vxEPA
United States
Environmental Protection
Agency
Office of Research and
Development
Washington, D.C. 20460
NERL-LV01-065
September 2001
Distributions of Airborne
Agricultural Contaminants
Relative to Amphibian
Populations in the Southern
Sierra Nevada, California
Research Plan
259LEB01.RPT * 9/18/01
-------
NERL-LV01-065
September 2001
Distributions of
Airborne Agricultural Contaminants
Relative to Amphibian Populations
in the Southern Sierra Nevada, California
Research Plan
by
David F. Bradford
Edward M. Heithmar
Chad L. Cross
Beth Gentry
Georges-Marie Momplaisir
Maljha S. Nash
Nita Tallent-Halsell
Lee Riddick
Charlita Rosal
Katrina E. Varner
U.S. EPA
National Exposure Research Laboratory
Environmental Sciences Division
Las Vegas, NV
September 2001
-------
Acknowledgments
The contributions of the following individuals to the development of this draft Research Plan are
gratefully acknowledged: Harold Werner and Annie Esperanza of the Sequoia and Kings Canyon
National Parks for advice and assistance on park issues and logistics; Randy Segawa of the California
Division of Pesticide Regulations for extracting relevant pesticide usage reports from that Division's
database; Kevin Kelly of the U.S. Bureau of Reclamation and Tony Ethier of Axys Group for advice on
field extraction of pesticides and for the loan of Infiltrex 100 extraction devices; Wally Jarman and
Theresa Lowe of the University of Utah for providing in-depth descriptions and demonstrations of their
analytical chemistry methods; David Donald of Environment Canada, William Foreman and Michael
Majewski of the U.S. Geological Survey, Shane Snyder of the Las Vegas Valley Water District, Lantis
Osemwengie of this laboratory, and Jules Blais of the University of Alberta for advice on field and
analytical chemistry methods; Dixon Landers of the U.S. Environmental Protection Agency for
discussions on potential collaboration regarding distributions of pesticides in alpine ecosystems; Thomas
Holsen of Clarkson University for advice on deposition monitoring; and Elizabeth Plymale of the U.S.
Forest Service for discussions related to coordination with the Sierra Nevada Conservation Framework.
We also thank Thomas Cahill, Lara Hansen, Walter Jarman, Dixon Landers, and James Seiber for critical
review of an earlier version of the plan.
-------
Notice
The U.S. Environmental Protection Agency (EPA), through its Office of Research and Development,
developed this research plan. This document has undergone external and EPA peer review, and has been
approved for publication. Mention of trade names and commercial products does not constitute
endorsement or recommendation by the EPA for use.
-------
Abstract
The Sierra Nevada mountain range lies adjacent to one of the heaviest pesticide use areas in the
USA, the Central Valley of California. Because of this proximity, concern has arisen that agricultural
pesticides, in addition to other contaminants, are adversely affecting the natural resources of the Sierra
Nevada. Transport and deposition of pesticides from the Central Valley to the Sierra Nevada has been
documented, and several lines of evidence have implicated pesticide drift from the Central Valley as a
causal factor in the dramatic population declines of four amphibian species in the Sierra Nevada.
This study focuses on contaminants in lakes at high elevation in the southern Sierra, an area where
unexplained population declines of one species, the mountain yellow-legged frog, have been dramatic.
The southern Sierra is of particular interest because air pollution in the Central Valley and Sierra is
generally greatest in the south, watersheds in the southern Sierra differ substantially in their proximity to
the Central Valley, and the region includes large areas where the mountain yellow-legged frog has
completely disappeared and other areas where large numbers remain.
The goals of this study are to: (1) describe the temporal and spatial patterns of distribution of more
than 30 chemical contaminants, especially agricultural pesticides (i.e., insecticides and herbicides), all of
which are expected to occur in very low concentrations; (2) identify the topographic and spatial attributes
of the landscape that influence contaminant distributions (e.g., upslope air flowpath distance from the
Central Valley, and elevation); and (3) determine whether there is an association between contaminant
distributions and unexplained population extinctions of the mountain yellow-legged frog. We will
conduct a study of temporal variation of contaminant concentrations in six lakes in three major
watersheds from approximately April of 2002 through autumn of 2002. Media sampled will be the snow
pack, lake water, sediment, semi-permeable membrane devices suspended in lake water, and possibly dry
deposition from the atmosphere. In 2003 we will conduct a spatial survey of contaminants in at least 60
lakes in four major watersheds over a 130-km segment of the southern Sierra. We will also collect
tadpoles of the ubiquitous Pacific treefrog for determination of acetylcholinesterase activity.
Suppression of activity of this neurological transmitter hydrolase has been used as an indicator of
exposure to pesticides. Results of the spatial survey of contaminants will be used in an analysis of the
current and former distributions of the mountain yellow-legged frog and Pacific treefrog based on results
of ongoing biological surveys for amphibians, fish, and habitat characteristics in 3200 water bodies in
Sequoia and Kings Canyon National Parks. We will also analyze lake water and other media for
contaminants no longer used in the Central Valley. Some of these may be transported from other
continents, and some may be selectively deposited at the higher elevations.
IV
-------
Table of Contents
Acknowledgments ii
Notice iii
Abstract iv
List of Tables vii
List of Figures viii
Section 1 Background 1
1.1 Rationale for Study 1
1.2 Pesticide Transport and Deposition in the Southern Sierra 2
1.3 Pesticide Distributions in the Southern Sierra 3
1.4 Focus on Lake Ecosystems in the Southern Sierra 4
1.5 Multiplicity of Factors Possibly Causing Amphibian Population Declines 5
Section 2 Goals and Objectives 6
2.1 Goals 6
2.2 Objectives and Hypotheses 7
Section 3 General Approach 9
3.1 Overall Study Design 9
3.2 Study Area and Amphibians 9
3.3 Target Media 11
3.4 Target Analytes 12
Section 4 Contaminant Temporal Variation Study 14
4.1 Study Sites 14
4.2 Study Design 14
Section 5 Contaminant Spatial Distribution Survey 16
5.1 Study Sites 16
5.2 Study Design 17
Section 6 Biological Surveys 18
Section 7 Sampling and Measurement Methods 19
7.1 Methods for Active Field Sampling and Determination of Contaminants
in Lake Water 19
7.2 Passive Sampling Methods 22
7.3 Contaminants in Snow 22
7.4 Contaminants in Bed Sediment 22
-------
99
7.5 Contaminants in Deposition z^
7.6 Tadpole Cholinesterase Activity 23
7.7 Ancillary On-site Environmental Data 23
7.8 Landscape Metrics and Other Variables 24
7.9 Field Logistics and Training 24
Section 8 Data Management and Analyses 26
8.1 Data Management 26
8.2 Statistical Analyses 26
Section 9 Permits and Approvals 28
9.1 Permits and Permissions 28
9.2 Justification for Helicopter Support 28
Section 10 Quality Assurance 29
Section 11 Schedule 30
Section 12 Personnel and Responsibilities 32
Section 13 Facilities, Equipment, and Other Resources 33
Section 14 Anticipated Products 34
Section 15 Literature Cited 35
Appendix A Patterns of Surface Air Movement in the San Joaquin Valley and
Southern Sierra Nevada 42
Appendix B Additional Selection Criteria for Target Analytes 44
Appendix C Use Patterns of Six Organophosphorus Pesticides in the San Joaquin Valley
Near the Study Area 46
Appendix D Resumes of Participants 49
Appendix E Environmental Chemistry Branch Facilities/Instrumentation 71
VI
-------
List of Tables
Table 1. Tentative list of 31 primary target analytes 13
Table 2. Schedule for contaminant temporal variation study, 2002 31
Table 3. Personnel and responsibilities 32
Table B.I. Factors affecting probable detection of primary target compounds listed in Table 1 45
VII
-------
List of Figures
Figure 1. Study area, and upslope flowpath distances from the San Joaquin Valley 1
Figure 2. Lake elevation and upslope flowpath distance from the San Joaquin Valley 4
Figure 3. Distribution of lakes and sampling sites in the study area 10
Figure C.I. Chlorpyrifos use by month and county 46
Figure C.2. Azinphos methyl use by month and county 47
Figure C.3. Diazinon use by month and county 47
Figure C.4. Methidathion use by month and county 47
Figure C.5. Tribufos use by month and county 48
Figure C.6. Phorate use by month and county 48
VIII
-------
Section 1
Background
1.1 Rationale for Study
The Sierra Nevada mountain
range lies adjacent to one of the
heaviest pesticide use areas in the
USA, the Central Valley of
California (Figure 1; McConnell et
al. 1998). Because of this
proximity, concern has arisen that
agricultural pesticides, in addition
to other contaminants, are adversely
affecting the natural resources of
the Sierra Nevada (Cahill et al.
1996). Transport and deposition of
pesticides from the Central Valley
to the Sierra Nevada has been going
on for some time. In the 1960s, an
organochlorine residue of DDT
(DDE) was found in frog tissue
from numerous locations
throughout the Sierra Nevada (Cory
et al. 1970). More recently many
current-use pesticides, primarily
organophosphorus compounds,
have been found at both low and
high elevations in rain, snow, dry-
fall, air, surface water, and tissues
of pine trees, frogs, and fish (Zabik
and Seiber 1993; Aston and Seiber
1997; Dattaetal. 1998; McConnell
etal. 1998; LeNoir et al. 1999;
Sparling et al., in press).
The impetus for the present
study emanates from two types of
information: action levels for
contaminant concentrations, and
Study Area
Bishop
Sequoia/Kings
Canyon N.P.
Upslope Distance
from SJV (km)
10 0 10 20 30 40 Kilometers
Figure 1. Study area, and upslope flowpath distances from the San
Joaquin Valley Each green shaded band indicates an
increment in 25 km from the origin at the junction of the
major river and the nominal boundary between the San
Joaquin Valley and mountains (see Landscape and Other
Metrics section for definitions and computational methods)
1
-------
recent dramatic population declines of several amphibian species. At a high elevation (1920 m) site in
the Kaweah River watershed, concentrations of some current-use pesticides in winter/spring rainwater
were within an order of magnitude of LC50 values for some aquatic indicator organisms, and up to 30% of
the criteria levels for protection of aquatic life (Zabik and Seiber 1993; McConnell et al. 1998).
Moreover, aggregate exposure calculations for the observed mixture of pesticides in surface water near
this site during summer showed that current exposure levels may be harmful to amphipods, although
concentrations were well below the 96-h LC50 values for rainbow trout and stonefly (LeNoir et al. 1999).
Given the unknowns regarding sublethal effects, synergistic effects of multiple contaminants, and
toxicity of degradation products to amphibians (Bridges and Semlitsch 2000), the observed values at sites
many tens of kilometers from the agricultural source are a concern.
Four species of frog inhabiting the Sierra Nevada have dramatically declined in numbers and
distribution during the past several decades, and airborne agricultural contaminants have been suggested
as one of several causal factors (Jennings and Hayes 1994; Drost and Fellers 1996; Sparling et al., in
press). One of these species, the red-legged frog (Rana aurora), was declared a federally threatened
species in 1996, and two others (mountain yellow-legged frog [Rana muscosa] and Yosemite toad [Bufo
canorus}) are currently under review for listing as endangered (U.S. Fish and Wildlife Service 2000a,
2000b). Although there appear to be a number of factors causing the declines of the red-legged frog (a
low-elevation species), proximity to upwind agriculture has been shown to be a significant correlate of
the population declines (Davidson et al., in press). For two other species, the foothill yellow-legged frog
(Rana boylii) at low elevation and the mountain yellow-legged frog at high elevation, proximity to
upwind agriculture was found to be the most significant environmental factor associated with their
declines (Davidson et al., in review). For the three latter species unexplained population declines in the
Sierra Nevada have been most dramatic in the southern Sierra (Bradford et al. 1994b; Jennings and
Hayes 1994), where exposure to agricultural contaminants is thought to be the greatest (see below).
1.2 Pesticide Transport and Deposition in the Southern Sierra
The western slopes of the Sierra Nevada are regularly bathed by surface air from the San Joaquin
Valley (SJV) (Appendix A). Pesticides applied in the SJV can enter the air by drift during application,
and by post application volatilization and erosion (Seiber and Woodrow 1998). Subsequently, pesticides
can be transported in air as small particles, aerosols, or vapors. Downwind deposition may occur either
by wet processes or by dry processes that include particle settling and vapor exchange with surface
foliage, soil, and water (Seiber and Woodrow 1998). Presumably, pesticides deposited by either wet or
dry processes are transported to lakes primarily by surface runoff. Agricultural pesticides are applied at
all times of the year, with considerable variation in chemical use by month, and hence are available for
transport to the Sierra Nevada year round (McConnell et al. 1998; LeNoir et al. 1999).
No data are available to indicate the relative deposition rates of pesticides between summer and
winter, nor between wet versus dry deposition. During the warm months, however, upslope transport of
pollutants from the SJV (Appendix A) dominates the air quality on the western slopes of the southern
Sierra (Carroll and Baskett 1979; Cahill et al. 1996), and dry deposition of pesticides is thought to be the
dominant mode of deposition (Zabik and Seiber 1993; LeNoir et al. 1999). For nitrates and sulfates,
which are transported primarily as aerosols, dry deposition on the western slopes of the Sierra comprises
a substantial fraction of annual deposition (Stohlgren et al. 1991). During summer thunderstorms, which
occur erratically and are typically patchy in distribution, some wet deposition must occur. During late
-------
fall and winter, when most of the annual precipitation occurs, deposition of pesticides in the Sierra
Nevada is thought to occur primarily as wet deposition (Zabik and Seiber 1993; LeNoir et al. 1999). For
much of the winter, air transport to the western slopes of the Sierra Nevada is largely decoupled from air
within the SJV (Appendix A), and winds are dominated by northwesterly prevailing winds rather than
terrain-driven winds (Cahill et al. 1996). During winter storms, which come off the Pacific Ocean, the
inversion in the SJV is broken, air mixing is vigorous, and pollutants are rapidly deposited in
precipitation (Cahill et al. 1996). Because of the synoptic nature of winter storms, pollutant
concentrations in precipitation are relatively constant over large areas, and are generally low (Cahill et al.
1996).
1.3 Pesticide Distributions in the Southern Sierra
Two geographic patterns of distribution of pesticides and other pollutants are prominent on the
western slopes of the Sierra Nevada. First, pollutant concentrations generally increase from north to
south. This has been shown for a variety of pollutants, including fine sulfate and nitrate aerosols,
aerosols from combustion products, fine soil particles, ozone, and several trace metals (Cahill et al.
1996). For pesticides, DDE concentrations in frogs in the 1960s were higher on the western slopes in the
central and southern Sierra than in the northern and eastern Sierra (Cory et al. 1970), and current-use
pesticides appear to show a similar pattern (Sparling et al., in press). This north-south pattern results
largely from the greater upwind sources of pollutants for the southern Sierra than the northern Sierra, and
generally stronger terrain-driven winds in the south due to steeper valley-mountain slopes (Cahill et al.
1996).
The second geographic pattern is a general decrease in pesticide concentrations as a function of
distance/elevation from the SJV. Several studies have been done in the Kaweah River watershed along a
distance/elevation transect extending from near the edge of the SJV (ca. 300 m elevation) up to about
2040 m elevation and 32 km from the edge of the SJV. As pesticide residues move with wind currents
from the SJV into the mountains, pesticides are removed from the air by dilution, degradation, and
deposition, with dilution having the largest effect (Shair 1995; Aston and Seiber 1997). Thus, pesticide
concentrations have been found to decrease with distance/elevation during summer for 24-hour air
samples, dry deposition, and pine needles, and during winter/spring for precipitation (Zabik and Seiber
1993, Aston and Seiber 1997; McConnell et al. 1998; LeNoir et al. 1999). Interestingly, for surface
water this pattern of decrease with distance/elevation was evident only for the single sample collected at
3320 m elevation in the Kaweah watershed (about 45 km from edge of SJV) and another sample in the
Kings River watershed at 3230 m and over 70 km from the SJV (LeNoir et al. 1999). Pesticide
concentrations in surface water did not differ among sites at elevations < 2040 m (LeNoir et al. 1999).
Although the reduction in concentrations between 2040 and > 3200 m was striking, there is no evidence
that these differences result from "different air masses." Evidence for such a separation has been
observed during summer only during occasional synoptic meteorological events (Ewell et al. 1989).
Moreover, tracer studies during typical summer conditions in the Kaweah watershed showed that upslope
air transport operates at a relatively constant velocity up to the highest elevations sampled (3210 m), with
tracer dilution occurring en route (Shair 1995).
Pesticide concentrations in the Sierra are also influenced by application rates in source areas in the
SJV. In general, pesticide concentrations in air, dry deposition, and surface water in the Kaweah River
watershed correspond with the seasonal pattern of pesticide application in nearby portions of the valley
-------
(LeNoir et al. 1999). The absolute magnitude of variation in air concentration for one of the more
common pesticide residues, chlorpyrifos oxon, was less than an order of magnitude from early June
through mid October at the 1920-m site (Aston and Seiber 1997).
1.4 Focus on Lake Ecosystems in the Southern Sierra
This study focuses on the western slopes of the southern Sierra Nevada because pesticide exposure is
expected to be greatest in this region, and because unexplained disappearances of amphibian populations
have been conspicuous in this area. Moreover, several factors likely to influence terrain-driven air
transport are more varied within this area than anywhere else in the Sierra. These factors include
mountain-valley slopes, proximity to the Central Valley, and elevation. For example, the upslope
pathway from the edge of the SJV is only about 60 km to subalpine lakes in the Kaweah River watershed,
yet it is about 120 km to lakes a few kilometers away in the upper Kings River watershed, and nearly 200
km to lakes a few kilometers away in the upper Kern River watershed (Figures 1 and 2). The study
focuses on lake ecosystems for sampling because the thousands of lakes in the southern Sierra comprise a
major aquatic resource, and lakes constitute the primary habitat in the southern Sierra for the mountain
yellow-legged frog. Lakes in this region are almost entirely confined to elevations above 2700 m, where
almost no sampling has been done for current-use pesticides or contaminant transport processes.
3600-
3400-
c
B 3200 H
CD
_
LLJ
3000
2800-
75
50 75 100 125 150 175 200
Upslope Flowpath Distance from S.J. Valley (km)
* San Joaquin A Kings A Kaweah T Kern
Figure 2. Lake elevation and upslope flow/path distance from the San Joaquin Valley
(see Figure 1). Data are for lakes larger than 0.5 ha, and between 2740 and
3660 m elevation. Total number of lakes is 1330 (319 for San Joaquin, 57 for
Kaweah, 699 for Kings, and 255 for Kern). Number of lakes is slightly
overestimated primarily because the source coverages did not distinguish
between lakes and marshes shown on USGS 7.5' maps.
-------
1.5 Multiplicity of Factors Possibly Causing Amphibian Population
Declines
A number of factors have been proposed as causal agents for amphibian population declines in the
Sierra Nevada. For the mountain yellow-legged frog, these include non-native fish introductions,
pesticides, acidic deposition, nitrate deposition, livestock grazing, UV-B radiation, drought, and disease
(USFWS 2000a). Among these factors, strong evidence has been provided that introduced fishes have
dramatically affected frog populations, and that other environmental factors are also important in
determining site occupancy by the species (Knapp and Matthews 2000). Thus, it is imperative that any
attempt to determine the influence of a specific factor on the distribution of this species be done in light
of the effects of multiple factors, particularly introduced fishes, local environmental factors, and the other
potentially adverse factors identified (Adams 1999). The potential effects of acidic deposition have been
examined in several studies (Bradford et al. 1994a, 1998), two studies of UV-B relative to the mountain
yellow-legged frog are ongoing (Vredenberg, Knapp, and Hansen, unpublished), and examination of
individuals for evidence of disease is included in ongoing surveys for this species in the Sierra.
-------
Section 2
Goals and Objectives
2.1 Goals
The primary goals of this study are to: (1) determine whether chemical contaminants, especially
agricultural pesticides (i.e., insecticides and herbicides) currently used in the SJV, are concentrated in
certain areas and at certain times within the southern Sierra Nevada at high elevation, (2) identify the
topographic and spatial attributes of the landscape that influence contaminant distributions, and (3)
determine whether there is an association between contaminant distributions and unexplained population
extirpations of the mountain yellow-legged frog. Knowledge of contaminant distributions and associated
landscape attributes will increase our understanding of the transport processes that bring contaminants to
the Sierra Nevada. Such knowledge will also provide a basis to direct research or monitoring efforts at
the appropriate times and places where contaminant effects are most likely to occur. Evaluation of the
association between patterns of contaminant distribution and the distribution of the mountain yellow-
legged frog, if any, will provide a test of the hypothesis that contaminants have been a contributing factor
to the recent, dramatic population declines of this amphibian. This animal was formerly abundant
throughout the Sierra Nevada and is currently undergoing review for listing as an endangered species
(USFWS 2000a). Given the magnitude of the declines of this species, and the lack of long-term
longitudinal studies, an evaluation of environmental correlates for changes in the species' distribution
over a large area may be the most effective way to identify causes for its decline (Bridges and Semlitsch
2000; Davidson et al., in press).
A secondary goal of the project is to conduct a preliminary exploratory study of (1) both regional and
long-range transport of persistent organic anthropogenic contaminants to high-elevation watersheds of
the southern Sierra Nevada, and (2) elevational partitioning of semivolatile persistent contaminants.
While the pesticides used in the last 20 years in the U.S. are generally not persistent, several persistent
pesticides are still used in the developing countries of Asia (Li et al. 1996, Donald et al. 1999), and there
is evidence that measurable concentrations of these pesticides may be deposited in western North
America (Blais et al. 2000). In addition, studies in western Canada have shown that persistent chemicals
preferentially condense at higher elevations (Blais et al. 1998), analogous to enhanced condensation at
colder latitudes (Waina and Mackay 1993). Definitive evidence for trans-Pacific transport and
deposition of persistent chemicals from Asia to the Sierra Nevada does not exist. Recent data hints at
elevational partitioning in the Sierra Nevada (Landers et al. 2000), but more information is needed to
conclusively demonstrate this.
-------
2.2 Objectives and Hypotheses
The objectives and hypotheses below refer to selected chemical contaminants in lake water at high
elevation in the southern Sierra Nevada, unless otherwise indicated. Following each hypothesis is a brief
description of the statistical analysis for testing the hypothesis (Zar 1999 and others), or reference to
more extensive discussion in the Statistical Analysis section. Statistical analyses will be done on
contaminants individually and grouped in various ways:
Objective 1 Describe the temporal variation of contaminant concentrations in aquatic media.
Hypotheses are:
HI. 1. Contaminant concentrations in lake water and bed sediment are not constant
over time. (ANOVA with repeated-measures for 6 sites.)
HI .2. Contaminant concentrations in lake water are directly related to
concentrations in bed sediment. (Regression of concentrations in water and
sediment at two times at 6 sites.)
HI.4. Temporal variation of contaminant concentrations in lake water and
deposition fluxes are related to the temporal pattern of chemical application
in the SJV. (Inspection of lake water concentrations and deposition flux
measurements over time versus monthly application totals for five counties.)
Objective 2 Describe the spatial distribution of contaminant concentrations in aquatic media.
Hypothesis is:
H2.1. Contaminant concentrations are not uniformly distributed across the study
area. (Goodness of fit tests; also addressed by hypotheses H3.1, H3.2, and
H3.3.)
Objective 3 Current-use pesticides: Identify the topographic and spatial attributes of the
landscape that influence the distribution of chemicals currently used in the SJV.
Hypotheses are:
H3.1. Concentrations in water and bed sediments are inversely related to the
upslope surface air flowpath distance from the valley, and to elevation.
(Stepwise regression; see Statistical Analysis section.)
H3.2. Cholinesterase activity of tadpoles is inversely related to the upslope surface
air flowpath distance from the SJV, and to elevation. (Statistics same as for
H3.1.)
H3.3. Contaminant concentrations differ among the four major watersheds in the
southern Sierra. (Statistics same as for H3.1.)
H3.4. The composition of contaminant mixtures (i.e., relative concentrations of
contaminants) differs among the four major watersheds and also varies as a
function of upslope flowpath distance and elevation. (Multivariate statistics;
see Statistical Analysis section.)
-------
Objective 4 Pesticides not currently used in SJV: Identify the topographic and spatial attributes of
the landscape that influence the distribution of chemicals not currently used in the
SJV. Hypotheses are:
H4.1. Lake-water concentrations of persistent chemicals not currently used in the
SJV are not correlated with upslope surface air flowpath distance from the
SJV. (Statistics same as for H3.1.)
H4.2. Snow and bed sediment concentrations of persistent chemicals not currently
used in the SJV with vapor pressure above 1 mPa are directly correlated with
elevation. (Statistics same as for H3.1.)
Objective 5 Determine -whether the current distribution of frogs, and recent unexplained
population extirpations of the mountain yellow-legged frog, are associated with the
distribution of contaminants. Hypotheses are:
H5.1. Contaminant concentrations are significant factors in determining site
occupancy by the mountain yellow-legged frog and Pacific treefrog. (See
Statistical Analysis section.)
H5.2. Contaminant concentrations are greatest at historic localities where the
mountain yellow-legged frog has disappeared. (Logistic regression of site
occupancy versus predicted contaminant concentrations.)
-------
Section 3
General Approach
3.1 Overall Study Design
The research involves four components:
1. Contaminant temporal variation study. A study of temporal variation of contaminant
concentrations in aquatic media will be conducted at six lakes beginning in spring 2002, and
continuing through summer 2002. This study will provide an understanding for the magnitude of
contaminant concentrations in southern Sierra lakes, temporal variation of contaminant
concentrations over about half the year, and degree of correspondence between contaminant
levels in different media. Pesticide application in the SJV is highly variable over the year
(Appendix C). Information on the temporal variation of lake-water contaminant concentrations
will be essential to planning the sampling schedule for the survey of contaminant spatial
distributions.
2. Contaminant spatial distribution study. A survey of at least 60 lakes will be conducted to
determine contaminant spatial distributions throughout the study area. This study will be
conducted in summer 2003. We will also sample some sites remote from the study area (i.e., low
elevation southern Sierra, coastal California, far northern Sierra, and eastern Sierra) for
comparison with other studies at this scale.
3. Biological surveys. During 2001 (and possibly 2002) ongoing biological surveys for amphibians,
fish, and habitat characteristics will be completed for all of Sequoia and Kings Canyon National
Parks.
4. Data analysis. Results from the temporal study will be analyzed in 2002-2003; analysis of the
spatial data and evaluation of associations between contaminant distributions and amphibian
distributions will occur in 2003-2004. '
3.2 Study Area and Amphibians
The study area consists of an approximately 130-km long segment of the western slopes of the
southern Sierra Nevada (Figure 1). The specific area of focus is that portion above 2740 m (9000 feet)
elevation, where the vast majority of lakes occur. This study area was selected because it includes the
southernmost, high-elevation lakes in the Sierra, and it encompasses portions of four major watersheds,
i.e., San Joaquin, Kings, Kaweah, and Kern. These watersheds vary considerably in upslope air flowpath
distance from the SJV to lakes, but overlap substantially in linear distance from the SJV to lakes
(Figures 2 and 3). At elevations above 2740 m, bedrock is dominated by igneous intrusive rocks rich in
calcium sodium feldspars or potassium feldspar, with a few areas containing calcium carbonate-rich
-------
sedimentary and metamorphic rocks or volcanic rocks (Melack et al. 1985). Ground cover is largely
rock, soils are thin, and vegetation cover typically consists of sparse subalpine forest and alpine fell
fields (Melack et al. 1985). Most lakes are glacial in origin, oligotrophic, and very low in alkalinity
(Melack et al. 1985). Nearly all lakes have pH between about 6 and 8, with a few lakes with pH<6 due to
natural iron pyrite deposits, and a few lakes with pH>9 due to marine meta-sedimentary sources (Melack
et al. 1985.; Bradford et al. 1998). Land use is low-intensity recreation, and lakes are accessed only by
trail or cross-country hiking. Precipitation occurs primarily during the winter/spring months of
November to March, falling primarily as snow.
Nominal Valley-
Mtn Boundary
_J
Sequoia & Kings
Cyn. Nat. Parks
* Temporal and Spatial
Study Lakes
Spatial Study Lakes
Other Lakes
| | Planning Watersheds
Upslope Distance (km)
Hi ฐ'25
^H 25-50
0Q 50-75
75- 100
100- 125
125- 150
150- 175
175-200
10 0 10_ 20 30 Kilometers
Figure 3. Distribution of lakes and sampling sites in the study area. Lakes represented are those meeting
criteria described in Figure 2 (n=1330). Polygons outlined by thin black lines represent Calwater
"planning watersheds" (see Landscape and Other Metrics section for definition). Green shaded
bands represent upslope flow/path distance from the SJV as in Figure 1.
Four frog spec.es mhabit the study area in lakes and ponds at elevations above 2740 m All four
vdlnw. 6 H'f5 Sฐฐn ^ P070nskofuthe surface water become ice free in early spring. The mountain
Ld JthSง 5nฐnSr 7T f ^ lakeS Wlth depths greater than about 1 '5 m (Bradford 1 989; Knapp
wateM nteWS T'JI^, T^ * IeMt ^ Summers t0 reach metamorphosis, and overwinter in
6 ^*19. Vredenberg, unpublished). Adults remain near open water most of the
t a so
but also
i unpublished). The Pacific treefrog commonly inhabits shallow MdTften ephlmeTal ponds,
iy be found ,n deep lakes (Bradford 1989). Tadpoles reach metamorphosis during one
10
-------
summer. Adults remain at aquatic sites for only a few days or weeks in springtime during breeding. The
Yosemite toad is locally common in water bodies in the northern part of the study area, whereas the
western toad (Bufo boreas) is spottily distributed in the rest of the study area (Karlstrom 1962; Bradford
and Knapp, unpublished). Both of these species tend to inhabit shallow bodies of water, and tadpoles
reach metamorphosis in one summer. Adults generally remain at the aquatic breeding site for only a few
days or weeks at the time of breeding (Karlstrom 1962; Kagarise Sherman 1980).
3.3 Target Media
Lake water will be the primary sampling medium for assessing the temporal and spatial
characteristics of contaminant distributions. This choice is dictated by the large number of lakes to be
sampled in a limited time frame. The field and laboratory logistics of such a study with the resources
available require the sampling medium to be easy to sample reproducibly, and the analytical cleanup and
analysis to be rapid. Lake water meets these criteria better than other potential aquatic media.
Concentrations in water are likely to be lower for some compounds than those in bed sediment and
possibly in aquatic organisms, but previous studies have detected chlorothalonil, chlorpyrifos, diazinon,
endosulfan I, endosulfan n, malathion, and trifluralin in lake water in the study area (LeNoir 1999). The
triazine herbicide, atrazine, was detected hi lake water in Isle Royale Michigan (Thurman and Cromwell
2000), which is much farther removed from areas of heavy use than the current study area (U.S.
Geological Survey 1998). The principal approach for measuring the contaminant concentrations in lake
water will be active sampling, using field filtration and extraction, during discrete sampling events.
Semi-permeable membrane devices (SPMDs) will also be evaluated as a passive method of estimating
lake-water contaminant concentrations integrated over time (Prest et al. 1995). Because SPMDs have not
been used for sampling relatively polar compounds that are the focus of this study, a new type of passive
sampler possibly better suited for these contaminants, the polar organic chemical integrative sampler
(PC-CIS; Alvarez et al. 2000), will also be evaluated.
Snow melt is the dominant source of water for the lakes in the study area. Therefore, it is important
to evaluate the relative significance of snow melt as a source of pesticide loads. Analysis of snow-pack
samples will be conducted during the temporal variation study, and if snow melt appears to be an
important source of contaminants in the lakes, an approach to measure this input will be included in the
spatial distribution study.
Contaminant loads in bed sediment will also be examined. Analysis of lake bed sediments is
complementary to water analysis in assessing the significance of pesticide contamination of lakes.
Though many of the primary target analytes have relatively low Kow values (Appendix B), there is
evidence that some extensively bind to sediment particles. In addition, more hydrophobic organic
contaminants are preferentially adsorbed onto fine particles (Kralik, 1999; Shelton and Capel, 1994).
These chemicals might also have significant impacts on aquatic organisms, and several will be
determined as part of the suite of secondary target analytes (see Target Analytes section).
Total dry deposition and wet deposition fluxes of contaminants will be measured during the
contaminant temporal variation study, if a suitable sampler can be developed (see Sampling and
Measurement Methods section). Total dry deposition includes particle-bound and vapor-phase pesticide
deposited on surfaces by wind currents. Deposition fluxes at the study sites should be directly related to
pesticide use patterns in the SJV.
11
-------
Tadpoles will be analyzed for acetylcholinesterase activity, which can be suppressed by exposure to
pesticides, and has been used as an indicator of exposure to both organochlorine and organophosphate
pesticides in birds and amphibians (Rosenbaum et al. 1988; Sparling et al., in press).
3.4 Target Analytes
The principal criterion for selecting primary target analytes for the contaminant study was substantial
use in the SJV near the study area (specifically, Fresno, Kern, Kings, Madera, and Tulare Counties). It
was assumed that consistent substantial use over the three years 1996-1998 would predict continued
substantial use during the study. Of course, ongoing regulatory actions, such as the recent restrictions on
chlorpyrifos use may affect future use patterns. The 31 proposed primary target chemicals in Table 1
were nearly all used in the SJV at a median annual application rate of at least 5000 kg. The exception is
lindane, which had a median annual use of less than 500 kg. Lindane (y-hexachlorocyclohexane) was
included in the target list because it is a persistent organochlorine pesticide, and its detection limit by the
planned analytical method should be low enough to detect even with relatively low use. Target analytes
in Table 1 represent a range of agricultural chemicals, including organophosphorus pesticides,
organochlorine insecticides and fungicides, herbicides of various types, and three pesticides of
miscellaneous natures. The peak use periods of the 31 chemicals span an entire year.
Other criteria that contributed to the selection of the compounds in Table 1 were (1) appropriate
vapor pressure, (2) reasonable persistence in the water column, and (3) probable detectability using the
proposed sampling and analytical procedures. A detailed description of these other selection criteria is
provided in Appendix B. Principal transformation products of several of the primary target analytes
(e.g., the oxygen analogs of the organophosphates) will also be determined.
In addition to the primary target analytes that represent current-use pesticides in the Central Valley,
the aquatic organisms in the study area are also potentially exposed to parent compounds and derivatives
of persistent pesticides no longer used in the U.S. This exposure could be from compounds persisting in
sediments many years after their use in the U.S. was terminated, and it could be from compounds
deposited after long-range transport from developing countries where they are still used. Other potential
stressors include a host of anthropogenic chemicals that are not agricultural pesticides. Many of these
compounds will be determined in the samples, especially sediments, collected to determine the primary
target analytes. Tentatively, this suite of secondary target analytes includes the pesticides DDT, DDE,
dieldrin, heptachlor, heptachlor epoxide, hexachlorobenzene, a-HCH, and cis- and trans-nonachlor, as
well as selected polycyclic aromatic hydrocarbons (PAHs), and polychlorinated biphenyls (PCBs),
dibenzo-p-dioxins (PCDDs), and dibenzofurans (PCDFs). The final list of secondary target analytes will
depend on their detectability with a reasonable level of additional effort using the sampling and
extraction protocols that will be optimized for the target analytes.
12
-------
Table 1. Tentative list of 31 primary target analytes.3 Transformation products that will also be
determined are not listed.
Compound
alachlor
azinphos methyl
butylate
carbaryl
chlorothalonil
chlorpyrifos
cyanazine
DCPA (chlorthal dimethyl)
diazinon
dicofol
disulfoton
endosulfan (both I and II)
EPTC
ethalfluralin
lindane (y-HCH)
linuron
malathion
methidathion
methyl parathion
metolachlor
napropamide
pebulate
pendimethalin
permethrin
phorate
phosmet
propargite
simazine
trifluralin
tribufos
Class
aniline herbicide
organophosphorus pesticide (OP)
thiocarbamate herbicide
carbamate pesticide
organochlorine (OC) fungicide
OP
triazine herbicide
phthalate herbicide
OP
OC pesticide
OP
OC pesticide
thiocarbamate herbicide
aniline herbicide
OC pesticide
substituted urea herbicide
OP
OP
OP
aniline herbicide
amide herbicide
thiocarbamate herbicide
aniline herbicide
synthetic pyrethroid pesticide
OP
OP
sulfonic acid pesticide
triazine herbicide
aniline herbicide
OP
Annual Use
(kg)
7,259
78,543
20,549
208,877
211,521
650,598
183,568
10,185
145,766
164,026
10,309
54,430
96,144
5,070
463
18,836
65,331
92,307
24,892
22,914
18,372
25,926
131,569
23,574
36,546
135,764
550,508
216,616
232,891
250,774
Season of
Peak Use
spring
summer
spring
summer
spring/summer
summer
summer
spring/summer
winter
summer
spring/summer
summer
spring
spring
spring
fall/spring
summer/spring
winter/summer
spring
spring
winter/spring
spring
spring
summer
spring
summer/spring
summer
winter
spring
fall
Information extracted from State of California (1999) for the period 1996-1998. Annual use data are
active ingredient applied in Fresno, Kem, Kings, Madera, and Tulare Counties in the year of median use
of individual chemical during that three-year period.
13
-------
Section 4
Contaminant Temporal Variation Study
4.1 Study Sites
We selected six lakes from the set of 60 to be included in the contaminant spatial study (Figure 3).
The six were chosen with the expectation that they would reflect a diversity of contaminant conditions,
but not necessarily represent the study area as a whole. Criteria for selection were: (1) location in
Sequoia and Kings Canyon National Parks because helicopter support is available, (2) equal
representation in Kings, Kaweah, and Kern watersheds, (3) proximity to the SJV (i.e., a "near" and a
"far" site in each watershed), and (4) ease of access by foot for at least one site to be used for frequent
sampling and ancillary studies. The six lakes selected range in elevation from 2930 m (9610 feet) to
3643 m (11,950 feet), and range in size from 0.5 to 17.2 ha.
4.2 Study Design
This study will involve sampling from approximately April 2002 through October 2002. The six
lakes will be sampled by two field crews, accessing each site by helicopter. The timing of sampling is
determined largely by the requirement for about 20 hours of water sampling at a site. The study includes
the following sampling elements.
Snow pack: In 2002, the snow column will be sampled once at four of the lakes near the time of
peak snow accumulation and prior to snowmelt (approximately early April).
Monthly scale variability: Lake water (and suspended particulate matter) will be collected at four-
week intervals from the six lakes to follow temporal variation on a monthly scale. These
measurements will be conducted from May through October, 2002. After ice-off, lake water will
be collected from near the outlet. While lakes are ice covered (i.e., May, and possibly through
July for the higher lakes, depending on the snowpack and weather), lake water will be collected
from immediately beneath the ice at a location over deep water. These samples are expected to
represent recent snowmelt because meltwater at this time is typically at 0ฐC and tends to flow
over the wanner lake water (Bradford 1983).
Weekly scale variability: Weekly lake-water samples will be collected at one of the six lakes during
June, August, and October 2002. This will provide a total of 12 week-long intervals to assess
temporal variability on a weekly scale over the ice-free period.
Optional sampling design for weekly scale variability. If method development establishes that a
commercially available programmable, submersible water-sampling device is suitable for the
study (see Field Sampling Approach in Sampling and Measurement Methods section below), it
will be tethered underwater to automatically collect 200-300 L, integrated over each of the 12
weekly intervals.
14
-------
Short-term intensive sampling events: The lake that will be sampled weekly will also be the subject
of three eight-day intensive sampling events. These will be scheduled during June, August, and
October. Eight daily lake-water samples will be collected during each of these sampling periods
to provide integrated concentration measurements for comparison with passive sampling (see
below), and to test our expectation that day-to-day variability of pesticide concentrations is
small.
Sediment sampling: Sediments will be collected in June and October 2002 from all six lakes to
determine loadings of chemicals that tend to partition to this medium.
Passive sampling of lake water: SPMDs and POCISs will be deployed during the short-term
intensive sampling events. Comparison of the sums of the eight daily active sampling
measurements and the passive sampler concentrations will provide an estimate of the sensitivity
and variability of the passive sampling method for the target analytes in a lake-water medium.
This will complement laboratory calibration of SPMDs and POCISs for selected target analytes
that will be performed at the USGS laboratory in Columbia, MO. To assess the performance of
SPMDs and POCISs in measuring lake-to-lake differences in pesticide concentrations integrated
over longer periods, the devices will be deployed at three lakes during each of the monthly
sampling periods from June through October 2002, and the results compared with active
sampling measurements from the monthly and weekly sampling events.
Deposition measurements: If a suitable sampler can be developed for total dry deposition and wet
deposition (see Sampling and Measurement Methods section), they will be installed at three
lakes in early summer, 2002. Deposition samples will be collected every two weeks from mid
July through until October 2002. This will provide three sets of nine measurements at each site.
Tadpole cholinesterase activity: Tadpoles of the Pacific treefrog will be collected in August of 2001,
and July and August of 2002, from two bodies of water near each lake, including the lake itself if
tadpoles are present. If tadpoles of the mountain yellow-legged frog are available in suitable
numbers, specimens of this species will also be taken.
Ancillary environmental data: Data will be collected for a number of environmental parameters
including lake pH, electrical conductivity, dissolved oxygen, temperature, maximum lake depth,
and precipitation. See Sampling and Measurement Methods section for these and other
parameters.
15
-------
Section 5
Contaminant Spatial Distribution Survey
5.1 Study Sites
We selected lakes for sampling in a stratified random manner designed to test the hypotheses listed
above, and to provide a representative sample of habitat for the mountain yellow-legged frog. We
selected 60 lakes for sampling in the spatial survey in the following manner:
1. Elevation > 2740 m (-90001) and < 3660 m (-12,000'). The minimum elevation is set because
relatively few lakes occur below 2740 m. The maximum elevation represents the approximate
upper elevation limit for the mountain yellow-legged frog (Jennings and Hayes 1994).
2. Lake area > 0.5 ha. Lakes of this minimum size are likely to be of sufficient depth (i.e., > 1.5 m)
to comprise potential habitat for the mountain yellow-legged frog, and they are accurately
represented on USGS 7.5' maps.
3. Twelve lakes were selected from the Kaweah watershed, and 16 from each of the other three
watersheds. The Kaweah watershed is under-represented because its lakes vary relatively little
in upslope and linear distance from the STV, and its lakes are distributed over a much smaller
area than the other watersheds (Figures 2 and 3).
4. Within each watershed, lakes were stratified by upslope air flowpath distance from the SJV and
elevation (Figure 3). For both flowpath distance and elevation, the range in values (max-min)
was divided into 4 equal-sized intervals (except we used only three distance categories for the
Kaweah watershed), and one lake was randomly selected from each distance/elevation category
per watershed. One lake was excepted from this process, and was included because of its
accessibility and history in previous studies.
5. A further restriction was placed upon lake selection in order to maximize the number of Calwater
"planning watershed" units represented, thus spreading the lakes out spatially within each
watershed (Figure 3). That is, if a lake being selected was in a Calwater unit that was already
represented among selected lakes, it was excluded from the selection process unless there were
no alternatives. The order of selection of distance/elevation categories was randomized.
6. Finally, we rejected a selected lake if it was within 1.0 km of an already-selected lake, if it
drained into or from an already-selected lake, or if the lake was dammed.
16
-------
Of the resulting 60 lakes, 36 are within Sequoia and Kings Canyon National Parks and 24 are in the
three adjacent national forests (Figure 3). All lie within designated wilderness areas. The lakes range in
elevation from 2744 m (9000 feet) to 3643 m (11,950 feet), and range in size from 0.5 to 32.0 ha.
5.2 Study Design
Results of the temporal variation study will be used to finalize the design of the contaminant spatial
distribution survey. Some spatial variation in contaminant levels must be evident from the temporal
variation study to warrant proceeding with the spatial distribution survey. Assuming this is the case, we
will choose a sampling period when the temporal variation study indicates contaminant levels in lake
water are likely to be measurable and relatively stable, presumably after ice-off. We expect to conduct
the spatial distribution study in summer, 2003. If the snow-pack samples collected in the temporal
variation study indicate that snow melt is an important source of pesticide contamination, the spatial
distribution of loadings from snow melt will be incorporated in this phase of the project. The approach
for evaluating loading from snow melt (e.g., the number of sites to be included, and whether to measure
contaminants in snow pack or intensively monitor lake water during spring melt) would be decided in
2002, with sampling occurring in 2003.
Lake-water sampling will be by the active sampling (i.e., field filtration and extraction) method,
unless the evaluation of SPMDs and POCISs during the temporal variation study indicates that passive
sampling can be reliably substituted. Each site will be sampled over approximately a 20-hour period for
water and Pacific treefrog tadpoles as described for the temporal study. Sediment will be included in the
sampling if the temporal variation study indicates concentrations of some contaminants in sediment are
higher or more stable than concentrations in lake water. Sampling will be done by two crews of two
individuals each, accessing each site by helicopter. Because the survey of all 60 lakes (plus some
duplicates) will take place over about 8 weeks, we will sample the lakes in blocks of 8 (i.e., a randomly
selected "near" and "far" lake relative to the SJV from each of the 4 watersheds) over a 5-day period.
We may also add additional sites if our cost estimates become more optimistic based on results of the
temporal variation study. We may also incorporate snow sampling at some sites if warranted based on
the results of the temporal variation study.
We will also sample a few sites remote from the study area (specifically, low elevation southern
Sierra, coastal California, far northern Sierra, and eastern Sierra) for comparison with previous and
ongoing studies at this scale. These sites will be selected to coordinate with the ongoing study by USGS-
Biological Resources Division of pesticides and amphibians throughout central California and the Sierra
Nevada. The present study is complementary to the USGS study by focusing more intensively on one
portion of the Sierra and one amphibian species. In particular, our sampling will be more intensive
temporally and spatially than the USGS study, and at higher elevation. Moreover, multiple factors will
be included in our analysis of association between contaminants and amphibian distribution.
17
-------
Section 6
Biological Surveys
Hypotheses concerning frog distributions will be addressed for the two widespread species in the
study area: the mountain yellow-legged frog and Pacific treefrog. Several factors are known to be
important determinants for the occurrence of these species. Consequently, such factors must be included
in the analyses in order to detect relationships between frog occurrence and contaminant variables. Chief
among these is the presence/absence of introduced fishes and lake depth (Bradford 1989; Knapp and
Matthews 2000).
Analysis of amphibian distributions will be done for Sequoia and Kings Canyon National Parks only
(Figures 1 and 3). This is because fish stocking has been much less intensive in the parks than in the
neighboring national forests, and consequently fish density is much lower (Knapp and Matthews 2000).
Thus, analysis of frog distributions in the parks affords the best opportunity to detect relationships
between the distributions of frogs and contaminants.
In 1997,1059 water bodies were surveyed in a consistent manner for frog populations, fish
presence/absence, and habitat characteristics (Knapp and Matthews 2000). In 2000, further surveys were
conducted in the same manner for over 900 water bodies in the parks under the supervision of Roland
Knapp. These surveys also include examination of individuals for evidence of chytrid fungus infection,
which has been implicated as a factor in the amphibian declines in the Sierra Nevada and elsewhere
(Carey et al. 1999). In 2001, surveys will continue in unsurveyed areas, and a portion of the areas
previously surveyed in 1997 will be re-surveyed. By the end of summer of 2001 (or possibly 2002), all
of the 3200 mapped water bodies in the parks will have been surveyed.
18
-------
Section 7
Sampling and Measurement Methods
7.1 Methods for Active Field Sampling and Determination of Contaminants
in Lake Water
7.1.1 Data Quality Objectives
The lake water contaminant concentrations found by LeNoir et al. (1999) at two sub-alpine lakes
(3,231 and 3,322 m elevation) can be used to estimate the detection limits needed to reliably determine a
substantial number of the target analytes. Contaminant levels in the lakes were below detection limits for
four of eight analytes in that study, and the measurable concentrations were generally less than 1 ng/L.
The chemicals measured hi that study (chlorothalonil, chlorpyrifos and its oxon, diazinon, endosulfan I
and n, malathion, and trifluralin) are more widely used in the adjacent Central Valley than many of the
target analytes of this project (Table 1). To detect differences hi contaminant levels across space and
time, detection limits should be at least a factor of 50 below the measured concentrations. Therefore,
method detection limits below 5 pg/L will be sought for most of the target analytes. This will require
collection of large volumes of lake water, gas chromatography/mass spectrometry (GC/MS) analysis of a
substantial fraction of the extracted analytes, low instrumental detection limits, and low method blanks.
Because concentrations of some of the secondary analytes (i.e., those not currently used in the SJV) are
expected to be even lower than those of the target analytes (Donald et al. 1999), method detection limits
on the order of 50 fg/L will be sought for these. Instrument detection limits for these compounds in the
negative chemical ionization (NCI) mode should be substantially lower than those of most of the target
compounds in the electron impact (El) mode, facilitating lower method detection limits if blank levels
can be minimized.
The sampling and analysis methods must also be reproducible. An overall recovery precision (RSD)
of ^30% will be the goal of the study. Overall recovery precision will be affected by variations in lake
chemistry and between-sampling-team variance. Between-sampling-team variance will be assessed in a
field trial before the temporal variation study begins. Surrogate recoveries will be used to estimate the
overall recovery precision.
7.1.2 General Sampling and Analysis Approach
The sampling and analysis approach for the target analytes in lake water can be summarized as field
filtering and extraction of 200-300 L of lake water onto a glass fiber filter and appropriate extraction
resin, extraction of the filter and resin with organic solvent, appropriate extract cleanup and volume
reduction, and analysis by GC/MS in the El and NCI modes, using selective ion monitoring (SIM). The
19
-------
methods of LeNoir et al. (1999), Shelton and Capel (1994), and Jarman (Walter Jarman, University of
Utah, unpublished) will be used as starting points. Extensive method development and testing will be
conducted prior to April 2002 to finalize the approach. Method development will focus on field
sampling (water extraction), sample processing (back extraction of resin), cleanup, volume reduction, and
analysis (GC/MS methods). Our first priority will be to have a working method in time for pilot field
work in late fall 2001. This will allow us to evaluate the entirety of field and laboratory protocols and
associated logistics and make modifications in time for the 2002 sampling season. It may necessitate
using an existing analytical method for a limited number of pesticides (e.g., those measured by Lenoir et
al. [1999]) for the 2001 effort and introducing improved methods for the entire suite of primary and
secondary target analytes in 2002.
7.1.3 Method Development for GC/MS Analysis
Adaptation of the methods referenced in Table B. 1 (Appendix B) will be used as a starting point for
two composite methods, one EI(SDvl) for all the analytes and one NCI(SEvI) for the chlorinated analytes
that are amenable to that ionization method. Emphasis will be given to high-volume injection approaches
(Engewald et al. 1999), where 100 \iL or more of sample can be analyzed. This will allow analysis of a
large portion of the total extract (30% or more) without complicated solvent evaporation schemes and
micro-sample handling, both of which introduce additional analytical uncertainty. Two qualifying ions,
in addition to the major ion for quantification, will be used for compound identification. In addition to
the parent compounds, major environmental transformation products, such as the oxygen analogs of the
phosphorothioate pesticides, will be measured.
7.1.4 Method Development for Sampling and Sample Processing
These two aspects of the methodology will be developed concurrently. Throughout, contamination
will be minimized. Whenever possible, materials contacting water sample, resin, or extracts will be
cleaned by baking at 550ฐC. Otherwise, solvent rinsing procedures will be developed.
The first decision to be made is the type of extraction resin to be used. XAD-2 (Datta et al. 1998),
and CIS (LeNoir et al. 1999, Thurman and Cromwell 2000) have been used to extract organic
contaminants from water, although XAD-4 can also be used for water analysis (Rohm and Haas 1999)
and it has been used to collect some of the target contaminants from air (Zabik and Seiber 1993, Aston
and Seiber 1997, LeNoir et al. 1999). Recently, a mixed styrene-divinylbenzene/methylrnethacrylate
resin has provided good recovery for polar solutes from water (Osemwengie, unpublished). Each of
these resins will be evaluated for analyte recoveries, maximum practical sampling rate, and analyte
breakthrough volume (300 L sample volume being the goal).
Once the optimal resin and water extraction conditions have been determined, the resin cleanup and
back extraction (removing analytes to an organic solvent for GC/MS) methods will be optimized. If
acceptable blanks are not attainable with reasonable cleanup effort, the resin selection process will
resume. Resin drying will be performed with a purifed nitrogen stream. Glass fiber filters containing
suspended particulate matter will be batch extracted with solvents (e.g., Soxhlet). In-column elution will
be developed and evaluated for the resin. If performance is inadequate, batch extraction (e.g., Soxhlet)
will be pursued. Extraction may need to be effected with chlorinated solvents (LeNoir et al. 1999).
Although methylene chloride has been used as a solvent for the determination of chlorinated pesticides
by NCI GC/MS with large-volume sample injection (Staniewski et al. 1993), it may be more practical to
20
-------
perform solvent exchange prior to analysis. Separation on floracil and/or silica will be used to isolate the
various primary and secondary target compound classes. With the large-volume injection method,
extract volumes will only have to be reduced to about 200-300 uL. This will be effected by either
Kuderna Danish or TurboVap (Zymark Corporation, Hopkinton, MA) evaporation.
7.1.5 Field Sampling Approach
Once water extraction and lab processing procedures are successfully applied on spiked reagent
water in the laboratory, a series of field experiments will be performed to develop and validate the field
extraction methods and the overall sampling/processing/analysis method. The following describes the
initial approach for the field extraction methods:
Water samples will be collected using a field-portable extraction system capable of extracting at least
200 L of water in less than 20 hours. Initial method development will be with the Infiltrex 100
instrument (Axys Group, Sidney, British Columbia). This instrument comprises a glass-fiber (45 urn)
filter to collect suspended particulate matter, an extraction column containing approximately 50-g resin, a
positive-displacement pump to draw the water sample through the filter and extraction column, a flow-
measuring sensor, a microprocessor for instrument control, and internal power through two 6-V alkaline
batteries (an external battery for additional power will be used to sample the required volume of water).
The pump follows the extraction column, and all sample-contacting components upstream of the pump
are Teflon to minimize contamination and analyte sorption loss.
Before ice-off a hole will be drilled in the ice with an ice auger at a location over relatively deep
water. Before use, the sampling apparatus will be thoroughly rinsed with lake water before the glass
fiber filter and resin column are installed. The sampling apparatus will be placed adjacent to the hole,
and the sample will be drawn through tubing described below from a point 5-10 cm below the ice level
and about 1 m lateral to the hole.
After ice-off, the sampling apparatus will be deployed on the shore of each lake near the outlet. A
sampling boom constructed of 3/4" aluminum channel, approximately 9 m in length, supported by high-
density polyethylene floats will be used to deploy PTFE Teflon tubing (3/8" I.D.) from the sampling
device to a point approximately 5-7 m from shore, and 20 cm depth. The depth of the lake at the
sampling position will be determined to be at least 1 m before sampling.
After about 18 hours of sampling (300 L water sample), the resin column and glass fiber filter will be
removed, wrapped in aluminum and sealed in glass jars. The rest of the sampling apparatus will be
cleaned with detergent and water and a small amount of deionized water prior to transport from the site.
Resin and filter will be cooled to 4ฐC within 2 hours and transported back to the Environmental Sciences
Division (BSD) laboratory within 3 days of collection.
An alternate sampling procedure will be followed for the weekly scale variability sampling if the
Infiltrex 100 is used in the programmed mode. The Infiltrex will be programmed to collect 42 samples,
one every four hours, during the week. Total sample volume will be determined during method
development. Before initiating programmed sampling, surrogate compounds will be injected on-site
while sampling a small volume of lake water. The sampling program will be activated (with a delay to
allow site disturbance to subside) and tethered 30 cm below the surface at the sampling position with a
21
-------
float and anchor. The float will be below water surface to minimize the chance of disturbance during
sampling.
7.2 Passive Sampling Methods
Two SPMD and two POCIS devices will be deployed at a depth of 50 cm near the lake outlet. They
will be tethered to the lake bottom with a screw anchor and steel cable.
7.3 Contaminants in Snow
A pit will be dug with a snow shovel to the base of the snow pack. Snow will be removed from the
pit wall with a cleaned aluminum or stainless-steel shovel to expose a clean surface; then snow sample
will be collected from four equal-length segments spanning the entire depth of snow pack.
Approximately 40 kg of snow will be collected from each segment. A duplicate sample will be collected
at one of the sites. The general sample-processing approach used in Canadian studies (Blais et al. 1998)
will be used Snow from each segment will be placed in a separate pre-rinsed aluminum can, sealed, and
transported back to the laboratory. Snow will be melted slowly in the laboratory, then extracted,
processed, and analyzed the same as the lake water.
7.4 Contaminants in Bed Sediment
Bed sediment will be collected from the deepest portion of the lake from a float tube. The sampling
device will be a gravity corer similar to those used by Hongve (1972) and Rose et al. (2001). The corer
will be dropped or pushed into the sediment depending on the depth of the lake, and retrieved by a
connected line. A plunger will be used to extrude the sediment, and 8-12 0.5-cm slices will be collected,
to a maximum depth of 4 to 6 cm. If necessary, replicate cores will be taken to collect a sample of at
least 20 g in each slice. At some lakes, a separate core will be taken for 210Pb dating (Turner 1998). All
samples will be stored in contaminant-free Teflon jars, protected from light, cooled to 4ฐC within 2
hours, and transported to the BSD laboratory within 3 days of collection. Samples will be extracted,
processed, and analyzed using published approaches (Muir et al.1995, Okumura and Nishikawa 1995,
Pearson et al. 1997, Fernandez et al. 1999, Rose et al. 2001) as starting points.
7.5 Contaminants in Deposition
Development of a suitable sampling system will be pursued in 2001. We expect to collaborate in this
work with experts in deposition monitoring. We have discussed possible approaches with Dr. Thomas
Holsen of the Civil and Environmental Engineering Department of Clarkson University. Design
considerations will include ability to sample unattended, stabilization of at least a limited suite of
analytes for two-week periods, operation on small batteries (or without power), and a relatively small
footprint and unobtrusive appearance. Optimally, a sampler for both total dry deposition and wet
deposition will be developed. However, if such a system proves unfeasible, a simple dry-deposition
sampler can provide useful data. For the latter, either greased mylar strips (Franz et al. 1998, Odabasi et
al. 1999) mounted on an aluminum sheet, or an ungreased collector (LeNoir et al. 1999) could be
deployed under a cover to protect the sampler from rain (Perm and Holtberg 1999). The sampling system
will be evaluated in the Las Vegas Valley prior to deployment at the study sites. Samplers will be
22
-------
deployed at three contaminant temporal variation study sites in 2002. Deposition samples will be placed
in Teflon jars, cooled to 4ฐC, and transported to the BSD laboratory within 3 days of collection.
Extraction and cleanup procedures will depend on the collection medium, but will probably be based on
published methods (Franz et al. 1998, Odabasi et al. 1999, LeNoir et al. 1999).
7.6 Tadpole Cholinesterase Activity
It is unlikely that any amphibians will inhabit more than two or three of the six lakes, largely because
of the ubiquity offish in the larger lakes. However, we anticipate being able to locate other water bodies
near each of the six sample sites that will contain tadpoles of the Pacific treefrog and, in a few cases,
tadpoles and adults of the mountain yellow-legged frog. We will collect whole tadpoles of the Pacific
treefrog near all six sites at two times, July and August. Sample size will be 5-10 individuals at each site
(one individual per cryovial). We will collect individuals from two ponds if possible because of family
level variation in toxic effects (Bridges and Semlitsch 2000). Collection will be done by dip net, and
animals will be killed by freezing in liquid nitrogen, carried in a 5-liter dewar. If tadpoles of the
mountain yellow-legged frog are abundant (i.e., > 40 individuals in their second or later summer), we
will also collect specimens in the same manner as for the treefrog. We estimate that no more than 3
individuals (second year or older) of this species would be collected per site. We also anticipate Pacific
treefrog tadpoles to occur near nearly all of the 60 lakes in the spatial survey. Assuming the spatial
survey takes place during mid summer, when tadpoles are available, we will collect individuals during
the spatial survey in the manner described above. To reduce the possibility of transmitting amphibian
pathogens between sites, particularly chytrid fungus, all equipment used in collecting amphibian
specimens or contacting the lake benthos or vegetation (e.g, nets, tevas, waders, sediment corer) will be
thoroughly dried between sites or decontaminated with a solution of bleach or the veterinary disinfectant,
Quat-128.
Tissue samples will be sent to the Dr. Don Sparling at Patuxent Wildlife Research Center, Laurel,
MD, for analysis of acetylcholinesterase activity according to established methods (Ellman et al. 1961),
and in the same manner as current USGS projects. Samples will be temporarily stored at -80ฐC.
Transport will be in containers with liquid nitrogen or dry ice.
7.7 Ancillary On-site Environmental Data
pH will be measured with a pH meter and quick-responding electrode suitable for waters with
extremely low ionic strength. Electrical conductivity will be measured with a portable meter. Both pH
and conductivity will be measured in the field, using standards to calibrate before and after each
measurement. Water temperature will be measured with a calibrated liquid-filled maximum-minimum
thermometer suspended in the water column near the water sampling intake. For the six lakes in the
temporal study, lake depth will be taken at 9 approximately evenly spaced points, and at the point of
maximum depth, once with a plumb line from a float tube. Water level will be monitored monthly for
these lakes by measuring the water level relative to a plastic stake imbedded in the lake bottom. Prior to
ice-off, dissolved oxygen and temperature profiles for the water column will be measured using a Yellow
Springs Instruments oxygen meter. Precipitation will be measured continuously for the six lakes in the
temporal study using a battery-powered rain gage and data logger placed near each lake. For the 60 lakes
in the spatial survey, maximum lake depth will be measured during the biological survey. Weather
23
-------
records for both the temporal study and spatial survey will be obtained from Lodgepole and Huntingdon
Lake, both at approximately 2150 m (7,000 feet) elevation.
7.8 Landscape Metrics and Other Variables
The nominal boundary between the SJV and Sierra Nevada was defined as the approximate line
where the mountain-valley slope changes substantially. In the Kaweah River area, this boundary
corresponds approximately with the edge of the air mass that moves up slope each morning in summer
(Shair 1995). This boundary was delineated from raised relief and contour maps as a general NW-SE
line following certain contour levels, but the line was smoothed to eliminate prominent lateral deviations.
Contour levels comprising the basis for this delineation are the 150-m contour for slopes near the San
Joaquin, Kings, and Kaweah Rivers, increasing to 180 m near the Kern River.
Upslope air flowpath distance from the SJV is approximated by assuming that the air flowpath is the
opposite of the downslope water flowpath. The latter is calculated from a 100-m digital elevation model
(DEM) and the Grid module of Arc/Info (version 7; ESRI, Redlands, CA; Watershed, Flowdirection,
Flowaccumulation, and Sink commands) and the Flowlength commands in ArcView (version 3.2, ESRI,
Redlands, CA). For computation, the origin for each watershed was the point where the respective river
crosses the nominal boundary between the SJV and the Sierra Nevada (Figures 1 and 3).
Calwater "planning watersheds," which range in size from about 1200 to 4000 ha, are obtained from
the California Watershed Map (CALWATER version 2.2; California Resources Agency, Sacramento).
Lake surface area is obtained from digital line graphs (USGS) derived from USGS 7.5' topographic maps.
Elevation is also taken from these maps. Lake volume will be computed for the 6 lakes in the temporal
study from lake surface area and bathymetry using a float tube and plumb line. Volume of each lake in
the spatial survey will be estimated assuming that lake shape is an inverted conical polygon, i.e.,
estimated volume = lake surface area * maximum lake depth/3. Watershed area for each lake will be
derived from 30-m DEM using ArcView. Pesticide application data will be obtained for Madera, Fresno,
Kings, Tulare, and Kern Counties on a monthly basis from the California Department of Pesticide
Regulation. Data for pesticide use are available at the township spatial scale.
7.9 Field Logistics and Training
We plan to reach sites using a helicopter on contract to the Sequoia and Kings Canyon National
Parks, based at the Park Headquarters at Ash Mountain. Justification for helicopter use is provided
separately. During the monthly sampling in the contaminant temporal study, and during the contaminant
distribution survey, two crews of two individuals will be transported from one site to another each day,
over a period of 4 to 5 days. A single crew of two will conduct the weekly and short-term intensive
sampling events. For the latter, an additional helicopter trip will transport the supplies needed for the
extended stay. Crews will be prepared to be picked up within a fairly wide time window (e.g., 3 hours),
and remain in place or hike out as necessary if the helicopter is co-opted for emergencies. Except during
the short-term intensive sampling events, field samples of extracts from lake water, sediment,
SPMD/POCISs, dry deposition, and tadpoles will be transported from the field site by helicopter each
day to Park Headquarters. An individual will receive the samples there and place them in a refrigerator
(or liquid nitrogen for tadpole samples) until transport to the ESD laboratory at Las Vegas. Field
samples collected during the short-term intensive sampling events will be held at the sampling site in a
24
-------
cooler at 4ฐC at the sampling site until the end of the sampling event. Individuals participating in field
sampling will receive helicopter training in coordination with the Sequoia and Kings Canyon National
Parks, and safety training through EPA. Field crews will be composed of individuals from EPA
identified below, and National Park Service employees or cooperators. All individuals participating in
the field sampling will undergo training to ensure standard operating procedures are followed.
25
-------
Section 8
Data Management and Analyses
8.1 Data Management
Field data will be collected on data sheets, and entered into a SAS (SAS Institute Inc., Gary, NC)
database in our laboratory. For each sample collected, sampling, processing, and analysis log sheets and
final analytical data sheets will be maintained in a single folder. Raw analytical data will be maintained
on the GC/MS data system. Final data and associated metadata will be maintained on EPA's National
Exposure Research Laboratory Database for Ecochemistry Studies (NDES), an Oracleฎ-based database
linked to the EPA Environmental Information Management System. Reports from NDES will be
generated to directly enter into SAS for statistical analysis. Data and metadata on NDES will also be
available outside EPA via the internet.
8.2 Statistical Analyses
Statistical analyses will be done using SAS except where stated otherwise. Several hypotheses will
be tested using common techniques listed in Goals and Objectives. For hypotheses concerning
contaminant concentrations as a function of landscape features (H3.1 H3.3, H4.1, H4.2), stepwise
regression (n=60) will be used. The dependent variable will be contaminant concentration (for individual
analytes or groups of analytes) and independent variables will be upslope air flowpath distance from the
SJV, elevation, watershed designation, maximum lake depth, estimated lake volume, and lake watershed
area. We will also test whether linear distance to the SJV is a better predictor of contaminant
concentration than upslope air flowpath length. Hypothesis H3.2 (cholinesterase activity) will be tested
in a similar fashion. To detect meaningful correspondence between the composition of contaminant
mixtures and environmental variables (H3.4), we will use multivariate analyses (e.g., canonical
correspondence and redundancy analyses using CANOCO 4; ter Braak and Smilauer 1998).
We will develop a model predicting contaminant concentrations for the study area based on results
from the above multivariate analyses, or based on spatial interpolation models (e.g., Kriging). Validation
of the model will be evaluated using jackknife or cross-validation procedures (Journel and Huijbregts
1978; Sheskin 2000).
Possible associations between contaminant concentrations and the distribution of frogs (H4.1) will be
examined at three spatial scales. (1) At the scale of the major river watersheds (n=4), we will evaluate
associations by inspection of plots of % of lakes occupied by the two frog species and plots of either the
means of measured contaminant concentrations in the watersheds or the means of contaminant
concentrations predicted by the above model. (2) At the scale of Calwater planning watersheds (n~55),
stepwise regression will be used. The dependent variable will be % occupancy of lakes by the frog
species, and the independent variables will be mean predicted contaminant concentration, % lake
26
-------
occupancy by fish, and means for several other habitat and isolation variables known or suspected to be
important in determining site occupancy (Knapp and Matthews 2000). Some of these independent
variables reflect other hypotheses for amphibian population declines, e.g., pH and EC may reflect
vulnerability to acidification (Bradford et al. 1994a), and elevation may reflect vulnerability to UV-B and
climate change (Davidson et al., in press). (3) At the scale of individual lakes (n ~ 3200), we will use
Generalized Additive Models using the GAM function in SPlus to fit additive models (Cleveland and
Devlin 1988; Hastie and Tibshirani 1991). GAM will be used rather than linear models because GAM
relaxes the assumption that the relationships between the dependent and independent variables are linear
(Cleveland and Devlin 1988; Hastie and Tibshirani 1991). The dependent variable will be frog
presence/absence and/or abundance, and independent variables will be predicted contaminant
concentrations, fish presence/absence, and several other habitat and isolation variables known or
suspected to be important in determining site occupancy as described above (Knapp and Matthews 2000).
Because the sample size is large, we can include concentrations for a number of contaminants to test for
combinations that most influence frog distribution. We will test for spatial autocorrelation of variables
using semivariograms (Englund and Sparks 1991), and adjust for autocorrelation by eliminating sites
within the zone of dependency of other sites (i.e., thinning of data; Davis 1973, Thompson 1992) or
adjusting degrees of freedom (Pinel-Alloul et al. 1999).
27
-------
Section 9
Permits and Approvals
9.1 Permits and Permissions
All lakes selected for sampling occur in wilderness areas managed by either the National Park
Service (Sequoia and Kings Canyon National Parks) or USDA National Forest Service (Sierra, Sequoia,
and Inyo National Forests). Research approval permits and permissions will be obtained from these
agencies prior to commencement of field activities. Collecting permits for amphibian specimens will be
obtained from the California Department of Fish and Game and the National Park Service.
9.2 Justification for Helicopter Support
Permission to use helicopter support in wilderness areas will be sought prior to the 2001 field season
for National Park lands, and prior to the 2002 field season for National Forest lands. Helicopters will be
used to transport field crew and equipment among sample sites, and bring samples out from the
backcountry, as described in the Contaminant Temporal Study and Contaminant Spatial Survey.
Helicopter support is needed because of the timing and sample-handling requirements of the study. To
minimize the influence of temporal variation in contaminant concentrations, sampling must be done
within a short time frame (e.g., six lakes in three days in the contaminant temporal variation study). To
ensure sample integrity, samples will be extracted at the BSD laboratory within seven days of collection,
reflecting the holding times of the target analytes (Zaugg et al. 1995) and samples must be cooled (4 ฐC)
within two hours of collection. None of these criteria can be met using over-land access.
28
-------
Section 10
Quality Assurance
A detailed Quality Assurance Project Plan (QAPP) will be developed and approved by the EPA QA
officer at the Las Vegas laboratory prior .to initiation of field work. Some elements that will be included
in this plan have been described above in individual sections. The QAPP will require standard operating
procedures for all activities. All individuals participating in sampling will receive training to ensure
consistency of sampling.
29
-------
Section 11
Schedule
Year#
(From - To)
Yearl
(11/2000-10/2001)
Year 2
(11/2001 -10/2002)
Year3
(11/2002-10/2003)
Description
Project planning.
Methods development.
Field testing, final SOPs compiled, field training.
Biological surveys continued and possibly completed.
Pilot study for contaminant temporal variation study (Seq. /Kings
Cyn. Nat. Parks [SEKI]). (See Table 2 for details of the
schedule.)
Contaminant temporal variation study (Seq./Kings Cyn. Nat.
Parks [SEKI]).
Preliminary analysis of contaminant temporal variation study.1
Contaminant spatial distribution survey (SEKI and national
forests).
Data analysis of contaminant temporal study.
Data analysis of contaminant spatial distributions relative to
environmental factors and amphibian distributions.
Manuscript preparation.
Date(s)
11-12/00
12/00-7/01
8/01
6-10/01
8-10/01
4-10/02
11-12/02
6-10/03
Preliminary analysis focuses on appropriate time frame for spatial study.
30
-------
Table 2. Schedule for contaminant temporal variation study, 2002.
Sampling Frequency
D = Daily
W = Weekly
M = Monthly
Numerals indicate number of
lakes sampled for each event
Sample Description
Snow
Water
Passive samplers
Sediments
Deposition1
Tadpole cholinesterase activity2
April
D
W
M
4
May June
D
W
M
6
D
1
W
1
1
M
6
3
6
3
July
D
W
3
M
6
3
3
6
August
D
1
W
1
1
3
M
6
3
3
6
Sept.
D
W
3
M
6
3
3
Dctober
D
1
W
1
1
3
M
6
3
6
3
Deposition will be collected every two weeks.
" Tadpole sampling will also occur in August 2001.
31
-------
Section 12
Personnel and Responsibilities
Personnel and their general responsibilities are provided in Table 3. See Appendix D for resumes.
Table 3. Personnel and responsibilities.
Name
David Bradford, Ph.D.
Ed Heithmar, Ph.D.
Chad Cross, Ph.D.
Elizabeth Gentry
Roland Knapp, Ph.D.
Georges-Marie Momplaisir, Ph.D.
Maliha Nash, Ph.D.
Lee Riddick
Charlita Rosal
Nita Tallent-Halsell
Katrina Varner
Affiliation
2
1
2
1,3
4
1
2
1
1
2
1
Primary Responsibilities
Co-Principal Investigator (biology); field sampling
Co-Principal Investigator (chemistry); field
sampling, data management
Statistical design and analysis
Methods for field sampling and chemical analysis
Biological surveys and related data analysis
Analytical methods development; field sampling,
data management
Statistical design and analysis
Analytical methods development; sample analysis
Sediment sampling methods
Project coordinator; logistics; field sampling
Methods development for water sampling and
processing; field sampling
U.S. EPA, National Exposure Research Laboratory, Environmental Sciences Division,
Environmental Chemistry Branch, Las Vegas, NV
U.S. EPA, National Exposure Research Laboratory, Environmental Sciences Division,
Landscape Ecology Branch, Las Vegas, NV
Tulane University, School of Public Health, New Orleans, LA
University of California, Sierra Nevada Aquatic Research Laboratory, Mammoth Lakes, CA
32
-------
Section 13
Facilities, Equipment, and Other Resources
The Environmental Sciences Division of the National Exposure Research Laboratory at Las Vegas
has extensive facilities for chemical analyses, statistical analyses, and field logistics. The analytical
chemistry facilities and equipment available in the Environmental Chemistry Branch are described in
Appendix E. The Laboratory has obtained a GC/MS to be dedicated to this project. We have a
laboratory that can be used as a field staging area, vehicles, and all software for statistical analysis,
spatial analysis, and data base management described above. An Infiltrex 100 water sampling device is
currently on loan for method development from the Axys Group, Sidney, British Columbia. Additional
sampling devices for sampling water and other media will be purchased. The National Park Service
(NFS) will provide laboratory space at the Southern Sierra Research Center at Ash Mountain to process
samples received from the field. NFS will also provide helicopter support on a cost reimbursable basis.
Funding for the ongoing biological survey has been provided primarily by NFS and the joint EPA/NFS
Park Research and Intensive Monitoring of Ecosystems Network (PRIMENet).
33
-------
Section 14
Anticipated Products
1. Journal article on temporal variation in pesticide levels in lakes in the southern Sierra Nevada.
2. Journal article on comparison of active sampling methods for current-use pesticides in lake
water.
3. Journal article on comparison of active sampling methods, SPMDs, and POCISs for current-use
pesticides in lake water.
4. Journal article on pesticide distributions and associated environmental variables in the southern
Sierra Nevada.
5. Journal article evaluating the role of pesticides in determining the current distribution and
population changes of the Mountain Yellow-legged Frog and Pacific treefrog in southern Sierra
Nevada.
34
-------
Literature Cited
Adams, M. 1999. Correlated factors in amphibian decline: exotic species and habitat change in western
Washington. Journal of Wildlife Management 63: 1162-1171.
Alvarez, D.A., J.N. Huckins, J.D. Petty, W.L. Cranor, R.W. Gale, C. Rostad, E. Furlong, T. Leiker, S.
Werner, and S.E. Manahan. 2000. Status of the development and testing of a holistic passive
sampling approach for organic contaminants in water. 21st Annual Meeting of the Society for
Environmental Chemistry and Toxicology, November 12-16, 2000, Nashville, TN.
Aston, L.S., and J.N. Seiber. 1997. Fate of summertime airborne organophosphate pesticide residues in
the Sierra Nevada mountains. Journal of Environmental Quality 26: 1483-1492.
Blais, J.M., D.W. Schindler, D.C.G. Muir, L.E. Kimpe, D.B. Donald, and B. Rosenberg. 1998.
Accumulation of persistent organochlorine compounds in mountains of western Canada. Nature 395:
585-588.
Blais, J.M., D.W. Schindler, and D.C.G. Muir. 2000. Accumulation of persistent organic pollutants at
high altitudes in the Canadian rocky mountains. First International Conference on Trans-Pacific
Transport of Atmospheric Contaminants, July 27-29, 2000, Seattle, WA.
Blanchard, C.L., E.L. Carr, J.F. Collins, T.B. Smith, D.E. Lehrman, and H.M. Michaels. 1999. Spatial
representativeness and scales of transport during the 1995 integrated monitoring study in California's
San Joaquin Valley. Atmospheric Environment 33: 4775-4786.
Blumenthal, D.L., T.B. Smith, D.E. Lehrman, R.A. Rasmussen, G.Z. Whitten, and R.A. Baxter. 1985.
Southern San Joaquin Valley ozone study. Final Report. Prepared for Western Oil & Gas
Association, Los Angeles. Contract #84-8.0.05(2)-07-01 by Sonoma Tech., Inc., and Systems
Applications, Inc.
Bradford, D.F. 1983. Winterkill, oxygen relations and energy metabolism of a submerged dormant
amphibian, Rana muscosa. Ecology 64:1171-1183.
Bradford, D.F. 1989. Allotopic distribution of native frogs and introduced fishes in high Sierra Nevada
lakes of California: Implication of the negative effect offish introductions. Copeia 1989: 775-778.
Bradford, D.F., M.S. Gordon, D.F. Johnson, R.D. Andrews, and W.B. Jennings. 1994a. Acidic
deposition as an unlikely cause for amphibian population declines in the Sierra Nevada, California.
Biological Conservation 69: 155-161.
35
-------
Bradford, D.F., D.M. Graber, and F. Tabatabai. 1994b. Population declines of the native frog, Rana
muscosa, in Sequoia and Kings Canyon National Parks, California. Southwestern Naturalist 39: 323-327.
Bradford, D.F., S.D. Cooper, T.M. Jenkins, Jr., K. Kratz, O. Sarnelle, and A.D. Brown. 1998. Influences
of natural acidity and introduced fish on faunal assemblages in California alpine lakes. Canadian
Journal of Fisheries and Aquatic Sciences 55: 2478-2491.
Bridges, C.M., and R.D. Semlitsch. 2000. Variation in pesticide tolerance of tadpoles among and within
species of Ranidae and patterns of amphibian decline. Conservation Biology 14: 1490-1499.
Cahill, T.C., J.J. Carroll, D. Campbell, and I.E. Gill. 1996. Air quality. Pp. 1227-1261 in Sierra
Nevada Ecosystem Project: Final report to Congress, vol. n, Assessments and scientific basis for
management options. Davis: University of California, Centers for Water and Wildland Resources.
Carey, C., N. Cohen, and L. Rollins-Smith. 1999. Amphibian declines: an immunological perspective.
Developmental and Comparative Immunology 23: 459-472.
Carroll, J.J., and R.L. Baskett. 1979. Dependence of air quality in a remote location on local and
mesoscale transports: a case study. Journal of Applied Meteorology 18: 474-486.
Cleveland, W.S., and S.J. Devlin. 1988. Locally weighted regression: an approach to regression analysis
by local fitting. Journal of the American Statistical Society 83: 596-610.
Cory, L., P. Fjeld, and W. Serat. 1970. Distribution patterns of DDT residues in the Sierra Nevada
mountains. Pesticides Monitoring Journal 3: 204-211.
Datta, S., L. Hansen, L. McConnell, J. Baker, J. LeNoir, and J.N. Seiber. 1998. Pesticides and PCB
contaminants in fish and tadpoles from the Kaweah River basin, California. Bulletin Environmental
Contamination and Toxicology 60: 829-836.
Davidson, C., H.B. Shaffer, and M.R. Jennings. Declines of the California red-legged frog: spatial
analysis of the climate, UV-B, habitat, and pesticides hypotheses. Ecological Applications, in press.
Davidson, C., H.B. Shaffer, and M.R. Jennings. Spatial tests of alternative hypotheses for California
amphibian declines. Manuscript in review.
Davis, J.C. 1973. Statistical and data analysis in geology. John Wiley & Sons, New York.
Donald, D.B., J. Syrgiannis, R.W. Crosley, G. Holdsworth, D.C.G. Muir, B. Rosenberg, A. Sole, and
D.W. Schindler. 1999. Delayed deposition of organochlorine pesticides at a temperate glacier.
Environmental Science and Technology 33: 1794-1798.
Drost, C.A., and G.M. Fellers. 1996. Collapse of a regional frog fauna in the Yosemite area of the
California Sierra Nevada, USA. Conservation Biology 10: 414-425.
Ellman, G.L., K.D. Courtney, V. Andres, Jr., and R.M. Featherstone. 1961. A new and rapid
colorimetric determination of acetylcholinesterase activity. Biochemistry and Pharmacology 7: 88-
36
-------
Engewald, W., J. Teske, and J. Efer. 1999. Programmed temperature vaporisers-based large volume
injection in capillary gas chromatography. Journal of Chromatography A 842: 143-161.
Englund, E., and A. Sparks. 1991. GEO-EAS 1.2.1, Geostatistical Environmental Assessment Software.
EPA 600/8-91/008, Las Vegas, Nevada, USA.
Ewell, D.M., R.G. Flocchini, and L.O. Myrup. 1989. Aerosol transport in the southern Sierra Nevada.
Journal of Applied Meteorology 28: 112-125.
Perm, M., and H. Hultberg. 1999. Dry deposition and internal circulation of nitrogen, sulfur and base
cations to a coniferous forest. Atmospheric Environment 33: 4421-4430.
Fernandez, P., R.M. Vilanova, and J.O. Grimalt. 1999. Sediment fluxes of polycyclic aromatic
hydrocarbons in European high altitude mountain lakes. Environmental Science and Technology 33:
3716-3722.
Franz, T.P., S.J. Eisenreich, and T.M. Holsen. 1998. Dry deposition of particulate polychlorinated
biphenyls and polycyclic aromatic hydrocarbons to Lake Michigan. Environmental Science and
Technology 32: 3681-3688.
Hastie, T., and R. Tibshirani. 1991. Generalized additive models. Chapman and Hall, London.
Hayes, T.P., J.J.R. Kinney, and N.J.M. Wheeler. 1984. California surface wind climatology. California
Air Resources Board, Aerometric Data Division, Sacramento.
Hongve, D. 1972. En bunnhenter som er lett a lage. Fauna 25:281-283.
Jennings, M.R., and M.P. Hayes. 1994. Amphibian and reptile species of special concern in California.
Final report, Contract No. 8023, California Department of Fish and Game, Inland Fisheries Division,
Rancho Cordova, CA.
Journel, A.G., and ChJ. Huijbregts. 1978. Mining Geostatistics. Academic Press, New York.
Kagarise Sherman, C. 1980. A comparison of the natural history and mating system of two anurans:
Yosemite toads (Bufo canorus) and black toads (Bufo exul). PhD. Dissertation, University of
Michigan, Ann Arbor, Michigan.
Karlstrom, E.L. 1962. The toad genus Bufo in the Sierra Nevada of California. University of California
Publications in Zoology 62(1): 1-104.
Knapp, R.A., and K.R. Matthews. 2000. Non-native fish introductions and the decline of the mountain
yellow-legged frog from within protected areas. Conservation Biology, 14: 428-438.
37
-------
Landers, D.H., J.L. Stoddard, and D. Muir. 2000. Organic pollutant deposition to the Sierra Nevada
(California, USA) snowpack and associated lake and stream ecosystems. First International
Conference on Trans-Pacific Transport of Atmospheric Contaminants, July 27-29, 2000, Seattle,
WA.
Lehrman, D.E., T.B. Smith, and W.R. Knuth. 1998. Integrated monitoring study data analysis:
meteorological representativeness of fog and low clouds characteristics. California Air Resources
Board, Sacramento.
LeNoir, J.S., L.L. McConnell, G.M. Fellers, T.M. Cahill, and J.N. Seiber. 1999. Summertime transport
of current-use pesticides from California's Central Valley to the Sierra Nevada mountain range,
USA. Environmental Toxicology and Chemistry 18: 2715-2722.
Li, Y.-F., A. iVIcMillan, and M. T. Scholtz. 1996. Global HCH usage with 1 x 1 longitude/latitude
resolution. Environmental Science and Technology 30: 3525-3533.
Matthews, K.R., and K.L. Pope. 1999. A telemetric study of the movement patterns and habitat use of
Rana muscosa, the mountain yellow-legged frog, in a high-elevation basin in Kings Canyon National
Park, California. Journal of Herpetology 33: 615-624.
McConnell, L.L., J.S. LeNoir, S. Datta, and J.N. Seiber. 1998. Wet deposition of current-use pesticides
in the Sierra Nevada mountain range, California, USA. Environmental Toxicology and Chemistry
17: 1908-1916.
Melack, J.M., J.L. Stoddard, and C.A. Ochs. 1985. Major ion chemistry and sensitivity to acid
precipitation of Sierra Nevada lakes. Water Resources Research 21: 27-32.
Muir, D.C.G., N.P. Grift, W.L. Lockhart, P. Wilkinson, B.N. Billeck, and G.J. Brunskill. 1995. Speatial
trends and historical profiles of organochlorine pesticides in Arctic lake sedients. Science of the
Total Environment 160/161: 447-457.
Odabasi, M., A. Sofuoglu, N. Vardar, Y. Tasdemir, and T.M. Holsen. 1999. Measurement of dry
deposition and air-water exchange of polycyclic aromatic hydrocarbons with the water surface
sampler. Environmental Science and Technology 33: 426-434.
Okumura, T., and Y. Nishikawa. 1995. Determination of organophosphate pesticides in environmental
samples by capillary gas chromatography-mass spectrometry. Journal of Chromatography A
709:319-331.
Oregon State University. 1996. Extension Toxicology Network Pesticide Information Profiles.
http://ace.orst.edu/info/extoxnet/pips/ghindex.html.
Pearson, R.F., D.L. Swackhamer, S.J. Eisenreich, and D.T. Long. 1997. Concentrations, accumulations,
and inventories of polychlorinated dibenzo-p-dioxins and dibenzofurans in sediments of the great
lakes. Environmental Science and Technology 31: 2903-2909.
38
-------
Pinel-Alloul, B., C. Guay, N. Angeli, P. Legendre, P. Dutilleul, G. Balvay, D. Gerdeaux, and J. Guillard.
1999. Large-scale spatial heterogeneity of macrozooplankton in Lake of Geneva. Canadian Journal
of Fisheries and Aquatic Sciences 56: 1437-1451.
Prest, H.F., L.A. Jacobson, and J.N. Huckins. 1995. Passive sampling of water and coastal air via
semipermeable membrane devices. Chemosphere 30: 1351-1361.
Roberts, P.T., T.B. Smith, C.G. Lindsey, D.E. Lehrman, and W.R. Knuth. 1990. Analysis of San
Joaquin Valley air quality and meteorology. STI-98101-1006-FR. Prepared for San Joaquin Valley
Air Pollution Study Agency, by Sonoma Technology, Inc., Santa Rosa, CA.
Rohm and Haas. 1999. Amberlite XAD polymeric adsorbents. Rohm and Haas Company, Philadelphia,
PA.
Rose, N.L., S. Backus, H. Karlsson, and D.C.G. Muir. 2001. A historical record of toxaphene and its
congeners in a remote lake in western Europe. Environmental Science and Technology (Internet
prepublication article).
Rosenbaum, E.A., A. Caballero de Castro, L. Gauna, A.M. Pechen de D'angelo. 1988. Early
biochemical changes produced by malathion on toad embryos. Archives of Environmental
Contamination and Toxicology 17: 831-835.
Seiber, J.N., and J.E. Woodrow. 1998. Air transport of pesticides. Reviews in Toxicology 2: 287-294.
Shair, F.H. 1995. Atmospheric tracer experiments aimed at characterizing upslope/downslope flows
along the southwestern region of the Sierra Nevada mountains. Final Report, Contract No. A4-126-
32, California Air Resources Board, Sacramento.
Shelton, L.R., and P.D. Capel. 1994. Guidelines for collecting and processing samples of stream bed
sediment for analysis of trace elements and organic contaminants for the National Water-Quality
Assessment Program. Open-File Report 94-458. http://water.wr.usgs.gov/pnsp/pest.rep/bs-t.html.
U.S. Geological Survey, Sacramento, CA.
Sheskin, D. 2000. Handbook of parametric and nonparametric statistical procedures. Chapman &
Hall/CRC Press, London.
Smith, T.B., and D.E. Lehrman. 1996. SARMAP n design analysis of the San Joaquin Valley
meteorological environment during high PM10 loading. Prepared by Technical & Business Systems
Inc. for the California Air Resources Board, Sacramento.
Smith, T.B., D.E. Lehrman, D.D. Reible, and F.H. Shair. 1981. The origin and fate of airborne
pollutants within the San Joaquin Valley. Report prepared for California Air Resources Board,
Sacramento. 7 vols.
Sparling, D.W., G.M. Fellers, and L.L. McConnell. Pesticides and amphibian population declines in
California, USA. Environmental Toxicology, in press.
39
-------
Staniewski, J., H.-G. Janssen, J.A. Rijks, and C.A. Cramers. 1993. Introduction of large volumes of
methylene chloride in capillary GC with electron capture detection. Journal of Microcolumn
Separations 5: 429-432.
State of California. 1999. Data provided from database of pesticide application reports. Department of
Pesticide Regulation. Sacramento, CA.
Stohlgren, T.J., J.M. Melack, A.M. Esperanza, and D.J. Parsons. 1991. Atmospheric deposition and
solute export in giant sequoia-mixed conifer watersheds in the Sierra Nevada, California.
Biogeochemistry 12: 207-230.
ter Braak C.J.F., and P. Smilauer. 1998. CANOCO Reference Manual and User's Guide to Canoco for
Window. Software for Canonical Community Ordination (version 4). Centre for Biometry
Wageningen.
Thompson, S.K. 1992. Sampling. John Wiley & Sons, New York.
Thurman, E.M., and A.E. Cromwell. 2000. Atmospheric transport, deposition, and fate of triazine
hebicides and their metabolites in pristine areas at Isle Royale National Park. Environmental Science
and Technology 34: 3079-3085.
Tracer Technologies. 1992. Transport of acidic air pollutants to forests and alpine regions of the Sierra
Nevada. Final Report, Contract No. A932-141, California Air Resources Board, Sacramento.
Turner, L.J. 1998. 210Pb dating of lacustrine sediments from Lachnagar Scotland (Core 207). Report 98-
5. National Water Research Institute, Burlington, Ontario.
U.S. Department of Agriculture. 1989. Pesticide Properties Database. Agriculture Research Service.
http://wizard.arsusda.gov/rsml/ppdb.html.
U.S. Environmental Protection Agency. 1993. The determination of organophosphorus pesticides in
municipal and industrial wastewater. Method 1657.
U.S. Fish and Wildlife Service. 2000a. Endangered and threatened wildlife and plants: 90-day finding
on a petition to list the mountain yellow-legged frog as endangered. Federal Register 65 (198):
60603-60605.
U.S. Fish and Wildlife Service. 2000b. Endangered and threatened wildlife and plants: 90-day finding
on a petition to list the Yosemite toad as endangered. Federal Register 65 (198): 60607-60609.
U.S. Geological Survey. 1998. Annual Use Maps, Pesticide National Synthesis Project.
http://water.wr.usgs.gov/pnsp/use92/.
Wania, F., and D. Mackay. 1993. Global fractionation and cold condensation of low volatility
organochlorine compounds in polar regions. Ambio22: 10-18.
40
-------
Zabik, J.M., and J.N. Seiber. 1993. Atmospheric transport of organophosphate pesticides from
California's Central Valley to the Sierra Nevada mountains. Journal of Environmental Quality 22:
80-90.
Zar, J.H. 1999. Biostatistical analysis (4th ed.). Prentice Hall, Upper Saddle River, NJ.
Zaugg, S.D., M.W. Sandstrom, S.G. Smith, K.M. Fehlberg. 1995. Methods of analysis by the U.S.
Geological Survey National Water Quality Laboratory - determination of pesticides in water by C-18
solid-phase extraction and capillary-column gas chromatography/mass spectrometry with selected-
ion monitoring. Open File Report 95-181, U.S. Geological Survey, Washington, DC.
41
-------
Appendix A
Patterns of Surface Air Movement
in the San Joaquin Valley and
Southern Sierra Nevada
A.1 Surface Air Movements in the San Joaquin Valley
During all seasons except late fall and winter, air is transported into the San Joaquin Valley (SJV)
primarily through the Carquinez Straits to the vicinity of Stockton, and thence southeast to the southern
end of the SJV (Smith et al. 1981; Hayes et al. 1984; Blumenthal et al. 1985). During summer and early
fall, this northeast-to-southeast transport is effected by surface layer winds and a low-level (100 to 1000
m) nocturnal jet (Smith et al. 1981; Blumenthal et al. 1985). Another characteristic feature during
summer hi the SJV is the early morning development of the Fresno Eddy, a counterclockwise circulation
of the lower 500-700 m of the atmosphere (Smith et al. 1981; Blumenthal et al. 1985; Roberts et al.
1990). The eddy is typically centered west of Visalia near Highway 99 and extends from about Delano
to Fresno. Together, the nocturnal jet and Fresno Eddy effectively distribute pollutants throughout the
southern part of the SJV (Smith et al. 1981; Blumenthal et al. 1985). However, a consequence of the
eddy is that pollutants on the east side of the SJV are often less dispersed and can accumulate more in
stagnant or recirculating air masses than those on the west side of the valley (Blumenthal et al. 1985).
During the afternoon in summer and early fall, mixing depths in the SJV generally increase to about
1000 m above ground level (Smith et al. 1981). Most of the air exiting the SJV goes over Tehachapi Pass
and adjacent slopes at the southern end of the valley (Smith et al. 1981; Blumenthal et al. 1985; Roberts
et al. 1990). About 15% of the air exiting the SJV goes up the Sierra slopes (Roberts et al. 1990).
Residence times for pollutants are estimated to be one to two days, depending mainly on release location
(Smith et al. 1981; Tracer Technologies 1992).
During late fall and winter, the SJV is characterized by near-stagnant conditions that are interrupted
by occasional scouring events resulting from the passage of frontal systems (Smith et al. 1981; Blanchard
et al. 1999). During an 11-year period, such intervals of poor ventilation lasted up to 19 days (Smith et
al. 1981). Maximum mixing heights during these times are often in the range of 200 to 500 m (Smith and
Lehrman 1996; Lehrman et al. 1998).
A.2 Surface Air Movements in the Southern Sierra Nevada
During summer the dominant wind regime consists of a very regular oscillation of upslope and
downslope winds controlled by the diurnal variation of solar heating of the Sierra slopes (Ewell et al.
1989; Cahill et al. 1996). This pattern is remarkably consistent from day to day except when disrupted
by synoptic-scale meteorological events. Upslope velocities generally exceed downslope velocities,
resulting in a net upslope transport. At the latitude of Sequoia National Park, depth of this terrain-driven
42
-------
Appendix B
Additional Selection Criteria for Target Analytes
There were many more than 31 pesticides, herbicides, and fungicides used in excess of 5000 kg
annually in the Central Valley near the study area. The list in Table 1 was derived using additional
criteria that would likely affect the probability of analyte detection. Those additional criteria are
summarized in Table B.I. First, the vapor pressure of target analytes must be low enough to allow
deposition and minimize subsequent volatilization. This criterion eliminated a number of fumigants that
are used in enormous quantities in the Central Valley. All 31 primary target analytes have equilibrium
vapor pressures less than 5000 mPa (<5xlO'7 atm). No minimum volatility was set for the target analytes,
since dry deposition of analyte on wind-blown particles could be a significant loading mechanism.
Second, persistence in the water column, either dissolved or sorbed on suspended particulates, must
be long enough to allow detection for at least a few weeks after deposition. Rate constants for hydrolysis
at two pH values (5 and 7) (U.S. Department of Agriculture 1989) were used to estimate half-lives for
hydrolysis. Table B.I shows that nearly all the target analytes have half-lives of at least 30 days in the
pH range 5 to 7. The exceptions are phorate and phosmet, which have maximum predicted half-lives of 3
and 9 days, respectively. However, the octanol-water partition coefficient, K,,,, for each of these
compounds is at least 103 (Table B.I). This indicates an affinity for organic matter in suspended and bed
sediment that may prolong persistence of these compounds. The other mechanisms of chemical
degradation, photolysis and microbial metabolism, were not considered as selection criteria, because
environmental factors affecting each are unpredictable. For information purposes, possible photolysis is
indicated in Table B.I when available data indicate photolysis half-lives of less than 7 days in distilled
water. It should be noted that although both diazinon and trifluralin are predicted to be rapidly
photolyzed, both have been detected in lakes in the study area (LeNoir et al. 1999). Irrespective of
whether degradation is likely, major degradation products, such as the oxygen analogs of the
phosphorothioate pesticides, will also be measured whenever possible.
Finally, all target analytes will have to be detectable by the sampling and analytical methods to be
used in the study. The methods generally require sufficient sorption on an extraction resin to effect
extraction from a large volume of water. For the resins being considered for this study, this attribute can
be roughly predicted by a high Kow. For comparison, malathion, with a Kow of about 500, was detected in
lake water in the study area using methods analogous to those planned (LeNoir et al. 1999), although the
volume of water extracted in that study was substantially less than the volumes that will be extracted in
this study. A careful evaluation of extraction efficiencies is part of the experimental design. Another
requirement for the target analytes is that they be determinable by gas chromatography/mass
spectrometry (GC/MS) using either electron-impact ionization (El) or negative chemical ionization (NCI)
with selective ion monitoring. The literature contains appropriate methods for all of the target analytes
(see references in Table B.I). Method development will determine if all of the target analytes can be
determined in a single GC/MS run using each ionization method.
44
-------
wind system decreases from about 1000 m at the edge of the SJV to about 350 m at Emerald Lake,
approximately 42 km away at 2720 m elevation (Ewell et al. 1989).
Tracer studies show that the major transport pathways from the SJV into the Sierra are the larger
river valleys (Tracer Technologies 1992). However, few data are available to describe how closely air
follows the upslope/downslope topography at the upper reaches of the major river watersheds. Tracer
studies in the Kaweah River area show that surface air moves upslope to the highest elevations sampled
(Tablelands at 3210 m elevation, 60 km from release point) by mid afternoon following tracer release
near the edge of the SJV between 2 and 8 AM (Shair 1995). Shair (1995) suggested that air converging
at major ridges from opposing upslope flows, such as the Great Western Divide separating the Kaweah
and Kern River watersheds, likely experiences considerable vertical mixing, resulting in rapid dilution by
an order of magnitude, and at least partial removal by upper level winds.
During winter air at elevations above 500 to 1000 m in the Sierra are frequently above the mixed
layer in the SJV, and thus are effectively decoupled from the air circulation in the valley (Blanchard et al.
1999; Cahill et al. 1996). Prevailing northwesterly winds dominate at these times, rather than terrain-
driven winds, and levels of pollutants in air are extremely low (Cahill et al. 1996). During winter
storms, the inversion in the SJV is broken, air motion and mixing are vigorous, and mixed air is
transported to the Sierra Nevada (Cahill et al. 1996).
43
-------
Table B.1. Factors affecting probable detection of primary target compounds listed in Table 1 .a
Compound
alachlor
azinphos methyl
butylate
carbaryl
chlorothalonil"
chlorpyrifos
cyanazine
DCPA (chlorthal dimethyl)
diazinon
dicofol
disulfoton
endosulfan (I and ll)a
EPTC
ethalfluralin
lindane (y-HCH)
linuron
malathion
methidathionh
methyl parathion
metolachlor
napropamide
pebulate
pendimethalin
permethrin
phorate
phosmet
propargite
simazine
trifluralin
tribufos'
Vapor Pressure
(mPa)
4.1
0.027
1730
0.2
0.076
2.3
0.0002
0.33
8
1.3
24
0.8
3200
12
4.4
1.5
0.7
190
0.2
1.7
0.27
1180
1.2
0.02
85
0.06
0.006
0.0008
6.7
0.213
tซ PH 7"
no data
26
700
11
stable
29
stable
stable
139
4
23 (40ฐC)
35'
stable
>30
stable'
1100
6
no data
41
stable
stable
no data
stable
stable
3
<1
77
stable
>30
stable
tin PH 5"
no data
43
700
no data
stable
77
151
stable
12
87
no data
150'
stable
>30
stable'
1100
116
no data
69
stable
stable
no data
stable
stable
3
9
122
stable
>30
stable
iog(K,ja
2.9
2.7
4.1
2.3
2.9
5.0
2.1
>59
3.1
4.3
4.0
3.1
3.3
5.1
3-3.S3
3.0
2.7
4.7
3.5-3.8'
3.0
3.3
4.0
5.2
6.1
3.9
3.0
3.7
2.1
5.1
5.5
Photolysis
Likely"
no
yes
no
no
no
no
no
no
yes
no
yes
no
no
yes
no
no
no
no data
no data
no
yes'
no
yes'
no
no
yes
no
no
yes
no
All data taken from U.S. Department of Agriculture (1989), except where noted. All values are for 20 or
25ฐC (20ฐC, if available, unless noted). All compounds are included in the GC/MS method of Zaugg et al.
(1995), except where noted. Major degradation products that will be determined are not listed.
Hydrolysis half-life in days at the pH indicated.
Logarithm of the octanol-water partition coefficient (Kow, no units).
"yes": photolysis rate constant indicates a half-life to photolysis of less than 6 days, except where noted.
Included in GC/MS method of LeNoir et al. (1999).
From Oregon State University (1996).
9 Calculated from solubilities in water and a variety of organic solvents (data in U.S. Dept. of Agriculture
1989).
Included in GC/MS method of Aston and Seiber (1997).
Included in GC/MS method of Okumura and Nishikawa (1995).
' Included in GC method of U.S. Environmental Protection Agency (1993).
45
-------
Appendix C
Use Patterns of
Six Organophosphorus Pesticides
in the San Joaquin Valley Near the Study Area
The temporal, as well as spatial, pattern of pesticide application in the SJV is highly variable. The
data provided by the Department of Pesticide Regulation (State of California 1999) for the years 1996-
1998 has been analyzed for approximate temporal (monthly time scale) and spatial (on a county basis)
characteristics. This Appendix describes some results for six Organophosphorus (OP) pesticides for the
year of median use of each. Inspection of this data, combined with the relatively short persistence of
some of the target contaminants in surface waters (Appendix B), indicates that pesticide concentrations
in lake water may exhibit significant temporal variability.
Figures C. 1 through C.6 show the use, by month and by county, of six organophosphate (OP)
pesticides for the year of median use of each in five counties in the SJV. Many OPs follow the general
temporal trend shown for chlorpyrifos (Figure C.I) and azinphos methyl (Figure C.2), i.e., much heavier
use in the summer months than the remainder of the year. However, diazinon (Figure C.3) and
methidathion (Figure C.4) were used mostly in the winter, with substantial summer use. Tribufos (Figure
C.5) was used exclusively in the fall, and phorate (Figure C.6) in the spring. Even for the OPs of
predominantly summertime use, application can vary considerably on a shorter time scale. Chlorpyrifos
use increased gradually beginning in May and peaking in August, while azinphos methyl use abruptly
began in June and declined monotonically through August.
Figi
250
200
pounds applied
Thousands
o in
0 O
50
0
jre C.1. Chlorpyrifos use by month and county
LJ * . lU - IL JL
123456
month
,
JL
I B i L _ .
7 8 9 10 11 12
Fresno
Kern
D Kings
D Madera
M Tulare
of year
46
-------
Figur
50
40
o
o- -o 30
ra S
"O 0
|| 20
Q.
10
0
e C.2. Azinphos methyl use by month and county
,L ,L 1
J
,,
1234567
month of year
I
i..
8 9 10 11 12
Fresno
Kern
D Kings
Madera
H Tulare
Figure C.3. Diazinon use by month and county
a
0
Q.
50
40
30
20
10
ll U Ll Ll Lrt Li I. i L. I . L .
D Fresno
Kern
D Kings
H Madera
H Tulare
56789
month of year
10 11 12
Fi<
30
25
> 20
o
c/l C
x ra
-------
Fi
200
150
ซ ซ
"5. -D
Q. ฃ
m ro
2 ^ 100
p
50
0
gure C.5. Tribufos use by month and county
J
1
A .
1 2 3 4 5 6 7 8 9 10 11 12
month of year
H Fresno
Kern
D Kings
Madera
B Tulare
pounds applied
Thousands
_i _>. to ro
o (n o (n o ui __
igure C.6. Phorate use by month and county
,
{
Ln_ .... I i
1 2 3 4 5 6 7 8 9 10 11 12
month of year
H Fresno
Kern
D Kings
H Madera
lH Tulare
There are also significant differences in pesticide use by county, overall as well as by season. For
example, azinphos methyl (Figure C.2) is distinguished from other OPs in that its use was dominated by
Kern County, which lies at the southern end of the SJV, presumably where the upslope winds in the Kern
River watershed originate. In the early summer, chlorpyrifos (Figure C.I) was used predominantly in
Tulare County; in the late summer, it was used mainly in Fresno County. These differences indicate that
analysis of the data from the temporal variation study, combined with simultaneous township-scale
pesticide use data from the State of California Department of Pesticide Regulation, may be sufficient to
provide some evidence of the importance of upslope surface-air transport of pesticides.
43
-------
Appendix D
Resumes of Participants
49
-------
David F. Bradford, Ph.D.
U.S. Environmental Protection Agency
National Exposure Research Laboratory
Landscape Ecology Branch
P.O. Box 93478, Las Vegas, NV 89193-3478
Telephone: (702) 798-2681 Facsimile: (702) 798-2692 e-mail: bradford.david(g),epa.gov
Education
Ph.D. in Biology, University of California, Los Angeles, 1982
M.A. in Zoology, University of California, Berkeley, 1972
B.A. in Biology, California State University, Fresno, 1968
Experience
Research Ecologist: U.S. Environmental Protection Agency, National Exposure Research Laboratory,
Las Vegas, 1992 - present.
Adjunct Faculty: Department of Biological Sciences, Univ. of Nevada, Las Vegas, NV, 1995 - present.
Visiting Assistant Professor and Research Scientist: Environmental Science and Engineering Program,
School of Public Health, University of California, Los Angeles, 1988 -1992.
Senior Biologist: Envirosphere Company, Santa Ana and Sacramento, California, 1986 -1988.
Assistant Professor: Biological Sciences Department, Northern Illinois University, 1985 -1986.
Postdoctoral Research Associate: Zoology Department, University of Adelaide, Australia, 1983 -1985.
Recent Publications
Bradford, D.F., S.E. Franson, G.R. Miller, A.C. Neale, G.E. Canterbury, and D.T. Heggem. 1998. Bird
species assemblages as indicators of biological integrity in Great Basin rangeland. Environmental
Monitoring and Assessment, 49: 1-22.
Wade, T., B. Schultz, J.D. Wickham, and D.F. Bradford. 1998. Modeling the potential spatial
distribution of beef cattle grazing using a geographic information system. Journal of Arid
Environments, 38: 325-334.
Bradford, D.F., S.D. Cooper, T.M. Jenkins, Jr., K. Kratz, O. Samelle, and A.D. Brown. 1998. Influences
of natural acidity and introduced fish on faunal assemblages in California alpine lakes. Canadian
Journal of Fisheries and Aquatic Sciences, 55: 2478-2491.
50
-------
Resume of David F. Bradford, PhD.
Continued
Wade, T.G., J.D. Wickham, and D.F. Bradford. 1999. Accuracy of road density estimates derived from
USGS DLG data for use in environmental applications. Photogrammetric Engineering & Remote
Sensing 65: 1419-142.
Ultsch, G.R., D.F. Bradford, and J. Freda. 1999. Physiology: coping with the environment. Pp. 189-214
in R.W. McDiarmid and R. Altig (eds.), Tadpoles: The Biology of Anuran Larvae. University of
Chicago Press, Chicago.
Canterbury, G.E., T.E. Martin, D.R. Petit, L.J. Petit, and D.F. Bradford. 2000. Bird communities and
habitat as ecological indicators of forest condition in regional monitoring. Conservation Biology 14:
544-558.
Bradford, D.F., R.D. Jennings, and J.R. Jaeger. Rana onca Cope 1875, relict leopard frog. Pp. 000-000
in M.J. Lannoo (ed.), Status and Conservation of U.S. Amphibians, University of California Press.
In Press.
Jaeger, J.R., B.R. Riddle, R.D. Jennings, and D.F. Bradford. Evidence for phylogenetically distinct
leopard frogs (Rana onca) from the border region of Nevada, Utah, and Arizona. Copeia. Jji Press.
51
-------
Chad L. Cross, Ph.D.
Quantitative Ecologist & Statistician
U. S. Environmental Protection Agency
National Exposure Research Laboratory, Landscape Ecology Branch
944 East Harmon Avenue, Las Vegas, Nevada 89119
Office: 702/798-2148 Facsimile: 702/798-2692 e-mail: cross.chad@.epa.gov
Education
B.S. (1993; Purdue University): Biology (Ecology, Evolutionary, and Population Biology)
B.S. (1994; Purdue University): Forestry and Natural Resources (Wildlife Science)
M.S. (1997; Old Dominion University): Computational and Applied Mathematics (Statistics)
Ph.D. (1998; Old Dominion University): Ecological Sciences (Quantitative Ecology)
Academic & Professional Positions
Purdue University, West Lafayette, Indiana. 1994. Teaching Assistant, Department of Biological
Sciences.
U. S. Fish and Wildlife Service, Back Bay National Wildlife Refuge, Virginia Beach, Virginia. 1997.
Biological Research Intern.
Old Dominion University, Norfolk, Virginia. 1998. Teaching Assistant, Department of Biological
Sciences.
Old Dominion University, Norfolk, Virginia. 1998. Lecturer, Department of Biological
Sciences/Department of Mathematics and Statistics.
Ivy Tech State College, Lafayette, Indiana. 1999 Instructor, Department of Mathematics and Biology.
U.S. Environmental Protection Agency, Environmental Sciences Division, Landscape Ecology
Branch, Las Vegas, Nevada. 1999-present. Postdoctoral Research Scientist.
University of Nevada-Las Vegas, Las Vegas, Nevada. 2000-present. Associate Graduate Faculty,
Environmental Studies Department.
Expertise
Statistical sampling design and analysis
Animal-Habitat modeling
Quantitative ecological theory and application
Herpetological conservation and population biology
52
-------
Resume of Chad L. Cross, Ph.D.
Continued
Recent Publications
1998 Cross, C. L., and C. Marshall. Agkistrodonpiscivoruspiscivorus. Predation. Herpetological
Review 29(1):43.
1998 Cross, C. L., J. B. Gallegos, F. G. James, and S. T. Williams. A new technique for artificially
incubating loggerhead sea turtle eggs. Herpetological Review 29(4):228-229.
2000 Cross, C. L. Behavioral Ecology of the eastern cottonmouth (Agkistrodon p. piscivorus) in a
natural and an anthropogenic marsh habitat in southeastern Virginia. Program Book and
Abstracts of the 80th Annual Meeting of the American Society of Ichthyologists and
Herpetologists, La Paz, B.C.S., Mexico.
2000 Cross, C. L. A new design for a lightweight squeeze box for snake field studies. Herpetological
Review 31(1):34.
2000 Cross, C. L., and P. M. Waser. Estimating population sizes of banner-tailed kangaroo rats.
Southwestern Naturalist 45(2): 176-183.
53
-------
Beth Gentry
Education
BS in Chemical Engineering (October 1998)
Worcester Polytechnic Institute (Worcester, Massachusetts)
MPH (Masters in Public Health) in Environmental Health Science (May 2001)
Tulane University School of Public Health (New Orleans, Louisiana)
Work Experience
National Network of Environmental Management Systems (NNEMS) Fellowship
Environmental Protection Agency Las Vegas, NV (June 2000 - June 2001)
Developing methods using the GC/MS to detect trace levels of pesticides
* Negative Electron Capture
> Electron lonization
Evaluating Solid Phase Extraction (SPE) Sampling Methods
Procedure, and GC/MS
Authoring Quality Assurance/Control Project Plan
Intevac: Santa Clara (January -August 1997)
Jr. Engineer (8 month internship)
Pending Patent - infrared calibrator
Tested methods of infrared temperature measurement
Designed fittings
Worked with infrared camera
Utilized Computer Skills: Autocad R13, Excel, Word, LabTech, & System Software
Allied Technology Group: Fremont (October-January 1999)
Jr. Engineer (3 month position)
Set Up Sampling Schedules for Waste Disposal
Aided hi Editing Closure Reports
Set Up Cost Tracking Systems
Certified: 40 Hour OSHA Hazardous Waste Training (29 CFR 1910.120 e)
Independent Research
Estrogenic/Androgenic Effects of Methyl Tert-Butyl Ether (MTBE) January 2000 - June 2000
Responsible for Growing Health Cells
Evaluated Level of Estrogenic/Androgenic Activity in cells using a Luminometer
Analyzed Results
Laboratory Assistant November 1999 - March 2000
Collected Water Samples
Prepared Samples Used to Evaluated an Optimal Indicator Bacteria Test
54
-------
Resume of Beth Gentry
Continued
International Project Costa Rica May 1996 - August 1996
Created Proposal to Increase Foreign Profit by Improving Service
Worked for 3 months at Atlas Electrica's Headquarters in Costa Rica
Communicated with Distributors in El Salvador, Nicaragua, Panama, and Guatemala
Membrane Filtration August 1997 - May 1997
Designed and Performed Experiments to Purify Water Using Membrane Filtration
Evaluated Membraned Filtration in Terms of a Final Cleaning Step in a Residence
55
-------
Edward M. Heithmar, Jr., Ph.D.
U.S. Environmental Protection Agency
National Exposure Research Laboratory
Environmental Chemistry Branch
P.O. Box 93478, Las Vegas, NV 89193-3478
Telephone: (702) 798-2626 Facsimile: (702) 798-2142 e-mail: heithmar.ed@epa.gov
Education
B.A. Mathematics and Chemistry, Biscayne College, Miami, FL
Ph.D. Analytical Chemistry, University of Pittsburgh
Thesis: "Application of the Hydride Generation Techniques to Continuum Source Atomic
Fluorescence Spectrometry"
Experience
Research Chemist 1997 - Present
Environmental Chemistry Branch
ESD/NERL
U. S. Environmental Protection Agency
Acting Manager 1996 - 1997
Analytical Chemistry Research Program
CRD/NERL
U. S. Environmental Protection Agency
Research Chemist 1985 - present
Analytical Chemistry Research Program
CRD/NERL
U. S. Environmental Protection Agency
Assistant Professor 1978 - 1985
Department of Chemistry
University of New Orleans
Research Interests
Environmental analytical chemistry, trace element speciation, inductively coupled plasma mass
spectrometry, hyphenated analysis techniques, sample introduction approaches for atomic spectrometry,
atomic fluorescence spectrometry, gas-phase molecular luminescence spectrometry, environmental
transport and fate of contaminants.
56
-------
Resume of Edward M. Heithmar, Jr., Ph.D.
Continued
Professional Societies
American Chemical Society
Society for Applied Spectroscopy
Selected Publications
"Investigation of arsine-generating reactions using deuterium-labeled reagents and mass spectrometry"
Pergantis, S. A.; Winnik, W.; Heithmar, E. M.; Cullen, W. R. Talanta 1997, 44, 1941-1947.
"Microscale flow injection and microbore high-performance liquid chromatography coupled with
inductively coupled plasma mass spectrometry via a high-efficiency nebulizer" Pergantis, S. A.;
Heithmar, E. M.; Hinners, T. A. Anal. Chem. 1995, 67, 4530-4535.
"Determination of metals in solid samples by complexation-supercritical fluid extraction and gas
chromatography-atomic emission detection" Liu, Y.; Lopez-Avila, V.; Alcaraz, M.; Beckert, W. F.;
Heithmar, E. M. J. Chromatogr. Sci. 1993, 31, 310-316.
"Minimization of interferences in inductively coupled plasma-mass.spectrometry using on-line
preconcentration" Heithmar, E. M.; Hinners, T. A.; Rowan, J. T.; Riviello, J. M. Anal. Chem. 1990,
62, 857-864.
57
-------
Roland A. Knapp, Ph.D.
Sierra Nevada Aquatic Research Laboratory, University of California
Star Route 1, Box 198, Mammoth Lakes, CA 93546
Telephone: (760)647-0034 Facsimile: (760) 647-6411 e-mail: knapo(g).lifesci.ucsb.edu
Current Position
Research Scientist: University of California, Santa Barbara / Marine Science Institute
Education
1986 B.A. in Aquatic Biology. University of California, Santa Barbara.
1992 Ph.D. in Biology. University of California, Santa Barbara.
Extramural Grants (Last Two Years Only)
U.S. Department of Agriculture: $83,612 July 1998 - June 1999
Introduced trout in the Sierra Nevada, California: A proposal to study their distribution and impacts on
aquatic ecosystems.
Environmental Protection Agency and National Park Service: $208,316 July 1999 - June 2002
Analysis of natural and anthropogenic factors in controlling the distribution of amphibians in the alpine
Sierra Nevada.
Yosemite Fund: $256,250 May 2000 - April 2002
Faunal surveys of Yosemite National Park's lentic habitats and their use in understanding impacts of
normative fish and designing aquatic restoration measures.
National Science Foundation: $303,000 June 2000 - June 2003
Collaborative research: Recovery of ecosystem structure and function following exotic species
eradication.
Publications (Last Five Years Only)
1996 Knapp, R. A., and V. T. Vredenburg. Spawning by California golden trout: characteristics of
spawning fish, seasonal and daily timing, redd characteristics, and microhabitat preferences.
Transactions of the American Fisheries Society 125: 519-531.
1996 Knapp, R. A., and V. T. Vredenburg. A field comparison of the substrate composition of
California golden trout redds sampled with two devices. No. Amer. J. Fish. Mgmt. 16: 674-681.
1996 Knapp, R. A., and K. M. Matthews. Livestock grazing, golden trout, and streams in the Golden
Trout Wilderness, California: impacts and management implications. No. Amer. J. Fish. Mgmt.
16: 805-820.
58
-------
Resume of Roland A. Knapp, Ph.D.
Continued
1998 Knapp, R. A., and K. M. Matthews. Eradication of non-native fish by gill netting from a small
mountain lake in California. Restoration Ecology 6: 207-213.
1998 Knapp, R. A., V. T. Vredenburg, and K. M. Matthews. The effect of stream channel morphology
on golden trout spawning habitat and recruitment. Ecological Applications 8: 1104-1117.
1999 Matthews, K. R., and R. A. Knapp. A study of high mountain lake fish stocking effects in the U.S.
Sierra Nevada wilderness. International Journal of Wilderness 5: 24-26.
1999 Knapp, R. A., and H. K. Preisler. Is it possible to predict habitat use by spawning salmonids? A
test using the California golden trout (Oncorhynchus mykiss aguabonitd). Canadian Journal of
Fisheries and Aquatic Sciences 56: 1576-1584.
2000 Knapp, R. A. and K. R. Matthews. Nonnative fish introductions and the decline of the mountain
yellow-legged frog (Rana muscosa) from within protected areas. Conservation Biology 14: 428-
438.
2000 Knapp, R. A., J. A. Garton, and O. Samelle. The use of egg shells to infer the historical presence
of copepods in alpine lakes. Journal of Paleolimnology, in press.
2000 Knapp, R. A., K. R. Matthews, and O. Sarnelle. Resistance and resilience of alpine lake faunal
assemblages to fish introductions. Ecological Monographs, in press.
59
-------
Georges-Marie Momplaisir, Ph.D.
U.S. Environmental Protection Agency
National Exposure Research Laboratory
Environmental Chemistry Branch
P.O. Box 93478, Las Vegas, NV 89193-3478
Telephone: (702)798-2255 e-mail: momDlaisir.georges-marie(g>epa.gov
Educational Background
1995 Ph.D. Chemistry, McGill University, Department of Food Science and Agricultural Chemistry
Thesis title: Development of Analytical Methods for the Speciation of Arsenic in the Marine
Environment.
1989 B.Sc. Chemistry, Montreal University, Department of Chemistry
Professional Experience
Research Chemist April 1999 to Present
U.S. Environmental Protection Agency, NERL/ORD. Trace element speciation in environmental
samples, using on-line coupled techniques.
Research Chemist /Laboratory Coordinator December 1998 - April 1999
University of Nevada Las Vegas, Harry Reid Center for Environmental Studies, Las Vegas NV. The
research work involved the development of analytical methods based on Hydride Generation coupled
with atomic absorption spectrometry for the identification and quantification of naturally occurring
inorganic arsenic, selenium and antimony species in groundwaters collected in the Southern Nevada
region. Such information was necessary in order to determine the oxidizing/reducing properties of the
groundwaters. The total concentrations of the elements in the water samples were corroborated by
Inductively Coupled Plasma Mass Spectrometry analyses. I also act as laboratory coordinator for the
groundwater geochemistry group.
Post-Doctorate Fellowship of the National Research Council 1995-1998
U.S. Environmental Protection Agency (EPA), at the National Exposure Research Laboratory,
Characterization Division in Las Vegas, NV. Research in the area of Trace Element Speciation Using
High-Performance Liquid Chromatography-Inductively Coupled Plasma/Mass Spectrometry (HPLC-
ICPMS), HPLC-Electrospray-MS/MS, HPLC-AAS and GC-MS.
Research Associate 1993-1994
McGill University, Department of Food Science & Agricultural Chemistry. Speciation of Arsenic and
Selenium in Sediments, Sediments Porewaters and seafoods by High Performance Liquid
Chromatography-Atomic Absorption Spectrometry.
60
-------
Resume of Georges-Marie Momplaisir, Ph.D.
Continued
Field Experience
Survey Cruise along the Saguenay River from Rimousky to Chicoutimy, sponsored by Fisheries and
Ocean Canada (May 1991 and May 1992). Collection and preservation of samples of sediments and
sediment porewaters for arsenic speciation.
Selected Publications and Presentation
Marshall, W.D. and Momplaisir, G.M., "Chromatographic Approaches to Trace Element Speciation " in
Metal Speciation and Bioavailability in Aquatic Systems, Tessier, A., and Turner, D. Eds., John
Wiley and Sons LTD 1995, Chap. 7.
Momplaisir. G.M.. Lei, T. and Marshall, W.D., "Performance of a Novel Silica T-tube Interface for the
AAS Detection of Arsenic and Selenium Compounds in HPLC Column Eluate," Anal. Chem. 1994,
66, pp 3533-3539.
Tan, Y., Momplaisir. G.M.. Wang, J. and Marshall, W.D., "Performance of a Silica T-tube Interface for
the AAS Detection of Cadmium, Copper, Lead, Zinc and Mercury in Flowing Liquid Streams," J.
Anal. At. Spectrom. 1994, 9, pp. 1153-1159.
Momplaisir, G.M., Betowski, L.D. and Winnick, W., "Determination of Nine Organoselenium
Compounds Using High-Performance Liquid Chromatography Coupled with Electrospray Mass
Spectrometry" 46th ASMS Conference on Mass Spectrometry and Allied Topics, Orlando, Florida,
June 1-5, 1998.
Pergantis, S.A.. Momplaisir. G.M.. Heithmar, E.M. and Hinners, T.A., "Speciation of Arsenic in
References Materials by Using Micro-HPLC/ICPMS, 44th ASMS Conference on Mass Spectrometry
& Allied Topics, Portland, Oregon, May 12-16, 1996.
Momplaisir, G.M., Lei, T. and Marshall, W.D. "Speciation of Arsenic and Selenium by FIPLC-AAS,"
24th International Symposium on Environmental Analytical Chemistry, Ottawa, Canada, May 1994.
61
-------
Maliha S. Nash, Ph.D.
U.S. Environmental Protection Agency
National Exposure Research Laboratory
Landscape Ecology Branch
P.O. Box 93478, Las Vegas, NV 89193-3478
Telephone: (702) 798-2201 Facsimile: (702) 798-2692 e-mail: nash.maliha@eoa.gov
Education
Soil Physics / Geostatistics and Experimental Statistics (Ph.D.), New Mexico State University
Soil Physics / Geostatistics and Experimental Statistics (M.S.), New Mexico State University
Agricultural Engineering / Soil Science (B.S.)
Research Interest
Developing space-time models to characterize responses of biological variables to environmental change.
Developing indicators and indices for biotic and abiotic variables based on geostatistical techniques.
Using parametric and nonparametric multivariate analyses (CART, GAM, MARS) to analyze binary
(present/absence) data as related to environmental variables.
Work History
July 1998 - present, US EPA, Physical Scientist (3-year post doctoral position), U.S. EPA, ORD, NERL,
LEB, Las Vegas Nevada. Developing GIS and remote sensing, watershed-based modeling and
statistics for interpolating the consequences of landscape changes on aquatic and terrestrial
resources.
May 1998 - June 1998, New Mexico State University, Research Specialist, based at U.S. EPA, ORD,
NERL, CRD, Las Vegas Nevada. Geostatistical analysis on mammal, vegetation and ant data for the
multiple stressor project.
May 1995 - April 1998, National Research Council, Research Associate, U.S. EPA, ORD, NERL, CRD,
Las Vegas Nevada. Research focused on evaluating ecosystem properties and processes that may
change in a predictable pattern along gradients of disturbance, particularly those associated with
livestock grazing.
March 1992 - May 1995, Hydrogeologist, Foothill Engineering Co. / U. S. Geological Survey, Nuclear
Hydrology Program, Nevada Test Site, Mercury, Nevada. Study of water movement, distribution and
status in relation with geological formations at Yucca Mountain, Nevada.
62
-------
Resume of Maliha S. Nash, Ph.D.
Continued
Recent Publications
Nash, M.S., W.G. Whitford, A.G. de Soyza, J. Vanzee, andK. Havstad. 1999. Livestock activity and
Chihuahuan Desert annual plant communities: Boundary analysis of disturbance gradients.
Ecological Applications 9: 814-823.
Nash, M.S., W.G. Whitford, J. Vanzee, and K. Havstad. 2000. Ant (Homoptera, Formicidae) response to
environmental stressors in the northern Chihuahuan Desert. Environmental Entomology 29: 200-206.
Jones K.B., A.C. Neale, M.S. Nash, K.H. Riitters, J.D. Wickham, R.V. O'Neill and R.D. Van Remortel.
2000. Landscape correlates of breeding bird richness across the United State Mid-Atlantic region.
Environmental Monitoring and Assessment 63:159-174.
Jones KB, Heggem DT, Wade TG, Neale AC, Nash MS, Mehaffey MH, Hermann KA, Selle AR,
Augustine S, Goodman IA. Pedersen J, Bolgrien D, Viger JM, Chaing D, Lin CJ, Zhong Y, Baker J,
and Van Remortel R. 2000. Assessing landscape condition relative to water resources in the
western United States: Strategic approach. Environmental Monitoring and Assessment 64:227-245.
Pitchford A., J.M. Denver, A.R. Olsen, S.W. Ator, S. Cormier, M.S. Nash, and M. Mehaffey. 2000.
Testing landscape indicators for stream condition related to pesticides and nutrients: Landscape
indicators for pesticides study for mid-Atlantic coastal streams (LIPS-MACS). EPA/600/R-00/87.
USEPA, ORD, Washington DC 20460.
Nash, M.S., and W.G. Whitford. In Press. Ants as biological indicators for monitoring changes in arid
environments: lessons for monitoring protected areas. Proceedings of 1st International Symposium
and Workshop on Arid Zone Environment Research and Management Options for Protected Areas.
Jan 23-25, 2000, Abu Dhabi, UAE.
63
-------
Nita Tallent-Halsell
U. S. Environmental Protection Agency
Landscape Ecology Branch, Environmental Sciences Division,
Box 93478, Las Vegas, Nevada 89183-3478
Telephone: (702)798-2487
Education
Master of Arts in Science, Biology/Statistics, University of Nevada, Las Vegas, 1998
Bachelor of Science, University of Nevada, Las Vegas, 1989
Experience
Ecosystem Restoration Research
LEB Remote Sensing, GIS and Landscape Ecology Training Coordinator
LEB Global Positioning Systems Lead
ESD-LV Health and Safety Committee Chairperson
EMAP - Forest Health Monitoring, National Logistics Coordinator (1993-1995)
EMAP - Surface Waters Logistics Coordinator (1991)
EMAP - Arid Lands Logistics Coordinator (1992-93)
Publications
Tallent-Halsell, N. and L. R. Walker, (in prep). Lake Mohave Riparian Ecology and Restoration.
Tallent-Halsell, N. and L. R. Walker, (in prep). Response of Salix gooddingii and Tamarix ramosissima
to flooding and substrate types.
Tallent-Halsell, N. and L.R. Walker, (in prep). Management recommendations for Lake Mohave riparian
sustainabiliry and restoration.
de Soyza, A. G., J. W. Van Zee, W. G. Whitford, A. Neale, N. Tallent-Halsell, J. E. Herrick and K. M.
Havastad. (2000) Indicators of Great Basin rangeland health. Journal of Arid Environments. 45:289-
304.
Tallent-Halsell, N. 1995. Training Strategies for Ecological Monitoring Programs: The Forest Health
Monitoring Experience, p. 398-408. In: Power, J.M., M. Strome and T.C. Daniel (editors). 1995.
Proceedings of Decision Support - 2001 Vol. I, Toronto, Canada September, 12-16,1994. American
Society of Photogrammetry and Remote Sensing, Bethesda, Maryland, USA.
Tallent-Halsell, N. (ed). 1994. Forest Health Monitoring Field Methods Guide. EPA/620/R-94/027. U.S.
Environmental Protection Agency, Washington, D.C.
64
-------
Resume of Nita Tallent-Halsell
Continued
Kepner, W.G., R.O. Kuehl, R.P. Brechenridge, J.M. Lancaster, S.G. Leonard, D.A. Mouat, T.G. Reinsch,
K.B. Jones, A.C. Neale, T.B. Minor, and N. Tallent-Halsell. 1994. Environmental Monitoring and
Assessment Program: Arid Ecosystems 1992 Pilot Report. EPA/620/R-94/015. U. S. Environmental
Protection Agency, Washington, DC.
Tallent-Halsell, N. 1993. Logistics In: Franson, S. 1993. Environmental Monitoring and Assessment
Program: EMAP-Arid Colorado Plateau Pilot Study - 1992 Implementation Plan. EPA/600/7-93.
U.S. Environmental Protection Agency, Washington, DC.
Presentations, Posters and Published Abstracts
Tallent-Halsell, N. and L.R. Walker. 1999. Southwestern Sustainability along a Lower Colorado River
Impoundment. Mojave Desert Science Symposium, February 25-26, 1999, Las Vegas, Nevada.
Tallent-Halsell, N. 1998. Developing a conceptual model of landscape and ecosystem dynamics for
riparian restoration on a lower Colorado River Impoundment. Society of Ecological Restoration
Conference, September 27-30, 1998. Austin, Texas.
Tallent-Halsell, N. and L. R. Walker. 1998. Riparian species response to inundation and drought: a
greenhouse experiment on Salix gooddingii and Tamarix ramosissima cuttings. Ecological Society
of America-83rd Annual Meeting, August 2-6, 1998, Baltimore, Maryland.
Tallent-Halsell, N. 1998. Southwestern Riparian Sustainability and Restoration in a Man-made
Ecosystem. National Symposium on Ecosystem Restoration, July 29-31, 1998, Baltimore, Maryland.
Tallent-Halsell, N. and L.R. Walker. 1997. Goodding Willow Ecology in a man-made southwestern
riparian ecosystem. Presented at 1997 Ecological Society of America Meeting, August 10-14, 1997.
Albuquerque, New Mexico.
Tallent-Halsell, N. 1997. Goodding Willow Ecology on the Shoreline of Lake Mohave. Presented at
Forty First Annual Meeting of the Arizona - Nevada Academy of Science, April 19, 1997. University
of Nevada, LV.
65
-------
Lee Riddick
Education
1984-1987, Louisiana State University: Microbiology
1996, B.S. University of Nevada, Las Vegas: Chemistry
Experience
Research Chemist, Environmental Chemistry Branch, BSD, NERL, U.S. EPA, 1996-present
NNEMS Fellow, U.S. EPA, Las Vegas, NV 1993-1996
Biochemistry Technician, University of Nevada, Las Vegas 1992-1993
Expertise/Research
Method development using Capillary Electrophoresis (CE) and GC-MS for detection of
environmental pollutants.
66
-------
Charlita Rosal
U.S. Environmental Protection Agency
National Exposure Research Laboratory
Environmental Chemistry Branch
P.O. Box 93478, Las Vegas, NV 89193-3478
Telephone: (702) 798-2179 e-mail: rosal.charlitafo).eoa.gov
Educational Background
M.S. Environmental Chemistry, 1991
University of Nevada Las Vegas
Thesis title: Poloniwn-210 Radioactivity in Lake Mead Fish
M.S. (ABT) Chemical/Environmental Engineering, 1980-82
University of the Philippines, Diliman, Quezon City, Philippines
B.S. Chemical Engineering, 1979
Mindanao State University, Marawi, Philippines
Professional Experience
Research Environmental Scientist June 1990 to Present
U.S. Environmental Protection Agency, NERL/ORD
Current research involves method development for speciation of arsenic from environmental samples
using capillary electrophoresis/UV (CE/UV) and CE/inductively coupled plasma mass spectrometry
(CE/ICPMS). Performs multielement inorganic analyses on PRIMENet and other environmental
samples. First 5 years of Agency work involved in research, development, and evaluation of new and
improved methods for environmental monitoring and characterization of waste sites. Served as a
Project Officer for research related to underground storage tanks, ground-water/surface water, and
saturated zone monitoring and characterization of surface/subsurface environmental conditions and
contaminants.
Nuclear Research Scientist 1979 - 1982
Philippine Atomic Energy Commission, Diliman, Quezon City, Philippines
Performed routine processing of radioisotopes consisting of target preparation, irradiation of
samples, chemical processing and/or purifying of irradiated materials and activity assaying of the
products. Prepared soil samples for irradiation for uranium analysis using delayed neutron activation
analysis. Involved in tests and experiments in radioimmunoassay. Performed routine dispensing and
quality assurance/quality control of radioisotopes for human use.
67
-------
Katrina E. Varner
US EPA/NERL-LV
Environmental Sciences Division/Environmental Chemistry Branch
P.O. Box 93478/Las Vegas, NV 89193-3478
Education
B.S., Developmental and Cellular Biology, minor in Social Services, University of Nevada, Reno, 1987
Experience
1990-Present Environmental Research Scientist, U.S. Environmental Protection Agency, Las Vegas
1989-1990 Organic Chemist, FiberChem, Inc.
1987-1989 Chemist I, Las Vegas Valley Water District
Publications
Amick, E.N., Pollard, J.E., and Varner, K.E., "An Evaluation of Four Field Screening Techniques for
Measurement of BTEX," EPA/600/R-94/181, U.S. Environmental Protection Agency. September
1994.
Portnoff, M.A. and Varner, K.E., "Measurement and Analysis of Vapor Sensors Used at Underground
Storage Tank Sites," EPA/600/R-95/181, U.S. Environmental Protection Agency. May 1995.
Kreamer, D.K., James, D.E., and Varner, K.E., "Determination of Pollutant Distribution and Movement
by Controlled Laboratory Experiments," EPA/600/R-96, U.S. Environmental Protection Agency.
November 1996.
Hampton, D.R. and Varner, K.E., "Improving Free Product Monitoring and Recovery," EPA/600/R-97,
U.S. Environmental Protection Agency.
Amick, E.N. and Varner, K.E., "Field Analysis of Soil and Water Samples for Petroleum Hydrocarbons
at Sites in Las Vegas, Nevada Utilizing Quick Turnaround Methods," EPA/600/R-97, U.S.
Environmental Protection Agency.
Eskes, C., Honegger, P., Jones-Lepp, T., Varner, K., Mattheiu, J.M., and Monnet-Tschudi, F.
"Neurotoxicity of Dibutyltin in Aggregating Brain Cell Cultures," Toxicology in Vitro, 13 (1999),
555-560.
Lepp-Jones, T., Varner, K., McDaniel, M. and Riddick, L. "Determination of Organotins in Water by
Micro-Liquid Chromatography-Electrospray Ion Trap Mass Spectrometry," Applied Organometallic
Chemistry, 1999.
Jones-Lepp, T. and Varner, K. "Speciation and Detection of Organotins from PVC pipe by Micro-Liquid
Chromatography-Electrospray Ion Trap Mass Spectrometry" Analytical Chemistry, under review,
1999.
68
-------
Resume of Katrina E. Varner
Continued
Varner, K. and Jones-Lepp, T. "Development and application of a micro-liquid
chromatography-electrospray/ion trap mass spectrometry method for the detection of two susPฎc*e
endocrine disrupters: Dibutyltin and triphenyltin, in natural waters and fish tissue" National ACb
Proceedings 1999.
Jones-Lepp, T. and Varner, K. "Development and Application of a Solid Phase Extraction and
Micro-liquid Chromatography-electrospray/ion trap Mass Spectrometry Method for Detecting Three
Pharmaceuticals in Natural Waters: Prozac, Prilosec, and Claritan" American Water Works
Association, American Research Foundation Conference, 1999.
Presentations
Varner, K.E. 1994. Monitoring Hydrocarbons at UST Sites. USEPA Region 9All-States Meeting. Lake
Tahoe, CA.
Varner, K.E. 1995. Field Screening Methods for BTEX. USEPA Technical Support Project
Meeting/Engineering and Ground Water Forum. Las Vegas, Nevada.
Varner, K.E. 1996. Expedited Site Assessment Methods for Underground Storage Tank Facilities
Workshop. Martinsburg, West Virginia and Kansas City, Missouri.
Jones, T.L., Varner, K.E., and Riddick, L.A. 1997. Using ^-Liquid Chromatography Electrospray-Ion
Trap Mass Spectrometry to Measure Organotins in an Ambient Environment. 45th American Society
for Mass Spectrometry and Allied Topics Conference. Palm Springs, California.
Eskes, C., Honegger, P., Monnet-Tschudi, F., Jones-Lepp, T., and Varner, K. 1998. Toxicity of
Dibutyltin in Aggregating Brain Cell Culture: Comparison with Trimethyltin and Triethyltin.
Environmental Toxocolgy Conference, 1998. London, England.
Varner, K.E. and Jones, T.L. 1998. "Organotins, They're Everywhere. Are They Coming to You?"
NERL-LV Research Expo. Las Vegas, NV.
Varner, K.E. 1999. "Dibutvltin Measured in Brain using u-Liquid Chromatographv Electrosprav/Mass
Spectrometry" Western Regional ACS Pacific Conference on Chemistry and Spectroscopy, Ontario,
CA.
69
-------
Appendix E
Environmental Chemistry Branch
Facilities/Instrumentation
The Environmental Chemistry Branch (ECB), BSD, NERL-Las Vegas, comprises 4000 ft2 of
laboratory space. The labs contain a dozen fume hoods, as well as glove boxes, clean benches, and a
HEPA-filtered instrument room for low-level analyses. The branch maintains a wide array of in-house
state-of-the-art analytical instruments for preparation, separation, and detection of organic, inorganic, and
organometallic stressors and indicators of exposure.
Organics: ECB possesses several mass spectrometers. A Finnigan-MAT 900S-Trap with position-
and time-resolved ion-counting focal-plane detector can perform high-resolution MS and MSn
experiments at ultra-low concentrations. A VG 70-250SE is also available for high-resolution MS.
Other mass spectrometers include a Finnigan TSQ 700, three Agilent 6890 GC/5973 MSDs (one with
PCI/NCI), Hewlett-Packard 5890 GC/5972 MSD, Varian Saturn H Ion Trap GC/MS, Finnigan GCQ Ion
Trap GC/MS, Finnigan 4000, and two ThermoQuest LCQs. In addition to gas chromatography and
liquid chromatography (through electrospray interface) sample introduction, some of these mass
spectrometers can be configured with fast atom bombardment and solid probes.
Three Beckman capillary electrophoresis instruments have variable UV detectors, diode array
detector, and Ar ion laser (488 nm) detector. A stand-alone optical bench with laser sources is available
(located at UNLV). A 5W medium scale Ar ion laser allows access to all of the Ar ion lines including
the deep UV from frequency doubling; a 2.5W Ar/Kr mixed-gas laser W increases the number of lines
available, including the near IR region; also available are Liconix HeCd 354 nm and 325 nm lasers, and
HeNe 595 nm 633 nm lasers. A Beckman CE/MS interface for quadrupole mass spectrometers is also
available.
Other instrumentation includes an Hewlett-Packard 5890 Series n GC with electronic pressure
programming and autosampler with FID and BCD and a 5890 GC with autosampler and NPD.
Hewlett-Packard 5890 Series n Plus GC with 5921A He-plasma atomic emission detector (AED) and
electronic pressure programming is used for selective gas chromatographic determination of compounds
containing heteroatoms. A Spex Fluorolog 2 spectrofluorimeter, a Perkin-Elmer Lambda 9 spectrometer,
Spectra-Physics liquid chromatograph with diode array and fluorescence detectors, and CAMAG
instrumental thin-layer chromatography system (consisting of TLC spotter, automated multiple
development instrument, and computer-controlled densitometer with UV, visible, and fluorescence
detection) are also in-house. Other instrumentation includes two HP 1090 HPLCs with DAD and
programmable fluorescence detectors, and a custom made vacuum distillation apparatus with HP
GC/MSD.
70
-------
For sample preparation and cleanup, the following equipment is available: a Hewlett-Packard
supercritical fluid extraction instrument and supercritical fluid chromatograph, a Suprex Prepmas er ,
a Waters Millenium HPLCS for high performance gel permeation chromatography, a Danaus ASE 200
thermally assisted solvent extraction instrument, a Savant ISS110 Integrated SpeedVac system for
concentration of DNA samples, a Forma Scientific 4520 incubator shaker, and Zymark TurboVap 500
and TurboVap n evaporators.
Inorganics: Element-specific detection systems include a VG PlasmaQuad n STEICPMS, wnicn
can be equipped with a Mistral desolvation unit (VG Elemental) for ultra-high sensitivity, and Thermo
Jarrell Ash AA Scan 4 atomic absorption spectrometer equipped with a Model 188 graphite furnace
atomizer. The VG ICPMS is installed hi a room supplied with HEPA-filtered air. Syringe pumps (ISCO
model 100DM) and reciprocating pumps (Dionex microscale gradient pumps) are available for delivery
of liquid flows required for different modes of microscale high-performance liquid chromatography.
Milestone automatic mercury analyzer for fluids and tissues/solids (requiring no liquid reagents). Various
extraction and digestion systems (heating block, steam distillation, etc.) are available.
Computers: One Silicon Graphics Indigo 2 workstation and three SGI Octanes are in-house, with
access to UNLV or Bay City Cray supercomputers.
71
------- |