v>EPA
United States Office of Acid Deposition, Environmental EPA/600/8-87/026
Environmental Protection Monitoring and Quality Assurance June 1987
Agency Washington DC 20460
Research and Development
Western Lake Survey
Phase I
Quality Assurance
Plan
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Pacific
Northwest (4B)
California (4A
Northern
Rockies (4C)
Central
Rockies (4D:
J
Southern
Rockies (4E)
J
Subregions of the Western Lake Survey - Phase I
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EPA 600/8-87/026
June 1987
Western Lake Survey
Phase I
Quality Assurance Plan
A Contribution to the
National Acid Precipitation Assessment Program
U.S. Environmental Protection Agency
Office of Research and Development
Washington, DC 20460
Environmental Monitoring Systems Laboratory - Las Vegas. NV 89119
Environmental Research Laboratory - Corvallls, OR 97333
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Notice
The information in this document has been funded wholly or in part by the U.S.
Environmental Protection Agency under contract numbers 68-03-3249 and
68-03-3050 to Lockheed Engineering and Management Services Company,
Inc., No. 68-03-3246 to Northrop Services, Inc., and Interagency Agreement
Number 40-1441-84 with the U.S. Department of Energy. It has been
subject to the Agency's peer and administrative review, and it has been
approved for publication as an Agency document.
Mention of trade names or commercial products does not constitute
endorsement or recommendation for use
This document is one volume of a set which fully describes the Western Lake
Survey-Phase I. The complete document set includes the major data report (2
volumes), quality assurance plan, analytical methods manual, field operations
report, and quality assurance report. Similar sets are being produced for each
Aquatic Effects Research Program component project. Colored covers,
artwork, and use of the project name in the document title serve to identify
each companion document set.
Proper citation of this document is:
Silverstein, M.E., S.K. Drouse, J.L. Engels, M.L. Faber, and T.E. Mitchell-Hall.
National Surface Water Survey, Western Lake Survey (Phase l-Synoptic
Chemistry) Quality Assurance Plan. EPA-600/8-87/C26. U.S. Environmental
Protection Agency, Las Vegas, Nevada.
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Abstract
The purpose of the National Surface Water Survey of the National Acid
Precipitation Assessment Program is to evaluate the present water chemistry of
lakes and streams, to determine the status of certain biotic resources, and to
select regionally representative surface waters for a long-term monitoring
program to study changes in aquatic resources. The Western Lake Survey is
part of the National Surface Water Survey.
The U.S. Environmental Protection Agency requires that data collection
activities be based on a program which ensures that the resulting data are of
known quality and are suitable for their intended purpose. In addition, it is
necessary that the data obtained be consistent and comparable. For these
reasons, all analysts participating in the study must use the same reliable,
detailed analytical methodology.
The quality assurance plan and the analytical methods used during Phase I of
the Western Lake Survey are based on those used during Phase I of the
Eastern Lake Survey; analytical laboratory methods are identical for the two
surveys, but some of the field laboratory methods were modified for the
Western Lake Survey. Sampling protocols are significantly different in that
ground access as well as helicopter access was used to collect samples for
the Western Lake Survey.
This quality assurance plan describes in detail the quality assurance
requirements and procedures that are unique to the Western Lake Survey -
Phase I. Quality assurance requirements and procedures that were adopted
verbatim from the Eastern Lake Survey - Phase I are referenced here and are
discussed in detail in the quality assurance plan prepared for that survey.
This report was submitted in partial fulfillment of Contract No. 68-03-3249 by
Lockheed Engineering and Management Services Company, Inc., under the
sponsorship of the U.S. Environmental Protection Agency. This report covers a
period from September 10, 1985, to November 4, 1985. Work was completed
as of May 14, 1986.
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Table of Contents
Page
Abstract iii
List of Figures vii
List of Tables viii
Abbreviations ix
Acknowledgments xi
1.0 Introduction 1
2.0 Project Description 5
3.0 Project Organization 7
4.0 Quality Assurance Objectives 9
4.1 Precision, Accuracy, and Detectability 9
4.2 Completeness and Comparability 9
4.3 Representativeness 9
4.4 Samples Used to Monitor Data Quality 9
5.0 Sampling Strategy 15
5.1 Overall Sampling Strategy 15
5.2 Sampling Strategy for the Calibration Study 15
6.0 Field Operations 27
6.1 Activities of the Helicopter Sampling Crews 27
6.2 Activities of the Ground Sampling Crews 33
6.3 Field Base Operations 38
6.4 Training 42
7.0 Field Measurement Quality Control Checks 45
7.1 Quality Control Checks for Measurements Taken 45
by Helicopter Crews
7.2 Quality Control Checks for Measurements Taken 46
by Ground Crews
7.3 Field Laboratory Measurements 46
8.0 Analytical Procedures 47
9.0 Analytical Internal Quality Control 49
10.0 Performance and System Audits 51
10.1 Performance Audit Samples 51
10.2 Quality Assurance System Audits (On-Site Evaluations) 52
11.0 Acceptance Criteria 55
12.0 Data Management System 57
12.1 Data Set 1 - The Raw Data Set 57
12.2 Data Set 2 - The Verified Data Set 57
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Contents (continued)
Page
12.3 Data Set 3 - The Validated Data Set 58
12.4 Data Set 4 - The Final Data Set 59
13.0 Data Evaluation and Verification 63
13.1 Field Data Review 63
13.2 Analytical Data Review 64
14.0 Data Validation 69
15.0 Development of a Final Data Set 71
15.1 Missing Data Substitution 71
15.2 Averaging of Field Duplicate Pairs 71
15.3 Treatment of Negative Values 72
16.0 References 73
Appendix 75
VI
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List of Figures
Number Page
1-1 Timetable for field activities of the National Surface
Water Survey 2
3-1 National Surface Water Survey internal management
structure 7
4-1 Flow of quality assurance and quality control samples,
Western Lake Survey - Phase I 12
5-1 Subregions of the Western United States that are potentially
susceptible to acidic deposition. Western Lake
Survey - Phase I 16
5-2 Alkalinity map of the California subregion,Western Lake
Survey - Phase I 17
5-3 Alkalinity map of the Pacific Northwest subregion,
Western Lake Survey - Phase I 18
5-4 Alkalinity map of the Northern Rocky Mountain subregion,
Western Lake Survey - Phase I 19
5-5 Alkalinity map of the Central Rocky Mountain subregion,
Western Lake Survey - Phase I 20
5-6 Alkalinity map of the Southern Rocky Mountain subregion,
Western Lake Survey - Phase I 21
5-7 Sample flow for the calibration study, Western Lake
Survey - Phase I 23
5-8 National Surface Water Survey Form 2 - Batch QC Field Data 24
5-9 Preparation, identification, and shipment of sample batches
for the calibration study, Western Lake Survey - Phase I . . 25
6-1 Flowchart of sampling activities, Western Lake Survey -
Phase I 28
6-2 Flowchart of helicopter crew activities, Western Lake Survey -
Phase I 29
6-3 National Surface Water Survey Form 1 - Lake Data 30
6-4 Determination of temperature stratification class and lake
temperature profile, Western Lake Survey - Phase I 32
6-5 Field sample label, Western Lake Survey - Phase I 33
6-6 Aliquot label, Western Lake Survey - Phase I 34
6-7 Flowchart of ground crew activities, Western Lake Survey -
Phase I 35
6-8 National Surface Water Survey Sample Tracking and
Custody Form 37
6-9 Flowchart of daily field base activities, Western Lake Survey -
Phase I 39
6-10 Field audit sample label, Western Lake Survey - Phase I .... 39
6-11 National Surface Water Survey Form 3 - Shipping 43
12-1 Data management, Western Lake Survey - Phase I 58
14-1 Flowchart of the data validation process, Western Lake Survey -
Phase 1 69
15-1 Development of Data Set 4, Western Lake Survey - Phase I 72
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List of Tables
Number Page
1-1 Cross-References to Quality Assurance Subjects, Western
Lake Survey- Phase I 3
4-1 Data Quafity Objectives for Precision, Accuracy, and
Detectability, Western Lake Survey - Phase I 10
5-1 Variables Selected for Lake Classification, Western Lake
Survey - Phase I 15
6-1 Data Forms and Labels Used in the Field, Western Lake
Survey - Phase I 31
6-2 Sample Codes Used to Complete Lake Data Forms,
Western Lake Survey- Phase I 40
6-3 Aliquots, Containers, Preservatives, and Corresponding
Analyses, Western Lake Survey - Phase I 41
6-4 Split Sample Descriptions, Western Lake Survey - Phase I . . 41
9-1 Summary of Internal Quality Control Checks for Analytical
Methods, Western Lake Survey - Phase I 49
10-1 Desired Composition of Field Synthetic Audit Samples,
Western Lake Survey - Phase I 52
12-1 National Surface Water Survey Laboratory Field Data
Qualifiers (Tags) 59
12-2 Data Qualifiers (Flags) for the Verified Data Set, Western
Lake Survey - Phase I 60
13-1 Exception-Generating and Data Review Programs, Western
Lake Survey- Phase I 65
15-1 Validation Data Qualifiers (Flags) for the Final Data Set,
Western Lake Survey - Phase I 71
VIII
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Abbreviations^
AA
ANC
APHA
ASA
ASTM
BNC
CD
Cl
CRDL
DIG
DL QCCS
DOC
DQO
ELS-I
EMSL-LV
EPA
ERL-C
IBD
ICP
ID
IDL
IFB
IR
Lockheed-EMSCO
MIBK
NAPAP
NBS
NCC
NILS
NSWS
NTU
ORNL
PE
QA
QC
QCCS
RSD
RTP
SAS
atomic absorption spectroscopy
acid-neutralizing capacity
American Public Health Association
American Statistical Association
American Society for Testing and Materials
base-neutralizing capacity
conductance difference
confidence interval
contract-required detection limit
dissolved inorganic carbon
detection limit quality control check sample
dissolved organic carbon
data quality objective
Eastern Lake Survey - Phase I
Environmental Monitoring Systems Laboratory -
Las Vegas
Environmental Protection Agency
Environmental Research Laboratory - Corvallis
ion balance difference
inductively coupled plasma atomic emission
spectroscopy
identification
instrument detection limit
Invitation for Bid
infrared
Lockheed Engineering and Management
Services Company, Inc.
methyl isobutyl ketone
National Acid Precipitation Assessment Program
National Bureau of Standards
National Computer Center
National Lake Survey
National Surface Water Survey
nephelometric turbidity unit
Oak Ridge National Laboratory
performance evaluation
quality assurance
quality control
quality control check sample
relative standard deviation
Research Triangle Park
Statistical Analysis System
aThis list does not include units of measurement or chemical symbols.
IX
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Abbreviations (continued)
SMO - Sample Management Office
SOW -- Statement of Work
USGS -- United States Geological Survey
UV -- ultraviolet
WLS-I -- Western Lake Survey - Phase I
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Acknowledgments
The authors express their sincere appreciation for the valuable suggestions
provided by the following reviewers: David Peck (Lockheed Engineering and
Management Services Company, Inc.), Joseph Eilers and Susan Christie
(Northrop Services, Inc.), Lynn Creelman (Radian Corporation), Gordon
Bradford and Mohammed EI-Amamy (University of California, Riverside),
Michael Goggin and Richard Krebill (U.S. Department of Agriculture - Forest
Service), Wesley Kinney (U.S. Environmental Protection Agency), and Frank
Sanders (University of Wyoming). The assistance provided by the Lockheed
graphics department and the word processing staff at Computer Sciences
Corporation was essential to the completion of this document. Finally,
recognition belongs to Robert Schonbrod who has served as technical monitor
of this project.
XI
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1.0 Introduction
The National Acid Precipitation Assessment Program
(NAPAP) was initiated at the request of the
Administrator of the U.S. Environmental Protection
Agency (EPA) to evaluate the extent of the effects of
acidic deposition on aquatic resources within the
United States. When it became apparent that existing
data could not be used to assess quantitatively the
present chemical and biological status of surface
waters in the United States, the National Surface
Water Survey (NSWS) program was incorporated as
part of NAPAP to obtain that information. The National
Lake Survey (NLS) component of NSWS comprises
Phase I - Eastern Lake Survey (ELS--I), Phase I
- Western Lake Survey (WLS-I), and Phase II -
Temporal Variability (see Figure 1-1).
Data published in earlier studies are consistent with
the hypothesis that certain surface waters within the
United States have decreased in pH or alkalinity over
time. Acidic deposition has been suggested as a
contributor to such decreases. Also, numerous
studies have led to the conclusion that the effects of
acidic deposition on surface-water chemistry are
influenced by variations among lake, stream, and
associated watershed characteristics. Existing data
were compiled largely from numerous individual
studies. Extrapolating these data to the regional or
national scale was difficult because the studies often
were biased in terms of site selection. Additionally,
many previous studies were incomplete with respect
to the chemical variables of interest, were
inconsistent relative to sampling and analytical
methodologies, or were highly variable in terms of
data quality.
ELS-I, a synoptic survey of the chemistry of 1,612
lakes in the Eastern United States, was conducted to
obtain a regional and national data base of water
quality parameters that are pertinent to evaluating the
effects of acidic deposition. To provide a base of
information that is complete and consistent in terms
of the variables measured and the sampling and
analytical procedures used, ELS-I was carried out
on representative lakes in the Southeastern,
Northeastern, and Upper Midwestern regions of the
United States. Detailed sampling procedures (Morris
et al., 1986), standardized analytical protocols
(Hillman et al., 1986), and a rigorous quality
assurance (QA) program (Drouse et al., 1986) were
implemented, the purposes of WLS-I, a synoptic
survey of the chemistry of 757 lakes in the Western
United States, are parallel to those of ELS-I.
WLS-I was designed to minimize uncertainty in
making regional assessments based on existing data.
The five major design elements were as follows:
• Provide data from a subset of lakes that are
characteristic of the overall population of lakes
within a region.
• Use standardized methods to collect chemical
data.
• Measure a complete set of variables thought to
influence or to be influenced by surface-water
acidification.
• Provide data that can be used to investigate
statistical relationships among chemical
variables on a regional basis.
• Provide reliable estimates of the chemical status
of lakes within a region of interest.
The goals in designing WLS-I were to identify
objectives, develop an overall conceptual and
practical approach to meeting the objectives, identify
intended uses and users of the data, identify the
quality of data needed, develop an appropriate survey
design, develop analytical protocols and quality
assurance/ quality control (QA'QC) procedures, and
revise and modify approaches and methods as
needed. Thus, WLS-I was designed to provide
statistically comparable data that could be
extrapolated, with a known degree of confidence, to a
regional or national scale. The conceptual approach
emphasized that the data would not be used to
ascribe observed effects to acidic deposition
phenomena; rather, through comprehensive
monitoring activities, WLS-I would provide
information that could be used to develop correlative,
not cause-and-effect, relationships.
The conceptual approach to the program was
developed by EPA personnel and cooperating
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Figure 1-1 Timetable for field activities of the National Surface Water Survey.
National Surface Water Survey (NSWS)
I
National Lake Survey (NLS)
National Stream Survey (NSS)
Phase I - Synoptic Chemistry
Eastern Lakes (1984)
Western Lakes (1985)
Phase I - Synoptic Survey
Pilot Survey (1985)
Synoptic Survey (1986)
Southeast Screening (1986)
Episodes Pilot (1986)
Temporal Variability (1986-87) | j Episodic Effects (1988) [
scientists. Planning for WLS-I began in October
1983. The research plan for Phase I of the NLS was
initially reviewed late in 1983 by a large number of
scientists who have expertise in the areas of study.
Fifty scientists discussed the plan during a workshop
held in December; suggested modifications were
incorporated by March 1984. The research plan was
submitted to members of the American Statistical
Association (ASA) for review in June 1984; a final
ASA review was conducted in October 1984.
The QA plan and the analytical methods for WLS-I
are based on those used during ELS-I. The
analytical laboratory methods are identical for the two
surveys, but some field laboratory methods were
modified for WLS-I on the basis of ELS-I
experience and on the basis of constraints that
resulted from the special geographic limitations
associated with the high-altitude lakes in the West.
New field laboratory protocols also were added to
accommodate changes between ELS-I and WLS-I
field sampling methods. Sampling protocols are
significantly different in that ground access as well as
helicopter access is used to collect samples for
WLS-I (Bonoff and Groeger, 1987). The sampling
protocols differ from those used during ELS-I
because 400 of the WLS-I lakes are within
designated wilderness areas that are closed to
helicopter access. The ground sampling protocol
developed for use in sampling the restricted-access
lakes was first evaluated in a WLS pilot study
conducted by EPA Region VIII office in the autumn of
1984.
A specialized calibration study is included in WLS-I
to compare the effects of the two different sampling
methods on analytical results. The purpose of the
comparison is to derive calibration factors, if
necessary, that can be applied to data for samples
collected by ground crews so that these data will be
equivalent to data for samples collected by helicopter
crews.
EPA requires that data collection activities be based
on a program that ensures that the resulting data are
of known quality and are suitable for their intended
purpose. The purpose of a QA plan is to provide that
assurance. Therefore, EPA policy requires that every
monitoring and measurement project have a written
and approved QA project plan (Costle, 1979a and
1979b). This requirement applies to all environmental
monitoring and measurement efforts authorized or
supported by EPA through regulations, grants,
contracts, or other formal means. The QA project
plan should specify the policies, organization,
objectives, functional activities, and QA/QC activities
designed to achieve the data quality goals of the
project. All project personnel should be familiar with
the policies and objectives outlined in the QA project
plan to ensure proper interactions among the field
operations, laboratory operations, and data
management.
EPA guidance states that the 16 items shown in
Table 1-1 should be addressed in the QA project
plan (U.S. EPA, 1980). Some of these items are
addressed extensively in other manuals (Hillman et
al., 1986; Kerfoot and Faber, 1987; Morris et
al.,1985); therefore, as allowed by the guidelines,
these specific discussions are not repeated in this
document.
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Table 1-1.
Cross-References to Quality Assurance Subjects, Western Lake Survey -
Phase >a
Subject
Title Page
Table of Contents
Project Description
Project Organization and Responsibility
QA Objectives
Sampling Procedures
Sample Custody
Calibration Procedures
Analytical Procedures
Data Analysis, Validation, and Reporting
Internal QC Checks
Performance and System Audits
Preventive Maintenance
Assessment of Precision, Accuracy, and
Completeness
Corrective Actions
QA Reports to Management
Quality
Assurance
Plan
Contents
2
3
4
6
6
6
8
6, 9, 12, 13, 14
7,9
10
6
4,11
9,11
9,10
Field Operations
Report6
Field Sampling
Operations
Field Sampling
Operations
Field Sampling
Operations
Field Laboratory
Operations
Methods
Manualc
1
2
2, 3
2
4 to 13
3
3
2, 3
3
a The requirement to address these 16 QA subjects is stated in U S EPA (1980).
t> Bonoff and Groeger (1987).
c Hillman et al. (1986). Summary in Kerfoot and Faber (1987)
Quality assurance requirements and procedures that
were adopted verbatim from ELS-I are referenced
here and are described in detail in the ELS-I QA
plan (Drouse et al., 1986). ELS-I recommendations
that led to WLS-I protocol changes are discussed in
the ELS-I QA report (Best et al., 1987). The
sections that follow describe in detail only those QA
requirements and procedures that are specific to
WLS-I.
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2.0 Project Description
The WLS-I portion of NSWS is a synoptic survey of
757 lakes in the Western United States that will be
conducted during fall overturn. During this overturn
period, chemical variability within a lake is expected to
be minimal as a result of circulation within the water
column. WLS-I is designed to meet the following
objectives for designated regions of the Western
United States:
• Determine the percentage (by number and area)
and location of lakes that are potentially
susceptible to change as a result of acidic
deposition and that have low acid-neutralizing
capacity (ANC).
• Investigate the relationships among water
chemistry, regional acidic deposition patterns,
land use, physiographic features, lake
morphology, and basin geometry within and
among regions.
• Identify smaller subsets of representative lakes
for more intensive sampling in future surveys.
Of the lakes to be sampled during WLS-I, 455 lie
within designated wilderness areas. In order to
observe the guidelines and regulations set forth in the
Wilderness Act, almost all lakes located within
wilderness areas that have been selected for
sampling must be sampled by ground crews of the
U.S. Department of Agriculture - Forest Service.
The ground crews travel to lakes by foot or on
horseback. The lakes that are not in wilderness areas
are sampled by helicopter crews under the direction
of EPA.
Selected wilderness-area lakes that have been
determined to be inaccessible by ground crews are
sampled by helicopter crews during periods when
disturbance to wildlife or hikers is minimal. In addition,
45 wilderness-area lakes are sampled by ground
crews and by helicopter crews. The results for
samples collected from these 45 calibration lakes will
be used to evaluate the comparability of ground crew
and helicopter crew sampling protocols for collecting
and handling water samples.
This calibration study is designed to meet three goals:
• Quantify the differences between the two
sampling methods (helicopter and ground
access).
• Quantify the effects of holding samples for
different lengths of time prior to processing,
preservation, and analysis.
• Quantify any significant mterlaboratory bias
between the two analytical laboratories that
analyze WLS-I samples.
Data derived from the chemical analyses conducted
during the study will be used to establish calibration
factors that can be applied to analytical values
reported for all WLS-I samples. The calibration
factors are intended to eliminate value differences
that result from variations in sampling protocol,
sample holding time, or laboratory bias.
Two other studies are being conducted as part of
WLS-I. The purpose of one study, the nitrate/sulfate
stability study, is to compare sample preservation
methods and to study the effects of holding samples
for different lengths of time before preserving them.
The nitrate/sulfate sample is an extra aliquot taken
from the Van Dorn sampling unit, preserved with
HgCl2, and analyzed at the U.S. EPA Environmental
Monitoring Systems Laboratory - Las Vegas
(EMSL-LV). The purpose of the second study, the
Corvallis study, is to compare results for splits of the
same sample when the splits have been analyzed by
different methods. The analytical laboratories use
NSWS protocols for atomic absorption spectroscopy
(AA), inductively coupled plasma emission
spectroscopy (ICP), automated colorimetry, and ion
chromatography, according to the analyte; the
Environmental Research Laboratory at Corvallis,
Oregon (ERL-C), used ICP only and is not restricted
to the NSWS protocols and detection limits. A further
purpose of the Corvallis study is to determine if the
ICP data can be substituted in the data base if
problems arise with the standard analysis. Both
studies can provide checks on sampling, processing,
and analytical performance.
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-r «u » IA/I £> r _i ^ ^ tne survey and the effectiveness of this QA plan will
To ensure that WLS-f procedures are performed be tssuedyafter these factors have been evaluaPted.
consistently and that the quality of the data generated
can be determined, the QA project plan for WLS-I
specifies the following measures:
• Provide detailed, written sampling methodology
(Morris et al., 1985, and Peck et al., 1985;
summarized in Bonoff and Groeger, 1987).
• Simultaneously train and test all personnel
participating in field activities.
• Conduct on-site visits to each field operations
base and remote site soon after sampling
begins, and maintain daily telephone contact
throughout the sampling period to ensure that all
methods are being performed properly.
• Perform extensive evaluation of analytical
laboratories throughout their participation.
• Assess variability introduced at each level of
activity in field and analytical laboratories by
processing audit samples (synthetic and natural
lake samples), duplicate samples, and blank
samples along with routine samples. (Field
laboratory refers to the on-site mobile
laboratory that performs preliminary analyses
and aliquot preparation; analytical laboratory
refers to the off-site contract laboratory that
performs the more sophisticated analyses.)
• Provide detailed, written analytical methodology
(Hillman et al., 1986; summarized in Kerfoot and
Faber, 1987).
• Use internal QC procedures at the analytical
laboratory to detect potential contamination and
to verify established detection limits.
• Enforce holding-time requirements.
• Use protocols in the field and in the analytical
laboratory to confirm that reported data are
correct.
• Enter data from standardized data reporting
forms into the data base twice, and scan for
outlying values to eliminate effects of
transcription errors.
• Verify data by means of range checks, internal
consistency checks, and QA evaluations.
• Validate verified data by identifying values that
are not typical of values observed for the group
of lakes (e.g., stratum) from which the sample or
samples were drawn.
This QA plan is the final version of the draft plans that
were written before and were modified during WLS-I
activities. A QA report that describes the findings of
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3.0 Project Organization
Figure 3-1 illustrates the NSWS management
structure. The program director is the EPA official
who has overall responsibility for the program. The
responsibilities of the program manager, technical
director, and administrative coordinator are discussed
in detail in Drouse et al. (1986) as are the roles of the
Environmental Research Laboratory at Corvallis,
Oregon (ERL-C), the Environmental Monitoring
Systems Laboratory at Las Vegas, Nevada (EMSL-
LV), and the Oak Ridge National Laboratory (ORNL)
at Oak Ridge, Tennessee.
Figure 3-1. National Surface Water Survey internal management structure.
I Program Director
NAPAP Acid Deposition
I Program
Manager I
NAPAP Task
Technical
Director
Administrative
Coordinator
Peer Review
I
ERL-C
Sampling Design
Site Selection
Site Description
Data Validation
Data Interpretation
Reporting
I
EMSL-LV
Field Ope
and Loc
Analytics
QA/QC (
data ver
rations
sties
Methods
ncluding
ification)
ERL-C
and
ORNL
Data Management
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4.0 Quality Assurance Objectives
The statistical design, sampling and analytical
methods, and QA activities for WLS-I are structured
to meet specific data quality objectives (DQOs) for
the measurement of sampling, field laboratory, and
analytical laboratory performance. These DQOs are
designed to facilitate checking for chemical variability
and to provide confidence levels for reporting
population estimates.
4.1 Precision, Accuracy, and Detectability
The primary DQOs are measures of precision
(expressed as relative standard deviation), accuracy
(expressed as maximum absolute bias), and
detectabihty (expressed as an expected value range
and a required detection limit). These DQOs are
applied to each parameter measured at the lake
sampling site, in the field laboratory, and in the
analytical laboratory. Appropriate values and ranges
were established for each DQO (for each parameter
and measurement site) during ELS-I (Drouse et al.,
1986). The values and ranges used for WLS-I are
based on experience gained during ELS-I and on
standard laboratory QA/QC requirements. Table 4-1
summarizes the primary DQOs used for WLS-I;
further discussion can be found in Drouse et al.
(1986).
4.2 Completeness and Comparability
Certain other DQOs also have been considered in the
survey design. Completeness (the quantity of
acceptable data actually collected in relation to the
total quantity that is expected to be collected) is set
at 90 percent or better for all variables, on the basis
of experience gained during ELS-I. Comparability (a
measure of the confidence with which one data set
can be compared to another) is ensured by requiring
that standard procedures be used for laboratory
analyses and that a uniform set of units be used for
reporting data. The calibration study was performed to
ensure that differences in the sampling and on-site
analytical procedures used by helicopter crews and
ground crews did not reduce data comparability.
4.3 Representativeness
Representativeness (the degree to which data
accurately and precisely represent a characteristic of
a population) is an important concern of IMSWS. The
sampling scheme for WLS-I was designed to
maximize representativeness. A systematic random
sample drawn within strata ensured good
geographical coverage without bias (Landers et al.,
1987).
WLS-I is not intended to characterize the chemistry
of any given lake spatially or temporally. Therefore,
achieving WLS-I objectives does not require that the
only sample taken from a lake be completely
representative of the lake. In most cases (except for
the lakes to be sampled during the calibration study)
only one sample per lake is taken during WLS-I. A
determination of whether one sample per lake is
sufficient to achieve the general objectives of NSWS
Phase I, however, can be made from estimates of
" withm-lake" and "among-lakes" variances.
Although some estimates of these variances will be
made for WLS-I lakes in accordance with the
statistical sampling design, future, more intensive
studies of individual lakes will provide more complete
data on representativeness.
Although the individual sample is not necessarily
representative of the lake, the subset of lakes
sampled should be representative of the sub-
regional or regional population of lakes. The
systematic sampling design that was adopted for this
survey is intended to ensure representativeness at
this level.
4.4 Samples Used to Monitor Data Quality
Several types of QA and QC samples are used to
ensure that sampling and analytical methods are
performed according to the NSWS Statement of Work
(SOW) and this QA plan (Figure 4-1). QA samples
are used by the QA staff to evaluate overall method
performance for field sampling, field laboratory
procedures, and analytical laboratory procedures and
to evaluate overall data quality for the survey. QC
samples allow field samplers and personnel at the
field and analytical laboratories to identify and correct
local problems (e.g., providing the analyst with
immediate feedback on reagent contamination or
questionable instrument performance). The use of QC
samples in the field is discussed in Section 7 of this
document; QC samples and procedures for the
-------
Table 4-1. Data Quality Objectives for Precision, Accuracy, and Detectability, Western Lake Survey - Phase I
Site3
2, 3
2, 3
3
3
3
3
1, 3
2, 3
3
3
3
3
3
3
3
3
3
Parameter6
Al,
Extractable
Al, Total
ANC
BNC
Ca
Cl"
Conductance
DIC
DOC
F", Total
dissolved
Fe
K
Mg
Mn
Na
NH4 +
N03
Method
Extraction with 8-
hydroxyquinoline
into MIBK followed
by AAe (furnace)
AAe (furnace)
Titration and Gran
analysis
Titration and Gran
analysis
AAe (flame) or
ICP9
Ion chromatography
Conductivity cell
and meter
Instrumental
(acidification, CC>2
generation, IR
detection)
Instrumental (UV-
promoted oxidation,
CC>2 generation, IR
detection)
Ion-selective
electrode and meter
AAe (flame) or
ICP9
AAe (flame)
AAe (flame) or
ICP9
AAe (flame) or
ICP9
AAe (flame)
Automated
colonmetry
(phenate)
Ion chromatography
Units
mg/L
mg/L
ueq/L
(jeq/L
mg/L
mg/L
US/cm
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
Expected
Range0
0.005 - 1.0
0.005 - 1.0
-100 -
1,000
-10 - 150
05-20
02-10
5 - 1,000
0.05 - 15
0.1 - 50
0.01 - 02
0.01 - 5
01-1
01-7
0.01 - 5
0.5 - 7
001-2
001-5
Required
Detection
Limits
0.005
0.005
f
f
0.01
0.01
h
005
0.1
0.005
0.01
001
0.01
0.01
0.01
0.01
0.005
Precision
Relative Standard
Deviation (RSD)
Upper Limit (%) <*
10 (Al cone.
>0.01)
20 (Al cone
<001)
10 (Al cone
>001)
20 (Al cone
<001)
10
10
5
5
2
10
5 (DOC cone
>5)
10 (DOC cone
<5)
5
10
5
5
10
5
5
10
Accuracy
Max. Absolute
Bias (%)
10
20
10
20
10
10
10
10
5
10
10
10
10
10
10
10
10
10
10
(continued)
analytical laboratories are discussed in Section 9 of
Drouse et al. (1986). The types of QA and QC
samples to be used during WLS-I are described in
subsections 4.4.1 and 4.4.2.
4.4.1 Quality Assurance Samples
QA samples that are introduced in the field or at the
field laboratory are analyzed at the field laboratory
and at the analytical laboratory. These samples are
used to judge the overall performance of WLS-I
sampling and analytical activities and to establish data
quality. The QA samples are "double blind" to the
analytical laboratories (i.e., the laboratories do not
know the origin, identity, or composition of the
samples). Consequently, the analytical laboratories
process QA samples as they would any other
routinely analyzed sample. The QA samples used are
(1) field blanks, (2) trailer blanks, (3) field duplicates,
and (4) field audits.
• Field Blank -
A field blank, which is prepared at the field
laboratory, is a deionized water sample that
10
-------
Table 4-1 (Continued)
Sitea Parameter*3
Method
Units
Precision
Required Relative Standard Accuracy
Expected Detection Deviation (RSD) Max. Absolute
Range0 Limits Upper Limit (%)d Bias (%)
1,2 pH, Field pH electrode and
meter
PH
units
3 pH, Analytical pH electrode and pH
laboratory meter units
P, Total
SiO2
SO42"
True color
Turbidity
Automated
colorimetry
(phospho-
molybdate)
Automated
colorimetry
(molybdate blue)
Ion mg/L
chromatography
Instrument MTU*
(nephelometer)
3-8
3 - 8
mg/L 0 005 - 0.07
mg/L 0 1 - 25
1 - 20
0002
0.05
005
±0.1'
±0.05'
10 (P cone.
20 (P cone.
Comparison to PCU/ 0 - 200
platinum-cobalt
color standards
2 - 15
±5'
10
±0.1'
±005'
10
20
10
10
10
a 1 = lake site, 2 = field laboratory, 3 = analytical laboratory
b Dissolved ions and metals are being determined, except where noted
c Ranges are for lake waters.
d Unless otherwise noted, this is the %RSD at concentrations greater than 10 times required detection limits
6 AA = atomic absorption spectroscopy
f Absolute blank value must be < 10.
9 ICP = inductively coupled plasma atomic emission spectroscopy
h Blank must be < 0 9 tiS/cm
' Absolute precision goal in terms of applicable units.
American Public Health Association platinum-cobalt units.
* Nephelometnc turbidity units
meets specifications of the American Society for
Testing and Materials (ASTM) for Type 1
reagent-grade water (ASTM, 1984). The
sampling crew transports the blank water to the
lake in Cubitainers and processes the blank
through the Van Dorn sampler as if the blank
were a lake sample. Because the action of
pouring the blank water through the Van Dorn
sampler creates the possibility of changing the
C02 concentration in the sample, which would
affect the pH and DIG field measurements, pH
and DIG syringe samples are not taken for the
field blanks. True color and turbidity, however,
are determined for each field blank at the field
laboratory. Each helicopter crew collects one
field blank on each operating day; each ground
crew collects two field blanks during the course
of the survey.
Field blanks are inserted in the sample batches
that are sent to the analytical laboratories. They
are used to identify contamination problems that
may occur during the sampling and analytical
processes and to provide data that are used to
establish the estimated system decision limit,
quantitation limit, and background levels that
could be expected for each variable. For data
interpretation, any data point above the expected
value for the blank is considered to be a positive
response for a given analyte.
• Trailer Blank -
The trailer blank is used instead of a field blank
when a field blank is not collected for a
particular sample batch. The sampling design of
WLS-I occasionally results in situations in
which a field blank is not scheduled to be
processed at any lake site for a particular
sampling day. When this situation occurs, a
deionized water sample is processed in the field
laboratory as if it were a field blank that has
been delivered to the field laboratory by the
sampling crew. The chief difference between the
11
-------
Figure 4-1. Flow of quality assurance and quality control samples, Western Lake Survey - Phase I.
Field
Samplers
X
I Field Blank I k
Field
Laboratory
1
Trailer Blank
(in Lieu of
Field Blank)
Contract
Laboratorry
ki Fieln1 Blink 1
Field Duplicate
Field Duplicate
Trailer Duplicate
(Split of a randomly
selected routine
lake sample)
QCCS
Hydrolab pH, Cond
Natural
Audits
Lake Superior
(FN3)
Big Moose Lake
(FN4)
Bagley Lake
(FN5, FN6)
Field Audits
QCCS
pH, DIC, Turbidity
Audit Sample
Preparation Laboratory
Prepared Natural Audits
(FN3, FN4, FN5, FN6)
and Synthetic Audits
(FL 11, FL 12)
Calibration Blank
DIC
Field Duplicate I
Field Audits
QCCS
(Form 20)
Calibration/
Reagent Blank
(Form 20)
Matrix Spike
(on Field Sample)
(Form 21)
Laboratory
Duplicate
(Split of Field
Sample) (Form 22)
two types of blanks is that the trailer blank is
never processed through the Van Dorn sampler.
The trailer blank is then inserted (in place of a
field blank) in the sample batch that is sent to
the analytical laboratory.
• Field Duplicate -
A field duplicate is a second sample collected at
the lake site immediately after the routine
sample is collected. The field duplicate is
collected by the same sampling crew that
collects the routine sample; the same procedure
is used to collect both samples. For each field
base, one helicopter crew collects a field
duplicate on each sampling day. Each ground
crew collects two field duplicates during the
course of the survey. Field duplicates are
processed by the field laboratory and are
inserted as double-blind samples in the sample
batches that are sent to the analytical
laboratories.
Field routine/duplicate pairs are used to
determine the precision of the field samplers'
technique in sampling, the precision of the field
laboratory in analyzing and processing samples,
and the precision of the analytical laboratory in
analyzing samples. The routine/duplicate pair is
also used to determine the homogeneity of the
lake sample.
NOTE: Duplicate samples that are collected for
the calibration lake study are not used
as QA samples because sampling
methods, holding times, and batches
differ for the five comparable samples
collected from one lake (routine and
duplicate collected by the ground crew
and routine, duplicate, and triplicate
12
-------
collected by the helicopter crew). See
Section 6 for a discussion of calibration
study procedures.
• Field Audits -
Two types of audit samples (field natural audit
samples and field synthetic audit samples) are
used to establish overall field and analytical
laboratory performance. A third type of audit
sample, a laboratory audit, which was used for
ELS-I, is not being used for WLS-I. ELS-I
results showed that the practical significance of
the difference in precision between laboratory
audits and field audits was negligible; therefore,
the use of laboratory audits was determined not
to be cost effective.
Field natural audit samples are composed of
natural lake water; field synthetic audit samples,
which are prepared to simulate natural lake
water, are reagent-grade water that contains
the analytes of interest at specified theoretical
concentrations.
Field audit samples are used (1) to determine
the relative bias between analytical laboratories,
so that measurements made by the two
laboratories can be compared and (2) to indicate
precision of those measurements through
repeated analysis of the same sample type.
Both types of field audit samples are received in
2-L portions from a central source; at the field
laboratory, the samples are filtered and
preserved. Aliquots are taken from the filtered
audit samples as from routine lake samples, and
these aliquots are shipped to the analytical
laboratory as double-blind samples.
Only low-concentration synthetic audit samples
are used for this survey. High-concentration
synthetic samples are not utilized because
concentrations of analytes in WLS-I lakes are
anticipated to be low.
4.4.2 Quality Control Samples
4.4.2.1 Hydrolab Quality Control Samples-
Quality control check samples (QCCSs) are used by
the helicopter crews to check Hydrolab pH and
conductance measurements in the morning (prior to
sampling activity) and in the evening (after sampling
activity is completed for the day). The morning
QCCSs are used to check the calibration of the
Hydrolab; the evening QCCSs indicate instrument
drift over time.
4.4.2.2 Field Laboratory Quality Control
Samples--
Three types of QC samples are used by the field
laboratory staff to ensure that instruments and data
collection are within specified control limits. The QC
samples are (1) calibration blanks, (2) QCCSs, and
(3) trailer duplicates.
• Calibration Blank - A calibration blank
(deionized water drawn directly from the water
purification unit located in the field laboratory) is
used to check for baseline drift of the carbon
analyzer and to check for contamination. The
calibration blank is analyzed prior to sample
analysis for dissolved inorganic carbon (DIG).
• Quality Control Check Sample - QCCSs are
prepared in the field laboratory or are
purchased. They are used to check initial
instrument calibration and, during sample
analysis, to check at specified regular intervals
for instrumental drift. QCCSs are analyzed for
pH, DIG, and turbidity. The QCCS for pH is a
0.0001 N H2SO4 solution with a pH of 4.0; for
DIG, QCCSs of 2 mg L and 20 mg L NapCOa
are prepared; for turbidity, the QCCSs are
turbidity standards of 10.00, 20.00, 100.00, and
200.00 nephelometric turbidity units (NTU).
• Trailer Duplicate - The trailer duplicate, a
second measurement of a routine sample, is
used to check the precision of measurements
made in the field laboratory. The field laboratory
supervisor randomly selects one lake sample
per trailer operating day; this sample is analyzed
in duplicate for pH, DIG, true color, and turbidity.
4.4.2.3 Analytical Laboratory Quality Control
Samples--
Six types of QC samples are used by the analytical
laboratories to ensure that instruments and data
collection are within control limits. These six sample
types are (1) calibration blanks, (2) reagent blanks,
(3) detection limit QCCSs, (4) low-concentration and
high-concentration QCCSs, (5) matrix spikes, and
(6) laboratory duplicates. The sources, compositions,
and concentration ranges of these QC samples are
described in Hillman et al. (1986).
• Calibration Blank - For each sample batch, the
analytical laboratory must analyze one calibration
blank for each required analyte. For each
analytical procedure, the calibration blank, which
is a 0-mg L standard, is analyzed after the
initial instrument calibration to check for drift in
the measured signal and to check for potential
contamination during the analytical process. The
observed analyte concentration for the
calibration blank must not exceed twice the
13
-------
contract-required detection limit (CRDL) for intralaboratory precision limits established for
that analyte. these variables (see Table 4-1).
• Reagent Blank - A reagent blank is required for
dissolved SiC>2 and total aluminum analyses
because additional reagents are added during a
digestion step prior to analysis. The reagent
blank comprises all the reagents (in the same
volumes) used in preparing a lake sample for
analysis. The reagent blank and lake samples
are carried through the same preparation steps
(e.g., digestions) prior to analysis. Values
obtained for the reagent blank must not exceed
twice the CRDL for the analyte.
• Detection Limit Quality Control Check Sample -
A detection limit QCCS (DL QCCS) is also
analyzed for required variables. The DL QCCS
is used to determine and verify the low end of
the calibration curve and the values for the
low-level samples that are near the detection
limits. The DL QCCS concentration must be
between 2 and 3 times the CRDL. The DL
QCCS is analyzed once, prior to regular sample
analysis.
• Low-Concentration and High-Concentration
Quality Control Check Samples - The analytical
laboratory QCCS is a commercially or
laboratory-prepared sample that is prepared
from a stock solution different from the one that
is used to prepare the calibration standards. The
QCCS is analyzed to verify calibration at the
beginning of sample analysis, after each
specified number of sample analyses, and after
the final sample in the batch is analyzed. The
observed concentrations must be within the
specified control limits.
• Matrix Spike - A matrix spike, which is
analyzed for specified analytes in each sample
batch, is a check to determine the level of
analytical interference that is caused by the
matrix of the water sample on a particular
analyte. The analyst "spikes" (i.e., enriches) an
aliquot of sample with a known quantity of an
analyte and then analyzes the spiked and
unspiked samples. The percentage of spiked
analyte recovered (percent recovery) is then
calculated to determine whether or not there is a
matrix effect on the analytical value of the
original sample.
• Laboratory Duplicate - An analytical laboratory
duplicate is required for each batch of samples.
A duplicate analysis is performed on one sample
for each required variable in each batch to
establish within-laboratory precision. The
observed precision must meet the required
14
-------
5.0 Sampling Strategy
5.1 Overall Sampling Strategy
The sampling strategy for selecting NSWS lakes is
discussed in detail in Landers et al. (1987) and is
summarized in Drouse et al. (1986).
The lakes are selected by means of a systematic,
stratified design. There are three stratification factors:
regions, subregions, and alkalinity classes (see Table
5-1). Each stratum is an alkalinity class within a
sub- region within a region. In the Western United
States (defined as NLS Region 4) all three alkalinity
classes are found within each of the five subregions
designated 4A through 4E, so the total number of
strata in WLS-I is fifteen. Figures 5-1 through 5-6
depict the region, subregions, and alkalinity classes
the strata comprise.
Table 5-1. Variables Selected for Lake Classification,
Western Lake Survey - Phase I
Level
Divisions within Levels
Region
Subregion
Alkalinity Class
Western United States
4A, California
4B, Pacific Northwest
4C, Northern Rocky Mountains
4D, Central Rocky Mountains
4E, Southern Rocky Mountains
1. Alkalinity < 100neq/L
2 Alkalinity 100 to 200
3. Alkalinity >200 neq/L
5.2 Sampling Strategy for the Calibration
Study
As a part of the overall WLS-I sampling and
analytical strategy, 45 of the 455 wilderness-area
lakes being studied are included in a calibration study.
Legislation restricts activities that jeopardize the
pristine character of wilderness areas, and
considerable precedent has been established to limit
helicopter and other motorized access to such areas.
However, because information obtained from WLS-I
might be of great help in long-term maintenance of
wilderness characteristics, the Forest Service
approved helicopter access to the 45 lakes so that
the established sampling method (by helicopter) could
be compared to the new method (ground access).
Each calibration lake is sampled by one helicopter
crew and by one ground crew. The two crews collect
samples from approximately the same location (the
deepest spot) on the lake. The ground crew samples
the lake from a boat, then the helicopter crew
samples the lake as soon as possible thereafter
(optimally, within 1 hour). The ground crew collects a
routine sample and a duplicate sample; the helicopter
crew collects a routine sample, a duplicate sample,
and a triplicate sample. Both types of sampling crews
use standard WLS-I sample collection techniques.
Because collecting samples by ground access is a
new protocol, it is important to be certain that this
protocol is applied uniformly to all WLS-I lakes. To
ensure that each ground crew's sampling procedure
is representative of the sampling done at all WLS-I
lakes, the ground crews are not told (i.e., they are
"blind" to) which lakes are calibration lakes. The
helicopter sample collection procedure is a proven
protocol that was tested during ELS-I; therefore, it is
not necessary for the WLS-I helicopter crews to be
blind to the identity of calibration lakes.
The logistics of the sampling design raised the
possibility that the ground samples might arrive at the
field laboratory 1 to 5 days after they were collected.
Therefore, the possible effects of delayed sample
preservation (or "holding time") are of interest. Three
processing procedures have been developed to allow
for possible delays in delivering samples from the
lake site to the field laboratory and to allow the effects
of different holding times to be observed. Each
procedure assumes a different relationship between
the sampling and arrival times of the helicopter crew's
samples and the ground crew's samples.
For each of the three processing procedures, the field
laboratory preserves the ground crew's samples on
the collection date (or on the date the samples arrive
at the field laboratory) and preserves two of the
helicopter crew's samples on the collection date. The
third sample collected by the helicopter crew is not
preserved on the collection date Instead, this sample,
which is randomly selected from among the three
samples collected by the helicopter crew, is held at
the field laboratory for a specified length of time
15
-------
Figure 5-1. Subregions of the Western United States that are potentially susceptible to acidic deposition. Western Lake
Survey - Phase I.
Northern Rocky
Mountains (4C)
Pacific
Northwest (4B)
California (4A)
Central
Rocky j
Mountains (40)
Southern Rocky
Mountains (4E)
Subregion Boundary
16
-------
Figure 5-2. Alkalinity map of the California subregion. Western Lake Survey - Phase I.
OR
CD < 100
t3 100 to 200
>200
Alkalinity Classes
(/ueq/L)
Subregion Boundary
17
-------
Figure 5-3. Alkalinity map of the Pacific Northwest subregion. Western Lake Survey - Phase I.
Alkalinity Classes
(Aieq/L)
CD <100
[3 100 to 200
[3] >200
Subregion Boundary
18
-------
Figure 5-4. Alkalinity map of the Northern Rocky Mountain subregion. Western Lake Survey - Phase I.
Alkalinity Classes
(//eq/L)
<100
100 to 200
>200
Subregion Boundary
19
-------
Figure 5-5. Alkalinity map of the Central Rocky Mountain subregion. Western Lake Survey - Phase I.
Alkalinity Classes
(Aieq/L)
Q] <100
[2] 100 to 200
LI >200
Subregion Boundary
UT
CO
20
-------
Figure 5-6.
Alkalinity map of the Southern Rocky Mountain subregion. Western Lake Survey - Phase I.
X
s Alkalinity Classes
/ (yueq/L)
/Pv^ CO 200
i Subregion Boundary
21
-------
before it is preserved. The holding time imposed on
the withheld sample depends on which of the three
processing procedures is applied.
The calibration study has also been designed to
provide data that can be used to evaluate
interlaboratory bias. To meet this goal, the field
laboratory sends one sample from each
routine/duplicate pair collected by a ground crew and
one sample from each routine duplicate triplicate set
collected by a helicopter crew to each analytical
laboratory.
The remaining sample from each set collected by
helicopter is the one that is withheld at the field
laboratory for later processing and preserving; the
assignment of a sample (routine, duplicate, or
triplicate) to a particular analytical laboratory is made
randomly and individually for every pair or set of
samples. Figure 5-7 illustrates the sample
assignment procedure that is used.
Specific sample codes are recorded on NSWS Form
2 - Batch/QC Field Data, Figure 5-8, (1) to
distinguish the calibration lake samples from the
routine lake samples, (2) to distinguish samples
collected by the helicopter crews from samples
collected by the ground crews, and (3) to distinguish
helicopter samples withheld for later processing from
samples processed on the day of sample collection.
Samples collected by the ground crews are coded
RGC (routine ground calibration) and DGC (duplicate
ground calibration). The samples collected by the
helicopter crews are coded RHC (routine helicopter
calibration), DHC (duplicate helicopter calibration),
and THC (triplicate helicopter calibration) on the
batch/QC form. A "W" is added after the last letter of
one of the helicopter sample codes to indicate that
the sample is being withheld (e.g., if the RHC sample
is withheld, it is coded RHCW on the batch form).
When the calibration lake samples collected by the
helicopter crew arrive at the field laboratory, they are
separated into batches, are assigned identification
(ID) numbers, and are shipped to the analytical
laboratory. This process is shown in Figure 5-9. The
laboratory coordinator uses the random selection
procedure mentioned above to determine (1) which
sample to withhold at the field laboratory (at 4 °C in
the dark), (2) which samples to process with the
corresponding samples collected by the ground crew,
and (3) which analytical laboratory analyzes each
sample.
Thus, the five samples collected from a single
calibration lake are processed in three different
batches: one sample collected by the helicopter crew
and one sample collected by the ground crew are
incorporated in the sample batch that is sent to the
"regular" analytical laboratory (the laboratory to which
the field base ships its usual, daily sample batch).
One sample collected by each crew is incorporated
into the sample batch that is sent to the "alternate"
analytical laboratory (the laboratory used regularly by
another field base). The last sample (the withheld
sample designated from among the samples collected
by the helicopter crew) is kept at the field base for
incorporation into a sample batch shipped on a
different day.
Calibration lake samples that are incorporated in the
daily sample batch to be shipped to the regular
analytical laboratory receive appropriate batch and
sample ID numbers. A complex batch and sample
numbering scheme is necessary to enable calibration
samples to be associated with their QA samples in
the data verification step. For the two or three
calibration lake samples that constitute a batch that
will be sent to the alternate laboratory, the laboratory
coordinator obtains batch and sample ID numbers
from the laboratory coordinator at a second field
base; these numbers correspond to the batch that the
second field laboratory is processing that day. This
second field laboratory is called the "reference" field
laboratory, and it, in turn, uses the alternate analytical
laboratory of the first field laboratory as its regular
analytical laboratory.
This cross-laboratory procedure allows the two or
three samples destined for the alternate analytical
laboratory to be incorporated into the larger daily
sample batch from the reference field laboratory when
the shipments from the two field laboratories are
received. In this way, the two or three samples do not
constitute a separate batch and, thus, do not have to
be accompanied by a separate set of field blank and
audit samples.
To obtain the batch and sample ID numbers for the
calibration lake samples that are to be sent to the
alternate analytical laboratory, the field laboratory
coordinator calls the laboratory coordinator at the
appropriate reference field laboratory. The reference
laboratory coordinator assigns the sample ID numbers
in order, according to the order of phone calls
received from the requesting field laboratories.
The laboratory coordinator who is preparing the
samples for shipment fills out a separate batch/QC
form for the calibration samples that will be shipped to
the alternate analytical laboratory. This form shows
the batch ID assigned by the reference laboratory.
Field laboratory data for each calibration sample are
entered on the line of the batch/QC form that
corresponds to the assigned sample ID. The
reference field laboratory coordinator should note in
the comment section on the batch/QC form which
22
-------
Figure 5-7. Sample flow for the calibration study. Western Lake Survey - Phase I.
Ground Samples
(Forest Service)
Helicopter Samples
(Lockheed-EMSCO, EPA)
Routine
1st
Sample
Taken
I
RGC
{
Duplicate
2nd
Sample
Taken
DGC
1
Routine ^ Duplicate ^ Triplicate
1st 2nd 3rd
Sample Sample Sample
Taken Taken Taken
L RHC DHC THC
i '
Field Laboratory
\
WW
1 J , I
RGC
7
Aliquots
DGC
7
Aliquots
RHC DHC THC
777
Aliquots Aliquots Aliquots
' Randomly Selected T
L Sample Shipment 1
I ."
I I
I I
t t
Analytical
Laboratory
1 1
._J I
I I
__J I
I I
t t
Alternate
Analytical
Laboratory
Legend
RGC-Routme Ground Calibration
DGC-Duplicate Ground Calibration
RHC-Routine Helicopter Calibration
DHC-Duphcate Helicopter Calibration
THC-Triphcate Helicopter Calibration
23
-------
Figure 5-8. National Surface Water Survey Form 2 - Batch/QC Field Data.
National Surface Water Survey
Form 2
Batch/QC Field Data
Date Received
By Data Mgt
Entered
Re-Entered —
Batch ID
Lab to Which
Batch Sent _
No Samples
in Batch
Base Site ID .
Date Shipped
Lab Crew ID _
Date Processed -
Air-Bill No
Field Laboratory
Supervisor
Field
Crew
ID
Lake
ID
(XXX-XXX)
Sample
Code
OIC(mg/LI
QCCS Limits
UCL—2 2
LCL—1 8
Value QCCS
Statoin pH
QCCS Limits
UCL—4 1
LCL—3 9
Value QCCS
Turbidity (NTU)
QCCS Limits
UCL—5 5
LCL—4 5
Value
QCCS
Color
(APHA
Units)
Value
Split
Codes
(EU
Comments
White—ORNL Copy Yellow—Field Copy Pink—EMSL-LV Copy
24
-------
Figure 5-9.
Preparation, identification, and shipment of sample batches for the calibration study. Western Lake Survey
Phase).
Regular
Analytical Laboratory
Samples Received
i and
Analyzed Normally
Alternate
Analytical Laboratory
Shipment from
Both Field
Laboratories
Combined into
One Field Batch
and Analyzed
Normally
1 Normal Lake •
Samples • "
\- J
0<\ -^-$1.
tf^XN,^
G'^X>ielicoptervv%/s,
^^ Samples ^O
^X. 2 Ground y^
^s^amples^^
<
L »
c 'AT 7
o ^ w
Principal
Field Laboratory
• Calibration Lake
Samples (3 of 5)
from Normal Sample
Batch
• Reference Field (|
Laboratory
Coordinator Called
for "Borrowed" Batch
ID and Two Sample ID
Numbers
Sample from Each
Calibration Lake
Withheld for Future
Processing
c/»
f/S
/A?
J
*l
I
Reference
Field Laboratory
• Reference Field '
Laboratory in
Normal Sample
Processing Mode
IPR
• Two Sample IDs frorr
Day's Batch "Lent" t
Principal Field
Laboratory
"o
i
0
H Normal Lake .
Samples '
25
-------
sample ID numbers were assigned to the other field
laboratories for calibration samples. Explanation of the
qualifier should be in the comments section of the
batch/QC form.
26
-------
6.0 Field Operations
Field operations are coordinated at field bases under
the supervision of an EPA field base coordinator.
Each field base contains a mobile field laboratory that
is operated by a five-person crew. One or two
helicopter crews operate from each field base through
an EPA duty officer. Each helicopter crew makes one
or more excursions to lake sites each day. Ten to
fifteen ground crews operate from each base site
through a Forest Service field manager. Each
helicopter crew samples as many as 10 lakes per
day, and each ground crew samples 1 or 2 lakes per
day (or per excursion). The field base coordinator and
the field manager coordinate lake sampling so that no
more than 30 field samples are processed at a field
base on any day to prevent an overload of samples
arriving at the analytical laboratories.
Sections 6.1 through 6.3 describe the activities of the
helicopter crews, the ground crews, and field base
crews. Bonoff and Groeger (1987) provide a further
description of field operations. Section 6.4 of this QA
project plan refers to the field personnel training.
Quality control checks for field measurements are
presented in Section 7. Figure 6-1 depicts the flow
of samples and data forms for WLS-I.
6.1 Activities of the Helicopter Sampling
Crews
Activities that are conducted by the helicopter crews
during WLS-I are similar to those conducted during
ELS-I. Each helicopter crew consists of a pilot, an
observer, a sampler, and a support person who
remains at the field base. The observer's
responsibility is to ensure that all measurements and
sampling operations are performed correctly and that
data are recorded accurately. The sampler must be
qualified to operate all equipment and must follow
prescribed procedures. For each excursion, the
activities of each helicopter crew are divided into
three sections: (1) activities at the field base prior to
sampling, (2) activities en route to or at the lake site,
and (3) activities at the field base after the sampling
day is completed. These activities are described in
the following three subsections. A flowchart of
helicopter field crew activities is shown on page 29
(Figure 6-2).
6.1.1 Field Base Activities Conducted Prior to
Sampling
Before leaving the field base, the helicopter crew
must perform the following tasks:
• Prepare a detailed navigation sheet that gives
courses and distances for the excursion and
the navigational coordinates of each lake to
be sampled. Preliminary information about a
lake, such as latitude, longitude, and name, is
supplied by ERL-C and local authorities. If
possible, the location of the deepest part of
each lake is predetermined (i.e., interpolated
from topographic maps) and is indicated on a
map as the preferred sampling site.
• File a flight plan with the field base
coordinator so that sample arrival time can be
predicted and so that safety requirements can
be met. (Any deviations from the flight plan
that occur during an excursion are relayed
immediately to the field base coordinator.)
• Calibrate the Hydrolab unit, which is used to
obtain pH, conductance, and temperature
profiles of each lake. Hydrolab calibration data
are recorded on the Hydrolab calibration form.
• Using a checklist, ensure that all the required
supplies are on hand. The crew packs the
supplies and loads the helicopter.
While the helicopter crew performs these operations,
the pilot must carry out the following activities:
• Calibrate and program the loran-C.
• Confer with the mechanic about maintenance
checks and possible refueling stops.
Once these steps are performed, the helicopter
proceeds to the lake.
6.7.2 Lake Site Activities
As the helicopter approaches a lake, one crew
member takes photographs of the area. Preceding
each set of lake photographs, a photograph is taken
27
-------
Figure 6-1. Flowchart of sampling activities, Western Lake Survey - Phase I.
Field Sampling Sites
Audit Sample
Preparation
Laboratory
Transf
toF
Labor
at 4
•>
)orted
eld
atory
°C
r
Field
Laboratory
^ Samples
7 Organized
into Batch
Shipped
to Field
Laboratory
at4°C
^
r
f
+
Closed-
System
PH
i
4r
Turbidity
Measured
^
r
r
True Color
Measured
^
Aliqi
Prep.
an
u^
at 400
Data
Transcribed
to Data Forms
Next Day
Next Day
Copies of Lake
Data and Batch
Forms Sent to
Data Management
Center and
Qual ty Assurance
Personnel
Al quots Shipped
to
Analytical
Laboratory
with Shipp ng Form
Copy of Sh pping
Form Sent to
Sample
Management
Office and
Quality Assurance
Personnel
of a card (lap card) that shows the date, the lake ID
number, the lake name, and the crew ID. These
photographs are useful as an additional check in
verifying that the correct lake was sampled. After the
photographs are taken, the photograph frame
numbers are written on Form 1 - Lake Data, which
28
-------
Figure 6-2. Flowchart of helicopter crew activities, Western Lake Survey - Phase !
Activities Conducted
at Field Base
before Departure
1. Prepare Site Description.
2. Calibrate Hydrolab.
3. Check List of Supplies
for Day's Sampling.
4. Load Helicopter.
5. Check List of Lakes to be
Sampled, and File Flight Plan
with Field Base Coordinator
No
Activities Conducted
at Field Base
after
Sampling Excursion
1. Unload Samples.
2. File Lake Data Forms with
Field Base Coordinator.
3. Transfer Samples to
Laboratory Coordinator;
Jointly Check Lake ID and
Number of Cubitainers and
Syringes.
4 Check Hydrolab Calibration
and Perform Required
Equipment Maintenance.
Activities Conducted
at Lake Site
1 Take Aerial Photographs
2. Verify Lake Identity.
Activities Conducted
on Lake
1. Measure Site Depth.
2. Profile Conductance.pH, and
Temperature. Determine
Stratification Status
3. Determine Secchi Disk
Transparency.
4 Prepare Blank (at First Lake
Only).
5. Collect Water Sample in
Van Dorn Sampler
-Withdraw DIG and pH Syringe
Samples
-Withdraw and Preserve
Nitrate/Sulfate Aliquot.
-Transfer Remaining Sample
to a 4-L Cubitainer.
6 If Necessary, Obtain a
Duplicate Sample.
7 If Necessary, Obtain a
Triplicate Sample.
8. Verify that Form and Labels are
Correctly Filled Out.
is shown in Figure 6-3. (Table 6-1 lists the data
forms and labels used in the field.) The observer
notes watershed characteristics (e.g., inlets, outlets,
dams, and local disturbances) that can be determined
from the air. The lake data form contains an outline of
the lake, sketched previously from U.S. Geological
Survey (USGS) or equivalent topographic maps. The
sampling location is marked on the sketch with an
"X." The pilot then lands at or near the deepest part
of the lake. This point is determined by using a
combination of visual observations from the air and
the electronic depth recorder.
When the helicopter crew arrives at the given
coordinates, the members may find conditions that
require special procedures. No sample is taken if
there is found to be: (1) no lake, (2) more than one
lake, (3) a stream or other flowing water, (4) a lake
too shallow (<0.75 m) to allow a debris-free water
sample to be obtained, (5) an inaccessible lake, (6) a
lake with high conductance (> 1500 nScm), (7) a
frozen lake, (8) an urban or industrial site, (9) a stock
pond (i.e., agricultural watering pond), or (10) no
permission for access. For a multilobed or dendritic
lake, the observer determines the location of the best
29
-------
Figure 6-3. National Surface Water Survey Form 1 - Lake Data.
National Surface Water Survey
Form 1 Lake Data
Helicopter
D Ground Team
D D M M M Y Y
Date ,—._. — ^_»_-^._-
Sampling Time .
Meter ID- l_l ,
State
Lake ID
Lake Name
Map Coordinates
Photographs^ )
Frame ID Azimuth
„.- Lap Card
Loran Readings ()
Lat ^_ *_, ^'^ u_..^J .
Long i__i i_i i_i*i__i • f • i
. —h
Initial *—^-~.
Final • *. -*
Initial ^-•.^4
Final _- —.
, i_, pH
Altimeter . ,,
i i—i i_i\_/
Disturbances Within 100 Meters of Shore
Q Roads D Livestock D Mines/Quarries D Fire
D Dwellings D Industry D Logging D Other
Secchi Depth Disappear , ..
Reappear
Site Depth u_))_t_lft Q|Site Depth (ft)xQ 3048 m/ft =i—»t—i m Q[ Air Temp-—' ^^°
Lake Stratification Data
Depth
T°C
Bottom-1 5m . .. v . (""")
AT°C(1 5, B-1 5m) ^-
.,. v .Q
~-~O
O
US
pH
-—Q
^"^ * * >^^
If A > 4°C Proceed
If Not, Stop Here
Site Depth T°C /jS
^,^^,0 - o _-~^_
AT°C(1 5, 06 Depth) _^^ Q I If AT >
Lake Diagram (from topographic map)
IN Inlets ( )
Rpsprvoir
Verified by
1
Site Depth
Check One T°C
D<20m D>20m
fi in . . ,_ -p .
8 1 R t_^ • — .
m 9n v.^.rt, rf
•] 2 ^Pi ,
14 30 ^. ^. .
16 1s -_ •-
18 1" ^.
20 45 • •• i- •
50 ~ ,
pH
O - . -Q
4°CFillln '
Data Block j
1
O
o
0
0
o
0
o
o
o
o
„
_~-^o
^^^-^-O
«^--O
u-^^-^,O
^^_^ ^o
^^k—^-w^O
o
_, o
^^--0
_, o
Comments D Not Sampled, See Below
Data Qualifiers
(A) Instrument Unstable
(n\ Redone, First Reading Not
^ Acceptable
(c) Instruments, Sampling Gear
Not Vertical in Water Column
(D) Slow Stabilization
©Cable Too Short
• Do Not Meet QCC
< Sample Collected at 0 5m
CYj(z)Other (explain m Comments section)
Reason Lake n Flowing Water D Inaccessible G No Access Permit D Urban/Industrial O Frozen
Field Lab Use Only
Time Received
Field Crew Date
[ Helicopter ID j Crew ID
Observer (Print)
Sampler (Print)
Obs Sign
Ground Crew Member
Form Distribution
White Copy — ORNL
Pink Copy— EMSL-LV
Yellow Copy— Field
Sign
30
-------
Table 6-1. Data Forms and Labels Used in the Field,
Western Lake Survey - Phase I
Data Form
Number
1
2
3
Description
Lake Data Form
Batch QC/Field Data Form
Shipping Form
Hydrolab Calibration Form
Location of
Facsimile
Figure 6-3
Figure 5-8
Figure 6-1 1
Sample Tracking and Custody Figure 6-8
Form
Field Sample Label Figure 6-5
Field Audit Sample Label Figure 6-10
Aliquot Label Figure 6-6
sampling site, following specific guidelines; for small
lakes, sampling procedures are modified.
The rotor wash of the helicopter can create a surficial
disturbance. The disturbance is normally away from
the sampling point and is minimized by the pilot's
positioning of the helicopter.
While the pilot maintains position by visual reference
to landmarks or an anchored buoy, as conditions
dictate, the sampler must perform the following
operations in the order given:
1. Measure the lake depth at the sampling site with
a calibrated sounding line, then record the result
on the lake data form.
2. Use the Hydrolab to profile the pH, conductance,
and temperature measured at 1.5 m below the
surface and at 1.5 m above the lake bottom. (In
shallow lakes, only one set of readings is taken,
at 0.75 m.) If the temperature difference exceeds
4°C, the sampler takes a third set of
measurements at 60 percent of the lake depth. If
the temperature difference between the top and
the 60 percent depth is <4°C, the lake is
classified as weakly stratified. If the temperature
difference exceeds 4°C, the lake is considered to
be strongly stratified. In a strongly stratified lake,
the sampler obtains a temperature and
conductance profile at 5-m intervals for lakes
greater than 20 m deep and at 2-m intervals for
lakes less than 20 m deep. Figure 6-4 shows
how the profile is taken and how the stratification
is determined. The sampler records the results on
the lake data form.
3. Measure the Secchi disk transparency by
lowering a Secchi disk secured on a calibrated
line into the water on the shady side of the
helicopter until the disk disappears from view,
then raising the disk until it reappears. The
observer records both of these depths on the lake
data form. Their average is the Secchi disk
transparency. If the Secchi disk is still visible
when it rests on the bottom of the lake, the
observer does not enter a reappearance depth on
the lake data form but makes an explanatory
notation in the comments section of the form. The
observer must not wear sunglasses unless they
have photogray prescription lenses. If sunglasses
are worn, the observer makes a notation of this in
the comments section of the form. In addition,
any conditions such as glare, choppy water, or
other physical interferences that are hindrances to
taking the reading are documented on the lake
data form.
4. Collect the sample from the upwind side of the
helicopter, where the potential for contamination
from engine exhaust is minimal. The sampler
rinses the 6.2-L Van Dorn sampling unit with
surface water, lowers the unit to 1.5 m below the
lake surface, triggers it to collect a sample, raises
it to the surface, then sets it on the pontoon
platform in a vertical position. This position
prevents the sample from leaking out and
prevents air from leaking in. It is imperative that
air is not introduced before step 5 is performed.
5. Take DIG and pH syringe samples from the
Luer-Lok syringe port on the Van Dorn sampling
unit. The sampler uses a 60-mL syringe
equipped with a valve to withdraw a 20-mL
aliquot, rinses the syringe with this aliquot and
discards the rinse, then withdraws a 60-mL
aliquot and seals the syringe. Repeating the
procedure, the sampler obtains a second syringe
sample. The sampler fills out field sample labels
(see Figure 6-5), excluding "Batch ID" and
"Sample ID" which are assigned at the field base,
and attaches the labels to the syringes. After
labeling the syringes, the sampler places them in
a plastic bag and stores them in the cooler
(maintained at 4°C).
6. Prepare the Cubitainer sample. The sampler
rinses a clean 4-L Cubitainer with three 500-
mL portions of sample, fills it with as much
sample as possible, compresses it to remove all
headspace, then caps it securely. The field
sample label is attached and completed. After it is
labeled, the Cubitainer is stored with the syringes
in the cooler.
7. Collect a duplicate sample. At the first lake
sampled each day, one helicopter crew from each
field base (as assigned by the field base
coordinator) collects a duplicate sample by
31
-------
Figure 6-4. Determination of temperature stratification class and lake temperature profile. Western Lake Survey - Phase I.
± Water Line
-^.~.-.-_-.-_-_-_-_-LJ-_-LJ-_- -_---_- .--..-_-_-_-_-_-_-.-,_n_r_j-
1 5 m
If A°T <4°C, lake is
not stratified (no
additional °T
measurements are
necessary)
If A°T >4°C, then °T
measured at 60%
of lake depth
If A°T <4°C, lake is
weakly stratified
(no additional °T
measurements are
necessary)
If A°T >4°C, lake is
strongly stratified
(additional incremental
°T measurements are
necessary)
(60% depth)
•Depth at Which °T
Measurement Taken
E E
& in
>• >-
0) 0>
> >
o> o>
0) 03
E E
d d.
0) 01
0) O
T3 T3
E E
o o
CM CM
A V
CD 0
-^ J*
CD CD
Deepest Spot
32
-------
Figure 6-5. Field sample label, Western Lake
Survey - Phase I.
Lake ID
Date Sampled
Crew ID
Time Sampled
Sample Type
(Check One)
Routine
Duplicate
Blank
Batch ID
Sample ID
repeating steps 4 through 6. On the label, sample
type "Duplicate" is checked.
8. Collect a field blank sample. Each helicopter crew
prepares one field blank at the first lake sampled
each day before collecting the routine sample. In
place of step 4, the sampler rinses the Van Dorn
sampling unit with three 200-mL portions of
deionized water, then fills it with deionized water.
Step 5 is omitted, and step 6 is performed as for
a lake sample. The sample type "Blank" is
checked on the label.
9. Collect and preserve the nitrate-sulfate aliquot
(the EMSL-LV split sample). Helicopter crews
collect nitrate/sulfate ahquots at calibration lakes
only.
The sampler must prepare one 125-mL aliquot
as follows:
• Complete and affix an aliquot label (see
Figure 6-6) to a 125-mL Nalgene bottle. Fill
the bottle to the shoulder with sample from
the Van Dorn.
• Using a dropper bottle, add 2 drops (0.1 ml_)
of a 5 percent solution of reagent-grade
mercuric chloride (HgCl2) to the aliquot bottle,
record the amount of preservative used on
the aliquot label, cap the aliquot bottle tightly,
and invert the bottle several times to mix the
contents.
• Tape the cap on with electrician's tape, and
place the bottle in a plastic bag in the cooler for
transport.
10. Upon completion of steps 1 through 9, rinse the
Hydrolab sonde and the Van Dorn sampler with
deionized water, and store them securely in the
helicopter. The observer verifies that the lake
data form is properly completed and that all
sample containers are correctly labeled.
11. The helicopter proceeds to the next lake, where
the same lake site activities are performed. When
time or weather conditions necessitate, the
helicopter returns to the field base. The helicopter
is refueled, when necessary, at remote airports or
by fuel truck. In some cases, where sampling
sites are more than 150 miles from the field base,
remote bases are established. The helicopter and
its crew remain at the remote base overnight, but
the samples are flown to the field base by fixed-
wing aircraft.
6.7.3 Field Base Activities Conducted at the End
of the Sampling Day
Upon the return of the helicopter crew to the field
base, the field samples are transferred to the
laboratory coordinator. The Hydrolab calibration is
checked at the end of each day. Any instrumental
drift is noted on the calibration form and on the lake
data form, and the affected data are qualified
appropriately. If a drift problem is significant and a
reliable Hydrolab is available, the faulty Hydrolab is
not used on the next sampling day. The
manufacturer's instructions for care and maintenance
of the pH meter and electrode are followed. The
rechargeable batteries are charged overnight, and the
electrodes are stored in tap water or 3M KCI.
All lake data forms are checked for consistency. After
supplies and equipment are checked and are stored
for the next sampling day, the helicopter crew, duty
officer, and field base coordinator participate in a
debriefing to discuss the day's activities and to
prepare for the next day's sampling activities.
6.2 Activities of the Ground Sampling
Crews
Each ground sampling crew is composed of two
samplers. Depending on the circumstances (i.e., lake
location and availability of pack animals), as many as
three logistics support personnel may aid in carrying
equipment to the lake. A local Forest Service expert
travels with the samplers to ensure that the proper
lake is located. Both samplers must be qualified to
33
-------
Figure 6-6. Aliquot label, Western Lake Survey - Phase I.
Aliquot
Batch ID
Sample ID
Date Sampled
Preservative
Amount
Parameters
Note. The aliquot
number, preservative,
and parameters are
preprinted on the
aliquot labels
operate all equipment and must follow prescribed
procedures. For each excursion, the activities are
divided into those conducted (1) at the field base (or
remote base) prior to sampling, (2) en route to or at
the lake site, and (3) after lake-site activities are
completed (see Figure 6-7).
6.2.7 Field Base Activities
Before leaving the field base (or remote base),
ground crews perform the following tasks:
• Check and calibrate the temperature meter
(see Section 7.2.1).
• Check and pack the equipment and supplies
necessary for the sampling excursion. Sample
containers are prepackaged into kits for each
lake. Sampling crews should obtain additional
kits as reserves and in case additional QA
samples (including field blanks) are required
for a given excursion.
• Coordinate the sampling plan with the field
manager, and file an appropriate sampling
itinerary. The itinerary includes the estimated
duration of the excursion, a check-in
schedule, and, when applicable, the location
of overnight stops and a time and location for
samples to be transferred for delivery to the
field laboratory.
6.2.2 Lake Site Activities
6.2.2.1 Verification of Lake Location-
The ground crew must verify the map coordinates of
the lake as follows:
• Compare the lake shape to that shown on the
map (USGS 7.5 minute topographic map or
equivalent).
• Determine the position of the lake relative to
identifiable topographic features shown on the
map.
• Determine the position of the lake by compass
triangulation on suitable landmarks.
• Use maps other than USGS topographic maps
(e.g., Forest Service maps) to confirm the lake
location.
• Obtain assistance from a local person (usually
from the Forest Service) who is familiar with the
area.
If the lake in question is confirmed as the proper lake
to be sampled, the ground crew completes the site
description portion of the data in the field logbook.
When exceptional conditions are found at the given
coordinates, the ground crew follows the same
procedures as the helicopter crews follow. These
procedures are listed in Section 6.1.2.
6.2.2.2 On-Shore Activities-
The ground crew must perform the following on-
shore activities prior to sampling:
• Collect and clean rocks (if available) for use as
an anchor.
• Inflate the boat, and load the equipment and
supplies.
34
-------
Figure 6-7. Flowchart of ground crew activities, Western Lake Survey - Phase I.
Activities Conducted
at Field Base
before Departure
1. Check Instruments.
2. Pack Equipment and Supplies
Activities Conducted
at Lake Site
before Boarding Boat
1. Verify Lake Identity.
2. Record Site Characteristics.
Activities Conducted
at Lake Site
on Boat
1 Select Sampling Site on Lake.
2. Determine Sampling Site Depth.
3. Determine Secchi Disk Transparency
4. Determine Stratification Status through
in situ Temperature Profile
5 Prepare Blank (at First Lake Only)
6. Collect Water Sample in Van Dorn
Sampler
-Withdraw DIG and pH Syringe Samples.
-Withdraw Nitrate/Sulfate Aliquot
-Transfer Remaining Sample to a
4-L Cubitainer.
7 If Necessary, Obtain a Duplicate Sample
No
Activities Conducted
after
Sampling Excursion
. Check Samples and Data Forms and
TransferThem to Transfer Personnel or to
Forest Service Field Manager at Field
Base.
. Discuss Day's Sampling Excursion Plan
and Prepare for Next Day's Sampling.
Activities Conducted
at Lake Site
on Shore
1. Transfer Data Entered in Logbook During
Lake Site Activities to Lake Data Form
2. Determine pH (Use Indicator Strips)
3. Preserve Nitrate/Sulfate Aliquot
4. Pack Samples for Transport.
5. Verify that Form and Labels are Correctly
Filled Out.
Complete field sample and nitrate sulfate aliquot
labels (except for "Batch ID" and "Sample ID")
for all samples to be collected.
Record site description information on the lake
data form provided in the field logbook.
Check the operation of the temperature meter
according to the directions in the operations
manual for the instrument.
Check the calibration of the temperature meter
and thermistor as described in Section 7.2.1.
35
-------
6.2.2.3 On-Lake Activities--
On the lake, the ground crew locates the part of the
lake that is estimated to be the deepest and, if
weather conditions require, anchors the boat. The
crew then must perform the following operations:
1. Measure the depth at the sampling site. Use a
weighted calibrated sounding line, and record the
result on the lake data form in the field logbook.
2. Profile the temperature at 1.5 m below the lake
surface and at 1.5 m above the bottom by
lowering the thermistor probe to the proper depth,
allowing the reading to stabilize, and recording the
temperature on the data form in the field logbook.
In shallow lakes (less than 3 m deep), the
temperature is measured at 0.75 m below the
surface.
If the temperature difference between the two
depths exceeds 4°C, the crew takes a third
measurement at 60 percent of the lake depth If
the temperature difference between the top and
the 60-percent depth is less than 4°C, the lake
is classified as weakly stratified. If the
temperature difference exceeds 4°C, the lake is
considered to be strongly stratified. In a strongly
stratified lake, a temperature profile is obtained at
5-m intervals for lakes greater than 20 m deep
and at 2-m intervals for lakes less than 20 m
deep (see Figure 6-3).
3. Measure the Secchi disk transparency of the
water on the shady side of the boat. The
samplers in boats use the same procedure for
this measurement as the samplers in helicopters
do; the procedure is described in Section 6.1.2,
step 3.
4. Collect samples of the same types as helicopter
crews collect (see Section 6.1.2, step 4). The
ground crews, however, collect a nitrate sulfate
aliquot for every routine, duplicate, and blank
sample they collect. Also, a crew member fills a
10-mL vial with lake water from the Van Dorn
sampler for pH determination on shore.
6.2.2.4 On-Shore Activities After Sample
Collection-
On shore, following sample collection, the ground
crew performs the following activities:
1. Measure the pH of the samples. Because neither
pH meters nor Hydrolabs are available to the
ground crew, a crew member makes on-site pH
determinations with ColorpHast pH indicator strips
that cover two pH ranges (4.0 to 7.0 and 6.5 to
10.0). The crew member places a pH indicator
strip in the vial, allows the color to develop for 10
minutes, compares the color of the strip to the
color chart, and records the pH value on the lake
data form in the field logbook.
2. Preserve the nitrate-sulfate aliquot (split) by
adding two drops (0.1 ml) of a 5 percent solution
of reagent-grade HgCl2; then tape the cap on
the aliquot bottle with electrician's tape.
3. Pack the Cubitainers, syringes, and split samples
in coolers with frozen gel packs and
thermometers for transporting to the field
laboratory.
4. Transcribe all field logbook data onto the lake
data form. The member of the crew who does not
transcribe the data checks the form for
transcription errors.
5. Initiate a sample tracking and custody form (see
Figure 6-8).
6.2.3 Activities Following Completion of Lake
Site Activities
6.2.3.1 Delivery of Samples and Data Forms to
the Field Laboratory--
If a ground crew returns to the field base after a
sampling excursion, the crew members report to the
field manager upon arrival.
• The crew transfers custody of the samples and
the data forms to the field manager, who
records the time of receipt and signs the
custody form.
• The field manager conveys custody of forms
and samples to the laboratory coordinator, who
measures the temperature of each cooler and
records the results on the custody form and on
the appropriate lake data form. The laboratory
coordinator also records the date and time of
receipt of each sample on the corresponding
lake data form.
NOTE: The custody form must be signed by the
field manager or the field manager's
designee before the field laboratory will
accept samples. The field base
coordinator must also be informed of
sample arrivals and of the total number
of samples received.
If the ground crews do not return to the field base,
they are met at a pick-up point by a transfer crew.
• A member of the ground sampling crew
measures the temperature of each 30-qt ice
chest (or portable cooler) with a field
36
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Figure 6-8. National Surface Water Survey Sample Tracking and Custody Form.
National Surface Water Survey
Western Lake Survey
Sample Tracking And Custody Form
Base Site: _
Crew ID:
Date Out: __
Date Returned:
Number of Containers
Lake ID
4-L
Cubitainer
Syringes
Nitrate/Sulfate
Aliquot
Conpleted
Lake Data
Form
Comments
1 Relinquished by
(Sampler)
3. Received by.
(Field Manager)
Date
Time
Temps
2. Received by:
(Pick-up Crew)
4 Received by
(Lab Coordinator)
Date
Time
Temps
Comments.
Copies: Base Coordinator, Field Manager, Field Lab, EMSL-LV (Comm. Ctr.)
thermometer and records the temperature on
the custody form. The field thermometer is
placed in a corner of the cooler or is taped to an
inner wall so that the temperature of the cooler,
not of a gel pack or sample, is measured.
The Cubitamers, syringes, and splits are
transferred to ice chests or Styrofoam coolers
containing new frozen gel packs.
The samplers give the lake data forms and
custody forms to the transfer crew.
The transfer crew conveys any necessary
supplies or information to the ground sampling
crew and obtains information and supply
requests from the sampling crew for the field
manager.
37
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6.3 Field Base Operations
The field base includes a fully equipped mobile
laboratory that is staffed by a field laboratory
coordinator, a field laboratory supervisor, and three
analysts. The field laboratory coordinator is
responsible for the overall operation of the laboratory
(sample tracking and logistics, data, forms, safety,
etc.)- The field laboratory supervisor and the analysts
are responsible for sample measurements made at
the field base and for sample processing. If
necessary, the field laboratory coordinator also
assists with sample processing. This section
describes the field base activities that are outlined in
Figure 6-9. Section 6.3.1 refers to reagent
preparation, and Section 6.3.2 describes sample
processing.
6.3.1 Reagent Preparation
Reagents for aluminum extraction, DIG determination,
and pH determination must be prepared before
helicopter crews return with samples. Reagents used
for lake-site measurements must be made as
required. Detailed procedures for reagent
preparations are given in Morris et at. (1985).
6.3.2 Sample Processing
The following steps describe sample processing
operations. These operations fit into the sample flow
as shown in Figure 6-1. They are performed in the
order given.
6.3.2.1 Sample Description and Identification-
Samples are organized into batches that are
processed together. A batch consists of all samples
(approximately 20 to 30, including routine, duplicate,
blank, split, and audit samples) that are processed at
a field base on a given day. Each batch is assigned a
unique batch ID number, which is recorded on the
labels of all samples and of corresponding aliquots.
Each sample is then randomly assigned a sample ID
number as follows:
• Routine Samples - Three sample containers
are filled at each lake, namely two 60-mL
syringes (for DIG and pH determinations) and a
4-L Cubitainer. One sample ID number is
assigned to all three containers and is recorded
on each container label.
• Duplicate, Triplicate, and Blank Samples -
Sample ID numbers are assigned in the same
manner as for the routine samples. There are no
syringe samples for the blanks.
• Field Audit Samples - One or two 2-L field
audit samples (received each day from a central
source) are included in each day's batch of
samples. The label for the field audit container is
shown in Figure 6-10. Two syringes are
labeled, filled, and sealed for pH and DIG
determinations. The code (Table 6-2) indicates
what kind of a sample it is and the concentrate
lot number. A field audit sample is assigned a
sample ID number in the same manner as a
routine sample. The sample ID number is
recorded on the label.
After the batch and sample ID numbers are assigned
and are recorded on each sample label, the same
information is entered on the batch/QC form. Also,
the lake ID and the appropriate code for each sample
(from Table 6-2) are entered on the batch/QC form.
The sample ID numbers are assigned at random to all
samples in a batch, except for certain calibration lake
samples (see Section 5.2). Furthermore, sample ID
numbers run consecutively from 1 to the number of
samples in the batch. Audit samples must not always
be assigned the same sample ID number.
NOTE 1: Field audit samples are processed
exactly like routine lake samples.
NOTE 2: Seven different aliquots (numbered as
in Table 6-3) are prepared from
each field sample (routine, duplicate,
audit, and blank samples). Each
aliquot is assigned the same batch
and sample ID numbers as the
sample from which it is prepared.
(This is not always the case for all
calibration lake samples: see Section
5.2). Additional aliquots are taken for
split samples.
6.3.2.2 DIG Determination-
Immediately after assignment of batch and sample ID
numbers, the laboratory supervisor begins the DIG
analyses. DIG is determined in routine, lake duplicate,
and field audit samples. The routine and lake
duplicate samples are contained in sealed syringes
(filled at the lake site) and are kept in refrigerators in
the field laboratory at 4°C until analysis. For field
audit samples, a syringe sample is taken from the
refrigerated 2-L sample prior to analysis. The results
are recorded on the batch/QC form. The
measurement procedures are discussed in Section
7.2.1 of Drouse et al. (1986). Copies of all raw data
are kept in a DIG logbook and must be sent to the QA
manager when requested.
6.3.2.3 Sample Filtration, Preservation, and
Aliquot Preparation-
The aliquot bottles are pre-labeled and pre-
numbered before filtration and aliquot preparation
begin. One analyst filters the samples in a laminar-
flow hood referred to as the "clean air station"; a
38
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Figure 6-9. Flowchart of daily field base activities, Western Lake Survey - Phase I
Before
Sample Arrival
1. Prepare reagents for analysis:
a) Total extractable Al
b)DIC
c)pH
2. Warm up and calibrate instruments.
a) Turbidimeter
b) Carbon analyzer
c) pH meter
4 Sample Arrival
1 Confirm with sampling crews delivery
of samples and forms
1 Insert required audit samples, assign batch
and sample ID numbers, start batch form
2 Measure DIG
3. Mnasuro pH
4. Measure turbidity
5. Measure true color
6. Complete batch and shipping forms
Shipment
of Supplies
and Forms
Figure 6-10. Field audit sample label, Western Lake Survey - Phase I.
Field Audit Sample
Radian ID No
Date
Shipped
Code
Batch
Date
Received
ID
39
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Table 6-2. Sample Codes Used to Complete Lake Data Forms,
Western Lake Survey - Phase I
Sample Type
Normala
Code
RH
RG
OH
DG
BH
BG
TB
TD
Description
Routine lake sample - helicopter
Routine lake sample - ground
Duplicate lake sample - helicopter
Duplicate lake sample - ground
Field blank - helicopter
Field blank - ground
Field laboratory (trailer) blank
Field laboratory (trailer) duplicate
Calibration Study3 RHCt>
Audit
THCb
RGC
DGC
F L
Split
Routine calibration - helicopter
Duplicate calibration - helicopter
Triplicate calibration - helicopter
Routine calibration - ground
Duplicate calibration - ground
• Radian ID number
• Concentrate (or lake) lot number
• Natural or synthetic (concentration level)
N = natural L = low synthetic
• Type of audit sample
F = field (no other type used)
• Shipping destination of split sample
E = ERL-C
L = EMSL-LV
A split sample is an additional aliquot from a routine,
duplicate, audit, or blank sample, and has the same ID
number as the original sample. However, the aliquot has
an additional sample code. For example, if the original
sample is assigned the ID number 4, the split sample also
receives the ID number 4, with the letter E (or L) recorded
in the Split Code column on the batch/QC form.
a Samples require a lake ID, except for TB
b This sample can have a "W" as a fourth character, indicating that it was withheld as part of the
calibration study
second analyst prepares aliquots and split samples
and preserves them if necessary. Both analysts wear
disposable gloves while performing these tasks. The
seven aliquots prepared from each sample are
specified in Table 6-3.
There are two types of split samples for WLS-I.
Descriptions of both are given below and are
summarized in Table 6-4. When a sample is split,
the appropriate split code is recorded on the
batch/QC form.
• ERL-C (Corvallis) Split - An ERL-C split
consists of one aliquot that is prepared in the
same way as aliquot 1 (Table 6-3), except that
the sample volume is 125 mL and a 125-mL
container is used. If the volume permits, all
samples are split for shipment to Corvallis.
When volume limitations exist, routine aliquots
and analyses take precedence. At ERL-C, the
samples are analyzed by inductively coupled
plasma atomic emission spectroscopy (ICP),
which provides checks on the performance of
the analytical laboratories as well as additional
data that are potentially useful in understanding
lake chemistry. This split (annotated by an "E"
on the batch/QC form) is shipped to the
Corvallis laboratory on a multiple-batch basis
(e.g., weekly). This split sample need not be
stored at 4°C.
EMSL-LV Split - An EMSL-LV split consists
of one 125-mL aliquot that is collected and
preserved as described in Sections 6.1.2,
6.2.2.3, and 6.2.2.4. At Las Vegas, the split
samples are analyzed by ion chromatography for
NOs" and SO42'. The purpose of analyzing
this split sample is to compare preservation
methods, to compare the effects of different
holding times before preservation, and to
provide an additional check on sampling,
processing, and analytical performance. Split
samples (indicated by an "L" on the batch/ QC
40
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Table 6-3. Aliquots, Containers, Preservatives, and Corresponding
Analyses, Western Lake Survey - Phase I
Aliquot
(Container Volume)
Preservative and
Description
Analyses
1
(250 mL)
2
(10 mL)
3
(250 mL)
4
(125 mL)
5^
(500 mL)
6
(125 mL)
7
(125 mL)
Filtered, preserved with
HNO3 to pH < 2
Filtered, preserved with
MIBK-HQ extract
Filtered, no preservative
Filtered, preserved with
H2S04 to pH < 2
Unfiltered, no preservative
Unfiltered, preserved with
H2SO4 to pH < 2
Unfiltered, preserved with
HNO3 to pH < 2
Ca, Mg, K, Na,
Mn, Fe
Extractable Al
CI-, total dissolved
F-, S042-, N03-,
Si02
DOC, NH4*
pH, BNC, ANC,
conductance, DIC
Total P
Total Al
a There must be no headspace in the Aliquot 5 bottle.
b Aliquots 2, 3, 4, 5, and 6 must be stored at 4°C in the dark
Table 6-4. Split Sample Descriptions, Western Lake Survey - Phase I
Split Quantity Number Description
ERL-C
125 mL
EMSL-LV 125 mL
All samples3
All samples collected
by ground crews, all
calibration lake samples
collected by helicopter
crews, and all natural
audit samples.
Filtered sample acidified with
HNO3 to pH <2
Unfiltered sample preserved in
field with 0.1 mL 5% HgCI2
a Except when there is insufficient sample as a result of other splits
form) are stored in the dark at 4°C and are
shipped to Las Vegas on a daily basis.
6.3.2.4 Extractable Aluminum-
The WLS-I procedure for processing the sample for
extractable aluminum is identical to the procedure
used during ELS-I. The third analyst begins this
procedure when the DIC measurements are begun.
The aluminum in the sample is extracted into MIBK,
which is transferred to a 10-mL centrifuge tube that
is capped tightly. An aliquot label is attached. This is
aliquot 2 in Table 6-3. The aliquot is stored at 4°C
in the dark until shipment.
6.3.2.5 pH (Field Laboratory)--
The WLS-I procedure for field laboratory pH
determination is identical to the procedure used
during ELS-I. After determining DIC, the laboratory
supervisor determines the pH of the sample in the
second syringe, which has been allowed to come to
room temperature. The QC procedures are discussed
in the ELS-I QA plan (Drouse et al., 1986, Section
7.2.2).
6.3.2.6 Turbidity--
The WLS-I procedure for turbidity determination is
identical to the procedure used during ELS-I. The
41
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analyst who prepares the aliquots also measures the
turbidity of raw portions of the routine, duplicate, and
blank samples. A Monitek Model 21 laboratory
nephelometer is used for this procedure. The
nephelometer is calibrated directly in nephelometnc
turbidity units (NTUs). The QC procedures are
discussed in the ELS-I QA plan (Drouse et al., 1986,
Section 7.2.3).
6.3.2.7 True Color--
The WLS-I procedure for true color determination is
identical to the procedure used during ELS-I. The
same analyst who performs the turbidity analysis
centrifuges raw portions of routine and duplicate
samples (as well as audit and blank samples when
sample volume permits) and measures the color of
the supernatants with the Hach Model CO-1 Color
Test Kit, following the manufacturer's instructions.
The QC procedures are described in the ELS-I QA
plan (Drouse et al., 1986, Section 7.2.4).
6.4 Training
The WLS-I procedure for training helicopter
sampling and field laboratory personnel is identical to
the procedure used during ELS-I. Ground sampling
creates new safety and technical considerations, so
additional training is provided for ground sampling
participants. This training is carried out at Las Vegas
and at the field bases and remote sites. Further
discussion of training activities can be found in Morris
et al. (1985).
6.3.2.8 Sample Shipment-
When a batch is completely processed and is ready
for shipment, the samples are assembled into groups
according to their shipping destinations. Except for
ERL-C splits, all samples are stored at 4°C until
they leave the field laboratory. Split samples are
shipped to ERL-C and to EMSL-LV. All other
samples are shipped to an analytical laboratory (see
variations in sample shipment protocol for calibration
lake samples in Section 5.2). Before shipping, the cap
of each aliquot bottle is taped on, and the bottle is
sealed in a plastic bag that is placed in a Styrofoam-
Imed shipping carton, along with 8 to 12 frozen
freeze-gel packs to maintain the aliquots at 4°C.
(Approximately eight samples will fit in one shipping
carton.) One multicopy set of Form 3 - Shipping
(see Figure 6-11) is completed for each carton, and
two copies (sealed in a plastic bag) are enclosed in
the carton. The carton then is sealed and is shipped
by overnight delivery to its destination.
Upon receiving the shipment, the analytical laboratory
checks the temperature inside the shipping carton
and checks the condition of the shipping carton and
the aliquot bottles. The analytical laboratory also
verifies that all the aliquot bottles listed on the
shipping form are included in the shipment. If there is
any discrepancy, the field laboratory coordinator
should be notified immediately, and the deviations
should be noted in a cover letter to the QA manager.
6.3.2.9 Data Distribution-
The WLS-I procedure for distribution of field data
forms is identical to the procedure used during ELS-
I. A flowchart of the process is included on page 28
(Figure 6-1).
42
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Figure 6-11 National Surface Water Survey Form 3 - Shipping.
National Surface Water Survey
Sample Management Office
P.O. Box 818
Alexandria, VA 22314
NSWS
Form 3
Shipping
Received by
If Incomplete Immediately Notify
Sample Management Office
(703) 567-2490
Page
of
From
(Station ID)
Sample
ID
01
02
03
04
05
06
07
08
09
10
1 1
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
To
(lab)
Batch
ID
Date Processed
Aliquots Shipped
(For Station Use Only)
1
2
3
4
5
6
7
8
Splits
Date Shipped Date Received
Air-Bill No.
Sample Condition Upon Lab Receipt
(For Lab Use Only)
Qualifiers
X Aliquot Shipped
M Aliquot Missing Due to Destroyed Sample
While - Field Copy Pink - Lob Copy Yellow - SMO Copy Gold - Lab Copy tor Return to SMO
43
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7.0 Field Measurement Quality Control Checks
Field measurements are those made by the helicopter
sampling crews, the ground sampling crews, and the
field laboratory crews. The QC checks associated
with these measurements are described in Sections
7.1, 7.2, and 7.3, respectively.
7.1 Quality Control Checks for
Measurements Taken by Helicopter
Crews
The lake site measurements taken by helicopter
crews consist of three Hydrolab determinations
(lake-water temperature, pH, and conductance),
Secchi disk transparency, air temperature, and site
depth. All measurements are recorded on the lake
data form.
7.1.1 Hydrolab
The Hydrolab instrument is used to measure in situ
lake-water temperature, pH, and conductance.
The QC procedures consist of calibrating the
instrument at a designated clean work station at the
base (or remote) site before and after each daily
sampling excursion. Any instrumental drift between
calibrations is monitored. These procedures are
adapted from Hydrolab (1985). The following is a
summary of QC procedures for the Hydrolab.
• Lake-water temperature - There is no
calibration control for temperature. The
instrument is calibrated at the factory and should
be accurate to 0.2°C. The accuracy is checked
each day against a National Bureau of
Standards (NBS)-traceable thermometer, and,
if an error of 1°C or more is found, the
manufacturer should be consulted and the
discrepancy should be recorded on the lake data
form. An error of this size usually indicates a
malfunction of the instrument. If a reserve
Hydrolab is available that meets specifications,
the faulty Hydrolab is replaced.
• pH - Following the daily calibration with
commercial standard buffer solutions, a QC
check sample (QCCS) of CO2-saturated
deionized water is measured. The QCCS has a
theoretical pH value of 3.91 at standard
temperature and pressure. The instrument drift
is determined by remeasunng the QCCS after
completion of all sample analyses. If either
QCCS reading deviates from the theoretical pH
by more than ±0.15 pH unit, the data tag
qualifier "Q" (Table 12-1) is recorded on the
lake data form.
• Conductance - A KCI standard of 147
uS/cm is used to calibrate the conductance
function. The same QCCS used to check the
pH function of the Hydrolab is used to check
the conductance function. The allowed error
on the QCCS, which has a standard specific
conductance value of 50 pS/cm, is ±20
uS/cm. This error is 1 percent of the highest
reading on the conductance meter scale used
(2,000 uS/cm).
7.7.2 Secchi Disk Transparency
There are no applicable QC checks for this
measurement.
7.7.3 Air Temperature
Ambient air temperature is measured by an outdoor
thermometer affixed to the outside of the helicopter.
The temperature is recorded on the lake data form.
There are no applicable QC checks for this
measurement.
7.7.4 Srte Depth
Ideally, the sampling site should be the deepest part
of the lake. This point is located with an electronic
depth recorder that is mounted to the helicopter.
Once daily, at the first lake to be sampled, the depth
recorder is checked against a calibrated sounding
line. The depth, which is measured in feet, is
recorded on the lake data form, where it is converted
to meters by multiplying the measurement in feet by
0.3048.
7.7.5 Elevation
Site elevation is taken from the map reading. This
elevation is confirmed by the helicopter altimeter,
which is periodically checked by the pilot. The map
contour reading and the altimeter reading are
recorded on the lake data form.
45
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7.1.6 Lake Location
The lake location is determined from map coordinates
(i.e., latitude and longitude) and is confirmed by the
loran-C instrument readout and by a comparison of
observed and map topographic features. The map
coordinates and loran-C readings are recorded on
the lake data form.
7.2 Quality Control Checks for
Measurements Taken by Ground
Crews
Ground crew samplers measure lake-water
temperature, pH, Secchi disk transparency, air
temperature, and site depth. The ground crew does
not use a Hydrolab. All measurements are recorded
on the lake data form.
7.2.7 Lake-Water Temperature
A temperature meter is calibrated before the first
sampling excursion of the day by measuring the
temperature of an ice slurry (4°C) and a water
sample (15 to 20°C) with the thermistor and with an
NBS-traceable thermometer. If the thermistor
readings differ from the thermometer readings by
0.5°C or more, the problem with the meter must be
identified and resolved by following the
manufacturer's instructions. A calibration check at the
lake site is done by comparing the reading of the
thermistor with that of a field thermometer in a
sample of lake surface water collected in a plastic
beaker. If the two readings differ by 2°C or more, the
in situ readings are qualified on the lake data form.
7.2.2 pH
No QC checks are available for pH determinations
that are made with pH indicator strips.
7.2.3 Secchi Disk Transparency
There are no applicable QC checks for this
measurement.
7.2.4 Air Temperature
Ambient air temperature is measured by reading an
NBS-traceable thermometer above the ground in the
shade. There are no applicable QC checks for this
measurement.
7.2.5 Site Depth
The samplers locate the sampling site by observing
shoreline topography and by performing a visual
inspection of the site while they are on the lake
surface. A calibrated, weighted sounding line is used
to determine sampling site depth in feet. The
measurement is recorded on the lake data form,
where it is converted to meters by multiplying by a
conversion factor of 0.3048. Ideally, the sampling site
should be the deepest part of the lake.
7.2.6 Elevation
Site elevation is taken from the map reading and is
recorded on the lake data form. There are no
applicable QC checks for this measurement.
7.2.7 Verification of Lake Location
The map coordinates of the lake are verified as
described in Section 6.2.2.1.
7.3 Field Laboratory Measurements
See the ELS-I QA plan (Drouse et al., 1986, Section
7.2) for QC checks for DIG, pH, turbidity, and true
color determinations.
46
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8.0 Analytical Procedures
WLS-I analytical procedures are identical to those These procedures, listed in Table 4-1, are described
used for ELS-I. The Las Vegas laboratory uses the fully in the ELS-I methods manual (Hillman et al.,
same procedures for sulfate and nitrate analysis of 1986) and are summarized in the WLS-I methods
the EMSL-LV splits as the analytical laboratory does manual (Kerfoot and Faber, 1987).
for analysis of the conventional nitrate, sulfate aliquot.
47
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9.0 Analytical Internal Quality Control
Analytical internal QC provisions for WLS-I are
identical to those for ELS-I. They are discussed fully
in Section 9.0 of the ELS-I QA plan (Drouse et al.
1986) and are summarized in Table 9-1.
Table 9-1. Summary of Internal Quality Control Checks for Analytical Methods, Western Lake Survey -Phase I
Parameter
QC Check
Control Limits
Corrective Action3
ANC, BNC, pH 1.
2
3.
4
5
6
Ions (CI", total dissolved F", la.
NH4f. NO3", SO42'
Titrant Standardization
cross-check
Electrode calibration
(Nernstian response
check)
pH QCCS (pH 4 and 10)
analysis
Blank analysis (salt spike)
Duplicate analysis
Protolyte comparison
Initial QCCS analysis
(calibration and
verification)
1.
2.
3.
4.
5
6
la,
Relative differences < 5%
Slope = 1.00 ±0.05
pH 4 = 4.00 ±005
pH 10 = 10 00 ± 0.05
[Blank] < 1 0 ueq/L (ANC
and BNC)
RSD <10% (ANC and
BNC) + 0 05 pH unit
(pH)
See Hillman et al (1986)
,b The lesser of the 99% CI
or value given in
Table 9-2 of Drouse et
1
2
3
4
5.
6
la.
Restandardized titrants.
Recalibrate or replace
electrode.
Recalibrate electrode.
Prepare fresh KCI spike
solution.
Refine analytical
technique,
analyze another
duplicate
See Hillman et al. (1986).
Prepare new standards
and
recalibrate
Metals (total Al. extractable
Al, Ca, Fe, K, Mg, Mn,
Na)
SiO2, total P, DIG, DOC,
Conductance
ib. Continuing QCCS anal-
ysis (every 10 samples)
2a Detection limit determi-
nation (weekly)
2b. DL QCCS analysis (daily,
metals and total P only)
al (1986)
2a Detection limits given in
Table 4-1
2b % Recovery = 100 ±
20%
!b Recalibrate Reanalyze
associated samples.
2a,b.Optimize instrumentation
and technique.
3 Blank analysis
4 Duplicate analysis
Ions, (CI", total dissolved F", 5 Matrix spike (except ext.
NH/, NO3", SO42~) Al,
DIC, and conductance
Metals (total Al, extractable 6 Resolution test (CI",
Al, Ca, Fe, K, Mg, Mn, NO3 ,
Na) SO4 only)
SiO2, total P, DIC, DOC,
conductance
3a. Blank < 2 x DL (except 3a,b. Determine and eliminate
conductance)
3b. Blank < 0 9 nS/cm
(conductance only)
4. Duplicate precision 4.
(%RSD)
limits given in Table 4-1
5. % Recovery = 100 ± 5.
1 5%
6 Resolution >60% 6
contamination source
Prepare fresh blank
solution Reanalyze
associated samples
Investigate and eliminate
source of imprecision.
Analyze another
duplicate
Analyze 2 additional
spikes.
If one or both outside
control limits, analyze all
samples in that batch by
method of standard
additions.
clean or replace 1C
separator column.
Recalibrate.
a To be followed when QC check is outside control limits.
49
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70.0 Performance and System Audits
10.1 Performance Audit Samples
Field audit samples are used as part of the QA
activities of WLS-I. The purpose of field audit
samples is to identify problems affecting data quality
that may occur during sample processing, shipment,
or analysis. These problems could include sample
contamination, sample degradation, solvent
evaporation, and improper or inaccurate sample
analysis.
The audit samples are shipped to the analytical
laboratories from the field bases as though the audit
samples were ahquots of routine lake samples. Every
attempt is made to ensure that the analytical
laboratory does not recognize the audit samples as
different from the routine lake samples. As a result,
the audit samples are double blind to the analytical
laboratory.
There are two types of field audit samples: field
synthetic audit samples and field natural audit
samples.
70.7.7 Field Synthetic Audit Samples
The field synthetic audit samples are prepared at a
central laboratory and are sent to the field laboratory
to be processed through all the filtration and
preservation steps and to be labeled as though they
were authentic lake samples. Thus, they are single-
blind samples to the field laboratory and,
concurrently, double-blind samples to the analytical
laboratory.
The desired composition of the field synthetic audit
samples is shown in Table 10-1 and reflects the low
concentrations of analytes expected in actual WLS-I
lake samples. Synthetic lots are prepared in bulk as
stock solutions. The stock solution is diluted to the
desired concentration and the dilute sample is
shipped to the field laboratories one day before
aliquot processing is scheduled.
70.7.2 Field Natural Audit Samples
Waters collected from Big Moose Lake in the
Adirondack Mountains, from Lake Superior at Duluth,
Minnesota, and from Bagley Lake in the Cascade
Range of Washington State are used as natural audit
samples for the survey. The waters of Big Moose
Lake are acidic; the Lake Superior waters represent a
buffered system; and Bagley Lake represents a
partially buffered system. In bulk, these natural
samples are passed in 50- to 200-L increments
through a 0.45-u-m filter into 2-L bottles and are
maintained at 4°C to minimize changes in
composition. These 2-L quantities are the individual
natural audit samples that are included in the sample
batches.
70.7.3 Application of Field Audit Sample Data
Data are obtained from the analyses of the field audit
samples for the following purposes:
• to judge the performance of the field bases in
the processing and shipment of samples
• to judge the continued capability of the analytical
laboratories to analyze the samples properly
• to establish a statistically valid estimate of the
overall bias and precision of the analyses
• to establish a statistically valid estimate of the
stability of a typical lake sample when stored at
4°C by evaluating the natural lake sample over
the period of the study.
Acceptance windows are established for the
measurement of each parameter in the audit samples.
A preliminary determination of the size of the windows
is based upon the information available for each
analytical method at the time the study is initiated; the
final determination is made after data verification is
completed. If the analytical results for a measurement
fall outside the acceptance window, the EMSL-LV
QA staff reviews the data to determine the cause of
the problem and immediately calls the analytical
laboratory or field base, whichever is appropriate, to
seek corrective action. Data for routine samples
analyzed with the audit samples also are checked to
determine if they were affected by the problem. If
they were affected, reanalysis of the samples in
question may be requested. The establishment of the
acceptance windows is summarized in Section 11 of
this QA plan and is described in more detail in Drouse
et al. (1986, Section 11).
Approximately 75 synthetic audit samples and 150
natural-water audit samples are scheduled to be
51
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Table 10. 1. Desired Composition of Field Synthetic Audit
Samples, Western Lake Survey - Phase I
Parameter
Concentration
Units
Acid-Neutralizing Capacity (AIMC)a
Al (total and extractable)
Base-Neutralizing Capacity (BNC)a
Ca
cr
Conductance^
DIC*
DOC
F", total dissolved
Fe
K
Mg
Mn
Na
NH/
NCV
P, total
pHa
Si02
S042-
10-50
001-0.10
10-50
0.1-1
0.1-1
1-50
0.1-1 0
0.1-1 0
0 01-0.05
0.02-1 0
0 1-1
0.1-1
002-1 0
0 5-3
001-0 50
001-050
0 005-0 03
4-5
1-5
1-5
lieq/L
mg/L
neq/L
mg/L
mg/L
uS/cm
rng/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
PH
mg/L
mg/L
a These parameters are related, and they affect the analytical results of
one another
b To be determined by concentration of other parameters.
Note Mass balance (anions versus cations) in the composition of field
synthetic audit samples must be maintained Nitrogen/phosphorus
ratio must be reasonable (10/20).
processed during WLS-I. A statistical evaluation of
the audit data, including the setting of audit windows,
should provide a good estimate of the bias and
precision of the analytical methods for each required
measurement. Furthermore, any change over time in
analytical results for the natural-water audit samples
without a corresponding change in results for the
other audit samples can be attributed to lack of
analyte stability. The findings of a comparative study
between audit sample types will provide an estimate
of the true maximum holding times allowable for each
type of analyte.
10.2 Quality Assurance System Audits
(On-Site Evaluations)
The system audits consist of qualitative evaluation of
field and analytical laboratory facilities, equipment,
and operations such as record keeping, data
reporting, and QC procedures.
70.2.7 Field Operations On-Site Evaluation
Each field base and helicopter sampling crew can
expect at least one on-site evaluation during the
course of the sampling effort. The purpose of the
on-site inspection is to review the sampling
procedures, field base operations, and QA efforts; in
addition, as many of the 60 ground sampling crews
as possible will be evaluated in the field. The on-site
evaluation for each field base and its corresponding
sampling crews should be conducted as soon as
possible after the start of operations. The
questionnaire in Appendix A of this document is used
to assist in the evaluation of ground sampling crews.
The questionnaire given in Appendix C of Drouse et
52
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al. (1986) is used for the evaluation of field base and
helicopter crews.
The field auditor conducts an in-depth review of all
field operations. This includes, but is not limited to,
(1) interviewing the field base coordinator, the Forest
Service field manager, and the field laboratory
supervisor; (2) observing the field base operations
(including field laboratory operations); (3) interviewing
sampling crews; (4) accompanying one or more of
the sampling crews during a sampling excursion; and
(5) writing a summary report that includes results.
observations, and recommendations. If there are any
problems, the evaluator must either have the
individuals involved correct them or must bring them
to the attention of the field base coordinator for
resolution.
70.2.2 Analytical Laboratory On-Site Evaluation
Each analytical laboratory participating in WLS-I can
expect a minimum of two m-depth, on-site
evaluations conducted by the EPA QA manager or his
authorized representative. The questionnaire in
Appendix D of Drouse et al. (1986) is used to assist
in the on-site laboratory evaluation.
The first on-site laboratory evaluation is performed
after the laboratory has successfully analyzed a set of
preaward Performance Evaluation (PE) samples for
the contract-required analyses and before the actual
survey analytical work begins. The PE samples
contain up to the maximum number of analytes for
which measurement is required, in the expected
concentration ranges. The PE sample results are
scored using the ELS-I Preaward Score Sheet given
in Appendix E of Drouse et al. (1986). Grading
emphasizes analytical accuracy, but a substantial
portion of the grade depends on meeting the QA,
internal QC, reporting, and deliverable requirements.
The auditor summarizes all observations in an on-
site laboratory evaluation report and brings all
problems to the attention of the laboratory manager
for corrective action.
The second on-site laboratory evaluation is
conducted after approximately one-third of the
WLS-I analyses have been completed. During the
second on-site evaluation, QA sample (audit,
duplicate, and blank) data and QC data received to
date are reviewed. The laboratory questionnaire is
updated, if necessary, and all changes since the first
on-site evaluation are noted. An on-site laboratory
evaluation report is written for this and for each
additional on-site laboratory evaluation.
53
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1 1.0 Acceptance Criteria
Acceptance criteria for audit sample values are the where:
same for WLS-I as for ELS-I. These criteria are Z is the standard normal variate, having a normal
discussed fully in Section 1 1 of the ELS-I QA plan distribution with a mean of 0 and a variance of 1 .
(Drouse et al., 1986). The limits of the windows are ^ is a variable that has a chi-square distribution
determined by using a t-statistic (t). with r degrees of freedom, and Z and n are
independent.
Z
t = - is a Students t
55
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-------
12.0 Data Management System
The purpose of the data base management system is
to assemble, store, and edit data generated during
WLS-I and during other NSWS surveys. The data
base management system also is used to provide
basic reports of the survey results, to perform certain
statistical analyses, and to provide data security. The
relationship of data base management to other survey
activities is shown in Figure 12-1.
The data are stored in four major data sets: Data
Set 1 - the raw data set, Data Set 2 - the verified
data set, Data Set 3 - the validated data set, and
Data Set 4 - the final data set. These four data sets
make up the WLS-I data base and are discussed in
the following subsections. Individual, system, and file
passwords protect all data sets from unauthorized or
accidental access.
12.1 Data Set 1 - The Raw Data Set
At Oak Ridge National Laboratory (ORNL), the field
data, which are reported on the lake data and
batch/QC forms (forms 1 and 2, respectively), and the
analytical laboratory data, which are reported on
analytical data forms 11, 13, 18, 19, 20, 21, 22, and
23 (see Drouse et al., 1986, Appendix A), are entered
into the raw data base. Data entry operators use the
Statistical Analysis System (SAS) for this purpose.
Analytical data from form 26, which is used only by
the QA staff for confirmation/reanalysis procedures,
are not entered into the raw data set (see Section
12.2). The raw data set includes all analytical results
and data qualifiers (see Table 12-1).
The SAS full-screen editor procedure is used to
provide gross error checking as data are entered. All
data are entered into two separate data sets by two
different operators. For the NSWS data base, a
program (COMPARE) has been developed in SAS to
compare the two data sets and to identify any
inconsistencies. The advantage of this double entry
and comparison process is that entry errors are
removed from the system. The field personnel and
the analytical laboratories also send copies of the field
forms and data packages, respectively, to the
EMSL-LV QA staff for concurrent data analysis.
Thus, receipt of the field and analytical data forms by
the QA staff verifies that all forms have been received
by the data base management personnel.
Changes must be made in the field data if errors are
identified through the daily QA communication with
the field personnel. The checks for identifying errors
are given in Sections 13.1.1 and 13.1.2. If the data in
question have not been entered yet by ORNL, the
changes are included in the raw data set. If the data
have been entered already, the changes are included
in subsequent data sets.
12.2 Data Set 2 - Verified Data Set
When the field and analytical laboratory data are
transmitted through magnetic tapes and the raw data
are made available to the EMSL-LV QA group, all
data are evaluated and verified as described in
Section 13.0. The data are processed by "Automated
Quality Assurance Review, Interactive Users System"
(AQUARIUS), an on-line QA system developed by
the EMSL-LV QA staff. Reports generated by
AQUARIUS range in subject from a complex protolyte
analysis to simple external/internal blank checks for
QA purposes. AQUARIUS generates "tuples" that
direct ORNL to mark problem data with flags (given in
Table 12-2), as deemed necessary by the EMSL-
LV QA staff. Tuples are defined as SAS observations
generated by an exception program or manually
created by an auditor, which are intended either to
change or to annotate a value in a copy of Data Set 1
(the raw data set). Because the raw data set is never
changed, a revised data'set (the verified data set) is
generated. Tuples have a fixed number of fields that
specify the batch, the sample, and the variable to be
flagged, modified, or verified. The tuples are sent to
ORNL via magnetic tape and are entered into the
verified data set. Tuples should only have to be
transferred twice, once for initial verification and once
for final verification. The originally reported data
values are maintained in Data Set 1 (the raw data set)
for a historical record.
In addition to the standard QA analyses, AQUARIUS
is used to generate numerous printouts that are
supplied to the QA manager to indicate intra-
laboratory, field interlaboratory, and analytical
interlaboratory bias, as well as discrepancies in
blanks, duplicates, audits, and other QA/QC samples.
The overall outcome is a verified data set in which
any suspicious values or observations are qualified
with a flag (listed in Table 12-2). When a datum is
not reported, the missing value code "." is assigned
57
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Figure 12-1. Data management, Western Lake Survey - Phase I.
/F.eldB^eS.esA
\^ Laboratory J
Laboratones
/ Data Entry by
7 ORNL
Batch Reports,
Range Checks
/
4
^
W
^
Verification by
FM^I I \/ OA
Preliminary
ERL-C
^^^^•n
—^,
^
Validation by
ERL-C
and by EMSL-C
* Data Tracing System
(in numeric fields only) with an accompanying data
qualifier for explanation. The QA personnel coordinate
with the field bases and with the analytical
laboratories to make all appropriate corrections in the
data.
12.3 Data Set 3 - The Validated Data
Set
The validation process begins in tandem with the
verification process. When ORNL provides the ERL-
C staff with a computerized version of the verified
data set through the computing facility at Research
Triangle Park (RTF), North Carolina, the validation
process can be completed. The validation process
increases the overall integrity of the data base by
using all the QA/QC information available to evaluate
all data for internal and regional consistency.
In the validation process, known relationships in
aquatic chemistry and limnology are used to identify
intrasite sample inconsistencies within data for a set
58
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Table 12-1. National Surface Water Survey Laboratory/Field Data Qualifiers (TAGS),
Western Lake Survey - Phase I
Qualifier Indicates
A Instrument unstable
B Redone, first reading not acceptable
C Instruments, sampling gear not vertical in water column
D Slow stabilization
E Hydrolab cable too short
F Result outside QA criteria (with consent of QA manager)
G Result obtained from method of standard additions
H Holding time exceeded criteria
J Result not available; insufficient sample volume shipped to laboratory from the field
K Result not available; entire aliquot not shipped
L Not analyzed because of interference
M Result not available; sample lost or destroyed by laboratory
N Not required
P Result outside QA criteria, but insufficient volume for reanalysis
Q Result outside QA/QC criteria
R Result from reanalysis
S Contamination suspected
T Leaking container
U Result not required by procedure; unnecessary
V Anion/cation balance outside criteria because of high DOC
W % Difference (%D) calculation (Form 14) outside criteria because of high DOC
X Available for miscellaneous comments in the field only
Y Available for miscellaneous comments in the field only
Z Available for miscellaneous comments in the field only
< Measurements taken at < 1.5 m (in situ lake measurement only)
of variables. Intersite validation consists of comparing
single site values with values for adjacent sites within
a region. Data for groups of sites are compared and
mapped to check for consistency. The validation
process is summarized further in Section 14.0. After
undergoing this reviewing process, the data, lake by
lake, are transferred to the validated data base.
12.4 Data Set 4 - The Final Data Set
The calculation of population estimates is difficult if
the data set contains missing values (Linthurst et al.,
1986). To resolve the problems in the validated data
set that result from missing values, a final data set
(Data Set 4) is prepared. This data set is modified by
averaging the field routine/duplicate pair values that
are within desired precision limits and by replacing
analytical values determined to be in error during
validation. The values used for substitution are
determined in one of several ways, as described in
Section 15.0.
59
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Table 12-2. Data Qualifiers (FLAGS) for the Verified Data Set, Western Lake Survey - Phase I
AO Anion/cation percent ion balance difference (%IBD) is outside criteria for unknown cause.
A1 Anion/cation percent ion balance difference (%IBD) is outside criteria because of nitrate contamination
A2 Anion/cation percent ion balance difference (%IBD) is outside criteria because of anion (other than nitrate)
contamination.
A3 Anion/cation percent ion balance difference (%IBD) is outside criteria because of cation contamination.
A4 Anion/cation percent ion balance difference (%IBD) is outside criteria because of unmeasured organic
protolytes (fits Oliver Model).
A5 Anion/cation percent ion balance difference (%IBD) is outside criteria because of possible analytical
error - anion concentration too high (flag suspect anion)
A6 Anion/cation percent ion balance difference (%IBD) is outside criteria because of possible analytical
error - cation concentration too low (flag suspect cation)
A7 Anion/cation percent ion balance difference (%IBD) is outside criteria because of possible analytical
error - anion concentration too low (flag suspect anion).
A8 Anion/cation percent ion balance difference (%IBD) is outside criteria because of possible analytical
error - cation concentration too high (flag suspect cation)
BO External (field) blank is above expected criteria for pH, DIC, DOC, conductance, ANC, and BNC
determinations
B1 Internal (laboratory) blank is >2 x CRDL for pH, DIC, DOC, conductance ANC, and BNC determinations.
B2 External (field) blank is above expected criteria and contributed >20% to sample values (This flag is not
used for pH, DIC, DOC, ANC, or BNC determinations )
83 Internal (laboratory) blank is >2 x CRDL and contributes > 10% ;o the sample concentrations (This flag is
not used for pH, DIC, DOC, ANC, or BNC determinations )
B4 Potential negative sample bias based on internal (laboratory) blank data
B5 Potential negative sample bias based on external (field) blank data.
CO Percent conductance difference (%CD) is outside criteria for unknown cause (possible analytical error - ion
concentration too high)
C1 Percent conductance difference (°oCD) is outside criteria because of possible analytical error - anion
concentration too high (flag suspect anion)
C2 Percent conductance difference (%CD) is outside criteria because of anion contamination
C3 Percent conductance difference (%CD) is outside criteria because of cation contamination.
C4 Percent conductance difference (%CD) is outside criteria because of unmeasured organic ions (fits Oliver
Model).
C5 Percent conductance difference (%CD) is outside criteria because of possible analytical error in
conductance measurement.
C6 Percent conductance difference (%CD) is outside criteria because of possible analytical error - anion
concentration too low (flag suspect anion)
C7 Percent conductance difference (%CD) is outside criteria because of unmeasured protolyte ions (does not
fit Oliver Model)
C8 Percent conductance difference (%CD) is outside criteria bacause of possible analytical error - cation
concentration too low (flag suspect cation)
C9 Percent conductance difference (%CD) is outside criteria because of possible analytical error - cation
concentration too high (flag suspect cation).
D2 External (field) duplicate precision exceeded the maximum expected percent relative standard deviation
(%RSD), and the routine and duplicate sample concentrations both were > 10 x CRDL
D3 Internal (laboratory) duplicate precision exceeded the maximum contract-required percent relative standard
deviation (%RSD), and the routine and duplicate sample concentrations both were 2 10 x CRDL
FO Percent conductance difference (°'cCD) exceeded criteria when Hydrolab conductance value was substituted.
F1 Hillman/Kramer protolyte analysis program indicates field (Hydrolab) pH problem when Hydrolab pH value
is substituted for field laboratory pH
F2 Hillman/Kramer protolyle analysis program indicates unexplained field pH or DIC problem when Hydrolab
pH value is substituted for field laboratory pH.
(continued)
60
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Table 12-2 (Continued)
F3 Hillman/Kramer protolyte analysis program indicates field problem - field laboratory pH
F4 Hillman/Kramer protolyte analysis program indicates field problem - field laboratory DIC
F5 Hillman/Kramer protolyte analysis program indicates unexplained field problem - pH or DIC
HO The maximum holding time criteria were not met.
L1 Instrumental detection limit (IDL) exceeded CRDL and sample concentration was < 10 x IDL.
MO The method used to obtain the value is not acceptable according to the IFB contract.
NO Audit sample value exceeded upper control limit.
N1 Audit sample value was below lower control limit.
PO Hillman/Kramer protolyte analysis program indicates laboratory problem - initial pH (ANC)
P1 Hillman/Kramer protolyte analysis program indicates laboratory problem - initial pH (BNC).
P2 Hillman/Kramer protolyte analysis program indicates laboratory problem - unexplained - initial pH (ANC
or BNC)
P3 Hillman/Kramer protolyte analysis program indicates laboratory problem - initial DIC.
P4 Hillman/Kramer protolyte analysis program indicates laboratory problem - air-equilibrated pH or DIC
P5 Hillman/Kramer protolyte analysis program indicates laboratory problem - unexplained - initial pH or
DIC
P6 Hillman/Kramer protolyte analysis program indicates laboratory problem - ANC determination
P7 Hillman/Kramer protolyte analysis program indicates laboratory problem - BNC determination
Q1 QCCS value was above contractual criteria.
O2 QCCS value was below contractual criteria
03 Insufficient number of QCCSs were measured
Q4 No QCCS analysis was performed
Q5 Detection limit QCCS was not 2 to 3 times the CRDL, and measured value differed more than 20 percent
from theoretical concentration.
SO Matrix spike percent recovery (%REC) was above contractual criteria
S1 Matrix spike percent recovery (%REC) was below contractual criteria.
XO Questionable data point. Recommendation is to remove point from subsequent data sets and from any
statistical analyses.
X1 Extractable aluminum (ALEX) > Total aluminum (ALTL) by 0 01 mg/L or more (ALEX > 3 X CRDL and
ALEX > ALTL by 0 01 mg/L or more)
61
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73.0 Data Evaluation and Verification
Data review begins with the daily telephone calls
made to each field laboratory and analytical laboratory
(1) to ensure that QA/QC guidelines are being
followed, (2) to ensure that samples are being
handled and analyzed properly, (3) to obtain current
sample data, and (4) to discuss problems that may
occur during analyses. The primary objective of these
calls is to identify and resolve issues quickly, before
they affect data quality or interfere with the
completion of the survey.
Preliminary sample data are obtained verbally, by
computer, or by TELEFAX from the different
laboratories. The preliminary data are evaluated by
comparing the QA sample data to acceptance criteria.
Responsible parties are notified of problems, and all
interactions are recorded in bound notebooks. If
necessary, a letter of documentation is sent.
As the field and analytical laboratory data are
received by the EMSL-LV QA staff, all data are
evaluated on the basis of the available QA/QC
information. The established and organized review
process described here is used for this process. The
objective of the data verification process is to identify
data of unacceptable quality and to correct them, flag
them, or target them for possible sample reanalysis or
for elimination of the data from future data sets.
Computer programs have been developed to
automate this process as much as possible. Each
batch of data is evaluated on a sample-by-sample
basis, as described in the following subsections.
13.1 Field Data Review
As a result of the complexities involved in this survey,
such as the calibration study, the WLS-I data require
more extensive review than did the ELS-I data. The
two data forms filled out by field personnel are
reviewed individually for completeness of data, and
then the two forms are compared.
13.1.1 Lake Data Form
The following checks are required on data on the lake
data form:
• Hydrolab Calibration Data - Compare pH and
conductance calibration data on the lake data
form to data on the Hydrolab calibration forms to
ensure that initial calibration, initial QCCS, and
final QCCS criteria are met; if the criteria are not
met, insert appropriate data qualifiers.
• Stratification - Check that stratification data
were collected if the temperature at the surface
of the lake minus the temperature at the bottom
was greater than 4°C.
• Map Coordinates - Check that the loran-C
readings match the map coordinates.
• Site Drawing - Check that the lake outline is
drawn, that the sample site and any inlets or
outlets are marked, and that the map elevation
and altimeter readings are noted.
• Signatures - Check that all required signatures
are present.
• Secchi Disk Transparency - Check that the
Secchi disappearance depth is greater than or
equal to the Secchi reappearance depth.
• Conversion Factors - Check that the site depth
has been converted correctly from feet to
meters.
• Comments - Check if any comments noted by
the sampling crew need additional explanations
or if data qualifiers need to be applied to the
data.
13.1.2 Batch/QC Form
The following checks must be completed on the
batch/QC form:
• Trailer Duplicate - Check that this sample is
recorded on the bottom of the batch/QC form
and that it has a sample code of TD with a
sample ID of Dup. This sample should have a
lake ID that matches a routine lake sample ID
within that batch.
• Field Laboratory QA Samples - Evaluate results
of DIG, pH, turbidity, and true color
measurements of field routine duplicate pairs in
accordance with associated acceptance criteria
for precision; evaluate field audit samples in
accordance with associated acceptance criteria;
check results of turbidity and true color
63
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measurements of field and trailer blanks for
indications of contamination.
• Field Laboratory QCCS - Evaluate results of
DIG, pH, turbidity, and true color measurements
of QCCSs in accordance with QCCS criteria.
• Split Codes - Split samples go to ERL-C and
to EMSL-LV. Check that split codes are
correct.
• Dates - Check that date processed and date
shipped are correct. Date shipped is one day
after date processed, except on weekends.
• Analytical Laboratory - Check that the
analytical laboratory to which the batch is
scheduled to be shipped is the correct one. This
is especially important for tracking calibration
study samples.
• Lake ID and Sample Code - Check for
consistency (i.e., that a field duplicate has a field
routine with the same lake ID; that audit samples
are coded properly).
• Signature of Field Laboratory Supervisor -
Check that the form is signed.
• Comments - Check if any comments noted by
the sampling crew need additional explanations
or if data qualifiers need to be applied to the
data.
13.1.3 Comparison of Lake Data Form to
Batch/QC Form
• Identification Numbers and Codes - Check that
the lake IDs, batch IDs, sample IDs, and sample
codes on both forms match.
• Hydrolab pH - Compare the pH reading taken
at 1.5 m (recorded on the lake data form) to the
field laboratory pH reading on the batch form.
• Calibration Study Lakes - Check batch IDs,
sample IDs, lake IDs, and sample codes for
calibration lake samples. Because samples with
the same lake ID are included in more than one
batch, sample codes must be checked carefully;
therefore, an extensive tracking system is
required. The calibration study is discussed in
Section 5.2.
• Data Qualifiers and Comments - Check that
comments are reasonable and that they are
consistent between forms.
• Crew ID - Check for correct transcription of
crew ID from the lake data form to the batch/QC
form.
Data anomalies are reported to the field laboratory
coordinator for review, and data-reporting errors are
transmitted to ORNL to be corrected before the
improper data are entered into the raw data set. All
telephone communications are recorded in bound
notebooks, and data corrections are annotated on the
appropriate forms.
13.2 Analytical Data Review
73.2.7 Preliminary Review of Sample Data
Package
The sample data packages are reviewed for
completeness, internal QC compliance, and
appropriate use of data qualifiers. The Data Package
Completeness Checklist (like that shown in Appendix
F of Drouse et al. (1986) but with an appropriate title
change) is used to ensure consistency in the review
of all data packages. Any discrepancies related to
analytical data are reported to the appropriate
analytical laboratory manager for corrective action. If
discrepancies affect billing or data entry, then the
Sample Management Office (SMO) or ORNL is
notified. Comments provided in the cover letter also
are reviewed to determine their effect on data quality
and the need for any follow-up action by the
laboratory. This data review process is also important
in verifying that the contractual requirements have
been met for the purpose of payment.
73.2.2 Review of QA/QC Data
The analytical data reported on data forms are
entered into the raw data set by ORNL as the data
packages are received. A magnetic tape containing
raw data is sent to the EPA for the IBM 3081 at the
National Computer Center (NCC) at RTP. Each tape
received by the NCC tape library is given a volume
serial number and a BIN number that indicates the
physical location of the tape. The tape is loaded
remotely by the EMSL-LV QA staff, and the
exception-generating programs listed in Table 13-1
are run.
The WLS-I Verification Report (like that shown in
Appendix G of Drouse et al. (1986) but with an
appropriate title change) is completed. Outputs from
exception reports, original data, and field notebooks
are used in this process. The verification report is a
worksheet designed to guide the auditor
systematically through the verification process. It
explains how to flag data, tracks data resubmissions
and reanalysis and confirmation requests, lists the
steps used to help explain the QA exceptions,
summarizes all modifications (e.g., value changes) to
the raw data base, and lists all verified sample data.
One hundred percent of the analytical data are
verified, sample by sample and for the batch as a
whole. A routine lake sample has to meet the
anion/cation percent ion balance difference (%IBD)
and the percent conductance difference (%CD)
criteria in order to be verified, unless the discrepancy
can be explained by the presence of organic species
64
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Table 13-1. Exception-Generating and Data Review Programs, Western Lake Survey -
Phase I
Program
Type
Exception-Generating Programs:
1 = Audit Sample Summary (FL.FN)
2 = Laboratory/Field Blank Summary (BH.BG.TB)
3 = Field Duplicate Precision Summary (R/D Pairs)
4 = Instrumental Detection Limit Summary (All Species)
5 = Holding Time Summary (All Species)
6 = Percent Conductance Difference Calculations (All Species)
7 = Anion/Cation Balance Calculations (All Species)
8 = Internal Laboratory Duplicates
9 = Matrix Spike Summary
10 = Protolyte Analysis (DIG, DOC, pH, ANC, and BNC Data Evaluation)
11 = Reagent/Calibration Blanks and QCCS
12 = Comparison of Total Aluminum to Extractable Aluminum
Data Review Programs:
1 = Raw Data Listing - Format for QA Manager
2 = Complete Raw Data Listing - Format for Audit Staff
3 = Comparison of Form 1 and Form 2
4 = Comparison of Form 2 and Form 11
5 = QA/QC Flag Summary
6 = Modified Gran Analysis Program
(pH and DIC)
(pH and DIC)
(as indicated by the protolyte analysis program) or by
an obvious correctable reporting error.
Additional flags are applied to a given parameter for
all the samples within the batch when the batch QA
sample data do not meet the acceptance criteria for
QA samples such as field blanks, field duplicates, or
field audit samples. Each sample in the batch is also
flagged by parameter if internal QC checks such as
matrix spike recovery, calibration and reagent blank
analytical results, internal (analytical laboratory)
duplicate precision, instrumental detection limits,
QCCS analytical results, and holding times do not
meet specifications. The final source of flags is the
protolyte analysis program. A detailed description of
the evaluation of DIC, DOC, pH, ANC, and BNC data
by the protolyte analysis program is given in Section
13.2.4. In all cases, the flags that are generated by
the computer programs are reviewed by the auditor
for reasonableness and consistency before the flags
are entered into the data base.
73.2.3 Computer Evaluation of DIC, DOC, pH,
ANC, and BNC Data
An evaluative computer program performs data
checks and uses carbonate equilibria and DOC data
to identify analytical error and the source of protolytes
(acidic or basic species) in the sample. The DIC, pH,
ANC, and BNC data are rigorously evaluated in light
of known characteristics of carbonate equilibria. DOC
data are introduced to the evaluation with the use of a
theoretical model (the Oliver model-see Section
13.2.32) to predict characteristics of the more
complex system. The overall process of data
evaluation based on carbonate equilibria is
summarized below.
13.2.3.1 Redundant Alkalinity Checks for pH and
DIC --
Evaluations of carbonate equilibria indicate that
alkalinity is not affected by changes in dissolved CO2
concentration. Furthermore, alkalinity can be
calculated from carbonate equilibria if the DIC and pH
are known. A theoretical alkalinity, C, is calculated
from each of the three pH/DIC pairs:
C-| = pH/DIC of "closed system" syringe
samples (field laboratory)
C2 = pH/DIC of "open system" samples
(analytical laboratory)
£3 = pH/DIC of "air-equilibrated system"
samples (analytical laboratory)
The third data pair (C$) is obtained on an aliquot that
has been equilibrated with standard air (300 ppm
CO2). If there is no analytical error, the three
calculated alkalmities should agree within
65
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experimental error. The precision for calculated
alkalinity values of less than or equal to 100 peq/L
should be within ±10 ueq.L and within ±10 percent
for calculated alkalinity values greater than 100 ueq/L.
The precision windows are based on the estimated
precision of the pH and DIG measurements used in
the calculations. If this comparison indicates a
potential analytical error (i.e., the precision limit is
exceeded), the redundant pH and DIG values are
compared to identify the source of error. Further
evaluation of the QAQC information for the individual
data pairs usually identifies one of the pH or DIG
measurements within the outlier pair as the source of
error. Because of the redundancy in measurement,
for every sample that is analyzed, an acceptable pH
or DIG value from one of the data pairs should be
available to the data user.
13.2.3.2 Verification of Measured ANC --
The measured ANC is evaluated by comparing it to
the average of the acceptable calculated values for
alkalinity determined during the evaluation of pH and
DIG.
Carbonate Systems - For a true carbonate system,
the measured ANC should equal (within experimental
error) the calculated alkalinity. The difference
between measured ANC and the calculated alkalinity
should be within ±15 ueq L for calculated alkalmities
less than or equal to 100 ueq.L, and within ±10
percent for larger values. If the measured ANC differs
from the calculated alkalinity, an analytical error is
indicated in the titration or in the pH or DIG
measurements.
Mixed Systems - Mixed systems are those
represented by samples that have significant
concentrations of other protolytes in addition to the
carbonate species. In natural waters, organic bases
derived from humic and fulvic acids often are present
and can make a significant contribution to the ANC.
The Oliver model is an empirical method of relating
DOC, pH, and organic protolytes in two ways (Oliver
et al., 1983). The first way relates the total organic
protolyte to DOC, and the second relates the mass
action quotient (pK0) of the organics present to the
sample pH.
DOC and pH are measured in each sample. The
empirical relationships (defined by the Oliver model)
and the measured pH and DOC values are used to
estimate the contribution of organic protolytes to the
measured ANC. The measured ANC should equal,
within experimental error, the sum of the calculated
alkalinity and the estimated organic protolyte
contribution, if it is assumed that significant
concentrations of other (non-organic) protolytes are
not present and if there is no analytical error. The
precision should be within ±15 peq/L for calculated
ANC less than or equal to 100 ueq/L and within ± 10
percent for larger values.
13.2.3.3 Verification of Measured BNC -
BNC, unlike ANC, is affected by changes in dissolved
CO2 concentration. Therefore, evaluation and
verification of BNC data cannot utilize as much
redundancy as that of ANC data. Only the initial pH
and DIG values determined in the analytical laboratory
(data pair C2, see Section 13.2.3.1) can be used to
calculate BNC for comparison with the measured
value. As with ANC, other protolytes can contribute to
the measured BNC. An estimate of CO2-acidity is
calculated from data pairs and carbonate equilibria.
The calculated acidity should equal, within
experimental error, the measured BNC, if no other
protolytes are present. Precision for calculated acidity
values less than or equal to 100 peq/L should be
within ±10 peq L and within ±10 percent for larger
values. If the calculated acidity is greater than the
measured BNC. an analytical error in the pH, DIG, or
BNC determination is indicated.
The pH and DIG measurements are verified by the
previous tests (QA QC redundancy and alkalinity
checks). If the calculated acidity is less than the
measured BNC, the difference may be due to the
presence of other protolytes or to an analytical
measurement error. The Oliver model is used to
evaluate the contribution from organic protolytes.
13.2.3.4 System Check for Total Carbonate -
For a carbonate system, it can be shown that the
sum of alkalinity and acidity equals total carbonate
concentration in the sample. For a mixed system, it
can be shown that the sum of ANC and BNC equals
the total protolyte concentration in the sample. Thus,
as an additional check of the data, the calculated
values of alkalinity and acidity can be combined and
can be compared to the sum of the measured ANC
and BNC. For a carbonate system, the sum of ANC
and BNC should equal, within experimental error, the
total carbonate concentration or the sum of calculated
acidity and alkalinity. If this sum is less than the
calculated total carbonate, an analytical error is
indicated because the two titrations must account for
all carbonate species present in the sample. Other
protolytes or analytical error is indicated if the sum of
ANC and BNC exceeds the calculated total
carbonate. Again, the Oliver model is used to
evaluate the data.
The precision of the total carbonate results should be
within ± 15 nmole/L for total carbonate concentrations
less than or equal to 100 umole/L and within ±10
percent for higher concentrations.
The protolyte analysis program generates flags (Table
12-2) on the basis of the data checks described
above to indicate the source of problems.
66
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13.2.4 Follow-up with Analytical Laboratories
After all data have been reviewed, the analytical
laboratories are requested to submit completed
copies of data reporting forms that were incomplete
when previously submitted, to submit corrections of
previously reported data, to confirm previous results,
and to reanalyze certain samples that do not meet
QA/QC criteria. The analytical laboratories are
directed to respond within a reasonable time so that
the results can be evaluated in time for them to be
useful to the survey.
73.2.5 Preparation and Delivery of Verification
Tapes
The steps identified in sections 13.2.2 through 13.2.4
are followed to identify suspect data and to correct
erroneous data. The information obtained by this
process is accumulated by the EMSL-LV QA staff
and is placed on magnetic tapes, which subsequently
are sent to ORNL. There, the new data are entered
into the raw data set to correct and flag the original
data. These steps may have to be repeated several
times before all the data are verified; however, the
aim is to have only two iterations.
67
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74.0 Data Validation
The system of data validation developed for ELS-I in Section 14 of the ELS-I QA plan (Drouse et
also is used for WLS-I. Data validation is discussed al.,1986). A flowchart of the validation process is
shown in Figure 14-1.
Figure 14-1. Flowchart of the data validation process, Western Lake Survey - Phase I.
(Data Set 2 \
Verified J
\
1
r
Univanate
* Box Plots
* Probability Plots
1
1
r
4
Multivanate
* Principal Component
Analysis
* Cluster Analysis
* Tnlmear Plots
* Multiple Linear
Regression
Bivanate
* Scatter Plots
* Regression
Relational Comparative
Systema
Differenc
r Outliers T ^ r
*r 1 '
* Data Tracking System
c
Flag or
Modify
Values
/ Data Set 3 \
\ Validated I
69
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75.0 Development of a Final Data Set
The calculation of population estimates is difficult if
values are missing from the data set. A final data set
(Data Set 4) is prepared to resolve problems in the
validated data set that result from missing values.
Data Set 4 also is modified by averaging field
duplicate values, substituting for analytical values
determined to be in error during validation (Figure
15-1), and modifying (i.e., adjusting to zero) values
reported as negative (except for ANC and BNC). The
values that have been modified for the final data set
are flagged with the appropriate data qualifiers (see
Table 15-1).
15.1 Missing Data Substitution
Substitution for missing values is done in one of
several possible ways. Values from duplicate samples
are used when available. Redundant analyses are
performed for pH, DIG, and conductance (see Section
13.2.4). Redundant measurements on split samples
(see Section 6.3.2.3.1) are performed for metals and
other elements. If a duplicate measurement is not
available, a comparable measurement is chosen and
is substituted for the missing value. A linear
regression routine is used for this purpose. If
redundant measurements are not available or are not
acceptable, observed relationships with other
variables (e.g., sodium and chloride) are used to
calculate a substitution value from the available data.
The last option for identifying a substitution value is to
use the stratum mean within the subregion. All
substitution values are examined a second time for
acceptability before they are included in the final data
set. Substituted values are flagged as such in the
final data set.
15.2 Averaging of Field Duplicate Pairs
If field duplicate pairs have no validation flags present,
the average of the duplicate pair values is used in the
final data set. Averaged values are flagged in the final
data set.
Table 15-1. Validation Data Qualifiers (Flags) for the Final Data
Set, Western Lake Survey - Phase I
UO Known error based on relationships with other variables or on
impossible values; substitutions were made in Data Set 4.
U1 Value is a substitution, original value was missing.
U2 Value is a substitution, original value was considered to be
in error.
VO Data value represents the average from a duplicate split and
measurement of the lake sample.
V1 Data value is from the duplicate sample and is not averaged
because the regular sample had "WO" flag limitations.
WO Data value has possible measurement error based on relationships
with other variables, has QA violations, or is outside QA
windows for acceptable data.
ZO Original value was less than zero and has been replaced
with zero.
71
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Figure 15-1. Development of Data Set 4, Western Lake Survey - Phase I.
/Data Set /
3 /
No
/Data Set /
4 /
15.3 Treatment of Negative Values
Negative values (for parameters other than ANC and
BNC) that result from analytical calibration bias (i.e.,
instrumental drift) are set to zero. The bias in the
estimate of variance due to this adjustment likely
does not affect data analysis. All negative values
modified in the final data set are flagged.
72
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16.0 References
American Society for Testing and Materials, 1984.
Annual Book of ASTM Standards, Vol. 11.01,
Standard Specification for Reagent Water,
D1193-77 (reapproved 1983). ASTM,
Philadelphia, Pennsylvania.
Best, M. D., S. K. Drouse, L. W. Creelman, and D. T.
Chaloud, 1987. National Surface Water Survey,
Eastern Lake Survey (Phase I -- Synoptic
Chemistry) Quality Assurance Report. EPA 600 4-
86-011. U.S. Environmental Protection Agency,
Las Vegas, Nevada.
Bonoff, M. B., and A. W. Groeger. 1987. National
Surface Water Survey, Western Lake Survey
(Phase I -- Synoptic Chemistry) Field Operations
Report. U.S. Environmental Protection Agency, Las
Vegas, Nevada.
Costle, D. M., May 30, 1979a. Administrator's
Memorandum, EPA Quality Assurance Policy
Statement. U.S. Environmental Protection Agency,
Washington, D. C.
Costle, D. M., June 14, 1979b. Administrator's Policy
Statement, Quality Assurance Requirements for All
EPA Extramural Projects Involving Environmental
Measurements. U.S. Environmental Protection
Agency, Washington, D.C.
Drouse, S. K., D. C. Hillman, L. W. Creelman, and S.
J. Simon, 1986. National Surface Water Survey,
Eastern Lake Survey (Phase I -- Synoptic
Chemistry) Quality Assurance Plan. EPA 600 4-
86-008. U. S. Environmental Protection Agency,
Las Vegas, Nevada.
Hillman, D. C., J. F. Potter, and S. J. Simon, 1986.
National Surface Water Survey, Eastern Lake
Survey (Phase I -- Synoptic Chemistry)
Analytical Methods Manual. EPA 600/4-86-009.
U.S. Environmental Protection Agency, Las Vegas,
Nevada.
Hydrolab Corporation, 1985 (revised). Operation and
Maintenance Manual for Hydrolab Surveyor II.
Hydrolab Corporation, Austin, Texas.
Kerfoot, H. B., and M. L. Faber, 1987. National
Surface Water Survey, Western Lake Survey
(Phase I -- Synoptic Chemistry) Analytical
Methods Manual. U.S. Environmental Protection
Agency, Las Vegas, Nevada.
Landers, D. H., J. M. Eilers, D. F. Brakke, W. S.
Overton, P. E. Kellar, M. E. Silverstem, R. D.
Schonbrod, R. E. Crowe, R. A. Linthurst, J. M.
Omernik, S. A. Teague, and E. P. Meier, 1987.
Characteristics of Lakes in the Western United
States. Volume I. Population Descriptions and
Physico-Chemical Relationships. EPA/600/3-
86 054a. U.S. Environmental Protection Agency,
Washington, D.C.
Linthurst. R. A., D. H. Landers, J. M. Eilers, D. F.
Brakke, W. S. Overton, E. P. Meier, and R. E.
Crowe, 1986. Characteristics of Lakes in the
Eastern United States. Volume I. Population
Descriptions and Physico-Chemical Relationships,
EPA 600 4-86-007a. U.S. Environmental
Protection Agency, Washington, D.C.
Morris, F. A., D. V. Peck, M. B. Bonoff, and K. J.
Cabbie, 1986 National Surface Water Survey,
Eastern Lake Survey (Phase I -- Synoptic
Chemistry) Field Operations Report. EPA 600/4-
86-010. U.S. Environmental Protection Agency,
Las Vegas, Nevada.
Morris, F. A., D. V. Peck, D. C. Hillman, K. J. Cabbie,
S. L. Pierett, and W. L. Kinney, 1985. National
Surface Water Survey, Western Lake Survey
(Phase I) Field Training and Operations Manual,
Internal Report. U.S. Environmental Protection
Agency, Las Vegas, Nevada.
Oliver, B. G., E. M. Thurman, and R. K. Malcolm,
1983. The Contribution of Humic Substances to
the Acidity of Colored Natural Waters. Geochim.
Cosmochim. Acta, v. 47, pp. 2031-2035.
Peck, D. V., R. F. Cusimano, and W. L. Kinney, 1985.
National Surface Water Survey, Western Lake
Survey (Phase I - Synoptic Chemistry) Ground
Sampling Training and Operations Manual, Internal
Report. U.S. Environmental Protection Agency, Las
Vegas, Nevada.
U.S. Environmental Protection Agency, 1980. Interim
Guidelines and Specifications for Preparing Quality
Assurance Project Plans. QAMS-005/80. U.S.
Environmental Protection Agency, Washington,
D.C.
73
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Appendix
Form Used in On-Site Evaluation of Ground Crews,
Western Lake Survey - Phase I
Western Lake Survey Ground Crew Audit Questionnaire 1.2
Subregion
Field Base Location
Remote Site Location
EPA Base Coordinator
USFS Field Manager
Dates
Auditors
Note 1. Circle one or more contact modes on page heading:
R = radio
T = transfer point
L = laboratory or base (sample inspection, no contact)
P = personal contact (on site, transfer point, or laboratory)
Note 2. In left margin indicates questions to be asked during radio contact time.
75
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GROUND CREW STATISTICS - P
Crew ID
Samplers' Names
Agency
Academic Training
Experience Type
and Years
76
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SAMPLERS' NAMES.
CREW ID
DATE
STAGING AREA - P
Item
Has adequate space been provided for predeparture
activities?
Are facilities clean and organized?
Is equipment clean and organized?
Is all equipment operational?
Has the thermistor been through a two-point calibration
check? Results?
Yes
No
Comments
Notes:
77
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SAMPLERS' NAMES.
CREW ID
DATE
EN ROUTE ACTIVITIES - P - R - T
Item
* Are the maps adequate?
* Are there any problems in locating lakes?
Are the field data forms and notebooks understood?
Correctly filled out? Transcriptions verified?
Are identifications of target lakes verified? How?
Are pack and riding animals adequate for safe
transportation of personnel and gear?
Yes
No
Comments
Notes:
78
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SAMPLERS' NAMES
DATE
CREW ID
PREPARATION - P
Item
Are checklists followed for loading equipment?
Is equipment organized and easily accessible on pack
animals.
Is equipment stored properly to prevent injury or damage
during transport?
Are excursion plans made? Adequate? Understood by all
personnel?
Do the field manager and base coordinator know where crew
is at any given time?
Is communication between field base and field crew
adequate?
Are check-in times prearranged? Are there deviations from
the times? If so, explain.
Has trip departure been delayed significantly for any reason?
Reasons?
Yes
No
Comments
Notes:
79
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SAMPLERS' NAMES.
CREW ID
DATE
ON-SITE SAMPLING - P- R - T
Item
* Are there problems finding the deepest sampling site while
on lake?
Are the sounding, Secchi, and thermistor lines adequate?
* Are the procedures clear and easily followed?
Are required procedures for blanks and duplicates
followed?
Are required safety procedures followed?
'Are there any problems in obtaining samples?
Are adequate volumes of sample being taken?
Are procedures being followed that avoid contamination?
Are rinse procedures followed correctly?
Are samples stored correctly?
Are appropriate comments being recorded in logbook?
Form 1?
Yes
No
Comments
(continued)
80
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SAMPLERS' NAMES
DATE
CREW ID
ON-SITE SAMPLING - P - R - T (Continued)
Item
Are all labels filled our correctly?
* Is there effective coordination between the sampling crew
and the field laboratory?
Are samples arriving at the field laboratory within required
time?
Are there any problems loading equipment on horses or
llamas? On rafts?
How long did finding the deep site take?
Was 10 minutes allowed for pH strip development?
Were there any problems with air bubbles?
Were there any problems with cables?
Yes
No
Comments
81
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SAMPLERS' NAMES.
CREW ID
DATE
THERMISTOR GENERAL - P - R
Item
Are copies of the operations manual available?
Is the instrument cleaned and packed properly?
Are all personnel capable of routine maintenance?
Troubleshooting meter problems?
Have any maintenance problems occurred?
Are adequate spare parts available?
Is meter performing well?
Are there any continuous problems with the meter?
Have there been any deviations from standard procedures?
Describe.
Were there any problems in determining stratification?
What were the meter deviations from field thermometer?
Were temperature QC checks performed at each lake?
Yes
No
Comments
Notes:
82
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SAMPLERS' NAMES
DATE
CREW ID
ACTIVITIES FOLLOWING SAMPLING - L - P
Item
Are samples packed properly at lake site?
Is equipment packed properly after sampling?
Are samples transferred properly at transfer point?
Are sufficient supplies provided at transfer point?
Are supplies being requested in sufficient time to avoid
delays.
Is sample tracking and custody form properly completed?
Are cooler temperatures being recorded?
Are gel packs arriving from field still frozen?
Were cooler temperatures spot-checked when coolers
arrived at field base? What were the temperatures? Are
they recorded properly?
Were data forms checked for problems? Were they signed
by field manager?
Yes
No
Comments
83
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SAMPLERS' NAMES
DATE
CREW ID
POST SAMPLING ACTIVITIES - L - P
Item
What was the elapsed time between sample collection and
laboratory receipt?
Were phone check-ins received at field base?
Were any calibration lakes sampled? Which?
How were they identified as calibration lakes?
Were the samplers aware that the lake was a calibration
lake?
Yes
No
Comments
Notes:
84
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