United States
Environmental Protection
Agency
Environmental Monitoring
Systems Laboratory
Las Vegas NV 891 93-3478
Research and Development
EPA/600/S4-87/041 Feb. 1 988
Project Summary
Direct/Delayed Response
Project: Field Operations and
Quality Assurance Report for
Soil Sampling and
Preparation in the Southern
Blue Ridge Province of the
United States
D. S. Coffey, J. J. Lee, J. K. Bartz, R. D. Van Remortel, M. L. Papp,
G. R. Holdren, and M. F. Haren
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 Southern Blue
Ridge Province were processed at two
preparation laboratories before being
sent for analysis at four analytical
laboratories. Volumes I and II summar-
ize the procedural and operational
compliance with protocols used by the
sampling crews and by the preparation
laboratories, respectively. Deviations
from protocols and difficulties encoun-
tered are identified and discussed.
Recommendations are made for pro-
gram 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.,
and of contract number 68-03-3246 by
Northrop Services, 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 com-
pleted as of October 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
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as the terrestrial complement to the
Aquatic Effects Research Program.
After a pilot soil survey was accom-
plished, a sampling design for the soil
survey of the Southern Blue Ridge
Province was developed. Representative
watersheds were selected for soil and
vegetation mapping, and specific sam-
pling sites later were characterized and
sampled. Through an interagency agree-
ment, soil scientists from the U.S.
Department of Agriculture Soil Conser-
vation Service were assigned the task of
mapping and sampling soils in the region.
The services of two preparation labor-
atories were obtained through inter-
agency agreements to receive and pro-
cess incoming soil samples and to
perform laboratory analyses for certain
parameters. Laboratories located at the
University of Tennessee in Knoxville and
Clemson University in Clemson, South
Carolina were selected for these tasks
because of the proximity of each labor-
atory to the sampling sites and analytical
experience with soils of the region. The
laboratory managers were responsible
for supervising the preparation of the soil
samples and for ensuring that the
integrity of the samples was maintained
at the laboratories.
All soil survey participants were
required to comply with specified soil
sampling and preparation protocols,
which are included as appendices in both
Volume I and Volume II.
Soil samples processed at the prepa-
ration laboratories were obtained from
routine sampling sites located in Geor-
gia, Tennessee, South Carolina, and
North Carolina. Additional samples were
obtained from special interest water-
sheds in North Carolina and Virginia.
Upon receipt of bulk soil samples from
the sampling crews, laboratory person-
nel performed the following analyses on
the samples: (1) air-dry moisture deter-
mination, (2) determination of the 2- to
5-millimeter and 5- to 20-millimeter rock
fragment percentages 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 spatial horizon variability and sampling
bias.
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
sample pairs supplied by EPA, but the
samples did not undergo processing at
the preparation laboratory. They were
submitted as blind samples in order to
assess the performance of the analytical
laboratories.
Field data received from the sampling
crews and raw data from the preparation
laboratory analyses were documented 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 soil sampling operation
and QA program, and Volume II of th
report presents the results of the prep
aration laboratory operations and Q/
program. Recommendations for prograr
improvement are made in bot
documents.
Procedures
The QA/QC design for the soil sam
pling and preparation included trainin
personnel in the protocols to be follower
establishing a communications networl<
assessing data quality, and accomplish
ing on-site systems audits. The data ar
evaluated statistically using analytics
data from the replicate clods and fron
the duplicate samples that were include'
in each batch of routine samples.
Field and laboratory personne
attended a regional pre-sampling work
shop in Knoxville, Tennessee durini
March 1986. The purpose of the work
shop was to review the sampling am
preparation protocols and discuss ke'
activities.
A computer algorithm was used t<
make random selections of samplim
locations within representativi
watersheds containing the desired sam
pling and vegetation classes. Samplim
crews were tasked with collecting
approximately 5.5-kilogram bulk sample;
from selected sampling sites that met th<
specific sampling class and vegetatior
class requirements. A soil horizon nor
mally was subdivided for sampling if its
thickness was greater than 20 centime
ters. A coded field data form was usec
by all sampling crews to facilitate date
entry into computer files by QA person-
nel. The sampling effort resulted in a tola
of 110 routine pedons sampled.
The sampling crews were responsible
for the full characterization^f theii
assigned pedons to a depth c/7 ^OC
centimeters, or to bedrock if shallower
Samples were taken from representative
parts of delineated horizons, were sievec
to exclude rock fragments exceeding 2C
millimeters in diameter, and were sealec
in plastic bags. All samples were tem-
porarily refrigerated in styrofoam coolers
until they could be delivered to cole
storage facilities at the preparation
laboratories. Replicate soil clods used tc
estimate bulk density also were
collected.
After retrieval from cold storage, bull
samples were spread out on paper to aii
dry until constant weight was achieved
After recording the weight of the air-dn
bulk sample, the soil peds were crushec
to allow passage of the less than 2-
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millimeter soil fraction through No. 4 and
No. 10 sieves. The rock fragments
retained on the No. 4 sieve constituted
the 5- to 20-millimeter coarse pebble
fraction, and the fragments retained on
the No. 10 sieve constituted the 2- to
5-millimeter fine pebble fraction. The
fragments were weighed and then
packaged for storage.
A Jones-type, %-inch riffle splitter was
used to homogenize the less than 2-mm
fraction of the soil samples. Each sample
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
splitter until a 500-gram subsample was
obtained. The subsample was labeled
and placed into a batch of samples for
delivery to an analytical laboratory.
One gram of air-dry soil was placed
in the well of a porcelain spot plate, was
saturated with deionized water, and was
stirred to release any entrapped air. The
sample was observed through a micro-
scope or stereoscope in order to detect
any chemical reaction when three drops
of 4N HCI were added.
The soil clods collected by the sampling
crews were weighed at the laboratory
and were dipped in a 1:7 sararracetone
mixture. The dipping procedure was
repeated until each clod was assumed
to be impervious to water. The clods were
dried briefly and were reweighed.
Approximately 800 milliliters of deion-
ized 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-
riuui 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 2-millimeter sieve
to determine percent by weight of rock
fragments, which was used to adjust the
bulk density calculation for rock fragment
content.
Results and Discussion
The sampling crews encountered a
number of logistical and procedural
difficulties that are detailed in Volume
I. The presence of thick vegetation made
it difficult to locate and gain access to
the sampling sites. Helicopters were
used to access two watersheds in Great
Smoky Mountains National Park. Vege-
tation class or sampling class modifica-
tions were made at six sites, and two
sites were removed from the sampling
list because the appropriate sampling
class could not be located in the
watershed. The vegetation class did not
always correspond to the class expected
at a sampling location. Site selection and
sampling protocols generally were fol-
lowed by all of the sampling crews.
Hand pumps were used to control
seepage when sampling wet or saturated
soils. Efforts were made to avoid con-
tamination of the samples from sampling
equipment, adjacent soil horizons, and
agricultural chemcials such as fertilizers
or herbicides. Occasional discrepancies
were noted in regard to sample labeling,
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 faciity 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 contract-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 sup-
plies at the time samples were being
delivered to the cold storage facility. The
sampling crews were asked to list in the
equipment log book all supplies taken.
Equipment shortages were reported to
EPA during the weekly conference call.
Laboratory personnel usually provided
the saran dipping solution used for
coating clods in the field. After the soil
preparation activities were completed,
leftover supplies were inventoried and
then sent to EPA for storage.
Although there were no deviations
from the specified protocols for sample
drying, concerns were raised about the
length of time necessary to dry the
samples. The extended drying period
allowed the samples to be exposed to
possible airborne contamination for
longer periods than was necessary.
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 inorganic carbon, or the bulk
density determination.
The preparation laboratories were
provided with packaging materials and
an express mail charge number for
overnight shipment of samples to the
designated analytical laboratories.
The sampling crews and the prepara-
tion laboratories were provided with log
books to use in 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 II 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 error due to 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:
• Improved site selection criteria
• Equipment and supply tracking and
inventory system
• Procurement of specialized sampling
equipment
• Uniformity of staff evaluations and QA
systems audits
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• Modifications to the computerized
field data form
• Standardized forms and log books for
record keeping
• Computerized data entry procedures
• Sample drying techniques
• Alternative methods for determining
field moisture
• QA/QC measures for bulk density
determination
• Alternative method for identifying
inorganic carbon
• Documentation of conference calls
• Development of data quality
objectives
The Southern Blue Ridge Province soil
survey was successful in terms of
collecting data of known and docu-
mented 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. C of fey is with Tetra Tech, Inc., Bellevue, WA 98005; the EPA author
J. J. Lee is with the Environmental Research Laboratory, Corvallis, OR 97333;
J. K. Bartz, R. D. VanRemortel, M. L. Papp, andM. F. Haren are with Lockheed
Engineering and Management Services, Inc., Las Vegas, NV 89119; and G.
R. Holdren is with Northrop Services. 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 Southern Blue Ridge Province of the United States:"
"Volume I. Sampling," (Order No. PB 88-154 257'/AS; Cost: $25.95, subject
to change)
"VolumeII. Preparation, "(OrderNo. PB88-154 265/AS; Cost: $ 14.95, subject
to change)
The above reports will be available only from: (costs subject to change)
National Technical Information Service
5285 Port Royal Road
Spring field, 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. Box 93478
Las Vegas. NV 89193-3478
United States
Environmental Protection
Agency
Center for Environmental Research
Information
Cincinnati OH 45268
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