noted previously) or local natural gas emissions
could be the source of the high concentrations. Though the downwind sample of
the Mobil Piceance Creek Gas Field shows elevated levels of the C_ to C,.
paraffins, it is not possible to determine from this small sampling effort
which of these sources may be more significant. The total hydrocarbon
analyzer was not operating in the methane mode during our visit. It read
only 2.0 ppmC total hydrocarbon (THC) on July 24, and 1.6 ppmC THC on July
25. These readings are not grossly inconsistent with the detailed analyses
presented here, assuming a background of methane of about 1.5 to 1.6 ppm.
Since the high TNMHC reported at Cb do not seem to correlate with
meteorological parameters of season (Lahue, personal communication), or
display an inverse relationship to ozone, biogenic emissions and transport
from distant urban areas seem unlikely explanations of this phenomenon.
The hydrocarbon distribution suggests a greater than usual presence of
lighter paraffins due possibly to the local emissions of gas fields.
However, if such were the case, then some correlation should be observed with
wind direction or mixing heights.
25
-------
It is the opinion of these investigators that the previously reported
high values are possibly due to a malfunctioning hydrocarbon analyzer, or
more likely, to sampling of ethylene used for the ozone monitor. Ethylene
contamination is frequently encountered around such monitors. Monitors
must be equipped with catalytic combustors to destroy ethylene in the
exhaust, and the ethylene feed system plumbing must be thoroughly checked
for leaks (i.e., regulator fittings, diaphragms, fittings in the instrument).
Ethylene contamination from the monitoring station was suggested in the
July 24 trailer 023 sample since shifting winds caused station backwash to
be sampled.
GREAT SMOKY MOUNTAINS NATIONAL PARK, TENNESSEE
When the issue of natural organic emissions was first discussed by
Went (2), the blue haze that gives the Smoky Mountains their name was proposed
to be caused by the oxidation of terpenes to aerosols. However, no attempts
to measure ambient terpene concentrations in the Smokies have been reported.
Hence, a 2-day sampling effort was undertaken to determine the hydrocarbon
composition of Smoky Mountain air.
The results of the analyses are shown in Table 6. To determine the
auto exhaust contribution, the data have been normalized to acetylene as
described previously (Table 7). This procedure yields vehicular contributions
to the samples ranging from 38 to 119%. It is likely that some of these
samples were influenced by acetylene source(s) other than auto exhaust,
since the procedure as a sole tracer for this source yields contributions
greater than 100%. Campfires at a nearby campground were also probable
sources of the compound, since acetylene has been identified as a major
component of the incomplete combustion of wood and plant matter (20).
The concentrations of TNMHC averaged quite low. With the exception
of two of nine samples, which were probably influenced by early morning
vehicular traffic and smoldering campfires, the concentrations ranged from
87 to 114 ppbC. Isoprene was the dominant olefin in three of the nine
samples, but was not higher than 6 ppbC. The combined contribution of the
biogenic hydrocarbons isoprene and alpha-pinene to the TNMHC in all samples
was at least 1%, but no higher than 6%. Of note is that alpha-pinene and
26
-------
Table 6. HYDROCARBON COMPOSITION OF SMOKY MOUNTAIN AIR
Date:
Compound
Paraffins
ethane
propane
isobutane
n-butane
isopentane
n-pentane
cyclopentane
2-methylpentane
3-methylpentane
n-hexane
2.4-dimethylpemane
melhylcyclopentane
cvclohexane
2-methylhexBne
2.3-dimethylpentane
3-methylhexane
cis-1.3-dimethylcyclopemane
2.2,4-trimethylpentane
trans-1 ,3-dimethylcvclopentane
n-heptane
methylcyclohexane
nonane
decane
1 paraffins
Olefins
ethylene
propylene
nobutylene
trans-2-butene
cis-2-buterie/butadiene
1-pentene
2-melhyl-l -butene
trans-2-pentene
cis-2-pemene
2-methyl-2-butene
isoprene
4-*methyl-2-pemene
1-hexene
trans-2-hexene
cis-2-hexene
Z olefins
Aromatics
benzene
toluene
ethylbenzene
p-xylene/a-pinene
m-xylene
o-xylene
isopropylbenzene
n-propylbenzene
m+p-ethyltoluene
1 ,3.5-trimethylbenzene
o-ethyltoluene
1 aromatics
Oxygenates
acetaldehyde
acetone
1 oxygenates
~ unknown gc peaks (N)
acetylene
Total NMHC
9-25-78
9-25-78
9-25-78
9-25-78
9-25-78
9-26-78
9-26-78 1 9-26-78
9-26-78
Time
6:00-8:00 AM
10.2
9.2
2.7
3.8
4.5
3.3
a?
1.5
1.0
1.0
0
1.2
1.0
10:00-10:20 AM
9.4
5.8
2.3
5.1
5.6
4.0
1.1
2.7
1.4
1.8
0
1.S
0.8
3.2 1.8
1.3
0.6
1.0
0
0
as
0
0.5
0.4
47.4
2.0
0.4
-
0.7
0
1.1
1.1
0.3
0
0
-
0
0
0
0
6.6
16
2.1
0.9
2.4
0.7
0.3
0.7
0
0
0
0
10.9
4.1
7.8
11.9
17(9)
£8
87.4
1.0
1.0
0.4
0.9
0.2
as
0.9
0.6
0.3
49.3
5.6
1.7
-
as
0
0.3
0.5
0
0
0
4.2
-
0
0
0
12.8
5.5
5.1
1.0
1.2
2.0
1.1
0
0
1.1
0.5
a?
mo
4.0
4.4
R4
10.7(9)
4.8
104.0
12:00-12:15 PM
11.7
7.9
2.0
4.0
3.2
1.9
0.4
1.0
a?
0.7
0
1.2
0.1
0.2
0.1
0.2
0
0
0
0
0
0.2
0.6
36.1
1.4
0.9
_
0.8
0
0
0.1
0
0
0
3.5
_
0
0
0
6.7
7.9
3.5
as
0.8
0.9
0.5
0.3
0
0
-
0.6
15.0
4.3
11.6
15.8
17.4(9)
Z5
93.6
2:15-2:45 PM
16.0
&4
2.2
4.6
3.7
2.6
0.4
1.1
0.7
0.8
0
0
0
0
0.5
0.1
0.4
0.8
0.4
a?
0
0.8
0.6
44.8
3.2
1.0
-
0.8
0.4
0.3
0
0
0.3
0.4
5.7
..
0
0
0
12.0
3.6
3.6
0.6
0.9
0.8
a?
0
0
0
0
0.6
10.8
4.7
12.0
16.7
14.6(8)
3.2
102.1
4:00-4:20PM
11.3
7.3
1.7
3.6
3.0
0.4
0.9
0.8
0.7
0
0.6
as
0
0
0
0.3
0
0
0
0.3
0.9
1.7
0.9
35.0
1.4
as
_
0.7
0
0
0
0
0
0.1
4.9
_
0
0
0
7.6
6.8
16.6
1.1
1.4
3.0
1.3
0
0.4
1.1
0.5
1.0
33.1
3.1
a3
11.4
24.7(16)
2.6
114.4
8:25-8:27 AM
15.9
13.3
5.5
7.6
6.9
4.1
1.7
4.3
11
2.4
0
2.1
1.2
1.3
0.9
1.6
0.9
0.7
0
0.4
0.6
0.5
0.4
75.5
7.4
8.0
_
1.5
0
0.5
0.4
0.8
0
0
4.4
0.5
0.3
0
23.7
7.6
7.9
1.5
2.5
2.6
1.4
0.6
0.6
1.4
0
0
26.1
13.3
9.8
23.1
16.9(12)
6.0
171.3
8:30-8:34 AM
10.7
11.3
2.5
5.5
6.4
4.0
1.6
10:00-10:20 AM
as
5.4
1.9
4.4
5.2
11:30-1 1:35 AM
&6
5.0
2.1
4.6
5.3
2.8 33
0.9 0.7
4.1 2.4 2.2
2.4 1.1 1.0
2.6
0
1.6
1.2
2.4
1.1
2.0
0.3
0.8
0.3
1.1
1.0
0.6
0.8
64.1
4.7
2.5
-
0.7
0.5
0.4
0.4
as
3.8
3.7
0.7
..
0.3
0.3
0
18.8
7.0
7.8
0.9
2.2
2.3
1.3
0.3
0.4
1.3
0.8
0
24.2
9.7
9.7
19.0(16)
6.2
143.3
1.2 1.5
0 0
1.1 0
0 0
1.4 0
0.7 0.5
1.2 1.3
0 0.8
0.8 0.6
0 0
0.6 0.9
0 0.5
0.6 0.6
0.9 0.4
41.5 39.8
5.6 7.2
1.7 3.3
-
0.8 0.9
0.6 0
0.3 0
0.3 . 0
0.5 0
0
0
3.6
„
0
0
0
13.3
0.6
6.9
1.0
1.6
2.1
1.2
0
0
1.0
0.7
0.6
25.6
3.5
4.2
7.8
12.9(101
7.5
ioas
0
0
0
_
0
0
0
11.2
5.7
6.7
1.2
1.2
2.1
1.1
0
0
1.0
0.4
0.3
19.8
8.1
2.1
10.7
17.4(11)
7.4
106.2
2.7
-------
Table 7. SUMMARY AND ANALYSIS OF SMOKY MOUNTAIN HYDROCARBON DATA
Time:
ZP
ZO
SA
2P/C2H2
SO/C2H2
1A/C2H2
1NMHC/C2H2
% vehicular emissions
% biogenic emissions
9-25-78
6:00 AM
47.4
5.6
10.9
17.1
2.0
3.9
31.6
54
3
9-25-78
10:00 AM
49.3
12.8
18.0
10.3
2.7
3.7
21.7
78
5
9-25-78
12:OOPM
36.1
6.7
15.0
14.3
2.7
5.9
37.0
46
5
9-25-78
2:15 PM
44.8
12.0
10.8
14.0
3.8
3.4
31.9
53
6
9-25-78
4:00 PM
35.0
7.6
33.1
13.5
2.9
12.8
44.2
38
6
9-26-78
8:25 AM
75.5
23.7
26.1
12.5
3.9
4.3
28.5
60
4
9-26-78
8:30 AM
64.1
18.8
24.2
10.5
3.1
4.2
23.4
73
2
9-26-78
10:00 AM
41.5
13.3
25.6
5.6
1.8
3.4
14.5
117
5
9-26-78
1 1 :30 AM
39.8
11.2
19.8
5.4
1.5
2.7
14.3
119
1
28
-------
p-xylene were unresolved in this series of samples (due to GC modifications)
and therefore may be biased high. Nevertheless, even a 6% biogenic con-
tribution to the observed low concentrations of TNMHC is small, considering
the sampling proximity to one of the most diverse, densely vegetated areas
in the United States. An important contributine factor to the Smoky
Mountains lush vegetation is the high rainfall that often exceeds 90 inches
per year; this amount is second only to the Pacific Northwest in the United
States. Thus the argument furthered by Sandberg et al. (21) that a direct
correlation should exist between an active growing season and high biogenic
hydrocarbon concentrations is not supported in the Smokies. That the low
vegetative density of the San Francisco Bay area could produce hydrocarbon
levels greater than the Smokies seems therefore unlikely.
29
-------
REFERENCES
1. Went, F.W. Organic Matter in the Atmosphere, and Its Possible
Relation to Petroleum Formation. Proceedings of the National Academy of
Sciences 46, pp. 212-221, 1960.
2. Went, F.W. Blue Hazes in the Atmosphere. Nature 187, pp. 641-643, 1960.
3. Rasmussen, R.A. and F.W. Went. Volatile Organic Material of Plant Origin
in the Atmosphere. Proceedings of the National Academy of Sciences -53,
pp. 215-220, 1965.
4. Ripperton, L.A. , 0. White, and H.E. Jeffries. Gas Phase Ozone-Pinene
Reactions. Division of Air, Water, and Waste Chemistry, 147th National
Meeting American Chemical Society, Chicago, Illinois, pp. 54-56, Sept-.
ember 1967-
5. Robinson, E. and R. C. Robbins. Sources, Abundance, and Fate of Gaseous
Atmospheric Pollutants. Report SRI Project PR-6755, Stanford Research
Institute, pp. 1-122, 1968.
6. Reckner, L.R. Survey of the EPA-Reference Method for measurement of
Non-methane Hydrocarbons in Ambient Air. U.S. Environmental Protection
Agency, EPA-650/4-75-008, pp. 1-42, 1974.
7. McElroy, F.F. and V.L. Thompson. Hydrocarbon Measurement Discrepancies
Among Various Analyzers Using Flame-Ionization Detectors. U.S.
Environmental Protection Agency, EPA-600/4-75-010, pp. 1-26, 1975.
8. Rasmussen, R.A., R.B. Chatfield, M.W. Holdren, and E. Robinson. Hydro-
carbon Levels in a Midwest Open-Forested Area. Draft Report submitted
to the Coordinating Research Council, October 1976.
9. Lonneman, W.A., R. L. Seila, and S.A. Meeks, Preliminary Results of
- Hydrocarbon and Other Pollutant Measurements Taken During the 1975
Northeast Oxidant Transport Study. Proceedings of Symposium on 1975
Northeast Oxidant Transport Study, EPA-600/3-77-017, pp. 547-549, 1975.
10. Whitby, R.A. and P.E. Coffey. Measurement of Terpenes and Other
Organics in an Adirondack Mountain Pine Forest. Journal of Geophysical
Research 82, pp. 5928-5934, 1977.
11. Lonneman, W.A. , R.L. Seila, and J. J. Bufalini. Ambient Air Hydrocarbon
Concentrations in Florida. Environmental Science and Technology 12,
pp. 459-463, 1978.
30
-------
12. Schjoldager, J. and B. M. Wathne. Preliminary Study of Hydrocarbons
in Forests. Norsk Institute for Luftforskning, pp. 1-26, 1978.
13. Seila, R.L., W.A. Lonneman, and S.A. Meeks. Evaluation of Polyvinyl
Fluoride as a Container Material for Air Pollution Samples. Journal
of Environmental Science and Health-Environmental, Science and Engineering
All (2), pp. 121-130, 1976.
14. Seila, R.L. Non-Urban Hydrocarbon Concentrations in the Ambient Air
North of Houston, Texas. U.S. Environmental Protection Agency, EPA-600/
3-79-010, February 1979.
15. Holdren, M.W., H.H. Westberg, and P.R. Zimmerman. Analysis of Mono-
terpene Hydrocarbons in Rural Atmospheres. Unpublished manuscript,
Washington State University.
16. Research Triangle Institute. Study of the Nature of Ozone, Oxides of
Nitrogen, and Non-methane Hydrocarbons in Tulsa, Oklahoma. Draft Report
EPA Contract No. 68-02-2808, 1978.
17. Research Triangle Institute. Study of the Nature of Ozone, Oxides of
Nitrogen, and Non-methane Hydrocarbons in Tulsa, Oklahoma. Volume II.
Data Tabulation. U.S. Environmental Protection Agency, EPA-450/4-79-008b,
1979.
18. Lonneman, W.A., S.L. Kopczynski, P.E. Darley, and F.D. Dutterfield.
Hydrocarbon composition of Urban Air Pollution. Environmental Science
and Technology 8>, pp. 229-236, 1974.
19. Tyson, B.J., W.A. Dement, and H.A. Mooney. Volatilisation of Terpenes
from Salvia Mellifera. Nature 252. pp. 119-120, 1974.
20. Sandberg, D.V., S.G. Pickford, and E.F. Darley. Emissions from Slash
Burning and the Influence of Flame Retardant Chemicals. Journal of
the Mr Pollution Control Association 25, pp. 278-281, 1975.
21. Sandberg, J.S., M.J. Basso, and B.A. Oakin. Winter Rain and Summer
Ozone; A Predictive Relationship. Science 200, pp. 1051-1054, 1978.
31
-------
TECHNICAL REPORT DATA
(Please read Instructions on the reverse before completing)
"£^688/3-80-023
4. TITLE AND SUBTITLE BIUGEN1C HYDROCARBON CONTRIBUTION TO
THE AMBIENT AIR OF SELECTED AREAS
Tulsa; Great Smoky Mountains; Rio Blanco County,
Colorado
3. RECIPIENT'S ACCESSION-NO.
5. REPORT DATE
January 1980
6. PERFORMING ORGANIZATION CODE
. AUTHOR(S)
Robert R. Arnts and Sarah A. Meeks
8. PERFORMING ORGANIZATION REPORT NO.
PERFORMING ORGANIZATION NAME AND ADDRESS
Same as block 12
10. PROGRAM ELEMENT NO.
A05A1A 02-0011 (FY-8C)
11. CONTRACT/GRANT NO.
12. SPONSORING AGENCY NAME AND ADDRESS
Environmental Sciences Research Laboratory-RTF, NC
Office of Research and Development
U.S. Environmental Protection Agency
Research Triangle Park. North Carol -ina 97711
13. TYPE OF REPORT AND PERIOD COVERED
In-house
14. SPONSORING AGENCY CODE
EPA/600/09
15. SUPPLEMENTARY NOTES
16. ABSTRACT • " "" ~ '
A critical review of the literature reveals nonmethane hydrocarbons in rural
u rfm°te.areas consist ^inly of anthropogenic species, and are composed of less
than IQt biogenically-related compounds (i.e., monoterpenes and isoprene). Despite
these results, some investigators continue to invoke "natural hydrocarbon emissions"
to explain naturally occurring haze, incorrectly identified gas chromatographic peaks
and high concentrations of total nonmethane hydrocarbons that are measured by
indiscriminate (total hydrocarbon-methane) analyzers. In response to the suggestion
that biogenic emissions are responsible for the high hydrocarbon concentrations
described in several reports, the Environmental Sciences Research Laboratory of the
U.S. Environmental Protection Agency initiated short-term sampling as a means of
validation. A limited number of whole-air samples were collected in Tedlar bags
and analyzed by gas chromatography with flame ionization detection. The areas of
study included: Tulsa, Oklahoma; Rio Blanco County, Colorado; and the Great Smoky
Mountains in Tennessee. Tulsa air was found to contain an average of 0.2% isoprene
of the total nonmethane hydrocarbon load. Rio Blanco County and the Smoky Mountain
air, respectively, averaged about 2% and 4% biogenic hydrocarbon of the total
non-methane hydrocarbon loads. Isoprene appears to be a dominant olefin in rural and
remote areas.
17.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b.lDENTIFIERS/OPEN ENDED TERMS C. COS AT I Field/Group
* Air pollution
* Hydrocarbons
* Biological productivity
* Chemical analysis
Gas chromatography
Tulsa, OK
Great Smoky Mountains
Rio Blanco Co., Colorado
13B
07C
08A
07D
18. DISTRIBUTION STATEMENT
RELEASE TO PUBLIC
19. SECURITY CLASS (ThisReport)
UNCT.ASSTFTF.r>
21. NO. OF PAGES
40
20. SECURITY CLASS (Thispage)
UNCLASSIFIED
22. PRICE
EPA Form 2220-1 (9-73)
32
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