Associates Inc."
SUPPLEMENTARY GUIDANCE
ON CONDUCTING USE
ATTAINABILITY ANALYSES
ON EFFLUENT
DEPENDENT ECOSYSTEMS
Prepared for
Water Quality Branch
EPA Region K
llth Floor
75 Hawthorne Street
San Francisco, CA 94105
Prepared by:
Abt Associates
55 Wheeler Street
Cambridge, MA 02J38
TetnTeeb
3746 Moont Diablo Blvd.
Suite 300
Lafayette, CA 94549
March 1993
55 Wheeler Strew Cambridge, Massachusetts 02138-1168 (617)492-7100 Fax: (617) 492-5219 TDD (617) 354-6618
-------
Associates Inc."
SUPPLEMENTARY GUIDANCE
ON CONDUCTING USE
ATTAINABILITY ANALYSES
ON EFFLUENT
DEPENDENT ECOSYSTEMS
Prepared fur.'
Water Quality Branch
EPA Region IX
llth Floor
75 Hawthorne Street
San Francisco, CA 94105
Prepared by!
Abt Associates
55 Wheeler Street
Cambridge, MA 02138
TetnTecb
3746 Meant Diablo Blvd.
Suite 300
Lafayette, CA 94549
March 1993
55 Wheeler Street Cambridge, Massachusetts 02138-1168 (617)492-7100 Fax: (617) 492-5219 TDD (617) 354-6618
-------
TABLE OF CONTENTS
CHAPTER ONE: INTRODUCTION AND
SUMMARY OF USE ATTAINABILITY ANALYSIS . . 1-1
1.1 Objective of Supplementary Guidance on Conducting UAAs of.
Effluent Dependent Ecosystems 1-1
1.2 Organization of the Supplementary Guidance 1-2
1.3 Background 1-2
1.4 Overview of UAA Process 1-4
1.4.1 Preliminary Evaluation to Determine if UAA is Appropriate 1-5
1.4.2 Evaluation of Factors Precluding Attainment of
Designated Uses 1-10
1.4.3 Limitations of UAAs 1-13
CHAPTER TWO: NET ECOLOGICAL BENEFIT COMPARISON 2-1
2.1 Introductioa 2-1
2.2 NEB Comparison Tasks . . 2-4
2.2.1 TASK 1: Define Ecological Benefits and Detriments 2-5
2.2.2 TASK 2: Construct a Succinct Description of the Waterbody .... 2-8
2.2.3 TASK 3: Develop Specific NEB Comparison Objectives
and Define Expected Performance . 2-13
2.2.4 TASK 4: Establish Testable Hypotheses and Select
Statistical Methods 2-18
2.2.5 TASK 5: Collect Data and Conduct Specified Analyses 2-23
2.2.6 TASK 6: Evaluate Net Ecological Benefit and
Determine Subsequent Actions 2-24
2.3 Arid City Treatment Plant: A Hypothetical Example 2-27
2.3.1 Description of the Receiving Waterbody 2-27
2.3.2 NEB Comparison Workgroup 2-29
2.3.3 NEB Comparison Workgroup Meetings 2-31
2.3.4 Results of State and EPA Review 2-37
2.4 Field Survey Sampling Design Considerations and Selected
Analytical Methods 2-38
2.4.1 Sampling Design Considerations 2-38
2.4.2 Statistical Design Considerations 2-40
2.4.3 Selected Analytical Methods 2-43
2.5 Design of Monitoring Program for Verification of
Net Ecological Benefit 2-57
2.5.1 Monitoring Program Design Tasks . 2-58
2.5.2 Data and Information Management 2-74
-------
CHAPTER THREE: DETERMINATION OF ECONOMIC AND SOCIAL IMPACTS OF
ATTAINMENT OF DESIGNATED USES 3-1
3.1 Introduction v 3-1
3.2 Evaluating Treatment Options That Would Allow the Discharger
to Meet Water Quality Standards 3-8
3.3 Measuring Financial Impacts 3-10
3.3.1 Measuring Financial Impacts To Private Entities 3-11
3.3.2 Measuring Financial Impacts To Public Entities 3-17
3.4 Measuring Socioeconomic Impacts 3-22
3.4.1 Measuring The Impact of Lost Water
Reclamation Projects 3-23
3.4.2 Measuring Socioeconomic Impacts on Private and
Public Entities 3-27
3.4.3 Measuring Socioeconomic Impacts As Applied To
More Than One Private And/Or Public Entity 3-32
3.5 Example Use Attainability Analysis based on
Economic Considerations 3-32
3.6 Summary Of Financial Capability And Determination Of
Whether Impacts Are Substantial And Widespread 3-44
APPENDIX A: INFORMATION ON THREATENED AND ENDANGERED SPECIES
APPENDK B: SPECIES LIST OF AQUATIC ORGANISMS
FOR ARIZONA'S EFFLUENT DOMINATED WATERS
APPENDIX C: POTENTIALLY INDIGENOUS ORGANISMS TO EPHEMERAL WATERS
11
-------
LIST OF TABLES
Table 2-1: Checklist of NEB Comparison Steps 2-3
Table 2-2: Example of Ecological Concern Statements 2-6
Table 2-3: Selected commonly measured physical and chemical parameters 2-14
Table 2-4: Selected Species Typical of Waterbodies in the Arid West 2-15
Table 2-5: Example of NEBC Objectives Derived from an Ecological
Concern Statement 2-17
Table 2-6: Example of Objectives and Hypotheses Supporting
a Selected Concern . . . 2-21
Table 2-7: References to Basic Statistical Tests 2-22
Table 2-8: Ecologies concern statements for the hypothetical example 2-32
Table 2-9: Example of NEB Comparison objectives derived from ah
ecological concern statement 2-33
Table 2-10: Example of Objectives and Hypotheses Supporting
a Selected Concern 2-35
Table 2-11: Biological Indices 2-47
Table 2-12: Example monitoring objectives 2-61
Table 2-13: Essential Elements of a Quality Assurance Project Plan 2-68
Table 3-1: Demonstration of Substantial and Widespread Economic
and Social Impacts of Attainment of Designated Uses 3-3
Table 3-2: Water Reclamation Project Example Cost Assumptions . . 3-26
Table 3-3: Data Submitted to the Arizona Department of Environmental
Quality by the City of Pleasantville, Arizona 3-34
m
-------
LIST OF FIGURES
Figure 2-1: Conceptual model showing top-down approach 2-10
Figure 2-2: Rudimentary conceptual model showing potential physical, chemical,
and biological features in the presence of the discharge
and in the absence of the discharge 2-11
Figure 2-3: Hypothesis testing: Possible Circumstances and Test Outcomes 2-19
Figure 2-4: Example box used to show distribution of data 2-63
Figure 2-5: Example distribution of mercury concentrations in fish tissue ...... 2-64
Figure 2-6: Example of preferred sampling locations near discharges 2-67
Figure 2-7: Example forms used for sampling 2-70
Figure 2-8: Selected example forms used in ODES/QA/QC process 2-71
IV
-------
CHAPTER ONE
INTRODUCTION AND
SUMMARY OF USE ATTAINABILITY ANALYSES
1.1 Objective of Supplementary Guidance on Conducting Use Attainability Analyses of
Effluent Dependent Ecosystems
This document is supplementary guidance to EPA Region IX's Guidance for Modifying
Water Quality Standards and Protecting Effluent-Dependent Ecosystems (1992), hereafter
referred to as Region DC's EDE Guidance. The purpose of this supplementary guidance is to
assist State/dischargers in their efforts to conduct Use Attainability Analyses (UAAs) on effluent-
dependent streams in the arid west. The Region IX EDE guidance covers other options for
modifying water quality standards in addition to UAAs including Total Maximum Daily Load
(TMDL) analyses and development of site specific criteria. Readers should be sure to consult
the Region IX EDE guidance in conjunction with this supplementary guidance.
This document outlines the major decision points for a Net Ecological Benefit UAA and
an economic UAA. It also describes the data needed to make decisions, and discusses methods
for obtaining the necessary water quality, biological, physical, and economic data. The intent
of the supplementary guidance is to help the State or discharger focus on the important data
needed to make a Net Ecological Benefit or economic UAA demonstration. Exhaustive
characterization of a system so that all possible factors may be analyzed is not necessarily
required for UAAs. Throughout this document, the term "State/discharger" refers to whomever
will actually conduct the UAA, whether it be the State, an individual discharger, a consultant,
or some other organization.
1-1
-------
1.2 Organization of the Supplementary Guidance
The majority of this supplementary guidance describes how UAAs based on Net
Ecological Benefit (NEB), or financial and socioeconomic impacts, should be conducted. As
discussed in EPA Region's IX EDE Guidance, these two factors are considered to be the most
likely approaches for UAAs in effluent-dependent streams. Chapter One provides background
on effluent-dependent waters, an overview of the UAA process, and a general discussion of data
needs for UAA demonstrations. Chapter Two describes how to perform an NEB Comparison
to demonstrate that a given discharge provides a Net Ecological Benefit. In addition, a
hypothetical example of such a demonstration in included. Guidance on designing monitoring
programs to verify that the newly modified uses/criteria are being met is also included in
Chapter Two. Chapter Three presents guidance on how a UAA based on financial and
socioeconomic impacts may be demonstrated and also includes a hypothetical example.
Particular attention is paid to the impact of pollution reduction costs on water reclamation
projects. The appendices include lists of threatened and endangered species in the Region DC
states: Arizona, California, Nevada, and New Mexico, references for threatened and endangered
species, and a list of species indigenous to ephemeral waters.
1.3 Background
In arid climates in the western United States, flow in streams is often low due to limited
recharge from grounctwater and infrequent storm events that occur only during certain times of
the year. In addition, streams may be partially diverted for drinking water supplies, industrial
uses, or irrigation. As a result, streamflow, particularly during the summertime, can be
dominated by discharges from human activities. Typically, such discharges may include:
wastewater effluent;
irrigation return flows;
reclaimed water discharges; and/or
urban runoff.
1-2
-------
Because streams may provide little or no dilution, water quality criteria often have to be met by
the discharge itself (i.e., at the end of the pipe). An important consideration in developing water
quality standards for these effluent-dependent waterbodies is that discharges may promote
restoration of habitat suitable for formally indigenous species. Effluent flows may enable
maintenance of certain forms of aquatic life, wildlife, and riparian or wetland habitat, even if
water quality criteria necessary to protect fishable/swimmable uses are not readily attainable.
Where water quality criteria are not met, State/dischargers may consider removal of the effluent
instead of additional treatment. If removal of the effluent would cause more environmental
damage than allowing it to continue, the discharger may be able to demonstrate that the effluent
is providing a Net Ecological Benefit. Examples of such benefits include the following:
provision or enhancement of habitat or food sources for native or
threatened/ endangered aquatic species, or migratory waterfowl;
provision or enhancement of habitat or food sources for terrestrial
native or threatened/endangered species;
enhancement or restoration of riparian values (e.g., increased species
diversity, growth of vegetation and improved wildlife/bird habitat);
preservation of existing riparian or aquatic habitat that could not be supported
without effluent flow;
restoration of aquatic and riparian values lost due to human activities
(prior to new effluent discharge);
enhancement of water quality resulting in conditions conducive to
ecosystem restoration and/or preservation;
improvement or creation of habitat capable of supporting fish or
allowing migration of anadramous species; and
restoration of species diversity in aquatic ecosystems.
There are restrictions, however, as to when a claim for provision of a Net Ecological
Benefit can be successfully made. These restrictions are discussed in Sections 1.4.1, 1.4.3 and
in Chapter 2.
1-3
-------
A separate consideration includes the cost of pollution reduction necessary to meet water
quality criteria in effluent-dependent waterbodies. These costs may. cause "substantial and
widespread economic and social impacts" to the community. Such costs may encourage
dischargers to remove or divert their wastewater from the waterbody. In addition, the cost of
pollution reduction may postpone or eliminate beneficial reclamation projects.
Where there are circumstances that would make meeting the water quality standards for
effluent-dependent waterbodies extremely difficult or impossible for either existing or proposed
discharges, State/dischargers may want to request a change or modification in the designated
uses of the waterbody. It should be noted that a designated use may only be modified if it is not
an existing use (40 CFR §131.12(a)(l)). An existing use (e.g. warm water habitat for aquatic
species) is defined as any use actually attained in the waterbody on or after November 28,1975
(40 CFR §131.3). In support of their request to change, remove, or subdivide uses, the
State/discharger will be required to conduct a Use Attainability Analysis (UAA). Briefly, a
UAA is a structured scientific assessment of the types of uses that have been, or can be,
potentially supported by a particular stream reach. The UAA may consider physical, chemical,
biological, and economic factors. ' '
1.4 Overview of UAA Process
The requirements of the UAA process are discussed in Section 131.10(g) of the Clean
Water Act. The UAA process involves four major steps. The first step is to determine if the
designated uses have been attained. If so, designated uses cannot be modified and a UAA is not
applicable. An alternative to a UAA that can be considered is to set site-specific criteria for
those uses. Guidance for setting such criteria is available from EPA in their Water Quality
Standards Handbook (U.S. EPA, 1982) and in EPA Region DCs Guidance for Modifying Water
Quality Standards and Protecting Effluent-Dependent Ecosystems. Other alternatives to the UAA
process are mentioned in Section 1.4.3. If designated uses have not been attained, the
discharger may be able to modify the designated uses by undertaking a UAA. The second step
of the UAA process is to confirm that all technology based requirements, as described in
sections 301 (b) and 306 of the Clean Water Act, have been met in a given waterbody (e.g.,
1-4
-------
existing point source treatment requirements have been implemented). The third step is to
identify factors that preclude or contribute to impairment of designated uses. Two approaches,
covered in this supplementary guidance document, are to undertake a Net Ecological Benefit
Comparison or to determine if compliance with water quality standards would result in
substantial and widespread economic and social impacts. The fourth step is to determine the
attainable uses of the waterbody and feasible treatment levels to meet the standards for those
uses.
If the UAA is approved, appropriate water quality criteria would be determined for the
newly designated use. These criteria would presumably be less stringent than for the original
designated use. This process can include setting site-specific criteria to meet the newly
designated use. If the UAA is not approved, the discharger or state still has the option of
determining site-specific criteria. Continuing consultation with EPA and state agencies
throughout the various steps of a UAA is recommended. Public participation in the UAA
process is required (40 CFR Part 25, 40 CFR Part 131, 20(a) and (c)).
1.4.1 Preliminary Evaluation to Determine if UAA is Appropriate
In conducting a UAA, the State/discharger is required to collect sufficient data to
demonstrate that certain preliminary criteria are met and that one or more of six allowable
factors precludes full attainment of a designated use. Remember, however, that water quality
cannot fall below that required to protect an existing use. The preliminary evaluation involves
a series of steps to answer the following questions:
1. Has the waterbody achieved its designated uses at any time since 1975?
2. Have existing point source treatment requirements been implemented?
3. Does the waterbody meet the criteria necessary to protect all existing uses?
4. If the waterbody does not meet the criteria necessary to protect existing
uses, what treatment options are there to reduce pollutants below present
water quality criteria?
1-5
-------
The first step pertains to whether designated uses have been attained in the waterbody at
any time since November 28, 1975. If so, designated uses cannot be altered. If a designated
use has not been attained, States may remove the use, or adopt subcategories of a use if it can
be demonstrated that the designated use cannot be attained due to any one of the six factors listed
in 40 CFR §131.10(g) (presented later in section 1.4.2). States may remove or modify a
designated use only if it is not an existing use and the modification will not adversely affect the
water quality of downstream waters or groundwater recharge. Designated uses are considered
attainable if, at a minimum, they can be achieved by implementing the effluent requirements of
Section 301 (b) and 306 of .the Clean Water Act (i.e., technology-based limits and cost-effective
and reasonable best management practices). If the water quality criteria for a designated use are
met based on these control technologies, the use is considered attainable, regardless of whether
that use actually occurs. If the use cannot be changed, the State/discharger has the option of
determining whether site-specific criteria should be considered. This option could prove helpful
in cases where a discharger wants to change their operation, or a new project, such as a water
reclamation project, is proposed for a waterbody where uses cannot be changed.
The second step addresses whether all point source treatment requirements have been
implemented. The discharger must comply with the technology-based limits before pursuing a
UAA (40 CFR Part 131.10). In addition, it is recommended that there be no other outstanding
regulatory or permit compliance issues for pollutants of concern in the UAA. It is also
recommended that applicable pretreatment and pollution prevention programs be in place for
pollutants of concern.
The third step considers whether the present water quality criteria for existing uses are
met or have been met at any time since 1975 (40 CFR §131.12(a)(l). The best water quality
and existing uses achieved since November 28, 1975 must be maintained. If water quality
sufficient to protect existing uses is not being attained, the final step requires the State/discharger
to identify all available treatment or pollution control/reduction options that would enable the
uses and associated criteria to be met. Such options could include source reduction, waste
minimization, recycling, pretreatment, or pollution prevention-based behavior. The remainder
of this chapter provides further discussion of these four steps.
1-6
-------
To make a successful demonstration of a UAA, the following information is needed:
stream designated uses and associated water quality criteria;
evidence of any use impairment;
water quality data between 1975 and present, or estimation of historical ambient
concentrations if data not available;
current point source treatment requirements;
influent and effluent data for existing discharge;
pollution control/treatment options for pollutants exceeding criteria; and
degree of compliance with other permit conditions.
Designated uses and present water quality standards for streams in the arid west can be
obtained from the following sources:
California Regional Water Quality Basin Flans and Inland Surface Waters Plan;
the Water Quality Assessment Document and standards regulations for Arizona,
(A.G. Rule #R92-Q06, Title 18, Chapter 11; Feb. 1992); and
the Nevada Standards for Water Quality (Chapter 445).
The extent of any impairment (e.g., fish kills, health advisories, dying vegetation) may
be noted in the basin plans or assessment documents. Information may also be obtained by
contacting federal/State Fish and Game departments, California Regional Water Quality Control
Boards, or state/county health departments. A "Fish Kill File" for information on kills that
occurred between 1960 and 1986 is included in the STORET database and can be accessed from
the National Computer Center. Recorded data include numbers of fish killed, geographic extent,
duration, species affected, cause of kill, land use in area near fish kill, pollutants present, and
source of pollutants. Information between 1987 and mid-1990 is available in hard copy format
from EPA's Assessment and Watershed Protection Division. The maintenance of the fish kill
1-7
-------
database was discontinued in mid-1990 (U.S. EPA, 1990). Other information may be available
in the State 305(b) reports. Section 305(b) of the Clean Water Act requires the States to provide
EPA with a report describing the water quality of all navigable waters within the State during
the preceding year. The 30S(b) reports may contain information appropriate for determining
both the nature and extent of impairment and for evaluating water quality since 1975.
If the waterbody of concern is included oh the 304(1) "short list", there may be pertinent
data in the background documents explaining why the waterbody is listed. Section 304(1) of the
Clean Water Act directs the States to provide EPA with a report that includes a list of waters
in which a designated use, after application of technology-based effluent limits, is not expected
to be achieved. Three lists of waterbodies have been generated:
"Long list" - State waters not meeting beneficial uses, regardless of reason.
"Short list" - State waters that do not meet either numeric or narrative
federal or State water quality standards for the toxic pollutants listed under
Section 307(a) of the Clean Water Act due primarily to point sources.
Summaries for each waterbody describe the water quality exceedances,
sources, and whether the beneficial uses of the waterbody have been
impaired.
"Mini list" - State waters that do not meet numeric water quality standards
adopted under Section 303(c) (2) (B) of the Clean Water Act for a priority
pollutant due to either point or nonpoint sources of pollution.
The water quality data for the waterbody of interest is used to determine if criteria set to
protect the designated uses have been met at any time since 1975. If so, these uses cannot be
changed. If not, the data should be reviewed to determine if standards are being exceeded and
by how much. For some waterbodies, a large water quality data set may be available, while for
others, there may be little or no existing data. Ideally, seasonal water quality data for the
pollutants of concern would be available at five year intervals between 1975 and the present.
At a minimum, two years of data from about 1975 and two years of recent data are
recommended. The data set should include conventional pollutants (e.g. dissolved oxygen,
biochemical oxygen demand (BOD), pH, ammonia, suspended solids), and ambient water and
sediment concentrations of metals and organic chemicals detected in the effluent or used by the
1-8
-------
discharger. The latter parameters will generally be more difficult to find. Potential sources of
data include federal, State and local government agencies, flood control districts, and local
colleges and universities. EPA water quality databases, including STORET and BIOS may be
helpful for obtaining ambient monitoring data. STORET contains conventional water quality
parameters, some priority pollutants, some biological parameters (e.g., fish and shellfish tissue
concentrations for metals and organic chemicals), and daily flow records from U.S. Geological
Survey (USGS) stream gauging stations. Software is available to compute statistical summaries
of the data and to prepare maps showing locations of the sampling stations. BIOS contains
information on distribution, abundance, and physical condition of aquatic organisms, as well as
descriptions of their habitats and information collected using the Rapid Bioassessment Protocols
(see Chapter 2). Summaries of the EPA's various automated data files are available in the
Office of Water Environmental and Program Information Systems Compendium (EPA, 1990 -
EPA,500/9-90-002).
Discharge data should be used to determine if technology-based treatment requirements
are being met. Influent and effluent flows and water quality may be obtained from the
discharger's own monitoring data, NPDES permit files located at EPA Regional offices or local
environmental agencies, the Permit Compliance System (PCS) database, or the Industrial
Facilities (DFD) database. The PCS database contains information on major facilities which
discharge to POTWs or surface waters. Data include facility location, NPDES permit number,
industry, permit limits, compliance schedule, and extent of any violations. The IFD database
includes information on industrial point sources to either POTWs or surface waters. Tabulated
data include facility name, location, NPDES permit number, industry type by standard industrial
code (SIC), flow rate, name of receiving water, and location of discharges. These files and
databases may include concentrations of conventional and toxic pollutants. Some information
may also be available from the Toxic Release Inventory (TRI) database. This latter database
includes releases to air and groundwater, in addition to surface water and includes information
similar to that in the IFD file. Because the TRI database is accessed by zip code, it is more
difficult to use than the IFD database. Treatment requirements and resolution of any other
permit compliance issues can be obtained from EPA and State agency files. Particular care
should be exercised to identify pretreatment requirements and any other types of pollution
1-9
-------
prevention programs (e.g., process changes, substitution of chemicals or materials used) that
have been requested by EPA or the State. Some information on these .activities may be available
from the PCS database.
If technology-based treatment requirements are not being met, the data should be used to
determine by how much the discharger is exceeding its NPDES effluent limits. For example,
the limit of a given substance is 5 ppb, but the effluent data show consistently that the effluent
quality averages 20 ppb, with a range of 15 to 40 ppb. This difference suggests that additional
treatment is necessary. By contrast, if the effluent data had been 6 ppb, this difference could
be due to a few high flow days and a major change in treatment levels is probably not necessary.
In this case, a small increase in residence time of the discharge in a settling basin might improve
the effluent quality enough to meet the criteria. Where necessary, appropriate treatment options
should be identified that would bring the discharge into compliance. At this point, all technically
viable options must be considered. The feasibility of the options from a cost standpoint is
addressed as a separate issue in the UAA process and is discussed in detail in Chapter Three.
1.4.2 Evaluation of Factors Precluding Attainment of Designated Uses
If a UAA is considered appropriate, the next step is to determine which factoids) will be
used to demonstrate why the use cannot be attained. The six possible factors (40 CFR
§131.10(g)) are listed below:
1. naturally occurring pollutant concentrations prevent the attainment of the use; or
2. natural, ephemeral, intermittent or low flow conditions prevent attainment of the use;
or
3. human caused conditions or sources of pollution prevent the attainment of the use and
cannot be remedied or would cause more environmental damage to correct than to
leave in place; or
4. dams, diversions, or other types of hydrologic modifications preclude the attainment
of the use, and it is not feasible to restore the waterbody to its original condition or
to operate the modification in a way that would result in attainment of the use; or
1-10
-------
5. physical conditions related to the natural features of the waterbody preclude
attainment of aquatic life protection uses; or
6. water quality-based pollution reductions more stringent than those required by Section
301 (b) of the Clean Water Act would result in substantial and widespread economic
and social impact.
EPA Region DC suggests that the State/discharger coordinate with EPA in determining
which factors are most pertinent to a given case. Because of the time required to collect the
necessary data, the State/discharger should begin development of a Work Plan and Management
Plan for a UAA as early as possible before expiration of existing discharge permits. Ongoing
coordination between EPA, the State, and the discharger will help complete the UAA process
in a timely manner. EPA will consult with U.S. Fish and Wildlife Service regarding the
modification of water quality standards and its effects on listed threatened or endangered species.
The objective of the UAA, therefore, is to demonstrate that a designated use cannot be
attained due to one of these factors. In the opinion of EPA Region IX, factor 3 (providing a Net
Ecological Benefit) and factor 6 (pollution reduction costs would result in substantial and
widespread economic and social impacts) would be the most likely factors to consider for most
effluent-dependent streams in the arid west. This supplementary guidance focuses only on these
two factors. A brief discussion of the four remaining factors is provided below.
The four remaining UAA factors each deal with some aspect of the physical or
chemical environment that may prevent attainment of a designated use. A UAA based on one
of these factors will need to: 1) identify the specific conditions preventing attainment of the use
and 2) demonstrate that those conditions are not related to the discharge. Factor one, naturally
occurring pollutant levels that prevent attainment of a designated use, may be appropriate to use
in areas where there are natural sources of pollutants (e.g., metals) within the drainage basin.
A stream where sulfur vents discharge sulfur and metals into the water is an example of
waterbodies where this factor might be applied. To conduct a UAA based on this factor, the
State/discharger will need to identify the location and mass loading from the natural sources
compared to the effluent loading and identify how the contaminant is preventing attainment of
1-11
-------
the use (e.g., acute or chronic toxic effects on species actually present in the waterbody) and
show that the natural sources cannot be controlled.
Certain water bodies in the arid west are likely to have limited designated uses due to
natural intermittent or low flow conditions (factor two). To demonstrate that these conditions
prevent attainment of a use, the State/discharger will need to describe long-term flow patterns
and identify the minimum flows required to maintain the designated use. For example, water
depths, even with the discharge, that are only a few inches deep may cause warmer temperatures
that limit the type of fish that the stream can support. Historic data on aquatic life uses in the
waterbody may be useful in demonstrating the role of ephemeral flows in preventing attainment
of use. Information should be obtained to determine the distribution of stream flows and stage-
flow relationships. Flow data can be obtained from USGS records, local flood control districts,
and in some cases, from the daily flow file in the STORET database.
The fourth factor allows the State/discharger to change designated uses when dams or
hydrologic modifications prevent their attainment. One example would be when fluctuations in
water depth caused by a dam release schedule prevent development of pools or cause the water
temperature regime to be too extreme for native fish species to survive. This situation,
however, does not always mean that a use cannot be attained. The State/discharger must also
investigate opportunities for restoring the waterbody to its original condition or for managing
the modifications in such a way that the designated use could be attained. For example, small
daily flows to maintain the minimum flow necessary to support fish could be released from the
dam. Scheduled releases during the summer months could be made to lower the water
temperature to acceptable levels and to keep riffle areas from drying up. Alternative
management strategies should be evaluated.
Finally, the fifth factor allows the State/discharger to change beneficial uses that cannot
be attained due to natural physical features of the waterbody. As it applies to aquatic life
beneficial uses, this would include characteristics such as a lack of suitable spawning substrate
or presence of physical barriers to fish migration. To conduct a UAA based on this factor, the
State/discharger will need to identify the specific needs of species normally present in the region
1-12
-------
that are not being met. A nonimpacted reach in a nearby stream should be compared to the
waterbody of concern to show the differences in characteristics when the species of interest, are
flourishing and when they are not.
1.4.3 Limitations of UAAs
One intent of the NEB UAA process, as interpreted in Region IX's guidance for effluent-
dependent waterbodies, is to help preserve or restore scarce aquatic or riparian habitat in arid
regions. EPA Region DC intends to restrict the use of UAAs, however, to discharges which do
not contain bioaccumulative or other pollutants which could harm wildlife or humans due to
bioconcentration in the food chain. This restriction would limit the types of organic chemicals
that could be discharged, as well as other substances such as mercury and selenium. In addition,
federal regulations on anti-degradation require that downstream water quality is protected.
k
If the requirements for changing or modifying uses in a waterbody cannot be met, the
State/discharger has two other options. The first is to set site-specific criteria that are protective
of the designated uses of the waterbody. Development of such criteria would consider species
actually present in the waterbody, as well as other physical and chemical factors that could
influence the behavior of metals, organics, or other pollutants. The second option is to conduct
a wasteload allocation for the waterbody of interest and to determine the total maximum daily
load (TMDL) that can be discharged and still allow the water quality standards to be met. This
option may be appropriate when waste loads from other nearby sources have decreased.
Additional information on wasteload allocations is presented in a recent document Guidance for
Water Quality Based Decisions: The TMDL Process, (U.S. EPA, April 1991).
1-13
-------
CHAPTER TWO
NET ECOLOGICAL BENEFIT COMPARISON
2.1 Introduction
One of the six factors that States may use to remove or adopt subcategories of a
designated use is to demonstrate that "human caused conditions or sources of pollution prevent
the attainment of the use and cannot be remedied or would cause more environmental damage
V
to correct than to leave in place" (40 CFR §131.10(g)). To modify designated uses using this
UAA factor, EPA Region DC has interpreted the demonstration to be that of showing that the
ecological benefits of permitting the discharge to continue exceed the ecological benefits of
removing the discharge from the waterbody. This chapter provides guidance on how to conduct
a Net Ecological Benefit (NEB) Comparison for an existing point source discharge to effluent-
dependent waterbodies in EPA Region IX's arid West.1 The reader should consider this
guidance to be supplementary to Region LX's (1992a) Guidance for Modifying Water Quality
Standards and Protecting Effluent-Dependent Ecosystems. Region EX recommends the use of
a total maximum daily load (TMDL) process rather than an NEB Comparison where modifying
designated uses for non-point sources. Specific topics addressed in this chapter include:
Essential NEB Comparison tasks;
A hypothetical case study illustrating the NEB Comparison process;
1 This technical document does not discuss the use of an NEB Comparison to demonstrate a Net Ecological
Benefit for new discharges. For a new discharge, data needed to complete an NEB Comparison will be derived
from predictive physical, chemical, and biological models rather than from field samples. Information on pertinent
watershed and surface water models is available by contacting the Center for Exposure Assessment Modeling
(CEAM) at the US EPA Research Laboratory in Athens, Georgia. CEAM also provides training courses and
technical assistance for the models it supports. A compendium of TMDL watershed models is also available (US
EPA 1992c). Results of sensitivity and uncertainty analyses will be required to assess model performance. Testable
hypotheses and the use of statistical analyses may also require modifications if deterministic models are used. To
demonstrate an ecological benefit for new discharges, special consideration should be given to the value of
preserving existing habitats and wildlife associated with naturally intermittent or ephemeral streams and whether the
effluent-dependent stream would be more desirable than the existing stream habitat (See US EPA Region DCs
(1992a) Guidance for Modifying Water Quality Standards and Protecting Effluent-Dependent Ecosystems for further
discussion of nonpoint sources and new discharges).
2-1
-------
Field survey sampling design considerations and selected analytical methods; and
Design considerations for a monitoring program verifying continued Net Ecological
Benefit.
A checklist outlining suggested steps (and associated information requirements) that a
State/discharger should complete to demonstrate Net Ecological Benefit is given in Table 2-1.
EPA Region IX expects the State/discharger to be able to demonstrate the following
conditions in order for a UAA based on Net Ecological Benefit to be approved:
The water body is in a primarily arid areas such that aquatic resources are limited
and ecologically valuable. The water body supports an ecologically desirable
aquatic, wetland, or riparian ecosystem and supports native plant and wildlife
species. For new discharges, the water body must have the potential to support
such ecosystems. '
Effluent discharges do not produce or contribute to concentrations of pollutants in
tissues of aquatic organisms or wildlife that are likely to be harmful to humans or
wildlife through food chain concentration.
The discharger documents that a feasible plan to remove the discharge is under
consideration.
The analysis demonstrates that a continued discharge to the water body has not
created and is not like to cause or contribute to violations of downstream water
quality standards or groundwater basins.
All practicable pollution prevention programs, such as pretreatment and source
reduction, are in operation. The discharger verifies that it has responded
appropriately to previous and on-going compliance actions.
In order to preserve the Net Ecological Benefits associates with the discharge, it
is recommended that the discharger commit to providing effluent to the stream that
is sufficient to protect and maintain the ecological benefit as determined by EPA,
and state and federal wildlife agencies (US EPA 1992a).
Region DC highly recommends that State/dischargers gain commitments to early and
continued participation and cooperation by local, state, and federal agencies, industry,
2-2
-------
Table 2-1
Checklist of NEB Comparison Steps
Steps
1. Demonstrate that US EPA Region K's
conditions for conducting an NEB are
met.
2. Identify regional and local ecological
concerns and develop list of ecological
benefits and detriments.
3. Develop succinct description of the
watershed of concern.
4. Develop specific objectives for the NEB
Comparison.
5. Establish testable hypotheses.
6. Identify data gaps and design a field
sampling program to obtain required
data, if needed.
7. Use existing and new data to evaluate net
ecological benefit and recommend
subsequent action.
8. If change in use approved due to NEB
Comparison, design monitoring program
for verification of NEB Comparison.
Information That Will Be Required
From Applicant
Brief report demonstrating that conditions
are met.
List of concerns and list of benefits. Obtain
EPA approval of list.
Narrative description or conceptual model of
key physical, chemical, and biological
components of the system.
List of specific NEB Comparison objectives
and performance criteria. Obtain EPA
approval of list.
List of testable hypotheses and methods for
assessment.
Sampling program workplan with
parameters, locations, sample collection/
analytical methods and QA/QC. Obtain
EPA approval of workplan.
NEB Comparison report and
recommendation for action. Obtain EPA
approval of action.
Monitoring program workplan.
Obtain EPA approval of workplan.
2-3
-------
environmental interest groups, and the academic community. Participation and consensus
reached by these parties throughout the NEB Comparison process fortifies the assessment and
ensures that few "surprises" will arise later. In particular, consultation with the U.S. Fish &
Wildlife Service is appropriate when modifying water quality standards. Whether a formal
process is needed to ensure participation by appropriate agencies, institutions, or organizations
can be decided on a case-by-case basis. Additionally, public participation in the UAA process
in the form of public hearings is required by law.
2.2 NEB Comparison Tasks
The six tasks that State/dischargers must complete to conduct an NEB Comparison are
as follows:
Task 1: Define ecological benefits and detriments;
Task 2: Construct a succinct description of the waterbody;
Task 3: Develop specific NEB Comparison objectives and define expected
performance;
Task 4: Establish testable hypotheses and select statistical methods;
Task 5: ColJect data and conduct specified analyses; and
Task 6: Evaluate Net Ecological Benefit and determine subsequent actions.
Completion of tasks 1 through 4 ensures that agreement on 1) definitions of ecological benefits,
2) specific NEB Comparison objectives, 3) what data are needed and 4) how the data will be
used to assess Net Ecological Benefit is established before any data are collected and analyzed.
Completion of all six tasks is necessary to conduct a consensus-based, cost- and time-effective
NEB Comparison. Because there are instances when unforeseen questions arise late in the NEB
Comparison process, iteration of these tasks may be necessary. Each task is described in detail
below.
2-4
-------
2.2.1 TASK 1: Define Ecological Benefits and Detriments
The State/discharger's most important task in conducting an NEB Comparison is to
identify and develop clear and succinct definitions of ecological benefits and detriments related
to continuing or removing the discharge. Benefits and detriments at all levels of the ecosystem
from the waterbody to the watershed should be considered. EPA encourages Net
Ecological Benefits that offer a comprehensive and coordinated approach to entire drainage
basins. In particular, special consideration is given to watersheds where various parties with a
stake in specific local situations are cooperating and where the ecological benefit is part of a full
range of methods and efforts for developing an integrated strategy for a geographic area. All
subsequent NEB Comparison efforts are directed toward quantifying or demonstrating that these
defined ecological benefits and detriments exist.
In developing succinct statements of ecological issues or concerns, the State/discharger
must define what they consider ecologically "beneficial" or "detrimental" (Table 2-2).
Ecological "benefits" and "detriments" associated with discharge, as well as valued resources,
are often implicitly defined in these concern statements. For example, ecological concern
Statement 1 implies that the presence of the discharge creates a benefit for the waterbody and
watershed by providing critical riparian habitat to an endangered species (Table 2-2). Concern
Statement 3 implies that the presence of the discharge is a "detriment" to the waterbody because
it threatens the existence of ephemeral flow adapted species. Decisions regarding what is an
ecological benefit or detriment, as well as how much of a benefit or detriment, must be defined
on a waterbody- or watershed-specific basis. For example, a major decision might be whether
the gain of perennial flow communities is a benefit compared to the loss of native intermittent
or ephemeral stream communities. In many cases, the bioaccumulation of contaminants into
valued resources is identified as a significant potential ecological detriment due to the presence
of the discharge.
Initially constructed ecological concern statements often reflect broad or general concerns.
Nonetheless, all general concern statements must be further refined to identify specific, predicted
2-5
-------
Table 2-2
Example of Ecological Concern Statements
Concern 1: The presence of the discharge results in the creation and
(Benefit) maintenance of riparian habitats critical to supporting a resident
endangered species.
Concern 2: The presence of the discharge results in the restoration of perennial
(Benefit) aquatic and/or riparian habitats to levels prior to water diversion
projects.
Concern 3: The presence of the discharge results in the loss of species adapted
(Detriment) to ephemeral, intermittent, or low flow conditions.
Concern 4: The presence of the discharge results in the increased degradation of
(Detriment) water and habitat quality resulting in risks to valued resources and
human health.
Concern 5: The discharger agrees to work with local authorities to restore and
(Benefit) enhance 20 acres of riparian habitats identified in an overall
enhancement plan for the watershed.
2-6
-------
beneficial or detrimental consequences to specific waterbody resources as a result of the
discharge. For example, the general concern that "removing the discharge may harm resident
endangered species" should be refined to State that "removing the discharge will result in the
loss of riparian habitats that are critical to supporting the resident endangered gila woodpecker."
Precise statements of ecological concerns provide specific definitions of ecological benefits and
are necessary prior to constructing a succinct, practical systematic description (Task 2) and
developing specific NEB Comparison objectives (Task 3).
Where appropriate, EPA encourages vegetation planting, restoration of channelorphology,
or other enhancement .efforts to provide an ecological benefit (Table 2-2: Concern 5). In.
describing the ecological benefit, the state/discharger should discuss the overall strategy for
creating, enhancing, managing, and preserving the habitat.
It is highly recommended that representatives of local, State, and federal agencies,
industry and environmental interest groups, and the academic community be invited to participate
in the development, prioritization, and approval of definitions of ecological benefits and
detriments. A workshop or workgroup meetings could be scheduled to define a manageable set
of ecological benefits and detriments. A set of "strawman" ecological concern statements has
been found useful in encouraging discussions among workshop/workgroup participants.
Strawman concern statements may be constructed from past and present local concerns, as well
as from concerns expressed at other areas within the ecoregion facing similar threats. In most
cases, it will not be feasible to assess all benefits and all detriments associated with the
discharge. Consensus on the most important ecological benefits and detriments attributable to
the discharge is critical and must be reached before subsequent NEB Comparison tasks can be
started.
2-7
-------
2.2.2 TASK 2: Construct a Succinct Description of the Waterbody
A fundamental understanding of waterbody resources, processes, and factors controlling
ecosystem interactions is required to conduct a practical NEB Comparison. Once definitions of
ecological benefits and detriments are established, the State/discharger should construct a
succinct description of the affected waterbody. The description should summarize the present
understanding of key physical, chemical, and biological components and processes related to the
concerns identified in Task 1. The purpose of the waterbody description is to assist in :
Determining how the discharge affects valued waterbody resources; and
Identifying the key underlying factor (or combination of factors) governing the
degree to which the discharge affects valued waterbody resources; and
Delineating what data are required to conduct the NEB Comparison.
The description should be succinct, addressing specific identified ecological benefits and
detriments; it should not be a generalized model of the ecosystem.
Conceptual models are recommended as effective vehicles for integrating, organizing, and
communicating our understanding and lack of understanding of physical, chemical, and
biological processes occurring in an effluent-dependent waterbody. By providing a common,
easy-to-understand language, conceptual models can also foster and focus discussions among
participants having different backgrounds and concerns towards developing specific NEB
Comparison objectives. Managers can use conceptual models to focus scientific discussions on
specific decision-making needs. Scientists can use models to describe the physical, chemical,
and biological information needed to support management decisions. Conceptual models may
also be used to identify information needs that must be filled before conducting NEB
Comparison analyses.
2-8
-------
Most of the information needed to construct the model can be taken from existing water
quality, sediment quality, and biological data. Additional data needs may be filled by consulting
9
local scientists, resource managers, and other experts. A top-down approach may be used to
organize the information into a conceptual model. A top-down approach divides complex
concepts into smaller elements that can be described in more detail. If these elements are
complex, each element can be further subdivided and described, and so on, until a model sub-
element presents a clear idea or tells a simple story (Figure 2-1). Figure 2-2 shows a
rudimentary conceptual model listing system attributes in the presence and absence of the
discharge.
Physical Attributes Defining system boundaries is the first step toward developing a
systematic description of the waterbody; boundaries delineate the scope of the system and serve
to focus NEB Comparison efforts. The geographic extent of the analysis depends upon
definitions of ecological benefits. If ecological benefits gained are at the watershed level, the
model must define the physical boundaries of the watershed; likewise, if ecological benefits
gained are at the waterbody level, physical boundaries of the waterbody must be defined.
In arid systems, two physical components often govern community structure and function:
Hydrology (e.g., water properties, distribution, and circulation); and
Substrate characteristics (e.g., sediment grain size).
Key properties (e.g., temperature, dissolved oxygen concentrations), amounts, timing, and flow
rates of available water are often principal determinants of aquatic, wetland, and riparian
community structure and function. A discharge may significantly increase the amount of aquatic
and wetland habitats in an area by adding constant water flow to the system (Figure 2-2)2 .
Likewise, the system's hydrology influences the distribution of dissolved and paniculate-
3As discussed earlier, special consideration should be given to the value of preserving existing habitats and
wildlife associated with naturally intermittent or ephemeral streams and whether the effluent-dependent stream would
be more desirable than the existing stream habitat.
2-9
-------
Figure 2-1
Conceptual model showing top-down approach. The component
"Contaminant Transformations" is described in more detail.
ro
i
CONTAMINANT
TRANSFORMATION
CONTAMINANT
TRANSPORT
Atmospheric
Deposition m
Water Column
Chemical Transformations
PtiytofXanklon zoopUnfcton Secondary Consumer Fishery Rnourc*
Biological Transformations
Consume! 17 n_
'.'.''."'-.'". ; Decomposers- ../'.' .'.'';'.'.'.' .'
..-'. Sediment '.. .
.'' r Chemical Transtormations -S
-------
Figure 2-2
Rudimentary conceptual model showing potential physical,
chemical, and biological features in the presence of the
discharge and in the absence of the discharge
System Descriptions
Presence of Discharge Absence of Discharge
Physical Features
Silt and day
Flow rates High, perennial
Dissolved Oxygen 6.2-18.0 mg/L
Chemical Features
Trace metals
Organics
Pesticides
Nutrients
Ammonia
Biological Features
Riparian vegetation:
willow
cottonwood
Wetland vegetation:
cattail
bulrush
Macroinvertebrates
Reptiles and Amphibians
Rsh:
Tilapia
Shiner
Birds:
Violet-crowned hummingbird
Yuma clapper rail
Physical Features
Sand and gravel
Row rates
Dissolved Oxygen
Chemical Features
Trace metals
Biological Features
Arid plants:
creosote bush
burrobush
Wetland vegetation
Rsh
Birds:
. Sage sparrow
Low, seasonal
6.2-8.0mg/L
None
None
7-1.1
-------
associated contaminants. In addition to providing information needed to assess habitat quality,
hydrologic information is often necessary to interpret other information (e.g., fate and transport
of contaminants).
Substrate characteristics are a second major physical factor influencing waterbody
community structure and function. Substrate composition, grain size, and organic content play
key roles in determining the vegetation types occurring in and around a waterbody.
Furthermore, sediment grain size, total organic carbon (TOC) content, and vegetation
composition strongly influence community complexity (e.g., types and numbers of organisms)
and productivity in an area. In addition, grain size and TOC are key determinants of
bioavailability for some contaminants in sediments. To assess the discharge's impact on local
aquatic and wetland habitats, a description of the system's substrate characteristics is highly
recommended.
Chemical Attributes A common ecological concern of discharges to effluent-dependent
waterbodies is the bioaccumulation of toxic contaminants in valued resources. NEB
Comparisons are not recommended for pollutants that bioaccumulate. Most waterbody
descriptions should provide available information regarding water and sediment chemistry within
the system. All known contaminant sources in the waterbody should be characterized, especially
contaminant loading from the discharge's effluent. Where available, contaminant concentrations
and distributions in the water column and in sediments should be described. Likewise,
parameters or processes affecting the rate and bioavailability of contaminants should also be
identified. For example, acid volatile sulfide concentrations in sediments have been found to
affect the bioavailability of some metals (US EPA 1991b; Appendix BIO : Bioaccumulation
monitoring).
Waterbody contaminant information frequently prove useful for identifying sources of
resource degradation and evaluating the attainability of beneficial uses. Measures of spatial and
temporal variability of water and sediment quality assist in characterizing the discharge's impact
2-12
-------
to key locations within the receiving waterbody. Table 2-3 includes a list of other commonly
measured physical factors.
Biological Attributes Net Ecological Benefit is often evaluated with respect to biological
resources (e.g., rare or endangered species, unique or special habitats). The State/discharger's
description of the waterbody's biotic structure and function should include valued assemblages
of plants and animals that are directly or indirectly affeasd by the discharge.
Rare, threatened or endangered species, candidate species, and native species occurring
in the waterbody should be identified. Relationships affecting animal community structure or
function should be described. Major plant associations found in and around the waterbody
should also be identified and their spatial distributions described. The important groups often
considered include : riparian, terrestrial, emergent aquatic, submerged aquatic, algae and
phytoplankton. Special attention should be given to riparian and wetland areas because these
plant communities support diverse and, sometimes, unique animal assemblages. Based on the
location and habitat requirements of valued animal species, States/dischargers should then
evaluate the suitability of habitats provided as a result of the discharge. Information on past
sightings of threatened/endangered species in California can be obtained from the Natural
Resources Diversity Database maintained by California Department of Fish and Game. Selected
plants and animals found in waterbodies in the arid West are in listed in Table 2-4. Contacts
and references on federal and State endangered species are listed in Appendix A. In addition,
information on threatened and endangered .species in California, Nevada, and Arizona is
presented in Appendix A.
»
2.2.3 TASK 3: Develop Specific NEB Comparison Objectives and Define Expected
Performance
Since it is not usually feasible to assess all benefits and all detriments associated with the
discharge, the State/discharger must select a reasonable set of ecological benefits and detriments.
Explicit and succinct NEB Comparison objectives define what benefits and detriments will be
2-13
-------
Table 2-3
Selected commonly measured physical and chemical parameters
'Physical . . -.'^iX'-.' ' ' ^;''-...' : -
Water column
temperature
depth
turbidity
current velocity
salinity
Sediments
grain size
Chemical :
"Water column
dissolved oxygen
nutrients
contaminants of concern
organics
metals
PH
Sediments
contaminants of concern
organics
metals
total organic caibon (TOC)
acid volatile sotfides (AVS)
oxygen demand (e.g., COD, BOD)
PH
2-14
-------
Table 2-4
Selected Species Typical of Waterbodies in the Arid West
Plant Sptcfc.
Anmnwed Coyole wDow Mriefe
CMUil. OwliMd Tiki
Ooodag ofllow
America coot Cacaao yiDoMhrai MiMMffi kki
America wigean Etfa«4 Momnffem
Bdud kac&her F«n*inoo. mny-owl PM-UM grebe
BkckaO Ofewndptckcr R«l-«a«ed bhcld
Bkck-faOicd »UKlic« duck OnMtfaeherao Rig-WW fuD
Bkct-cfaiaoeJ hunimich Lfcle eolonde tucker TbrwlliDdwl
Common cwp latAmtarti V«pn roondtul chub
bUUKUD flMOO Vo^lB CplDMKGB
Mc«CfioCih WomUin
MoMabi<|v«h|Mi *Y«qa chub
kMfar -Y«o> lopmmnow
YeOowhu.
Ytflowbunbad
Ore* phrin. «irw«)*haHc«d Umhod leootnl 6t«
ChlrioUMB MQptfQ tTQ£ HtBCDMOK tlfCT
Rcptfle Specie.
BoxMk
Brawn vac Mate Menon prtcmkc SoAibeO turtle
Mmml Specie.
Bamr ReJtal StcOed brt
Sbiped ikmk
- Fmli r.nj fanil Itrn^rn .1 m imhiti mil .|inrini
2-15
-------
assessed and how they will be assessed (Table 2-5). EPA recommends that, whenever possible,
quantifiable amounts of ecological benefits and detriments be specified by NEB Comparison
objectives. For example, if it is known that "x" acres of riparian habitat is needed to adequately
support a breeding gila woodpecker population, then the NEB Comparison objective should
specify "x" acres of riparian habitat (Table 2-5). All NEB Comparison objectives must be
addressed in Tasks 4 and 5 to ensure that selected, ecological benefits, detriments, and their
trade-offs are adequately appraised. Usually, the more benefits and detriments that must be
assessed, the more difficult it is to evaluate Net Ecological Benefit. It is therefore highly
recommended that a limited set of the most important benefits and detriments be selected. The
State/discharger should consult with EPA regarding the appropriateness of NEB Comparison
objectives. The quantity and quality of data needed to meet NEB Comparison objectives must
be agreed upon by regulating agencies prior to data collection and analyses.
NEB Comparison objectives are constructed from concern statements and knowledge of
the waterbody. States/dischargers must use these objectives to demonstrate that specific
relationships exist. For example, each of the three objectives listed in Table 2-5 must be
addressed before properly assessing Net Ecological Benefit (see hypothetical case study;
Section 2.3.1). Specific NEB Comparison objectives define what information is required and
how that information will be used to assess Net Ecological Benefit. They provide guidance for
the development of testable hypotheses (see Task 4) and subsequent data collection and analysis
efforts (see Task 5). Objectives must be established at the outset of the NEB Comparison
process before any data are collected.
Once objectives have been established, the State/discharger must develop NEB
Comparison performance criteria. These criteria set expectations for the levels of precision and
accuracy required to make sound decisions regarding net environmental benefit. Expected
performance criteria must define the levels of differences that must be detected by data analyses
(i.e., statistical tests) to demonstrate ecological benefit or detriment. For example, a
performance criteria may require that differences of 100% of the mean sediment copper
concentration must be detected by statistical tests to demonstrate that significant differences exist
2-16
-------
Table 2-5
Example of NEBC Objectives Derived from an Ecological Concern Statement
Concern 1: The presence of. the discharge results in the maintenance of riparian habitat
critical to supporting the resident endangered gila woodpecker.
NEBC Objective 1.1: Demonstrate that flows contributed by the discharge
result in the maintenance of cottonwood/willow
habitats downstream of the discharge.
NEBC Objective 1.2:
Demonstrate that the cottonwood/willow habitats,
maintained by discharge flows, provide critical habitat
to the endangered gila woodpecker.
Concern 4: The presence of the discharge results in the increased degradation of water
and habitat quality resulting in risks to valued resources and human health.
NEBC Objective 4.1:
Demonstrate that contaminant levels in these
cottonwood/willow habitats downstream of the
discharge are not a threat to the gila woodpecker and
other resident valued resources.
2-17
-------
between sites influenced by the discharge and reference sites. Data quality objectives (DQOs)
and the power to .detect relationships are important components in setting appropriate
performance criteria.
DQOs are specific, integrated goal statements developed by the State/discharger for each
information collection activity to ensure that the data are of the required quantity and quality to
meet their intended uses. DQOs should specify the desired sensitivity of sampling methods,
quality control/quality assurance (QA/QC) data needed to interpret other data (e.g., method
blank data), timing of sampling, and numbers of samples collected. For some evaluations of Net
Ecological Benefit, qualitative data may suffice. For example, the presence or absence of
specific organisms may be sufficient to demonstrate ecological benefits. For other evaluations,
quantitative data and demonstration of statistically significant relationships are required (see
Task 4).
The ability to detect significant relationships, or the power of statistical tests, is a critical
measure of NEB Comparison performance. The minimum power to detect relationships should
be defined by the State/discharger prior to performing analyses; actual test power should be
reported with all statistical test results. The choice of statistical probabilities (i.e., significance
levels (a) greater or less than 0.05; statistical power (1-/S) greater or less than 0.8) will depend
on the consequences of incorrectly rejecting a true null hypothesis or incorrectly accepting a
false null hypothesis, respectively (see Task 4; Figure 2-3).
2.2.4 TASK 4: Establish Testable Hypotheses and Select Statistical Methods
*
States/dischargers should establish testable hypotheses and select the statistical methods
that they will use to analyze the data prior to the collection of any data. These actions ensure
that sufficient and correct information is developed in the NEB Comparison. Testable
hypotheses specifically describe how data will be used to provide the necessary information to
support decisions of Net Ecological Benefit. To assess potential ecological benefits, NEB
Comparison hypotheses will often take the form of a null hypothesis (H,). A null hypothesis
2-18
-------
Figure 2-3
Hypothesis testing: Possible circumstances and test outcomes.
(where a = significance level; 1-P is statistical power)
O
CO
o
tu
o
ACCEPT
REJECT
HYPOTHESIS
ACTUALLY TRUE ACTUALLY FALSE
1-a
2-19
-------
usually states that there is no difference between sites affected by the discharge and the reference
sites as measured by specific physical, chemical, and/or biological metrics. If H. is rejected,
then the alternative hypothesis (H.) is accepted there is a difference between reference sites
and sites influenced by the discharge.
The progression from statements of ecological concerns to NEB Comparison objectives
' to testable hypotheses is demonstrated in the example shown in Table 2-6. This progression
ensures that data analyzed provide information to directly address specific NEB Comparison
objectives and ecological concerns. Comparing areas influence by the discharge to areas not
influenced by the discharge but ecologically similar in every other way (i.e., reference sites),
permits evaluation of whether the discharge creates an ecological benefit. For example, the
State/discharger demonstrates that there is a significant difference in the area! extent of
cottonwood/willow habitats found in areas influenced by the discharge than in those at selected
reference sites. This comparison provides the State/discharger with evidence that the discharge
results in the maintenance of the cottonwood/willow habitat.
The selection of appropriate statistical analyses depends upon null hypotheses, sampling
design, and distributions of the data. Statistical tests used to analyze the data must be specified
for each hypothesis. Results of the statistical hypothesis testing support whether or not to reject
constructed null hypotheses (Figure 2-3). A statistical test used to analyze data must be specified
for each hypothesis developed. Various statistical analyses are available depending on the form
and distribution of the data, and the question being asked (Sokal and Rohlf 1981). Selected
references that provide a discussion of basic analytical options available and background
information on the use of various statistical methods are summarized in the annotated k'st in
Table 2-7.
Plotting data is highly recommended as a first step in analyzing data. Parametric and
nonparametric analysis of variance (ANOVAs) in conjunction with ad hoc comparisons (e.g.,
Student-Newman-Keul's (SNK) test, Dunnett's test) may be used to detect differences among
several samples. Correlation and simple regression analyses may be used to measure the degree
2-20
-------
Table 2-6
Example of Objectives and Hypotheses Supporting a Selected Concern
Concern 1: The presence of the discharge results in the maintenance of critical riparian habitats
supporting the endangered gila woodpecker.
NEBC Objective l.J: Demonstrate that flows contributed by the discharge result in the maintenance of
cottonwood/willow habitats downstream of discharge.
NULL HYPOTHESIS 1.1.1: There is no significant difference in the area! extent of
cottonwood/wtttow habitats found in areas influenced by the discharge than in those at
selected reference sites.
NEBC Objective 1.2: Demonstrate that cottorrwood/wilJow habitats, maintained by the discharge,
provide critical habitat supporting the gila woodpecker.
NULL HYPOTHESIS 1.2.1: There is no significant difference in population abundances of gila
woodpeckers found in cottonwood/ willow habitats maintained by the discharge than in
habitats at selected reference sites.
Concern 4: The presence of the discharge results in the increased degradation of water and habitat
quality resulting in risks to valued resources and human health.
NEBC Objective 4.1: Demonstrate that contaminant levels in cottonwood/willow habitats
maintained by the discharge are not a threat to the gila woodpecker and other resident
organisms.
NULL HYPOTHESIS 4.1.1: There is no significant difference in sediment contaminant
concentrations in cottonwood/willow habitats maintained by the discharged than in reference
sites.
NULL HYPOTHESIS 4.1.2: There is no significant difference in water column contaminant
concentrations ta cottonwood/willow habitats maintained by the discharged than in reference
sites.
NULL HYPOTHESIS 4.1.3: Contaminant concentrations in the tissues of fish residing in
habitats maintained by the discharge pose no human health risks.
2-21
-------
Table 2-7
References to Basic Statistical Texts
Sampling Design
Sampling Design and Statistical Methods for
Environmental Biologists
(Green, 1979)
Introduction to principles and options for sampling
and statistical design. Examples of sampling design
and application of statistical methods.
General Statistics
Biometry
(Sokal and Roblf, 1981}
Biostatistical Analysis-
(Zar, 1974)
Applied Statistics, Principles and Examples
(Cox and Snell, 1981)
Basic reference to statistical techniques most
frequently used in the biological sciences.
Numerous examples of applications.
Basic reference to statistical techniques most
frequently used in the biological sciences.
Emphasis on analysis of variance techniques.
In depth examples of the most common statistical
applications.
Multivariate Statistics
Applied Multivariate Statistical Analyses
(Johnson and Wichern, 1982)
Applied Regression Analysis
(Draper and Smith, 1981)
Multivariate Statistical Methods: A Primer
(Manly, 1986)
Multivariate Statistical Analysis for Biologists
(Seal, 1964)
General introduction to multivariate methods.
Detailed introduction to regression techniques.
Includes section on planning large regression
studies.
Brief description of the most common multivariate
techniques, with examples.
General introduction to multivariate methods.
2-22
-------
of coincidence between two variables and to describe the dependence of one variable on another,
respectively. Trend analyses can be used to examine temporal and spatial patterns in the data.
Multivariate analyses are frequently used to reduce the dimensionality of complex data
sets to assist in identifying those key variables which describe the majority of the variability
observed in the data. Factor analyses and cluster analyses can be used to get a sense of what
physical and chemical processes may be important in "shaping" community structure and
function. Factor analyses and cluster analyses, however, can describe relationships where none
exists; factor analyses will find factors, cluster analyses will cluster. It is highly recommended
that these statistical analyses be used to explore and identify relationships that require further
investigation.
Power analyses are used to determine the ability of statistical analyses to reject null
hypotheses. The level of power required is defined by the NEB Comparison's performance
criteria. Power analyses provide a means to evaluate the efficacy of alternative sampling designs
if additional data are required. Further discussion and guidance for determining statistical power
can be found in Gilbert (1987), Sokal and Rohlf (1981), Green (1979), and Cohen (1977).
Active participation by local, State, and federal agencies is highly recommended. Review
of the methods should be conducted by agency technical experts, statisticians, members of the
scientific community, and other selected experts. It is recommended that review and approval
of the NEB Comparison analyses by appropriate regulating government agencies be sought to
ensure the acceptability of the NEB Comparison.
2.2.5 TASK 5: Collect Data and Conduct Specified Analyses
The use of existing data significantly decreases the cost of performing an NEB
Comparison. An evaluation of whether existing physical, chemical, and biological data are
2-23
-------
sufficient to adequately evaluate NEB Comparison hypotheses with the defined level of
performance should be conducted. The following questions should be asked:
Do data exist to evaluate identified hypotheses?
Is the quality of existing data sufficient to evaluate the NEB Comparison's
hypotheses?
Do existing data provide sufficient statistical power to evaluate the NEB
Comparison's hypotheses?
Data gaps may be filled by discussions with local experts or by conducting specific field studies
(see Section 2.4).
All analyses identified in Task 4 should be conducted to provide the needed information
necessary to evaluate Net Ecological Benefit. Interpretation of statistical tests and consequences
to the evaluation of Net Ecological Benefit should be discussed. Furthermore, the power of the
test to detect relationships should be reported with all statistical test results.
2.2.6 TASK 6: Evaluate Net Ecological Benefit and Determine Subsequent Actions
The evaluation of Net Ecological Benefit should be conducted based on information
provided by all NEB Comparison analyses. In some cases, an evaluation of Net Ecological
Benefit may be relatively straightforward. For example, if analyses indicate that 1) the
discharge is a significant contributor of water to the waterbody, 2) the water provided by the
discharge is critical to supporting local riparian habitats, and 3) these habitats are important to
the success of an endangered species, it can be strongly argued that the discharge provides a Net
Ecological Benefit. Some evaluations of Net Ecological Benefit, however, may not be as
straightforward. Tor example, habitats maintained by the discharge may also be sinks for
discharge contaminants. In addition, the habitat which supplies a haven for endangered riparian
2-24
-------
species may also pose a risk of contaminant biomagnification to these sensitive species.3 The
determination of Net Ecological Benefit, therefore, depends upon the degree to which each factor
poses a benefit or threat to valued resources. As previously noted, the more benefits and
detriments that must be assessed, the more difficult it is to evaluate Net Ecological Benefit. It
is highly recommended that a limited set of the most important benefits and detriments be
assessed.
During this phase of the NEB Comparison, discussions between the States/dischargers,
representatives of regulating government agencies, and scientists are essential in determining Net
Ecological Benefit. Peer review of the NEB Comparison evaluation by selected members of the
scientific community is strongly encouraged. The findings of the NEB Comparison should be
clearly reported; a discussion of the NEB Comparison's conclusion, how information was used
to reach the conclusion, and confidence in making the determination should be clearly presented.
As mentioned above, public participation and review of Net Ecological Benefits will also be
required.
The NEB Comparison will provide information to direct the State/discharger toward
subsequent actions. If a Net Ecological Benefit is demonstrated, the States/dischargers may
suggest that 1) a designated use be removed or 2) a subcategory of a designated use be adopted.
Results of the NEB Comparison may be used to identify subcategories of designated uses of a
water body or watershed that are attainable and to revise water quality criteria to protect the
modified uses.
It is then up to the State to revise the standards in the water body to reflect the uses that
are attainable. The discharger's NPDES permit may then be revised to reflect the new limits
associated with the revised criteria and the discharger may have to undertake some additional
controls to meet the revised effluent limits. The State/discharger should use the affordability
'Note that the reduced wastewater treatment levels would only be allowed if bioconcentration does not
pose a risk to the environment.
2-25
-------
criteria outlined in Chapter 3, Section 3.3 to determine what the next most protective pollution
reduction technique that the entity .could afford would be. Next, a monitoring program should
be implemented (see Section 2.5). Finally, as per federal regulations, the UAA must be
reviewed every three years to determine if there is any new information or technology that
allows attainment of the full designated use.
If a Net Ecological Benefit is not demonstrated, the States/dischargers may pursue any
of the following actions :
Develop new site-specific water quality criteria;
Examine other remaining 40 CFR §131.10(g) factors;
Propose creating a Net Ecological Benefit through enhancements to the waterbody;
Re-examine wasteload allocation and TMDLs;
Increase treatment of waste; or
Remove discharge.
Guidance for establishing new site-specific water quality criteria is provided in EPA's Water
Quality Standards Handbook (1983). Since most States/dischargers select the 40 CFR
§131.10(g) criteria which would give diem the best chance of demonstrating that the use cannot
be attained, examining other 40 CFR §131.10(g) criteria may not be a viable alternative solution.
Enhancements to the waterbody or watershed may be proposed by the State/discharger to
create a Net Ecological Benefit due to the presence of the discharge. For example, native seed
planting, wetland restoration projects, or channel modifications may be proposed as
enhancements leading to a Net Ecological Benefit. All proposed subsequent actions must be
discussed with representatives of EPA and other appropriate regulatory government agencies.
2-26
-------
2.3 Arid.City Treatment Plant: A Hypothetical Example
In this section, a hypothetical example is provided to highlight the process, types of
information, and analyses that are required to demonstrate a Net Ecological Benefit. Information
presented in this example is only illustrative and does not prescribe information requirements
for NEB Comparisons. In this example, the fictional city of Arid City, Nevada, is attempting
to demonstrate a Net Ecological Benefit in the Merton River.
2.3.1 Description of the Receiving Waterbody
Problem Description The effluent-dependent Merton River has several designated uses
including: (1) cold water aquatic life/spawning, (2) wildlife propagation, (3) water contact
recreation, and (4) non-contact recreation. Arid City operates a wastewater treatment plant that
discharges into the Merton River. The treatment plant's discharge has an average annual
ammonia concentration of 0.1 mg/L. The cold water aquatic life/spawning designated use is the
most restrictive of the aquatic uses for ammonia and has an un-ionized ammonia concentration
criteria of 0.02 mg/L.
The plant has already complied with secondary treatment requirements. After evaluating
the options of (1) further upgrading treatment to remove un-ionized ammonia from the discharge
and (2) removing the discharge, the Arid City Sanitation District has decided to remove the
discharge if forced to make the choice.
The discharger reviewed 305(b) reports and found that a cold water aquatic life/spawning
designated use has not been achieved in the river since 1975. Furthermore, the Arid City
Sanitation District and some local environmental groups have expressed concern that removal
of the discharge would result in the loss of critical habitat for the endangered violet-crowned
hummingbird (Amazilia violiceps) and that removing the discharge would cause more
environmental damage than it would to leave in place. In support of their contention, Arid City
is proposing to conduct a NEB Comparison that would support a modification in the designated
2-27
-------
use of the Merton River by changing the most restrictive designated use for ammonia (i.e., cold
water aquatic life/spawning) to a warm water adult aquatic life designation which has an un-
ionized ammonia concentration criteria of 0.3 mg/L.
Waterbody Description Surface flow in the Merton River is regulated by dams located on
the Merton River and its two main tributaries, Fish River and Bear Creek. During summer
months, flow in the river downstream of the dams is due entirely to effluent from Arid City's
secondary wastewater treatment plant (approximately 30 cfs). Arid City has a population of
approximately 100,000 and the area is experiencing rapid growth.
Areas Not Influenced by the Discharge Areas upstream of the wastewater outfall are
dominated by desert scrub vegetation, predominantly creosote bush (Larrea tridentata),
burrobush (Ambrosia dumosa), and shadescale (Atriplex confertifolia). Vegetation is extremely
sparse in this area and wildlife is limited. Seasonal flash floods have removed much of the finer
sediments and prevent the establishment of perennial vegetation in the riverbed itself.
Areas Influenced by the Discharge Below the Arid City outfall, a typical desert riparian
system exists. In 1980, local governments funded a restoration project on this portion of the
stream to eliminate stands of saltcedar (Tamarisk sp.) and establish Fremont cottonwood
(Populusfremontii) and willow (Salix spp.). Arrowweed (Pluchea sericea) is common along the
river's banks. In areas where receding floodwaters leave rich silt, dense stands of annuals such
as wild sunflower grow. Wildlife is abundant in this portion of the river, but most prominent
are the bird species utilizing the cottonwood/willow habitats for nesting and feeding. Seven
breeding species, including the endangered violet-crowned hummingbird, have been identified
in the area.
Invertebrate abundance in the vicinity of the outfall is dominated by midges of the genus
Chiromomus. Members of this genus are also found at areas downstream of the outfall, but
members of the midge genus Kheotanytarsus and the snail Physa are also abundant. Up to 1 km
2-28
-------
downstream of the outfall the ichtheofauna is dominated by introduced species including tilapia
(Tilapia sp.) and shiners (Natropis sp.). Further-downstream, fish densities are lower, but two
native species, the Sonora sucker (Catostomus latipinnis) and the longfin dace (Agosia
chrysogaster) have been found. Although the stream appears to provide suitable spawning
habitat for longfin dace, spawning of any fish has not been observed after November 1975.
Water temperatures during the summer months fluctuate diurnally between 17 and 25° C.
The pH typically ranges between 7.0 and 7.5, but has been measured as high as 8.5 during
summer. Dissolved oxygen levels remain above 6.0 mg/L throughout the year and have reached
18 mg/L during heavy plankton blooms. Arsenic, chromium, lead, and copper have consistently
been found in water samples, but at concentrations below State criteria. Two organic
compounds, ethylbenzene and bis(2-ethylhexyl) pbthalate have been detected in water samples.
Sediments are predominantly silty sand with some cobble in faster moving stretches.
They become anoxic at less than 2 cm from the surface up to 1 km downstream of the outfall.
The four trace elements found in water sairples, (,-rsenic, chromium, lead, and copper) as well
as mercury and nickel have been found in sediment samples. Neither of the organic
contaminants found in water samples have been found during sediment testing.
2.3.2 NEB Comparison Workgroup
Before undertaking an NEB Comparison, the Arid City Sanitation District consulted with
EPA Region DC and the Nevada Department of Environmental Protection. As described earlier
in this guidance, the discharger's responsibilities include :
Develop and gain EPA and State approval on definitions of ecological benefits and
detriments;
Provide a succinct description of the problem and the system;
Generate and gain EPA and State approval on NEB Comparison objectives and
performance criteria;
2-29
-------
Develop and gain EPA and State approval on candidate testable hypotheses and
statistical methods; r
Collect necessary data and conduct specified analyses; and
Evaluate Net Ecological Benefit.
The City assembled a workgroup to provide feedback to the sanitation district staff involved in.
preparing the NEB Comparison. The tasks for the workgroup were defined as follows :
Review definitions of ecological benefits and detriments associated with the
presence of the discharge;
Review specific NEB Comparison objectives and expected performance criteria;
Review testable hypotheses and selected statistical methods; and
Evaluate Net Ecological Benefit and recommend subsequent actions.
The workgroup provided a forum for agency involvement and peer review throughout the NEB
Comparison process. The workgroup consisted of representatives from regulating government
agencies, industry, environmental interest groups, and the academic community and had an
equitable blend of management and technical expertise. The workgroup was kept under IS
people to facilitate open and focussed discussions, and to ensure that NEB Comparison review
could proceed in a timely manner. All meeting agenda and materials were developed by the
discharger and sent to members at least 7 working days prior to the meeting.
In addition, two public hearings were scheduled one to announce the City's proposal
and approach for modifying the waterbody's designated use; the other to announce the findings
of the NEB Comparison and present subsequent actions.
2-30
-------
2.3.3 NEB Comparison Workgroup Meetings
Workgroup Meeting 1 The goal of the first workgroup meeting was to define specific
ecological benefits and detriments due to the presence of the discharge. In preparation for the
first meeting, the city's treatment plant staff provided workgroup members with a brief overview
of the NEB Comparison process (NEB Comparison Tasks 1-6), a set of strawman ecological
concern statements, and a succinct physical, chemical, and biological description of the receiving
waterbody. Existing information was collected that described the distribution and habitat
requirements of the violet-crowned hummingbird and other valued resources, distribution and
composition of riparian habitats, and nutrient and contaminant concentrations in the waterbody.
*
The workgroup revised and then used ecological concern statements to develop specific
definitions of ecological benefits and detriments. The benefit of particular importance was the
maintenance of cottonwood/willow habitats that supported the endangered violet-crowned
hummingbird (Concern 1; Table 2-8). The detriments of the discharge included increased
contaminant and nutrient loading to the receiving water body and loss of native species adapted
to intermittent or low flow conditions (Concerns 2 and 3; Table 2-8). The workgroup
concluded that if contaminant and nutrient concentrations found in cottonwood/willow and nearby
aquatic habitats posed a hazard to the violet-crowned hummingbird and other wildlife, any
benefits of the habitat would be negated. Definitions of ecological benefits and detriments were
sent to EPA Region IX and the Nevada Department of Environmental Protection for review and
final approval.
Workgroup Meeting 2 The purpose of the second workgroup meeting was to develop
specific NEB Comparison objectives and to define expected performance. The treatment plant's
staff generated a list of EPA-approved definitions of ecological benefits and detriments of the
discharge, and prepared a set of strawman NEB Comparison objectives and performance criteria
based on these benefits and detriments. Workgroup members used the strawman objectives to
develop a list of NEB Comparison objectives, each of which identified a specific endpoint to
assess ecological benefits and detriments (Table 2-9).
2-31
-------
Table 2-8
Ecological concern statements for the hypothetical example.
Concern 1: The presence of the discharge results in the creation and
maintenance of riparian habitats critical to supporting the resident
endangered violet-crowned hummingbird.
Concern 2: The presence of the discharge results in a significant loss of native
species adapted to ephemeral, intermittent or low flow conditions.
Concern 3: The presence of the discharge increases contaminant loadings to the
waterbody resulting in risks to valued resources of the waterbody.
2-32
-------
Table 2-9
Example of NEB Comparison objectives derived
from an ecological concern statement.
Concern 1: The presence of the discharge results in the maintenance of
riparian habitat critical to supporting the resident endangered violet-crowned
hummingbird.
NEBC objective 1: Demonstrate that flows contributed by the
discharge result in the maintenance of cottonwood/willow
habitats downstream of the discharge.
NEBC objective 2: Demonstrate that the cottonwood/willow
habitats, maintained by discharge flows, provide critical habitat
to the endangered violet-crowned hummingbird.
Concern 2: The presence of the discharge results in a significant loss of
native species adapted to ephemeral, intermittent or low flow conditions.
NEBC objective 3: Demonstrate that flows contributed by the
discharge result in an irreparable loss of native species adapted
to intermittent or low flow conditions.
Concern 3: The presence of the discharge increases contaminant loadings to
the waterbody resulting in risks to valued resources of the waterbody.
NEBC objective 4: Demonstrate that contaminant levels in
these cottonwood/willow habitats downstream of the discharge
are not a threat to the violet-crowned hummingbird and other
resident valued resources.
2-33
-------
Workgroup members agreed that strong qualitative information would be sufficient to
make some determinations of ecological benefits. For example, information on the
presence/absence of the discharge may be sufficient to demonstrate that treatment plant flows
maintain cottonwood/willow habitat. Workgroup members agreed, however, that it was
necessary to use quantitative water and sediment quality data, and appropriate field and
laboratory QA/QC data to adequately characterize exposure to contaminants and nutrients. All
agreed that measures of laboratory accuracy and precision, as well as statistical power must be
reported. Levels of statistical significance (a = 0.10) and power (1-0 = 0.8) for quantitative
analyses were established based on historical data and the professional judgement of workshop
members. NEB Comparison objectives and performance criteria were submitted to EPA Region
IX and the Nevada Department of Environmental Protection for review and approval.
Workgroup Meeting 3 The third workgroup meeting was held to review the discharger's
strawman null hypotheses and proposed statistical methods. Each NEB Comparison objective
had at least one testable hypothesis (Table 2-10). Planned parametric and non-parametric
statistical analyses were also presented by Arid City Sanitation District technical staff. For
example, a Kruskal-Wallis test, a non-parametric analysis of variance, was proposed to detect
differences in arsenic concentrations from water samples taken in aquatic sites adjacent to
cottonwood/willow habitats and reference sites (Null hypothesis 5; Table 2-10). A k-sample
test, a post-hoc non-parametric t-test, was to be used to determine which sites were significantly
different from each other. Workgroup members reviewed and approved the null hypotheses and
statistical methods submitted by the Sanitation District.
*
Workgroup Meeting 4 Findings of the Sanitation District's analyses were presented. The
complete absence of cottonwood/willow habitat upstream of the discharge and the presence of
7 continuous miles of cottonwood/willow habitat along downstream of the discharge indicated
that flows contributed by the wastewater discharge resulted in the maintenance of these riparian
habitats. Furthermore, the complete absence of the violet-crowned hummingbird upstream of
the discharge and the presence of 30 nesting hummingbirds in cottonwood/willow habitat
downstream of the discharge indicated that the riparian habitats maintained by the discharge
2-34
-------
Table 2-10
Example of Objectives and Hypotheses Supporting a Selected Concern
Concern 1: The presence of the discharge results in the maintenance of critical riparian habitats supporting
the endangered violet-crowned hummingbird.
NEBC Objective 1: Demonstrate that flows contributed by the discharge result in the maintenance of
cottonwood/willow habitats downstream of discharge.
Null Hypothesis 1: There is no significant difference in the areal extent of
cottonwood/willow habitats found in areas influenced by the discharge than in those at selected
reference sites.
NEBC Objective 2: Demonstrate that cottonwood/wiUow habitats, maintained by the discharge,
provide critical habitat supporting the violet-crowned hummingbird.
Null Hypothesis 2: There is *o significant difference in population abundances of
violet-crowned hummingbirds found in cottonwood/willow habitats maintained by the discharge
than in habitats at selected reference sites.
Null Hypothesis 3: There is no significant increase in population abundances of violet-
crowned hummingbirds found in cottonwood/willow habitats maintained by the discharge over the
last 4 years.
Concern 2: The presence of the discharge results in a significant loss of native species adapted to
ephemeral, intermittent or low flow conditions.
NEBC Objective 3: Demonstrate that flows contributed by the discharge result in an irreparable loss
of native species adapted to intermittent or low flow conditions.
Null Hypothesis 4: Populations of native species adapted to intermittent or low flow conditions
are absent within a 50 mile radius of the discharge.
Concern 3: The presence of the discharge increases contaminant loadings to the waterbody resulting in
risks to valued resources of the waterbody.
NEBC Objective 4: Demonstrate that contaminant and nutrient levels in cottonwood/willow habitats
maintained by the discharge are not a threat to the violet-crowned hummingbird and other resident
organisms.
Null Hypothesis 5: There is no significant difference in water column contaminant and nutrient
concentrations in cottonwood/willow habitats maintained by the discharge than in reference sites.
Null Hypothesis 6: There is no significant difference in sediment contaminant concentrations in
cottonwood/willow habitats maintained by the discharge than in reference sites.
2-35
-------
provided critical habitat supporting the endangered violet-crowned hummingbird. Bird surveys
indicate that the violet-crowned hummingbird population had increased by approximately 75
percent in each of the last three years.
Review of existing data indicated that native species adapted to intermittent and low flow
conditions were abundant upstream of the discharge. There appeared to be little threat of an
irreparable loss of these native species.
Insufficient data exists regarding contaminant and nutrient concentrations in the
cottonwood/willow habitats downstream of the discharge. A field study was therefore conducted
to provide the necessary information. Data collected for the treatment plant's effluent and at
aquatic sites proximal to the cottonwood/willow habitats included concentrations of metals and
selected organics (e.g., ethylbenzene and bis(2-ethylhexyl) phthalate), concentrations of ammonia
and other nutrients (e.g., total Kjeldahl nitrogen, total phosphorus), pH, temperature, and
suspended solids. Measurements of flow at the discharge, reference sites, and
cottonwood/willow habitats were also taken. The analyses indicate that insignificant differences
in dissolved contaminant and nutrient concentrations were found between reference sites and
aquatic sites bordering the cottonwood/willow habitat. Furthermore, measured contaminant
levels did not exceed State criteria. Elevated ammonia concentrations were transient and posed
no toxic threat to resident organisms. Historically, plankton blooms did not threaten resident
aquatic organisms and were not correlated with elevated ammonia concentrations.
Sediment contaminant analyses showed significant, though, slight differences in
contaminant concentrations between reference sites and aquatic sites bordering the
cottonwood/willow habitat. Bioassays of riparian sediments, however, showed no toxic effects
to sensitive experimental organisms. These results indicated that riparian and aquatic sediments
posed no threat to resident organisms. The workgroup recommended that monitoring at these
sites continue to ensure that these "no-threat" conditions persisted.
2-36
-------
Based on the information presented, members of the workgroup concluded that Arid
City's wastewater discharge provides a Net Ecological Benefit to the receiving waterbody. The
ecological benefit of the cottonwood/willow habitat and the animal assemblage it supports
outweighs identified potential ecological detriments due to the discharge. The workgroup
recommended that the discharger be permitted to modify the use of the Merton River and that
a monitoring program be established to :
Ensure that the modified designated use of the waterbody is attained; and
Verify that the identified Net Ecological Benefit is maintained.
The NEB Comparison report included the recommendations of the workgroup and was submitted
to EPA Region IX and the Nevada Department of Environmental Protection.
2.3.4 Results of State and EPA Review
Representatives of the Nevada Department of Environmental Protection (DEP) visited the
Merton River area and met with the Arid City Sanitation District staff and the workgroup. The
Nevada DEP subsequently approved the request for change in designated use, provided that
continued water and sediment sampling and bird surveys were implemented. The Nevada DEP
noted the desirability of involving various concerned groups in the UAA process and the
statistical analyses of sediment data for the cottonwood/willow habitat which showed that metals
and organic chemicals were not accumulating. The Nevada DEP forwarded the request to EPA
with the recommendation that it be accepted. The Region DC EPA administrator reviewed the
UAA report and accepted the recommendation after discussing the case with the state staff to
be certain that the discharge monitoring program would be implemented and overseen by the
state, and incorporated into the discharger's NPDES permit. They also suggested that aerial
photographs be taken to document the present extent of the habitat and at intervals in the future.
2-37
-------
2.4 Field Survey Sampling Design Considerations and Selected Analytical Methods
This section provides information about major aspects of the design and implementation
of NEB Comparison field studies. Field studies provide the data necessary to complete
hypothesis testing by filling identified data gaps. They are conducted only when existing
information is not adequate to assess Net Ecological Benefit. States/dischargers are encouraged
to use existing data wherever possible.
The design of a field sampling program begins with an assessment of existing information
about the waterbody of concern. Existing information is assessed by reviewing the available
data for "completeness" and "quality" and other factors that affect its use and comparability
(e.g., sampling methods) and comparing it with selected data quality objectives (DQOs). After
reviewing all available data, data gaps are identified by comparing the existing information with
the information needed to address specific testable hypotheses (see Section 2.2.4).
This section is divided into three parts, Sampling Design Considerations, Statistical Design
Considerations, and Analytical Methods. The first of these contains information pertaining to
the selection of reference sites, and setting DQOs. The second discusses general statistical
design considerations. The third section, Analytical Methods, outlines selected analytical
methods for measuring biological resources. These methods by no means represent an
exhaustive nor a prescribed list of the available survey methods; they are included to provide
examples of methods that might be useful when conducting NEB Comparison field survey. For
each method, sampling equipment, laboratory analytical techniques, and data use are discussed.
Each State/discharger will need to select appropriate methods and design a sampling program
based on the specific benefits to be evaluated.
2.4.1 Sampling Design Considerations
Reference Site Reference conditions provide a control for effects of the discharge on the
physical, chemical, and biological characteristics of the waterbody. As discussed in the previous
2-38
-------
chapter, the recommended approach in an NEB Comparison is to quantitatively compare
environmental conditions in areas affected by a discharge with conditions at sites removed from
the influence of the effluent (i.e., reference sites). To provide an effective control for effluent
effects, the reference site should be ecologically similar to the study site except it should lack
the influence of the discharge. The selection of an appropriate reference site is critical to an
accurate assessment of ecological benefit.
Reference sites may be either spatially or temporally removed from effects of the effluent.
Baseline data are temporally removed from the effects of the effluent in that they describe
conditions prior to addition of the discharge. It is highly recommended that baseline data be
used so long as the only condition in the waterbody that has changed is the presence of the
discharge. Such a comparison provides direct measures of environmental effects of the
discharge and thereby renders the most straightforward evaluation of ecological benefits. In
addition, the use of baseline data may significantly reduce costs by reducing the need for
additional sampling. If suitable baseline data are not available, near-field reference sites are the
next preferred type of control and then far-field sites.
Sites located upstream of the discharge in an area that is ecologically similar to the study
site in the absence of the discharge are also acceptable reference sites (near-field reference site).
These sites are spatially removed from discharge affects. However, if no suitable near-field
reference sites are available, the State/discharger may base the evaluation on comparisons with
a far-field reference site. Selection of an appropriate far-field reference site should consider
regional ecological characteristics and local land use patterns (U.S.EPA 1989) to ensure that
potential effects throughout the waterbody are properly evaluated.
Omernik (1987) identified 76 ecoregions in the conterminous United States. A map
delineating these regions can be found in U.S. EPA (1989). EPA recommends that the
State/discharger use a site within the same ecoregion when selecting a far-field reference site.
Considerations for selecting an appropriate reference site include physical characteristics, local
land use patterns that may affect water quality, and point and non-point sources of pollution.
2-39 .
-------
It is important that the selected reference site be as similar to study sites as possible with the
exception of influences due to the discharge. The Rapid Bioassessment Protocols (U.S. EPA
1989) provide guidelines for comparing the general physical characteristics of stream habitats
that may be useful in this evaluation.
Data Quality Objectives (DQOs) DQOs are specific, integrated statements and goals
developed for each data or information collection activity to ensure that the data are of suitable
quantity and quality. DQOs should specify the desired sensitivity of sampling methods, time of
sampling, and number of samples to be collected for each variable being measured. DQOs are
used to delineate QA/QC programs specifically geared to the data collection activities to be
undertaken. Development of DQOs usually consists of three processes: 1) decision definition,
2) data use and needs identification, and 3) data collection program design. DQOs must be
developed based on the quality of data needed to assess NEB objectives. NEB objectives,
expected performance, and testable hypotheses statements must be used to develop appropriate
DQOs. DQOs may be reviewed during data collection activities and any needed corrective
action may be planned and executed to minimize data quality problems before they become
.significant.
DQOs play an important role in the selection of sample collection, sorting, and analysis
methods. In fact, sampling program design should be driven by DQOs. Any future
modifications to sampling protocols should be considered only after these new methods are
demonstrated to meet established data performance criteria. Data collected with different
methods should not be compared unless information exists which supports such comparisons.
2.4.2 Statistical Design Considerations
Prior to collecting any data, the State/discharger must determine how the data will be used
to support decisions. It is recommended that analytical performance criteria (e.g., minimally
acceptable Type I and Type n error) be defined to establish quantitative expectations for the field
study. The link between data, performance and decision-making should be specified a priori
2-40
-------
to ensure that appropriate data, and spatial and temporal coverage are addressed by the
monitoring plan.
As a general recommendation, equal numbers of replicate samples should be collected
whenever possible to simplify statistical analyses. Determining the appropriate number of
replicates to meet selected performance criteria is an important component of program design.
The number of replicates collected will determine whether the data is able to meet program
objectives and will greatly influence program costs. Power analyses can be used to examine
alternative sampling and compositing strategies and develop a more effective monitoring design.
These statistical techniques may prevent unnecessary sampling and thereby reduce the costs of
collecting and processing samples. Composite sampling (combining field samples collected for
chemical analyses) is another means of minimizing costs while ensuring that adequate data are
collected. Composite sampling reduces the number of samples for laboratory analysis and
thereby reduces costs. Statistical power and composite sampling are described more fully below.
Statistical Power Statistical power is a measure of the ability to detect real differences in a
variable statistically. Power analyses allow the statistical implications of alternative sampling
designs to be evaluated. They can also be used to assess the possibility that the absence of a
significant ANOVA result is caused by inadequate sampling design. Power analyses may be
applied to determine the appropriate number of sample replicates, and/or subsamples in a
replicate composite (see Composite Sampling, below), required to detect a specified difference
(U.S. EPA 1991). The number of replications required to detect a specified minimum difference
is a function of the statistical power and the variance in the data. Power analyses require a prior
knowledge of the variability in the data. A best guess of variation based on historical data is
often used initially in the design of the monitoring program.
The large degree of temporal and spatial variability observed for many ecosystem State
and rate variables requires collection of sufficient replicate samples to ensure an accurate
description of the measure of interest. Increases in replication, however, increase sample
2-41
-------
processing costs. Power analyses assist in the allocation of sampling resources (stations,
replication, and frequency) with regard to program finances and .design (Sokal and Rohlf 1981).
To improve the power of a statistical test, while keeping the significance level constant,
sample size can be increased. However, due to constraints in cost and time imposed this option
will not always be reasonable. Power analyses have shown that for a fixed level of sampling
effort, collecting more replicates at fewer locations is a more cost-effective means of meeting
program goals. The number and distribution of sampling locations required to meet study
objectives will depend upon, the size and complexity of the system.
Composite Sampling Composite sampling consists of mixing two or more replicates from
a single location. Collecting samples from two or more locations and compositing them is
termed space-bulking. Collecting multiple samples over time at a single location and
compositing them is termed time-bulking. The chemical analysis of a composite sample provides
an estimate of the average contaminant concentration for the locations and/or times comprising
the composite sample. . .
Composite sampling is advantageous because it provides a cost-effective method for
estimating mean chemical concentrations by reducing the number of individual chemical analyses
required. If chemical concentrations are highly variable, compositing can be used to reduce
sample variance. This reduction in sample variance will also increase statistical power. For
composite samples, statistical power increases as the number of subsamples in each replicate
composite sample increases (U.S. EPA 1991). There are diminishing returns of statistical
power, however, with the addition of successive subsamples beyond a certain number. Given
typical levels of data variability, there is a negligible increase in power beyond ten replications.
A disadvantage of using space- and/or time-bulking strategies is that significant
information concerning spatial and temporal heterogeneity may be lost. If the primary objective
of a sampling program, however, is to determine differences in contaminant concentrations
among locations, composite sampling is an appropriate strategy.
2-42
-------
2.4.3 Selected Analytical Methods
This section identifies and describes sampling and analytical methods that are used in field
sampling programs. The primary purpose of this section is to provide the State/discharger with
a basic understanding of the sampling methods that can be used in the NEB Comparison. In
addition, information is provided highlighting the feasibility and the use of field study results.
The methods and recommendations described in this section can be used to guide decisions
regarding the selection of individual techniques as well as appropriate quality assurance and
quality control procedures.
As stated in Section 2.1, standardized sampling and analytical protocols and a
performance based quality assurance program should be developed for each sampling program.
This strategy will ensure comparability of data. The most important component of a well
designed sampling program, however, is a competent, knowledgeable staff that will conduct
sampling and sample and data analysis. This document is designed only to provide general
guidance for designing a sampling program suitable to fill identified data gaps. As such, it
cannot anticipate the informational needs of each NEB Comparison. This information can only
be provided by technical personnel who are knowledgeable of sampling and analytical techniques
as applied to the region of concern.
Biological Resources: Infauna, Fish, and Birds An analysis of biological communities is
frequently used to assess impacts and detect aquatic life impairments (U.S. EPA 1989). For the
purposes of an NEB Comparison, sampling may include populations or communities of fish,
benthic invertebrates, and/or birds among others. Community analysis is useful because
biological communities reflect the integrated impact of different stresses and can readily be
interpreted as an indicator of environmental condition. It is reasonable that ecological benefits
be evaluated with respect to some biological endpoint represented by a measure of community
structure or function. Ecological benefits will frequently be related to the occurrence of a
certain species or group of species. In the Merton River hypothetical example, the violet-
crowned hummingbird (Amazilia violiceps) might be such a species. The appropriate biological
2-43
-------
endpoints for assessing ecological benefits will depend on the hypotheses and performance
criteria selected.
In this section, major considerations in the approach to evaluating populations or
communities of three animal groups typically occurring in riparian and wetland habitats (benthic
infauna, fish, and birds) are described. These methods can be used to obtain information about
populations of individual species or the overall structure and function of communities. However,
this section is not intended to represent a compendium of methods, but rather an initial guide
for developing a general .study plan. Depending on the specific NEB Comparison objectives,
measures of biological communities alone may be suitable indicators of ecological benefit or they
may need to be evaluated relative to certain aspects of the physical environment. The suitability
of these measures and the need for ancillary data should be determined through consultation with
EPA Region DC and other concerned agencies before field sampling is begun.
Sampling equipment The wide variety of devices that can be used to collect benthic infaunal
invertebrates can be divided into two general categories; grab samplers and box corers (Mclntyre
et al. 1984). Each device samples the benthos in a unique manner and conducting comparisons
among data collected using different devices is not advisable. It is recommended that the same
area and volume of sediment be sampled since different species of benthic macroinvertebrates
exhibit different horizontal and vertical distributions (Elliot 1971). If sedimentary conditions are
to be measured, the collection of sediments and benthic organisms should be done concurrently
to minimize field sampling costs and to permit sound correlation between these variables and the
use of multivariate analyses.
Fish samples can be collected using traps and cages, passive nets, electrofishing, or
photographic techniques (Fredette et al. 1989). Many of these devices selectively sample
specific types of fish. Accordingly, conducting comparisons among data collected using
different devices is not appropriate.
2-44
-------
Traps and cages are usually designed to attract and capture specific species. They are
useful in studies examining the activities of a particular target organism in a given area. Traps
and cages, however, provide only a qualitative measures of organisms in a particular area.
Traps or cages can be used to demonstrate the presence of certain species in an area, but cannot
provide quantitative information to evaluate distribution and abundance.
Passive nets (e.g., gill nets) are deployed at a fixed position and individuals become
entanried or trapped within the netted area. They are highly selective in the species captured
and in the efficiency of retaining captured specimens. For this reason, passive nets can be used
to collect a selected species of concern. However, specimens are frequently killed during
collection. If the species of concern is a threatened or endangered species, gill nets should not
be used. Limitations associated with passive nets include:
Specimens can be killed during collection if careful monitoring of the net is not
maintained;
Use of nets provide qualitative data only;
Nets, ordinarily, must remain in-place for an extended period of time; and
Deployment and recovery of nets is typically a time-consuming process.
The size of the net, its configuration and orientation, and possible avoidance behavior of the
target species should be considered when using any net.
Backpack electroshockers are the preferred equipment for electroshocking on small
streams. One person operates the electroshocker and is typically assisted by one or more
persons using dip nets to capture the stunned fish. All crew members must wear rubber gloves
and waders while sampling.
Photographic surveys are effective when the bottom topography is uneven or a
nondestructive sampling method is required. The utility of photographic surveys, however, is
2-45
-------
limited by water clarity, difficulties identifying species, and fish avoidance of the camera system.
This method is also limited by the qualitative nature of the data.
Censusing bird species requires experienced personnel capable of identifying species by
sight or, particularly in breeding surveys, by call. Censusing will usually be done at point sites
or along transects. Mist nets can be used to capture birds for marking and measurement of
physical characteristics and condition. By standardizing the placement and sampling period
when using mist nets, the relative abundance of a species can also be evaluated. Mark and
recapture of individuals allows the specific uses of different habitats to be evaluated.
Analytical techniques There are a number of widely accepted measures of community
structure and function that can be applied to different groups of organisms (e.g., fish, benthic
invertebrates). The use of these measures in assessing environmental conditions is based on the
predictable responses of individuals, species or groups of species to environmental stress.
Several of the more frequently used measures of community structure and function are listed in
Table 2-11. The most informative measures are frequently the simplest, including: number of
individuals, number of species, and the occurrence of indicator species (e.g., pollution tolerant
or pollution sensitive species). More complicated measures have found varying degrees of
acceptance. For example, Green (1979) found that the index of diversity often lacked biological
meaning, did not incorporate information about the form and function of resident species, and
was susceptible to biases associated with well described taxa.
, Simple measures of community structure and function have proved to be useful for various
habitats and regions in assessing differences in communities (U.S. EPA 1991b). Values for
these metrics are easily generated from a list of species abundances collected during field
surveys. Furthermore, the significance of differences among these variables may be tested
statistically using parametric or nonparametric techniques. It is recommended, however, that
no single measure be used to assess environmental condition; rather, the assessment should
incorporate information that each variable contributes concerning community structure. It is also
important to understand the ecological significance of a measure no matter what metric is used
2-46
-------
Table 2-11
Biological Indices
Index/Method
No. individuals
No. species
Opportunistic and pollution tolerant species
Pollution-sensitive species,
Biomass
Margalef s SR
Pielou's J
Shannon- Weiner H
Recommended
Biological for Measurement
Characteristic Method of:
Total abundance P,B,F,A
Total taxa P.B.F.A
Community structure P.B
Community structure P,B
Standing crop P.B.F
Diversity P,B,F,A
Evenness P,B,F,Ak
Diversity P,B,F,Ak
, P (plankton), B (benthos), F (fishes), and A (birds) indicate those biological gropus to which a
given index may be applied.
fc May be used together as additional indices of community structure.
2-47
-------
in assessing environmental condition. The use of indicator species is directly linked to the idea
of ecological significance in the assessment of environmental condition. The term indicator
species is commonly used to group species based on their relative tolerance (or intolerance) of
pollution. For the purposes of a NEB Comparison it may be appropriate to use species that are
commonly associated with a desirable habitat type as indicator species. The occurrence of such
species in an area could be used to demonstrate the existence of such habitats. Wetlands, for
example, are frequently identified by the occurrence of plant species common to these habitats
(Federal Interagency Committee for Wetland Delineation 1989).
Evaluating the structure of benthic infaunal communities is a widely-accepted means of
measuring the condition of benthic habitats (Bilyard 1987). Benthic infaunal organisms are
exceptional indicators of benthic conditions since:
They are generally sedentary - observed effects are in response to local
environmental conditions;
They are sensitive to habitat disturbance - communities undergo dramatic changes
in species composition and abundance in response to environmental perturbations;
and
They often mediate the transfer of nutrients and toxic substances in the ecosystem
- via bioturbation and as important prey organisms.
The assessment of benthic infaunal or fish community structure is a powerful tool in the
evaluation of spatial and temporal effects of anthropogenic and natural disturbances. In an NEB
Comparison, such measures can be used to evaluate the condition of aquatic habitats at areas in
the vicinity of a discharge relative to conditions at a reference site (see for example U.S. EPA
1989). Also, changes in the benthic community along a gradient of decreasing effect of the
discharge (increasing distance from the outfall) can be used to evaluate the spatial extent of its
influence.
Electrofishing is a popular method for estimating species composition and abundance of
fish communities (Calliet et al. 1986). Price (1982) describes a method for quantitatively
2-48
-------
sampling small streams by sectioning off a stream using vertical nets to prevent fish movement
into or out of an area. In an NEB Comparison, this method could be used to estimate species
abundance and to capture individuals for describing life history characteristics or evaluating the
physical condition of individuals. Species vary in their susceptibility to this method, however,
such that some species (e.g., suckers) are easily influenced, while others (e.g., freshwater
perches) are not (Calliet et al. 1986). Also, certain benthic species, although readily
incapacitated by the electrical current, may lodge beneath rocks and remain undetected.
Avian communities are strongly influenced by the condition and extent of riparian habitats
in the arid southwest (Meents et al 1984). Because this group also has a high public value, the
provision of habitat suitable for certain bird communities will often be viewed as an ecological
benefit. The relative abundance of birds can be estimated based on counts of sound and/or
visual cues along established transects or from set points. Recommended techniques for
conducting breeding bird censuses are provided in Svensson (1970) and Van Velzen (1972) and
for wintering bird populations in Kolb (1965). Anderson et al. (1977) outline a technique for
conducting studies to assess the effects of certain habitat variables (e.g., vegetation density and
structure) on avian community structure. This type of study can also assist the State/discharge
in developing a management plan for habitats provided by an effluent-dependent waterbody that
can further increase ecological benefits.
Sample collection protocols influence all subsequent laboratory and data analysis; it is
critical that no matter what species are being evaluated, samples be collected using acceptable'
and standardized techniques. Specific protocols for conducting all biological sampling should
be developed before field sampling is begun. Standardized procedures, designed explicitly for
conducting biological assessments, have been developed by various Federal and State agencies
(U.S. EPA 1989). The use of such protocols will: 1) standardize sampling and analysis
methods, 2) provide comparable data from different sources, and 3) increase cost-effectiveness
of biological assessment programs. In the long-run, the application of standard protocols in
conducting biological assessments will greatly increase the value of accumulated databases.
2-49
-------
Standardized methods will also facilitate comparisons with established reference sites and can
thus reduce sampling requirements.
Rapid Bioassessment Protocols EPA, in conjunction with a number of State agencies, has
developed five biological assessment protocols (U.S. EPA 1989) that may be particularly useful
in providing information for an NEB Comparison. These protocols, referred to as the Rapid
Bioassessment Protocols, are applicable to streams and rivers throughout the United States.
Three of the protocols are based on measurements of benthic macroinvertebrate community
structure and function. Two are based on fish community structure and function. Each protocol
uses measurements of the physicochemical and habitat characteristics of a site to interpret results
of the biological surveys and define appropriate reference conditions.
Rapid Bioassessment Protocols I and IV, are intended to be screening tools for the
assessment of benthic macroinvertebrate and fish communities, respectively. These protocols
provide qualitative data only and will not be suitable for the analyses generally required when
conducting an NEB Comparison. The remaining protocols could be applied in an evaluation of
the relative condition of macroinvertebrate or fish communities. Before applying these protocols
to an NEB Comparison, however, the State/discharger should consider: 1) the suitability of
macroinvertebrate and\or fish community condition for evaluating objectives, 2) the availability
of data from a suitable reference site, and 3) the ability of Rapid Bioassessment Protocols to
meet performance criteria.
If applicable to the hypotheses being tested, these techniques will provide the
State/discharger with standardized methodologies to use in field surveys. Using Rapid
Bioassessment Protocols in an NEB Comparison increases the opportunity for the
State/discharger to use existing reference data. As stated in the discussion of reference sites
(Section 2.4.1), the basis of an NEB Comparison often centers around comparisons of conditions
in areas influenced by the discharge with conditions at a reference site. Because biosurveys
based on Rapid Bioassessment Protocols can be evaluated for comparability of data (due to the
physicochemical and habitat assessments), the opportunity to use existing data to describe
2-50
-------
reference conditions is greatly enhanced. Furthermore, U.S. EPA has developed a biological
data management system (BIOS) suitable for the storage and analysis of Rapid Bioassessment
Protocol data. This database could provide the State/discharger access to existing regional
reference data. If such data were available it could significantly reduce the cost of field surveys.
The major limitation in applying Rapid Bioassessment Protocols in a NEB Comparison
is the restriction to macroinvertebrate and/or fish community assessments. Although one of
these communities will frequently provide valuable insights as to overall environmental
conditions, their suitability in any given situation will depend largely on the identified issues.
For example, if the majority of identified issues are related to the affect of the discharge on
wetland or riparian habitats, an assessment of macroinvertebrate or fish community conditions
will provide little relevant information. Another possible disadvantage to these protocols is that
the most rigorous Rapid Bioassessment Protocols (RBP m and V) provide rankings of the
relative condition of water bodies based on the values of several metrics; they do not incorporate
the use of statistical tests. If statistical tests are required to meet performance criteria, Rapid
Bioassessment Protocols will not be suitable for analyses.
Data use The objective of evaluating the structure and function of biological communities is
to detect and describe spatial and temporal changes of the community. Results can be used to
assess the condition of aquatic habitats and thus evaluate potential ecological benefits. Benthic
infauna and/or fish community structure, for example, provide in situ measures of the condition
of aquatic habitats. The occurrence of certain species or groups of species (e.g., the relative
proportion of native vs. introduced fish species) is a useful indicator of ecological condition.
The time of the year should be controlled or stratified in the sampling design; the use of
annual averages is seldom good practice, especially for species which are seasonally variable.
Temporal stratification of the data should not be attempted until sufficient knowledge of long-
term natural cycles is attained. Initially, simple regression analyses may be conducted on
seasonally stratified data in order to identify monotonic temporal trends. Further examinations
2-51
-------
of whether conditions are improving or degrading over time may be examined using various
statistical time series analyses (e.g., temporal autocorrelation, spectral analyses).
Biological Resources: Vegetation Riparian habitats are known to support some of the most
diverse and productive ecosystems in the southwestern United States. However, it is estimated
that 75 to 95 percent of these natural systems have been lost due to development and water
diversion (Johnson and Haight 1984). Frequently the establishment of such habitats alone may
be perceived as an ecological benefit. In such cases, quantifying changes in the structure or
extent of a habitat through time (temporal trends) will allow an easily interpretable assessment
of the benefit of a discharge. In waterbodies where riparian habitats are not in limited supply,
the function of the habitat (e.g., ground water recharge) may provide an important ecological
benefit. In this case it is possible to assess changes in the relative value of a wetland or riparian
habitat (functional trends) either between locations or through time to demonstrate an ecological
benefit.
Temporal trends and the spatial extent of specific habitat types are used to demonstrate
that the occurrence or increases of these habitats is due to the presence of the discharge.
Functional trends are measured to compare the relative value of one habitat to another or to
assess changes in values of the same habitat over time. Wetland values might include the
provision of habitat for a specific species of concern, ground water recharge, production export,
etc. This type of assessment will provide the information necessary to evaluate the affect of
wetland or riparian habitats provided by a discharge on physical, chemical and biological aspects
of the waterbody.
Sampling equipment The primary sources of spatial information for evaluating long-term
temporal and functional trends are maps, aerial photography, and remote or satellite imagery.
These tools can serve as a simple visual aid for communicating the problem to the public.
Aerial or remote sensing can measure changes in acreage, cover types, and other spatial
parameters related to the overall extent and condition of a particular habitat type in a waterbody.
Although these data will frequently lack the information content to demonstrate the benefits from
2-52
-------
a particular discharge, they are well suited for establishing that the potential for a benefit (e.g.,
the loss of riparian habitats in a region).
i
There is very little equipment required for most vegetation field sampling techniques. In
general, data are obtained using either plots or plotless techniques, or a combination of the two.
Plots can be established using standard-sized quadrats (e.g., 1 m2) randomly placed along a
transect (SCS 1976). Photometers have been used to measure the amount of light penetrating
the vegetation canopy to estimate foliage density. Photographic techniques have also been used
to document long-term trends in vegetative cover density (Schemnitz 1980).
Conversion factors are available to convert plant species data from biomass per plot to
more common measures of production (e.g., pouads/acre or kilograms/hectare). Measures
should specify green weight or air-dry weight; factors for converting between green weight to
air-dry weight exist.
Analytical techniques The most straightforward approach for assessing trends in aquatic
habitats - and the one most typically used - is to document changes in habitat acreage (France
and Hedges 1989). Spatial data alone are particularly important because of the public concern
over declining habitat acreage in the southwestern United States. Physical and biological
attributes of wetland vegetation may be measured at regular intervals along a transect: point
intercept method (SCS 1976). Vegetation measurements might include basal cover, species
counts, relative foliage volume, foliage height diversity, litter height diversity, species
composition, and/or structural type (Anderson et al. 1977). The specific vegetation variable(s)
important to be measured in a given study will depend on the NEB Comparison objective. For
example, if provision of habitat for the violet-crowned hummingbird (Amazilia violiceps) were
considered an ecological benefit, the specific vegetation parameters) to be measured would be
dictated by known habitat preferences of that species.
Measures of cover are fundamental to measuring temporal trends in wetland and riparian
habitats. Basal cover at the erosion interface also provides information concerning retention of
2-53
-------
detrital material and potential for erosion (a functional trend). Basal cover complements
measures of productivity by providing information concerning the stability of the habitat. For
example, although a plant community may be highly productive, it may be susceptible to erosion
if there exists little basal cover at the erosion interface. This information may be used to guide
implementation of erosion control measures.
Functional measures of riparian and wetland habitats are most easily conducted using one
of several established habitat evaluation techniques. Most habitat evaluation techniques involve
some form of ranking, either quantitative or qualitative. Functional assessments usually describe
trends in water quality, hydrology, and biota that are potentially attributable to habitat loss and
impacts. Standardized, relatively rapid functional evaluation procedures generally provide
stronger replicability and technical comprehension.
Detailed, site-specific, functional assessment studies can be expensive, time-consuming,
and often impractical when time or budgetary constraints exist. Although more expensive,
correlating functional habitat losses to acreage loss is a more meaningful measure of the
condition of estuarine resources than acreage loss alone. Where time and budget allow,
implementation of detailed, carefully designed sampling programs or use of quantitative
computer models usually give superior-quality results. All functional assessment methods,
however, are limited by the level of understanding of the actual processes taking place in
habitats. These processes and their relative importance vary with habitat type, region, and
physical, chemical and biological conditions.
The Wetland Evaluation Technique (WET) and the Habitat Evaluation Procedure (HEP)
are two established methodologies for assessing the value and suitability of aquatic habitats for
various functions. The wetland functions and values that each of these methodologies are
designed to measure, as well as considerations for their application, are discussed in (U.S. EPA
1991). Specific guidelines for the use of WET are provided in Adamus et al (1987a and
1987b); and for the Habitat Evaluation Procedure in Lonard and Clairain (1986) and (U.S. FWS
1980). Many of the more recently developed habitat evaluation'methods are modified versions
2-54
-------
of these techniques. Modification of these techniques to suit the specific needs of conducting
an NEB Comparison may similarly be required.
The Wetland Evaluation Technique outlines the procedure for conducting an assessment
of the following wetland functions and values:
Ground Water Recharge Sediment Stabilization
Production Export Recreation
Ground Water Discharge Sediment/Toxicant Retention
Wildlife Diversity/Abundance Uniqueness/Heritage
Flood Flow Alteration Nutrient Removal/Transformation
Aquatic Diversity/Abundance
WET assesses functions and values by characterizing a wetland in terms of its physical,
chemical, and biological processes and attributes (Adamus et al. 1987). This characterization
is accomplished by identifying threshoW values for predictors. Predictors are simple, or
integrated, variables that directly, or indirectly, measure the physical, chemical, and biological
processes or attributes of a wetland and its surroundings. WET assesses the suitability of
wetland habitat for 14 waterfowl species groups, 4 freshwater fish species groups, 120 species
of wetland-dependent birds, 133 species of saltwater fish and invertebrates, and 90 species of
freshwater fish. WET does not evaluate any other important wildlife resources (e.g., game and
forbearing mammals). Other evaluation methods must be used to evaluate these other wildlife
resources (Adamus et al. 1987).
WET evaluates functions and values in terms of social significance, effectiveness, and
opportunity (Adamus et al. 1987). Social significance assesses the value of a wetland to society
due to its special designations, potential economic value, and strategic location. Effectiveness
assesses the capability of a wetland to perform a function due to its physical, chemical or
biological characteristics. Opportunity assesses the opportunity of a wetland to perform a
function to its level of capability.
2-55
-------
HEP is a method that can be used to document the quality and quantity of available habitat
for selected wildlife species. HEP provides information for two general types of wildlife habitat
comparisons: (1) the relative value of different areas at the same point in time; and (2) the
relative value of the same area at various points in time. By combining the two types of
comparisons, the impacts on, or improvement in habitat quality as a result of proposed or
anticipated land and water changes on wildlife habitat can be quantified (Lonard and Clairain
1986).
In using HEP, the habitat quality for selected species is documented based on an
evaluation of the ability of key habitat components to supply the life requisites of the selected
species. The evaluation involves using the same key habitat components to compare existing
habitat conditions and the optimum conditions for the species of interest (U.S. FWS 1980).
As part of the Chesapeake Bay National Estuary Program, minimum habitat guidelines
for various species were developed with the ultimate goal of reestablishing a balanced ecosystem.
This method, called the Minimum Habitat Matrix, is designed to provide information on the
minimum habitat quality needed by a target species and identifies those factors (both
environmental and ecological) required for the species (U.S. EPA 1991). This information is
formatted into a habitat requirement matrix that defines the habitat parameters needed for
successful reproduction and survival of the indicated species.
The Minimum Habitat Matrix technique can be used to identify vital environmental
parameters that should be used to assess the value of a particular habitat for a given species
(Chesapeake Executive Council 1988). Such a technique could be useful for identifying the most
important habitat parameters to measure in an NEB Comparison.
Data use There are a number of limitations to using a habitat approach, such as HEP, in an
evaluation system as was pointed out by the U.S. Fish and Wildlife Service (1980). Using
habitat quality as an evaluation standard limits the application of the methodology to those
situations in which measurable and predictable habitat changes are an important variable. It also
2-56
-------
forces a long-term "averaging" type of analysis. There is no assurance that populations will
exist at the potential levels predicted by habitat analysis, as the analysis may not include all of
the environmental or behavioral variables that may limit populations below the predicted habitat
potential. In addition, socio-economic or political constraints may prevent the actual growth of
certain populations to these levels (U.S. FWS 1980).
Data collected as part of biological surveys conducted during an NEB Comparison may
provide information useful in developing criteria for new or sub-divided designated uses. In
order to provide more comprehensive water quality programs, EPA has set a new priority for
establishing biological water quality criteria. In addition to providing more comprehensive water
quality programs, biological criteria can aid in subcategorizing aquatic life uses and evaluating
use attainment (U.S. EPA 19905). The initial phase of this program compels States to adopt
narrative biological criteria into State water quality standards during the FY 1991-1993 trienium.
The process for developing Biological Criteria is described in U.S. EPA (1990b). The first four
steps in this process are: 1) develop standard protocols, 2) identify unimpaired reference sites
and conduct biosurveys, 3) establish biological criteria, and 4) conduct biosurveys at impacted
sites. Provided the first three steps have been completed, the analyses conducted in a NEB
Comparison can be used to complete the fourth. Once this is done, the completed analyses can
be used to: 1) evaluate environmental benefits, and 2) aid in defining subcategories of a
designated use, if warranted, or 3) provide information useful in developing site-specific criteria,
if warranted.
2.5 Design of Monitoring Program for Verification of Net Ecological Benefit
Following a decision to modify the designated uses of a waterbody, a monitoring program
should be designed to verify that the Net Ecological Benefit identified by the NEB Comparison
is maintained. Monitoring objectives, program performance criteria, testable hypotheses, and
statistical methods can be derived directly from completed NEB Comparison tasks (Section 2.2),
since the purpose of the monitoring program is to provide information needed to assess whether
the Net Ecological Benefit identified by the NEB Comparison is preserved. This section
2-57
-------
identifies and describes monitoring program design tasks and data and information management
considerations.
A wide range of guidance on the design of environmental monitoring is available in the
literature. Important contributions have been made that address the principles and options for
designing monitoring programs (Green 1979; Segar and Stamman 1986), the development of
monitoring objectives (Beanlands and Dunker 1983), the appropriateness of monitoring variables
(Bilyard 1987), and the application of statistical methods in the design process (Ferraro et al.
1989). US EPA's Monitoring Guidance for the National Estuary Program (1991b) provides
a comprehensive overview of how to design a monitoring program that produces specific
information necessary to making environmental management decisions.
It is highly recommended that States/dischargers gain commitments to early and continued
participation and cooperation by local, State, and federal agencies, industry and environmental
interest groups, and the academic community in the development and review of the NEB
Comparison verification monitoring program. A standardized set of sampling and analytical
methods that meet program performance criteria should be established to ensure comparability
of data. Sampling and analytical methods used in ongoing monitoring efforts in the waterbody
and watershed ought to be considered when selecting monitoring methods. Standardization of
methods in the waterbody facilitates the sharing and use of data collected throughout the
waterbody.
2.5.1 Monitoring Program Design Tasks
The individual tasks involved in designing the monitoring program are :
Task 1 : Define monitoring objectives and performance criteria;
Task 2 : Establish testable hypotheses and select statistical analyses;
Task 3 : Select sampling and analytical methods;
2-58
-------
Task 4: Evaluate expected monitoring program performance and select appropriate
sampling design;
Task 5 : Implement monitoring program and data analysis; and
Task 6 : Verify Net Ecological Benefit and determine subsequent actions.
These tasks ensure that specific monitoring objectives, program performance, variables to be
measured, and data use are defined before any data are collected and analyzed.
Task 1 : Monitoring Program Objectives and Performance Criteria The overall
objectives of the NEB Comparison monitoring program are to provide the data necessary to:
Verify the Net Ecological Benefit identified by the NEB Comparison; and
Assess attainment of modified designated uses.
Because contaminant loading and bioaccumulation in valued waterbody resources is often a
potential concern (detriment) due to the presence of the discharge, monitoring of contaminant
sources and concentrations in aquatic habitats is frequently conducted. Thus, the NEB
Comparison monitoring program can often provide data to assess :
Compliance with effluent permit requirements; and
Compliance with ambient water quality criteria.
Explicit and succinct monitoring objectives specify the information needed to evaluate Net
Ecological Benefit and attainment of designated uses. They often identify relationships or
assessment endpoints that must be described in order to conduct an adequate assessment.
Specific monitoring program objectives can be derived directly from NEB Comparison
objectives, since the monitoring program must demonstrate continuance of Net Ecological
2-59
-------
Benefit (Table 2-5). Specific objectives with regards to attainment of designated use and
compliance, with water quality objectives can be explicitly defined by statements in the form of:
Demonstrate that designated use "x" exists ;
Demonstrate that ambient water concentrations of contaminant "x" do not exceed
"y" (where "y" is the water quality objective for contaminant "x" (Table 2-12).
Precise statements of designated uses will facilitate the development of testable hypotheses and
selection of sampling designs.
Once the objectives have been defined, expected monitoring program performance must
be specified. Expected performance criteria must define the differences between samples that
are to be detected by data analyses to demonstrate ecological benefit, detriment, or attainment
of designated uses. Specific DQOs and the power to detect differences or trends will be similar
to and can also be derived directly from NEB Comparison performance criteria (see Section
2.2.3). DQOs are specific, integrated goal statements developed for each information collection
activity to ensure that the data are of the required quantity and quality to meet their intended
uses. DQOs should specify the desired sensitivity of sampling methods, quality control/quality
assurance (QA/QC) data needed to interpret other data (e.g., method blank data), timing of
sampling, and numbers of samples collected. The selection and any future modifications of
monitoring methods should be directed by DQOs. EPA recommends that the State/discharger
submit their monitoring program to the NEB Comparison workgroup and members of the
academic community for technical review. Finally, the State/discharger must submit their
monitoring program to local, State, and federal agencies for review and approval.
Task 2 : Establish testable hypotheses and select statistical analyses To ensure that
appropriate and sufficient data needed to make management decisions are collected,
States/dischargers must specify, prior to the collection of any samples, testable (null) hypotheses
and statistical methods that will be used to analyze the resulting monitoring data. Specific
testable hypotheses will be similar to and can be derived from NEB Comparison testable
2-60
-------
Table 2-12
Example monitoring objectives
Monitoring objective 1: Demonstrate that flows contributed by the discharge result in the
maintenance of riparian habitats downstream of the discharge. (From NEB Comparison
objective 1).
Monitoring objective 2: Demonstrate that the waterbody sustains riparian habitats critical to
supporting breeding populations of the endangered violet-crowned hummingbird. (Modified
designated use).
Monitoring objective 3: Demonstrate that copper concentrations in aquatic habitats
downstream of the discharge do not exceed water quality objectives for copper. (Compliance
with water quality objectives).
2-61
-------
hypotheses (Table 2-6). Hypotheses for testing compliance with revised water quality criteria
should also be developed for each contaminant of concern and may take the form of :
Water concentrations of contaminant "x" are significantly greater than "y"
(where "y" is the water quality objective for contaminant "x").
Statistical Analyses Statistical tests must be specified for each hypothesis. The selection of
appropriate statistical analyses will depend upon null hypotheses, sampling design, and
distributions of the data.. Statistical analyses used in the NEB Comparison will probably be
appropriate for analyzing the monitoring data. Selected references that provide a discussion of
basic analytical options available and background information on the use of various statistical
methods are summarized in the annotated list in Table 2-7.
Analyses of the status and trends in Net Ecological Benefit will be of primary concern.
Statistical tests are available to handle :
Data assumed to be normally distributed and having no periodicity;
Data assumed to be normally distributed and having a known periodicity (i.e.,
monthly, seasonally, yearly);
Data assumed not normally distributed having no periodicity; and
Data assumed not normally distributed, yet having a known periodicity.
Time series plots can be used to show diurnal, seasonal, and annual patterns. Plots and
graphs, such as box plots and cumulative frequency distributions, can be used to display the
status and trends in environmental data (Figures 2-4 and 2-5, respectively).
It is highly recommended that a technical review of the statistical methods be conducted
by appropriate agency technical experts, members of the scientific community, and statisticians
to ensure acceptability of the analyses.
2-62
-------
Figure 2-4
Example box plot used to show distribution of data.
Box Plots for Column Xt
Concentration of Compound
i S i is 8 8 g 8 ! 1
. i i i _ . i . i . i . i ._ i . t .
* -, * m*fi«n *
o T 3 x bnarquwf ! rang*
o
o
o ^ nwfian*
!1.5 x intarquvtilo rango
mrtirt _ *""*" m»rquartile
rang*
[ ^ rrw*an-
1 .5 x trtarquartil* rang*
*^
-------
Figure 2-5
Example distribution of mercury concentrations in fish tissue.
20
40 60
Percentile of Sites
too
2-64
-------
Task 3: Select sampling and analytical methods The goal of this task is to develop detailed
monitoring program specifications. These specifications include selection of reference sites,
field collection and laboratory analysis methods, and appropriate QA/QC protocols. Ongoing
monitoring efforts in the waterbody and watershed ought to be considered when selecting
monitoring methods to ensure comparability to regional data. A standardized set of sampling
and analytical methods that meet program performance criteria must be established to ensure
comparability of data.
Reference and Study Sites Because benefits or detriments will be evaluated relative to
reference conditions, the selection of appropriate reference sites is critical to accurately assessing
Net Ecological Benefit. Reference sites are sites ecologically similar to study sites, however
they lack the influence of the discharge (see Section 2.3.1 Reference Sites). They provide
a control for the effects of the discharge on physical, chemical, and biological characteristics of
the waterbody. It is recommended that reference sites be located near the discharge to ensure
that environmental conditions are similar to sampling sites influenced by the discharge.
Field Sampling Methods A comprehensive compendium of field sampling methods is
presented in the EPA document, Monitoring Guidance for the National Estuary Program
(1991b). Although methods are discussed with respect to their use in estuaries, many are
applicable to riverine and other freshwater systems. The purpose of selecting field and
laboratory methods at this stage is to ensure that:
It is feasible to use selected methods in conjunction with the proposed level of
sampling effort;
Any data used to evaluate Net Ecological Benefit are directly comparable with data
that would be collected in the proposed monitoring effort; and
Standardized methods are selected.
2-65
-------
It is highly recommended that standardized sampling and analytical methods that meet defined
program performance criteria are selected to ensure comparability of data.
Since in many cases, bioaccumulation of discharge contaminants will be identified as a
potential ecological detriment, sampling of the effluent, ambient waters, and sediments will often
be required. Water quality samples should be collected at reference sites and at sampling sites
downstream below the mixing zone (Figure 2-6). Sediment samples should also be collected
downstream of the discharge to determine if any metals or organic chemicals are being
accumulated to levels that could be toxic to valued resources. The abundance and condition of
valued habitats and animal assemblages may also be surveyed to assess the potential adverse and
beneficial effects due to the discharge.
Laboratory Analysis Methods Considerations in selecting laboratory analytical methods include
desired detection limit, expected differences between values and criteria, possible matrix
interferences, preservation-holding time requirements, reliability, and costs. A detailed
discussion of currently available methods and their advantages and disadvantages is given in US
EPA's Monitoring Guidance for the National Estuary Program (1991b).
Quality Assurance and Quality Control (QA/QC) Protocols QA/QC is an integral part of all
environmental monitoring projects. A QA/QC project plan is required as listed in Table 2-13.
Guidance for developing such plans is discussed in several documents including the following:
Guidelines and Specifications for Preparing Quality Assurance Program Plans and
Quality Assurance Annual Reports and Work Plans for EPA National Program
Offices and the Office of Research and Development (EPA 004/87);
QAMS-004/80, Interim Guidelines and Specifications for Preparing Quality
Assurance Program Plans (1980);
Guidance for the Preparation of Combined Work/Quality Assurance Project Plans
for Environmental Monitoring (EPA 1984 OWRS QA-1);
2-66
-------
Figure 2-6
Example of preferred sampling locations near discharges. (US EPA, 1986a)
Sampling Locations
Aerial Vi«w of River
Sampling Locations
Discharge'
. S Vertical
7/f/'f//'f'fff''' "
Venice!
U Mixing
I 7«M
Zone
(b)
Side View of River
2-67
-------
Table 2-13
Essential Elements or a Quality Assurance Project Plan
1. Title Page (with EPA Project Officer, QA Officer)
2. Project Requested By
3. Date of Request
4. Date of Project Initiation
5. Project Officer
6. Quality Assurance Officer
7. Project Description
8. Project Fiscal Information (Optional)
9. Schedule of Tasks and Projects .
10. Project Organization and Responsibility
11. Data Quality Requirements and Assessments
12. Sampling Procedures
13. Sample Custody Procedures
14. Calibration Procedures and Preventative Maintenance
15. Documentation, Data Reduction, and Reporting
16. Data Validation
17. Performance and System Audits
18. Corrective Action
19. Reports
Based on EPA's Guidance for Preparation of Combined Work/Quality Assurance Project Plans for
Environmental Monitoring (QA-1)
2-68
-------
QAMS-005/80. Interim Guidelines for Preparing Quality Assurance Project Plans;
and
Guidance for the Preparation of Quality Assurance Project Plans for the National
Estuary Program (EPA 1988).
Critical aspects of sampling are setting appropriate data quality objectives, preparing and using
standard operating procedures for both field collection and laboratory analysis methods,
documenting all data collected using standard forms, and carefully evaluating all data received
from the laboratory. An example of forms used for documenting sample collection is shown in
Figure 2-7 and for data processing in Figure 2-8. Detailed guidance has been prepared
describing collection of additional QA/QC samples (e.g., method, field, and rinsate blanks;
matrix and blank spiked samples; analysis of standard MBS reference samples; and replicate
(duplicate) samples (e.g., U.S. EPA 1985,1986). Careful review of laboratory data packages
is also required including checking precision, accuracy, completeness, and representativeness.
Task 4 : Evaluate expected monitoring program performance and select appropriate
sampling design It is essential to assess expected program performance prior to collecting
the first samples. This performance information will provide the basis for determining the
feasibility of proposed sampling strategies. Questions that should be addressed are :
Can the proposed sampling effort meet the needs of the monitoring program as
defined by the monitoring objectives and performance criteria?
How can the proposed program be modified to ensure that these objectives are
met?
Alternative sampling designs include variations on the numbers and location of study sites,
sample frequency, and the level of sample replication. Proposed sampling designs, as well as
monitoring objectives, may have to be iteratively evaluated and modified until a sampling design
is developed to meet monitoring objectives. Tools for conducting these evaluations include
power-cost analyses.
2-69
-------
Figure 2-7
Example forms used for sampling: a) sample analysis request form, b) chain-
of-custody record, c) sample label, and d) custody seal.
TETRATECH.WC.
3746 ML Diablo Blvd. SuiM 300
Uf*y«ttt,CA 94549
41W8M771
BATCH
SAMPLE ANALYSIS REQUEST FORM
PACWMOUST
(An**
1. .
2. ,
t. .
10. .
11. .
12. .
11 .
14. .
IS. .
1C
17. .
It. .
«. .
10.
c)
T
E
T
R '
A
T
E
C
H
SAMPLE Ntt
PRESERVATIVE
SAMPLER DATE
PEA Investigations
TETRATECHtW.
3746 ML Diablo BM, Suto 300
Ufav*tM.CAMS49
41W8W771
BATCH
b)
NO,
sn
0»TI
TMI
MCCCWB«T:0i|MWI)
n
MCrotruoMU
MMUISvuMil
MTvnui
I
MTVTIMt
MTtfflMf |
d)
Tt
TETRA TECH, INC.
OFFICIAL SAMPLE SEAL
SAMPLE NO. DATE
SIGNATURE
PRINT NAME AND TITLE
-------
Figure 2-8
Selected example forms used in ODES QA/QC process.
DOES
Oeun Ota £*«>« Srm«i
SYSTEM QA REPORT
ooes
OoiwOiuC'
SYSTEM OA REPORT
Q -»
e »nw
Sw
Q MI»«*«|»IM
O Hl"»M »«!
e »»
*»« H '*< -D
nm D o >! D
eon
l«OOU
-------
The relative power of one sampling strategy with respect to another is more meaningful
when the relative costs of implementing alternative designs is taken into consideration. Analyses
of power-cost are fundamental in selecting appropriate sampling/replicate number, sample
location, and sampling frequency (Bros and Cowell 1987; Cuff and Coleman 1979; Ferraro et
al 1989); Millard and Lettenmaier 1986).
A cost function which describes the cost per replicate sample is required. Power-cost
formulations for parametric statistical analyses are of the form :
where:
i = a replicate sample collection and analysis strategy,
c = the cost per replicate,
n = the number of replicate samples, and
ft = the Type n error.
Costs will depend upon the sample collection, sorting, and analysis equipment and protocols.
Type n error OS) is a function of the number of replicate samples and the variance detected by
a sampling and analysis strategy. The measured variance may be influenced by the sampling
equipment used and the unit replicate sample size (e.g., as the unit replicate area increases,
variance increases).
Total costs are usually fixed. Therefore, iterations of power-cost formulations for various
strategies (e.g., sample collection, sorting, and analysis) and their comparisons will result in the
selection of the appropriate monitoring protocols and sampling design. Sokal and Rohlf (1981)
provide a series of formulas for calculating the most efficient sampling design for a given cost.
2-72
-------
Task 5 : Implement monitoring program and data analysis All sampling and analyses
finalized it. Task 4 should be conducted to provide the needed information necessary to evaluate
Net Ecological Benefit and attainment of designated uses. Test results and statistical power to
detect relationships for each analysis should be clearly reported.
Data analysis for water quality data is expected to focus on comparing observed
concentrations to criteria. This comparison can be made graphically as well as statistically. For
example, box plots and concentration vs. time plots can be made to show the distribution of the
data. Possible outliers can be flagged using these graphical techniques. Parametric or
nonparametric methods can then be used to detect statistically significant differences or trends
(see Sections 2.2.4 and 2.2.5).
Task 6 : Verify Net Ecological .Benefit and determine subsequent actions Annually, the
findings of the NEB Comparison monitoring program should be clearly reported; a discussion
of the program's conclusion, how information was used to reach the conclusion, and confidence
in making the determination should be clearly presented. During this phase, discussions between
the States/dischargers, representatives of regulating government agencies, and scientists will be
essential in determining Net Ecological Benefit. Peer review of the analyses by selected
members of the scientific community is strongly encouraged.
Water quality data collected may be used to determine compliance with the ambient water
quality criteria decided upon following the UAA analysis or development of site-specific criteria.
In addition to checking numerical criteria, an evaluation should also be conducted to determine
whether narrative criteria are met including maintenance of habitat specified by the designated
use. Particular care should be taken to confirm that non-aquatic species present in the study
reach are flourishing (e.g., amphibians, reptiles, waterfowl).
If the monitoring program does not meet program performance objectives, two alternatives
are available : 1) modify monitoring design to meet program objectives or 2) modify program
objectives and performance criteria to allow for feasibility in implementing the monitoring
2-73
-------
program. Iterations of modifying monitoring program design and performance criteria may be
required before a satisfactory program can be designed and implemented.
The monitoring program will also provide information to direct the States/dischargers
toward subsequent actions. If maintenance of a Net Ecological Benefit or attainment of
designated use is not demonstrated, management or enforcement actions may be taken by the
appropriate regulatory agencies.
2.5.2 Data and Information Management
Detailed documentation of field and laboratory procedures and careful recording of all
data is essential. Failure to plan for data management can result in the loss of the information
due to inadequate data preservation. The development of a data management system must
consider the following questions :
Where will the data go?
How will the data be stored? How will the data be retrieved?
Who will maintain the database?
How will the data be checked and loaded into the database?
How accessible will the data be?
Will the data be easily downloaded into statistical, graphical, and report generating
tools?
How much will it cost? Who will pay for it?
Standardized data storage and retrieval organization, formats, and codes is highly
recommended to facilitate analyses of data. How data are stored and retrieved in databases
supported by agencies or institutions investigating the waterbody should be considered before
2-74
-------
designing a database. Regional standardization of data storage and retrieval protocols and codes
will facilitate the sharing and use of all data collected in the waterbody. Simplified desktop
computer databases and electronic transfer between the laboratory and the State/discharger
responsible for the monitoring program can minimize transcription errors, incorrect reporting
of units, and speed up data transfer.
2-75
-------
CHAPTER THREE
DETERMINATION OF ECONOMIC AND SOCIAL IMPACTS OF
ATTAINMENT OF DESIGNATED USES
3.1 Introduction
This chapter provides guidance on how to incorporate the economic and social impacts
that are unique to effluent-dependent water bodies into the modification of water quality
standards. This guidance is relevant for Use Attainability Analyses (UAA) of water bodies in
arid sections of EPA Region IX (Arizona, California, and Nevada). Readers should consider
this guidance to be supplementary to Region IX's Guidance for Modifying Water Quality
Standards and Protecting Effluent-Dependent Ecosystems (1992). In some situations, wastewater
dischargers are the only source of water flow in effluent-dependent water bodies during parts
of the year. As a result, the cost of pollution reduction technologies in these water bodies may
be prohibitive to many dischargers. Additionally, the development of beneficial water
reclamation projects that would require some discharge to water bodies may also be discouraged.
The federal Clean Water Act of 1987 and its regulations establish several methods for modifying
standards and permits that address the unique circumstances of effluent-dependent water bodies
while ensuring that existing uses are fully protected.
In addition to, or as an alternative to considering Net Ecological Benefit,
State/dischargers may want to consider any economic conditions that may preclude the
attainment of designated uses in effluent-dependent water bodies. By demonstrating in their
UAA that attaining the designated use would cause substantial and widespread adverse economic
and social impacts, State/dischargers may be able modify a water body use, thereby relaxing
water quality based permit requirements in the water body. State/dischargers should keep in
mind, however, that a designated use may only be modified if it is not an existing use.
Dischargers must already be meeting all technology based limits. Water quality may not be
lowered below that which protects existing uses. In addition, the discharger must be able to
3-1
-------
prove that their discharge will not create adverse environmental effects in downstream
waterbodies or in groundwater basins.
Under the Clean Water Act, the economic impacts that can be considered, are those that
result from treatment beyond that required by technology-based regulations. Since water quality
cannot be lower than that resulting from technology based limits applied to direct and indirect
point source discharges, these are considered baseline.1 All economic feasibility analyses done
for UAA's should, therefore, address only the incremental cost of meeting water quality
standards. A checklist of the steps dischargers are required to undertake in demonstrating
substantial and widespread economic and social impacts is provided in Table 3-1. This checklist
also presents the type of data dischargers need to collect to support each step.
To demonstrate adverse impacts, an economic feasibility analysis must be completed
either by the State or by the discharger and reviewed and approved by the State, to assess the
magnitude and extent of potential economic impacts. All economic feasibility analyses must also
be reviewed and approved by the US EPA Region DC Administrator. EPA will consult with the
US Fish and Wildlife Service on all water quality standards actions. EPA encourages
dischargers to coordinate their analysis with EPA throughout the UAA process. Specifically,
EPA suggests that dischargers submit a proposal to them and to the State describing the intended
methodology and a schedule for undertaking the study. In addition, before any change in use
is approved, a period of public comment and debate must be held. During this period, the
general public is encouraged to comment on whether or not they feel the potential socioeconomic
impacts resulting from compliance with water quality standards warrants changing a use.
The UAA must demonstrate that the entity (whether privately- or publicly-owned) is not
able to afford necessary pollution reductions. In addition, the analysis must show that the
surrounding community is adversely affected if the entity is required to meet water quality
standards calculated to protect the designated use for which modification is sought. Throughout
'This supplementary guidance does not apply to non-point source discharges.
3-2
-------
Table 3-1 CHECKLIST (Cont'd.)
STEPS
INFORMATION THAT WILL BE REQUIRED FROM
APPLICANT
Evaluate entity's
Only):
solvency,
financial health (Private Entities
liquidity,
leverage, and
earnings.
Evaluate entity's
Only):
financial health (Public Entities
determine method of financing,
Information that will allow evaluation of the entity's ability to pay its
fixed and long-term obligations including:
long-term debt,
current debt,
net income after taxes, and
depreciation.
Information that will allow evaluation of how easily an entity can pay its
short-term bills such as:
current assets,
current liabilities, and
total annualized pollution reduction project costs.
Information that will allow evaluation of the extent to which a firm
already has fixed financial obligations and therefore how much money
it will be able to borrow including, long-term liabilities and owner
equity.
Information that will allow evaluation of whether an entity will remain
profitable after incurring the cost of pollution reduction including:
revenues,
cost of goods sold,
portion of corporate overhead assigned to the entity, and
total annualized pollution reduction project costs.
Information on Revenue Bonds, General Obligation Bonds, Bank Loans.
3-4
-------
Table 3-1
Demonstration of Substantial and Widespread
Economic and Social Impacts of Attainment of Designated Uses
CHECKLIST
STEPS
INFORMATION THAT WILL BE REQUIRED FROM
APPLICANT
Demonstrate that designated use is a potential use and not an Data from California Regional Water Quality Basin Plans,
existing use. Water Quality Assessment Document and standards regulations
for Arizona, and the Nevada water quality standards
regulations.
Demonstrate that entity cannot afford cost of pollution Information on end-of-pipe treatment, possible treatment upgrades,
reduction. additions to existing treatment, and pollution prevention activities
including the following:
a. Identify all reasonable pollution reduction options.
change in raw materials,
substitution of process chemicals,
change in process,
water recycling, reuse and efficiency,
pretreatment requirements, and
public education.
Evaluate costs of all reasonable pollution reduction Assumptions about water demand, treatment capacity, expansion plans,
options. population growth, and effectiveness of control in reducing pollution for
each option. Estimate of project costs from design engineers, costs of
comparable projects in the State, or judgement of experienced water
pollution control engineers.
Identify lowest cost pollution reduction option that Information on treatment efficiencies for alternative pollution reduction
otjows <»"tJty to meet watex qualitv standards. techniques. Cost estimates for all alternatives.
-------
Table 3-1 CHECKLIST (Cont'd.)
STEPS
INFORMATION THAT WILL BE REQUIRED FROM
APPLICANT
4.
5.
6.
7.
8.
9.
d.
e.
f.
Evaluate effect on tax revenues.
Assess impairment of development opportunities.
Information on the likely effect on assessed value of property tax
revenues if the entity must adopt pollution reductions.
Information on the likelihood that the need to adopt pollution reductions
in the affected community would discourage other businesses from
locating in the area in the future.
Collect any relevant additional information that Any additional information that suggests that there are unique conditions
demonstrates widespread socioeconomic impacts. in the affected community that should also be considered.
Public Comment and Debate Period.
Be prepared to supply backup information on the UAA to the public
If substantial and widespread economic and social impacts are Information on the cost and efficiency of affordable pollution reduction
demonstrated, determine which pollution reduction option alternatives.
should be implemented.
Redesignate uses.
Standards will be adopted to protect new uses.
Effluent limits and permits will be modified.
Re-evaluate Use Attainability Analysis in three years.
Uses will be determined by the level of "affordable" pollution reduction.
Once uses are established, standards should be revised to protect those
uses.
Limits will be modified to reflect effluent concentrations associated with
the "affordable" pollution reduction technique.
Per federal regulations, the UAA must be revised every three years to
determine if there is any new information or technology that allows
attainment of the full designated uses without causing a substantial and
widespread economic and social impact.
3-6
-------
Table 3-1 CHECKLIST (Cont'd.)
STEPS
INFORMATION THAT WILL BE REQUIRED FROM
APPLICANT
median household income,
f.
Current estimates of median household income in the affected
community.
annual debt service as fraction of annual revenues, and Information on the communities existing annual debt service, the
expected annual debt service associated with the proposed project, and
current tax revenues.
annual debt service as fraction of market value of Information on the communities existing annual debt service, the
taxable property. expected annual debt service associated with the proposed project, and
market value of assessed taxable property in the affected community.
Collect any relevant additional information that Information that may suggest that there are unique conditions in the
demonstrates entity cannot afford cost of pollution community that affect affordability such as limits on annual property tax
reduction. increases and other financial information such as user fee rate structure,
revenues.
3. Assess socioeconomic impact to community.
a. Define community.
b. Evaluate effect on employment.
c. Evaluate effect on water reclamation.
For public entities, information on the geographical boundaries of the
sewage/water district. For private entities, information on the
geographical boundary of the area in which the majority of the entity's
workers live and where most of businesses that depend on the entity are
located.
Current unemployment, change in unemployment due to investment in
pollution reduction.
Evidence that the cost of pollution control may prohibit the construction
and operation of water reclamation projects that would result in water
conservation.
-------
this chapter, the term "entity" refers to the wastewater discharger. In addition, the term
"financial impacts" refers to impacts on the entity that pays for pollution reduction, whereas the
term "socioeconomic impacts" refers to impacts on the affected community.
The methods that are appropriate for evaluating the economic impacts of meeting water
quality standards depend, in part, upon whether the polluting entity is privately- or publicly-
owned. EPA considers privately-owned entities to include but not be limited to: manufacturing
facilities, agricultural operations, commercial development, and recreational development.
Similarly, EPA considers publicly-owned entities to include: publicly-owned sewage treatment
works, highway and public works departments and other such governmental agencies that are
publicly financed. Depending on the water body, several dischargers may suffer and claim
economic hardship from the same water quality standard. In an economic impact analysis the
distinction between public and private entities is critical as it dictates who ultimately pays for
the necessary pollution reductions as well as the types of financing mechanisms available.
The Office of Science and Technology (Office of Water), US EPA has developed detailed
methodological guidance (in the form of a draft Water Quality Standards Workbook) on the
measurement of the financial and socioeconomic impacts of complying with water quality
standards. This guidance does not, however, address the unique circumstances associated with
effluent-dependent water bodies. The pujpose of this supplementary guidance, therefore, is to
address these unique circumstances in effluent-dependent water bodies. Reference to the
Workbook, however, is also recommended. The Workbook includes a series of worksheets and
accompanying guidance that applicants can use to calculate the impacts of pollution reduction.
i
Specifically, the Workbook includes worksheets that address: 1) the estimation of annualized
costs of pollution reductions, 2) the affordability of pollution reductions, and 3) the evaluation
of whether impacts to the entity will result in substantial and widespread economic and social
impacts. The draft Workbook can be obtained by contacting the Office of Science and
Technology (Office of Water), US EPA, Washington, DC. Revisions to the draft Workbook
are currently underway. The Office of Science and Technology expects revisions to be
completed sometime in Fiscal Year 1993. State/dischargers should always check with EPA
3-7
-------
Region IX or with the Office of Science and Technology to make sure they are using the most
up-to-date version of the workbook.
3.2 Evaluating Treatment Options That Would Allow the Discharger to Meet Water
Quality Standards
The first step in conducting the economic feasibility analysis is to identify all options
(technological or otherwise) for meeting applicable standards for the water body in question.
State/dischargers should consider a broad range of discharge management options including
pollution prevention, end-of-pipe treatment, and upgrades or additions to existing treatment.
Specific types of pollution prevention activities that should be considered are:
Change in Raw Materials;
Substitution of Process Chemicals;
Change in Process;
Water Recycling and Reuse;
Pretreatment Requirements; and
Public Education (mainly public entities).2
Whatever the approach, the State/discharger must demonstrate that the proposed project is the
most appropriate means of meeting water quality standards and must document project cost
estimates. Finally, if the entity can afford at least one of the treatment alternatives that allows
them to meet water quality standards, they are not able to demonstrate substantial financial
impacts. Demonstration of widespread economic and social impacts is then moot and the entity
. 'The general public should be educated about the types of wastes that should not be flushed down the drain.
In addition, agricultural operations might be instructed that reductions in pesticide and/or fertilizer use can improve
the quality of irrigation return water.
3-8
-------
is required to meet existing standards. Alternatively, the entity may still consider whether there
are other physical, chemical or site-specific factors that preclude attainment of the designated
use.
As part of the evaluation of possible treatment/pollution reduction options, it is necessary
to estimate and document the costs of alternatives being given final consideration. Submissions
should include assumptions about excess treatment capacity, expansion plans/population growth,
and effectiveness of control in reducing pollution. The most accurate estimate of project costs
may be available from the applicant's design engineers. If site-specific engineering costs are not
available, preliminary project cost estimates can be derived from a comparable project in the
State or from the judgement of experienced water pollution control engineers. The analysis
should also specify assumptions related to financing of the project costs.
For comparative purposes, the cost estimates (i.e., capital, O&M, and other project costs)
for each alternative being considered should be presented in the same units (typically normalized
cost, $/year) and same year dollars. The draft Water Quality Standards Workbook details how
to annualize capital costs and how to calculate annualized project costs for private and public
projects. The State/discharger needs to collect information such as capital costs to be financed,
interest rates, time period of financing, annualization factors, and operating and maintenance
costs to calculate annualized project costs. Once the least cost alternative allowing
State/dischargers to meet water quality standards has been identified, the discharger should focus
the remainder of the economic feasibility analysis on that pollution reduction option. If the
State/discharger feels that the least cost alternative is not affordable, they should undertake the
financial analysis presented in the next section. This analysis will be reviewed by EPA as part
of their evaluation of whether the applicant has been able to demonstrate substantial and
widespread economic and social impacts.
3-9
-------
3.3 Measuring Financial Impacts
As described above, the economic feasibility analysis must demonstrate two conditions.
First, it must demonstrate that the State/discharger cannot afford the necessary pollution
reduction investments (i.e. there are substantial impacts). Second, it must demonstrate that if
the discharger is required to meet water quality standards, significant adverse economic and
social impacts to the surrounding community will result (i.e., there are widespread impacts).
Guidance on evaluating financial impacts is presented in this section.
In general terms, financial impact analyses focus on the ability of an entity to pay for the
necessary pollution reduction. If a private entity were unable to pay for improved wastewater
treatment, it might decide to close production lines or close the entire operation. Alternatively,
the entity may decide not to undertake a water reclamation project, thus forgoing important
water conservation benefits. A public entity may have to raise user fees or property taxes to
cover the cost of the necessary pollution reduction.
Specific factors to consider depend upon whether the discharger is a public entity (such
as a municipal sewage treatment plant) or a privately-owned entity (such as a manufacturer).
An important consideration in determining an entity's ability to pay is its source of funds. In
the case of a private entity, the analysis should measure a number of factors including: the extent
to which the facility is able to secure loans or must rely on equity funds, and the degree to
which it can pass the cost of pollution reduction on to consumers in the form of higher prices.
In the case of a publicly-owned entity, the analysis should consider whether treatment costs can
be covered by raising the fees paid by users or by tax increases. To estimate the ability of a
private entity to finance necessary pollution reductions, the State/discharger should use economic
ratios that measure various characteristics of the firm's financial health and its ability to pay for
the pollution reduction. Several such measures are presented in the next section. In either case,
public or private, when EPA receives the UAA they may employ an auditor to review the
State's/discharger's financial impact analysis.
3-10
-------
For most public entities the burden on rate or tax payers, rather than closure, is the major
concern. The proper choice of measures of the financial condition of a public entity depends
on how the entity pays for necessary pollution reductions. If treatment is financed by raising user
fees (as would occur with revenue bond financing), the ratio of user fees (both current fees and
incremental fees required to pay for additional treatment) borne by households to median
household income provides an estimate of the burden on the service area of complying with
water quality standards. If, on the other hand, the project is financed through local taxes (as
would occur with general obligation bond financing), the ability of the community to meet its
debt service obligation can be evaluated by estimating the ratios of debt service to total revenues
and of debt service to market value of taxable property. Each of these ratios, as well as other
applicable economic ratios, is discussed in greater detail below.
3.3.1 Measuring Financial Impacts To Private Entities
A financial impact analysis is performed using financial data specific to the entity that
pays for the pollution reduction. The purpose of the analysis is to assess the extent to which an
entity is adversely affected by pollution reduction investments, possibly curtailing its operations,
deciding not to undertake a water reclamation project and reducing employment in response to
water quality standards. This analysis examines the entity's ability to pay for the required
additional treatment over the short- and long-term. The analysis uses four general categories
of tests: liquidity, solvency, leverage, and profit measures. Profit and solvency ratios are
calculated both with and without the additional compliance costs (taking into consideration the
entity's ability, if any, to increase its prices to cover part or all of the costs). Comparing these
ratios to each other and to industry benchmarks provides a measure of the entity's ability to
afford the additional treatment.
In all of the tests, however, it is important to look beyond the individual test results and
evaluate the specific situation of the entity. While each test addresses a single aspect of financial
health, the results of the four tests should be considered jointly, to obtain an overall picture of
3-11
-------
the economic health of the entity and the impact of the water quality standards requirement on
the entity's health. The results should be compared with the range of ratios which can be found
among other entities in the same industry or activity. Ratios and tests also should be calculated
over several years of entity operations. This will allow long-term trends to be differentiated
from short-term conditions in the entity's financial standings. The structure, size, and financial
health of the parent firm should be considered. Another important factor is the value of an
entity's product or operations to its parent firm which may not be reflected in the preceding
measures. For example, if an entity produces an important input into other entities owned by
the firm, the firm may be more likely to support an entity with borderline profitability. The
results of these tests and other relevant factors, can be used to make a judgement as to the likely
actions of the entity (e.g. shut down entirely, close one or more product/service lines, shift to
other products/services, not proceed with an expansion, continue operations at current levels)
faced with the pollution reduction investment.
While these tests should reflect the entity's operation, the information required is detailed
and may not be available at the entity level. As an example, revenues from products and
overhead costs are two types of data that entities often do not collect. Frequently, these items
are known for the entire firm but must be estimated for the individual entity. When this
information is calculated at the entity level, it is important that the calculation is based on
current market values. Even if the entity does not sell or buy materials directly on the market,
the materials are available somewhere in the economy and the market prices should be used.
In addition, the entity level information required may be considered confidential by the owners.
It is EPA policy, however, that applications based on economic considerations must be
accompanied by data that demonstrate the impacts. In such cases, confidentiality will be
protected.
This discussion of economic tests centers around the determination of financial impacts
for a single entity; if more than one entity is affected, then the financial impacts on each entity
should be evaluated separately. Analysis of the socioeconomic impacts (discussed in Section
3.4) should take into account the combined effects of the impacts on all entities that are being
3-12
-------
considered. In addition, while this discussion focuses on impacts on existing entities, the same
tests and analyses can be used to measure impacts on proposed entities. This point is relevant
in cases where a request to downgrade a use is based on the relative impacts of important
economic development.
Each of the four general categories of financial tests is described below, along with an
example of a specific measure to be used. In most cases, interpreting the results requires
comparisons with typical values for that industry. Among the sources that provide comparative
information are: Robert Morris Associates' Annual Statement Studies and Moody's Industrial
Manual. The Annual Statement Studies provide composite statistics for firms grouped by
different manufacturing and service industries. The Moody's Industrial Manual provides detailed
financial information on individual firms. The following tests are discussed in greater detail in
the Office of Science and Technology's draft Economic Guidance for Water Quality Standards
Workbook. Worksheets are also provided in the Workbook to be used when actually calculating
the impacts of poJJution reduction. All the information necessary to calculate these impacts
should be available on company balance sheets and/or in company annual reports. Although
benchmarks are available for most financial tests, EPA emphasizes that the State/discharger
should consider these benchmarks as indicators of financial health and not as definitive measures.
Liquidity is a measure of how well an entity can pay its short-term bills. This assessment
is achieved by comparing current assets to current liabilities. Current assets include cash and
assets that could reasonably be converted into cash within the current year. Likewise, current
liabilities are items that must be paid within the current year.
One measure of liquidity is an entity's Current Ratio, calculated as follows:
Current Ratio = Current Assets/Current Liabilities
The general rule is that if the Current Ratio is greater than two, the entity should be able to
cover its short-term obligations. Frequently, lenders require some level of liquidity as a
3-13
-------
prerequisite for lending. While a current ratio of greater than two indicates that the entity can
probably is cover its short-term obligation, whether or not the entity is able to afford a major
capital investment such as the pollution reduction project must be judged in conjunction with the
other three affordability measures described in this guidance.
Solvency tests measure the ability of an entity to pay its fixed and long-term obligations.
These obligations are bills and debts that an entity owes on a regular basis for periods longer
than one year. Solvency tests can also be used to predict financial problems that could lead to
bankruptcy within the next few years. SoWency tests must be considered over several years of
data in order to reveal long-term trends of the entity. A single year of data may be distorted
by one-time events. Solvency ratios compare earnings or cash flow to fixed obligations. A
comparison of solvency values before and after control costs demonstrate the relative impacts
of pollution reductions on a entity's long-term ability to carry its debt. One commonly used
solvency test is the Beaver's Ratio.
Beaver's Ratio = Cash Flow/Total Debt
Cash flow is a measure of the dollars the entity has available to it in a given year. Since
depreciation is an accounting cost - a cost that does not use any currently available revenues -
- it is added back to reported net income after taxes to get cash flow. Total debt is equal to the
current debt for the current year plus the long term debt, since current debt includes that part
of long-term debt that is due in the current year. If the Beaver's Ratio is greater than 0.20 the
entity is considered to be solvent (i.e. can pay its long-term debts). If the Ratio is less than
0.15, the entity may be insolvent (i.e. go bankrupt). When the Ratio is between 0.15 and 0.20,
future solvency is uncertain.
Leverage tests measure the extent to which an entity has fixed financial obligations and
thus indicate how much more money an entity is capable of borrowing. Companies and entities
that are already heavily in debt find it difficult and expensive to borrow additional funds. The
debt to equity ratio is the most commonly used measure of an entity's leverage.
3-14
-------
Debt/Equity Ratio = Long-Term Liabilities/Owners' Equity
The ratio measures the total amount an entity has borrowed relative to the amount of capital
which is owned by stockholders. Typical debt to equity ratios are different for different
industries. The results of the analysis should be compared with industry averages and the
entity's performance over time. Since the debt to equity ratio evaluates the ability of an entity
to take on more debt, it is not adjusted for the costs of pollution reduction. There are no
generally accepted Debt/Equity Ratio values that apply to all types of economic activity. As a
result, this ratio should be compared with debt/equity ratios of similar firms.
Profit Measures test whether or not the costs of pollution reduction makes an entity
unprofitable, where profits are defined as earnings before taxes. An entity that can pay for all
of its fixed and variable costs will remain in operation in the long-term. In order to evaluate
the impacts of pollution reduction costs, the annualized pollution reduction costs are subtracted
from the entity's earnings before taxes for the most recently completed fiscal year. Comparing
the before and after pollution reduction cost results suggests the impacts of pollution reduction
costs on the profitability of an entity. A commonly used profit measure is called the Profit Test.
Profit Test = Earnings Before Taxes/Revenues
Earnings before taxes should be calculated for at least the three previous fiscal years in order
to identify any trends or atypical years. Earnings with pollution reduction costs should be
calculated for the last complete year of financial information. Inflation may make a comparison
of earnings before taxes and the annualized cost of pollution reduction invalid for the previous
years. In its simplest form, as long as the entity maintains positive earnings, the entity can
afford to pay for the pollution reduction.
In interpreting the results of a financial impact analysis, the last test, the Profit Test, may
be the first one to look at it gives an indication of what happens to the entity's earnings if
additional pollution reduction is required. If the entity is making a profit now but will not if
3-15
-------
required to pay for a water quality based pollution reduction project, then the possibility of a
shutdown must be considered. Likewise, in the case of a proposed entity, if it would make
money without the pollution reduction investment but lose money with it, then the development
might not take place. An alternative to a complete shutdown might be closing the operations
(e.g. a production line) that require the pollution reduction. In either case, there is the chance
that employment will be lost and local purchases by the entity reduced.
There are several, more complicated scenarios that might arise from this analysis. They
all involve making a judgement as to the likely impacts on the entity, including questions of the
timing of compliance. For example, the Profit Test may indicate that the entity continues to be
profitable after compliance, but the Debt/Equity Ratio may indicate that they will have trouble
raising the required capital through debt. This problem may be solved by giving them more
time to meet the regulations (a variance), so that they can restructure their debt and/or find
alternative sources of funds. It should be kept in mind, however, that in order for a variance
to be granted, the entity is still required to conduct a similar type of economic feasibility analysis
that is required by a UAA. Additionally, unlike a UAA which addresses the affordability of
meeting water quality criteria for a whole array of pollutants, a variance may only apply to one
pollutant. The discharger must still meet water quality criteria for all other pollutants. In
another case, the entity might argue that while they will still make money and be able to raise
the needed capital, they would alternatively spend those funds on an expansion which would
have resulted in increased employment and income for the community. This is a more difficult
situation to analyze, and depends on judgements about the relative importance of the water
pollution reduction versus economic growth. This is a case where public participation by the
community is particularly important to EPA in their decision-making process. In each case it
is important to take the entire picture presented by the four ratios into account in judging
whether or not the entity can afford the necessary reductions. If it is determined that the entity
can afford the necessary pollution reductions, the entity must meet existing standards.
Alternatively, they may still consider whether there are other physical, chemical, or site-specific
factors that preclude attainment of the designated use. If the State/discharger feels that, based
3-16
-------
on this analysis, it cannot afford the pollution reductions, widespread economic and social
impacts must be demonstrated.
3.3.2 Measuring Financial Impacts To Public Entities
As with private entities, public entities seeking relief from meeting water quality standard
requirements must, as a first step, demonstrate that they cannot afford the cost of necessary
water pollution reductions. The State/discharger can use the following three types of measures
to determine if a publicly-financed project imposes substantial economic impacts on a
community.
The ability of households within the community to afford the added costs of the
pollution reduction project. The ability of non-residential users to afford their
share of the added costs is measured using the tests described in the private entity
section.
The ability of the public entity to obtain debt financing for the capital cost of the
pollution reduction project.
Other factors such as financial and economic impact indicators that characterize
the economic well-being of the community, debt history, current rate or user fee
structure, revenues collected by the POTW and other relevant information that
would indicate a public entity's ability to pay for pollution reduction costs.
Although benchmarks are available for most financial tests, EPA emphasizes that the
State/discharger should consider these benchmarks as indicators of financial health and not as
definitive measures.
To evaluate economic and financial impacts, the State/discharger must define the affected
community. The term "community," is the governmental jurisdiction responsible for paying
compliance costs. In practice, pollution reduction projects often serve several communities or
just portions of a community. In the case of a sewer agency serving several communities, once
3-17
-------
project costs are allocated to each community served (and added to existing sewerage charges),
the same economic analysis is conducted on a community by community basis. Where only a
portion of a municipality is served, the affected community is defined as those who will pay the
compliance costs.
For a publicly-financed project, the project's capital financing mechanism and allocation
of project costs play important roles in distributing costs, and thus impacts, within the
community. Typically, publicly-financed project costs are repaid through user fees (only users
of the project pay) or property tax revenues (all property owners in the community pay). The
capital portion of project costs is often financed over a time period of approximately 20 years,
by issuing a municipal debt instrument such as a revenue bond or a general obligation (G.O.)
bond. A G.O. bond is backed by the full faith and credit of the community. Conversely, a
revenue bond is usually issued by a water or sewer authority and depends on the authority's
ability to generate enough revenues (user fees) to pay interest and retire the principal.
If capital costs are financed through issuing a revenue bond, then capital and annual
O&M costs are recovered entirely through user charges and the financial capability analysis
should focus on the project's impact on various ratepayers. The total annual cost of the project
includes the annualized capital (using interests rates appropriate for revenue bond financing) and
the annual O&M costs. The following measure should be used:
Average annualized cost per household as a percentage of median household
income. This measure evaluates expected impacts on what is considered to be the
most sensitive user group households. (These costs include only that part of
the pollution reduction investment that is borne by households, not that portion
borne by non-residential indirect dischargers).
Alternatively, if capital costs are financed using general obligation bonds (or some other
debt instrument repaid from general tax revenues), the focus of the affordability analysis is the
local government's ability to bear its increased debt burden (in addition to households' ability
to pay for their share of project costs - debt burden and recurring annual costs). When the
3-18
-------
financing mechanism is general obligation bonds, two measures should be employed. The
average annualized cost per household as a percentage of median household income, as
described above, should be reviewed in conjunction with the following measure:
Annual debt service as a fraction of annual revenues. This measure evaluates
the relative increase in revenues needed to pay for the increased debt burden.
(These costs include the total cost of the pollution reduction investment).
Local governments may also finance capital costs using bank loans, State infrastructure
loans (revolving funds), or federally subsidized loans (such as those offered by the Farmers'
Home Administration). Detailed guidance on using these measures can also be found in the draft
Economic Guidance for Water Quality Standards Workbook available from the Office of Science
and Technology in the Office of "Water at EPA Headquarters. If the financing method is not
known, and there are no known restrictions on how a projects may be financed, then the two
evaluation measures described above plus the following measure should be used.
Annual debt service as a fraction of market value of taxable property. This
measure evaluates the ability of the property tax to generate sufficient tax
revenues to support the increased debt burden. (These costs include the total cost
of the pollution reduction investment).
To determine the project's affordability, EPA has established threshold values for each
of the three measures listed above. For the first measure, average annualized cost per
household as a percentage of median household income, if the average annual cost per
household (debt burden plus recurring annual costs) is less than one percent of median household
income, then the project is not expected to create economic hardship on households. If the
average annual cost per household exceeds two percent of median household income, then the
project may place an unreasonable financial burden on many of the households within the
community. The range between one and two percent is considered a grey area. In such cases,
other factors such as the wealth of the community, percentage of households below the poverty
3-19
-------
line, and unemployment rate are of particular interest. This measure is used in all cases,
regardless of how the pollution reduction investments are financed.
The second two ratios measure the percent of local property tax burden needed to cover
the pollution reduction project. These two ratios are used when the pollution reduction
investments will be financed either through the municipality's general revenues or through
property taxes. When both benchmarks are exceeded the government may have difficulty issuing
a general obligation bond to finance the capital costs of the proposed project. Annual debt
service as a fraction of annual revenues measures the ability of a municipality to pay for
increased debt service with available revenues. If the new project causes the total annual debt
service (baseline plus additional debt associated with pollution reductions) to exceed the
threshold of 0.20 (20 percent), then the community may not have the necessary tax base to
support other (non-debt) municipal services. It might then be necessary for the municipality to
raise the tax rate to pay for the increased debt service.
Since the property tax is often the major source of local tax revenues, the annual debt
service as a fraction of market value of taxable property is used to determine if total debt
service can be supported by the municipality's revenue base. 'The threshold value of 0.008 (0.8
percent) for the ratio of general obligation debt service to market value of taxable property is
considered the limit of acceptable tax burden for property. Ratios higher than the threshold
indicate that the total debt service exceeds the amount that can reasonably be supported by the
tax base. Both of these thresholds were established by looking at these ratios for a variety of
communities with Baa bond ratings (i.e. the lowest investment grade bond rating). If both
thresholds are exceeded, then the municipality may be unable to issue general obligation bonds,
or may have to pay excessively high interest rates, to finance the capital portion of the pollution
reduction project.
In addition, there are several other issues to consider when interpreting the affordability
criteria for general obligation bond financing. First, limits on annual property tax increases may
be an insurmountable hurdle for local governments in several States. That is, while the criteria
3-20
-------
may not exceed the thresholds, constitutional, statutory or charter limits may prevent the
required tax increase. Second, other local revenue sources, such as income from mineral rights
of local government property or payments in lieu of taxes, should also be considered in the
evaluation of the burden of debt service.
In performing economic analyses, effort should be made to collect and use several years1
worth of information because of the year-to-year variability in debt service, outstanding debt,
and municipal revenues. If information is available for only one year, care should be taken to
ensure that the information is representative of the municipality's financial situation.
It is also important to consider the impacts of a publicly-financed project on sensitive
indirect industrial dischargers, those with a large contribution to influent flow and/or those to
whom the municipality might turn to recover compliance costs. If pollutant surcharges are in
effect, industrial sources pay more per unit discharged than households pay, due to higher
pollutant loadings. On the other hand, a declining rate structure results in large industrial
sources paying less per unit discharged than smaller dischargers. In addition, user fees and
surcharges for industrial facilities with large wastewater flows may be particularly sensitive to
unit increases in those costs. Where the municipality plans to recover some or all of the costs
of additional pollution reductions from industrial sources, it is important to consider the impact
of cost increases for indirect industrial dischargers as outlined in the private entity impact section
above. If it is determined that the public entity can afford the necessary pollution reductions,
the entity must meet existing standards. Alternatively, they may still consider whether there are
other physical, chemical, or site-specific factors that preclude attainment of the designated use.
If the State/discharger feels that, based on this analysis, it cannot afford the pollution reductions,
widespread economic and social impacts must then be demonstrated.
3-21
-------
3.4 Measuring Socioeconomic Impacts
The financial impacts of undertaking pollution reduction could potentially cause far-
reaching and serious socioeconomic impacts. In the case of an effluent-dependent stream such
impacts include the loss of a planned water reclamation project that could augment necessary and
existing water supplies. One important factor in determining the magnitude of these impacts is
defining the geographical area in which they occur. In some cases, one community's loss may
be another community's gain, as in the case of a plant moving to another community.
In the case of a public entity, the most relevant area is usually the sewage/water district
or municipality, including households, commercial entities, and industries, that pays for the
pollution reductions. An analysis of impacts from compliance by a private entity usually
considers effects on the area in which the majority of the entity's workers live and where most
of the businesses that depend on the entity are located.
There are no economic ratios per se that evaluate socioeconomic impacts. Instead, the
relative magnitudes of indicators such as increases in unemployment, losses to the local
economy, decreases in tax revenues, indirect effects on other businesses, decreases in water
supply alternatives, and increases in sewer fees for remaining private entities should be taken
into account when deciding whether impacts would prevent important development or could be
considered widespread and substantial. Since EPA does not have standardized tests and
benchmarks with which to measure these impacts, the following guidance is provided as an
example of the types of information that should be considered when reviewing impacts on the
surrounding community.
As important as the extent of the socioeconomic impacts are the types of impacts that
might occur. For a pubb'c entity, the effect of raising either taxes or user fees is to increase
household expenditures and thus reduce the desirability of the community from the perspective
of households and businesses. If businesses relocate due to their pollution reduction investments,
other tax revenues may decline. In an extreme case people may leave the area and other
3-22
-------
companies might be forced to close due to lack of business, thus further decreasing the economic
base of the community. Similarly, the closure of a private entity would cause unemployment,
with decreases in tax revenues and the local economic base and increased demand for
unemployment and social services; the overall impact would depend on the relative importance
in the community of the entity's employment. Where a water reclamation project is forced to
close or is not built, new sources of potable or process water must be developed, frequently at
a high cost. The provision of reclaimed water for existing manufacturing facilities would in
some cases free up potable water supplies for other purposes or permit communities to reduce
their purchases of potable water.
In certain circumstances, the information presented here may not adequately address all
potential impacts. State/dischargers should feel free to consider additional measures not
mentioned here if they judge them to be relevant Likewise, State/dischargers should not view
this guidance as a check list. State/dischargers should keep in mind that the public participation
in the UAA process will be an important way to identify potential socioeconomic impacts. More
detailed guidance on the factors that dischargers should consider when evaluating the
socioeconomic impacts to communities of meeting water quality standards in effluent-dependent
water bodies is given below. Further assistance on measuring socioeconomic impacts can found
in the draft Economic Guidance for Water Quality Standards available from the Office of Science
and Technology in the Office of Water at EPA Headquarters.
3.4.1 Measuring The Impact of Lost Water Reclamation Projects
As indicated in Region Dt's EDE Guidance, it may be appropriate to factor water
reclamation benefits into a UAA based on economic considerations. Whether privately- or
publicly-owned, the cost of pollution reduction technologies may make it difficult to build and
operate beneficial water reclamation projects. Such projects may result in valuable water
conservation benefits that would be foregone if the projects were not built. In this case, the
State/discharger may include the impact that elimination of a water reclamation project has on
3-23
-------
society in demonstrating widespread socioeconomic impacts. Guidance on how to address this
situation is given below.
Using the guidance outlined in Section 3.3 above, the analysis must show that the water
reclamation project (whether existing or proposed), would either shut down or not be built. The
State/discharger must also demonstrate that a market exists for its reclaimed water and that the
reclaimed water can be transported to a buyer. To estimate the resulting socioeconomic impacts,
the State/discharger should estimate the value of the water that would be saved or freed up for
other uses by the reclaimed water. The price of the next best alternative water supply, in the
absence of the water reclamation project should be used to estimate the value of the reclaimed
water that would be lost if the project was forced to close or not be built. Some examples of
next best alternative water supply include: a newly developed source, the town's current source
of water, or conservation activities implemented in the community to free up the additional water
supply.
The value of the lost reclaimed water must then be adjusted to account for the fact that
the community loses the benefit of cleaner water that would result from pollution reduction. In
other words, the value of the water saved must be offset by the cost of the pollution reduction
(a proxy for the benefits to the community of pollution reduction). In simple terms, the
State/discharger should use the following equation to estimate the impacts of forgoing a water
reclamation project:
Value of freed up water for other development
Cost of foregone pollution reduction (a proxy for the benefits of foregone
pollution reduction)
Total socioeconomic impact of lost water reclamation project
3-24
-------
To illustrate this situation, consider a municipality that might plan to build a water
reclamation project to reclaim 1.1 MGD3.from a source such as agricultural runoff or industrial
process water now discharged to a sewage treatment plant. The cost to the municipality of the
reclamation project is $7.3 million. The municipality will only build the reclamation project if
the benefit of the reclamation project (total value of the reclaimed water) is equal to or greater
than the cost of the project. The cost assumptions used in this example are listed in Table 3-2
below. The municipality claims, however, that it can only afford to build the water reclamation
project if it does not have to install pollution reductions to treat the reclamation project's effluent
(. 1 MGD) which would cost $2 million/year. If built, 1 MGD would be available to sell to
water users either in the same community or to users outside the community. For the purposes
of this example, assume that the municipality would sell all of the 1 MGD of the reclaimed
water for $.01/gallon to a manufacturer that was previously purchasing water from the
municipality at the same price. The municipality would end up with an additional 1 MGD that
could be used for additional development within the community.4 The impact of forgoing the
water reclamation project would, therefore, be estimated as the value of the 1 MGD that the
municipality was previously selling to the manufacturer. The dollar value of this water,
however, is not $.01 /gallon. Rather it must be estimated in terms of the marginal cost that the
municipality would have had to pay for the next best source of an additional 1 MGD of water
in the absence of the water reclamation project.5 Assuming the municipality's next best source
would cost them $.02/gallon for an additional 1 MGD, the benefit of the water reclamation
project would be $7.3 million/year ($.02/gallon x 365 days x 1,000,000 gallons). The benefit
of the reclamation project must be offset by the cost of the pollution reduction since the
municipality would have to forgo the benefit associated with the pollution reduction that the
'For this water reclamation project it is assumed that 1.1 MGD are treated, 1 MGD are reclaimed, and . 1 MGD
are discharged as effluent.
4In arid regions of the west, the presence of additional water supplies may create opportunities for development
that did not exist due to the lack of, or prohibitive price of, water.
3For this example it is assumed that alternative water supply sources are of higher quality and are more
expensive.
3-25
-------
Table 3-2
Water Reclamation Project Example
Cost Assumptions
Cost of Water Reclamation Project
Cost of Treating Reclamation Project Effluent
Price of Reclaimed Water
Price of Next Best Source of Water
$7.3 million
$2 million
$.01/gallon
$.02/gallon
3-26
-------
reclamation project did not undertake ($7,300,000 - $2,000,000 = $5,300,000/year). The total
value of the foregone project is, therefore, $5,300,000/year.
The State/discharger should keep in mind, however, that the demonstration of substantial
impacts associated with a lost water reclamation project is not, in and of itself, a demonstration
of widespread socioeconomic. impacts. The extent of the adverse impacts to the surrounding
community must also be evaluated and added to the impacts associated with the lost water
reclamation project. These impacts to the community are described in the next section.
3.4.2 Measuring Socioeconomic Impacts on Private and Public Entities
If the financial tests outlined in Section 3.3 above suggest that an entity or entities are
not able to afford necessary pollution reductions, then an additional analysis must be undertaken
by the entity to demonstrate that there will be widespread adverse effects on the surrounding
community. In this demonstration, the State/discharger must define the affected community (the
geographic area where project costs pass through to the local economy), consider the baseline
economic health of the community, and finally evaluate how the proposed project affects the
socioeconomic well-being of the community.
In the case of municipal pollution reduction projects, the affected community is most
often the immediate municipality. There are, however, a few exceptions where the affected
community includes individuals and areas outside the immediate community. On the one hand,
if business activity in the region is concentrated in a nearby community and not in the immediate
community, then the nearby community is also affected by loss of income in the immediate
community and should be included in the analysis. On the other hand, if business activity of
the region is concentrated in the immediate community, then outlying communities dependent
upon the immediate municipality for employment, goods, and services should also be included
in the analysis. Similarly, if a large number of workers commute to an industrial facility that
3-27
-------
is significantly affected by the' cost pass-through, then the affected community should include
the home communities of commuters as well as the immediate community.
The relevant ^geographic area for evaluating the socioeconomic effects of compliance by
private entities varies with each situation. For impacts from actions by a private entity, the area
typically is determined by the area in which the majority of its workers live and where most of
the businesses that depend on it are located. There are no simple rules for defining the relevant
area or community; the decision is based on the judgement of the State/discharger, subject to
EPA review.
The baseline analysis of the affected community(ies) should provide sufficient information
to determine the economic health of the community. A complete profile should include, at a
minimum, the following information for both the affected community(ies) and the State or region
»
in which the community is located:
percent of households below the poverty line;
median household income;
rate of industrial development;
economic health;
developing and declining industries; and
unemployment rate.
If available, other applicable information and studies of the local and regional economy should
be included. Each analysis should also provide a description of the economic well-being of the
community based on a summary of the quantitative measures described above. This information
provides the baseline for evaluating the likelihood of adverse socioeconomic impacts associated
with water pollution reductions. The role of the entity within the affected community should
also be considered when determining whether the affected community is able to absorb the
impacts of reduced business activity or closures. For example, if a private entity is a key
3-28
-------
contributor to the economic base of the affected community through property taxes and
employment, significant impacts could occur. Impacts may also be significant where the entity
is the primary producer of a particular product or service on which other nearby businesses or
the affected community depends. These two examples illustrate how the interdependence
between the entity and the affected community can be a major factor in demonstrating that the
impacts are not only substantial, but widespread.
For public entities, costs for pollution reduction projects (recovered through user fees,
pollutant surcharges, or taxes) result in less disposable income for households and higher
operating costs for industries in the affected community. How these changes in income and
profitability affect the local economy is the basis of the socioeconomic impact analysis.
Development of a model of the local economy is in most cases beyond the scope of analysis
expected by State/dischargers. Instead, a qualitative analysis of socioeconomic impacts is
usually sufficient. For example, if the threshold for costs as a fraction of median household
income is exceeded, it is important to determine how many households are below the poverty
line before the project and whether this number would increase after the project was completed.
Communities with very few low-income households are able to afford greater cost increases,
both in absolute and in percentage terms, than communities with a disproportionately large
number of low-income households.
Where pass-through of costs to industry results in plant or product-line closures, other
socioeconomic impacts may result. Some examples of these impacts include higher
unemployment, loss of wage income, and loss of State and local tax revenues.
For private entities, impacts on the affected community's economy result from the loss
of employment and a loss of local expenditures by the entity. It is possible, however, that the
loss of employment may be partially offset where the necessary pollution reduction requires the
construction and maintenance of additional pollution controls or treatment. If employees do
leave the area in search of opportunities, all of their income is lost to the community. If
employees stay in the area and are only able to find lower paying jobs or receive unemployment
3-29
-------
benefits, then the loss of income to the community would be equal to the difference between
existing and future income; the cost of unemployment benefits is calculated as a government
expense or an expense borne someplace else, whichever is appropriate to the situation.
Additional socioeconomic impacts associated with private entity compliance may include
effects on the local govemment(s), such as loss of property tax revenues. If the financial tests
suggest that a plant will shut down and the equipment and machinery will be sold, then the
assessed value of the property and tax revenues is lowered. In addition, local govemment(s)
may be faced with increased expenditures due to the shutdown of an entity or line. If
unemployment increases, the community may need additional or expanded social services. An
abandoned plant may require added police protection. If an entity is a large user of the local
water or sewer service then an entity or line closure will lead to lowered demand and possible
decreased efficiency for the particular services. For example, a water system may be designed
with a large industrial user in mind. If the user is eliminated the system may become expensive
for the remaining users since they have to pay a greater share of the fixed costs of the water or
sewer system.
Affected communities may also be faced with impaired development opportunities if the
need to comply with water quality standards discourages businesses from locating in the area in
*
the future, particularly where water suppb'es are scarce. If the affected entity has not yet been
built, additional expenditures on water pollution reductions may delay or cancel the entity's
construction. The loss of potential jobs and personal income to the community if the entity is
not built should, therefore, be assessed. In addition, the future losses in jobs, personal income
and tax revenues from other businesses that would chose not to locate in the affected community
should also be considered.
In some cases, impacts at the State level should be evaluated. The State may be faced
with two possible adverse impacts. The State may lose tax revenues from the lost production
and lost income if a private entity is closed. At the same time the State may encounter increased
expenditures for unemployment compensation and social services. It should be realized that
3-30
-------
impacts at the State level will typically be relatively minor. Only in the rare cases in which an
entity or.entities account for a significant portion of a State's total income will impacts be
important enough to be evaluated.
The loss of community income due to increased unemployment and reductions of local
expenditures by a private entity would increase as the money moves through the local economy.
Some portion of the lost income would have been spent in the local economy for the purchase
of other goods and services and thus other local employee salaries. They in turn would have
spent some portion of their income in the local economy. The multiplier effect of income in the
local economy means that each dollar lost to an employee results in the loss of more than one
dollar to the local economy. The value for the multiplier depends on such factors as the entity's
industry and how closed or open the local economy is. The U.S. Department of Commerce,
Bureau of Economic Analysis (BEA) has developed several multipliers to estimate the effect of
reduced economic activity on output (sales), earnings, and employment. These multipliers are
available by industry sector of 39 or 531 different industry classifications, depending on the level
of detail required. State/dischargers that are interested in using these multipliers are advised to
consult a copy of, RIMS II Regional Multipliers: A User Handbook of the Regional Input-Output
Modeling System from the National Technical Information Service (NTIS)6. Additional
information on using multipliers is available from the BEA.7
'The NTIS document number is #PB-86-230-216. Orders for the document can be placed by calling NTIS at
(703) 487-4650.
The BEA can be reached by calling (202) 523-0528 or -0594.
3-31
-------
3.4.3 Measuring Socioeconomic Impacts As Applied To More Than One Private
And/Or Public Entity
There are situations were more than one entity discharging to the same water body claims
economic hardship from the same water quality standard. For example, a proposed reclamation
project and a manufacturing facility might both argue that they could not afford to undertake the
pollution reduction that would be necessary for water quality standards to be met in the water
body. Similarly, several manufacturing facilities might argue that some of them would have to
shut down if forced to meet water quality standards while others would decide to divert their
wastewater to other uses or recycle their wastewater. The number of entities that could
potentially claim economic hardship is limited only by the number of current or proposed entities
discharging/potentially discharging to the water body. Regardless of the number of entities
claiming hardship, the financial impacts to each must be demonstrated separately, as outlined
above. The socioeconomic impacts to the community, however, should be evaluated together.
In other words, the cumulative impact on the community should be presented by
State/dischargers rather than the impacts associated with each of the entities.
3.5 Example Use Attainability Analysis based on Economic Considerations
In this section, an example of a UAA based on economic considerations is provided to
highlight the type of information and analysis that is required to demonstrate substantial and
widespread economic and social impacts. The information presented in this example, however,
should be viewed as a general illustration and not as a check list. Furthermore, this example
addresses a municipality's claim of substantial and widespread economic and social impacts. As
such, it does not address the types of information and analyses that would be required to
demonstrate substantial widespread economic and social impacts for a private entity. Finally,
it is important to keep in mind that every case is different and any unique situations of a case
should be included in the UAA. The potential economic and social impacts of meeting water
quality standards to the fictional city of Pleasantville, Arizona are described in this example.
3-32
-------
The city of Pleasantville operates the Pleasant Valley Treatment Plant which discharges
into the Pleasant River. A Class 1 aquatic life classification has been set for the segment of the
Pleasant Valley River directly adjacent to the Pleasant Valley Treatment Plant. The treatment
plant is in violation of this water quality standard based on the concentration of ammonia present
in their wastewater. Pleasantville is arguing that effluent limitations needed to meet a Class 1
aquatic life classification for the Pleasant River would be burdensome to the city. To meet the
water quality standards, Pleasantville would have to upgrade their existing secondary treatment
plant.
Given the city's financial condition, Pleasantville is contending that they cannot afford
to build and operate the additional treatment necessary to meet water quality standards. They
have conducted a UAA and submitted the results to the Arizona Department of Environmental
Quality (ADEQ) in an effort to demonstrate that meeting water quality standards would result
in substantial and widespread economic and social impacts. Pleasantville's first step was to
document that the designated use (Class 1 aquatic life classification) for the segment of the
Pleasant Valley River directly adjacent to the Pleasant Valley Treatment Plant is not the existing
use. The city made this demonstration by consulting Arizona's 305(b) reports dating back to
1975. Review of the 305(b) reports indicates that a Class 1 aquatic life classification has never
been obtained in that segment of the Pleasant Valley River.
The City of Pleasantville consulted with ADEQ and EPA frequently throughout the UAA
process. As a result of their contact with ADEQ and EPA, Pleasantville received valuable
ongoing guidance. A summary of the information submitted to the ADEQ is presented in Table
3-3. This information was also presented and discussed at a public hearing in Pleasantville.
In its submission, the city addresses the following five subjects:
The city's financial history;
Proof of the city's financial troubles;
3-33
-------
Table 3-3
Data Submitted to the Arizona Department
of Environmental Quality by the
City of Pleasantville, Arizona
Pleasantville's Financial History
Property Tax Revenues (1986)
Sales Tax and Miscellaneous Revenues (1986)
Total Tax Revenue (1986)
Government Revenues (FY 1991)
Market Value of Taxable Property (Current)
Operating Deficit (four out of last five years)
City Program and Service Cuts
Status of Capital Expenditures
Property Tax Delinquency Rate
= $13,042,000
= $8,301,000
= $21,343,000
- $16,500,000 (a decline of 23% since
1986)
= $753,382,000 (could be an overestimate
by as much as 40%)
= $100,000 (in FY 1991)
= Senior lunch program, police layoffs,
limited library hours
= Most capital expenditures suspended
indefinitely, with exception of a bridge
reconstruction fund
= 5.5% (up from 1% prior to 1986)
Pleasantville's Demographics
Population (1986)
Current Population (1991)
Type of household
moving away from Pleasantville
Number of Households
Median Household Income
Percent of Households Below the
Poverty Line
38,000 (up from 29,000 in 1980)
34,200 (decrease of 10% since 1986)
Single person households and smaller
two income families
12,100
$15,000
8 %
3-34
-------
Table 3-3 (Cont'd)
Data Submitted to the Arizona Department
of Environmental Quality by the
City of Pleasantville, Arizona
Geographical Location
Major Type of Employment
Regional Economic Conditions
Percentage of Total Wastewater Flow
Attributable to Residential
and Municipal Wastewater Flows
= Just outside Phoenix metropolitan area
= Industrial
= Recession
= 85%
Cost of Wastewater Treatment Upgrade
Capital Improvements
1985 dollars
1991 dollars
Annual Operating Costs
1985 dollars
1991 dollars
= $2,500,000
= $3,290,000 (using ENR cost index of
1.32)
= $750,000
= $802,000 (using ENR cost index of
1.07)
Financing for Wastewater Treatment Upgrade
Source of Financing
Repayment Term, Vehicle
Bond Rate
Annualized Capital Cost
Increased Operating Costs
= General obligation bond
= 20 years, property and sales tax
revenues
= 8.45% (optimistic), 11% (realistic)
= $346,400 (assuming 8.45% bond rate)
= $802,000 (assuming 8.45% bond rate)
3-35
-------
Table 3-3 (Cont'd)
Data Submitted to the Arizona Department
of Environmental Quality by the
City of Pleasantville, Arizona
Total Annual Cost of Upgrade
Total Annual Cost of Upgrade
= $1,148,400 (assuming 8.45% bond rate)
= $ 1,215,100 (assuming 11 % bond rate)
Impacts of Wastewater Treatment Upgrade of Pleasantville and the Users of the Wastewater
System
Annual Cost of the 1985 treatment
facility expansion
Total Annual Cost of Existing Plant
Plus Upgrade
Debt Service as a Percentage
of Annual Revenues
Debt Service as a Percentage
of Market Value of
Taxable Property
Household Burden
Total Wastewater Treatment Costs
as a Percentage of
Median Household Income
= $2,950,000
= $4,098,400 (assuming 8.45% bond rate)
= 24.8% (4,098,400/16,500,000)
= .54% (4,098,400/753,382,000)
= $288/year((4,098,400*.85)/12,100)
= 1.9
3-36
-------
The costs (capital, O&M, and annualized) of the necessary treatment upgrade;
Type of financing available for the capital portion of the treatment upgrade; and
Estimates of the impacts on the city and the users of the system.
Pleasantville 's Financial History and Current Standing
To characterize the city's financial history, Pleasantville has included the following
information:
Three years of audited financial statements for the city;
Debt repayment schedule for the past three years and future repayment schedule;
Demographics of the city;
Municipal statistics for the city; and
i
Five year Master Plan that includes planned capital expenditures.
Pleasantville collected this information from the city's annual report. Much of this
information is discussed in conjunction with other data the city has presented, as part of this
UAA.
In arguing that the city is having financial problems, the city has provided narrative
describing the fact that the city's revenues have fallen over the past three years because the
regional economy is losing jobs. Specifically, since 1986, Pleasantville has experienced a
decline in revenues due to a regional recession. In 1986, the city's tax revenues totaled
$21,343,000. Property tax revenues accounted for $13,042,000; sales tax and miscellaneous
revenues accounted for the remaining $8,301,000. Government revenues in fiscal year 1991
totaled $16,500,000, a decline of 23 percent since 1986. To balance the city budget during this
five year period, the city has eliminated many programs, such as the senior lunch program;
3-37
-------
reduced services, such as police layoffs and limited library hours. They have postponed most
capital expenditures indefinitely. The one exception in the later category is a bridge
reconstruction fund, deemed a vital transportation link to the city center. Even with these cuts
in expenditures, Pleasantville still had an operating deficit of $100,000 in FY91.
The revenue decline has resulted in an operating deficit in four of the last five years when
Pleasantville did not adequately anticipate the severity of the revenue shortfall. While the city
has attempted to accommodate changes in the local economy in the city's budget and spending
forecast, they do not see any way to fund a project such as a treatment plant upgrade.
Pleasantville1 s'changing demographics really highlight the city's situation. In 1986,
Pleasantville had a population of 38,000, up from 29,000 in 1980. Many residential and
commercial developments were begun during the period between 1980 and 1986. Most of the
new residents commuted to industrial jobs in the Phoenix metropolitan area. Since the peak in
1986, Pleasantville's population has declined by 10 percent as jobs were lost and people moved
out of the area. Of the remaining households, eight percent are below the poverty line.
Property foreclosures, both residential and commercial, are not uncommon. More importantly
for the municipality's financial standing is the fact that local sales tax revenues have declined
and the property tax delinquency rate has risen from less than 1 percent prior to 1986 to 5.5
percent last year.
Cost of the Treatment Upgrade
To meet water quality standards, Pleasantville has considered a number of different
pollution reduction alternatives. Each of these alternatives and associated costs was presented
to ADEQ in the UAA. Pleasantville concluded that the least expensive alternative that would
allow them to meet water quality standards was an upgrade of their secondary treatment plant.
Due to lack of resources, Pleasantville was not able to ask the city's engineering consulting firm
to provide them with a specific cost estimate for the treatment upgrade. When Pleasantville
3-38
-------
expanded their facility in 1985, however, preliminary costs estimates were made which would
achieve the required reductions in ammonia concentrations. In 1985 dollars, the incremental
costs were:
Capital Improvements: $2,500,000
Increased Annual Operating Costs: $750,000
These costs were converted to 1991 dollars using Engineering News Record (ENR) Cost Indices:
Capital Improvements: $3,290,000 (index=1.32)
Increased Annual Operating Costs: $802,000 (index=1.07)
After reviewing Pleasantville's assumptions about the type of treatment required and the cost of
that treatment, ADEQ verified that the treatment option chosen by the City was the most
appropriate, least cost option and that the estimated costs were accurate.
To finance the upgrade, Pleasantville assumed that the project would be financed through
a general obligation bond to be repaid over twenty years through property and sales tax
revenues. The capital costs were annualized over 20 years using a bond rate of 8.45 percent.
Similar financing and assumptions were used for the last major capital expenditure at the
treatment plant in 1985.
Annualized Capital Cost (principal + interest) = $346,400
+
Increased Operating Costs = S802.000
Total annual cost of upgrade = $1,148,400
Pleasantville feels that it is optimistic to think that they will be able to secure a bond
at this rate given the change in municipal finances that have occurred since they last issued a
bond. For comparison, they note that if an 11 percent interest rate is used, the total annual cost
of the upgrade would increase by 6 percent to $1,215,100.
3-39
-------
To evaluate the affordability of these c»sts and the impact of these costs to the
community, the following three measures are considered:
Annual debt service as a fraction of annual revenues;
Annual debt service as a fraction of market value of taxable property; and
Average annual wastewater treatment cost per household as a fraction of median
household income.
In addition to the proposed treatment upgrade, the annual cost of the 1985 treatment
facility expansion equals $2,950,000. Adding the upgrade project cost increase to the existing
treatment plant costs reflects the total burden of the treatment plant with improvements.
Pleasantville assumed a total annual treatment plant cost of $4,098,400 in their impact analysis.
Debt service as a percentage of annual revenues
Using the most recent year of revenue, the percentage is calculated as follows:
Debt service = $4.098.400 x 100 = 24.8 percent
Annual Revenues $16,500,000
The upgrade would mean that Pleasantville would be required to pay more than 20 percent of
their current revenues for the wastewater treatment.
Debt service as a percentage of market value of taxable property
Debt service = $4.098.400 x 100 = 0.41 percent
Market Value $ 1,005,760,000
of Taxable Property
3-40
-------
While this value is below the threshold value of .8 percent, it is important to note that
the latest market valuation study was completed in early 1987 when the real estate market was
expanding rapidly. Consequently, it does not reflect the very real decline in value for both
commercial and residential properties. According to the city assessor, the total value reported
above could overestimate the current value of taxable property by as much as 40 percent.
Household burden
Total annualized cost (residential^ $4.098.400 x .85 = S3.483.640
Number of households 12,100 12,100
= $288/household/yr
* 85 percent of the total cost is attributed to residential and municipal wastewater flows.
In 1991, the median household income for Pleasantville was $15,000. Wastewater
treatment costs represent 1.9 percent of the median household income. Given that many of the
single person households and the smaller two income families have relocated, the burden of this
debt will fall on those residents who remain; typically larger families with one full-time wage
earner and retirees on fixed incomes. In addition, of the households that remain, eight percent
are already below the poverty line. Another half a percent of households would be expected to
fall below the poverty line if Pleasantville undertakes additional wastewater treatment.
Pleasantville will allocate the remaining 15 percent of the cost among industrial users according
to wastewater flow. None of the local businesses in Pleasantville are expected to be adversely
affected by the increase in sewage costs.
In addition to presenting the adverse impacts of compliance with water quality
standards, Pleasantville acknowledges that there may be positive impacts in the form of the
creation of construction jobs. Specifically, workers will be hired to build the treatment upgrade,
thus reducing local unemployment and injecting disposable income into the local economy.
3-41
-------
Pleasantville estimates, however, that over the 4 years required to construct the treatment
upgrade, only 17 new full-time jobs will be created. Additionally, the City points out that they
cannot be sure that the construction firm that would be hired for the project would employ local
labor. Finally, once the upgrade was completed, the 17 construction jobs would be lost. As
a result, Pleasantville has concluded in their UAA that the additional jobs created by compliance
will have a negligible affect on the overall economic impact.
Results
Given the results of the affordability tests employed above and the additional
information presented by the city, the ADEQ has determined that Pleasantville cannot currently
afford the expenditures required to meet water quality standards. In addition, if Pleasantville
was forced to pay for the upgrade, widespread economic and social impacts would be felt in the
community. ADEQ added that they feel it is unlikely that additional users, residential or
commercial, will move to Pleasantville (thereby reducing the average cost per user).
Consequently, it seems improbable that the financial condition of the city of Pleasantville will
improve enough to make the required investments in the near future. The ADEQ based their
decision on the following specific points:
The financial health of the city is poor as evidenced by the fact that the city
reduced expenditures yet still had an operating deficit for four of the past five
years. The regional economy does not appear to offer much opportunity for
increases in sales or property taxes.
The city's debt to revenue ratio exceeds the threshold of 20 percent by a fair
amount.
Although the city's debt to property value ratio does not exceed the threshold of
.8 percent, it would if property values are overestimated by 32 percent or more.
The city assessor thinks that the overestimate may be as much as 40 percent.
The cost per household is in the grey area between 1 and 2 percent of median
household income. Above 2 percent there is almost certainly a significant impact.
3-42
-------
While the ratio is below the 2 percent threshold, there are indications that
Pleasantville's households are already experiencing hardships that this ratio does
not capture. For example, the percent of households below the poverty line even
before an increase in users fees is eight percent.
EPA Analysis of the Pleasantville UAA
After ADEQ made their decision, they passed the Pleasantville UAA on to EPA for
review and approval. EPA concurred with ADEQ's decision, pointing out the following
strengths in the analysis:
Pleasantville consulted with ADEQ throughout the process of conducting their
UAA.
Pleasantville identified all of their pollution reduction options and presented
estimates of the costs of each. Costs for each alternative were verified by both
ADEQ and EPA.
Pleasantville evaluated all three affordability measures recommended by EPA.
These measures were used as guidance and not as strict indicators of substantial
and widespread economic and social impacts. In one case the City was clearly
above the threshold. In the other two cases the City provided pertinent additional
information about local conditions that confirmed that the City would be adversely
affected by compliance costs.
EPA agrees with the assumptions made by PleasanrviUe including the interest rate
used and the use of a general obligation bond as a financing mechanism.
Pleasantville acknowledged that there could be some variability to their results due
to changing conditions in the community. As a result, high and low estimates for
variables they were uncertain of were used to evaluate some impacts. EPA agrees
that were there is some uncertainty, it is better to present the range of possible
impacts.
3-43
-------
3.6 Summary Of Financial Capability And Determination Of Whether Impacts Are
Substantial And Widespread
Using the guidance described above, the State/discharger must demonstrate that the
pollution reduction measures needed to meet water quality standards in the water body are not
affordable. In addition, the State/discharger must show that there will be widespread adverse
impacts to the community if it is required to meet the standards. Where entities are discharging
to effluent-dependent water bodies, the State/discharger may include the cost to society of the
loss of reclaimed water in their claim of substantial and widespread economic and social impacts.
Whether or not the State/discharger has successfully demonstrated that substantial and
widespread economic and social impacts would occur depends upon the EPA Regional
Administrator's review of the UAA.
If the EPA Regional Administrator determines that the State/discharger has not
demonstrated substantial and widespread economic and social impacts, the State/discharger must
either meet existing standards or may consider whether there are other physical, chemical, or
site-specific factors that preclude attainment of the designated use. These factors are discussed
in Chapters One and Two. Alternatively, if the State/discharger has demonstrated substantial
and widespread economic and social impacts, it does not have to meet the water quality standard
currently set for the water body.
Where several entities are discharging to the same water body and all of them are able
to demonstrate substantial and widespread economic and social impacts, the same guidance
applies. If, however, only some of the dischargers can prove substantial and widespread
economic and social impacts, the State should consider granting variances to dischargers
demonstrating hardship in the UAA while continuing to require the remaining dischargers to
comply with the standards. Variances arc valid for no more than three years but may be
renewed. In the interim, dischargers receiving variances will be expected to undertake some
additional pollution reduction, as described above. In this situation, the issuance of variances
is preferable to a removal of a designated use since other dischargers, who are capable of
meeting the standards, will still have to comply with the standards through their NPDES permits.
3-44
-------
References and Literature Cited
Adamus, P.R., L.T. Stockwell, Jr., E.J. Clairain, M.E. Morrow, L.P. Rozas, and R.D.
Smith. 1987a. Wetland evaluation technique (WET). Vol. I. Literature Review and
Evaluation Rationale. US Army Corps of Engineers. Waterways Experimental Station,
Vicksburg, MS.
Adamus, P.R,, E.J. Clairain, Jr., D.R. Smithe, and R.E. Young. 1987b, Wetland
evaluation technique (WET). Vol. n. Technical Report Y-87. US Army Corps of
Engineers. Waterways Experimental Station, Vicksburg, MS.
Anderson, B.W., R.W. Engel-Wilson, D.G. Wells, and R.D. Ohmart. 1977. Ecological
study of southwestern riparian habitats: techniques and data applicability, pp. 146-155. In:
Importance, Preservation and Management of Riparian Habitat: A Symposium. [Tucson,
Arizona, July 9, 1977] USDA Forest Service GTR-RM-43, Rocky Mountain Forest and
Range Experiment Station, Fort Collins, Colo. 217 pp.
Beanlands, G.E. and P.N. Dunker. 1983. An ecological framework for environmental
impact assessment in Canada. Dalhousie University Institute for Resource and
Environmental Studies and Federal Environmental Assessment Review Office. Halifax,
Nova Scotia.
Bilyard, G.R. 1987. The value of benthic infauna in marine pollution monitoring studies.
Mar. Poll. Bull. 18 : 581-585.
Bros, W.E. and B.C. Cowell. 1987. A technique for optimizing sample size (replication).
/. Expt. Mar. Biol. Ecol. 30 : 21-34.
Calliet, G.M., M.S. Love, and A.W. Ebeling. 1986. Fishes : A Field and Laboratory
Manual on their Structure, Identification, and Natural History. Belmont, CA : Wadsworth
Publishing. 194 pp.
Chesapeake Executive Council. 1988. Habitat requirements for Chesapeake Bay living
resources. Chesapeake Bay Program. Annapolis, MD.
Cohen,. 1977. Statistical Power Analysis for the Behavioral Sciences. New York, NY :
Academic Press.
Cox, D.R. and E.J. Snell. 1981. Applied Statistics, Principles and Examples. New York,
NY : Chapman and Hall.
Cuff, W. and N. Cpleman. 1979. Optimal survey design : Lessons from a stratified
random sample of macrobenthos. J. Fish. Res. Board Can. 36 : 351-361.
Day, J.W., C.A.S Hall, W.M. Kemp, and A. Yanez-Arancibia. 1989. Estuarine Ecology.
New York, NY : John Wiley and Sons. 558 pp.
-------
Draper, N.R. and H. Smith. 1981. Applied Regression Analysis. New York, NY : John
Wiley and Sons.
Elliot, J.M. 1971. Some methods for the statistical analysis of samples of benthic
invertebrates. Scientific Publication No. 25, Freshwater Biological Assn., Ferry House,
U.K. 148 pp.
Federal Interagency Committee for Wetland Delineation. 1989. Federal manual for
identifying and delineating jurisdictional wetlands. U.S. Army Corps of Engineers, U.S.
Environmental Protection Agency, U.S. Fish and Wildlife Service, and U.S.D.A. Soil
Conservation Service. Washington D.C.
Ferraro, S.P., F.A. Cole, W.A. DeBen, and R.C. Swartz. 1989. Power-cost efficiency
of eight macrobenthic sampling schemes in Puget Sound. Washington, USA. Can. J. fish.
Aquatic Sci. 46(10) : 2157-2165.
France, M.J. and P.D. Hedges. 1989. The appropriate use of remotely sensed satellite data
for water resource assessment and modeling, pp. 147-153. In : Remote Sensing for
Operational Applications. E.G. Barret and K.A. Brown, eds. Technical Contents of the 15*
annual conference of the Remote Sensing Society, September 1989. University of Bristol.
Fredette, T.J., D.A. Nelson, T. Miller-Way, J.A. Adair, V.A. Sotler, J.E. Clausner, E.B.
Hands, and F.J. Anders. 1989. Selected tools and techniques for physical and biological
monitoring of aquatic dredged material disposal sites. Final Report. U.S. Army Engineer
Waterways Experiment Station, Vicksburg, MS.
Gilbert, R.O. 1987. Statistical Methods for Environmental Pollution Monitoring. New
York, NY: Van Nostrand Reinhold Company.
Green, R.H. 1979. Sampling Design and Statistical Methods for Environmental Biologists.
New York, NY : John Wiley and Sons.
Hirsch, R.M. 1988. Statistical methods and sampling design for estimating step trends in
surface-water quality. Water Resource Bull. 24 : 493-503.
Johnson, R.R. and L.T. Haight. 1984. Riparian problems and initiatives in the american
southwest : A regional perspective, pp. 404-412. In : California Riparian Systems :
Ecology, Conservation, and Productive Management. R.E. Warner and K.M Hendrix, eds.
Berkeley, CA : University of California Press.
Johnson, R.A. and D.W. Wichern. 1982. Applied Multivariate Statistical Analyses.
Englewood Cliffs, NJ : Prentice-Hall, Inc.
Kolb, H. 1965. The Audubon winter bird-population study. Aud. Field Notes 19 : 432-
434.
-------
Lonard, R.I. and E. J. Clairain, Jr. 1986. Identification of methodologies for the assessment
of wetland functions and values. In : Proceedings: National Wetlands Assessment
Symposium. Assoc .of State Wetland Managers, Inc. Portland, ME. pp. 66-72.
Manly, B.F.J. 1986. Multivariate Statistical Methods: A Primer. New York, NY :
Chapman and Hall.
Mclntyre, A.D., J.M. Elliot, and D.V. Ellis. 1984. Introduction: design of sampling
programs. EBP Handbook No. 16. In: Methods for the Study of Marine Benthos. N.A.
Holme and A.D. Mclntyre, eds. Oxford : Blackwell Scientific Publications, pp. 1-26.
Meents, J.K., B.W. Anderson, and R.D. Ohmart. 1984. Sensitivity of riparian birds to
habitat loss. pp. 619-625. In: California Riparian Systems: Ecology, Conservation, and
Productive Management. R.E. Warner and K.M. Hendrix, eds. University of California
Press, Berkeley, CA. 1035 pp.
Millard, S.P. and D.P. Lettenmaier. 1986. Optimal design of biological sampling programs
using the analysis of variance. Est. CstL Shelf ScL 22 : 637-656.
Omernik, J.M. 1987. Ecoregions of the conterminous United States. Annals Assoc. of Am.
Geographers 77 : 118-125.
Price, D.G. 1982. A fishery resource sampling methodology for small streams. Pacific
Gas and Electric report 420-81.141.
Schemnitz, S.D. 1980. Wildlife management techniques manual. Fourth edition. The
Wildlife Society, Bethesda, MD. 686 pp.
SCS. 1976. National range handbook. U.S.D.A Soil Conservation Service.
Seal, 1964. Multivariate Statistical Analysis for Biologists.
Segar, D.A. and E. Stamman. 1986. Fundamentals of marine pollution monitoring
programme design. Mar. Poll. Bull. 17(5): 194-200.
Sokal, R.R. and F.J. Rohlf. 1981. Biometry. San Francisco, CA : W.H. Freeman and
Company.
Svensson, S. 1970. An international standard for a mapping method in bird census work
recommended by the International Bird Census Committee. Aud. Field Notes 24 : 722-726.
US FWS. 1980. Habitat evaluation procedures (HEP) manual. US Department of the
Interior. Washington, D.C.
-------
US EPA. 1983a. Technical support manual : Water-body surveys and assessments for
conducting use attainability analyses. US Environmental Protection Agency. Washington,
D.C. ...
US EPA. 1983b. Water quality standards handbook. US Environmental Protection
Agency. Washington, D.C.
U.S. EPA. 1985. Recommended biological indices for 301(h) monitoring programs. EPA
430/9-86-002. Office of Marine and Estuarine Protection, Washington DC. 34 pp.
US EPA. 1986a. Handbook : Stream sampling for wasteload allocation applications. US
Environmental Protection Agency. Washington, D.C.
US EPA. 1986b. Test methods for evaluating solid wastes, physical/chemical methods.
SW-846, 3rd. edition. US Environmental Protection Agency. Washington, D.C.
US EPA. 1989. Rapid bioassessment protocols for use in streams and rivers : Benthic
macroinvertebrates and fish. US Environmental Protection Agency. Washington, D.C.
US EPA. 1990a. Office of Water environmental and program information systems
compendium. EPA 500/9-91-002. US Environmental Protection Agency. Washington, D.C.
US EPA. 1990b. Biological criteria : National program guidance for surface waters. US
Environmental Protection Agency. Washington, D.C.
US EPA. 199la. Guidance for modifying water quality standards and protecting effluent-
dependent ecosystems. Draft. Region 9, US Environmental Protection Agency. San
Francisco, CA.
US EPA. 1991b. Monitoring guidance for the National Estuary Program. Interim Final.
EPA 503/8-91-002. US Environmental Protection Agency. Washington, D.C.
US EPA. 1992a. Guidance for modifying water quality standards and protecting effluent-
dependent ecosystems. US Environmental Protection Agency, Region 9. San Francisco,
CA.
US EPA. 1992b. Guidance for modifying water quality standards and protecting effluent-
dependent ecosystems. Interim Final. US Environmental Protection Agency. Washington,
D.C.
US EPA. 1992c. Technical characterization guidance for the National Estuary Program.
Draft. US Environmental Protection Agency. Washington, D.C.
US EPA. 1992d. Compendium of watershed-scale models for TMDL development. EPA
841-R-92-002. US Environmental Protection Agency. Washington, D.C.
-------
Van Velzen, W.T. 1972. Breeding-bird census instructions. Am. Birds 26 : 1007-1010.
Zar, J.H. 1974. Biostatistical Analysis. Englewood Cliffs, NJ : Prentice-Hall, Inc.
-------
APPENDIX A
INFORMATION ON THREATENED /ENDANGERED SPECIES
-------
INFORMATION ON THREATENED AND ENDANGERED SPECIES
REFERENCES
Rutman, Sue/U.S. Fish and Wildlife Service. Summer 1992. "Handbook of Arizona's
Endangered, Threatened, and Candidate Plants"
Department of Fish and Game/New Mexico. 1977. "Handbook of Species Endangered in
New Mexico"
Sivinski, Robert and Lightfoot, Karen. March 1992. "Inventory of Rare and Endangered
Plants of New Mexico"
Department of Fish and Game/The Resources Agency. July 1992. "Endangered and
Threatened Animals of California"
Department of Fish and Game/Natural Heritage Division. January 1992. "Designated
Endangered, Threatened or Rare Plants and Candidates with Official Listing Dates"
Department of Interior/U.S. Fish and Wildlife Service. July 1991. "Endangered and
Threatened Wildlife and Plants"
Arizona Game and Fish Department. July 1988. "Threatened Native Wildlife in Arizona"
Morefield, James D. and Knight, Teri A. December 1991. "Endangered, Threatened, and
Sensitive Vascular Plants of Nevada"
LIST OF CONTACTS
Arizona
Arizona Game and Fish Department
Nongame Branch
Phoenix, AZ
602/789-3500
(For Mammals, Birds, Fish, Reptiles and Amphibians)
Agriculture and Horticulture Department of Arizona
Tucson, Arizona
602/628-5396
(For Plants)
-------
California
Natural Heritage Federation - CA
Sacramento, CA
916/322-2493
(For Everything.- State Listed)
Nevada
Natural Heritage Program - Nevada
Carson City, NV
702/687-4245 .
(For Everything - State Listed)
-------
Key to Threatened and Endangered Species Tables*
FE = Federally Listed Endangered Species
FT = Federally Listed Threatened Species
SE = State Listed Endangered Species
ST = State Listed Threatened Species
'Priority was given .to the federal status of species. Species on the tables identified as state
listed were not included on federal listings.
-------
Threatened and Endangered Species in Nevada
Scientific Name
FISH
Catostomus wamerensis
Chasmlstes cujus
Crenlchthys bailey! bailey!
Crenlchthys balleyi grandis
Crenlchthys nevadae
Cyprinodon diabolis
Cyprinodon nevadensls mionectes
Cyprinodon nevadensis pectoralis
Empetrichthys latos
Eremichthys acros
Gila cypha
Gila elegans
Gila robusta Jordan!
Gila robusta seminuda
Lepidomeda albivallis
Lepidomeda mollispinis pratensis
Moapa coriacea
Oncorhynchus dark! henshawi
Oncorhynchus tshawytscha
Plagopterus argentissimus
Ptychocheilus lucius
Rhinichthys osculus lethoporus
Rhinichthys osculus nevadensis
Rhinichthys osculus oligoporus
Xyrauchen texanus
BIRDS
Falco peregrinus
Gymnogyps califomlanus
Haliaeetus leucocephalus
Mycteria americana
Pelecanus occidentalis
Sterna antillarum
MAMMALS
Common Name Status
Warner sucker FT
Cui-ui FE
White River springfish FE
Hiko White River springfish FE
Railroad Valley springfish FT
Devil's Hole pupfish . FE
Ash Meadows Amargosa pupfish FE
Warm Springs Amargosa pupfish FE
Pahrump killifish FE
Desert dace FT
Humpback chub* FE
Bonytail chub FE
Pahranagat roundtail chub FE
Virgin River chub FE
White River spinedace FE
Big Spring dace FT
Moapa dace FE
Lahontan cutthroat trout FT
Chinook salmon FT
Woundfin FE
Colorado squawfish* FE
I ndependence Valley speckled dace FE
Nevada speckled dace FE
Clover Valley speckled dace FE
Razorback sucker FE
Peregrine falcon FE
California condor FE
Bald eagle FE
Wood stork FE
Brown pelican FE
Least tern FE
Can/s lupus
Gray wolf*
FE
-------
REPTILES
Copherus agassizii
PLANTS
Arabls rigidissima var. demota
Arctomecon califomica
Astragalus beatleyae
Astragalus geyeri var. triquetrus
Astragalus mohavensis var. hemigyrus
Astragalus phoenix
Astragalus yoder-williamsii
Castllleja salsuglnosa
Centaurtum namophllum
Cryptantha Insollta
Enceliopsls nudicaulis var. corrugata
Eriogonum argophyllum
Eriogonum ovalifolium var. williamsiae
Eriogonum viscidulum
Frasera gypsicola
Grindelia franxino-pratensis
Ivesia kingii var. eremica
Mentzella leucophylla
Nitrophila mohavensis
Opuntia whippleivar. multigeniculata
Phacelia Inconspicua
Polyctenium williamsiae
Primula capillaris
Horippa subumbellata
Sclerocactus blainei
Sclerocactus schlesseri
Spiranthes diluvialis
Desert tortoise
Galena Creek rockcress
California bearpoppy
Beatley milkvetch
Threecorner milkvetch
Halfring milkvetch
Ash Meadows milkvetch
Osgood Mountains milkvetch
Monte Neva paintbrush
Spring-loving centaury
Unusual catseye
Ash Meadows sunray
Sulphur Springs buckwheat
Steamboat buckwheat
Sticky buckwheat
Sunnyside green gentian
Ash Meadows gumplant
Ash Meadows ivesia
Ash Meadows blazingstar
Amargosa niterwort
Blue diamond cholla
Obscure scorpion plant
Williams combleaf
Ruby Mountain primrose
Tahoe yellowcress
Elaine pincushion
Schlesser pincushion
Utes ladies' tresses
FT
SE
SE
SE
SE
SE
FT
SE
SE
FT
SE
FT
SE
FE
SE
SE
FT
FT
FT
FE
SE
SE
SE
SE
SE
SE
SE
FT
Not thought to be present in Nevada.
-------
Threatened and Endangered Species in Arizona
Scientific Name
FISH
Campostoma ornatum price!
Catostomus bernardini
Cyprinodon macularius
Gila cypha
Glla ditaenla
Gila elegans
Gila Intermedia
Gila purpurea
Gila robusta robusta
Gila robusta seminuda
Jctalurus price!
Lepidomeda mollispinis mollispinis
Lepidomeda vittata
Meda fulgida
Notropis formosus
Oncorhynchus apache
Oncorhynchus gilae
Plagopterus argentissimus
Poeclliopsis occidentals occldentalis
Poeclliopsis occldentalis sonoriensis
Ptychocheilus luclus
Tiaroga cobitis
Xyrauchen texanus
BIRDS
Ammodramus balrdi!
Buteo nltidus
Buteo regalis
Casmerodius albus
Catharus fuscescens
Coccyzus amerlcanus
Collnus vlrginlanus rldgwayi
Dolichonyx oryzlvorus
Dumetella carolinensls
Egretta thula
Empldonax fulvlfrons
Empldonax tralllil
Falco femoralis septentrlonalis
Common Name
Arizona stoneroller
Yaqui sucker
Desert pupfish
Humpback chub
Sonora chub
Bonytail chub
Gila chub
Yaqui chub
Colorado roundtail chub
Virgin River chub
Yaqui catfish
Virgin spinedace
Little Colorado spinedace
Spikedace
Beautiful shiner
Arizona trout
Gila trout
Woundfin
Gila topminnow
Yaqui topminnow
Colorado squawfish
Loach minnow
Razorback sucker
Baird's sparrow
Gray hawk
Ferruginous hawk
Great egret
Veery
Yellow-billed cuckoo
Masked bobwhite
Bobolink
Gray catbird
Snowy egret
Buff-breasted flycatcher
Willow flycatcher
Northern Aplomado falcon
Status
SE
SE
FE
FE
FT
FE
ST
FE
ST
FE
FT
SE
FT
FT
FT
FT
FE
FE
FE
FE
FE
FT
FE
ST
ST
ST
SE
ST
ST
FE
SE
ST
ST
SE
SE
FE
-------
Falco peregrinus
Glaucidium brasilianum
Grus americana
Gymnogyps califomianus
Haliaeetus leucocephalus
Laterallus jamaicensis
Pandion haliaetus
Rallus longirrostris yumanensls
Rhynchopsitta pachyrhyncha
Setophaga ruticllla
Strix occidentalis
MAMMALS
Antilocapra americana mexicana
Antilocapra americana sonoriensis
Canis lupus baileyi
Choeronycteris mexicana
Cynomys ludovlclanus
Dipodomys spectabilis baileyi
Fells concolor brown!
Fells onca
Fells pardalis
Leptonycteris sanborni
Lutra canadensis sonora
Microtus mexicanus hualpaiensis
Microtus mexicanus navaho
Mustela nigropes
Sorex palustris
Tamiasclurus hudsonicus grahamensis
Ursus arctos
Zapus hudsonius
REPTILES
Eumeces gilbert! arizonensls
Phrynosoma mcallii
Sistrurus catenatus
AMPHIBIANS
Ambystoma tigrlnum stebbinsl
Hylactophryne august!
Rana blalrl
Rana chlricahuensls
Rana tarahumarae
Peregrine falcon FE
Ferruginous pygmy-owl SE
Whooping crane FE
California condor FE
Bald eagle FE
Black rail SE
Osprey ST
Yuma clapper rail FE
Thick-billed parrot "SE
American redstart ST
Spotted owl ST
Chihuahuan pronghorn antelope ST
Sonoran pronghorn antelope FE
Mexican gray wolf FE
Mexican long-tongued bat ST
Black-tailed prairie dog SE
New Mexican banner-tailed kangaroo rat SE
Yuma puma SE
Jaguar SE
Ocelot FE
Sanborn's long-nosed bat FE
Southwestern river otter SE
Hualapai Mexican vole FE
Navajo Mexican vole ST
Black-footed ferret FE
Water shrew SE
Mount Graham red squirrel FE
Grizzly bear FT
Meadow jumping mouse ST
Arizona skink SE
Flat-tailed horned lizard ST
Massasauga rattlesnake SE
Huachuca tiger salamander SE
Barking frog SE
Plains leopard frog SE
Chiricahua leopard frog ST
Tarahumara frog SE
-------
PLANTS
Agave arizonica
Amsonia kearneyana
Asclepias welshii
Astragalus cremnophylax var. cremnophylax
Carex speculcola
Coryphantha robbinsorum
Coryphantha scheeri var. robustipina
Cycladenia humllis var. jonesii
Echlnocactus hortzonthalonius var. nlcholii
Echlnocereus trlglochldlatus var. arlzonicus
Pediocactus bradyl
Pedlocactus peebleslanus var. peebleslanus
Pediocactus sllerl
Purshla sublntegra
Senecio franciscanus
Turnamoca macdougalii
Arizona agave
Kearney blue star
Welsh's milkweed
Sentry milk vetch
Navajo sedge
Cochise pincushion cactus
Pima pineapple cactus
Jones' cycladenia
Nichol Turk's head cactus
Arizona hedgehog cactus
Brady pincushion cactus
Peebles Navajo cactus
Siler pincushion cactus
Arizona cliffrose
San Francisco Peaks groundsel
Tumamoc globeberry
FE
FE
FT
FE
FT
FT
*FT
FT
FE
FE
FE
FE
FE
FE
FT
FE
-------
Threatened and Endangered Species in California
Scientific Name
FISH
Catostomus microps
Chasmlstes brevirostris
Cottus asperrlmus
,. Cyprinodon macularius
Cyprinodon radiosus
Cyprinodon salinus mllleri
Deltistes luxatus
Gasterosteus aculeatus Williamson!
Gila bicolor mohavensis
Gila bicolor snyderi
Gila eiegans
Oncorhynchus aguabonita white!
Oncorhynchus dark! henshawi
Oncorhynchus clarki seleniris
Oncorhynchus tshawytscha
Ptychocheilus lucius
Salvelinus confluentus
Xyrauchen texanus
BIRDS
Amphispiza belli clementeae
Brachyramphus marmoratus
Branta canadensis leucopareia
Buteo swalnsoni
Coccyzus americanus occidentalis
Colaptes auratus chrysoides
Empidonax traillii
Falco peregrinus anatum
Grus canadensis tablda
Gymnogyps califomianus
Haliaeetus leucocephalus
Lanius ludovlclanus mearnsl
Laterallus jamalcensls cotunlculus
Melanerpes uropygialis
Micrathene whitneyl
Passerculus sandwichensis beldingi
Pelecanus occidentalis califomicus
Pipilo fuscus eremophilus
Common Name
Modoc sucker
Shortnose sucker
Rough sculpin
Desert pupfish
Owens pupfish
Cottonball Marsh pupfish
Lost River sucker
Unarmored threespine stickleback
Mahave tui chub
Owens tui chub
Bonytail chub
Little Kern golden trout
Lahontan cutthroat trout
Paiute cutthroat trout
Winter-run Chinook salmon
Colorado squawfish
Bull trout
Razorback sucker
San Clemente sage sparrow
Marbled murrelet
Aleutian Canada goose
Swainson's hawk
Western yellow-billed cuckoo
Gilded Northern flicker
Willow flycatcher
American Peregrine falcon
Greater Sandhill crane
California condor
Bald eagle
San Clemente loggerhead shrike
California black rail
Gila woodpecker
Elf owl
Belding's Savannah sparrow
California brown pelican
Inyo brown towhee
Status
FE
FE
ST
FE
FE
ST
FE
FE
FE
FE
FE
FT
FT
FT
FT
FE
SE
FE
FT
SE
FT
ST
SE
SE
SE
FE
ST
FE
FE
FE
ST
SE
SE
SE
FE
FT
-------
Rallus longirostris levipes
Rallus longirostris obsoletus
Rallus longirostris yumanensis
Riparia riparia
Sterna antillarum brown!
Strix nebulosa
Strix occidentals caurina
Vireo belli! arizonae
Vireo belli! pusillus
MAMMALS
Ammospermophilus nelson!
Aplodontia rufa nigra
Arctocephalus townsendi
Balaena glaclalis
Balaenoptera borealis
Balaenoptera musculus
Balaenoptera physalus
Dipodomys heermanni morroensis
Dipodomys Ingens
Dipodomys nitratoides exilis
Dipodomys nitratoides nitratoides
Dipodomys Stephens!
Enhydra lutris nereis
Eschrichtius robustus
Eumetoplas jubatus
Gulo gulo
Megaptera novaeangliae
Microtus californicus scirpensls
CMs canadensls californiana
CMs canadensis cremnobates
Physeter catodon
Relthrodontomys raviventrls
Spermophllus mohavensis
Urocyon littoralis
Vulpes macrotls mutlca
Vulpes vulpes necator.
REPTILES
Caretta caretta
Charina bottae umbratica
Chelonla mydas
Coleonyx switak!
Dermochelys corlacea
Gambelia sllus
Light-footed clapper rail
California clapper rail
Yuma clapper rail
Bank swallow
California least tern
Great gray owl
Northern spotted owl
Arizona Bell's vireo
Least Bell's vireo
San Joaquin antelope squirrel
Point Arena Mountain beaver
Guadalupe fur seal
Right whale
Set whale
Blue whale
Rnback whale
Morro Bay kangaroo rat
Giant kangaroo rat
Fresno kangaroo rat
Tipton kangaroo rat
Stephens' kangaroo rat
Southern sea otter
Gray whale
Northern (Steller) sea lion
Wolverine
Humpback whale
Amargosa vole
California bighorn sheep
Penninsular bighorn sheep
Sperm whale
Salt-marsh harvest mouse
Mohave ground squirrel
Island fox
San Joaquin kit fox
Sierra Nevada red fox
Loggerhead sea turtle
Southern rubber boa
Green sea turtle
Barefoot banded gecko
Leatherback sea turtle
Blunt-nosed leopard lizard
FE
FE
FE
ST
FE
SE
FT
SE
FE
ST
FE
FT
FE
FE
FE
FE
FE
FE
FE
FE
FE
FT
FE
FT
ST
FE
FE
ST
ST
FE
FE
ST
ST
FE
ST
FT
FT
FT
FT
FE
ST
-------
Gopherus agassizii
Lepidochelys olivacea
Masticophis lateralis euryxanthus
Thamnophis couchii gigas
Thamnophis sirtalis tetrataenia
Uma Inornata
Xantusla riversiana
AMPHIBIANS
Ambystoma macrodactylum croceum
Batrachoseps aridus
Batrachoseps slmatus
Batrachoseps stebbinsi
Bufo exsul
Hydromantes brunus
Hydromantes shastae
Plethodon stormi
PLANTS
Acatnhomintha Hicifolia
Acatnhomintha obovata ssp. duttonii
Allium fimbriatum var. munzii
Amsinckia grandiflora
Arabis macdonaldiana
Arctostaphylos denslflora
Arctostaphylos hooker! ssp. hearstiorum
Arctostaphylos hooker! ssp. ravenii
Arctostaphylos imbricata
Arctostaphylos pacifica
Arctostaphylos pallida
Arenarla paludicola
Astragalus agnlcidus
Astragalus clarianus
Astragalus lentiglnosus var. sesquimetralis
Astragalus magdalenae var. peirsonli
Astragalus tener var. tlti
Atrlplex tularensis
Blennosperma baker!
Brodiaea coronarla ssp. rosea
Brodiaea filifolia
Brodiaea Insignls
Brodiaea pallida
Calochortus tiburonensis
Calystegia stebblnsli
Carexalblda
Desert tortoise
Olive Ridley sea turtle
Alameda whipsnake
Giant garter snake
San Francisco garter snake
Coachella Valley fringe-toed lizard
Island night lizard
Santa Cruz long-toed salamander
Desert slender salamander
Kern Canyon slender salamander
Tehachapi slender salamander
Black toad
Limestone salamander
Shasta salamander
Siskiyou Mountains salamander
San Diego thorn mint
San Mateo thorn mint
Munz's onion
Large-flowered fiddleneck
McDonald's rock cress
Vine Hill manzanita
Hearst's manzanita
Presidio manzanita
San Bruno Mountain manzanita
Pacific manzanita
Alameda manzanita
Marsh sandwort
Humboldt milk vetch
Clara Hunt's milk vetch
Sodaville milk vetch
Peirson's milk vetch
Coastal Dunes milk vetch
Bakersfield saltbrush
Sonoma sunshine
Indian Valley brodiaea
Thread-leaved brodiaea
Kaweah brodiaea
Chinese Camp brodiaea
Tiburon mariposa lily
Stebbins' morning-glory
White sedge
FT
FE
FT
ST
ST
.FE
ST
FE
FE
ST
ST
ST
ST
ST
ST
SE
FE
ST
FE
FE
SE
SE
FE
SE
SE
SE
SE
SE
ST
SE
SE
SE
SE
FE
SE
SE
SE
SE
ST
SE
SE
-------
Carpentaria californica
Castilleja grisea
Castilleja neglecta
Castilleja uliginosa
Caulanthus californicus
Centrostegia leptoceras
Cercocarpus traskiae
Chorlzanthe howellii
Chorlzanthe orcuttiana
Chorizanthe valida
Cirslum dliolatum
Cirslum fontlnale var. fontinale
Cirslum loncholepis
Cirsium rhothophilum
Clarkla franciscana
Clarkia Imbricata
Clarkia lingulata
Clarkia springvillensls
Cordylanthus maritimus ssp. maritimus
Cordylanthus palmatus
Cordylanthus rigidus ssp. littoralis
Cupressus abramsiana
Delphinium kinkiense
Dichanthelium lanuginosum var. thermale
Dithyrea maritima
Downingia concolor var. brevior
Dudleya brevifolia
Dudleya stolonifera
Dudleya traskiae
Eriastrum densifolium ssp. sanctorum
Eriodictyon altisslmum
Eriogonum alpinum
Eriogonum apricum var. apricum
Eriogonum apricum var. prostratum
Eriogonum ericlfollum var. thomel
Eriogonum grande ssp. timorum
Eriogonum kelloggll
Erynglum aristulatum var. parishil
Eryngium constancel
Erynglum racemosum
Eryslmum capltatum var. angustatum
Erysimum menziesli
Eryslmum teretlfollum
Fritillarla roderickil
Fritillaria striata
Galium catalinense ssp. acrispum
Gilia tenuiflora ssp. arenaria
Gratiola heterosepala
Tree-anemone ST
San Clemente Island Indian paintbrush FE
Tiburon Indian paintbrush ST
Pitkin Marsh Indian paintbrush SE
California jewelflower FE
Slender-horned spineflower FE
Santa Catalina Island mountain-mahogany SE
HowelPs spineflower ST
Orcutt's spineflower SE
Sonoma spineflower SE
Ashland thistle SE
Fountain thistle SE
La Graciosa thistle ST
Surf thistle ST
Presidio Clarkia SE
Vine Hill Clarkia SE
Merced clarkia SE
Springville clarkia SE
Salt marsh bird's-beak FE
Ferris' bird's-beak FE
Seaside bird's-beak SE
Santa Cruz cypress FE
San Clemente Island larkspur FE
Geyser's panfcum SE
Beach spectacle pod ST
Cuyamaca Lake downingia SE
Short-leaved dudleya SE
Laguna Beach dudleya ST
Santa Barbara Island dudleya FE
Santa Ana River woollystar FE
Indian Knob mountainbalm SE
Trinity buckwheat SE
lone buckwheat SE
Irish Hill buckwheat SE
Thome's buckwheat SE
San Nicholas Island buckwheat SE
Kellogg's buckwheat SE
San Diego button celery SE
Loch Lomond button celery FE
Delta button celery SE
Contra Costa wallflower FE
Menzies1 wallflower SE
Santa Cruz wallflower SE
Roderick's fritillary SE
Striped adobe lily ST
San Clemente Island bedstraw SE
Sand gilia ST
Boggs Lake hedge-hyssop SE
-------
Helianthus niveus ssp. tephrodes
Hemizonia conjugens
Hemlzonia increscens ssp. villosa
Hemizonia mohavensis
Heasperolinon didymocarpum
Holocarpha macradenia
Lasthenia burkei
Layia carnosa
Lesslngia germanorum
Ulium occidental
Ulium pitkinense
Umnanthes douglasli var. sulphurea
Llmnanthes floccosa ssp.californica
Umnanthes gracilis var. parishii
Umnanthes vlnculans
Llthophragma maximum
Lotus agrophyllus ssp. adsurgens
Lotus agrophyllus ssp. niveus
Lotus dendroldeus var. traskiae
Lupinus deflexus
Lupinus milo-bakeri
Lupinus nipomensis
Lupinus tidestromii var tidestromii
Mahonia nevinii
Mahonia pinnata ssp. insularis
Mahonia sonnei
Malacothamnus clementinus
Malacothamnus fasciculatus var. nesioticus
Monardella linoides ssp. viminea
Navarretia pauciflora
Navarretia plieantha
Neostapfia colusana
Nitrophlla mohavensis
Nolina Interrata
Oenothera avita ssp. eurekensis
Oenothera deltoides ssp. howellii
Opuntia basilaris var. treleasei
Orcuttia califomlca
Orcuttia Inaequalis
Orcuttia pilosa
Orcuttia tenuis
Orcuttia viscida
Orthocarpus campestris var. succulentus
Parvisedum leiocarpum
Pentachaeta bellidiflora
Pentachaeta /yon/7
Phlox hirsuta
Plagiobothrys diffusus
Algodones Dunes flower
Otay tarplant
...Gaviotatarplant
Mohave tarplant
Lake County dwarf flax
Santa Cruz tarplant
Burke's goldfields
Beach layia
San Francisco lessingia
Western Illy
Pitkin Marsh lily
Point Reyes meadowfoam
Butte County meadowfoam
Parish's meadowfoam
Sebastopol meadowfoam
San Clemente Island woodland star
San Clemente Island bird's-foot trefoil
Santa Cruz Island bird's-foot trefoil
San Clemente Island lotus
Mariposa lupine
Milo Baker's lupine
Nipomo Mesa lupine
Tidestrom's lupine
Kevin's barberry
Island barberry
Truckee barberry
San Clemente Island bush mallow
Santa Cruz Island bush mallow
Willowy monardella
Few-flowered navarretia
Many-flowered navarretia
Colusa grass
Amargosa nitrophila
Dehesa nolina
Eureka Dunes evening-primrose
Antioch Dunes evening-primrose
Bakersfield cactus
California Orcutt grass
San Joaquin Valley Orcutt grass
Hairy Orcutt grass
Slender Orcutt grass
Sacramento Orcutt grass
Succulent owl's-clover
Lake County stonecrop
White-rayed pentachaeta
Lyon's pentachaeta
Yreka phlox
San Francisco popcornflower
SE
SE
SE
SE
SE
SE
FE
SE
-SE
SE
SE
SE
SE
SE
FE
SE
SE
SE
FE
ST
ST
SE
SE
SE
SE
FE
FE
SE
SE
ST
SE
ST
FE
SE
FE
FE
FE
SE
SE
SE
SE
SE
SE
SE
SE
SE
SE
-------
Plagiobothrys strictus Calistoga popcornflower ST
Poanapensis Napa blue grass SE
Pogogyne abramsii San Diego mesa mint FE
Pogogyne clareana Santa Lucia mint SE
Pogogyne nudiuscula Otay mesa mint SE
Potentilla hickmanii Hickman's cinquefoil SE
Pseudobahla bahlifolia Hartweg's pseudobahia SE
Pseudobahia pelrsonli Tulare pseudobahia SE
Rorippa gambellii Gambel's watercress "ST
Rorlppa subumbellata Tahoe yellow cress SE
Rosa mlnutifolia Small-leaved rose SE
Sidalcea covlllel Owens Valley checkerbloom SE
Sldatcea oregana ssp. valida Kenwood Marsh checkerbloom SE
Sidalcea pedata . Bird-footed checkerbloom FE
Sidalcea stipularls Scadden Flat checkerbloom SE
Sllene campanulata ssp. campanulata Red Mountain catchfly SE
Streptanthus nlger Tiburon jewelflower SE
Swallenla alexandrae Eureka Valley dune grass FE
Thelypodium stenopetalum Slender-petaled thelypodium FE
Trifolium trichocalyx Monterey clover ' SE
Tuctoria mucronata Crampton's tuctoria FE
Verbesina dissita Big-leaved crown-beard ST
-------
References
Arizona Game and Fish Department. July 1988. "Threatened Native Wildlife in Arizona."
Calfornia Department of Fish and Game/Natural Heritage Division. January 1992. "Designated
Endangered, Threatened or Rare Plants and Candidates with Official Listing Dates."
California Department of Fish and Game/The Resources Agency. July 1992. "Endangered and
Threatened Animals of California."
Morefield, James D. and Knight, Teri A, December 1991. "Endangered, Threatened, and
Sensitive Vascular Plants of Nevada."
Nevada Natural Heritage Program. May 1992."Federal Threatened and Endangered Species
in Nevada."
New Mexico Department of Game and Fish State Game Commission. November 1990.
"Amended Listing of Endangered WBdJite of New Mexico.
Rutman, Sue/U.S. Fish and WMite Service. Summer 1992. "Handbook of Arizona's
Endangered, Threatened, and Candidate Plants."
Sivinski, Robert and Lightfoot, Karen. March 1992. "Inventory of Rare and Endangered
Plants of New Mexico."
-------
APPENDIX B
SPECIES LIST FOR ARIZONA'S EFFLUENT DOMINATED WATERS
-------
SPECIES LIST OF AQUATIC ORGANISMS
FOR ARIZONA'S EFFLUENT DOMINATED WATERS
Aquatic Plants
Aquatic Vascular Plant
Blue-green alga
Bulrush
Canary Reed Grass
Desaid
Diatom
Duckweek
Euglenoid
o
Filamentous Green Alga
Green Alga
Planktonic alga
Pondweed
Paspalus sp.
Polygonua sp.
Anacystis sp.
Chroococcus sp.
Microcystis sp.
Oscillatoria sp.
Schizothrix sp.
Spirulina sp.
Scirpus sp.
Phalaris sp.
Cosaarius sp.
Coloneis sp.
Fragellaria sp.
Leana minor
Euglena sp.
Eutreptie sp.
Phacus sp.
Cladophora sp.
Microspora sp.
Oedogonius sp.
Spirogyra sp.
Stigeoclonius sp.
Ulothriz sp.
Chlamydoponas sp.
Chlorella sp.
Chroococcus sp.
Tetracystis sp.
Ankistrodesaus sp.
Franceia sp.
Pediastrus sp.
Planktosphaeria sp.
Scenedespus sp.
Fotanogeton sp.
-------
Stonewort
Unicellular Green Alga
Water weed
Wild Rice
Yellow-green alga
Chara sp.
Nitella sp.
Oocystis sp.
Elodea sp.
Zizania sp.
Vaucheria sp.
Zooplankton
Copepoid
Copepod, Calanoid
Copepod, Cyclopoid
Ostraccxd (Seed Shriap)
Protozoa
Rotifer
Water Flea
Cyclops sp.
Eucyclops sp.
Unidentified sp.
Diaptoaus albuquerquensis
Unidentified sp.
Mesocyclops edaz
Unidentified sp.
Unidentified sp.
Didiniua sp.
Prorodon sp.
Brachionus bidentata (?)
Brachionus calycillirus (?)
Brachionus plicalilis (?)
Keratella sp.
Monommata sp.
Platyies polycanthus
Bosaina sp.
Ceriodaphnia sp.
Daphnia sp.
Monia aicrurus
Moina sp.
Unidentified
Macroinvertebrates
Bloodwora
Burrowing Water Beetle
Deaselfly
Chironoaus spp.
Pronoterus sp.
Enallagaa sp.
Ischnura sp.
-------
Divine Beetle
Dragonfly
Giant Water Bug
Horse fly
Hydra
Mayfly
Midge
Moth fly
Riffle Beetle
Snail
Springtail
Stonefly
Water Beetle
Water Boatzen
Water Scavenger Beetle
Water Strider
Wora
Deroectes roffi
Unidentified sp.
Progoaphus borealis
Unidentified sp.
Belostoaa sp.
Tabanus sp.
Hyda americana
Unidentified sp.
Rheotanytarsus sp.
Unidentified sp.
Psychoda sp.
Heterelais sp.
Physa sp.
Colembola sp.
Sweltsa sp.
Helichus imasi
Pseudocorize beameri
Enochrus pygmaeus pectoralis
Tropistemus ellipticus
Tropisternus lateralis
Tropistemus sp.
Gerris sp.
Unidentified sp.
Unidentified annelid
Fish
Bass, Largemouth
Bass, Yellow
Black crappie
Bluegill
Bullhead, Black
Bullhead, Yellow
Micropterus salmoides
Morone mississippiensis
Pomoxis nigromaculatus
Lepomis sacrochirus
Ictalurus melas
IctaJurus natalis
-------
Carp
Catfish, Channel
Catfish, Flathead
Fathead Minnow
Goldfish
Green sunfish
Guppy
Mosquitofish
Razorback sucker
Red shiner
Sailfm molly
Threadfm shed
Tilapia
Tilapia, Blue
Tilapie, Moseabique
Tilapie, Redabelly
Cyprinus carpio
Ictalurus punctatus
Pilodictis olivaris
Pimephales promelas
Carassius auratus
Chaenobryttus (Lepomis) Cyanellus
Lebistes sp.
Gaebusia affmis
Xyrauchen texanus
Notropis Lutrenis
Poecilia latapinna
Dorosoma pretenense
Tilapia sp.
Tilapia aurea
Oreochromis mossambicus
Tilapia zilla
Amphibian
Bullfrog
Rana catesbeiana
Rena sp.
Reptiles
Spiny softshell turtle
Sonoran aud turtle
Trionyz spiniferus
Kinosternon sonoriense
Source: Rationale for the Development of Toxic Pollutant Criteria
to Protect Aquatic and Wildlife Designated Uses. Airzona
Department of Environmental Quality.
-------
APPENDIX C
SPECIES INDIGENOUS TO EPHEMERAL WATERS
-------
POTENTIALLY INDIGENOUS ORGANISMS TO EPHEMERAL WATERS
Organism
Algae
Amphipod
Caddisfly
Damselfly
Duckweed
Freshwater Shrimp
Frogs/Toads
Mayfly
Midge
Mosquito
Protozoan
Worm
Comments
Endemic to all types of waters and moist habitats.
Found in lakes, ponds, streams, brooks, springs,
seeps, subterranean waters, and temporary ponds.
Inhabit cool and warm streams, seeps, rivers,
lakes, marshes, and temporary pools.
Most commonly found in permanent lakes, ponds,
and streams, but some may be adapted to
temporary ponds.
Common in slow moving streams and quiet waters.
Thirteen species known to exist in temporary and
astatic waters in Arizona.
Spadefoot toad and immature stages known to
inhabit ephemeral streams and temporary ponds
and pools. Frog data used as substitute for
spadefoot toad data.
Found in standing and running water. Many
Sonoran Desert species have life cycles of less than
two weeks and reproduce throughout the year.
Inhabit nearly all aquatic habitats.
Inhabit nearly all aquatic habitats.
Inhabit nearly all aquatic habitats.
In mud and debris of stagnant pools and ponds,
rivers, and lakes.
Notes: Data documenting the existence of organisms inhabiting
ephemeral waters in Arizona are rare. With two exceptions
(i.e., freshwater shrimp and mosquito), the above organisms
are assumed to be present in ephemeral "waters based on the
best professional judgement of academic researchers and
literature reviews. Department personnel continue to search
for evidence to substantiate the presence of these organisms
and make additions to the list when the data becomes available.
Source: Rationale for the Development of Toxic Pollutant Criteria
to Protect Aquatic and Wildlife Designated Uses. Arizona
Department of Environmental Quality.
------- |