United States
Environmental Protection
Agency
Environmental Monitoring
Systems Laboratory
Las Vegas NV 89193-3478
Research and Development
EPA/600/S4-87/03O Jan. 1988
&ER& Project Summary
Direct/Delayed Response
Project: Field Operations and
Quality Assurance Report for
Soil Sampling and Preparation
in the Northeastern United
States
D. S. Coffey, M. L. Papp, J. K. Bartz, R. D. Van Remortel, J. J. Lee,
D. A. Lammers, M. G. Johnson, and G. R. Holdren
The Direct/Delayed Response Pro-
ject Soil Survey includes the mapping,
characterization, sampling, prepara-
tion, and analysis of soils in order to
assess watershed response to acidic
deposition within various regions of the
United States. Soil samples collected
by sampling crews in the Northeastern
region were processed at preparation
laboratories before being sent for
analysis at analytical laboratories.
Volumes I and II summarize the pro-
cedural and operational compliance
with protocols used by the sampling
crews and by the preparation labora-
tories, respectively. Deviations from
protocols and difficulties encountered
are identified and discussed. Recom-
mendations are made for program
improvement.
In general, soil sampling activities
during the survey proceeded as
planned. A review of the soil data
suggests that the integrity of the soil
samples was maintained during the
preparation activities. In most cases,
sampling crews and laboratory person-
nel adhered to protocols.
This report was submitted in partial
fulfillment of contract number 68-03-
3249 by Lockheed Engineering and
Management Services Company, Inc.
under the sponsorship of the U.S.
Environmental Protection Agency. The
report covers a period from March
1986 to December 1986, and work
was completed as of September 1987.
This Project Summary was devel-
oped by EPA's Environmental Monitor-
ing Systems Laboratory. Las Vegas.
NV, to announce key findings of the
research project that is fully docu-
mented in two separate volumes of the
same title (see Project Report ordering
information at back).
Introduction
The U.S. Environmental Protection
Agency (EPA), in conjunction with the
National Acid Precipitation Assessment
Program (NAPAP), has designed and
implemented a research program to
predict the long-term response of
watersheds and surface waters in the
United States to acidic deposition. Based
on this research, each watershed system
studied will be classified according to the
time scale in which it will reach an acidic
steady state, assuming current levels of
acidic deposition. The Direct/Delayed
Response Project (DDRP) was designed
as the soil study complement to the
aquatic resources program.
After a pilot soil survey was accomp-
lished, a sampling design for the soil
survey of the Northeastern region was
developed. Representative watersheds
were selected for soil and vegetation-
mapping, and specific sampling sites
later were characterized and sampled.
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Through an interagency agreement, soil
scientists from the Soil Conservation
Service were assigned the task of
mapping and sampling soils in the region.
Four preparation laboratories were
contracted through interagency agree-
ments to receive and process the soil
samples and to perform laboratory
analyses for certain parameters. Labor-
atories located atthe University of Maine,
the University of Connecticut, the Uni-
versity of Massachusetts, and Cornell
University in New York were selected for
these tasks because of the proximity of
each laboratory to the sampling sites and
analytical experience with soils of the
region. The laboratory managers were
responsible for ensuring that the integ-
rity of the soil samples was maintained
after the samples were delivered by the
sampling crews to the preparation
laboratories.
AH soil survey participants were
required to comply with specified soil
sampling and preparation protocols,
which are included as Appendix A in both
volumes
Soil samples processed at the prepa-
ration laboratories were obtained from
routine sampling sites located in Maine,
Vermont, New Hampshire, Massachu-
setts, Rhode Island, Connecticut, New
York, and Pennsylvania. Additional
samples were obtained from special
interest watersheds in new York and
Massachusetts. Upon receipt of bulk soil
samples from the sampling crews,
laboratory personnel performed the
following analyses on the samples: (1)
air-dry moisture determination, (2) deter-
mination of the 2- to 20-mm rock
fragment percentage by weight, (3)
qualitative test for inorganic carbon, and
(4) clod analysis for determination of bulk
density.
Laboratory personnel prepared analyt-
ical samples derived from homogenized,
air-dry bulk samples. The analytical
samples were labeled and were organ-
ized according to their parent pedons.
Analytical batches were assembled, each
containing no more than 42 samples. The
samples were randomized within each
batch by the laboratory manager. The
assembled batches were shipped to
various analytical laboratories con-
tracted by EPA for further analyses.
Three types of quality assurance (QA)
samples were included in each batch of
samples submitted to the analytical
laboratory: (1) field duplicates, (2) prep-
aration duplicates, and (3) natural audit
samples. Portions of the data from the
field duplicates are evaluated in Volumes
I and II, and additional data for all QA
samples will be evaluated in the forth-
coming QA report for the analytical
laboratory data.
One soil horizon per sampling crew per
day was sampled in duplicate as specified
in the protocols. The first sample of the
pair is considered the routine sample,
and the second sample is referred to as
the field duplicate. The field duplicate
underwent the same preparation steps
as its associated routine sample. This
procedure allows an estimate to be made
of sampling error and horizon variability.
One sample per batch was chosen by
the laboratory manager to be processed
and then split into two subsamples. One
of the pair retained the routine sample
code and the other was assigned the
preparation duplicate designation. Ana-
lytical data from the preparation dupli-
cates allows the range of physical and
chemical characteristics for splits of the
sample material to be determined and
allows an estimate to be made of the
error attributed to subsampling.
Each batch contained two natural audit
samples supplied by EPA, but the sam-
ples did not undergo processing at the
preparation laboratory. These samples
were used to assess the performance of
the analytical laboratories.
Field data received from the sampling
crews and raw data from the preparation
laboratory analyses were doucmented in
log books and were submitted to EPA for
use during data verification.
QA and quality control (QC) measures
were applied in order to maintain con-
sistency in soil sampling and preparation
protocols and to ensure that the soil
sample analyses would yield results of
known quality. Field and laboratory
personnel received training in the sam-
pling and preparation procedures and
analytical methods. QA representatives
conducted on-site systems audits of the
sampling crews and the preparation
laboratories. Weekly communication
between the QA staff and the sampling
and preparation personnel was estab-
lished to identify, discuss, and resolve
issues.
Volume I of the report presents the
results of the sampling operations and
QA program, and Volume II of the report
presents the results of the preparation
laboratory operations and QA program.
Recommendations for program improve-'
ment are made in both documents.
Procedures
The QA/QC design for the soil sam-
pling and preparation included training
personnel in the protocols to be followed,
establishing a communications network,
assessing data quality, and accomplish-
ing on-site systems audits. The data are
evaluated statistically using analytical
data from the replicate clods and from
the duplicate samples that were included
in each batch of routine samples.
Field and laboratory personnel
attended a regional pre-sampling work-
shop in Orono, Maine during August
1985. The purpose of the workshop was
to review the sampling and preparation
protocols and discuss key activities.
A computer algorithm was used to
make random selections of sampling
locations within representative
watersheds containing the desired sam-
pling and vegetation classes. Sampling
crews were tasked with collecting 5.5-
kilogram bulk samples from selected
sampling sites that met the specific
sampling class and vegetation class
requirements. A soil horizon normally
was subdivided for sampling if its thick-
ness was greater than 20 cm. A coded
field data form was used by all sampling
crews to facilitate data entry into com-
puter files by QA personnel. The sam-
pling effort resulted in a total of 306
routine pedons sampled.
The sampling crews were responsible
for the full characterization of their
assigned pedons to a depth of 150 cm,
or to bedrock if shallower. Samples were
taken from representative parts of del-
ineated horizons, were sieved to exclude
rock fragments exceeding 20 mm in
diameter, and were sealed in plastic
bags. All samples were kept in styrofoam
coolers until they could be delivered to
cold storage facilities at the preparation
laboratories. Soil clods used to estimate
bulk density also were collected.
After retrieval from cold storage, bulk
samples were spread out on trays to air
dry until constant weight was achieved.
After recording the weight of the air-dry
bulk sample, the soil peds were crushed
to allow passage of the less than 2-mm
soil fraction through a No 10 mesh sieve.
The rock fragments retained on the sieve
constituted the 2- to 20-mm pebble
fraction. The fragments were weighed
and packaged for storage.
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A Jones-type, 3/a-inch riffle splitter was
used to homogenize the less than 2-mm
fraction of the samples. The soil was
placed through the riffle splitter at least
seven times in succession. One-half of
each sample was placed into a plastic
sample bag for archiving, and the other
half was passed through the riffle spiltter
until an approximately one-kilogram
subsample was obtained. The subsample
was labeled and placed into a batch of
samples for delivery to an analytical
laboratory.
One gram of soil was placed in the well
of a procelam spot plate, was saturated
with deionized water, and was stirred to
release any entrapped air. The sample
was observed through a stereoscope in
order to detect any chemical reaction
when three drops of 4NHCI were added.
The soil clods collected by the sampling
crews were weighed at the laboratory
and were dipped in a 1.4 or 1:7
saran:acetone mixture The dipping
procedure was repeated until each clod
was impervious to water. The clods were
suspended from a line, were allowed to
dry briefly, and were reweighed.
Approximately 800 ml deionized water
in a one-liter beaker was de-gassed by
boiling, was allowed to cool to room
temperature, and was tared on a balance.
Each clod was submerged in the water
to determine the weight displacement on
the balance. The clods were placed in
a drying oven for 48 hours and, after
cooling, were weighed. A two-hour heat
treatment in a 400°C muffle furnace
allowed the saran to vaporize, and the
clods were cooled and reweighed. Each
clod was crushed and was passed
through a No. 10, 2-mm mesh sieve to
determine percent by weight of rock
fragments, which was used to adjust the
bulk density for rock fragment content.
Results and Discussion
The sampling crews encountered a
number of logistical and procedural
difficulties that are detailed in Volume
I Sampling was begun under unusually
dry conditions, however, mid-way
through the sampling, Hurricane Gloria
brought excessive rainfall in a short
period that impeded access to some
locations for several weeks Helicopters
were used to obtain access to three
watersheds in New York Access was
denied by landowners to four watersheds
in the region. Inappropriate site condi-
tions also were encountered occasion-
ally. The vegetation class did not always
correspond to the class expected at a
sampling location. Site selection protoc-
ols were followed by all but one of the
sampling crews.-
Difficulties were encountered when
sampling wet or saturated mineral soils
and organic soils. Soils with a dense
substratum or numerous large rock
fragments posed some additional sam-
pling constraints. Efforts were made to
avoid contamination of the samples from
sampling equipment, adjacent soil horiz-
ons, and agricultural chemicals such as
fertilizers or herbicides. Occasional
discrepancies were noted in regardtothe
sieving of rock fragments, sample label-
ing, collection of clods, and entry of data
on the field data forms.
Each preparation laboratory provided
the sampling crews with convenient
access to cold storage. A sample receipt
log book was kept at each facility to allow
sampling crews to log in the samples.
Each laboratory was responsible for
checking that all samples delivered by the
sampling crews were recorded accu-
rately in the log book. The temperature
of the storage facilities was maintained
at the contact-specified 4°C.
The laboratory managers were respon-
sible for tracking the distribution of
equipment to the sampling crews. The
sampling crews usually picked up supp-
lies at the time samples were being
delivered to the cold storage facility. The
sampling crews were responsible for
listing in the equipment log book all
supplies taken. Equipment shortages
were reported to EMSL-LV during the
weekly conference call. Laboratory
personnel were tasked with mixing the
saran dipping solution used for coating
clods in the field. After the soil prepa-
ration activities were completed, leftover
supplies were inventoried, were packed
in boxes, and were returned to EMSL-
LV for storage.
Although there were no deviations
from the specified protocols for sample
drying, concerns were raised about the
collection of water on the trays and the
encrustation of certain organic samples.
Both situations encouraged microbial
growth that may have altered the com-
position of the affected samples.
There were no deviations from the
specified protocols for the air-dry mois-
ture determination, the crushing and
sieving operation, the rock fragment
determination, the soil homogenization,
the test for incorganic carbon, or the bulk
density determination.
The preparation laboratories were
provided with packaging materials and
a Federal Express charge number for
overnight shipment of samples to the
designated analytical laboratories. The
individual samples were labeled, were
placed in canvas bags, and were packed
in cardboard boxes for shipment.
The sampling crews and the prepara-
tion laboratories were provided with log
books to use for recording data. Each
laboratory manager was instructed to
organize log books containing the follow-
ing labels, information, and analytical
data: bulk sample labels, clod labels,
sample receipt, equipment, percent
moisture, percent rock fragments, bulk
density, inorganic carbon, and sample
processing. Because a standard format
for each log book was not specified, there
was variation among the laboratories. As
a result, verification of the data took more
time than was expected.
Weekly conference calls assisted in
keeping the sampling crews and prep-
aration laboratories operating efficiently
and consistently by providing a forum
that allowed potential difficulties to be
discussed and resolved. Issues discussed
during the conference calls included site
access difficulties, supply shortages,
record keeping, and clarification of
protocols.
The quality of the sampling effort and
the preparation activities are assessed
according to the following data quality
characteristics: (1) precision, (2) accu-
racy, (3) representativeness, (4) com-
pleteness, and (5) comparability. Both
Volume I and Volume It provide details
on the evaluation of data quality for
various survey activities. As an example,
a completely randomized design model
was selected for the statistical estimation
of precision, using a pooled standard
deviation and coefficient of variation to
quantify the imprecision.
Conclusions and
Recommendations
A series of useful recommendations
are made in both volumes, based on
information supplied by the sampling
crews, preparation laboratory personnel,
QA staff, and other survey participants.
The recommendations are presented for
possible implementation in future sur-
veys, and can be summarized as follows:
• Prior site selection by sampling
leaders
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• Methods for artificially draining sat-
urated soil pits
• Procurement of specialized sampling
equipment
• Uniformity of staff evaluations and QA
systems audits
• Standardized forms and log books for
record keeping
• Computerized data entry procedures
• Sample drying techniques
• Assessment of air-dry moisture
content
• QA/QC measures for bulk density
determination
• Documentation of conference calls
• Development of data quality
objectives
The Northeastern soil survey was
successful in terms of collecting data of
known and documented quality that will
be utilized by many end users. The
coordination of sampling and preparation
activities among the many participants
was a large-scale, complex task that was
performed as originally conceived with
a minimum of unanticipated difficulties
and modifications.
D. S. Coffey is with Tetra Tech, Inc.. Bellevue, WA 98005; M. L Papp, J. K.
Bam. andR. D. Van Remortel are with LockeedEngineering and Management
Services Co., Inc., Las Vegas, NV 89119; the EPA authors J. J. Lee and
D. A. Lammers are with the Environmental Research Laboratory, Corvallis.
OR 97333; M. G. Johnson and G. R. Holdren are with Northrop Services,
Inc.. Corvallis. OR 97333.
L. J. Blume is the EPA Project Officer (see below).
The complete report consists of two volumes, entitled "Direct/Delayed Response
Project: Field Operations and Quality Assurance Report for Soil Sampling
and Preparation in the Northeastern United States:"
"Volume I. Sampling." (Order No. PB 88-120 597/AS; Cost: $25.95)
"Volume II. Preparation,"(Order No. PB 88-120 605/AS; Cost: $19.95)
The above reports will be available only from: (cost subject to change)
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
P.O. Box93478
Las Vegas, NV 89193-3478
United States
Environmental Protection
Agency
Center for Environmental Research
Information
Cincinnati OH 45268
MAR-2'83
•£**
Official Business
Penalty for Private Use S300
EPA/600/S4-87/030
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