DSHW-2006-007003 - 0901a068801658d8

For Official Use Only

For Official Use Only
U.S. Army
Chemical Materials Agency
Program Manager for the Elimination
of Chemical Weapons
2005 Environmental Monitoring
Follow-on Study Report
Tooele Chemical Agent Disposal Facility
Tooele, Utah
Final
For Official Use Only

For Official Use Only
U.S. Army
Chemical Materials Agency
Program Manager for the Elimination
of Chemical Weapons
2005 Environmental Monitoring
Follow-on Study Report
Tooele Chemical Agent Disposal Facility
Tooele, Utah
Final
May 2006

i
EXECUTIVE SUMMARY

This report presents the results of the fourth (2005) Environmental Monitoring Follow-on
Study (EMFS) for the Tooele Chemical Agent Disposal Facility (TOCDF) located at the
Deseret Chemical Depot (DCD) in north-central Utah, approximately 20 miles south of
the city of Tooele. Incineration of chemical warfare materiel began at TOCDF in
August 1996. The EMFS is an evaluation of changes to the environment surrounding
TOCDF since chemical agent destruction was initiated.

During the 2005 EMFS, samples of surface soil, vegetation (shrub and herbaceous),
were collected from the permanent sampling locations established by the
1996 Environmental Monitoring Baseline Study (EMBS) and subsequent EMFSs (1998,
1999, and 2002). Fifteen new soil and vegetation sampling locations were added for
the 2005 EMFS. Surface water and sediment samples were also collected from
Rainbow Reservoir and Ophir Creek. All samples were submitted to environmental
testing laboratories for chemical analysis.

A statistical evaluation of the EMFS chemical data for surface soil, water, sediment, and
vegetation samples was performed to determine if the mean concentration of any
chemical of potential concern (COPC) has shown a statistically significant increase
relative to the baseline data. The maximum concentrations for COPCs identified above
detection limits in the 2005 EMFS were first compared to EMBS screening criteria
comprised of the baseline 99 percent upper tolerance level (UTL) or the baseline
maximum value (if no UTL was calculated). Those analytes where the 2005 value
exceeded the EMBS screening level were retained for further statistical analysis.
Common laboratory contaminants (acetone, methylene chloride, 2-butanone, and
various phthalates) were excluded from statistical analysis. The concentrations of
COPCs that indicated statistically significant increases or were of general environmental
interest were evaluated temporally and spatially. Commonly abundant metals
(aluminum, boron, calcium, copper, iron, magnesium, manganese, potassium, sodium,

ii
and zinc) found in the soil and vegetation of the geographic region were typically
excluded from further evaluation.

COPCs that were below reporting limits in the EMBS but were identified above the
detection limits in the 2005 EMFS were designated as statistically indeterminate.
Statistically indeterminate COPCs were evaluated relative to their detection frequency,
the baseline and 2005 EMFS reporting limits, the baseline maximum concentrations,
and environmental relevance. Those indeterminate COPCs exhibiting relatively high
detection frequencies at similar or higher reporting limits, coupled with mean and/or
maximum concentrations above the EMBS reporting limit or of particular environmental
interest, were retained for temporal and spatial evaluation.

Spatial distribution was evaluated by mapping COPC concentrations recorded for each
site and comparing any apparent trends to the particulate deposition pattern predicted
by the EMBS air dispersion model. Historic data from the EMBS and each EMFS were
evaluated by analyzing trends in group mean values and discrete concentrations at
individual sample sites. Table ES-1, located at the end of this section, is a summary of
the 2005 EMFS results for COPCs in soil, shrub, and herbaceous samples that were
evaluated statistically, spatially, and temporally. None of the COPCs in water or
sediment samples met the criteria for spatial or temporal evaluation.

Surface Soil Results

Forty-eight analytes were detected in 2005 EMFS soil samples, 22 of which had also
been detected in the 1996 EMBS. There were 3 analytes detected in the EMBS that
were not detected in the 2005 EMFS. Considering the 22 analytes detected in both the
2005 EMFS and the EMBS, 13 (all metals) showed a statistically significant or
apparently higher concentration in 2005 versus 1996. The remainder of the analytes
showed a statistically or apparent decrease in concentration. Further evaluation
resulted in 7 metals (arsenic, barium, beryllium, cadmium, chromium, cobalt, and
vanadium) being retained for spatial and temporal evaluation.

iii
Of the 26 analytes detected in the 2005 EMFS but not in the 1996 EMBS, there was
sufficient information to evaluate 18 by nonparametric and graphical methods. All 18 of
these analytes showed an apparent decrease in concentration relative to the EMBS
reporting limits. From this group of analytes, mercury was retained for spatial and
temporal evaluation because of special interest in this chemical by the State of Utah.

Spatial and temporal evaluation of surface soil data concluded that none of the COPCs
displayed a trend indicative of a relationship to the location of the TOCDF common
stack or the time line of TOCDF incineration operations.

Shrub Sample Results

Thirty-eight analytes were detected in shrub samples in the 2005 EMFS, of which
16 had also been detected in the 1996 EMBS. There were 3 analytes detected in the
EMBS that were not detected in the 2005 EMFS. Considering the 16 analytes detected
in both the 2005 EMFS and 1996 EMBS, 14 (13 metals and one dioxin) showed a
statistically significant or apparent increase in concentration relative to baseline levels.
The other 2 analytes exhibited an apparent decrease in concentration in the
2005 EMFS. Upon further evaluation, 3 metals (barium, mercury, and tin) and the
dioxin, OCDD, were retained for spatial and temporal evaluation.

Of the 22 analytes detected in shrub samples in the 2005 EMFS but not detected in the
EMBS, 21 were evaluated by nonparametric and graphical methods (the common
laboratory contaminant di-n-butyl phthalate was not evaluated). Of the 21 analytes
evaluated, 13 analytes (2 metals, 7 dioxins/furans, and 4 explosive compounds) showed
apparent or possible increased concentrations versus baseline reporting limits. The
other 8 analytes exhibited apparent decreases in concentration or a concentration that
had not changed. After further evaluation, 5 analytes (chromium, molybdenum,
2,4,6-trinitrotoluene [TNT], cyclonite [RDX], and total dioxins/furans) were retained for
spatial and temporal evaluation and 2 analytes (2,4-dinitrotoluene[2,4-DNT] and high
melting explosive [HMX]) were retained for temporal evaluation only.

iv
Spatial and temporal evaluation of shrub data concluded that none of the COPCs
displayed a trend indicative of a relationship to the location of the TOCDF common
stack or the time line of TOCDF incineration operations.

Herbaceous Sample Results

Thirty-nine analytes were detected in herbaceous samples during the 2005 EMFS, of
which 20 had also been detected in the 1996 EMBS. There were 3 analytes detected in
EMBS herbaceous samples that were not detected in the 2005 EMFS. Of the
20 analytes detected in the EMBS and the 2005 EMFS, 19 were statistically evaluated
(the common laboratory contaminant bis-2-(ethylhexyl)-phthalate was not evaluated).
Nine of these analytes (6 metals, one dioxin, and 2 explosives compounds) showed a
statistically significant, apparent, or possible increase in concentration. The other
10 analytes exhibited a statistically significant or apparent decrease in concentration.

Upon further evaluation, two analytes (molybdenum and total dioxin/furan) were
retained for spatial and temporal evaluation. In addition, 3 explosives compounds
(2,4-DNT, nitroglycerin, and HMX) were retained for temporal evaluation only.

The 19 analytes detected in herbaceous samples during the 2005 EMFS but not
detected in the EMBS, were compared to the EMBS laboratory reporting limits. An
apparent or possible increase in concentration was seen in 13 of the analytes (3 metals,
7 dioxins/furans, and 3 explosives compounds) and an apparent decrease was seen in
6 analytes. Three analytes (cadmium, mercury, and total dioxin/furan) were retained for
spatial and temporal analysis. Three other compounds (TNT, RDX, and tetryl) were
retained for temporal evaluation only.

Spatial and temporal evaluation of herbaceous vegetation data lead to the conclusion
that none of the COPCs displayed a trend indicative of a relationship to the location of
the TOCDF common stack or the time line of TOCDF incineration operations.

v
Surface Water and Sediment

Two surface water and collocated sediment samples were collected from Rainbow
Reservoir and 1 surface water and collocated sediment sample was collected from
Ophir Creek near the entrance to the diversion pipe that carries water from the creek to
the reservoir. Because of the history of Rainbow Reservoir and the fact that Ophir
Creek was not sampled during the EMBS, all comparisons between baseline and
follow-on data were qualitative; therefore, no statistical evaluation was performed.

Considering only the water samples, there was only one analyte (calcium) in the
Rainbow Reservoir that had a 2005 EMFS concentration that exceeded the EMBS
maximum detected concentration or 99 percent UTL. In the Ophir Creek water sample,
4 analytes (aluminum, calcium, iron, and magnesium) had concentrations greater than
the levels found in Rainbow Reservoir during the EMBS.

In the sediment samples, calcium in Rainbow Reservoir and chromium in Ophir Creek
were the only analytes in the 2005 EMFS where the concentrations exceeded the
maximum detected value or 99 percent UTL for Rainbow Reservoir in the EMFS.

None of the analytes from the water and sediment samples were retained for spatial or
temporal evaluation.

Conclusions

Based on data evaluated during the 2005 EMFS, it is concluded that variations in shrub
and herb: frequency, cover, density, diversity, forage value, and decreaser/increaser
index, are not associated with emissions from the TCODF common stack. Furthermore,
it is concluded that variations in the concentration of chemicals of potential concern in
soil, vegetation, water, and sediment are not associated with emissions from the
TOCDF common stack in either spatial or temporal distribution. No evidence was found
that operation of the TOCDF incinerator has had an effect on the surrounding
environment.

vi
Table ES-1. Summary of 2005 EMFS Chemical Results

Detected in Both
1996 EMBS and 2005 EMFS
Detected Only in
2005 EMFS
Analytical
Parameter Analytes
Detected
Exceeded
EMBS
Screening
Criteria
Statistically
Significant or
Apparent
Increase
Retained
for Spatial
Evaluation
Analytes
Detected
Retained
for Spatial
Evaluation
Spatial or
Temporal
Trend
Associated
with TOCDF
Common
Stack
Soil Samples
Anions N/A N/A N/A N/A N/A N/A N/A
Dioxin/
Furan 0 0 0 0 10 0 No
Explosives 0 0 0 0 4 0 No
Metals 22 19 13 7 4 1 No
PCB 0 0 0 0 0 0 No
SVOC 0 0 0 0 1 0 No
VOC N/A N/A N/A N/A 7 0 No
Shrub Samples
Anions N/A N/A N/A N/A N/A N/A N/A
Dioxin/
Furan 1 1 1 0 7
Total dioxins
& furans No
Explosives 2 0 0 0 4 2 No
Metals 13 11 13 3 9 2 No
PCB 0 0 0 0 0 0 No
SVOC 0 0 0 0 2 0 No
VOC N/A N/A N/A N/A N/A N/A N/A
Herbaceous Samples
Anions N/A N/A N/A N/A N/A N/A N/A
Dioxin/
Furan 1 1 1 1 7
Total dioxins
& furans No
Explosives 2 2 2 0 3 0 No
Metals 15 10 6 1 8 2 No
PCB 0 0 0 0 0 0 No
SVOC 2 1 0 0 1 0 No
VOC N/A N/A N/A N/A N/A N/A N/A

Notes:

EMBS = Environmental Monitoring Baseline Study
EMFS = Environmental Monitoring Follow-on Study
N/A = not applicable
PCB = polychlorinated biphenyl
SVOC = semivolatile organic compound
TOCDF = Tooele Chemical Agent Disposal Facility
VOC = volatile organic compound

vii
TABLE OF CONTENTS

Section/Paragraph Title Page

1 INTRODUCTION...............................................................................................1-1
1.1 Project Background ................................................................................1-1
1.1.1 TOCDF.........................................................................................1-1
1.1.2 Environmental Monitoring Studies................................................1-2
1.2 Purpose and Scope ................................................................................1-2
1.3 Document Organization ..........................................................................1-3

2 REVIEW OF PREVIOUS STUDIES ..................................................................2-1
2.1 1996 EMBS.............................................................................................2-1
2.1.1 Summary of Field Effort ...............................................................2-1
2.1.2 Evaluation of Chemical Data........................................................2-3
2.1.3 Statistical Analysis of Analytical Data...........................................2-3
2.2 1998 EMFS.............................................................................................2-4
2.3 1999 EMFS.............................................................................................2-6
2.4 2002 EMFS.............................................................................................2-7

3 ENVIRONMENTAL SETTING ...........................................................................3-1
3.1 Air Quality...............................................................................................3-1
3.2 Precipitation............................................................................................3-2
3.3 Population...............................................................................................3-3
3.4 Local Fire History....................................................................................3-3

4 STUDY METHODOLOGY.................................................................................4-1
4.1 Sample Locations ...................................................................................4-1
4.1.1 Sample Locations Retained from Previous Studies .....................4-1
4.1.2 Sample Locations Added for the 2005 EMFS ..............................4-1
4.1.3 Sample Location Deviations.........................................................4-2
4.1.4 Sample Collection Schedule ........................................................4-3
4.2 Sample Media.........................................................................................4-4
4.2.1 Soil...............................................................................................4-4
4.2.2 Vegetation....................................................................................4-4
4.2.3 Surface Water and Sediment.......................................................4-4
4.3 Numbers of Samples ..............................................................................4-5
4.4 Sampling and Analytical Parameters......................................................4-5
4.5 Statistical Analysis ..................................................................................4-6
4.5.1 Vegetative Characterization.........................................................4-7
4.5.2 Shrub Layer .................................................................................4-7
4.5.3 Comparison to Previous Studies..................................................4-9

viii
TABLE OF CONTENTS (Continued)

Section/Paragraph Title Page

5 STUDY COMPARABILITY ASSESSMENT.......................................................5-1
5.1 Chemical Analysis Data..........................................................................5-1
5.1.1 Laboratory Comparability.............................................................5-2
5.1.2 Analytical Limitations....................................................................5-4
5.2 Seasonal Variability ................................................................................5-6
5.3 Data Evaluation Criteria..........................................................................5-7

6 CHARACTERIZATION RESULTS – PLANT COMMUNITIES
AND SOIL..........................................................................................................6-1
6.1 Physical Characterization of Sample Locations......................................6-1
6.2 Characterization of Vegetation Composition and Structure ....................6-2
6.2.1 Shrub Layer Characterization ......................................................6-4
6.2.2 Herbaceous Layer Characterization.............................................6-6
6.3 Vegetation Summary and Comparison to Previous Studies ...................6-7
6.3.1 Shrub Data Comparison to Previous Studies ...............................6-8
6.3.2 Herbaceous Data Comparisons...................................................6-9

7 CHEMICAL RESULTS – GENERAL .................................................................7-1
7.1 Chemical Data Assessment....................................................................7-1
7.1.1 Chemical Data Validation Results................................................7-2
7.2 Statistical Approach ................................................................................7-3

8 CHEMICAL RESULTS – SOIL ..........................................................................8-1
8.1 Surface Soil COPCs Detected (Step 1) ..................................................8-1
8.2 Surface Soil COPC Distributions (Step 2)...............................................8-3
8.3 Surface Soil Summary Statistics (Step 3)...............................................8-3
8.4 Surface Soil Comparison to Screening Levels (Step 4)..........................8-4
8.5 Surface Soil Statistical Evaluation (Step 5).............................................8-5
8.5.1 Central Tendency Tests...............................................................8-5
8.5.2 Statistically Indeterminate COPC.................................................8-7
8.6 Spatial Distribution and Temporal Trends in Surface Soil (Step 6).......8-11

9 CHEMICAL RESULTS – WATER AND SEDIMENT..........................................9-1
9.1 Surface Water Sample Results...............................................................9-1
9.2 Sediment Sample Results.......................................................................9-4

10 CHEMICAL RESULTS – SHRUB VEGETATION............................................10-1
10.1 Shrub COPCs Detected (Step 1)..........................................................10-1
10.2 Shrub COPC Distributions (Step 2) ......................................................10-2
10.3 Shrub COPC Summary Statistics (Step 3)............................................10-3
10.4 Shrub COPC Comparison to Screening Levels (Step 4) ......................10-3

ix
TABLE OF CONTENTS (Continued)

Section/Paragraph Title Page

10.5 Shrub COPC Statistical Evaluation (Step 5).........................................10-4
10.5.1 Central Tendency Tests ............................................................10-4
10.5.2 Statistically Indeterminate COPCs............................................10-6
10.6 Spatial Distribution and Temporal Trends in Shrubs (Step 6).............10-12

11 CHEMICAL RESULTS – HERBACEOUS VEGETATION ...............................11-1
11.1 Herbaceous COPCs Detected (Step 1) ................................................11-1
11.2 Herbaceous COPC Distributions (Step 2).............................................11-2
11.3 Herbaceous Summary Statistics (Step 3).............................................11-2
11.4 Herbaceous COPC Comparison to Screening Levels (Step 4).............11-3
11.5 Herbaceous COPC Statistical Evaluation (Step 5) ...............................11-4
11.5.1 Central Tendency Tests ............................................................11-4
11.5.2 Statistically Indeterminate or Inconclusive COPCs...................11-5
11.6 Spatial Distribution and Temporal Trends in Herbaceous
Samples (Step 6)................................................................................11-11

12 SUMMARY AND CONCLUSIONS ..................................................................12-1
12.1 Statistical Approach for Chemical Data.................................................12-1
12.2 Physical Characterization .....................................................................12-2
12.2.1 Shrub Species...........................................................................12-3
12.2.2 Herbaceous Species .................................................................12-4
12.3 Chemical Data Assessment ..................................................................12-5
12.3.1 Surface Soil ..............................................................................12-6
12.3.2 Vegetation.................................................................................12-6
12.3.3 Surface Water and Sediment....................................................12-8
12.4 Conclusions..........................................................................................12-9

13 RECOMMENDATIONS ...................................................................................13-1

ANNEX A ACRONYMS AND ABBREVIATIONS
ANNEX B REFERENCES
ANNEX C FIELD DATA AND LABORATORY RESULTS

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xi
LIST OF ILLUSTRATIONS

Figure Title Page

1.1-1 Regional Aerial Photograph...........................................................................1-5

3.1-1 Common Stack Air Dispersion Model..........................................................3-11
3.4-1 Range/Forest Fire .......................................................................................3-12

4.1-1 Sample Location Map ..................................................................................4-13
4.1-2 Rainbow Reservoir Sample Location ..........................................................4-14

6.2-1 Dominant Shrub Species .............................................................................6-49
6.2-2 Percent Shrub Coverage Map and Relative Dominance Distribution..........6-50
6.2-3 Dominant Herb Species...............................................................................6-51
6.2-4 Percent Herbaceous Coverage Map and Relative Dominance
Distribution ..................................................................................................6-52
6.3-1 Clumps Per Hectare Histogram Chart (Shrubs) ..........................................6-53
6.3-2 Average Height Classification Histogram Chart (Shrubs)............................6-54
6.3-3 Areal Coverage Per Hectare Histogram Chart (Shrubs)..............................6-55
6.3-4 Percent Total Vegetation Coverage Map ....................................................6-56

8.6-1 Spatial Distribution of Arsenic Concentration in Soil....................................8-34
8-6.2 Arsenic Soil Concentrations Temporal Trends............................................8-35
8.6-3 Spatial Distribution of Barium Concentration in Soil ....................................8-36
8.6-4 Barium Soil Concentrations Temporal Trends.............................................8-37
8.6-5 Spatial Distribution of Beryllium Concentration in Soil .................................8-38
8.6-6 Beryllium Soil Concentrations Temporal Trends .........................................8-39
8.6-7 Spatial Distribution of Cadmium Concentration in Soil ................................8-40
8.6-8 Cadmium Soil Concentrations Historic Trends............................................8-41
8.6-9 Spatial Distribution of Chromium Concentration in Soil...............................8-42
8.6-10 Chromium Soil Concentrations Temporal Trends........................................8-43
8.6-11 Spatial Distribution of Cobalt Concentration in Soil .....................................8-44
8.6-12 Cobalt Soil Concentrations Historic Trends.................................................8-45
8.6-13 Spatial Distribution of Mercury Concentration in Soil ...................................8-46
8.6-14 Mercury Soil Concentrations Temporal Trends...........................................8-47
8.6-15 Spatial Distribution of Vanadium Concentration in Soil ...............................8-48
8.6-16 Vanadium Soil Concentrations Temporal Trends........................................8-49

10.6-1 Spatial Distribution of Barium Concentration in Shrubs .............................10-32
10.6-2 Barium Shrub Concentrations Temporal Trends.......................................10-33
10.6-3 Spatial Distribution of Chromium Concentration in Shrubs........................10-34
10.6-4 Chromium Shrub Concentrations Historic Trends.....................................10-35
10.6-5 Spatial Distribution of Mercury Concentration in Shrubs ...........................10-36
10.6-6 Mercury Shrub Concentrations Temporal Trends......................................10-37
10.6-7 Spatial Distribution of Molybdenum Concentration in Shrubs....................10-38

xii
LIST OF ILLUSTRATIONS (Continued)

Figure Title Page

10.6-8 Molybdenum Shrub Concentrations Historic Trends .................................10-39
10.6-9 Spatial Distribution of Tin Concentration in Shrubs ...................................10-40
10.6-10 Tin Shrub Concentrations Temporal Trends..............................................10-41
10.6-11 Spatial Distribution of Dioxin/Furan Concentration in Shrubs....................10-42
10.6-12 Dioxin/Furan Shrub Concentrations Temporal Trends ..............................10-43
10.6-13 Spatial Distribution of RDX Concentration in Shrubs.................................10-44
10.6-14 RDX Shrub Concentrations Temporal Trends...........................................10-45
10.6-15 Spatial Distribution of TNT Concentration in Shrubs .................................10-46
10.6-16 TNT Shrub Concentrations Temporal Trends............................................10-47

11.6-1 Spatial Distribution of Cadmium Concentration in Herbs...........................11-28
11.6-2 Cadmium Herbs Concentrations Temporal Trends ...................................11-29
11.6-3 Spatial Distribution of Mercury Concentration in Herbs.............................11-30
11.6-4 Mercury Herb Concentrations Temporal Trends .......................................11-31
11.6-5 Spatial Distribution of Molybdenum Concentration in Herbs......................11-32
11.6-6 Molybdenum Herb Concentrations Temporal Trends................................11-33
11.6-7 Spatial Distribution of Dioxins/Furans Concentration in Herbs..................11-34
11.6-8 Dioxins/Furans Herb Concentrations Temporal Trends ............................11-35

xiii
LIST OF TABLES

Table Title Page

2.1.3-1 Summary of Mean Surface Soil Results ...................................................2-10
2.1.3-2 Summary of Mean Sediment Data............................................................2-12
2.1.3-3 Summary of Mean Water Data .................................................................2-14
2.1.3-4 Summary of Mean Shrub Data .................................................................2-16
2.1.3-5 Summary of Mean Herbaceous Data........................................................2-18

3.4-1 Range Fires in Rush Valley 1996 through 2004 .........................................3-6

4.4-1 Analytical Parameters for Soil, Vegetation, Surface Water,
and Sediment............................................................................................4-11
4.5.2.1-1 Ranking Scale for Forage Value...............................................................4-12

6.1-1 Sample Location Physical Variables ..........................................................6-14
6.1-2 Soil Samples Collected for the 2005 EMFS ...............................................6-16
6.2-1 Plant Species List.......................................................................................6-35
6.2-2 Shrub Community Composition..................................................................6-39
6.2-3 Herbaceous Community Composition........................................................6-42
6.3-1 Summary of 2005 Vegetation Characteristics............................................6-46
6.3.2.1-1 Herbaceous Vegetation Comparison 1996 Through 2005 .........................6-48

8.1-1 Detection Frequency – Surface Soil...........................................................8-20
8.2-1 Distribution Test Results – Surface Soil.....................................................8-23
8.2-2 Summary Statistics – Surface Soil .............................................................8-26
8.4-1 Means Testing – Surface Soil ....................................................................8-29

9.1-1 Comparison to 1996 Screening Criteria – Surface Water Samples..............9-6
9.2-1 Comparison to 1996 Screening Criteria – Sediment Samples ...................9-13

10.1-1 Detection Frequency – Shrub Data..........................................................10-19
10.2-1 Distribution Test Results – Shrub Vegetation...........................................10-22
10.3-1 Summary Statistics – Shrub Vegetation...................................................10-25
10.4-1 Means Testing – Shrub Vegetation..........................................................10-28

11.1-1 Detection Frequency – Herbaceous Vegetation.......................................11-15
11.2-1 Distribution Test Results – Herbaceous Vegetation.................................11-18
11.3-1 Summary Statistics – Herbaceous Vegetation.........................................11-21
11.4-1 Means Testing – Herbaceous Vegetation ................................................11-24

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1-1
SECTION 1
INTRODUCTION

This report presents the field and laboratory results obtained during the
2005 Environmental Monitoring Follow-on Study (EMFS) at Tooele Chemical Agent
Disposal Facility (TOCDF), evaluation of the data, conclusions reached, and
recommendations for future studies to be conducted for TOCDF.

1.1 Project Background

The TOCDF is located near the center of Deseret Chemical Depot (DCD) in
north-central Utah, approximately 20 miles south of the city of Tooele.
Figure 1.1-1 shows the location of DCD and TOCDF in relation to surrounding
communities and landmarks in Rush Valley. The mission of DCD is the storage and
disposal of a wide array of chemical munitions. At its peak, DCD stored approximately
40 percent (by weight) of the total U.S. stockpile of chemical agents.

1.1.1 TOCDF. The TOCDF site covers 11 hectares (27 acres) of relatively level
ground, which slopes gently to the northwest. No permanent surface streams are
present on or near the disposal facility.

The TOCDF incineration system is designed to perform thermal destruction of chemical
agents and decontaminate the munitions or bulk containers that contain the chemical
agent. The overall process consists of draining the liquid chemical agent from the
storage container/munition, followed by destruction of the agent, deactivation of
explosives, and thermal decontamination of the drained parts.

Demilitarization is accomplished using three incinerator systems that share a common
42.7-meter (140-foot) stack. Each incinerator is equipped with a dedicated pollution
abatement system and the common stack is continuously monitored for chemical agent
emissions.

1-2
1.1.2 Environmental Monitoring Studies. In order to evaluate the potential
environmental impact of incinerator emissions on the surrounding area, an
environmental monitoring study was begun in 1996 before incinerator operations began.
The initial round of environmental sampling (referred to as the Environmental Monitoring
Baseline Study [EMBS]) was conducted in May 1996. TOCDF began chemical agent
operations in August of the same year. Follow-on studies have been performed in
October 1998, May 1999, and May 2002. The current EMFS sampling round was
performed in May 2005.

To obtain comparable data, 1998, 1999, 2002, and 2005 EMFS samples were collected
from permanent sampling locations established by the 1996 EMBS and follow-on
EMFSs in accordance with program procedures. Fifteen new locations were added in
2005 to improve confidence in decisions made based on mapping of data. Sampled
media included surface soil, surface water, sediment, and two types of vegetative
growth (shrubs and grasses). Subsurface soil was not included in the 2005 study. The
analytical suite of parameters and methodologies selected for the 2005 follow-on study
were consistent with the EMBS; however, anions and nutrients were eliminated during
the 2005 study, since these parameters have shown no statistically significant changes.
In 2005, volatile organic compounds (VOCs) were only analyzed in the soil samples
from the 15 new sample sites. These changes were made in coordination with the
TOCDF Field Office, DCD, and the Utah Department of Environmental Quality (DEQ).

1.2 Purpose and Scope

The purpose of the follow-on study is to collect information on sample site
characteristics and concentrations of chemicals present in the environment surrounding
TOCDF following full-scale chemical agent destruction operations, and to compare the
data collected to that collected during the EMBS and each subsequent EMFS. The
baseline data, collected in May 1996, serve as a benchmark against which subsequent
EMFSs are compared to identify and evaluate any environmental changes over time.

1-3
This 2005 EMFS report provides a review of the environmental monitoring data from the
EMBS and the four subsequent EMFSs at TOCDF, identifies any problems or issues
associated with data comparison, and makes recommendations for future sampling
events. This data review includes results from the 1996 EMBS, 1998 EMFS,
1999 EMFS, 2002 EMFS, and 2005 EMFS. Literature searches were also used in the
preparation of this report. The primary objective of the report is to evaluate the data
generated under the environmental monitoring program and to make recommendations
for implementing changes in sampling and analysis methodologies to maximize the
technical quality of the project. Previous studies are discussed with general summaries
and conclusions to establish a basis for recommended changes. Detailed results of the
previous studies can be obtained in the referenced supporting documents.

1.3 Document Organization

This document is divided into the following sections:

• Section 1 presents the general project description, history, and document
organization.

• Section 2 provides a review and synopsis of the 1996 EMBS and
subsequent EMFSs performed in 1998, 1999, and 2002.

• Section 3 provides background information on the study area,
environmental setting, and known environmental issues in the vicinity.

• Section 4 identifies issues associated with EMBS/EMFS sampling plan
design, deviations from the established protocol, and concerns with
previous study results.

• Section 5 provides an assessment of the comparability of data derived
from the 2005 EMFS with data from the previous studies.

1-4
• Section 6 presents site characterization data that describe the soil, terrain,
and vegetation at the sample locations.

• Section 7 presents general information pertaining to chemical analytical
samples and statistical treatment of that data.

• Section 8 presents results from chemical analysis of soil samples and the
comparison of that data to baseline.

• Section 9 presents results from chemical analysis of water and sediment
samples and the comparison of that data to baseline.

• Section 10 presents results from chemical analysis of shrub vegetation
samples and the comparison of that data to baseline.

• Section 11 presents results from chemical analysis of herbaceous
vegetation samples and the comparison of that data to baseline.

• Section 12 presents the conclusions and a discussion of the comparison
results.

• Section 13 provides a series of recommendations designed to maximize
data comparability and usability.

Throughout this report, figures and tables have been grouped at the end of their
associated section. Individual figures and tables are arranged in numerical order within
each section. Table and figure numbering designations are based on the paragraph in
which each is first cited, along with a sequential number. For example, figure 4.1-1 is
the first figure cited in paragraph 4.1 and figure 4.1-2 would be the second figure cited in
that paragraph.

1-5
Figure 1.1-1. Regional Aerial Photograph

1-6
(This page intentionally left blank.)

2-1
SECTION 2
REVIEW OF PREVIOUS STUDIES

This section summarizes the results obtained in the baseline study (1996 EMBS) and
subsequent follow-on studies (1998 EMFS, 1999 EMFS, and 2002 EMFS).

2.1 1996 EMBS

The EMBS was performed in May 1996 to assess the chemical concentrations for
various environmental media and to characterize the vegetation in the vicinity of TOCDF
before full-scale incineration of chemical agents was begun.

2.1.1 Summary of Field Effort. To establish a baseline, surface soil, subsurface soil,
shrub vegetation, herbaceous vegetation, surface water, and sediment were collected
and analyzed for VOCs, semivolatile organic compounds (SVOCs), polychlorinated
biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated
dibenzofurans (PCDFs), explosives, metals, and anions. Physical characteristics of the
shrub and herbaceous vegetation also were catalogued in the report titled, Final
Technical Report, Environmental Monitoring Baseline Study, Deseret Chemical Depot
(Dames & Moore, 1997a).

A symmetric grid coordinate system was established around TOCDF and the grid nodes
were evaluated as potential sample locations. The sample locations were distributed in
a wide area around TOCDF (see figure 3.1-1). Air dispersion modeling, aerial
photographs, and property records were used to aid in selecting soil and vegetation
baseline sampling locations. (Dames & Moore, 1996). Air dispersion modeling was
performed using the Industrial Source Complex, Version 3 (ISC3) air dispersion model
developed by the U.S. Environmental Protection Agency (USEPA) (USEPA, 1995), to
designate areas with greater, lesser, and negligible potential for deposition of particulate
matter emanating from the TOCDF common stack. In order to identify the appropriate
locations for long-term sampling, each node was evaluated for proximity to other

2-2
anthropogenic sources, the presence of appropriate plant species, and accessibility
(land ownership and right-of-entry). Land usages that were less disruptive to soil and
vegetation were given preferential consideration. Sample sites were placed in low use
areas to minimize the impacts on sample site integrity from anthropogenic and animal
activities. The most suitable sampling locations were deemed to be open range with
average shrub density and low grazing intensity.

Sampling locations were selected to include points with different potential for deposition
of particulate matter from TOCDF. Surface water and sediment samples were collected
from Rainbow Reservoir.

Vegetation samples were selected for analysis to yield a total concentration of analytes
both in and on plant tissue. To minimize variability associated with various species,
shrub and herbaceous vegetation samples were selected from similar species. The
dominant shrub at most locations was big sagebrush (Artemisia tridentata) and the
herbaceous layer at most locations was dominated by cheatgrass (Bromus tectorum),
longspine sandbur (Cenchrus longispinus), and Indian rice grass (Achnatherum
(Oryzopsis) hymenoides). Shrub sampling involved the collection of shoots from the big
sagebrush, or the Utah juniper (Juniperus osteosperma) if there was not a suitable
specimen of sagebrush. Shrub samples were collected by clipping leafy branches from
different parts of the shrub to create a composite sample (Dames & Moore, 1997a).
Herbaceous samples were collected by clipping the aboveground parts of one or more
plants to obtain the required amount of material. All sampling locations were found to
be highly disturbed low-quality rangeland. Shrub and herbaceous samples were
collected at each of 25 sample locations, with the exception of location 0707 where no
shrubs were available and one location where the herbaceous sample was inadvertently
omitted.

Surface soil was sampled to capture the most recently deposited material. One surface
soil sample was collected from each of 21 sample locations. Five surface soil samples
were collected at each of 5 additional locations to provide data for statistical
calculations. Three subsurface soil samples were collected from each of 5 soil borings

2-3
to establish a soil profile representing the herbaceous root zone, the shrub root zone,
and deeper soil.

Five surface water and five sediment samples were collected from Rainbow Reservoir.

2.1.2 Evaluation of Chemical Data. Metals and anions were generally detected at
expected natural levels. Sporadic detections of VOCs and SVOCs were evaluated
based on the likelihood that they may have resulted from contamination during sample
handling or were artifacts of the analytical procedure. Acetone, methylene chloride, and
bis(2-ethylhexyl) phthalate were detected in some samples, but were determined to be
laboratory contaminants and not related to TOCDF operations. Low levels of
explosives, PCBs, PCDDs, and PCDFs were detected primarily in the vegetation
samples rather than in soil, surface water, or sediment. Due to the extremely complex
nature of vegetative matrices, the identification of these analytes was deemed suspect
and no further significance was attached to their presence. The results were, however,
included in the statistical calculations even though they may have been laboratory
artifacts or false positives (Dames & Moore, 1997a).

2.1.3 Statistical Analysis of Analytical Data. EMBS data were used to establish
comparison criteria for future sampling rounds. For analytes with sufficient data, the
99 percent upper tolerance limit (UTL) was calculated. The 99 percent UTL is the
concentration (within a stated confidence level) below which 99 percent of a population
exists and is often used as a screening criterion in environmental sampling projects.
For analytes where there were not a sufficiently large number of detections to calculate
a UTL, then the maximum detected concentration was designated the comparison
value. Outliers were excluded from the calculations in order to develop a set of
comparison criteria sensitive to very small changes in chemical concentrations.
Nondetects were handled as prescribed in USEPA guidance by replacing nondetects
with values equal to one-half the detection limit.

Using the Shapiro-Wilks method, the data were tested for a normal distribution. If the
data did not fit a normal distribution, they were tested for a lognormal distribution.

2-4
Tables 2.1.3-1 through 2.1.3-5 summarize the comparison criteria and mean
concentrations of analytes detected in each matrix for the baseline study (Dames &
Moore, 1997a) and the 1998 and 1999 (HydroGeoLogic, 2002), and 2002 (PMCD 2003)
follow-on reports.

2.2 1998 EMFS

The first EMFS (1998 EMFS) was conducted in October 1998. Sample locations were
placed as close as possible to those locations sampled during the EMBS. Shrub and
herbaceous vegetation, surface and subsurface soil, surface water, and sediment
samples were collected and analyzed for VOCs, SVOCs, PCBs, PCDDs, PCDFs,
explosives, metals, and anions. Physical characteristics of the shrub and herbaceous
vegetation were also catalogued (HydroGeoLogic, 2002). The analytical results from
the 1998 EMFS were evaluated statistically and compared to the comparison criteria
developed in the EMBS. The mean analyte concentration for each analyte detected in
each medium was compared to the 99 percent UTL developed under the EMBS. If an
analyte detected in the 1998 EMFS had not been detected in the EMBS, then the EMBS
reporting limit was used for comparison. For any parameter with a mean above the
UTL, a point-by-point comparison was performed to determine whether the observed
increase was consistent with what would be expected from the incinerator stack source.
A comparison of group means was made to determine how the differences in means
compared with expected sample variability. Due to contamination in the associated
laboratory method blanks, the PCDD and PCDF data were considered to be suspect
and were not included in the comparison (HydroGeoLogic, 2002).

In general, the surface soil results did not show a significant change from the EMBS.
Cadmium was detected at levels higher than the established comparison criterion in
several locations. The mean cadmium value was 2.2 micrograms per gram (µg/g),
which exceeded the baseline comparison value of 1.7 µg/g. The exceedance is suspect
because the comparison criterion value was very close to the detection limit. In
addition, increased cadmium concentrations were observed across the entire study
area, and were not localized in areas of potential deposition. Deviations from the

2-5
baseline concentrations in soil are probably the result of laboratory variability and soil
heterogeneity (HydroGeoLogic, 2002).

Significant differences were observed for the sediment results. The mean calcium
concentration increased by more than 50 percent, from the baseline value of
64,720 µg/g to 97,920 µg/g. The mean calcium concentration did not, however, exceed
the comparison criterion of 145,251 µg/g. The mean sodium concentration decreased
from the baseline value of 2,036 µg/g to 253 µg/g. The mean concentrations for other
analytes were similar to the mean baseline concentrations (HydroGeoLogic, 2002).

Significant differences also were observed in surface water sample results from
Rainbow Reservoir. The mean sulfate concentration was 11,800 micrograms per liter
(µg/L); no comparison criterion had been established in the baseline study. The mean
concentration of nitrate-nitrite was 692 µg/L, which exceeded the comparison criterion of
545 µg/L. In addition, the mean magnesium concentration was 15,180 µg/L; no
comparison criterion had been established in the baseline study (HydroGeoLogic,
2002).

Rainbow Reservoir had been drained and refilled between the EMBS and the
1998 EMFS. Although it is not possible to quantify what effect this might have had, it is
reasonable to expect that this activity significantly impacted the comparability of the
sediment and surface water results. Consequently, changes in the results for these
media cannot reliably be attributed to impact from operations at TOCDF
(HydroGeoLogic, 2002).

The largest variances were observed for the vegetation results. The shrub vegetation
mean concentrations for barium, boron, calcium, copper, magnesium, manganese,
potassium, sodium, zinc, and sulfate all exceeded the corresponding baseline
comparison criteria. The herbaceous vegetation mean concentrations for boron,
copper, nickel, sodium, and zinc all exceeded the respective baseline comparison
criteria (HydroGeoLogic, 2002).

2-6
The significant differences observed in vegetation results were attributed to seasonal
variability between sampling events; the EMBS was conducted during the month of
May, whereas the 1998 EMFS was completed in October. Vegetation takes up and
stores nutrients in a variable manner on a seasonal basis. The differences in results for
this matrix are not believed to be attributable to activities at TOCDF, especially
considering that soil concentrations (the principal source of plant nutrients) had not
changed significantly (HydroGeoLogic, 2002).

2.3 1999 EMFS

The second EMFS (1999 EMFS) was performed in May 1999. Sample locations were
as close as possible to those for the EMBS and the 1998 EMFS. Shrub vegetation,
herbaceous vegetation, surface soil, subsurface soil, surface water, and sediment
samples were collected and analyzed for VOCs, SVOCs, PCBs, PCDDs, PCDFs,
explosives, metals, and anions. Physical characteristics of the shrub and herbaceous
vegetation also were catalogued (HydroGeoLogic, 2002).

The surface soil results for metals analyses were slightly higher than those obtained for
the EMBS; however, the differences are probably the result of normal variability in soil
composition and laboratory variability. None of the mean surface soil results exceeded
the comparison criteria. Several PCDDs and PCDFs were detected at low levels in the
soil samples. The mean concentrations of the detected compounds ranged from
5.70 nanograms per kilogram (ng/kg) to 21.5 ng/kg. These compounds could also have
been derived from frequent range fires in the area (HydroGeoLogic, 2002).

Sediment and surface water results from Rainbow Reservoir were highly variable when
compared to previous sampling events. Rainbow Reservoir is fed by run-off from Ophir
Canyon and consequently is in a constant state of flux. The periodic draining, refilling,
and stocking of the lake with fish has contributed to this flux. Due to the constant
change of conditions, comparisons of sample results for the sediment and surface water
matrices were determined to be unreliable (HydroGeoLogic, 2002).

2-7
Mean concentrations for calcium, copper, and lead in sediment samples all exceeded
the comparison criteria. PCDDs and PCDFs were detected in the sediment samples at
levels similar to those found in the surface soil samples. One PCDD was detected in
the surface water samples at a mean concentration of 0.00015 µg/L. The mean
nitrate-nitrite concentration of 547 µg/L slightly exceeded the comparison criterion of
545 µg/L (HydroGeoLogic, 2002).

There were several changes noted in the composition of vegetation during the
1999 EMFS. These changes appeared to be the result of invasion by other species, as
well as fire, grazing, and human activities. One site had changed from a sagebrush
prairie to a saline meadow as the result of a berm that had been constructed. None of
the observed changes appeared to be associated with activities at TOCDF
(HydroGeoLogic, 2002).

The mean concentrations of barium, boron, calcium, copper, magnesium, manganese,
potassium, and zinc exceeded comparison criteria for the shrub vegetation. PCDDs
and PCDFs were detected in the shrub vegetation. The PCDDs and PCDFs that had
been detected in the EMBS and assigned comparison criteria were detected at levels
below the respective criteria. Some PCDDs and PCDFs were detected for the first time
(HydroGeoLogic, 2002).

The mean concentrations of boron, chromium, copper, nickel, sodium, zinc, chloride,
and benzyl alcohol exceeded comparison criteria for the herbaceous vegetation, and
PCDDs and PCDFs were detected. The PCDDs and PCDFs that had been detected in
the EMBS and assigned comparison criteria were detected at levels below the
respective criteria. Some PCDDs and PCDFs were detected for the first time
(HydroGeoLogic, 2002).

2.4 2002 EMFS

The third EMFS (2002 EMFS) was performed in May and June of 2002. Two new
soil/vegetation sample locations were added to the 26 locations carried over from

2-8
previous studies. Two new surface water/sediment locations were added as well. In a
departure from previous studies, fish specimens were collected during the 2002 EMFS.
Shrub and herbaceous vegetation, surface soil, subsurface soil, surface water,
sediment samples, and fish specimens were analyzed for VOCs, SVOCs, PCBs,
PCDDs, PCDFs, explosives, metals, and anions. Physical characteristics of shrub and
herbaceous vegetation also were catalogued.

Surface soil results for metals were slightly higher for some compounds and slightly
lower for others when compared with the values obtained for the EMBS; however, the
differences are probably the result of normal variability in soil analyses or normal
laboratory variability. The mean surface soil results for antimony and chloride exceeded
the comparison criteria. Several PCDDs and PCDFs were detected at low levels in the
soil samples. The mean concentrations of the detected compounds ranged from
0.15 ng/kg to 41.1 ng/kg. These compounds could also have been derived from
frequent range fires in the area.

As in 1999, sediment and water results from Rainbow Reservoir were highly variable
and again it was concluded that due to the constant change of conditions, comparisons
of sample results for the sediment and surface water matrices were unreliable.

Mean concentrations for antimony, calcium, lead, chloride, nitrate, and phosphorus in
sediment samples all exceeded the comparison criteria. PCDDs and PCDFs were
detected in the sediment samples at levels similar to those found in the surface soil
samples. Several PCDDs and PCDFs were detected in the surface water samples
ranging from 0.28 picograms per liter (pg/L) to 7.57 pg/L.

There were several changes noted in the composition of vegetation during the interval
between the 1999 EMFS and the 2002 EMFS. These changes appeared to be the
result of an extreme drought, which began in 1999 and became most pronounced
during 2002. The 2002 study identified a decrease in the total number of herbaceous
species. This change does not appear to be associated with activities at TOCDF.

2-9
The mean concentrations of aluminum, barium, boron, calcium, iron, magnesium,
manganese, potassium, sodium, sulfate, and octachlorodibenzo-p-dioxin (OCDD)
exceeded comparison criteria for the shrub vegetation. PCDDs and PCDFs were
detected in the shrub vegetation in the 2002 study that were not detected in previous
studies. The PCDDs and PCDFs detections and concentrations appear to be
increasing in the shrub vegetation.

The mean concentrations of boron, potassium, benzyl alcohol, OCDD, and
octachlorodibenzofuran (OCDF) exceeded comparison criteria for the herbaceous
vegetation. PCDDs and PCDFs were detected at increasing levels in the herbaceous
vegetation. The PCDDs and PCDFs that had been detected in the EMBS and assigned
comparison criteria were detected at levels above the respective criteria.

2-10
Table 2.1.3-1. Summary of Mean Surface Soil Results

Analyte Units
Comparison
Criteriona
1996
EMBS
1998
EMFS
1999
EMFS
2002
EMFS
Detected in EMBS
Aluminum mg/kg 18,646 10,880 12,250 11,022 10,400
Antimony mg/kg 1.40b N/A * 0.87 1.3 2.58
Arsenic mg/kg 12.50 5.80 7.80 7.99 7.22
Barium mg/kg 294 173 166 145 168
Beryllium mg/kg 1.10 0.65 0.63 0.56 0.61
Boron mg/kg 61.3 19.3 18.8 16.0 15.2
Cadmium mg/kg 1.70 0.85 2.20 1.03 * 0.57
Calcium mg/kg 169,508 64,020 61,326 75,596 53,500
Chromium, Total mg/kg 18.4 11.4 13.5 11.2 11.1
Cobalt mg/kg 8.2 4.3 5.8 3.0 4.3
Copper mg/kg 66.9 21.1 22.2 20.2 19.6
Iron mg/kg 18,821 11,200 12,875 10,672 18,800
Lead mg/kg 99.0 31.2 29.3 28.2 29.9
Magnesium mg/kg 19,937 10,877 10,563 10,126 10,100
Manganese mg/kg 1,027 500 503 458 503
Molybdenum mg/kg 5.00 N/A N/A * 0.64 0.26
Nickel mg/kg 33.1 10.4 11.1 9.3 8.5
Potassium mg/kg 7,795 3,998 5,421 4,617 4,080
Sodium mg/kg 869 563 483 241 285
Thallium mg/kg 3.00 N/A 0.32 0.42 * 1.63
Vanadium mg/kg 29.5 17.3 18.4 19.9 13.2
Zinc mg/kg 108.0 58.6 63.1 55.7 58.3
Chloride (as Cl) mg/kg 61.3b N/A 67.3 30.2 78.2
Fluoride mg/kg 6.6b N/A 1.8 1.7 1.6
Nitrogen, Nitrate (as N) mg/kg 12.00b N/A * 1.23 4.05 6.01
Phosphorus, Total (as P) mg/kg 2,064 1,049 R 594 981
Sulfate (as SO4) mg/kg 44.5 N/A 3.0 10.8 10.9
Phenol µg/kg 2,000 N/A NL NL NC
Nitroglycerin µg/kg 8,200 N/A NL NL NC

2-11
Table 2.1.3-1. Summary of Mean Surface Soil Results (Continued)

Analyte Units
Comparison
Criteriona
1996
EMBS
1998
EMFS
1999
EMFS
2002
EMFS
Not Detected in EMBS
Mercury mg/kg NE NL 0.04 0.11 0.02
Selenium mg/kg NE NL 2.60 * 5.77 ND
Silver mg/kg NE NL * 0.35 NL ND
1,1-dichloroethene µg/kg NE NL NL NL 0.99
Benzene µg/kg NE NL NL NL 1.07
Toluene µg/kg NE NL NL 7.0 * 3.95
HPCDF (Total) ng/kg NE NL NL NL * 3.05
HPCDD (Total) ng/kg NE NL NL 8.22 8.72
HXCDF (Total) ng/kg NE NL NL NL * 1.56
HXCDD (Total) ng/kg NE NL NL NL * 1.20
OCDF ng/kg NE NL NL 21.5 5.35
OCDD ng/kg NE NL NL 18.4 41.1
PECDF (Total) ng/kg NE NL NL NL * 0.49
PECDD (Total) ng/kg NE NL NL NL 0.17
Tetrachlorinated
dibenzofurans, (Total) ng/kg NE NL NL 5.7 * 0.29
Tetrachlorinated
dibenzo-p-dioxins ng/kg NE NL NL NL 0.15

Notes:

a The comparison criterion is the EMBS 99 percent upper tolerance limit (UTL) unless otherwise
specified.
b This comparison value is the EMBS maximum detected value because there was insufficient data to
calculate a UTL.

EMBS = Environmental Monitoring Baseline Study
EMFS = Environmental Monitoring Follow-on Study
µg/kg = microgram per kilogram
mg/kg = milligram per kilogram
N/A = not applicable
NC = not calculable
ND = not detected
NE = not established
ng/kg = nanogram per kilogram
NL = not listed in reports
R = results rejected during data validation
* = adjusted mean

2-12
Table 2.1.3-2. Summary of Mean Sediment Data

Analyte Units
Comparison
Criteriona
1996
EMBS
1998
EMFS
1999
EMFS
2002
EMFS
Detected in EMBS
Aluminum mg/kg 22,228 9,260 8,436 8,682 7,750
Antimony mg/kg 0.49b N/A 0.62 * 1.20 3.67
Arsenic mg/kg 22.2 8.0 6.6 6.5 * 6.2
Barium mg/kg 289 172 134 103 142
Beryllium mg/kg 1.40 1.00 0.58 0.47 * 0.86
Boron mg/kg 33.6 20.0 11.2 10.0 14.8
Calcium mg/kg 145,251 64,720 97,920 153,920 200,150
Chromium, Total mg/kg 23.0 8.0 9.0 10.1 10.3
Cobalt mg/kg 5.3 4.0 4.4 2.3 3.1
Copper mg/kg 24.0 8.0 11.2 24.5 14.4
Iron mg/kg 27,661 9,404 9,406 8,084 7,758
Lead mg/kg 18.6 10.0 11.2 46.8 * 21.4
Magnesium mg/kg 30,006 10,946 10,446 9,476 8,897
Manganese mg/kg 785 299 347 175 190
Molybdenum mg/kg 2.0b N/A NL NL 0.4
Nickel mg/kg 27.2 9.0 9.1 9.1 7.8
Potassium mg/kg 7,103 2,560 3,272 2,782 1,849
Sodium mg/kg 8,443 2,036 253 239 * 240
Vanadium mg/kg 47.10 17.00 15.00 * 15.04 11.49
Zinc mg/kg 95.6 37.0 37.8 77.5 51.9
Chloride (as Cl) mg/kg 7.20b N/A 9.40 31.50 * 18.99
Fluoride mg/kg 5.60b N/A * 3.05 3.49 2.89
Nitrogen, Nitrate (as N) mg/kg 2.4 1.0 2.3 N/A 3.6
Phosphorus, Total (as P) mg/kg 1,605 393 R 298 1,622
Not Detected in EMBS
Cadmium mg/kg NE NL 1.60 1.33 0.41
Silver mg/kg NE NL 1.00 * 0.62 ND
Thallium mg/kg NE NL 1.4 NL 1.3
Tin mg/kg NE NL NL NL 0.98
Sulfate (as SO4) mg/kg NE NL 77.20 16.22 4,372

2-13
Table 2.1.3-2. Summary of Mean Sediment Data (Continued)

Analyte Units
Comparison
Criteriona
1996
EMBS
1998
EMFS
1999
EMFS
2002
EMFS
4-Methylphenol (p-cresol) µg/kg NE NL NL 350 324
Benzoic Acid µg/kg NE NL NL NL 261
Total HPCDD ng/kg NE NL NL 71.0 5.3
Total HPCDF ng/kg NE NL NL NL 3.0
Total HXCDD ng/kg NE NL NL NL 0.39
Total HXCDF ng/kg NE NL NL NL 0.33
OCDD ng/kg NE NL NL 15.6 20.0
OCDF ng/kg NE NL NL NL 8.03
Total PECDD ng/kg NE NL NL NL 0.24
Total PECDF ng/kg NE NL NL NL 0.18
Total TCDF ng/kg NE NL NL NL 0.14

Notes:
a The comparison criterion is the EMBS 99 percent upper tolerance limit (UTL) unless otherwise
specified.
b This comparison value is the EMBS maximum detected value as there was insufficient data to
calculate a UTL.

EMBS = Environmental Monitoring Baseline Study
EMFS = Environmental Monitoring Follow-on Study
µg/kg = microgram per kilogram
mg/kg = milligram per kilogram
N/A = Not applicable
ND = Not detected
NE = Not established
ng/kg = nanogram per kilogram
NL = Not listed in reports
R = Results rejected during data validation
* = Adjusted mean

2-14
Table 2.1.3-3. Summary of Mean Water Data

Analyte Units
Comparison
Criteriona
1996
EMBS
1998
EMFS
1999
EMFS
2002
EMFS
Not Detected in EMBS
Aluminum µg/L 670 132 NL 166 155
Boron µg/L 181.0 70.0 ND 33.8 11.3
Calcium µg/L 65,137 60,320 57,520 54,280 47,517
Iron µg/L 373 92 NL 157 * 109
Magnesium µg/L 12,400b N/A 15,180 10,378 10,317
Sodium µg/L 6,051 5,328 5,914 4,788 5,285
Chloride (as Cl) µg/L 6,207 5,800 5,800 4,758 4,745
Nitrogen, Nitrate (as N) µg/L 545 494 692 547 NL
Sulfate (as SO4) µg/L 11,000b N/A 11,800 9,452 10,447
Not Detected in EMBS
Antimony µg/L NE NL NL NL 0.78
Barium µg/L NE NL 21.0 18.4 20.2
Chromium, Total µg/L NE NL NL 4.11 ND
Copper µg/L NE NL NL NL 1.14
Manganese µg/L NE NL NL 6.23 * 4.24
Molybdenum µg/L NE NL NL NL 1.89
Potassium µg/L NE NL NL 430 529
Selenium µg/L NE NL NL 5.4 ND
Thallium µg/L NE NL 8.3 NL ND
Tin µg/L NE NL NL NL 1.16
Zinc µg/L NE NL 18.9 13.4 4.7
Fluoride µg/L NE NL NL 107 NL
Phosphorus, Total (as P) µg/L NE NL NL 19.4 * 23.4
Chloroform µg/L NE NL NL NL 239
HPCDF (Total) ng/L NE NL NL NL 0.31
HXCDD (Total) ng/L NE NL NL NL 0.28
OCDD ng/L NE NL NL 150 7.57
PCDF (Total) ng/L NE NL NL NL 0.42

2-15
Table 2.1.3-3. Summary of Mean Water Data (Continued)

Analyte Units
Comparison
Criteriona
1996
EMBS
1998
EMFS
1999
EMFS
2002
EMFS
Tetrachlorinated dibenzofurans,
(Total)
ng/L NE NL NL NL 0.44

Notes:
a The comparison criterion is the EMBS 99 percent upper tolerance limit (UTL) unless otherwise
specified. b This comparison value is the maximum detected limit because there was insufficient data to calculate
a UTL.

EMBS = Environmental Monitoring Baseline Study
EMFS = Environmental Monitoring Follow-on Study
µg/L = microgram per liter
N/A = not applicable
ND = not detected
NE = not established
ng/L = nanogram per liter
NL = not listed in reports
* = adjusted mean

2-16
Table 2.1.3-4. Summary of Mean Shrub Data

Analyte Units
Comparison
Criteriona
1996
EMBS
1998
EMFS
1999
EMFS
2002
EMFS
Detected in EMBS
Aluminum mg/kg 269 101 * 135 189 393
Barium mg/kg 10.7 6 14.4 12.7 16.8
Boron mg/kg 23.8 14.0 47.5 31.5 26.9
Calcium mg/kg 4,168 2,625 5,278 6,832 7,200
Copper mg/kg 13.8 6.0 16.7 15.6 12.8
Iron mg/kg 228 92 139 222 425
Magnesium mg/kg 1,017 673 1,463 1,450 1,860
Manganese mg/kg 38.0 24.0 52.2 52.5 56.7
Mercury mg/kg 2.50 N/A 0.06 N/A * 0.03
Potassium mg/kg 10,408 7,313 13,510 14,478 15,800
Sodium mg/kg 323 126 922 158 1,330
Tin mg/kg 20.0 N/A 3.4 3.4 * 1.3
Zinc mg/kg 22.6 10.0 37.0 27.7 21.2
PCB-1254 (Arochlor 1254) µg/kg 360 N/A NL N/A NC
Chloride (as Cl) mg/kg 3,495 1,827 2,121 3,423 3,260
Sulfate (as SO4) mg/kg 2,430 N/A 3,326 1,224 16,700
Nitroglycerin µg/kg 43,700,000 N/A NL 20.7 24,600
Tetryl µg/kg 7,000 N/A 2.1 6.2 NC
Octachlorodibenzofuran ng/kg 6.0 N/A R 1.38 * 5.35
Octachlorodibenzo-p-dioxin ng/kg 7.0 N/A R 2.7 70.3
Not Detected in EMBS
Antimony mg/kg NE NL NL NL * 0.88
Arsenic mg/kg NE NL 0.61 0.46 NC
Cadmium mg/kg NE NL 0.97 0.27 0.26
Chromium, total mg/kg NE NL NL 2.9 1.68
Cobalt mg/kg NE NL NL NL 0.054
Lead mg/kg NE NL 1.00 1.25 1.16
Molybdenum mg/kg NE NL 3.20 * 1.24 1.25
Nickel mg/kg NE NL NL 2.31 0.59
Selenium mg/kg NE NL * 0.46 2.49 0.67

2-17
Table 2.1.3-4. Summary of Mean Shrub Data (Continued)
Analyte Units
Comparison
Criteriona
1996
EMBS
1998
EMFS
1999
EMFS
2002
EMFS
Thallium mg/kg NE NL NL NL 0.73
Vanadium mg/kg NE NL NL 0.39 0.96
Nitrogen, Nitrate (as N) mg/kg NE NL NL 32.55 ND
Benzyl alcohol µg/kg NE NL NL * 8,710 * 5,980
2,4,6-Trinitrotoluene µg/kg NE NL NL 8,050 385
2,4-Dinitrotoluene µg/kg NE NL 3,100 5,300 ND
Hexahydro-1,3,5-trinitro-1,3,5-
triazine
µg/kg NE NL NL NL 889
HPCDF (Total) ng/kg NE NL NL 1.45 5.14
HPCDD (Total) ng/kg NE NL NL NL 10.8
HXCDF (Total) ng/kg NE NL NL NL 2.17
Tetrachlorinated
dibenzofurans, (Total)
ng/kg NE NL NL 3.3 ND

Notes:

a The comparison criterion is the EMBS 99 percent upper tolerance limit (UTL) unless otherwise
specified.

EMBS = Environmental Monitoring Baseline Study
EMFS = Environmental Monitoring Follow-on Study
µg/kg = microgram per kilogram
mg/kg = milligram per kilogram
N/A = not applicable
NC = not calculable
ND = not detected
NE = not established
ng/kg = nanogram per kilogram
NL = not listed in reports
R = results rejected during data validation
* = adjusted mean

2-18
Table 2.1.3-5. Summary of Mean Herbaceous Data

Analyte Units
Comparison
Criteriona
1996
EMBS
1998
EMFS
1999
EMFS
2002
EMFS
Not Detected in EMBS
Aluminum mg/kg 4,278 1,360 1,840 1,403 660
Barium mg/kg 67.1 28.0 59.7 43.3 28.0
Boron mg/kg 8.5 7.0 20.0 19.6 13.7
Calcium mg/kg 16,866 5,973 9,461 9,940 5,740
Chromium, Total mg/kg 5.8 2.0 * 1.3 12.0 2.1
Copper mg/kg 12.3 5.0 14.2 10.3 8.7
Iron mg/kg 3,307 1,118 1,773 1,464 699
Magnesium mg/kg 3,261 1,302 2,301 2,167 1,460
Manganese mg/kg 198 84 179 131 77
Molybdenum mg/kg 7.50 N/A 3.80 1.93 1.70
Nickel mg/kg 3.90 N/A 4.90 7.36 0.69
Potassium mg/kg 9,710 3,872 7,907 6,774 13,700
Sodium mg/kg 345 119 1,812 1,339 * 203
Vanadium mg/kg 6.3 2.0 5.5 2.8 6.3
Zinc mg/kg 30.0 15.0 71.0 30.6 23.4
PCB-1254 (Arochlor 1254) µg/kg 800 N/A NL NL NC
Chloride (as Cl) mg/kg 4,654 1,857 2,240 5,427 2,850
Sulfate (as SO4) mg/kg 30,000 N/A 3,334 1,068 347
Benzyl alcohol µg/kg 3,400 N/A 500 5,430 * 3,440
2,4-Dinitrotoluene µg/kg 7,000 N/A NL NL NC
Nitroglycerin µg/kg 438,000 N/A NL 6,260 NC
Octahydro-1,3,5,7-tetranitro-
1,3,5,7-tetrazocine µg/kg 3,700 N/A NL NL * 206
Octachlorodibenzofuran ng/kg 6.50 N/A R * 1.09 * 7.56
Octachlorodibenzo-p-dioxin ng/kg 18.60 N/A R 3.87 81.90
Not Detected in EMBS
Antimony mg/kg NE NL NL 0.91 * 0.84
Arsenic mg/kg NE NL 1.7 * 1.0 0.2
Beryllium mg/kg NE NL NL * 0.064 0.036
Cadmium mg/kg NE NL 1.5 0.4 * 0.1
Cobalt mg/kg NE NL NL 0.73 0.11
Lead mg/kg NE NL 6.4 5.7 2.3
Mercury mg/kg NE NL 0.127 NL 0.029
Selenium mg/kg NE NL 2.30 3.34 0.75
Thallium mg/kg NE NL NL NL 0.51
Tin mg/kg NE NL 2.0 2.8 1.4

2-19
Table 2.1.3-5. Summary of Mean Herbaceous Data (Continued)

Analyte Units
Comparison
Criteriona
1996
EMBS
1998
EMFS
1999
EMFS
2002
EMFS
Bromide mg/kg NE NL NL 161 ND
Nitrogen, Nitrate (as N) mg/kg NE NL NL 24.9 ND
1,2,4-Trichlorobenzene µg/kg NE NL NL 20,800 ND
1,4-Dichlorobenzene µg/kg NE NL NL 20,600 ND
2-Chlorophenol µg/kg NE NL NL 28,800 ND
4-Chloro-3-methylphenol µg/kg NE NL NL 32,400 ND
4-Nitrophenol µg/kg NE NL NL 37,000 ND
Acenaphthene µg/kg NE NL NL 21,300 ND
Benzoic acid µg/kg NE NL NL 34,600 * 7,920
N-Nitrosodi-n-propylamine µg/kg NE NL NL 26,700 ND
Pentachlorophenol µg/kg NE NL NL 43,000 ND
Phenol µg/kg NE NL NL 31,600 ND
Pyrene µg/kg NE NL NL 14,000 ND
Hexahydro-1,3,5-trinitro-1,3,5-
triazine µg/kg NE NL NL 1,000 ND
Tetryl µg/kg NE NL NL 1,450 ND
HPCDF (total) ng/kg NE NL NL NL 4.35
HPCDD (total) ng/kg NE NL NL * 1.09 9.17
PECDF (total) ng/kg NE NL NL NL 0.43
Tetrachlorinated dibenzofurans,
(Total) ng/kg NE NL NL 0.42 ND

Notes:
a The comparison criterion is the EMBS 99 percent upper tolerance limit (UTL) unless otherwise
specified.

EMBS = Environmental Monitoring Baseline Study
EMFS = Environmental Monitoring Follow-on Study
µg/kg = microgram per kilogram
mg/kg = milligram per kilogram
N/A = not applicable
NC = not calculable
ND = not detected
NE = not established
ng/kg = nanogram per kilogram
NL = not listed in reports
R = results rejected during data validation
* = adjusted mean

2-20
(This page intentionally left blank.)

3-1
SECTION 3
ENVIRONMENTAL SETTING

Tooele County covers 17,930 square kilometers (km) (6,923 square miles), and the
Tooele-Rush Valley sub-basin is approximately 3,112 square km (1,202 square miles).
DCD covers 78.4 square km (19,364 acres) and is located approximately 88 km
(55 miles) southwest of Salt Lake City in the southern (Rush Valley) portion of the
sub-basin.

The 2002 EMFS report (PMCD, 2003) contains an extensive literature review pertaining
to the TOCDF environmental setting including: geology, topography, seismic activity,
hydrology, soil, vegetation, air quality, meteorology, land use, and fire history. The
following paragraphs provide only updated information relevant to interpretation of the
2005 EMFS data and TOCDF environmental data as a whole.

3.1 Air Quality

In 1996, air dispersion modeling was used to designate areas of potential high, medium,
and low deposition for emissions from the TOCDF stack. The air dispersion model for
particulate stack emissions from TOCDF is shown in figure 3.1-1. Based on a
recommendation of the 2002 EMFS report, new air modeling was performed in 2004 to
incorporate advances in air modeling techniques and differences between the 1996 air
model and modeling performed by the State of Utah as part of the Health Risk
Assessment. The 2004 model results (contained in appendix B to the Field Sampling
Plan [FSP]) agreed with the earlier results. For this 2005 EMFS Report, the air
modeling map from 1996 is retained to ensure comparability with earlier efforts and to
maintain the prior zone classification for all sites.

3-2
3.2 Precipitation

Normal annual precipitation at DCD is about 28 centimeters (cm) (11.02 inches), which
includes about 100 cm (39.3 inches) of snow, and is distributed fairly evenly throughout
the year. More precipitation falls on the mountainous regions, especially as snow.
Snow is extremely important to the Rush Valley water supply because it functions as a
storage reservoir, releasing water into streams and aquifers as temperatures rise.

The nearest National Oceanic and Atmospheric Administration (NOAA) reporting site is
in Tooele, Utah. The average annual precipitation at Tooele, Utah, is 17.57 inches,
slightly higher than at DCD. Annual precipitation at Tooele, Utah, for years 1995
through present is shown in the following list based on data from the NOAA Western
Regional Climate Center at the Desert Research Institute in Reno, Nevada:

• 1995 – 24.34 inches

• 1996 – 21.44 inches

• 1997 – 26.74 inches

• 1998 – 26.69 inches

• 1999 – 15.95 inches

• 2000 – 18.46 inches

• 2001 – 17.35 inches

• 2002 – 13.60 inches

• 2003 – 15.49 inches

3-3
• 2004 – 17.77 inches

• 2005 – 18.75 inches through 22 July.

Tooele, like most of Utah, experienced drought conditions from 1999 though 2004. The
year 2002 was considered an “extreme drought” on the Palmer Drought Severity Index.
The 2004-2005 water year (which runs from October 1 to September 30) was the first
water year to be above normal in the last 6 years (National Weather Service, Salt Lake
City, Utah).

3.3 Population

In the year 2000, the population of Tooele County was 40,735 according to the United
States census, and is projected to be 45,864 in 2005 according to the Tooele County
Chamber of Commerce internet Web page, Demographics (TCCC, 2005).

In the region near TOCDF, 70 percent of the population lives in either Tooele, a city of
25,225 people, or Grantsville, a village of 6,772. Both 2005 population estimates are
according to the Tooele County Chamber of Commerce internet Web page,
Demographics (TCCC, 2005). The remaining 30 percent live in the small towns, of
which Stockton, Rush Valley, and Ophir are the closest to DCD. These towns are within
a 15-mile radius of TOCDF. The population of Rush Valley increased from 400 in
1990 to 1,893 in 2000.

3.4 Local Fire History

Fire has a profound effect on the environment, both directly through destruction of
vegetation and indirectly through the release of chemical substances such as dioxins,
furans, SVOCs, VOCs, carbon dioxide (CO2), carbon monoxide (CO), nitrogen, and
phosphorus into the soil and air. Range fires are frequent in Rush Valley as planned,
accidental, or naturally occurring fires. The products of combustion from these fires,

3-4
and their distribution over the area, are of interest because of the potential impacts to
soil and human and ecological receptors. The locations of soil sampling points,
prevailing wind conditions associated with these fire locations, and times are relevant
parameters for evaluating the impacts of these fires on the local environment.

The U.S. Bureau of Land Management (USBLM) and DCD maintain fire occurrence
records and have provided data for fires occurring between May 1996 and
December 2004. During that period, a total of 204 fires were observed in the
TOCDF-Rush Valley area. A summary of the USBLM fire data is provided in
table 3.4-1. A map showing the distributions of fires reported in the Rush Valley area
between 1996 and 2001 is provided in figure 3.4-1. Because the degree of effect on the
environment is directly related to the size of the fire, it is useful to quantify the temporal
and spatial distributions of fires in this area. A total of 185 of the 204 fires
(90.6 percent) covered areas less than 100 acres. Of the remaining 19 fires, 6 covered
areas from 100 to 300 acres, 6 covered 301 to 999 acres, 3 covered 1,000 to
2,999 acres, 1 covered 3,000 to 4,999 acres, 2 covered 5,000 to 9,999 acres, and
1 exceeded 10,000 acres (USBLM, 2004). The locations of individual fires are shown
as points, keyed to the legend according to acreage involved in the fire.

The 4 largest fires are summarized as follows:

• Topliff 20 July 1998 13,926 acres (21.76 square miles)

• Faust 03 July 1998 6,550 acres (10.23 square miles)

• Camp Floyd 01 August 1996 5,542 acres (8.66 square miles)

• Rush 02 July 1999 4,101 acres (6.41 square miles).

The distribution of fires of various size-range classes, combined with prevailing wind
data, provides a qualitative depiction of potential impacts of post-1996 fires on the local

3-5
environment. Prevailing winds at DCD are from the south-southeast, with occasional
winds from the north-northwest. Wind direction follows the long axis of Rush Valley and
is controlled by the surrounding mountains. Note that the three largest fires occurred in
1996 and 1998 and were located southeast of DCD, upwind of the TOCDF stack.
Additional fires exceeding 100 acres in size occurred near the DCD boundary during the
years 1997 through 1999. These fires were in close proximity to sampling locations and
may have influenced sample site soil and vegetation. No significant fires have occurred
near any of the sampling points since 2001.

3-6
Table 3.4-1. Range Fires in Rush Valley 1996 through 2004

Year Month Day Acres Name Latitude Longitude
2004 6 13 11.0 SR 73 MM 19&23 40.2509 -112.1688
2004 7 7 2.0 Wells Cyn 40.2588 -112.1351
2004 7 7 1.5 SKEET 40.2586 -112.1341
2004 3 24 0.1 Mercur 40.3036 -112.2467
2004 4 6 0.1 County Lin 40.2353 -112.1686
2004 4 21 0.1 BIG HOLLOW 40.3500 -112.5333
2004 4 28 0.1 INDIAN MT 40.3982 -112.5241
2004 4 28 0.1 RUSH 40.3978 -112.5258
2004 6 12 0.1 BAUER 40.4697 -112.3622
2004 6 19 0.1 5 MI WASH 40.2404 -112.1544
2004 6 26 0.1 SR73 MM17 40.2394 -112.1595
2004 7 14 0.1 South Mtn 40.4453 -112.4147
2004 7 31 0.1 Pass 40.2424 -112.1467
2004 9 1 0.1 SR 73 MM 16 40.2499 -112.1885
2004 9 12 0.1 MITCHELL CANYON 40.3469 -112.2350
2003 7 18 247.0 Sunshine 40.2603 -112.2292
2003 7 24 242.0 Bauer 40.4631 -112.3531
2003 7 27 42.0 Aquaduct 40.1717 -112.5108
2003 7 28 8.0 Stukey 40.2350 -112.4833
2003 7 31 2.0 Pole Cyn 40.3456 -112.1269
2003 6 17 1.0 NORTH RUSH VALLEY 40.3800 -112.5300
2003 7 7 1.0 Rail 40.3153 -112.4039
2003 6 18 0.5 Faust 1 40.2083 -112.5169
2003 7 23 0.5 Border 40.2658 -112.2069
2003 7 18 0.3 Little Mtn 40.1922 -112.5147
2003 8 29 0.3 Little 40.1664 -112.5194
2003 6 18 0.1 Faust 2 40.1961 -112.4953
2003 6 18 0.1 Faust 3 40.2014 -112.5181
2003 6 18 0.1 Faust 4 40.2253 -112.5328
2003 7 20 0.1 eagle 40.2992 -112.2231
2003 7 20 0.1 West Dip 40.3256 -112.2519
2003 7 20 0.1 BENNION CANYON 40.3300 -112.2400
2003 7 23 0.1 RockCyn 40.1486 -112.5142
2003 7 24 0.1 Wells Cany 40.2658 -112.1994
2003 7 28 0.1 Clover 40.3153 -112.5125
2003 8 14 0.1 Calumet 40.4436 -112.3311
2003 8 14 0.1 Ophir 40.3744 -112.2756
2003 8 14 0.1 SOLDIER 40.4300 -112.3400
2003 8 15 0.1 Dry Crk 40.4517 -112.2944
2003 8 18 0.1 4 SR199 8 18 40.2400 -112.1900
2003 8 21 0.1 Wellshine 40.2772 -112.2056
2003 8 23 0.1 Five 40.2281 -112.1794
2003 8 23 0.1 5MI CAR 40.2200 -112.1600
2003 8 29 0.1 WELCH 40.4058 -112.5036

3-7
Table 3.4-1. Range Fires in Rush Valley 1996 through 2004 (Continued)

Year Month Day Acres Name Latitude Longitude
2003 8 29 0.1 GOVT CREEK 40.4000 -112.4700
2002 10 17 7.0 Segars 40.3694 -112.4394
2002 7 4 0.1 Five Mile 40.2272 -112.1778
2002 8 19 0.1 E Johnson 40.3836 -112.4669
2002 8 19 0.1 E South Mt 40.4642 -112.4325
2002 8 19 0.1 Ophir 40.3547 -112.2783
2002 8 19 0.1 W South Mt 40.4678 -112.4567
2002 9 5 0.1 Manning 40.2978 -112.1528
2002 9 7 0.1 Silcox 40.4706 -112.2972
2001 9 28 720.0 Rush Lake 40.4064 -112.4597
2001 7 26 183.0 Fairfield 40.2669 -112.2214
2001 6 17 15.0 Atherly La 40.1981 -112.4139
2001 9 22 10.0 Stockton 6 40.3500 -112.3017
2001 8 7 1.5 7 Mile 40.2108 -112.1842
2001 6 24 0.5 SOUTH MOUNTAIN 40.4700 -112.3900
2001 5 29 0.3 Hell Hole 40.2475 -112.5381
2001 6 24 0.3 Mitchell 40.3061 -112.2283
2001 6 24 0.3 Stockton 40.4614 -112.3831
2001 5 28 0.1 TWO SPRINGS 40.2300 -112.5000
2001 6 22 0.1 TIRE FIRE 40.1500 -112.2000
2001 6 28 0.1 Radio Towe 40.1556 -112.3681
2001 7 13 0.1 SouthMt 2 40.4667 -112.4667
2001 7 26 0.1 Big Spring 40.2742 -112.1500
2001 7 26 0.1 Manning 40.2917 -112.1536
2001 7 26 0.1 Wells Cany 40.2672 -112.1719
2001 8 7 0.1 Clover 40.2458 -112.4831
2001 8 7 0.1 Kimball 40.2244 -112.1458
2001 8 7 0.1 Thorp Hill 40.1847 -112.1772
2001 8 7 0.1 Toplift 40.1778 -112.1628
2001 8 7 0.1 4 LEAF 40.3200 -112.5000
2001 8 23 0.1 Rocky Cyn 40.1556 -112.5431
2001 8 29 0.1 Highway 73 40.3619 -112.3342
2001 9 2 0.1 Two Spring 40.2425 -112.4778
2001 9 19 0.1 Mercur Cyn 40.3139 -112.2381
2001 10 20 0.0 5 MILE 40.2300 -112.1600
2000 8 6 2,379.0 CowHollow 40.3886 -112.5064
2000 6 15 84.0 StocktonPa 40.4650 -112.3442
2000 6 21 8.3 StJohn 40.3664 -112.4872
2000 8 7 2.0 Faust 40.1864 -112.4883
2000 8 19 2.0 Sunshine 40.2978 -112.2136
2000 6 18 1.0 MANNING 1 40.2900 -112.1400
2000 7 28 1.0 Union 40.4350 -112.3767
2000 9 1 1.0 MANNING CAMPFIRE 40.2800 -112.1600
2000 6 25 0.5 MANNING 11 40.3100 -112.1400

3-8
Table 3.4-1. Range Fires in Rush Valley 1996 through 2004 (Continued)

Year Month Day Acres Name Latitude Longitude
2000 8 4 0.3 Water Tank 40.2372 -112.5114
2000 8 5 0.3 WATER TANK 40.2200 -112.5200
2000 6 18 0.2 ManningCn3 40.2969 -112.1647
2000 6 18 0.1 FaustCreek 40.1814 -112.5217
2000 6 18 0.1 Manning 2 40.2992 -112.1481
2000 6 18 0.1 ManningCn1 40.2969 -112.1458
2000 6 24 0.1 DryCanyon 40.3750 -112.3261
2000 6 25 0.1 Manning 10 40.3114 -112.1647
2000 7 7 0.1 JOHNSON FIRE 40.3300 -112.4600
2000 7 10 0.1 Faust 2 40.1692 -112.5153
2000 8 3 0.1 Onaqui 40.2203 -112.5033
2000 8 4 0.1 Hide Seek 40.2331 -112.5258
2000 8 15 0.1 Mercur 40.3100 -112.2619
2000 8 18 0.1 Trujillo 40.1956 -112.5053
2000 8 18 0.1 EAST FAUST CREEK 40.2000 -112.5000
2000 8 22 0.1 MitchellCa 40.2969 -112.2214
2000 8 23 0.1 ChurchRoad 40.3692 -112.4672
2000 8 28 0.1 DC 40.2769 -112.2492
2000 9 2 0.1 Aqueduct 40.1811 -112.5053
2000 9 2 0.1 SCALLY WRONGLER 40.3000 -112.1400
2000 9 8 0.1 PROSPECT 40.2200 -112.1400
2000 9 21 0.1 Silverado 40.3547 -112.2972
1999 7 2 4,101.0 Rush 40.4561 -112.4194
1999 7 11 1,909.2 HWY 36 40.2606 -112.3969
1999 7 7 364.0 Clover 40.2453 -112.4383
1999 9 11 228.0 Monument 40.1833 -112.3139
1999 7 5 34.0 Stockton 40.4644 -112.3397
1999 5 4 23.0 AJAX 40.2500 -112.3900
1999 7 2 15.0 South Mtn 40.4656 -112.4122
1999 7 24 10.0 Pennys 40.3778 -112.3850
1999 7 27 4.0 Jeep Trail 40.1636 -112.5325
1999 6 29 2.0 Stockton P 40.4514 -112.3647
1999 7 6 2.0 MITCHEL CANYON 40.3500 -112.2600
1999 6 20 1.5 Rocket 40.2067 -112.1919
1999 7 4 1.0 SUNSHINE FIRE 40.3100 -112.2000
1999 7 24 1.0 CloverCk 40.3333 -112.4833
1999 7 24 1.0 Suntan 40.3725 -112.4222
1999 8 9 1.0 PVC FIRE 40.3300 -112.4300
1999 8 9 1.0 PVC 40.3294 -112.4581
1999 9 12 1.0 Sand Pit 40.3561 -112.3067
1999 7 6 0.5 MITCHELL 40.2922 -112.2594
1999 7 26 0.5 Ophir Cyn 40.3517 -112.3036
1999 10 26 0.5 RV FIRE 40.3500 -112.3700

3-9
Table 3.4-1. Range Fires in Rush Valley 1996 through 2004 (Continued)

Year Month Day Acres Name Latitude Longitude
1999 6 21 0.3 LITTLE MTN 40.1411 -112.5406
1999 3 20 0.1 R.V. 40.2300 -112.1600
1999 6 16 0.1 E Onaqui 40.2206 -112.4669
1999 6 16 0.1 Faust Crk 40.1833 -112.4833
1999 7 9 0.1 TwoSprings 40.1869 -112.4972
1999 8 19 0.1 WATER TANK 40.1994 -112.5039
1999 8 20 0.1 GraniteWas 40.1994 -112.5044
1999 8 25 0.1 E Hickman 40.4197 -112.4914
1998 7 20 13,926.0 TOPLIFF 40.1817 -112.2581
1998 7 3 6,550.0 FAUST 40.2200 -112.2481
1998 7 4 680.0 BEACON 40.1978 -112.3181
1998 7 21 130.0 SO.DEPOT 40.3075 -112.2783
1998 7 19 58.6 DRY CANYON 40.4078 -112.3333
1998 6 28 30.0 5MILEPASS 40.2389 -112.1681
1998 8 14 15.0 GILSONITE DRAW 40.2500 -112.2700
1998 7 6 4.0 FAUSTCREEK 40.1736 -112.4775
1998 7 20 3.0 MILL CYN 40.3339 -112.2344
1998 8 23 2.0 STOCKTON 40.4531 -112.3483
1998 9 7 2.0 FAUSTCRK 40.2186 -112.4172
1998 7 19 1.0 JUNCTION73 40.2178 -112.1897
1998 7 20 1.0 ROCKY CYN 40.1667 -112.5350
1998 8 8 1.0 HICKMAN 40.4231 -112.4694
1998 8 24 1.0 RAILROAD 40.1653 -112.3817
1998 7 21 0.7 BALDMTN 40.4081 -112.3436
1998 6 20 0.5 POKERKNOLL 40.1864 -112.1939
1998 9 3 0.2 CLOVERSIDE 40.3194 -112.4069
1998 7 20 0.1 HELLHOLE 40.2342 -112.5350
1998 7 20 0.1 MERCUR CYN 40.3333 -112.2833
1998 10 13 0.1 RUSSELL 40.4364 -112.4958
1998 6 25 0.0 ROLLOVER 40.3800 -112.3100
1997 6 29 1,337.0 RR #1 40.2381 -112.3906
1997 9 11 696.0 PENNY'S 40.3667 -112.3533
1997 7 15 600.0 SOUTH AREA 40.3353 -112.3331
1997 8 23 300.0 ST. JOHN 40.3428 -112.3542
1997 7 8 60.0 TWO SPRING 40.2292 -112.4969
1997 8 3 15.0 BOX CANYON 40.3533 -112.4117
1997 7 27 10.0 HICKMAN FIRE 40.4200 -112.5400
1997 7 27 10.0 E. HICKMAN 40.4267 -112.5433
1997 8 28 10.0 VERNON HIL 40.1617 -112.3789
1997 9 11 5.0 WELL 40.2528 -112.2308
1997 6 21 3.0 S. BARLOW 40.1983 -112.1600
1997 7 27 2.0 FAUST CREE 40.2250 -112.4867
1997 8 1 2.0 WELCH CNY 40.4233 -112.4928
1997 7 31 1.0 FAUST #2 40.2208 -112.4858

3-10
Table 3.4-1. Range Fires in Rush Valley 1996 through 2004 (Continued)

Year Month Day Acres Name Latitude Longitude
1997 7 27 0.5 LEE CANYON 40.2900 -112.5361
1997 6 15 0.3 WEST DIP FIRE 40.4100 -112.1400
1997 6 18 0.3 DUMP RD FIRE 40.2300 -112.5200
1997 6 19 0.3 BOX ELDER WASH 40.4600 -112.3900
1997 6 29 0.3 BAYER DUMPFIRE 40.4600 -112.3500
1997 7 31 0.1 BIG CANYON 40.2606 -112.4942
1997 8 23 0.1 CHERRY 40.2967 -112.5233
1997 8 23 0.1 LITTLE MTN 40.1436 -112.5431
1997 9 7 0.1 HELLHOLE 40.2597 -112.4992
1996 8 1 5,542.0 CAMP FLOYD 40.2167 -112.2500
1996 8 18 400.0 UTS #19 40.3500 -112.4833
1996 9 1 50.0 TOPLIFF 40.1500 -112.1667
1996 8 10 10.0 Hogan Fire 40.4200 -112.4100
1996 8 10 10.0 UTS #17 40.4000 -112.4333
1996 7 7 5.0 WELLS CYN 40.2500 -112.1500
1996 8 18 5.0 BIG CYN 40.2500 -112.4833
1996 7 6 3.0 THORPEHILL 40.2333 -112.1525
1996 6 11 1.5 CLOUD BRST 40.3333 -112.2500
1996 8 3 1.0 GRAVEL PIT 40.2167 -112.2000
1996 7 18 0.5 FAUST CRK 40.2100 -112.4867
1996 6 7 0.3 UTS #2 40.3333 -112.1500
1996 7 16 0.3 Little Sod Fire 40.4400 -112.3700
1996 8 8 0.3 Merkur Canyon 40.3100 -112.2300
1996 8 16 0.3 Big Canyon 40.2600 -112.4800
1996 8 25 0.3 Stockton Gravel 40.4600 -112.3500
1996 6 7 0.1 Sunshine Canyon 40.2600 -112.1800
1996 7 3 0.1 TWOSPRNGS 40.2556 -112.5278
1996 8 1 0.1 Single Tree Lightning 40.2800 -112.2200
1996 9 10 0.1 UTS #24 40.3000 -112.1500

3-11
Figure 3.1-1. Common Stack Air Dispersion Model

3-12
Figure 3.4-1. Range/Forest Fire

4-1
SECTION 4
STUDY METHODOLOGY

This section describes deviations from the approved project plans, issues identified in
the data from previous reports, and other pertinent evaluation procedures not clearly
defined in the plans. Except where noted in the following paragraphs, all activities were
conducted in accordance with the approved plans. These activities include all aspects
of field sampling, laboratory analysis, data validation, data evaluation, statistical
analysis, and reporting.

4.1 Sample Locations

The FSP described 43 sample sites that were to be located and sampled. Twenty-eight
of the locations were retained from previous sampling rounds and 15 were new
locations to be sampled for the first time in 2005. A map depicting all sample locations
is provided in figure 4.1-1. Surface water and sediment sample locations associated
with Rainbow Reservoir are shown in figure 4.1-2.

4.1.1 Sample Locations Retained from Previous Studies. All 28 surface soil and
vegetation characterization sites from the 2002 EMFS were to be included in the
2005 EMFS. Sites were located based on previously reported latitude/longitude
coordinates and verified in the field by locating the permanent markers established
during previous sampling events. All but 2 of the 28 prior locations were sampled (see
paragraph 4.1.3.1). The sampling site in Ophir Canyon was also retained from the
2002 EMFS as was the sampling of Rainbow Reservoir, though the number of samples
collected from the reservoir was decreased in 2005 compared to previous sampling
rounds (see paragraph 4.1.3.2).

4.1.2 Sample Locations Added for the 2005 EMFS. Fifteen new soil/vegetation
sample locations were added to the study and the number of surface water/sediment

4-2
samples collected from Rainbow Reservoir, were reduced from five locations to two
locations.

4.1.2.1 Soil and Vegetation Sample Locations. The 15 new soil/vegetation sample
locations added for the 2005 sampling season were distributed across the three
potential deposition zones, as defined by air modeling, both north and south of TOCDF.
Theses new sites were added to provide additional control for contaminant distribution
contouring.

The new sites were initially located on a topographic map. Then, to establish the new
sample stations, the field team evaluated features in the vicinity of the extrapolated grid
coordinates. Consideration was given to avoiding locations for soil and vegetation
sampling sheltered by landscape or manmade features, those within 20 meters of a
roadway or railroad, those currently used as agricultural or grazing land, or those near
open burning/detonation areas within the boundaries of DCD. If the pre-selected
sample location fell into one of these areas, the field team leader selected the closest
appropriate location for establishing a sample station. Selection of the replacement
sampling station was accomplished in coordination with the TOCDF Field Office and the
Utah DEQ. The coordinates for the selected sample locations are presented in
section 6 of this report.

4.1.2.2 Water/Sediment Sample Locations. The 2005 FSP called for a new sampling
location to be added where water from Ophir Canyon discharges into Rainbow
Reservoir. This sample was not collected, for reasons described in paragraph 4.1.3.2.

4.1.3 Sample Location Deviations. As situations arose that required a deviation from
the FSP, the course of action selected was coordinated between the field team, the
TOCDF Field Office, and the Utah DEQ before being implemented.

4.1.3.1 Soil/Vegetation Sample Locations. Locations 0112 and 0224, sampling sites
retained from previous sampling rounds, were not sampled in the 2005 EMFS because
access was denied by the land owners. A replacement location was selected for 0112,

4-3
one-half mile south of the original location. No replacement was made for 0224, due to
lack of public property within 3 or 4 miles of the original location. During 2005, several
sample station markers from previous rounds were not found at the designated
coordinates presented in the FSP. For these sites, if the permanent sample station
monuments were not located within a one-hundred meter search centered around the
coordinates provided, the field team concluded that the missing monuments had been
removed since the 2002 EMFS field event. Two sample locations (0400 and 1222)
were missing station monuments. The locations were re-established by positioning a
white and orange painted steel fence post at the FSP coordinates. Additionally, as with
all the other locations, 2-foot wooden stakes were placed at all soil sampling locations.

The new location established south of 0112 was sampled and characterized using
0112 as the sample nomenclature. During data evaluation, the location identification
(ID) was changed to 0111 to more accurately reflect the new location and to prevent
vegetation characterization comparisons with sample station 0112, since the vegetation
at the two sites had noticeable differences. The sample IDs for the chemical analysis
for surface soil and vegetation have retained the 0112 location designation.

4.1.3.2 Water/Sediment Sample Locations. The FSP called for a sample to be
collected where water from Ophir Canyon discharges into Rainbow Reservoir. That
sample was planned to be collected from a manhole adjacent to Rainbow Reservoir;
however, the discharge lines inside the vault were hard-piped and did not allow for
samples to be collected. This sample will be dropped from future FSPs.

4.1.4 Sample Collection Schedule. Sample collection was planned for May 2005 to
obtain data comparable to the EMBS. Samples were collected from 38 of 43 planned
sites between 10 May and 20 May 2005. Access to five locations (0112, 0308, 0623,
and 0819) was not possible in May 2005 because right-of-entry documents were not
completed in time. Soil and vegetation samples were collected at these locations
between 21 June and 23 June 2005.

4-4
4.2 Sample Media

The follow-on sampling program involved collection of surface soil, vegetation, surface
water, and sediment. Subsurface soil represents the only media not sampled that was
included as one of the originally selected media for the baseline sampling program and
continued through the previous EMFS sampling events.

4.2.1 Soil. Surface soil (to a depth of 1 cm) samples were collected in accordance
with the project plans. Samples were collected from three separate locations and
composite into one sample. Sampling was conducted in the sector designated in the
work plan, from areas not previously sampled during prior rounds. No deviations were
required and no technical issues were identified.

4.2.2 Vegetation. In accordance with the project plans, two types of vegetation (shrub
and herbaceous) were sampled. Shrub sampling involved collection of shoots from the
big sagebrush (Artemisia tridentata). This species was selected in the EMBS because it
is widely distributed in the area and is the dominant shrub at most sites. At some sites,
the Utah juniper (Juniperus osteosperma) was sampled due to the absence of suitable
specimens of sagebrush.

Sampling of herbaceous vegetation involved the collection of grass type plants for
analyses. During the 2005 EMFS, sufficient herbaceous material was present to collect
sample aliquots from only one species and from the designated sector only. The
dominant species at each location was selected for sample collection. The roots were
not included in the vegetation samples; only the aboveground stalks were collected for
analysis.

4.2.3 Surface Water and Sediment. Surface water and sediment samples were
collected from Rainbow Reservoir, located northeast of the TOCDF common stack, and
from Ophir Creek, the water source for the reservoir (figure 4.1-2). Reservoir overflow
water currently goes to an off-depot wetlands area. The reservoir is manmade, covers
approximately 1.4 hectares (3.5 acres), and has a maximum depth of approximately

4-5
6 meters (20 feet). Water from Ophir Creek is directed via underground pipe from Ophir
Creek to supply the reservoir. Two surface water samples collocated with two sediment
samples were collected from near-shore locations of Rainbow Reservoir. The sample
sites were located around the perimeter of the reservoir, avoiding inflow and outflow
locations.

One water and collocated sediment sample was collected from Ophir Creek near where
the water enters the diversion pipe that feeds the reservoir.

4.3 Numbers of Samples

The scoped follow-on sampling program consisted of collecting 43 surface soil,
43 herbaceous vegetation, 43 shrub vegetation, 4 surface water, and 4 sediment
samples. Due to the absence of shrub vegetation at stations 0707 and 1706 and since
location 0224 was not accessed, only 40 shrub vegetation samples were collected.
Only 42 surface soil and herbaceous samples were collected because access was not
obtained for station 0224. As discussed previously, the planned water and sediment
samples from the discharge pipe near Rainbow Reservoir were not collected, resulting
in only 3 surface water and 3 sediment samples collected out of 4 specified in the FSP.

4.4 Sampling and Analytical Parameters

Table 4.4-1 lists the analytical parameters for soil, vegetation, surface water, and
sediment samples. A complete list of the USEPA Test Methods for Evaluating Solid
Waste (SW-846) performed for this study is provided in the approved Quality Assurance
Project Plan (QAPjP). There were no deviations from the proposed laboratory analytical
plan for any media.

In addition to sampling for chemical analysis, physical characterization was conducted
at each sample station. Physical characterization such as soil texture, grazing
evidence, and vegetation will be used for inter-sample station and inter-year
comparisons. Vegetation characterization allows for the detection of changes in

4-6
community composition, comparison with reference areas, and comparison with other
installations. Because certain species are more sensitive to the presence of increased
levels of certain analytes, physical characterization allows observation of any changes
in plant community composition, including potential impacts from particulate deposition
effects.

4.5 Statistical Analysis

The chemical analytical results obtained for soil and vegetation were subjected to
statistical analysis in accordance with the project plans. For soil and vegetative
statistics, no deviations were required and no technical issues were identified in
previous studies. All chemical data for both soil and vegetative samples were
statistically evaluated in accordance with the project plans as indicated in FSP
Figures 6-1 and 6-2. Paired-sample statistical methods were evaluated along with the
previously used random-sample statistical methods for the laboratory analytical results.
The use of relative percent difference (RPD) calculations to compare mean
concentrations has been used in previous studies. These RPD calculations have been
discontinued per concurrence with the Utah DEQ and will not be used in this study.

Physical characteristics of each sample station were recorded in the field as prescribed
in project plans. Physical characteristics of each site are presented in section 6 in a
manner comparable to previous studies.

Vegetation characterization data were summarized in the manner prescribed in the
FSP. It was noted in preparation of vegetation summary data that two equations were
missing from the FSP and that the equation for species diversity, while not incorrect,
was not the best method for expressing diversity. The following paragraphs describe
vegetation characterization data, including the new equations.

4-7
4.5.1 Vegetative Characterization. Details regarding sample stations, shrub plot and
herb plot setup, and sampling procedures may be found in the FSP. Vegetative
characteristics recorded in the field consisted of the following information:

• Individual species identification

• Individual clump/plant counts

• Percent cover

• Height (shrubs only)

• Diameter (shrubs only).

4.5.2 Shrub Layer. As part of this sampling event, a designated shrub plot coinciding
with the previous EMBS and EMFSs was established at the previously established
sample stations. Sample station 0224 was not accessed during the 2005 sampling
event. Sample station 0112 was moved approximately one-half mile south and
established as new sample station 0111. New shrub plots were established at
0111 and the 15 new sample stations. The shrub plot for which the vegetative and
herbaceous characteristics were evaluated was a 22.5° (1/16) sector of the sample
station, or approximately 177 square meters. During the baseline sampling event, the
dominant shrub encountered was big sagebrush (Artemisia tridentata). This species
reproduces from the center out, leaving a ring of genetically identical stems. Because
of its growth pattern, one clump of stems is defined as one genetic individual. For all
other species encountered, a clump was defined as one individual. These definitions
have been used for the follow-on sampling events to maintain consistency.

During preparation of the vegetation summary data, it was discovered that the equation
used for assessing forage value had not been recorded in the FSP. Therefore, the
equation for forage value is recorded here. It was also noted that the equation for

4-8
species diversity index presented in the FSP was not the one best suited for that
statistic; therefore, that equation is also presented here.

4.5.2.1 Forage Value Index. Forage value index is a measure of rangeland quality.

Individual species were assigned forage values (see table 4.5.2.1-1) based on
information provided in Parker (1979), Vallentine (no date), Hitchcock (1950),
Stubbendieck et al. (1992), and Whitson et al. (1992). Species for which no information
was found were considered to have poor forage value.

Forage value index was calculated by first multiplying the importance value of each
species by its forage status. These products were then summed and divided by the
sum of the species importance values. The higher the forage value index, the lower the
quality of the rangeland.

where
FVI = forage value index
SIV = importance value per species
SFV = forage value per species.

4.5.2.2 Species Diversity. The equation for species diversity recorded in the FSP and
the 2002 EMFS report is one of two equations developed by E. H. Simpson in the 1940s
(Simpson, 1949). The equation in the FSP yields the probability (Simpson called it “D”)
that two randomly selected individuals will belong to the same species. While that is a
useful concept, the result, as a measure of diversity, is counter intuitive in that as
diversity increases, the value of D decreases. Therefore, Simpson proposed a second
equation (which is simply 1-D) which produces a value that increases as diversity
increases. The second equation (1-D) represents the probability that two randomly
()
∑∑×=
S
SS
IV
FVIV FVI

4-9
selected individuals will belong to different species. It is the second equation that
follows and was used to quantify herbaceous species diversity in the EMFS.

Simpson’s index of diversity ranges from 0.0 (low diversity) to almost 1.0 (high diversity)
and is expressed as a percent of probability.

where
SD = species diversity
TFA, TFB, TFn = total frequency for each species identified
TF = total frequency for all species.

4.5.3 Comparison to Previous Studies. In addition to describing plant communities
present at the time the chemical analytical samples were collected, plant community
characteristics were compared to conditions observed during previous sampling rounds
to gain an understanding of community dynamics and to identify inferences those
dynamics may have on interpretation of the analytical data.

Herbaceous data for cover and frequency were compared among the EMBS and the
1999 and 2002 EMFSs to identify trends. Density data collected in 2002 and 2005 were
not used for this comparison, because density data were not collected during the EMBS
or the 1999 EMBS. Data from the 1998 EMFS were excluded from the comparison as
not comparable, because that sampling round was performed in October while all other
sampling rounds were in the May time frame. The first killing frost occurs in late
August or early September. Therefore, the 1998 EMFS occurred more than a month
after the end of the growing season and composition of the plant communities can be
expected to be considerably changed over what is seen in the height of the growing
season of late May and early June.
⎥⎥
⎦
⎤
⎢⎢
⎣
⎡⎟⎠
⎞⎜⎝
⎛++⎟⎠
⎞⎜⎝
⎛+⎟⎠
⎞⎜⎝
⎛−=
222
......1 TF
TF
TF
TF
TF
TFSD nBA

4-10
A second comparison was made between vegetation data from the 2005 EMFS and the
2002 EMFS as a way of providing a more detailed description of the plant community
present in 2005 and the recent changes that have occurred. This comparison included
both shrub and herbaceous data for cover, frequency, and density.

4-11
Table 4.4-1. Analytical Parameters for Soil, Vegetation, Surface Water, and Sediment

PCDDs
Tetrachlorodibenzo-p-dioxin (TCDD)a
Pentachlorodibenzo-p-dioxin (PeCDD)a
Hexachlorodibenzo-p-dioxin (HxCDD)a
Heptachlorodibenzo-p-dioxin (HpCDD) a
Octachlorodibenzo-p-dioxin (OCDD)

PCDFs
2,3,7,8-Tetrachlorodibenzofuran (TCDF)a
Pentachlorodibenzofuran (PCDF)a
Hexachlorodibenzofuran (HxCDF)a
Heptachlorodibenzofuran (HpCDF)a
Octchlorodibenzofuran (OCDF)

VOCsb
QAPjP list (Tables 8-2 and 8-5) and library searchc

SVOCs
QAPjP list (Tables 8-2 and 8-5) and library searchc

PCBs
PCB-1016
PCB-1221
PCB-1232
PCB-1242
PCB-1248
PCB-1254
PCB-1260

Explosives
Nitroglycerine
2,4-dinitrotoluene
2,6-dinitrotoluene
2,4,6-trinitrotoluene
RDX
HMX
Tetryl
Metals
Aluminum
Antimony
Arsenic
Barium
Beryllium
Boron
Cadmium
Calcium
Chromium
Cobalt
Copper
Iron
Lead
Magnesium
Manganese
Mercury
Molybdenum
Nickel
Potassium
Selenium
Silver
Sodium
Thallium
Tin
Vanadium
Zinc

Notes:
a Total, plus the individual congeners listed in the QAPjP (tables 8-3, 8-4, and 8-6).
b Not analyzed in vegetation samples or in rinsates associated with vegetation samples.
c Tables 8-2 and 8-5 of the QAPjP provides a complete list of 8260 VOCs and 8270 SVOCs.

HMX = high melting explosive
PCB = polychlorinated biphenyl
PCDD = polychlorinated dibenzodioxin
PCDF = polychlorinated dibenzofuran
QAPjP = Quality Assurance Project Plan
RDX = cyclonite
SVOC = semivolatile organic compound
VOC = volatile organic compound

4-12
Table 4.5.2.1-1. Ranking Scale for Forage Value

Scale Status Description
1 Good Palatable species that are good producers with good nutrient content
2 Fair Species that may be slightly palatable, have fair nutrient content, produce
poorly, or become less desirable with maturity
3 Poor Species that are not palatable, offer little nutrition, or flavor milk and meat;
includes species for which no information was found
4 Poisonous Species that are known to cause illness, loss of fetuses, or death, if consumed

4-13
Figure 4.1-1. Sample Location Map

4-14
Figure 4.1-2. Rainbow Reservoir Sample Location

5-1
SECTION 5
STUDY COMPARABILITY ASSESSMENT

The primary purpose of the EMFS is the ongoing comparison of analytical results to the
benchmark data collected in the May 1996 EMBS. Maintaining data consistency for the
comparison of data from one event to another is critical. Comparability is ensured
through the use of standard sampling and analytical methods, specified target analyte
lists, and a consistent reporting format for nomenclature and measurement units. To
optimize comparability, the analytical methods and protocols employed during the
EMBS were, with a few exceptions, also specified for the 2005 EMFS. At the
conclusion of the 2002 EMFS study, reviewers determined that some chemicals of
potential concern (COPCs) and sampling media were providing little value to the study.
Consequently, analysis of anions and nutrients were not included in the 2005 EMFS.
VOC analyses were also discontinued on existing sampling locations and only
performed at locations new to the 2005 EMFS. Collection of subsurface soil samples
was also discontinued for the 2005 EMFS. Additional sampling locations and media
collected in support of the EMFS that were not sampled as part of the EMBS are treated
as new information and evaluated separately from the data collected from sample sites
established by the EMBS.

Many of the organic and inorganic analytes are naturally occurring in the environment.
For example, metals in soil are derived from natural geologic materials. Organic matter
in soil is derived from natural vegetation. Anthropogenic activities such as farming,
burning, and motor vehicle operation also contribute organic and inorganic chemicals to
the environment. The EMBS attempted to measure the random variability of naturally
occurring levels of components in the sampled media throughout the area of interest.

5.1 Chemical Analysis Data

Comparability, as it relates to the current study, is the degree to which data from the
EMFS can be meaningfully compared to the EMBS and previous EMFSs.

5-2
Comparability is achieved through the use of standard techniques/methods for sample
collection and analysis. Consistent use of nomenclature and reporting units is also
important. Data comparability also depends on data quality. Data of unknown quality
cannot be compared with confidence because accuracy and precision are unknown. To
optimize comparability, the analytical methods and protocols employed during the
EMBS were, with a few exceptions (see paragraph 5.1.2.1), also employed for the
2005 EMFS.

Analytical methods stipulated for the 2005 EMFS are the same methods used by the
EMBS and previous EMFS studies. The analytical methods and procedures were taken
from USEPA SW-846, USEPA Methods for Chemical Analysis of Water and Wastes
(USEPA 600/4-79-20), Official Methods of Analysis of the Association of Official
Analytical Chemists (AOAC) International, and American Society for Testing and
Materials (ASTM) published methodology.

5.1.1 Laboratory Comparability. Data variability may have been introduced by the
use of different laboratories for the EMBS and EMFSs. EMBS samples were submitted
to Environmental Science and Engineering, Inc. (ESE), for analysis. Samples collected
during the three previous EMFS events were submitted to Ecology & Environment, Inc.
(E&E), while the 2005 EMFS samples were analyzed at ELAB of Tennessee (ELAB).
Standardized analytical methods do not always dictate an exact approach for analysis
and frequently present options that are acceptable as long as certain quality control
(QC) criteria are met. Therefore, different laboratories, even though they employ the
same standard methods, may have minor differences in how the methods are
implemented or in how instrumentation is maintained that are all within normal operating
practice, but nonetheless may impact results. In the same vein, even when the same
laboratory is used over and over again in a long-term study, there may be variability in
results as laboratory policies and personnel change over time.

During the course of environmental monitoring at TOCDF, initiated in May 1996, there
have been advances in analytical instrumentation and methodology that have resulted
in lower detection limits. One example is the use of liquid chromatography in

5-3
conjunction with mass spectrometry (LC/MS), a combination that provides increased
resolution of the vegetation matrix (that is, better separation of individual compounds)
and provides positive identification of the detected compounds.

Where advances in instrumentation and methodology have lead to a reduction in
method detection limits (MDLs), as has been the case for PCDDs, PCDFs, and
mercury, analytes may be detected in the EMFS that were not detected in the EMBS.
This does not mean that the “newly” detected analytes were not present in the EMBS, it
just means that with the newer instrumentation or methodology, analytes can be
detected at lower levels than were previously possible.

Variation in MDLs among sampling events can produce noticeable effects on data
evaluation. This was particularly true when comparing means using either the t-test or
U-test. In cases where there are a large number of nondetects and where the MDLs
are different, the results of the statistical test may suggest a change in the data average
when, in fact, there was only a change in MDLs. For this reason, the comparability of
EMBS data and EMFS data must be closely scrutinized.

For some inorganic parameters, chemical analyses were performed using different
methods and instrumentation. This issue is most apparent in the varying MDLs for
metals among different sampling rounds. All analytical instrumentation experience
small fluctuations over time; however, long-term drift due to increased or decreased
sensitivity is of particular concern. All laboratories are required to perform MDL studies
for each instrument at least once a year. All nondetects obtained on that instrument are
reported using the detection limits calculated from the most recent MDL study. During a
long-term monitoring effort, there will always be some inherent variability in MDLs from
one year to another. An examination of the MDLs used by E&E in the 1998, 1999,
and 2001 EMFSs and ELAB in the 2005 EMFS show this pattern. Many analytes had
MDL variations that were relatively minor, but several showed a two- or three-fold
increase or decrease between the sampling rounds. The differences between the
laboratory MDLs in the EMBS and the EMFSs are greater than the differences seen
when comparing MDLs among the EMFSs. Several tests show similar MDLs, but

5-4
some, such as explosives, show differences that are greater than an order of
magnitude.

In addition to MDLs, each laboratory sets a reporting limit (RL) for each analyte,
method, and matrix combination. The RL is the concentration above which a result can
be considered to have quantitative significance. RLs are modified for sample-specific
criteria including percent moisture, subsample size, and dilution. There were several
changes in RLs between the EMBS and the EMFSs. The RL for some analytes
increased (for example, explosives in vegetation), while others decreased (for example,
mercury in soil).

5.1.2 Analytical Limitations. The analysis of soil and vegetation samples for organic
compounds presents a challenge, because a large amount of organic matter in the
sample usually causes a high level of interference that can result in false positives or an
exaggerated detection limit (false negative).

5.1.2.1 Analysis of Dioxins/Furans in Soil. PCDDs/PCDFs are produced as a result of
incomplete combustion or chemical reactions involving organic matter and chlorine that
can be transported long distances on atmospheric currents and found at measurable
concentrations throughout the world. High levels can generally be linked to specific
sources, such as incinerators or manufacturing facilities. In dry, heavily forested areas
where wildfires frequently occur, elevated concentrations tend to accumulate. Volcanic
activity can also deposit significant amounts of these compounds. Scientists speculate
that organic pollutants move through the atmosphere from relatively warm areas and
then condense at colder latitudes or altitudes onto vegetation, soil, and water. The main
point of accumulation of PCDDs/PCDFs in the environment is in the soil, where the
molecules tightly bind to organic matter in the soil. The ubiquitous nature of
PCDDs/PCDFs makes it difficult to find “clean” areas in the environment, even in
laboratory blanks, due to the sensitivity of the analytical instrumentation. Even with the
best laboratory practices and attempts to be scrupulously clean with all glassware and
reagents, dioxin laboratories routinely report extremely low levels of target compounds

5-5
in their method blank and field samples. These low levels may or may not have been
actually present in the environmental samples.

The ubiquity of dioxins and furans and the sensitivity of the instrumentation are of
particular concern for analytical laboratories. For the EMBS, analyses for
PCDDs/PCDFs in soil matrices were conducted using USEPA SW-846 Method 8280,
which is a gas chromatography/mass spectrometry (GC/MS) method. The analysis of
soil matrices for dioxins and furans is now routinely performed using SW-846
Method 8290. This procedure uses gas chromatography/high resolution mass
spectrometry (GC/HRMS) methodology to reduce the amount of interference
encountered during analysis.

5.1.2.2 Identification of Organic Compounds in Vegetation. The chemical analysis of
plant tissues for organic compounds can be challenging due to variables such as plant
age and natural variability, timing of sampling relative to the growing season,
environmental stresses such as temperature and sunlight, and incidental pollution
unrelated to the study site. The chemical composition of the plant can cause complex
interferences with organic analytes. The chemical and biological complexity of
vegetation can cause interferences in an analysis because the sample preparation
steps often involve solvent extraction or chemical digestion that can mobilize
naturally-occurring chemical and biological constituents as well as the targeted
compounds. Biological degradation products naturally found in plants can be
chemically similar to other organic compounds, potentially giving false positive
detections. Laboratories have reported that PCDDs/PCDFs may be created during the
analysis of such highly organic material such as plant tissue. The U.S. Army
Environmental Center (USAEC) method for explosives analysis has been shown to
produce false positives in plant material. USEPA SW-846 analytical methods have
been optimized for soil and aqueous media and may yield sub-optimal results when
used on other media such as plant material.

The analysis of vegetation samples for organic compounds is an atypical (nonroutine)
analysis for most environmental laboratories. As a result, the methodology is not rigidly

5-6
standardized. In many cases, these analyses are conducted using detectors that
cannot discriminate between closely related compounds. Compound identification is
based on retention time and not on a “molecular fingerprint” as in mass spectrometry
methods. Positive identification is not always possible. The non-specificity of the
detector can lead to false positives and introduces uncertainty into the results. For
example, positive results for nitroglycerine in plant samples collected for the EMBSs
have been viewed with skepticism, due to the presence of glycerine in plant tissue. The
identification of Tetryl and PCB-1254 also is suspect.

5.2 Seasonal Variability

Variations in climatic conditions between sampling events can have a negative impact
on data comparability. This can be compensated for, to some extent, by sampling at
the same time of year as the baseline sampling, ensuring that plants and soil are in
about the same stage of their annual cycle. The EMBS sample collection was
conducted in May 1996, and accordingly, subsequent sampling should be conducted
during the month of May to correspond to the baseline study. This reduces, but does
not eliminate, the potential effect of seasonal variability, allows enough time between
sampling events for any potential deposition to occur, and standardizes the periodicity
of sampling events. May is generally the time of optimum plant growth in the area.
Evenly timed sampling events facilitate the identification of trends in sample
concentrations and help to increase comparability of identified floral species.

Differences in temperature, humidity, air currents, sunlight, and life cycle stage can
influence the rates of deposition and decomposition/degradation of particulate and
gaseous contaminants. Although PCDDs/PCDFs do not break down easily in the
environment, decomposition can be accelerated in hot, dry locations receiving long
hours of intense sunlight.

Another factor that affects data comparability is seasonal variations in the matrices.
Vegetation and surface water samples are especially prone to seasonal variation.
There can be changes in the amount and vigor of foliage, differences in the nutrients

5-7
stored inside the plant, and differences in plant appearance (for example, plant maturity
that may affect proper identification). For example, the significant differences observed
in vegetation results between the EMBS and the 1998 EMFS were attributed to the fact
that the EMBS took place during May, whereas the 1998 EMFS was completed in
October.

There were several changes noted in the composition of vegetation during the interval
between the EMBS and each subsequent sampling event. These changes are the
result of invasion by other plant species, fire, cattle grazing, and human activities such
as off-road vehicle use and recreational uses of the land. Some human activity resulted
in a change in the type of environment present at the sample location, that is, a
sagebrush prairie becoming a saline meadow. None of the observed changes
appeared to be associated with activities at TOCDF.

Surface water samples from Rainbow Reservoir are subject to seasonal variability in the
water coming into the reservoir and seasonable variability in the flora and fauna of the
reservoir.

5.3 Data Evaluation Criteria

As noted in the Data Validation Report for the EMBS (Dames & Moore, 1997a),
laboratories may use internally generated acceptance criteria for ongoing QC purposes.
The data validation contractor for the EMBS evaluated data quality using the principles
and limits of the EPA Contract Laboratory Program National Functional Guidelines for
Organic and Inorganic Data Review (1994a). Analytical data collected for the
2005 EMFS were validated as described in the 2004 Final TOCDF QAPjP using the
National Functional Guidelines in order to maximize comparability of the data with the
results of the EMBS. In other words, the same type of observation by the validator
should result in the same type of data qualification and/or limitation on the use of the
data.

5-8
Data gathered in the EMBS and EMFSs underwent statistical evaluation. For the
baseline study, this included population distribution testing, calculation of the mean and
standard deviation of each detected analyte, calculation of the 99 percent UTL, and the
designation of comparison criteria. The 1998, 1999, and 2002 EMFSs included
evaluation of the means relative to the EMBS comparison criteria. However, the
concentration of contaminants observed at specific sampling locations during the EMBS
was not compared to the concentrations detected at the same location during the
1998 and 1999 EMFSs. It is possible that such a comparison may provide useful
information to determine whether a particular location or area within the overall study
area has experienced an increase in contaminant concentrations.

A method of evaluating analytical data for individual sites for evidence of change was
added for the 2002 EMFS and continued with the 2005 EMFS. The concentrations of
potential contaminants were examined for trends over time at each location. Evaluating
the data in this manner will facilitate early detection of potential contaminant deposition
at sample locations, possibly before the established comparison criteria are exceeded.

6-1
SECTION 6
CHARACTERIZATION RESULTS – PLANT COMMUNITIES AND SOIL

Site characteristics including topography, soil type, and vegetation characteristics were
recorded at each of the 42 soil and vegetation sampling sites. This section describes
results of site physical characterization, soil typing, and plant community analysis. The
terms “sample location” and “sample site” are used interchangeably while the term
“sample plot” refers to a sub-section of the sample site. For example, data from
10 herbaceous plots were collected at each sample site.

6.1 Physical Characterization of Sample Locations

Physical characteristics observed at each sample location were recorded on field forms
by the sampling team. Field data collection forms for recording physical measurements
and observations were based on the Standing Operating Procedures (SOPs) included
in the project FSP. Copies of the completed field forms are provided in appendix C.

The following characteristics are summarized for each sample location in table 6.1-1:

a. Elevation – reported in feet

b. Percent Slope – calculated based on contouring of elevation data
collected at center point, three surface soil sampling locations, and four
perimeter readings at points north, south, east, and west of the center
point

c. Aspect – general direction or azimuth of down slope based on contoured
elevation data—reported in degrees

d. Aspect Transformation – computed as one plus the cosine of the aspect
minus 45 degrees

6-2
e. Plant Community – Description relative to surrounding area (for example,
sagebrush [Artemisia tridentata] area surrounded by prairie). Other
information such as disturbances or man-made features were also
recorded.

A summary of the following additional physical variables recorded for each soil sample
location is provided in table 6.1-2.

• GPS Location. The GPS location refers to the place where the three
samples were collected to form the composite sample for a given sample
site. Locations are given in Universal Transverse Mercator (UTM)
coordinates as well as latitude and longitude coordinates.

• Sector and Location. As described in the FSP, each sampling site was
divided into sectors. The sector name is given (for example 8A) as well as
the location within the sector identified as a distance in feet and inches
and an azimuth (for example 33 feet 6 inches at 319 degrees). Location
was measured from the center of the sampling site.

• Soil Description. This variable is a general description of soil type, color,
organic matter, and other appropriate descriptors.

6.2 Characterization of Vegetation Composition and Structure

Data were collected describing the plant communities found at the sampling sites. This
report describes the plant communities encountered and identifies changes in the
makeup of the plant communities over the course of the study.

Shrub and herbaceous layers are described separately in this report. The following
definitions from Parker 1979 were used throughout this report.

6-3
a. Grass – grasses have round or slightly flattened stems with visible joints
(nodes), hollow or pithy centers; leaves with parallel veins on two sides of
the stem

b. Herb – A non-grass-like herbaceous plant with broad leaves with net-like
veins. Herbs (also called forbs) may be annuals, biennials, or perennials
but always lack significant thickening by secondary woody growth and
have perenniating buds borne at or below the ground surface.

(1) Annual – Annual plants live only one season and do not come up a
second year from roots or crowns.

(2) Biennial – Biennial plants live just 2 years.

(3) Perennial – Perennial plants live more than 2 years, producing
leaves and stems from the same crown each subsequent year.

c. Graminoid – Grasses or grass-like plants. Grass-like plants are similar to
grass but without readily visible joints; have solid stems (not hollow); veins
in the leaves are parallel. Sedges, with triangular stems (in cross-section),
and rushes with round or oval stems (in cross section) are considered
graminoid.

d. Shrub – A woody plant, normally perennial, branching from the base with
several stems. A shrub is usually less than 13 to 16 feet in height.

e. Low Shrub – A low growing shrub usually under 1.5 feet tall, never
exceeding 3 feet tall at maturity.

f. Tree – A perennial, woody plant with a single stem (trunk), normally
greater than 4 to 5 meters (13 to 16 feet) tall at maturity.

6-4
Table 6.2-1 lists plant species recorded during the 1996 baseline sampling and four
subsequent studies conducted in 1998, 1999, 2002, and 2005. For each species, the
life form (shrub, tree, etc.), nativity (native or alien to the area), decreaser/increaser
index, forage value, and year of observation (including notes on erroneous or
incomplete identifications from 1996 through 2005) are provided. All sample locations
were found to be low quality rangeland dominated by increaser and invader species.

Table 6.2-2 summarizes composition and structure of the shrub community at each
sample location. Figures 6.2-1 and 6.2-2 provide interpretations of the spatial
distribution of the shrub species and percent shrub coverage in the study area.

Table 6.2-3 summarizes the herbaceous species, vegetation composition, and structure
of each sample location. Figures 6.2-3 and 6.2-4 illustrate interpretations of the spatial
distribution of the dominant herbaceous species and percent herbaceous coverage in
the study area.

6.2.1 Shrub Layer Characterization. Results of the 2005 EMFS are generally similar
to those of the baseline and prior follow-on studies. Specific findings for shrub species
are noted as follows:

a. Big sagebrush (Artemisia tridentata) was the dominant species observed
at 30 of the 42 (71 percent) sample locations. Big sagebrush was
observed at all sample locations (either dominant or co-dominant) with the
exception of six sites (0214, 0623, 0802, 0819, 1022, and 1416), All of
these sites, except 1022, are new sample locations in the 2005 EMFS.

b. Utah Juniper (Juniperus osteosperma) dominated or was a co-dominant at
four sample locations (1022, 1222, 1223, and 1416).

c. Mormon tea (Ephedra spp.) was recorded for the first time in 2005.
Mormon tea was identified at sample locations 0623, 0812, 1011, and
1209. Two of the sites (0623 and 1209) were investigated for the first time

6-5
in 2005. At sites 0812 and 1011, only a few small specimens were
identified indicating that they are newly established.

d. Greasewood (Sarcobatus virmiculatus) was the dominant species at four
sample locations (0111, 0214, 0420, and 0819). Forage values at these
sample locations rate a 4 (poisonous) because young shoots and leaves
of greasewood can be poisonous to cattle and sheep (MacMahon, 1990).

e. Shadscale (Atriplex canascens) was the dominant or co-dominant shrub at
ten sites. Its presence is consistent with past studies with populations
expected to be constant or increasing because shadscale persists or
increases when other plants are disappearing due to human impacts such
as cattle grazing (MacMahon, 1990).

f. Pinyon pine (Pinus edulis) was identified for the first time at two sample
locations (1022 and 1416). The pinyon pine trees are well established at
these sites and are not considered new growth since 2002. It is assumed
that the trees were not observed in past samplings because of the number
and density of Utah juniper at these locations.

g. The average shrub forage value for all 42 sample locations is 2.77,
indicating that the area-wide forage value is fair to poor. Only three
sample locations (0802, 1108, and 1305) had a “good” forage
classification (value of one) because of the presence of shadscale.

h. Broom snakeweed (Gutierezia sarothrae) and winterfat (Ceratoides
lanata) were identified during 2005 and previous investigations. However,
past investigations identified them as herbaceous plants where the
2005 investigation classified them as shrubs.

6-6
i. The average shrub coverage per hectare is 5,040 square meters per
hectare (m2/ha) (approximately 50 percent cover), with an average height
classification of 1.81 (0.5 to 1 meter).

j. The number of clumps per hectare averaged 5,825 with an average vigor
value of 0.60.

6.2.2 Herbaceous Layer Characterization. Significant changes in the herbaceous
layer were observed in the 2005 EMFS. In particular, the dominance of weedy annuals
such as burr buttercup (Rancunculus reconditus) and cheatgrass (Bromus tectorum) are
indicative of sites that have been stressed. The presence of flixweed (Descurainia
sophia) and tansy mustard (Descurainia pinnata) further indicate stress
(MacMahon, 1990).

The increase of cheatgrass as a dominant species is noteworthy because cheatgrass
plays a role in determining the amount of sagebrush on a site. Additionally, cheatgrass
successfully competes with many native grasses. It also produces large quantities of
stems and leaves that burn readily when dry and tends to increase the frequency and
intensity of fire (MacMahon, 1990). This situation does not favor big sagebrush
(Artemisia tridentate). A summary of the findings are presented as follows:

a. Burr buttercup (Rancunculus reconditus) is the most commonly
encountered herbaceous species, dominating 25 sample locations
(59 percent) and occurring in a total of 40 sample locations (95 percent).

b. Cheatgrass (Bromus tectorum) was the second most commonly
encountered herbaceous species, dominating 12 sample locations
(29 percent) and occurring in a total of 27 sample locations (64 percent).

c. Flixweed (Descurainia sophia), is a dominant or co-dominant species at
8 sites (19 percent). The presence of this invader species continues to
support the conclusion that Rush Valley is being influenced by stresses

6-7
such as drought, cattle grazing, and fire. Flixweed was not identified as a
dominant or co-dominant species at any of the sample locations during
previous studies.

d. The area-wide decreaser/increaser index calculated for 2005 further
indicates that disturbance has occurred (average decreaser/increaser
index area-wide is 2.8). The herbaceous layer at 38 of the 42 sample
locations (90 percent) was dominated by invader species, 3 locations
(7 percent) are dominated by increaser species, and 1 location (0707 or
2 percent) had species that could not be identified (based on previous
samplings, the dominant unidentified species is assumed to be desert
saltgrass).

e. Foraging conditions across all the 2005 locations are fair to poor (average
herbaceous forage value is 2.5). The herbaceous layer is dominated by
fair forage species at 17 sample locations (40 percent) and by poor forage
species at 24 sample locations (57 percent). Good forage species
dominated none of the sample locations. One sample location (2 percent)
did not have a forage value because the species at the location (0707)
could not be identified.

f. The area-wide herbaceous ground cover averaged 49 percent for all
sample location sectors as calculated from the field data forms.

6.3 Vegetation Summary and Comparison to Previous Studies

A summary of the combined 2005 EMFS vegetation characteristics is provided in
table 6.3-1. Notable trends associated with the historical shrub data are presented in
the histograms provided in figures 6.3-1 through 6.3-3. Total vegetation coverage and
the relative dominance of the total shrub and herbaceous populations observed in the
study are shown in figure 6.3-4.

6-8
6.3.1 Shrub Data Comparison to Previous Studies. Cover, clumps per hectare,
average height class, and average vigor for shrubs are presented. Sixteen new sites
(15 programmed new sites and one replacement site) were sampled in 2005 so there is
no comparison of these data to previous studies. Two sample locations (0112 and
0224) were not sampled in 2005, so findings for these two sites are not included.

Shrub layer characteristics were reviewed to evaluate changes in composition and
structure by comparing the 1996 EMBS through 2005 EMFS data. A summary of the
findings is as follows:

a. Average site-wide areal coverage for shrubs increased to 5,040 m2/ha in
2005 versus 2,548 m2/ha in 1996. Of the 23 locations sampled in 1996
and 2005, only two locations in 2005 (locations 0616 and 0914) had a
decrease in areal coverage versus 1996. Average areal coverage also
increased in 2005 (5,040 m2/ha) versus 2002 (3,001 m2/ha). Areal
coverage was greater at all sample locations in 2005 versus 2002, with
the exception of location 1009.

b. Shrub clumps per hectare continue to be high versus the 1996 baseline
and 1998/1999 EMFSs. In 2005, area-wide shrub clumps per hectare
averaged 5,825 versus 1,502 in 1996 (figure 6.3-1). Every 2005 sample
location had a greater number of clumps per hectare versus 1996, 1998,
and 1999. Clumps per hectare decreased slightly in 2005 (5,825) versus
2002 (5,986). However, the clumps per hectare observed in 2005 and
2002 are comparable.

c. Another change observed during the 2005 EMFS was that an all time high
number of individual shrub clumps was observed at seventeen of the
26 sample locations (27 percent).

d. At sample location 0707, shrubs were observed but all were dead in the
1996 EMBS and each EMFS. The absence of shrubs is due to the

6-9
presence of saline or alkaline soils that do no promote the growth of
shrubs. The saline/alkaline soil has resulted from a berm constructed
nearby that changed water flow.

e. The substantial increase of new/young growth shrubs at the majority of the
sites has resulted in a large portion of the species population to be
classified within the low end of the height class (average height class in
2005 was 1.81 versus 2.48 in 1996). Figure 6.3-1 shows the significant
increase in the number of shrub clumps observed. Figure 6.3-2 shows the
corresponding decrease in average height classification. This is likely a
result of the large number of new/young growth shrub clumps observed.
As shown in figure 6.3-3, mean shrub cover decreased by 20 percent from
1996 to 1998. The trend in shrub coverage has since increased from
1998 through 2005.

f. Average area-wide vigor decreased in 2005 versus 2002 and each of the
previous studies. This could be a result of different interpretation by the
botanists but may also be a result of increased competition between
shrubs (areal coverage of shrubs and clumps of shrubs per hectare have
increased) and the continued increase in invasive herbaceous species
that compete with the shrubs. It may also reflect cumulative effects on
shrub health caused by the drought experienced from 1999 through 2004.

6.3.2 Herbaceous Data Comparisons. The EMBS FSP required that only cover and
frequency data be collected for herbaceous species. Consequently, density data
(numbers of individual plants) were not collected in the EMBS or 1999 EMFS.
Therefore, comparisons of 2005 EMFS data to the EMBS or 1999 EMFS will only
involve cover and frequency. The 2002 EMFS was the first time that data on numbers
of individuals per species was recorded. Therefore, comparison of 2005 EMFS
herbaceous data to the 2002 EMFS data includes this additional parameter.

6-10
6.3.2.1 Comparison of 2005 EMFS to EMBS. The EMBS specified comparison of
herbaceous species based on cover and frequency. Density data were not reported in
the EMBS. Table 6.3.2.1-1 shows cover values for the 10 species with the greatest
percent cover during the EMBS and the EMFSs of 1999, 2002, and 2005. In addition to
species names and percent cover, the table includes the importance value and forage
value for each species. The total cover of all species and the number of species
recorded in a given year are shown at the bottom of the table. The percent cover and
importance values represent means for the listed species across all sampling sites in a
given year. 1998 EMFS data is not included because that sampling round was not
performed in the May time frame, and in that respect, is not comparable.

Total cover decreased markedly from 1996 to 2002 and recovered by just over half in
the 2005 EMFS. The dramatic decrease in cover from 1996 to 2002 is an indication of
a high level of stress on the herbaceous community. By 2005 the level of stress was
less, allowing some recovery of the plant community.

Importance values given in the table are the sum of relative cover and relative
frequency for each species divided by the sum of relative cover and relative frequency
for all species. This statistic is a measure of a species importance in the community.
Relative density, which is usually a part of the importance value calculation, was not
included because density data were not collected in the EMBS or 1999 EMFS. The
rank order for importance does not necessarily follow the order when cover alone is
measured (compare the importance values for species POCU and LEPE in
table 6.3.2.1-1). A species with a high cover value but low frequency may have lesser
importance than a species with less cover but much greater frequency.

Examination of the forage values reveals that from 1996 to 2002 the dominant species
changed from species with good or fair forage value to species with fair or poor forage
value. Although species count and average cover increased by the time of the
2005 EMFS, the dominate species remain those with fair or poor forage value. Either
the environmental stress that led to the decline of the good forage value species has

6-11
continued or it takes longer than a single season for those species to regain dominance
once the stress has lessened.

The main stresses observed during the course of the TOCDF EMFS include cattle
grazing, fire, and drought. Evidence of cattle grazing, reported in field notes as signs of
fresh droppings and hoof prints, has been inconsistent between years and sites.
Likewise, the influence of fire has been spotty. Even though it may be assumed that all
of the sampling sites have received deposition of smoke and particulate matter
emanating from the numerous fires, only a few of the sampling sites have actually been
burned during the time of the monitoring study. By comparison, changes in precipitation
can be expected to be experienced relatively evenly over the study area, which is on
relatively level terrain and only a few kilometers long and wide.

The changes observed in the herbaceous vegetation coincide very well with changes in
precipitation reported from 1996 to 2005 (see paragraph 3.2). Above average
precipitation was received in 1995, 1996, 1997, and 1998. Starting in 1999, Tooele,
Utah, experienced a drought that lasted through 2004 with 2002, which exhibited
extreme drought conditions, being the driest. The drought abated in 2005. In fact,
May 2005, with 7.51 inches of precipitation, was the wettest May on record and the
second wettest month overall in 79 years of U.S. Weather Service data for Tooele.

From the perspective of the herbaceous community, 1996 and 2002 can be looked
upon as “stable” years and 1999 and 2005 can be looked upon as “transition” years.
1996 was the fourth year in a string of years with above normal precipitation. The year
2002 was the fourth year in a string of years with below normal precipitation. The year
1999 was the first year of the drought that lasted from 1999 through 2004, and 2005 is
the year that the drought ended.

Precipitation appears to be the most important factor in determining health of the
herbaceous community. This has implications for interpretation of chemical analytical
data as well. Plants under greater stress from lack of moisture may accumulate
materials from the environment at different rates than plants under less stress.

6-12
Likewise, soil biota are more active when more moisture is available. It can also be
expected that material transport within the soil will vary with differences in moisture
percolation and evaporation. These factors combined mean that differences in COPC
concentrations in soil or vegetation from one sampling round to another may be more
likely due to climatic trends than to emissions from a particular source such as the
TOCDF common stack.

6.3.2.2 Herbaceous Comparison 2005 to 2002. Herbaceous layer characteristics data
were reviewed to evaluate changes in composition and structure by comparing the
2005 EMFS data to the 2002 EMFS. A summary of the findings is presented as follows:

a. The area-wide average decreaser/increaser index for all sample locations
slightly increased from 2002 (2.68) to 2005 (2.76), indicating that the
herbaceous community is continuing to trend away from native species.
This continuing trend is most likely in response to drought, cattle grazing,
and fire. The increase in the decreaser/increaser index is supported
through the observation of more invader species (bur buttercup,
cheatgrass, etc.) during the herbaceous characterization.

b. Forage value is determined on the basis of palatability, nutrient content,
and dependability as a forage supply for grazing animals (Parker, 1979).
Forage value is a relative factor that varies depending on the kind of
livestock using the plants, the soil conditions, and the season. A forage
value of one is good, where as a value of three is poor. The area-wide
average forage value increased slightly from 2.36 in 2002 to 2.50 in 2005,
indicating a decrease in forage quality.

c. Species richness increased from 0.37 in 2002 to 0.80 in 2005. On
average, three herbaceous species were identified at sample locations in
2002 versus eight identified in 2005. In 1996, an average of seven
species was identified at area-wide sampling locations. The low number

6-13
of species identified in 2002 is a result of extreme drought conditions that
plagued Rush Valley in 2002.

d. Average area-wide percent ground cover increased from 29 percent in
2002 to 49 percent in 2005. The significant increase in percent cover is
directly related to a significant increase in precipitation between the two
sampling periods. In 2002, a total of 13.6 inches of annual precipitation
was documented, which is significantly below average annual levels and is
considered a drought condition for Rush Valley. In comparison,
18.75 inches of precipitation was recorded by 22 July 2005.

e. It is reasonable to conclude that the decrease in numbers of species and
the decrease in percent cover observed in 2002 is a result of the drought
conditions.

6-14
Table 6.1-1. Sample Location Physical Variables

Sample
Location
Elevation
(feet) Percent Slope
Aspect
(degrees)
Aspect
Transformationa
Plant
Communityb
0111 5087.1 1.76 72 1.891 3
0112 5050.0 2 285 0.500 3
0214 5028.5 0.12 45 2.000 2
0224 5060.0 7 115 1.340 3
0308 5080.5 0.83 74 1.875 2
0400 5311.1 2.9 89 1.719 3
0416 5011.5 2.52 267 0.257 3
0420 5010.2 19.04 128 1.122 2
0515 5035.1 6.59 188 0.201 3
0611 5031.2 0.19 315 1.000 2
0613 5069.8 4.59 207 0.049 3
0616 5031.0 1.07 322 1.122 3
0618 5022.0 1.71 258 0.161 3
0623 4984.3 5.31 290 0.577 N/A
0707 5035.3 0.19 135 1.000 1
0714 5162.2 2.12 180 0.293 2
0802 5115.1 1.23 315 1.000 1,2
0812 5129.2 3.84 148 0.775 3
0813 5185.6 1.87 172 0.398 3
0817 5110.1 3.15 342 1.454 3
0819 5060.1 3.87 284 0.485 N/A
0914 5229.4 1.19 297 0.691 3
1004 5035.8 1.4 164 0.515 2
1007 5059.2 0.56 225 0.000 2
1009 5135.9 1.73 184 0.245 3
1011 5179.7 2.39 270 0.293 2
1013 5256.0 5.21 255 0.134 3
1015 5285.5 1.77 283 0.470 3
1018 5191.9 2.38 336 1.358 3
1022 5366.0 5.65 295 0.658 4

6-15
Table 6.1-1. Sample Location Physical Variables (Continued)

Sample
Location
Elevation
(feet) Percent Slope
Aspect
(degrees)
Aspect
Transformationa
Plant
Communityb
1108 5138.8 0.68 169 0.441 3
1202 5049.8 1.01 88 1.731 3
1209 5154.5 1.06 180 0.293 3
1214 5444.1 2.55 242 0.044 3
1218 5322.5 3.76 267 0.257 3
1222 5613.6 4.22 233 0.010 4
1223 5605.1 9.11 175 0.357 3,4
1305 5074.5 5.33 264 0.223 2
1412 5431.1 3.95 220 0.004 3
1416 5818.6 12.45 262 0.201 4
1508 5243.1 3.05 236 0.018 3
1706 5182.6 2.25 225 0.000 1
1710 5664.7 6.98 231 0.005 3
1808 5493.5 6.66 283 0.470 3

Notes:
a Aspect Transformation = 1+Cosine(Aspect-45º)
b Plant Community
1 = Sample locations with no shrub layer or with sagebrush only in the shrub plot
2 = Sample locations in isolated sagebrush communities
3 = Sample locations in sagebrush prairies
4 = Sample locations in woodlands

N/A = not applicable

6-16
Table 6.1-2. Soil Samples Collected for the 2005 EMFS

Grid
ID
Sample
ID GPS/Name GPS Location Sector/Location Soil Description
0111 0111S5 0111A EUTM-377604.457 NUTM-
4464380.888
Longitude- (-)112.440623105
Latitude-40.320991329
1B/ 35',7" - 30º Sandy Silt, light brown, dry with small roots
0111B EUTM-377611.866 NUTM-
4464384.192
Longitude- (-)112.440536560
Latitude-40.321022174
1B/ 60',2" - 41º Sandy Silt, light brown, dry with small roots
0111C EUTM-377615.508 NUTM-
4464389.339
Longitude- (-)112.440494689
Latitude-40.321069058
1B/ 82',8" - 36º Sandy Silt, light brown, dry with small roots
0112 0112S2 Did not sample for the 2005 Follow-on Study
0214 0214S5 0214A EUTM-379628.808 NUTM-
4466272.679
Longitude- (-)112.417159403
Latitude-40.338324038
1B/ 23',3" - 43º Sandy, silt, fine, dry light brown trace of root hairs
0214B EUTM-379633.864 NUTM-
4466280.757
Longitude- (-)112.417101419
Latitude-40.338397522
1B/ 52',4" - 32º Sandy, silt, fine, dry light brown trace of root hairs
0214C EUTM-379638.324 NUTM-
4466284.595
Longitude- (-)112.417049643
Latitude-40.338432734
1B/ 72' - 35º Sandy, silt, fine, dry light brown trace of root hairs

6-17
Table 6.1-2. Soil Samples Collected for the 2005 EMFS (Continued)

Grid
ID
Sample
ID GPS/Name GPS Location Sector/Location Soil Description
0224 0224S2 Did not sample for the 2005 Follow-on Study
0308 0308S5 0308A EUTM-379181.854 NUTM-
4460246.410
Longitude- (-)112.421281489
Latitude-40.283983638
1B/ 32',10" - 30º Sandy, silt, light gray, dry with roots
0308B EUTM-379188.914 NUTM-
4460251.095
Longitude- (-)112.421199342
Latitude-40.284026853
1B/ 58',10" - 37º Sandy, silt, light gray, dry with roots
0308C EUTM-379193.829 NUTM-
4460254.553
Longitude- (-)112.421142189
Latitude-40.284058715
1B/ 79' - 36º Sandy, silt, light gray, dry with roots
0400 0400S5 0400A EUTM-377677.179 NUTM-
4452641.176
Longitude-(-)112.437526742
Latitude-40.215267819
1A/ 33', 8" - 5º Silt, sand (5%), with pebbles (5%), loose, medium brown to
light yellow brown
0400B EUTM-377682.978 NUTM-
4452649.525
Longitude-(-)112.437460203
Latitude-40.215343862
1A/ 66', 11" - 13º Silt, no sand, with pebbles (3%), medium brown to light
yellow brown
0400C EUTM-377683.377 NUTM-
4452657.891
Longitude-(-)112.437457110
Latitude-40.215419272
1A/ 92', - 8.5º Silt, sand (5%), trace of pebbles, medium brown to light
yellow brown
0416 0416S5 0416A EUTM-379325.138 NUTM-
4468827.8999
Longitude-(-)112.421216640
Latitude-40.361293726
5B/ 26', 5" - 210º Sandy, silt, buff, and moist

6-18
Table 6.1-2. Soil Samples Collected for the 2005 EMFS (Continued)

Grid
ID
Sample
ID GPS/Name GPS Location Sector/Location Soil Description
0416B EUTM-379319.897 NUTM-
4468821.571
Longitude-(-)112.421277153
Latitude-40.361235969
5B/ 51',6" - 207º Sandy, silt, buff, and moist
0416C EUTM-379310.708 NUTM-
4468811.843
Longitude-(-)112.421383504
Latitude-40.361147028
5B/ 92',9" -
207.5º
Sandy, silt, buff, and moist
0420 0420S5 0420A EUTM-378926.717 NUTM-
4472514.618
Longitude-(-)112.426607872
Latitude-40.394440097
1B/ 14',3" - 35º Gravelly, silty sand with F-M gravel and cobbles sub
angular, light brown and dry
0420B EUTM-378931.002 NUTM-
4472521.330
Longitude-(-)112.426558674
Latitude-40.394501176
1B/ 39',2" - 27º Gravelly, silty sand with F-M gravel and cobbles sub
angular, light brown and dry
0420C EUTM-378941.445 NUTM-
4472526.915
Longitude-(-)112.426436716
Latitude-40.394552986
1B/ 76',3" - 37.5º Gravelly, silty sand with F-M gravel and cobbles sub
angular, light brown and dry
0515 0515S5 0515A EUTM-380222.109 NUTM-
4467781.388
Longitude-(-)112.410459388
Latitude-40.351997627
8A/ 39' - 33º Gravelly, silty sand, light brown and dry
0515B EUTM-380218.524 NUTM-
4467786.083
Longitude-(-)112.410502471
Latitude-40.352039401
8A/ 59' - 37º Gravelly, silty sand, light brown and dry

6-19
Table 6.1-2. Soil Samples Collected for the 2005 EMFS (Continued)

Grid
ID
Sample
ID GPS/Name GPS Location Sector/Location Soil Description
0515C EUTM-380215.462 NUTM-
4467794.627
Longitude-(-)112.410540129
Latitude-40.352115911
8A/ 88' - 35º Gravelly, silty sand, light brown and dry
0611 0611S5 0611A EUTM-381443.843 NUTM-
4463214.035
Longitude-(-)112.395229197
Latitude-40.311035804
1B/ 22',4" - 26º Silt, no sand or pebbles, medium brown
0611B EUTM-381447.214 NUTM-
4463216.545
Longitude-(-)112.395190003
Latitude-40.311058889
1B/ 36',10" - 30º Silt, no sand or pebbles, medium brown
0611C EUTM-381453.803 NUTM-
4463223.264
Longitude-(-)112.395113730
Latitude-40.311120338
1B/ 67',9" - 32º Silt, no sand or pebbles, medium brown
0613 0613S5 0613A EUTM-381159.192 NUTM-
4465660.800
Longitude-(-)112.399033096
Latitude-40.333032423
8A/ 32',1" - 324º Silt, trace of sand, pebbles sub angular (5%), medium
brown
0613B EUTM-381160.710 NUTM-
4465666.701
Longitude-(-)112.399016328
Latitude-40.333085778
8A/ 49',8" - 334º Silt, trace of sand, pebbles sub angular (5%), medium
brown
0613C EUTM-381151.999 NUTM-
4465673.812
Longitude-(-)112.399120174
Latitude-40.333148584
8A/ 80',2" - 322º Silt, trace of sand, pebbles and cobbles sub angular to sub
rounded (15%), medium brown

6-20
Table 6.1-2. Soil Samples Collected for the 2005 EMFS (Continued)

Grid
ID
Sample
ID GPS/Name GPS Location Sector/Location Soil Description
0616 0616S5 0616A EUTM-380852.884 NUTM-
4468553.277
Longitude-(-)112.403177870
Latitude-40.359040012
7A/ 27' - 275º Silty, sand with fine sub angular gravel, brown, moist with
abundant roots
0616B EUTM-380840.770 NUTM-
4468556.368
Longitude-(-)112.403321069
Latitude-40.359066118
7A/ 67' - 273º Silty, sand with fine sub angular gravel, brown, moist with
abundant roots
0616C EUTM-380837.521 NUTM-
4468559.138
Longitude-(-)112.403359838
Latitude-40.359090601
7A/ 80' - 280º Silty, sand with fine sub angular gravel, brown, moist with
abundant roots
0618 0618S5 0618A EUTM-381068.140 NUTM-
4470188.377
Longitude-(-)112.400948475
Latitude-40.373797313
3A/ 22',8" - 95.5º Sandy silt with trace of fine gravel buff, dry, about 20%
voids
0618B EUTM-381077.708 NUTM-
4470185.673
Longitude-(-)112.400835294
Latitude-40.373774329
3A/ 53',5" - 94º Sandy silt with trace of fine gravel buff, dry, about 20%
voids
0618C EUTM-381082.163 NUTM-
4470177.617
Longitude-(-)112.400781330
Latitude-40.373702405
3A/ 78',5" -
118.5º
Sandy silt with trace of fine gravel buff, dry, about 20%
voids
0623 0623S5 0623A EUTM-382526.972 NUTM-
4475068.415
Longitude-(-)112.384669296
Latitude-40.417956493
1B/ 30' - 38º Sandy silt, buff, dry

6-21
Table 6.1-2. Soil Samples Collected for the 2005 EMFS (Continued)

Grid
ID
Sample
ID GPS/Name GPS Location Sector/Location Soil Description
0623B EUTM-382534.530 NUTM-
4475074.513
Longitude-(-)112.384581361
Latitude-40.418012483
1B/ 60' - 36º Sandy silt, buff, dry
0623C EUTM-382542.488 NUTM-
4475079.371
Longitude-(-)112.384488474
Latitude-40.418057361
1B/ 90' - 35º Sandy silt, buff, dry
0707 0707S5 0707A EUTM-382036.791 NUTM-
4459644.876
Longitude-(-)112.387595196
Latitude-40.278973426
5B/ 23' - 220º Silt, high organic content, dark brown
0707B EUTM-382028.418 NUTM-
4459639.296
Longitude-(-)112.387692636
Latitude-40.278921989
5B/ 57',2" - 222º Silt, high organic content, dark brown
0707C EUTM-382024.593 NUTM-
4459629.745
Longitude-(-)112.387735853
Latitude-40.278835422
5B/ 86',2" - 212º Silt, high organic content, dark brown
0714 0714S5 0714A EUTM-382120.141 NUTM-
4466859.456
Longitude-(-)112.387944899
Latitude-40.343964523
8B/ 16',9" - 355º Silty sand (F) with sandy silt with fine sub angular gravel,
buff-brown moist
0714B EUTM-382117.144 NUTM-
4466873.113
Longitude-(-)112.387982690
Latitude-40.344087104
8B/ 61',3" - 342º Silty sand (F) with sandy silt with fine sub angular gravel,
buff-brown moist

6-22
Table 6.1-2. Soil Samples Collected for the 2005 EMFS (Continued)

Grid
ID
Sample
ID GPS/Name GPS Location Sector/Location Soil Description
0714C EUTM-382118.513 NUTM-
4466880.184
Longitude-(-)112.387967891
Latitude-40.344150975
8B/ 86' - 344º Silty sand (F) with sandy silt with fine sub angular gravel,
buff-brown moist
0802 0802S5 0802A EUTM-383651.742 NUTM-
4455299.609
Longitude-(-)112.367815266
Latitude-40.240062603
1B/ 20',5" - 29º Silt, no sand or pebbles, medium brown to gray
0802B EUTM-383656.925 NUTM-
4455303.701
Longitude-(-)112.367755095
Latitude-40.240100176
1B/ 41' - 36.5º Silt, no sand or pebbles, medium brown to gray
0802C EUTM-383668.477 NUTM-
4455310.258
Longitude-(-)112.367620514
Latitude-40.240160841
1B/ 83',9" - 41º Silt, no sand or pebbles, medium brown to gray
0812 0812S5 0812A EUTM-383030.190 NUTM-
4464780.443
Longitude-(-)112.376852000
Latitude-40.325367599
8A/ 22',8" - 325º Silt, sand (5%), pebbles sub rounded (20%), medium to
light brownish gray
0812B EUTM-383026.893 NUTM-
4464784.710
Longitude-(-)112.376891584
Latitude-40.325405570
8A/ 39' - 316º Silt, sand (5%), pebbles sub rounded (20%), medium to
light brownish gray
0812C EUTM-383025.521 NUTM-
4464794.001
Longitude-(-)112.376909431
Latitude-40.325489055
8A/ 69',2" - 326º Silt, sand (5%), pebbles sub rounded (20%), medium to
light brownish gray

6-23
Table 6.1-2. Soil Samples Collected for the 2005 EMFS (Continued)

Grid
ID
Sample
ID GPS/Name GPS Location Sector/Location Soil Description
0813 0813S5 0813A EUTM-383254.692 NUTM-
4465640.836 Longitude-(-
)112.374367318
Latitude-40.333148308
2B/ 50',4" - 72º Silt, sand (5%), pebbles sub angular (10%), medium brown
0813B EUTM-383256.989 NUTM-
4465644.451
Longitude-(-)112.374340940
Latitude-40.333181189
2B/ 57',9" - 84º Silt, sand (10%), pebbles and cobbles (15%), medium
brown with reddish tint
0813C EUTM-383264.416 NUTM-
4465643.342
Longitude-(-)112.374253333
Latitude-40.333172247
2B/ 81',9" - 77º Silt, trace of sand, pebbles (10%), medium brown
0817 0817S5 0817A EUTM-382041.114 NUTM-
4469444.266
Longitude-(-)112.389352953
Latitude-40.367233684
1B/ 26',1" - 26º Gravelly silty sand (F-C), ground is fine to move, sub
rounded to sub angular, soft, wet with abundant roots
< 1/16"
0817B EUTM-382048.030 NUTM-
4469446.641
Longitude-(-)112.389271954
Latitude-40.367256056
1B/ 44',10" - 37º Gravelly silty sand (F-C), ground is fine to move, sub
rounded to sub angular, soft, wet with abundant roots
< 1/16"
0817C EUTM-382053.232 NUTM-
4469457.540
Longitude-(-)112.389212713
Latitude-40.367354958
1B/ 82',11" - 27º Gravelly silty sand (F-C), ground is fine to move, sub
rounded to sub angular, soft, wet with abundant roots
< 1/16"
0819 0819S5 0819A EUTM-383243.892 NUTM-
4472018.345
Longitude-(-)112.375661730
Latitude-40.390586715
1B/ 22' - 41º Sandy silt, light gray, dry

6-24
Table 6.1-2. Soil Samples Collected for the 2005 EMFS (Continued)

Grid
ID
Sample
ID GPS/Name GPS Location Sector/Location Soil Description
0819B EUTM-383251.702 NUTM-
4472026.851
Longitude-(-)112.375571291
Latitude-40.40.390664423
1B/ 59',5" - 33º Sandy silt, brownish gray, dry with roots and other organics
0819C EUTM-383258.366 NUTM-
4472030.451
Longitude-(-)112.375493461
Latitude-40.390697779
1B/ 83',4" - 37º Sandy silt, brownish gray, dry with roots and other organics
0914 0914S5 0914A EUTM-384077.265 NUTM-
4466720.461
Longitude-(-)112.364882279
Latitude-40.342986826
8A/ 33',6" - 319º Fine silty sand/sandy silt brown, moist, good dilatancy,
abundant roots
0914B EUTM-384077.498 NUTM-
4466729.346
Longitude-(-)112.364881146
Latitude-40.343066884
8A/ 61',10" -
332º
Fine silty sand/sandy silt brown, moist, good dilatancy,
abundant roots
0914C EUTM-384069.292 NUTM-
4466736.244
Longitude-(-)112.364978989
Latitude-40.343127872
8A/ 92',4" - 320º Fine silty sand/sandy silt brown, moist, good dilatancy,
abundant roots
1004 1004S5 1004A EUTM-385242.061 NUTM-
4456755.754
Longitude-(-)112.349384541
Latitude-40.253397408
1B/ 22' - 37º Silty sand with F-M sub rounded gravel, abundant roots,
dark brown, very moist
1004B EUTM-385247.840 NUTM-
4456762.530
Longitude-(-)112.349317809
Latitude-40.253459229
1B/ 50' - 32º Silty sand with F-M sub rounded gravel, abundant roots,
dark brown, very moist

6-25
Table 6.1-2. Soil Samples Collected for the 2005 EMFS (Continued)

Grid
ID
Sample
ID GPS/Name GPS Location Sector/Location Soil Description
1004C EUTM-385251.631 NUTM-
4456768.081
Longitude-(-)112.349274244
Latitude-40.253509749
1B/ 73' - 26.5º Silty sand with F-M sub rounded gravel, abundant roots,
dark brown, very moist
1007 1007S5 1007A EUTM-385038.524 NUTM-
4459375.992
Longitude-(-)112.352247140
Latitude-40.276969634
1B/ 37',10" - 24º Silt with trace of fine sand; pebbles and cobbles rounded to
sub angular (20%) medium to dark brown
1007B EUTM-385043.084 NUTM-
4459378.408
Longitude-(-)112.352193953
Latitude-40.276992018
1B/ 53',8" - 34º Silt with trace of fine sand; pebbles and cobbles rounded to
sub angular (20%) medium to dark brown
1007C EUTM-385048.631 NUTM-
4459384.662
Longitude-(-)112.352129850
Latitude-40.277049109
1B/ 80',6" - 32º Silt with trace of fine sand; pebbles and cobbles rounded to
sub angular (20%) medium to dark brown
1009 1009S5 1009A EUTM-384999.484 NUTM-
4461598.544
Longitude-(-)112.353105419
Latitude-40.296982429
4B/ 21',5" - 175º Silt with sand (5%), pebbles sub angular (5%) medium to
light brown
1009B EUTM-385001.084 NUTM-
4461587.993
Longitude-(-)112.353084707
Latitude-40.296887623
4B/ 56',5" - 165º Silt with sand (5%), pebbles sub angular (5%) medium to
light brown
1009C EUTM-385000.846 NUTM-
4461577.993
Longitude-(-)112.353085706
Latitude-40.296797522
4B/ 90',3" - 166º Silt with trace of pebbles sub angular medium to light
brown

6-26
Table 6.1-2. Soil Samples Collected for the 2005 EMFS (Continued)

Grid
ID
Sample
ID GPS/Name GPS Location Sector/Location Soil Description
1011 1011S5 1011A EUTM-385038.568 NUTM-
4463653.424
Longitude-(-)112.353014984
Latitude-40.315495717
6B/ 30' - 264º Silt sand, fine, moist with abundant roots, brown
1011B EUTM-385030.368 NUTM-
4463654.016
Longitude-(-)112.353111578
Latitude-40.315499924
6B/ 60' - 263.5º Sandy silt, buff, dry with med sub rounded gravel
1011C EUTM-385020.438 NUTM-
4463651.617
Longitude-(-)112.353227986
Latitude-40.315476952
6B/ 92' - 254º Sandy silt, buff, dry
1013 1013S5 1013A EUTM-385080.008 NUTM-
4465629.839
Longitude-(-)112.352882796
Latitude-40.333302556
3B/ 24',2" - 123º Silt sand (5%), pebbles and cobbles (15%), medium brown
to gray
1013B EUTM-385087.996 NUTM-
4465625.931
Longitude-(-)112.352788075
Latitude-40.333268461
3B/ 50',7" - 116º Silt, trace sand, pebbles and cobbles (20%), medium
brown to gray
1013C EUTM-385091.713 NUTM-
4465617.671
Longitude-(-)112.352742843
Latitude-40.333194573
3B/ 77',8" - 121º Silt, trace sand, pebbles and cobbles (10%), medium
brown to gray
1015 1015S5 1015A EUTM-385064.970 NUTM-
4467622.656
Longitude-(-)112.353418494
Latitude-40.351249290
6A/ 24',6" - 241º Gravelly silty sand, fine buff brown moist, gravel sub
angular to sub rounded up to 2"

6-27
Table 6.1-2. Soil Samples Collected for the 2005 EMFS (Continued)

Grid
ID
Sample
ID GPS/Name GPS Location Sector/Location Soil Description
1015B EUTM-385055.771 NUTM-
4467617.621
Longitude-(-)112.353525876
Latitude-40.351202675
6A/ 57',6" - 232º Gravelly silty sand, fine buff brown moist, gravel sub
angular to sub rounded up to 2"
1015C EUTM-385046.174 NUTM-
4467617.771
Longitude-(-)112.353638889
Latitude-40.351202707
6A/ 88',4" - 240º Gravelly silty sand, fine buff brown moist, gravel sub
angular to sub rounded up to 2"
1018 1018S5 1018A EUTM-385128.388 NUTM-
4470746.486
Longitude-(-)112.353234544
Latitude-40.379393477
3B/ 35' - 120º Fine silty sand with trace fine sub angular to sub rounded
gravel, brown wet
1018B EUTM-385134.863 NUTM-
4470741.849
Longitude-(-)112.353157454
Latitude-40.379352606
3B/ 60' - 117º Gravelly silty sand fine, gravel is fine and angular (15%),
brown, wet
1018C EUTM-385138.159 NUTM-
4470737.206
Longitude-(-)112.353117798
Latitude-40.379311234
3B/ 80' - 122º Silty sand fine, brown , wet trace fine gravel
1022 1022S5 1022A EUTM-385030.568 NUTM-
4474624.662
Longitude-(-)112.355086805
Latitude-40.414309392
1B/ 16',10" - 34º Silty sandy gravel F-C with cobbles and boulders, buff, dry,
abundant root hairs
1022B EUTM-385041.423 NUTM-
4474633.406
Longitude-(-)112.354960485
Latitude-40.414389646
1B/ 60',3" - 38º Silty sandy gravel F-C with cobbles and boulders, buff, dry,
abundant root hairs

6-28
Table 6.1-2. Soil Samples Collected for the 2005 EMFS (Continued)

Grid
ID
Sample
ID GPS/Name GPS Location Sector/Location Soil Description
1022C EUTM-385045.704 NUTM-
4474642.866
Longitude-(-)112.354911746
Latitude-40.414475444
1B/ 93' - 28º Silty sandy gravel F-C with cobbles and boulders, buff, dry,
abundant root hairs
1108 1108S5 1108A EUTM-386126.663 NUTM-
4460756.701
Longitude-(-)112.339696625
Latitude-40.289554387
1B/ 31',9" - 44º Silt trace of sand, pebbles sub angular to rounded (5-10%),
medium brown
1108B EUTM-386127.734 NUTM-
4460760.909
Longitude-(-)112.339684780
Latitude-40.289592438
1B/ 43',4" - 32º Silt trace of sand, pebbles sub angular to rounded (5-10%),
medium brown
1108C EUTM-386134.831 NUTM-
4460762.927
Longitude-(-)112.339601667
Latitude-40.289611581
1B/ 65',5" - 42º Silt trace of sand, pebbles sub angular to rounded (15%),
medium brown
1202 1202S5 1202A EUTM-387025.267 NUTM-
4454654.687
Longitude-(-)112.328052099
Latitude-40.234715676
8B/ 15',2" - 346º Silt with small sub angular pebbles, medium brown
1202B EUTM-387026.012 NUTM-
4454660.925
Longitude-(-)112.328044448
Latitude-40.234771959
8B/ 35',6" - 354º Silt with small sub angular pebbles, medium brown
1202C EUTM-387028.793 NUTM-
4454664.696
Longitude-(-)112.328012426
Latitude-40.234806300
8B/ 48',4" -
359.5º
Silt with small sub angular pebbles, medium brown

6-29
Table 6.1-2. Soil Samples Collected for the 2005 EMFS (Continued)

Grid
ID
Sample
ID GPS/Name GPS Location Sector/Location Soil Description
1209 1209S5 1209A EUTM-387436.154 NUTM-
4460982.584
Longitude-(-)112.324334373
Latitude-40.291766244
1B/ 33',4" - 25º Clayey silt; loose no plasticity, minimal pebbles, sub
angular, medium brown
1209B EUTM-387442.758 NUTM-
4460983.921
Longitude-(-)112.324256931
Latitude-40.291779177
1B/ 51',6" - 40º Clayey silt, some sand (5%), pebbles and cobbles, sub
angular (10%), medium to dark brownish gray, low
plasticity
1209C EUTM-387447.791 NUTM-
4460989.878
Longitude-(-)112.324198776
Latitude-40.291833503
1B/ 77',3" - 36º Silt with sand (5%), clay (5%), pebbles and cobbles (10%),
medium brown to gray, no plasticity
1214 1214S5 1214A EUTM-387534.568 NUTM-
4466232.054
Longitude-(-)112.324100188
Latitude-40.339060943
1B/ 23',6" - 30º Sandy silt/silty sand, brown moist with abundant grass
roots
1214B EUTM-387541.862 NUTM-
4466239.111
Longitude-(-)112.324015573
Latitude-40.339125494
1B/ 56' - 32º Sandy silt/silty sand, brown moist with abundant grass
roots
1214C EUTM-387548.525 NUTM-
4466246.548
Longitude-(-)112.323938460
Latitude-40.339193372
1B/ 88',2" - 30º Sandy silt/silty sand, brown moist with abundant grass
roots
1218 1218S5 1218A EUTM-386779.720 NUTM-
4470344.474
Longitude-(-)112.333714801
Latitude-40.375998627
1B/ 32' - 34º Clayey silt, little to no plasticity, loose, with sub angular to
angular pebbles and cobbles, medium brown to gray

6-30
Table 6.1-2. Soil Samples Collected for the 2005 EMFS (Continued)

Grid
ID
Sample
ID GPS/Name GPS Location Sector/Location Soil Description
1218B EUTM-386784.990 NUTM-
4470350.450
Longitude-(-)112.333653804
Latitude-40.376053169
1B/ 58' - 33º Clayey silt, no plasticity, loose, with sub angular to angular
pebbles and cobbles, medium brown to gray
1218C EUTM-386790.834 NUTM-
4470356.585
Longitude-(-)112.333586074
Latitude-40.376109217
1B/ 86' - 32.5º Clayey silt, little to no plasticity, loose, with occasional
angular to sub angular pebbles and cobbles, medium
brown
1222 1222S5 1222A EUTM-387089.750 NUTM-
4474700.868
Longitude-(-)112.330836064
Latitude-40.415277636
3A/ 24' - 100º Silt with (5%) sand, pebbles and cobbles (15%), medium
brown to gray
1222B EUTM-387099.417 NUTM-
4474699.459
Longitude-(-)112.330721901
Latitude-40.415266257
3A/ 55' - 94º Silt with (5%) sand, pebbles and cobbles (15%), medium
brown to gray
1222C EUTM-387107.888 NUTM-
4474694.699
Longitude-(-)112.330621232
Latitude-40.415224541
3A/ 86',8" - 98º Silt with (5%) sand, pebbles and cobbles (15%), medium
brown to gray
1223 1223S5 1223A EUTM-386883.659 NUTM-
4474864.622
Longitude-(-)112.333293678
Latitude-40.416724538
1B/ 29',10" - 25º Silt with (10%) sand, pebbles and cobbles (10%), medium
brown to light gray
1223B EUTM-386890.098 NUTM-
4474873.624
Longitude-(-)112.333219406
Latitude-40.416806499
1B/ 66',1" - 25º Silt with sand (trace), pebbles and cobbles (25%), medium
brown to gray

6-31
Table 6.1-2. Soil Samples Collected for the 2005 EMFS (Continued)

Grid
ID
Sample
ID GPS/Name GPS Location Sector/Location Soil Description
1223C EUTM-386896.300 NUTM-
4474877.835
Longitude-(-)112.333147072
Latitude-40.416845266
1B/ 89',9": - 30º Silt with (5%) sand, pebbles and cobbles (30%), medium
brown to gray
1305 1305S5 1305A EUTM-388122.487 NUTM-
4457501.760
Longitude-(-)112.315653676
Latitude-40.260506634
1B/ 22',4" - 32º Silt sand (30%) sand is F-C sub rounded to sub angular,
brown , moist
1305B EUTM-388129.078 NUTM-
4457508.164
Longitude-(-)112.315577311
Latitude-40.260565193
1B/ 52' - 33º Silt sand (30%) sand is F-C sub rounded to sub angular,
brown , moist
1305C EUTM-388137.391 NUTM-
4457513.153
Longitude-(-)112.315480440
Latitude-40.260611245
1B/ 81',8" - 37º Silt sand (30%) sand is F-C sub rounded to sub angular,
brown , moist
1412 1412S5 1412A EUTM-388826.342 NUTM-
4464707.853
Longitude-(-)112.308630144
Latitude-40.325505661
7A/ 17' - 282º Silty clay/clayey silt, with pebbles and cobbles sub angular,
medium brown, low plasticity, loose
1412B EUTM-388819.062 NUTM-
4464710.537
Longitude-(-)112.308716288
Latitude-40.325528861
7A/ 43' - 280º Clayey silt, with pebbles, sub angular to rounded, medium
brown, loose, low to no plasticity
1412C EUTM-388809.477 NUTM-
4464714.211
Longitude-(-)112.308829720
Latitude-40.325560676
7A/ 76' - 280.5º Clayey silt, with pebbles, some cobbles, medium brown,
loose, no plasticity

6-32
Table 6.1-2. Soil Samples Collected for the 2005 EMFS (Continued)

Grid
ID
Sample
ID GPS/Name GPS Location Sector/Location Soil Description
1416 1416S5 1416A EUTM-389395.113 NUTM-
4468148.323
Longitude-(-)112.302532698
Latitude-40.356569294
1B/ 41',2" - 31º Clayey gravelly, silty sand, gravel to 2" diameter, sub
angular to sub rounded, one sub angular cobble 4"
1416B EUTM-389399.790 NUTM-
4468152.969
Longitude-(-)112.302478431
Latitude-40.356611759
1B/ 64' - 33º Silty gravelly sand, gravel to 2" sub angular to sub rounded
1416C EUTM-389404.541 NUTM-
4468156.096
Longitude-(-)112.302423046
Latitude-40.356640562
1B/ 83',11" - 35º Gravelly silty sand, gravel to 1" sub angular to sub
rounded, sand is fine to course sub angular to sub rounded
1508 1508S5 1508A EUTM-390105.462 NUTM-
4460699.416
Longitude-(-)112.292888524
Latitude-40.289570909
1A/ 23' - 14º Silt with small about of clay, occasional pebbles and
cobbles angular to sub angular (15%) medium brown to
light gray
1508B EUTM-390106.252 NUTM-
4460707.354
Longitude-(-)112.292880591
Latitude-40.289642511
1A/ 47',10" - 4º Silt with small about of clay, occasional pebbles and
cobbles angular to sub angular (20%) medium brown to
light gray
1508C EUTM-390114.502 NUTM-
4460718.165
Longitude-(-)112.292785416
Latitude-40.289740967
1A/ 91',3" - 13º Clayey silt, loose, no plasticity some pebbles and cobbles
angular to sub angular (5%) medium brown to light gray
1706 1706S5 1706A EUTM-392171.522 NUTM-
4458554.624
Longitude-(-)112.268226334
Latitude-40.270521472
1B/ 18',11" - 34º Silt, and fine sand (30%), medium brown

6-33
Table 6.1-2. Soil Samples Collected for the 2005 EMFS (Continued)

Grid
ID
Sample
ID GPS/Name GPS Location Sector/Location Soil Description
1706B EUTM-392178.165 NUTM-
4458563.497
Longitude-(-)112.268149714
Latitude-40.270602256
1B/ 55',6" - 29º Silt, and fine sand (30%), medium brown
1706C EUTM-392182.734 NUTM-
4458568.321
Longitude-(-)112.268096804
Latitude-40.270646287
1B/ 76',3" - 30º Silt, and fine sand (30%), medium brown
1710 1710S5 1710A EUTM-392257.555 NUTM-
4462249.389
Longitude-(-)112.267836437
Latitude-40.303811846
1B/ 28',5" - 30º Silty sand with F-C gravel, sand is F-C poorly graded, sub
rounded to sub angular with cobbles and boulders
1710B EUTM-392265.792 NUTM-
4462251.924
Longitude-(-)112.267739953
Latitude-40.303835736
1B/ 55' - 44º Silty sand with F-C gravel, sand is F-C poorly graded with
angular to sub angular with gravel and cobbles, wet
1710C EUTM-392269.060 NUTM-
4462261.286
Longitude-(-)112.267703080
Latitude-40.303920486
1B/ 81',25" - 33º Silty sand with F-C gravel, sand is F-C poorly graded with
angular to sub angular with gravel and cobbles, wet
1808 1808S5 1808A EUTM-393015.841 NUTM-
4460689.370
Longitude-(-)112.258654713
Latitude-40.289857937
5A/ 42' - 188º Clayey silt, loose, no plasticity, with (50%) angular to sub
angular pebbles, and cobbles, occasional boulders,
medium brown to gray
1808B EUTM-393011.677 NUTM-
4460683.200
Longitude-(-)112.258702659
Latitude-40.289801828
5A/ 67' - 191º Clayey silt, loose, no plasticity, with pebbles and cobbles
angular to sub angular, medium brown to gray

6-34
Table 6.1-2. Soil Samples Collected for the 2005 EMFS (Continued)

Grid
ID
Sample
ID GPS/Name GPS Location Sector/Location Soil Description
1808C EUTM-393008.053 NUTM-
4460677.948
Longitude-(-)112.258744408
Latitude-40.289754060
5A/ 89' - 192º Clayey slit with sand (20%), loose, no plasticity with
pebbles and cobbles angular and sub angular, medium
brown to gray

Notes:

GPS = Global Positioning System
ID = identification

6-35
Table 6.2-1. Plant Species List

Code Scientific Name Common Name LF D NA DI F 1996 1998 1999 2002 2005
AGDE(CR) Agropyron desertorum Wheatgrass G P A 1 1 X X X X X
AGEX Agrostis exarata Spike bentgrass G P N 1 1 X X
AGRE Agropyron repens Quackgrass G P A 3 2 X
AGSU Agropyron subsecundum Bearded wheatgrass G P N 1 1 X X X
AGTR Agropyron trachycaulum Slender wheatgrass G P N 1 1 X X X X
ALAL Allyssum alyssoides Yellow allyssum F A/B A 3 3 X X X
ALGE Allium geyeri Geyer onion F P N 2 3 X
ALsp Allium sp. Onion F P u 2 3 X
ARDE Arabis demissa Low rockcress F P N 2 3 X
ARFE Arenaria fendleri Fendler sandwort L P N 2 2 X X
ARFR Artemisia frigida Fringed sagebrush L P N 2 3 X X
ARTR Artemisia tridentata Big sagebrush L P N 2 3 X X X X X
ASBE Astragalus beckwithii Beckwith’s milkvetch F P N 2 4 X
ASNE Astragalus newberryi Newberry’s milkvetch F P N 2 4 X
ASGE Astragalus geyeri Geyer milkvetch F P N 2 4 X
ATCA Atriplex canascens Four-wing saltbush S P N 1 1 e X X X
ATCO Atriplex confertifolia Shadscale S P N 2 1 X X X X X
BRTE Bromus tectorum Cheatgrass G A A 3 2 X X X X X
CAANF Castilleja chromosa Desert paintbrush F P N 2 2 X
CADR Cardaria draba Whitetop F P A 3 3 X X
CELA Ceratoides lanata Winterfat S P N 1 1 X X X
CELO Cenchrus longispinus Longspine sandbur G A A 3 3 X X X X
CHDO Chaenactis douglasii Douglas’ Dusty Maiden F B/P N 2 3 X
CHNA Chrysothamnus nauseosus Grey rabbitbrush S P N 1 1 X X X X X
CHRU Chenopodium rubrum Red goosefoot F A N 2 3 pu X X
CHTE2 Chorispora tenella Purple crossflower F A A 3 3 X
CHVI Chrysothamnus viscidiflorus Douglas rabbitbrush S P N 3 3 X

6-36
Table 6.2-1. Plant Species List (Continued)

Code Scientific Name Common Name LF D NA DI F 1996 1998 1999 2002 2005
CRNA Cryptantha nana Little cryptantha S P N 3 2 X
CRsp Cryptantha sp. Unknown cryptantha P P u u u X X
DEPI Descurainia pinnata Pinnate tansy mustard F A N 3 3 X X
DESO Descurainia sophia Flixweed F A A 3 3 X X
DIST(p) Distichlis stricta Desert saltgrass G P N 2 2 e X X X
ELTA Elymus trachycaulus Slender wheatgrass G P N 1 1 X
ELTR Elymus triticoides Beardless wild rye G P N 1 2 X X X X
EPVI Ephedra sp. Mormon tea S P N 2 2 X
ERCI Erodium cicutarium Redstem fileree F A/B A 3 3 X X X
EROV Eriogonum ovalifolium Cushion buckwheat F P N 2 3 X X
ERPU Erigeron pumilus Low fleabane F P N 3 2 X
ERsp Erigeron sp. Wild buckwheat F u u u X
ERUM Erigognum umbellatum Sulfur buckwheat F P N 2 3 X
ERYSI Erysimum captatum Wallflower F P N 3 3 X
EUBR Euphorbia brachycera Shorthorn spurge F P N 3 1 X X X
FEsp Festuca sp. Fescue G u u u X
GICO Gilia congesta Ball-head gilia F P N 3 2 X X X X
GUSA Gutierrezia sarothrae Broom snakeweed S P N 2 4 X X X X
HAGL Halogeton glomeratus Halogeton F A A 3 3 X
HOJU Hordeum jubatum Foxtail barley G P N 3 3 X
JUAR Juncus articus Wiregrass R P N 2 3 e e X
JUBU Juncus bufonius Toad rush R A N 2 3 X
JUNE Juncus nevadensis Nevada rush R P N 2 3 X
JUOS Juniperus osteosperma Utah juniper T P N 2 3 X X X X X
KRLA2 Ceratoides lanata Winterfat S P N 1 1 X
LASE Lactuca serriola Prickly lettuce F A/B A 3 3 X X X
LEFE Lesquerella sp Bladderpod F P N 3 3 X

6-37
Table 6.2-1. Plant Species List (Continued)

Code Scientific Name Common Name LF D NA DI F 1996 1998 1999 2002 2005
LEKI Lesquerella kingii King’s bladderpod F P N 2 3 X
LELA Lepidium latifolium Perennial peppergrass F P A 3 2 X X X
LEPE Lepidium perfoliatum Shield peppergrass F A A 3 2 X X X X X
LOPE Lolium perenne Perrenial ryegrass G A A 3 3 X
OECA Oenethera caespitosa Desert evening-primrose F P N 3 4 X
OPPA(O) Opuntia polyacantha Plains pricklypear F P N 2 3 X X X X
ORHE Oryzopsis hymenoides Indian rice grass G P N 1 1 X X X X X
PHHO Phlox hoodii Hood’s phlox M P N 3 3 X
PHLO Phlox longifolia Long-leaved phlox F P N 3 3 X X
PIED Pinus edulis Pinyon pine T P N 2 3 X
POCU Poa cusickii Cusick’s bluegrass G P N 1 1 X X
POEP Poa epilis Skyline bluegrass G P N 1 1 X X
POFE Poa fendeleriana Mutton grass G P N 1 1 X
PORA Polygonum ramosissimum Bushy knotweed F A N 3 3 X X
POSE Poa secunda Sandberg bluegrass G P N 2 1 X X X X X
RATE Ranunculus testiculatus Bur buttercup F A A 3 3 e e X X X
RUOC Rudbeckia occidentalis Western coneflower F P N 2 2 X
SAIB Salsola iberica Russian thistle F A A 3 2 X X
SAVI Sarcobatus virmiculatus Greasewood S P N 2 4 X X X X
SERI Senecio riddelli Riddell’s groundsel F P N 3 4 X X
SIAL2 Sisymbrium altissimum Tumble mustard F A A 3 3 X X X X
SIHY Sitanion hystrix Squirreltail G P N 2 2 X X X X X
SPCO Sphaeralcea coccinea Scarlet globemallow F P N 2 2 X X X X
SPGR Sphaeralcea grossularifolia Gooseberry-leaf
globemallow
F P N 2 2 X
STCM Stipa comata Needle-and-thread G P N 1 1 X X
STCO Stipa columbiana Columbia needlegrass G P N 1 1 X X

6-38
Table 6.2-1. Plant Species List (Continued)

Code Scientific Name Common Name LF D NA DI F 1996 1998 1999 2002 2005
STCR Streptanthus cordatus Heartleaf twistflower F B/P N 3 2 X
TAOF Taraxacum officinale Dandelion F P A 3 1 X
TENU Tetradymia nuttalli Nuttal’s horsebrush L P N 2 4 X X X
THIN Thelypodium intergrifolium Whole-leaf mustard F B/P N 2 3 pu x x
TRDU Tragopogon dubius Western salsify F A/B A 3 2 X X
TRRE Trifolium repens White clover F P A 1 1 X
UCsp Unknown crucifera sp. Unknown F u u u X
Unsp Unknown sp. Unknown F u u u X
VIAM Vicia americana American vetch F P N 1 2 X X X X
YAST Yellow Atragalus spp. Yellow astragalus spp. F u 3 2 X
ZIPA Zigadenus paniculatus Foothill death-camas F P N 2 4 X
ZIVE Zigadenus venenosus Watson’s death-camas F P N 2 4 X
Total 59 44 50 17 42

Notes:

LI = life form D = duration NA = nativity DI = decreaser/increaser index
F= forb A = annual A = alien 1 = decreaser
G = grass B = biennial N = native 2 = increaser
L = low shrub P = perennial u = unknown 3 = invader
M = mat former u = unknown
R = graminoide
S = shrub
T = tree

F = forage value 1996/1998/1999/2002 = Year Observed
1 = good X = observed
2 = fair e = erroneously identified as another species in original field work
3 = poor u = unknown
4 = poisonous

6-39
Table 6.2-2. Shrub Community Composition

6-40
Table 6.2-2. Shrub Community Composition (Continued)

6-41
Table 6.2-2. Shrub Community Composition (Continued)

Notes:
a Refer to table 6.2-1 for species names that go with the codes in this table.

m2/ha = square meter per hectare

6-42
Table 6.2-3. Herbaceous Community Composition 1
2

6-43
Table 6.2-3. Herbaceous Community Composition (Continued) 1
2

6-44
Table 6.2-3. Herbaceous Community Composition (Continued) 1
2

6-45
Table 6.2-3. Herbaceous Community Composition (Continued)

Notes:

a Refer to table 6.2-1 for species names to go with the codes.

D/I Index = decreaser/increaser index
FV = forage value

6-46
Table 6.3-1. Summary of 2005 Vegetation Characteristics

6-47
Table 6.3-1. Summary of 2005 Vegetation Characteristics (Continued)

6-48
Table 6.3.2.1-1. Herbaceous Vegetation Comparison 1996 Through 2005

EMBS 1996 1999 EMFS 2002 EMFS 2005 EMFS
Speciesa % Cover IV FV Speciesa % Cover IV FV Speciesa % Cover IV FV Speciesa % Cover IV FV
CELO 35.45 0.275 1 BRTE 33.70 0.172 2 RATE 1.17 0.329 3 RATE 16.59 0.228 3
BRTE 21.63 0.198 2 DISP(p) 3.77 0.015 2 BRTE 0.91 0.289 2 BRTE 14.68 0.211 2
ORHE 14.66 0.146 1 RATE 3.11 0.075 3 DIST(p) 0.49 0.094 2 DESO 4.41 0.090 3
POCU 3.74 0.027 1 ORHE 1.41 0.052 1 AGDE(CR) 0.28 0.062 1 LEPE 2.85 0.056 2
LEPE 2.69 0.044 2 ALAL 1.30 0.037 3 ORHE 0.16 0.070 1 1(3)b 1.32 0.015 (3)
SIHY 1.57 0.037 2 POSE 1.11 0.045 1 SIHY 0.07 0.043 2 CADR 1.25 0.040 3
ARFE 1.52 0.024 2 SIHY 1.06 0.097 2 ALAL 0.05 0.047 3 ALAL 0.92 0.035 3
SYAL 1.42 0.040
3
VIAM 0.84 0.015
2
POSE 0.05 0.021
1
AGDE(C
R)
0.78 0.023
1
POSE 1.33 0.017 1 SYAL 0.82 0.037 3 LEPE 0.04 0.012 2 CELO 0.62 0.028 3
DEPI 0.72 0.014 3 ELTR 0.81 0.007 2 VIAM 0.03 0.017 2 AGTR 0.62 0.020 3

Sum 84.73 0.822 47.92 0.551 3.26 0.984 44.05 0.746
Total
Cover, All
Species
88.93 1.0 54.08 1.0 3.27 1.0 49.35 1.0
Number
of
Species
59 50 17 42

Notes:

a See table 6.2-1 for definitions of species codes.
b 1(3) = unknown, tentatively identified as DIST(p), Distichlis stricta in which case FV would be changed to 2, fair.

IV = importance value
FV = forage value:
1 = good 2 = fair
3 = poor (3) = assumed poor forage value for unknown species

6-49
Figure 6.2-1. Dominant Shrub Species

6-50
Figure 6.2-2. Percent Shrub Coverage Map and Relative Dominance Distribution

6-51
Figure 6.2-3. Dominant Herb Species

6-52
Figure 6.2-4. Percent Herbaceous Coverage Map and Relative Dominance Distribution

6-53
Figure 6.3-1. Clumps Per Hectare Histogram Chart (Shrubs)

6-54
Figure 6.3-2. Average Height Classification Histogram Chart (Shrubs)

6-55
Figure 6.3-3. Areal Coverage Per Hectare Histogram Chart (Shrubs)

6-56
Figure 6.3-4. Percent Total Vegetation Coverage Map

7-1
SECTION 7
CHEMICAL RESULTS – GENERAL

This section contains information pertaining to development of chemical analytical
results reported in sections 8 through 11.

7.1 Chemical Data Assessment

This section provides an assessment of the technical quality and validity of
the 2005 EMFS chemical data. Comparability of the 2005 EMFS chemical data with the
previous studies was discussed in section 5 of this report. Validation results for data
obtained from analysis of the samples collected during both the May 2005 and the
June 2005 events are discussed in the 2005 Data Validation Letter Report for
Environmental Monitoring Follow-on Study. Laboratory data reports are provided in
appendix C of this report.

In general, the overall chemical data derived from the 2005 EMFS were found to be
acceptable and useable for the purposes of this study. Use of the chemical data for
comparison to the previous studies is considered technically acceptable.

Samples of environmental media were collected from 41 sites in May 2005 and from
four sites in June 2005. All sampling activities were conducted in accordance with the
approved Final FSP dated October 2004. The samples were submitted to ELAB and
Paradigm Laboratories, Inc. (Southwest Laboratories of Oklahoma, Inc. [SWLOK]) for
chemical analyses. Both laboratories maintain current State of Utah certifications for all
analyses required for this 2005 EMFS. ELAB was contracted to perform all analyses
required for this project with the exception of dioxins and furans. Paradigm
Laboratories, Inc. performed only the dioxin and furan analyses for all matrices.

In order to promote data comparability, the analytical laboratories were required to
perform testing within the guidelines of standardized USEPA-approved protocols. All

7-2
analyses were performed in strict accordance with the following protocols, unless
otherwise noted: Test Methods for Evaluating Solid Waste, SW-846, 3rd Edition,
(USEPA, 1997) The laboratories were required to report field sample and supporting
QC data in a USEPA Level 4 format consistent with the current USEPA Contract
Laboratory Program Statement of Work (SOW). Level 4 laboratory data packages
include all forms, summaries, and raw data specified in the USEPA Contract Laboratory
Program SOW. The Level 4 data packages are sufficient to recreate the analytical
process for full data validation. Scanned and indexed data will be uploaded to the
Environmental Restoration Information System (ERIS) database.

7.1.1 Chemical Data Validation Results. The quality of the chemical data was
evaluated following procedures included in the QAPjP. As reported in the 2005 Data
Validation Letter Report for Environmental Monitoring Follow-on Study, the quality
assurance/quality control (QA/QC) results associated with the 2005 EMFS data
generally indicate that the data met “definitive data” standards and were of known
quality. QC data demonstrated that the quality assurance (QA) mechanisms were
effective in ensuring measurement data reliability within expected limits of sampling and
analytical error. The data, as qualified, are considered representative of site conditions
at the time sampled. Data reported are acceptable for the uses as intended with the
required qualifications and limitations.

One semivolatile target analyte, hexachlorocyclopentadiene, is the only analyte with
unusable data due to QC deficiencies. Five soil samples and fifteen vegetation samples
required rejection for hexachlorocyclopentadiene. Rejected results were not included in
statistical evaluation of the 2005 EMFS data. The rejected hexachlorocyclopentadiene
results were not anticipated to have a significant effect on project decision-making.
Data users are urged to review the data quality narratives and associated data
qualifications found in the 2005 Data Validation Letter Report for Environmental
Monitoring Follow-on Study before utilizing this data for decision-making.

The approved chemical data quality review procedures were based on EPA Contract
Laboratory Program National Functional Guidelines for Organic Data Review,

7-3
EPA-540/R-99/008 (October 1999), EPA Contract Laboratory Program National
Functional Guidelines for Inorganic Data Review, EPA-540/R-94/013 (February 1994),
and USEPA Analytical Operations/Data Quality Center National Functional Guidelines
for Chlorinated Dioxin/Furan Data Review, EPA 540-R-02-003 (August 2002), herein
collectively referred to as the Functional Guidelines. Data evaluations also were based
on the QC requirements of the analytical methods, project data quality objectives
(DQOs) presented in the QAPjP, and informed professional judgment of the evaluator.
Data validation was performed by qualified personnel, experienced in the evaluation of
analytical data quality.

7.2 Statistical Approach

A statistical evaluation of the 2005 EMFS chemical data derived from surface soil and
vegetation samples was performed to identify statistically significant increases in the
mean concentration for any monitored chemical parameter relative to the baseline mean
values from the 1996 EMBS. The statistical evaluation was performed in accordance
with the procedures presented in Section 6 of the TOCDF FSP.

Three statistical approaches were used to evaluate the 2005 EMFS data. The first
approach was consistent with the procedures used in the 1999 and 2002 EMFS. Data
from the original 26 sampling sites, plus two sites added for the 2002 EMFS, were
compared to the data from the 1996 EMBS. All data from site 0707 were eliminated
from the statistical evaluation as indicated in the EMBS because of the anomalous
ecological nature of the site. Shrub data from site 1022 were also excluded from the
statistical evaluations because big sagebrush was not found at this site and was the
only shrub sampled at all other sites. No samples were collected at site 0224 in 2005
because access permission was not obtained from the landowner. EMBS site 0112
was permanently moved approximately one-half mile and reestablished as site 0111 for
the 2005 EMFS. Based on these adjustments, statistical evaluation included data from
23 soil, 22 shrub and 22 herbaceous samples from each of the EMBS and the
2005 EMFS. It has been referred to as the “random-sample (matched)” statistical
approach in this document.

7-4
The second approach was also consistent with the 1999 and 2005 EMFS as described
previously, but included data from the 16 new sampling sites added for the 2005 EMFS.
This evaluation helped determine if the new sampling sites are statistically consistent
with the sites chosen for the EMBS, or if their inclusion in the statistical evaluations
would bias the 2005 EMFS results. This statistical evaluation included data from
25 EMBS soil, 41 EMFS soil, 24 EMBS shrub, 39 EMFS shrub, 24 EMBS herbaceous
and 41 EMFS herbaceous samples. It has been referred to as the “random-sample
(all)” statistical approach in this document.

The third approach used paired-sample statistical methods. All previous studies,
including the EMBS, assumed a statistically random sampling pattern for both the
EMBS and for each EMFS. However, as discussed in Section 6 of the TOCDF FSP, it
can be argued that the data are more appropriately evaluated using paired-sample
statistical methods since the EMFS samples are collected at the same sites as the
EMBS samples. Using a paired-sample approach allows for evaluation of data from
sites 0707 and the shrub data from location 1022 because only paired differences are
evaluated. Variations in concentrations from site to site are eliminated using
paired-sample statistical methods. The third statistical evaluation included the data
from 24 soil, 23 shrub, and 23 herbaceous samples from the EMBS and the
2005 EMFS. It has been referred to as the “paired-sample” statistical approach in this
document.

The statistical evaluation process began by defining the condition to be tested, the null
hypothesis. The null hypothesis was evaluated for validity for each COPC in the EMFS
using a tiered approach. The null hypothesis is summarized as follows:

The average concentration observed during follow-on monitoring for each
COPC in each medium is less than or equal to the mean concentration
observed for that COPC in that medium during baseline monitoring.

If an individual COPC was found to have sufficient evidence to reject the null
hypothesis, it was retained for historical trend and spatial distribution evaluation.

7-5
COPCs for which the null hypothesis was not rejected were eliminated from further
evaluation. The following summarizes the statistical approach applied to 2005 EMFS
chemical data. For additional information concerning each step, see Section 6 of the
FSP.

Step 1. Determine the frequency of detection for each COPC in 2005 EMFS and EMBS
and identify an appropriate distribution evaluation method based on detection
frequency.

Step 2. Determine the distribution for each COPC in each medium using the distribution
test identified in step 1.

a. The Shapiro-Wilk test (data sets of less than 50 samples) was applied for
COPCs with 85 to 100 percent frequency of detection. In this test any
nondetect values were substituted with one-half the MDL.

b. The Shapiro-Wilk test also was applied for COPCs with 50 to 85 percent
frequency of detection; however, nondetect values were estimated in this
test using the linear regression technique known as regression on order
statistics (ROS) developed by Helsel (Helsel, 1990).

c. A nonparametric distribution was assumed for COPCs with a
10 to 50 percent frequency of detection.

d. A Poisson distribution, which is descriptive of a rare event, was assumed
for COPCs with less than 10 percent frequency of detection.

Step 3. Determine maximum detected value and estimate summary statistics (mean
and standard deviation) for each COPC in each medium based on the appropriate
distribution.

7-6
Step 4. Compare 2005 EMFS summary statistics to EMBS screening levels:

a. Compare 2005 EMFS detected values to the EMBS 99 percent UTL.

b. Compare 2005 EMFS mean values to EMBS mean values.

c. Compare 2005 EMFS summary statistics to EMBS maximum detected
value (for those COPCs with an insufficient number of EMBS detections to
establish a UTL).

d. Compare 2005 EMFS summary statistics to EMBS reporting limits (for
those COPCs where there were no detections in the EMBS).

Retain for further evaluation those COPCs where the 2005 EMFS statistic exceeds the
EMBS screening level.

Step 5. Perform appropriate statistical tests based on data distribution (step 2) to
determine if the compared means are statistically the same, different, or indeterminate.

a. If EMFS and EMBS data both follow a parametric distribution (normal or
log normal) evaluate using a random-sample t-test. A paired-sample t-test
was used to compare the differences between paired samples from the
EMFS and EMBS (samples collected at the same sampling locations).

b. If the random sample data set distributions for the EMBS and EMFS were
not similar or if either data set demonstrated a nonparametric distribution,
the Wilcoxon Rank-Sum (WRS) test was used. For nonparametric data
sets, paired samples were compared using the Wilcoxon Signed-Rank
(WSR) test, Paired Prentice-Wilcoxon (Pt) Test, or Sign Test. The test
used was based on frequency of detection and the number of censoring
levels.

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c. If either the EMBS or EMFS data set had fewer than 10 percent
detections, a Poisson model was used to compare the data sets.
Significant differences in reporting limits between the EMBS and EMFS
may preclude use of the Poisson model. In such cases, a direct
comparison of the detected values and reporting limits for nondetects will
be used when a Poisson model cannot be used.

Retain for further evaluation those COPCs where there was a statistically significant
increase in concentration from the EMBS to the 2005 EMFS.

Step 6. Evaluate spatial and temporal trends. Spatial trends were evaluated by
mapping 2005 EMFS data. Temporal trends were evaluated by preparing a histogram
showing COPC values from the EMBS and each EMFS.

Statistical testing of the null hypothesis for this study led to one of three outcomes:

a. Accept Null Hypothesis. 2005 EMFS data show no statistically significant
increase in COPC mean concentrations relative to the EMBS baseline
mean.

b. Reject Null Hypothesis. 2005 EMFS data show a statistically significant
increase in COPC mean concentrations relative to the EMBS baseline
mean concentrations.

c. Statistically Indeterminate. Comparison of 2005 EMFS and EMBS data is
inconclusive or not applicable. An indeterminate decision can result from
differing detection limits between the two studies, COPC detection in the
2005 EMFS but not in the EMBS, inconclusive or contradictory statistical
test results.

The analytical results for site 0707 were excluded from the random-sample (matched)
statistical evaluation to remain consistent with the EMBS and follow-on studies. The

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site is located in a salt marsh. As in the previous studies, the soil samples were found
to have anomalously high values for many of the analytes tested. The analytical results
for site 0707 were included in the paired-sample statistical evaluations.

Common laboratory contaminants were excluded from historical trend and spatial
distribution analyses in the 2005 EMFS to remain consistent with the EMBS.