WATER POLLUTION CONTROL RESEARCH SERIES
16020 GAG 02/71
SAMPLING OF
GLACIAL SNOW FOR PESTICIDE ANALYSIS
U.S. ENVIRONMENTAL PROTECTION AGENCY
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The. Water Pollution Control Research Series describes the
results and progress in the control and abatement of
pollution in our Nation's waters. They provide a central
source of information on the research, development, and
demonstration activities in the water research program
of the Environmental Protection Agency, through* inhbuce
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organizations.
Inquiries pertaining to Water Pollution Control Research
Reports should be directed to the Chief, Publications
Branch (Water), Research Information Division, RSH,
Environmental Protection Agency, Washington, D.C, 20460.
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SAMPLING OF GLACIAL SNOW FOR PESTICIDE ANALYSIS
by
Thomas R. Stengle
Department of Chemistry
University of Massachusetts
Amherst, Massachusetts 01002
James J. Lichtenberg
Analytical Quality Control Laboratory
Water Quality Office
Environmental Protection Agency
1014 Broadway, Cincinnati, Ohio 45202
Charles S. Houston
Department of Community Medicine
College of Medicine
The University of Vermont
Burlington, Vermont 05401
for the
Office of Research and Monitoring
ENVIRONMENTAL PROTECTION AGENCY
Project #16020 GAG
February 1971
For sale by the Superintendent of Documents, U.S. Government Printing Office, Washington, D.C., 20402 - Price 38 cents
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EPA Review Notice
This report has been revieved by the Environmental Protection
Agency and approved for publication. Approval does not
signify that the contents necessarily reflect the views and
policies of the Environmental Protection Agency nor does
mention of trade names or commercial products constitute
endorsement or recommendation for use.
ii
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ABSTRACT
This project was intended to demonstrate the feasibility of
taking snow samples from high altitude snowfields for pesti-
cide analysis, and to develop sampling techniques which
would avoid contamination. The sampling was to be carried
out in the field, under adverse conditions, with minimal
equipment, Coincidentally, the DDT level in the sampling
site could be determined.
The sampling was done on the plateau glacier (elevation
17,500 ft.) of Mt. Logan, Y.T., Canada. The area is remote
from civilization, and the sampling team had to contend
with storms, low temperatures, and the effects of high alti-
tude. Simple techniques for obtaining samples and shipping
them to the laboratory were tested. Samples were taken to
a depth of 15 meters to determine whether DDT concentration
varied with the age of the snow.
Analysis showed no DDT within the limit of detectability.
However, over half the samples were contaminated with PCB's
which raised the detectability limit to 10-50 ng/1. The
limit was 5 ng/1 for the uncontaminated samples. The PCB
contamination is believed to have come from the sampling
auger, as an analysis of rinsings from it seems to confirm.
It is recommended that more attention be paid to precleaning
the sampling equipment in future work.
This report was submitted in fulfillment of project
# 16020 GAG under the partial sponsorship of the Water
Quality Office of the Environmental Protection Agency.
iii
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CONTENTS
Section
I Conclusions
II Recommendations
III Introduction
IV Preparations for Field Work
V . Sampling
VI Analysis
VII Acknowledgments
VIII References
1
3
5
7
11
15
21
23
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TABLES
Number Page
I Collection Data and Analytical
Results for Snow Samples 13
II Results of Trace Metal Analysis
vi
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SECTION I
CONCLUSIONS
It is highly likely that the plateau glacier (elevation
17,500 ft.) on Mt. Logan, Y.T., Canada is free of contamina-
tion by DDT within the limit of detectability. The results
of this study are equivocal, since some snow samples were
contaminated with polychlorinated biphenyls, which mask the
presence, if any, of DDT.
Samples of snow which fell many years ago can readily
be obtained from glaciers, although the sampling must often
be done in remote areas under adverse conditions. The
samples are suitable for pesticide analysis if the sampling
equipment is well cleaned in advance, and if certain pre-
cautions are followed. Sampling for trace metals is more
difficult, and cannot be accomplished successfully without
elaborate planning and sophisticated procedures.
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SECTION II
RECOMMENDATIONS
The results of this study were clouded because of
contamination of some of the snow samples with PCB's.
This presumably came from the auger used for sampling. It
is recommended that this work be repeated on a limited
scale with careful precleaning of the equipment in order to
remove this uncertainty.
In future snow sampling the techniques developed in
this work can be recommended as reliable, inexpensive, and
simple to apply in the field.
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SECTION III
INTRODUCTION
Since its introduction a generation ago, enormous
quantities of DDT have been used in a variety of pesticidial
formulations. Pears have recently been aroused that much of
the world has been polluted by residues of this non-biode-
gradable material* It is commonly found in surface water,
and in many animals such as cattle, fish, and even humans.
The extent of this contamination is not clear. It could be
limited to certain well-defined pathways which lead from
the original application of the material through a known
chain of dilutions (with concentration points such as animal
fat along the way) to eventual dissipation into concentra-
tions too small to be detected. On the other hand the
material could be so widespread that it has become a signif-
icant constituent of major portions of the earth, e.jg., the
atmosphere or the oceans. ~
Although the use of DDT as a pesticide is being phased
out, the answers to such questions are important, for the
DDT system can serve as a paradigm for other forms of wide-
spread pollution, past and to come. In fact, DDT is an
excellent substance for a model study. It is strictly a
synthetic chemical, and there is no natural background
level. Since it is not biodegradable, its presence can be
detected long after it has been applied. Several labora-
tories have developed analytical techniques of great sensi-
tivity for the material. Finally, as the use of DDT is
phased out, its dissipation can be observed. Thus, DDT is
an ideal material to study both for determining the present
state of world pollution and to observe the rate of de-
pollution as its use is discontinued.
All of the world's fresh water is ultimately traceable
to the atmosphere. It is of considerable importance to
determine if there are contaminants in the atmosphere which
can be carried down in precipitation. The sampling of
glacial snow is an intriguing approach to the problem, for
it can yield data on both the present and the past condition
of the atmosphere. In many glaciers snow falls from a
hundred years past lie over one another; one need only bore
down from the surface to sample the snow of past years.
This project is an attempt to ascertain the feasibility of
sampling erlacial snow in the field with minimal equipment,
under adverse conditions.
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SECTION IV
PREPARATIONS FOR FIELD WORK
The success of field work is entirely dependent on
careful preparation. This is particularly true when the
site is a glacier, for the season is short, and one is often
far from civilization. It may be impossible to procure an
overlooked item or repair malfunctioning equipment. In this
project careful preparation was especially important, since
the sampling site was very remote, and the prevailing condi-
tions were quite hostile.
The site chosen for this work was the high plateau
glacier on Mt. Logan at an elevation of 17,500 ft. For
several years the Arctic Institute of North America has
operated a high altitude research facility at this point
during the summer season. The DDT sampling was easy to add
on to that laboratory's projects, because the A.I.N.A.'s
personnel have the equipment and experience necessary for
obtaining snow samples at depth in glaciers.
Mt. Logan lies near the center of the St. Elias range
in the Yukon Territory of Canada. It is about twenty miles
east of the Alaska-Yukon boundary, and forty miles north of
the Gulf of Alaska. Mt. Logan is remote from the outposts
of civilization, as it is surrounded by one of the world's
most heavily glaciated areas. The nearest permanent human
habitation or road is nearly ninety miles away. Due to the
short growing season, practically no agriculture is practiced
in the Yukon, and massive applications of pesticides are
unknown there.
In terms of sheer bulk, Logan is said to be the
largest mountain in the world. The lower section is a mas-
sive rock, roughly ten miles long by four miles wide which
culminates in a plateau at 17,500 ft. The plateau is
circled by a range of seven peaks, all over 18,000 ft. The
principal summit reaches to 19,850 ft. This plateau is the
most favorable spot in North America for a high altitude
laboratory. It is sheltered from the worst of the high
mountain weather, and is readily accessible to ski-equipped
aircraft. Less than an hour's flying time away, the Arctic
Institute maintains a permanent base and an airstrip on the
shore of Kluane Lake at 2,600 ft. elevation. This delight-
ful spot is on the Alaska Highway just 150 miles north of
the city of Whitehorse, the capital of the Yukon Territory.
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Supplies for the Mt. Logan site are trucked from Whitehorse
to Kluane and. then flown onto the mountain by ski plane.
For collecting the snow samples, the Arctic Institute
purchased a new SIPRE auger with 30 meters of extension
rods. In addition another auger was borrowed from the U.S.
Army Cold Regions Research and Engineering Laboratory at
Hanover, New Hampshire to serve as a backup in case the
first instrument was lost or damaged. This device was
designed specifically for sampling of snow and ice by the
Snow, Ice, and Permafrost Research Establishment. It
consists of a barrel with a bore of three inches and a
length of one meter. One end is fitted with cutting blades,
and the other is attached to a tee-bar handle for turning.
It is constructed of stainless steel and coated with Teflon.
The cutting blades are of tool steel. In use, the auger is
turned by hand using the tee-bar. As the bore hole becomes
deeper, extension rods are attached between the auger and
the handle. These are one meter long, made of one inch
aluminum pipe, and fitted at the ends with quick disconnect
couplings. The extension rods are added on, one by one, as
the auger is lowered into the hole, and removed again as
the apparatus is raised.
By starting with a brand new auger, it seemed that any
contamination of the samples from that source could be ruled
out. This was not the case however, for when the apparatus
was uncrated at Kluane Lake, quantities of an oily material
were found on both the auger and extension rods. This was
probably cutting oil which had not been removed after the
machine operations. It was impossible to effect a thorough
cleaning with the facilities at Kluane Lake, but most of the
material was removed by swabbing the auger with paper towels
soaked in Coleman fuel. This is a highly refined non-leaded
gasoline designed for use in camp stoves. Even after this
treatment, it was obvious that traces of the oily material
remained.
Procurement of the right sample containers was an
important aspect of the preparations. Two gallon wide-mouth
Nalgene jugs were chosen for use on the glacier. The mouth
was large enough so that the 3" snow core could be slid into
the jug directly from the auger without intermediate
handling. So long as the core remained frozen, it was safe
to store it in plastic. However a test had shown that,
given time, water would leach material (presumably plastici-
zer) from the jugs. Therefore, the frozen cores were flown
to base camp where they were allowed to melt at room temper-
ature: they were then transferred to glass bottler as soon
as possible. These bottles have been used as water sample
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containers by the WQO Analytical Control Laboratory for some
time, and are satisfactory for shipping samples. A special
effort was made in the precleaning of both jugs and bottles
because of the low levels of pesticide expected. The
cleaning process involved washing with soap and water.
rinsing with tap water followed by distilled water, and
finally with "distilled in glass" quality acetone. These
preparations were performed by personnel of the WQO Analyti-
cal Control Laboratory in Cincinnati, Ohio. Sixteen two-
gallon jugs and 60 one-quart bottles were sent to Kluane.
They were not opened until used.
A number of other items not directly involved in the
sampling had to be provided. A SIPHE snow kit for determin-
ing core densities was borrowed from U.S. Army CRREL. De-
contamination was not a problem here, since the short core
sections used for density measurement were discarded after-
wards. The other items needed at the sampling site were:
a tent for storage of equipment, a shovel for digging the
initial pit, notebook and pencils, labels for the Nalgene
jugs, and rubber bands and plastic bags. The plastic bags
were used to cover the hands of the man handling the auger
and the rubber bands held them on. '
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SECTION V
SAMPLING
Samples could not be taken at the high altitude camp,
because of the probability of contamination from generator
and aircraft exhaust. Therefore, a site was selected 1,000
feet WSW (the direction of the prevailing winds) of the
camp, and at a slightly higher elevation. As an additional
precaution to reduce contamination, all trash at the camp
was buried rather than burned. A four-man tent was set up
at the sampling site to store the auger and other equipment.
Next to it, a pit, one meter in depth by two meters in dia-
meter, was dug to remove the loose overburden of recently
fallen snow. The drilling took place on the floor of this
pit, and the reported drilling depths are in meters below
this surface. This pit also gave the drilling party some
protection from the wind while working.
Precaution was taken to avoid contamination during
sample collection, although the conditions on the mountain
precluded the use of really sophisticated techniques. Before
collecting any samples, three short holes were drilled and
the cores discarded in the hope of removing any last traces
of foreigh material from the auger. The drilling team was
made up of three persons. Two men operated the drill and
attached the extension rods, while the third worked with the
auger itself. This man wore large polyethylene bags over
his mittens attached by rubber bands. He alone handled the
auger or touched the core. Often surgical gloves are used
for such work, but their lack of warmth would have certainly
resulted in frostbite. Most of the drilling was done at
temperatures between 0° and -10°, and often in the wind.
The altitude of the drilling site presented a serious
problem. At 17,500 ft. the barometric pressure is half that
of sea level, and the effects of hypoxia are quite marked.
Although the drilling team was well acclimatized to altitude,
they were quickly exhausted by the heavy work. Furthermore,
the lack of oxygen seems to intensify the effect of cold.
The psychological effects are equally important* One's
work is constantly hampered by a feeling of lassitude and an
impairment of Judgement.
In a typical drilling operation the auger is lowered
into the hole and the extension rods are attached as it
descends. The actual drilling takes only a few minutes and
11
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is not difficult. Lifting the auger from the hole is very
hard work, and quite tiring. If one should let the auger
slip when it is near the surface, and most extension rods
have been removed, it would fall to the bottom of the hole.
If the depth were ten meters or greater, it would be impos-
sible to retrieve the auger, and the project would have to
be terminated unless a spare auger were available.
When the auger is lifted from the hole, the person
with hands bagged in polyethylene grasps it: while the last
extension rod is removed. Then he tips it upside down to
allow any loose snow to fall out. The core is removed by
tapping the auger with a piece of wood (bagged in polyethyl-
ene) while it is pointed into the mouth of a Nalgene sample
jug. If the core is too long to fit into the jug, it can
be broken off between the jug and,auger with one man holding
each. Once a team becomes familiar with the procedure,
cores can be transferred routinely from auger to sample jug
without touching any other surface. With each drilling
about 1/3 meter of core was obtained, the rest being loose
snow which was discarded.
Each sample jug held slightly less than one meter of
core. The temperature on the high plateau never rises to
freezing, so the samples remained frozen until they were
flown off the mountain. Thus the danger of contamination by
leaching of the plastic is minimized. At Kluane Lake the
samples were allowed to melt at room temperature without
local heating. The process took about 24 hours. As soon as
it was thawed, the sample was poured into a one quart glass
wide mouth bottle, and the bottle sealed. Only about one
half the contents of a Nalgene jug was required to fill a
one quart bottle, and the rest of the sample was discarded.
In the most favorable cases the samples touched no surfaces
other than the auger, the Nalgene jug, and the glass bottle.
Other samples had to be touched with polyethylene bagged
hands in the process of transferring it from the auger to
the jug.
There are several possible sources of contamination
in the sampling procedure. Despite the attempt to clean
the auger, it is clear that quantities of the oily material
remained on it. During the course of the drilling, bits of
the Teflon coating began to flake off the auger. This ma-
terial may be present in some samples, although it should
have been discarded with the loose snow and not included
with the core. In order to operate the drilling apparatus
properly, it is necessary to cover the drilling platform
with a board that has a hole large enough for the auger to
pass through. Even though the board was covered with mask-
ing tape and polyethylene sheeting, splinters fell into the
12
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drill hole. They should have been discarded with the loose
snow, but it is possible that some found their way into the
sample.
Several of the early cores showed a dark band on the
outside about i inch from the cutting head of the auger.
This discoloration was present only on the surface of the
sample. In all cases but one, it was broken off and dis-
carded. As a control, it was retained on sample #5- It
could have been present to a lesser extent in other samples,
and gone by unnoticed. In any event it had no effect on
sample #5, as shown by analysis.
After the samples were thawed and placed in glass
bottles, some solid material was observed in them. If a
sample was shaken and held toward the light, one could see
a few very small pieces of fuzz which resembled bits of
wool. Neither the source nor the nature of this material
has been ascertained. The drilling team wore outer clothes
of nylon or nylon-cotton mix. Although they did occasional-
ly wear wool gloves, they took great care not to touch the
samples, either directly or indirectly, except with hands
encased in plastic bags.
At the end of the drilling, one sample was deliberate-
ly mishandled as a control. The drilling team rubbed it
with gloved hands and against their pants. If there is any
contamination arising from clothing, this control should
show at least 100 times as much as the other samples.
13
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SECTION VI
ANALYSIS
As soon as possible after the termination of the Mt.
Logan project, the samples contained in glass bottles were
sent to the Analytical Control Laboratory, WQO, Cincinnati,
Ohio for analysis. This was performed using vapor phase
chromatographic techniques developed at that laboratory.
DDT was not detected in any of the samples. The lower
limit of detectability for DDT was approximately 5 ng/1 for
eight of the samples. Due to interference, apparently from
polychlorinated biphenyls (PCB's), 10 to 50 ng/1 of DDT
could have been present in the remaining twelve samples and
not been detected. Efforts to remove the PCB's from the
extract to allow for more sensitive determination of DDT
were only partially successful. Thus the results are in
part inconclusive. It seems highly likely however, that the
DDT concentration in all samples was less than 5 ng/1 on the
basis of the eight samples which did not show PCB interference,
The source of the apparent PCB's (Aroclors 1260 or
1262) is not known for certain, although a residue of the
oily substance on the auger is a likely suspect. There is
no pattern of occurrence of the PCB's in the samples. Three
scattered samples contained significant quantities of what
appears to be Aroclor 1260 or 1262. Samples 1 through 3 and
5 through 10 contained varying amounts of a similar, but not
identical material. The Kluane Lake sample and the five
samples received in the second shipment (#15,16,17,18,20)
did not contain such material. All possible sources of
PCB1s in the laboratory were thoroughly checked, and there
is no reason to suspect that this material was introduced
during the analyses.
The dark band retained in core sample 5 had no appar-
ent effect on the analytical results. Sample 20, deliber-
ately handled so as to contaminate it, gave a peak for
p,p'-DDT on one gas chromatographic column. However, this
was not confirmed by analysis on a second column.
All samples produced a broad initial peak with 3 to 4-
distinct early eluting- peaks which were more or less typi-
cal of the distilled water check that was made on the plastic
jugs. In addition, samples 1 through l*f gave a high general
background response to the electron capture detector.
15
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As a matter of curiosity, the pH (which may not
correspond to the original pH) of randomly selected samples
from the first shipment (sample 1 through 14 plus Kluane
Lake) was measured on arrival in the laboratory as was
that of the five samples that arrived in the second shipment.
Sample 20, deliberately "contaminated" was low with pH 6.1.
The Kluane Lake sample was high with pH 8.0 All others
ranged from 6.3 to 6.9.
In an attempt to fix the source of the FOB contamina-
tion, the auger and one of the extension rods were sent to
the laboratory where they were sampled by rinsing with
hexane. The extension rod clearly contained traces of an
oily material inside the stainless steel fitting at the end.
This appeared to be a cutting oil. The chromatogram showed
a series of early eluting peaks, but no traces of Aroclors.
These early peaks would not have obscured the presence of
DDT. None of the material from the rods was found in the
snow samples. The rinsings from the auger gave a chromato-
gram which was rich in peaks, as well as a high general
background response. A similar high background was observed
in snow samples l-l4. This fraction also contained a quan-
tity of halogenated material, which was an Aroclor, a mix-
ture of Aroclors, or a similar substance. Its chromatogram
resembled, but did not exactly reproduce that of Aroclors
1260 and 1262. Even though an exact match cannot be made,
it is reasonable to conclude that the auger was responsible
for the contamination of the snow sample. The material is
a complex mixture, and it is possible that some components
were preferentially lost from the auger as drilling proceed-
ed. This contention is supported by the fact that the last
five snow samples showed no PCB contamination.
One sample was obtained for trace metal analysis. It
was taken as a snow core extending from a depth of l£ to 2&
meters. It was stored in a Nalgene jug and acidified with
distilled nitric acid as soon as it melted. It remained in
the plastic container until use. Simultaneous analysis for
19 elements was performed on a direct reading emission spec-
trometer. Pour elements were detected: boron at 4 ng/ml,
cadmium at 9 ng/ml, chromium at 2 ng/ml, and iron at 4? ng/ml,
The high levels of cadmium and especially iron suggest con-
tamination from the alloy steels of\ the auger. This is not
surprising; other workers have notedx that it is extremely
difficult to avoid metal ion contamination when steel sam-
pling tools are used (1).
16
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Method of Analysis (2)
Each sample was transferred to a two liter separatory
funnel. The sample bottle was rinsed with 60 ml. of hexane
which was then used to extract the sample. This operation
was repeated a second and a third time. The combined ex-
tracts were dried by passing through a column of anhydrous
sodium sulfate and collected in a Kuderna-Danish (K-D)
flask. They were concentrated in the K-D to- about 6 ml. on
a steam bath and finally to a minimum of 2 ml. on a warm
water bath. Up to 10 microliters was injected for gas
chromatographic analysis on two different columns.
Gas chromat©graphic conditions were as.follows:
1. A Microtek Model 179 equipped with a Ni0-^ detector, an
aluminum column 6' x i" O.D. packed with Gas-Chrom Q (60/80
mesh) coated with 5% OV-17, and a nitrogen carrier flow of
100 ral./min. Temperatures were: injection port, 250° C.;
column oven, 205° C.; and detector, 360° C.
2. A Perkin-Elmer Model 900 equipped with a tritium
parallel plate electron capture detector, an aluminum
column 81 x 1/8" O.D. packed with Gas-Chrom Q (60/80 mesh)
coated with $% QP-1 plus 3# Dow-200, and a nitrogen carrier
flow of 40 ml./min. Temperatures were: injection port,
250° C.; column oven, 185° C,; and detector, 205° C.
17
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TABLE I
COLLECTION DATA AND ANALYTICAL RESULTS FOR SNOW SAMPLES
Sample No.
(Lab. No.)
I (508)
2 (509)
3 (510)
4 (511)
5 (512)
6 (513)
7 (514)
8 (515)
9 (516)
10 (517)
11 (518)
12 (519)
13 (520)
14 (521)
15 (539)
16 (5^1)
17 (540)
18 (542)
20 (543)
KLAb (506)
KLAa (507)
7-13
7-13
7-13
7-13
7-13
7-13
7-16
7-16
7-16
7-16
7-20
7-20
7-20
7-20
7-20
7-20
7-21
7-21
8-5
7-20
7-20
Depth
(meters)
DDT
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
PCS £H
P
P
P
+
P
P
P
P
P
P
ND
ND
+
ND
ND
ND
ND
ND
ND
6.5
-
-
6.4
6.3
-
6.4
-
6.4
6.9
6.5
6.6
6.4
6.1
8.0
Density
(gm/oc)
0.39
0.55
0.54
not analyzed
Notes;
Depths are approximate and refer to the average depth of
the core.
ND - Not detected.
( + ) - Aroclor 1260 or 1262
P - Similar but not identical to Aroclor 1260 or 1262.
pH values determined after arrival at Cincinnati; they may
not reflect the original pH values.
Sample 20 was deliberately contaminated by handling.
Samples KLAa and KLAb were taken from the waters of Kluane
Lake as a control.
18
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TABLE II
RESULTS OP TRACE METAL ANALYSIS
Metal
Zinc
Cadmium
Arsenic
Boron
Phosphorous
Iron
Molybdenum
Manganese
Aluminum
Beryllium
Copper
Silver
Nickel
Cobalt
Lead
Chromium
Vanadium
Barium
Strontium
ND
9 ppb
ND
b ppb
ND
ty ppb
ND
ND
ND
ND
ND
ND
ND
ND
ND
2 ppb
ND
ND
ND
less than 2 ppb
less than 28 ppb
less than 10 ppb
less
less
less
less.
less
less
less
less
less
than
than
than
than
than
than
than
than
than
4 ppb
1 ppb
4 ppb
0.02 ppb
1 ppb
0.2 ppb
2 ppb
2 ppb
^ ppb
less than ^ ppb
less than 1 ppb
less than 1 ppb
Notes:
—1--1 ^
Results are for total metals (dissolved + suspended).
Results are given as nanograms per milliliter.
19
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SECTION VII
ACKNOWLEDGMENTS
The Arctic Institute of North America provided logistic
support for the Mt. Logan Project. Special recognition is
given to the Institute's glacier pilot, Mr. Philip P. Upton,
whose flying skill was indispensable to the existence of
the high camp.
Thanks go to the support team of the Logan high camp
who volunteered their help with the arduous work of snow
coring.
This project was supported by the Water Quality Office
of the Environmental Protection Agency. James W. Eichelberger
of the Analytical Control Laboratory, Cincinnati, Ohio,
gave invaluable assistance with the DDT analyses. The metal
analyses were performed by John P. Kopp.
The help of Carol Harden in preparation of the manu-
script is gratefully acknowledged.
21
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SECTION VIII
REFERENCES
1. Murozumi, M., Chow, T.J., and Patterson, C., "Chemical
Concentrations of Pollutant Lead Aerosols, Terrestrial
Dusts and Sea Salts in Greenland and Antarctic Snow
Strata," Geochimica et Cosmochimica Acta. 33. pp 124-7-
"PWPCA Method for Chlorinated Hydrocarbon Pesticides
in Water and Wastewater," U.S. Department of the
Interior, Federal Water Pollution Control Administra-
tion, Division of Water Quality Research, Analytical
Control Laboratory, Cincinnati, Ohio, April, 1969.
23
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SELECTED WATER
RESOURCES ABSTRACTS
INPUT TRANSACTION FORM
1. Report No,
4. Title
"Sampling of Glacial Snow for Pesticide Analysis"
7. Author(s) Thomas R. Stengle (1)
James J. Lichtenberg (2)
f "
i 3. Accession No.
;w
"jr.-^jjdrtJJatff / "/v-v";'"
I-'*?"'** '."Vv>. £/ "< WASHINGTON, D. C. 20240
institution AQC Laboratory, EPA, Cincinnati, Ohio
WRSIC 102 (REV. JUNE 1B7l)
SPO 913.261
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