Summary Report on
Cumulative Risk Assessment Practicum No. 2
(Phase I: Planning and Conceptual Model Development)
Prepared by:
Office of Science Policy
Office of Research and Development
U.S. Environmental Protection Agency
Washington, DC 20460
June 8, 1999
Draft
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Summary Report on
Cumulative Risk Assessment Practicum No. 2
(Phase I: Planning and Conceptual Model Development)
Prepared by:
Office of Science Policy
Office of Research and Development
U.S. Environmental Protection Agency
Washington, DC 20460
June 8, 1999
Draft
-------
Table of Contents
Preface 3
1. Introduction 5
2. Overview of the Planning and Scoping Process 5
3. Conceptual Model Development 6
3.1 Problem formulation 7
3.2 Societal goals and scientific endpoints 8
3.3 Conceptual Model Development 9
4. Hypothetical Case Study 10
5. Case Studies 14
5.1 The Chicago Cumulative Risk Initiative 14
5.2 Wood Preservative (PCP/HDWP) 15
5.3 Cumulative Risk Index Analysis for Concentrated Animal Feeding
Operations 18
6. Discussion and Next Steps 19
Appendix A. List of Participants A-l
Appendix B. Practicum Agenda B-l
Appendix C. Preliminary Case Study Materials C-l
Appendix D. Slides from Presentations D-l
Appendix E. Hypothetical Model Exercise E-l
Appendix F. Case Study Results from the Break Out Sessions F-l
Appendix G. Comments and Suggestions from Participants G-l
Appendix H. Draft Conceptual Model H-l
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Preface
EPA's practice of risk assessment is evolving from a focus on single pollutants within a
single medium towards integrated assessments involving suites of pollutants in several media that
may cause a variety of adverse effects on humans, plants, and animals, and also may have effects
on the processes and functions of ecological systems.
In July 1997, Administrator Carol Browner issued the Cumulative Risk Assessment
Guidance—Phase I Planning and Scoping, which set forth certain fundamental values to guide
the U.S. Environmental Protection Agency's (EPA's) risk assessment and communication efforts.
The Guidance directed all EPA offices to take into account the combined effects of multiple
environmental stressors in planning and scoping major risk assessments, and to integrate multiple
sources, effects, pathways, stressors, and populations where data are available. The Guidance
placed particular importance on the right-to-know opportunities for citizens and on enabling all
stakeholders to understand EPA's ongoing risk assessments and become involved in the decision-
making process.
The Guidance defines "cumulative risk" as the aggregate ecologic or human health risk
caused by the accumulation of risk from multiple stressors and pathways. The importance of
planning and scoping for cumulative risk assessments cannot be over-emphasized. As part of this
planning, risk assessors and risk managers are encouraged to define the dimensions of the
assessment, including the characterization of the populations (human and ecological) at risk.
These include individuals, sensitive subgroups (such as children, the elderly, or critical plant or
animal species). The Guidance also acknowledges that a broader set of important issues relating
to societal, economic, behavioral, and psychological stresses may contribute to adverse health
effects. The present state of data and science do not permit a quantitative assessment of risk that
encompasses these broader concerns, important though they are.
The Guidance identifies a set of eight key aspects of the risk assessment that risk
assessors, risk managers, technical experts, and stakeholders must determine during the planning
and scoping phase of risk assessment. They are:
1. Overall purpose and general scope of the risk assessment;
2. Products needed by management for risk decisions;
3. Approaches and consideration of the dimensions and technical elements that need to be
evaluated;
4. Relationships among potential assessment endpoints and risk management options;
5. Analysis plan and conceptual model;
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6. Resources (data, models, or other technical tools) required and available;
7. Identity of those involved and their roles; and
8. Schedule to be followed (including timely and adequate internal and external peer
reviews).
The "conceptual model" that emerges from the planning and scoping phase of the process
is a description or diagram of the relationships among predicted responses of a population of
concern and its stressors, including the environmental routes of exposure. The conceptual model
also contains an analytical plan that documents how data will be used, how endpoints will be
measured (directly or in surrogate), and what uncertainties exist.
The Science Policy Council's (SPC's) Cumulative Risk Working Group1, in order to
implement the Guidance, was directed to conduct a series of workshops intended to introduce the
concepts of cumulative risk planning and scoping throughout the Agency. The workshops, or
practica, are designed to offer guidance and training to EPA risk assessors on cumulative risk and
to bring EPA risk assessors and managers together to exchange information and experience in
implementing the Guidance. The first workshop was held in Washington, D.C. in July 1998.
The second practicum was held in Chicago, EL, on November 12-13, 1998, and attracted
more than 40 EPA, state, and Canadian scientists and risk managers. This practicum featured a
mix of presentations and facilitated discussions in both large and small group settings. Drs. Mark
Harwell and Jack Gentile, both of the University of Miami's Rosentiel School of Marine and
Atmospheric Science, lectured and facilitated the development of the cumulative risk conceptual
models through case studies of actual risk assessments going on in the Agency.
This report summarizes the highlights of this second practicum, including the information
that was presented and exchanged and key themes that emerged from the discussions, which are
highlighted throughout the report. The report is organized following the Practicum agenda.
Copies of the agenda, the case materials distributed to participants, a roster of attendees and
conceptual models drafted as a result of the second practicum are included in appendices.
'Donald Barnes (OA/SAB) Edward Ohanian (OW)
Ed Bender (ORD) Larry Reed (OERR)
Carole Braverman (Region 5) Joe Reinert (OPPT)
Pat Cirone (Region 10) James Rowe (ORD)
Penny Fenner-Crisp (ORD) Jeanette Wilste (ORD)
Michael Firestone (OPPTS) Bill Wood (ORD)
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1. Introduction
"Planning and Scoping for Cumulative Risk Assessments" occurs before the assessment begins. It
sets the stage for the questions that will be addressed through the analysis.
When asked about their thoughts upon hearing the term "Cumulative Risk Assessment,"
participants expressed the following ideas:
-resources
-integrated risk
-total environment
-relationship between risk assessors and risk
managers
-single vs multiple chemicals
-multiple compounds, multiple pathways
-difficulties in obtaining good data
-skepticism as to how to get good answers
-whole ecological system
-everything but incremental risk
-spectrum of kinds of assessments needed
-overall risk
-multiple risks
-potential exposure
-traditional and nontraditional, sources of
risk
-inclusive assessment
-complexity, challenges to decision making
-useful to public, how to integrate with site
specific risks
-complex interactions and relationships
-what people want
-uncertainty, unknowns-how to deal with
them
-total exposure-sources; similar
mechanism/mode of action of chemicals
-complex considerations, less than complete
data base but requiring decision; cradle to
grave; expanding scope to include
stakeholders—broad and complex in nature
-developing systemic approach
-need framework for scoping and strategies
to address
2. Overview of the Planning and Scoping Process
EPA's Guidance on Cumulative Risk Assessment: Phase I-Planning and Scoping draws
on the process and procedures described in the ecological risk assessment guidelines. Planning
and scoping begins with a dialogue between the risk manager and risk assessor to help define the
risk management needs for the assessment. For the long term, EPA's Risk Assessment Forum
(RAF) is developing a framework for cumulative risk assessment guidelines which will discuss
traditional approaches for performing risk assessments.
This workshop addresses the preparations for the risk assessment, which involves
discussing what to include or exclude from the risk assessment through brainstorming, identifying
participants and contributors, and formulating stressor-response hypotheses. These principles are
applied to both hypothetical and real case studies. Definitions of cumulative risk are developed in
context on a case by case basis.
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The planning and scoping guidance includes these basic steps: 1) problem formulation
dialogue (risk assessors, risk managers, stakeholders, economists, etc); 2) defining the purpose of
the risk assessment; and 3) developing a conceptual model. The conceptual model is a hypothesis
about the relationship between stressors (biological, chemical or physical promoters of some
effect) and endpoints (receptors). Human health assessors are still trying to determine if this is a
useful process.
Definition of Cumulative Risk
1. Who is affected or stressed?
2. What are the stressors?
3. What are the sources?
4. What is the time frame for the
risk(s)?
5. What are the assessment
endpoints?
Questions and Discussion:
Integrated vs Cumulative Risk? In this case,
these terms are almost equivalent. The use of
the term "dimension" in the Guidance may be
confusing. (Some think it refers to spatial
aspect like landscapes).
Should stakeholders be in dialogue with risk
assessors and risk managers? In the model
derived from ecological guidelines, problem
formulation occurs within EPA as a scientific
task. There are internal discussions within
EPA on this point. Some interpret the
ecological guidelines to say this is a scientific
endeavor. We are trying to find that boundary
between the risk assessment and this broader discussion.
Cumulative risk assessment is neither generic nor consistent across the Agency. On the
one hand^are site-specific Superfund and RCRA assessments, while, on the other hand, there are
air and water rules which set national standards. We cannot resolve differences across programs
here. Those issues will be addressed in cumulative risk guidelines and other projects.
In the SPC guidance, we are trying to capture needs across the Agency while deferring to
offices for specifics. The guidance encourages using other sources of help and input. At this time,
cumulative risk planning and scoping is a qualitative process, but it could become quantitative if
we choose to bring data to the discussion. Planning and scoping provides a broad foundation for
cumulative risk assessment and allows users to develop a reasonable subset of decisions upon
which to move forward. This process provides benefits in many situations. The RAF will address
this issue in the future. It is necessary to break down the problem of cumulative risk into bite-
sized pieces. This process can be exceedingly difficult, but we need to listen to the questions
asked by risk managers and stakeholders and to frame our approach to address those questions.
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3. Conceptual Model Development
Dr. Mark Harwell explained that the risk assessment process has evolved over the past
twenty years. The basic structure of a risk assessment includes: hazard assessment, exposure
assessment, and risk characterization as described by the National Research Council (NRC) in
1983. Ruckelshaus incorporated this paradigm into Agency policy. The Agency also
distinguished between risk assessment and risk management. Due to concern about risk managers
"having a on thumb on scale" (Gorsuch era); the Agency kept a "bright line" that separated risk
assessment from risk management so that risk assessments would not be biased by non-scientific
factors. This separation between risk assessment and risk management still is maintained in parts
of the Agency.
Since the 1980's, there has been more consideration to entwining risk assessment and risk
management in documents, including the ecological risk guidelines, cumulative risk guidance, and
recent National Academy of Science (NAS) recommendations on "Understanding Risk". The
Agency also has attempted to rank risks in its 1985 "unfinished business" project, and in the
Science Advisory Board's (SAB) 1988 "reducing risk" project. This project recommended that
EPA elevate ecological risk in addition to human health. The process used by the Risk
Assessment Forum to develop an ecological risk framework (1992, 1997) put together a structure
to tackle more difficult problems while understanding many uncertainties still exist.
The "Framework for Eco Risk Assessment" found that the Agency had concerns about
multiple chemicals. They said that the "Red Book" paradigm was insufficient to deal with
ecosystems and the multiplicity of risks, and that EPA needed a more broadly defined paradigm.
The framework also expanded from a focus on chemicals to stressors (agents of change).
Stressors are any change leading to ecological effect (physical, chemical, biological stresses).
Stressors also may include psychological and economic factors.
3.1 Problem formulation
The first stage in the process is problem formulation, in which the scope, spatial extent,
goals, initial ideas on stressors, human activity, and other issues are discussed. At present, the
problem formulation phase is more developed for ecological risk assessment, but it has parallels in
human health risk assessment. In fact, the terms "planning and scoping" and "problem
formulation" mean much the same thing. A major output of the planning and scoping phase is a
conceptual model leading to the analysis phase (qualitative or quantitative in nature), which leads
to development of an analysis plan. The analysis plan is a scientific planning activity which
includes sensitivity and uncertainty analyses and conclusions about endpoints for the assessment.
This type of preliminary thinking and dialogue is essential to promote adaptive management-a
flexible way of making decisions that also deals with uncertainties, which we have found valuable
in dealing with stakeholders.
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Human Health Risk Assessment
Hazard Identification
Exposure Assessment
Ecological Risk Assessment
Selection of end points
Characterization of ecosystems, communities,
and populations potentially at risk
In ecological risk, any human action can affect an ecosystem. In problem formulation
(planning and scoping) for ecological risk assessment, we distinguish significant from trivial
actions (based both on societal concerns and ecological impacts). We define a parsimonious set
or suite of health changes and identify those that really matter (in terms of Economic or societal
consequences). For the risk assessment, we measure endpoints and surrogate measures. The
conceptual model is a graphical representation of these societal drivers, environmental stressors,
and ecological effects. In planning and scoping for cumulative risks in the human health context,
we follow the same problem formulation approach for systems at risk from similar stressors.
3.2 Societal goals and scientific endpoints
Goals for society are set by society and constrained by science. The goal must be
established first (e.g., restore everglades). Science translates what that means (i.e, ecosystem
attributes of importance). Endpoints are the bridge between society and science. Measures are
chosen as a scientific function to address a technical question. There needs to be a feedback loop
to ensure that the technical question supports measuring attainment of the goal. The NRC (1996)
discussed the feedback loop as an analytic deliberation that is an iterative process. The basic
concept of this iterative process is what the Agency is struggling to adopt through the cumulative
risk guidance. The current EPA Science Advisory Board (SAB) project on integrated risk also is
working on this problem.
Dr. Harwell described categories of ecological endpoints, noting that they were different
for different ecosystems. These ecological endpoints increase in complexity from endangered
species and population survival to landscape-level endpoints. A comparable set of endpoints for
human health should be developed. There also is an interesting set of interactions between
ecological and human health concerns (e.g., vectors may have direct relevance to human disease;
plants producing cancer drugs). Some of these could be added to the cumulative risk guidance.
Dr. Harwell presented a comparative ecological risk assessment from Tampa Bay, where
the Port Authority compared the potential impacts of a spill of two chemical mixtures (oils). He
explained the endpoints of concern, critical habitats (including sea grass beds, mud flats, and
marshes), and systems at risk, to be assessed. The physical processes in fate and transport models
for fuel oils were key elements in the study. Toxicity tests were conducted on principal biota.
Risks were evaluated under scenarios for shipping the oil with selected sets of conditions for
comparing stressors. The audience found that the conceptual model was very helpful for defining
the scenarios and interpreting the data.
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3.3 Conceptual Model Development
Dr. Jack Gentile discussed principles and examples for developing conceptual models. A
conceptual model is a spatially explicit graphical or text description of the candidate causal
linkages among sources, stressors, receptors and endpoints describing the spectrum of potential
risks. He recommended the following steps for developing conceptual models:
1. Define the goals and assessment context.
2. Delineate scales and boundaries.
3. Inventory land uses/activities.
4. Describe potential stresses and sources.
5. Identify contaminant release mechanisms.
6. Describe exposure pathways.
7. Identify health/ecological endpoints.
8. Determine specific health/ecological endpoints..
9. Determine specific health/ecological measures.
10. Develop a suite of risk hypotheses.
11. Rank relative importance of potential risks.
Dr. Gentile also presented a General Conceptual Model Sequence, as follows:
Societal Drivers=»System stress=>Stress regime/Exposure Pathways=>Disturbance/Stressor Co-
occurrences with Receptors=»Primary/Secondary Effects=»Health/Ecological
EndpointsHvIeasurements
He described several examples to demonstrate some of the principles and methods listed
above. Highlights are summarized here. (See the appendix for additional information). The first
example is the Waquoit Bay Conceptual model. Dr. Gentile showed how the sources (drawn
from human activities) might contribute to exposure. He also discussed how to aggregate kinds
of stressors (toxics, nutrients, etc.), system stressors toward ecologic effects, and measurement
assessment endpoints. He noted that it helps to identify how various stressors affect the
ecosystem and to prioritize stressors. One must choose how to partition out major stressors and
determine whether and how are they acting independently or synergistically. For example, are
major stressors acting cumulatively on an endpoint or across endpoints in interrelationships? He
also recommended that each pathway be developed independently and then put back together in
the context of the complete model. Dr. Gentile showed another example that used an Impact
Matrix for Green Bay, which involves looking at nutrient loading (stressors) vs impact criteria
(human health, aesthetics). In this example, major gaps were determined with BPJ.
Drs. Gentile and Harwell applied these processes to a set of water resource management
problems for South Florida which involved extensive interaction among governments and other
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stakeholders. Initially, societal goals were developed in order to get stakeholders and scientists to
discuss both the science of the problem and restoration options. Here, societal goals guided
science efforts. A Governor's Commission was created, and the commission was effective in
promoting cooperation between the groups. He described spatial boundaries of the risk
assessment using ecological criteria, hydrological criteria, and physiological
transcripts/designations (sawgrass, mangrove estuary, etc). (The conceptual model Dr. Gentile
described is included in Appendix D).
For the analysis phase for the Biscayne Bay model, hydrology was the major factor. In
fact, hydrology was found to have impacted all 13 different models used in the study. To confirm
this, the best relationship was selected, and a holistic model incorporating the concerns for each
endpoint was used.
A member of the audience asked how to establish performance criteria for each stressor.
Criteria for impact will be different across stressors. He was told that you can rank major
stressors and dominant effects to be sure they are represented in the conceptual model.
The discussion also highlighted an example of the development of RI/FS conceptual site
models being developed for a Superfund site in a western state. The problem in the example was
mining waste that was distributed over many miles of a watershed and reservoir system. Mining
waste was represented by a chemical-physical stressor model. Effects were both ecological and
human health. The basin was subdivided using geology, hydrology, and ecology into five sub-
basins, a series of potential watershed segments. For each sub-basin the habitat and contaminant
levels were graded. Inputs, release mechanisms, affected media, exposure routes, receptors and
systems, effects, endpoints, and measures were estimated for each sub-basin. Geography,
topography and sediment movement were also evaluated for remediation options. Based on
contaminant levels, two segments were termed heavily polluted. Biota were characterized
according to class 1 streams through generalized models.
The conceptual model was constructed from the preliminary process models and the
biological models. Most important pathways were determined from the most likely exposures and
endpoints of greatest concern. For humans, ingestion offish and inhalation of contaminants in
domestic water supplies are being scrutinized as major routes. The chemical-physical process
model links the stressors to both ecological concerns and human health concerns. The conceptual
model also has helped identify key characteristics of remediation approaches.
4. Hypothetical Case Study
Dr. Harwell described a hypothetical case involving an industrialized and agricultural
watershed. The scenario (See Appendix E) involves a new hazardous waste incinerator which has
been proposed for this area. The community was concerned about the cumulative risk associated
with this additional source of air emissions and solid waste. Dr. Harwell led the group through an
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exercise using the planning and scoping guidance to define cumulative risk for each of the possible
dimensions, narrow the possibilities to a parsimonious set, and develop a conceptual model.
The group brainstormed ideas on risk dimensions. These are summarized below:
o Sources: Single sources, point sources, non-point sources; multi-sources: combination of those
above
o Stressors (by source category):
- Agriculture—stressors-nutrients, pesticides, sedimentation, particulates
- Petrochemicals-stressors—toxic organics, criteria air pollutants, toxic inorganics, hydrocarbons
- Industrial— stressors— ammonia, S02, particulates, metals, temperature, economic =noise,
odors, cultural, aesthetics, property values
- Aquaculture stressors—nutrients, pesticides and drugs, disease/pathogens, exotic species,
odors, habitat alteration-wetland conversion, levee, hydrologic effects
Urban Stressors— pesticides, nutrients, toxic organics, toxic inorganics, flooding (physical),
mobile air emissions, habitat alteration, turbidity, PAHs, pathogens, exotic species,
Societal: thermal increases, odor, noise, air pollutants, crowding
Receptors: (what's at risk?)
(eco receptors usually talking about populations or higher not single species)
Aquatic Habitat Human
-fish -women of child-bearing age
-amphibians -worker populations
-macrophytes -respiratorily sensitive
-water fowl -subsistence fishers
-macro invertebrates -swimmers
-trophic structure (?)
Endpoints (what should you worry about/minimal set)
Ecological (aquatic) Human Health (go to specific Dose Response level)
-biodiversity-community -cancer (bladder)
richness, evenness -the array in the guidance
-habitat quality-eco - respiratory
-water quality-eco - (may want to go back and do attributable
risk exercise; 4x increase in bladder cancer)
-economic fish health-pop - capture endpoints people care about!!!!
-critical species loss-pop
-habitat species/seagrass-pop
-ephemeral wetland loss-landscape
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It was noted that it is important to look at similarities and dissimilarities of eco and human
risk assessment. For example, .causation is always a problem in human health risk assessment and
this is a factor that differentiates human health from eco risk assessment.
Dr. Gentile presented a hypothetical case example for cumulative risk which incorporated
both ecological and human risk concerns. (See Appendix E). After discussing the case example,
Dr. Gentile reviewed the six basic cumulative risk questions used to flesh out details on sources,
stressors, exposure pathways, single species routes, community/ecosystem routes, receptor
categories at risk, and human health and ecological endpoints that are incorporated into the
conceptual model. Based on the hypothetical case example, a preliminary conceptual model was
sketched out to illustrate the approach that could be taken.
Observations of the group
1. Include quality of life as an endpoint.
2. It is not a good idea to present complex models to uneducated stakeholders, but if you get
them to help you build the model, you can get buy-in. You must get stakeholders
involved.
3. Important to work with stakeholders on endpoints of significance.
4. Different parts of country will accept different levels of risk.
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SOURCES
AGRICULTURE
URBAN
STRESSORS*
ENDPOINTS*
FISH POP.
(SUSTAINABLE
AQUACULTURE
PETRO-1NDUSTRIAL
AIR POLLUTANTS HABITAT TURBIDITY
(S02/N02, PARTI- I ALTERATION
CULATES
RESPIRATORY
CANCER
NEUROTOX.
QUALITY OF
LIFE
* It is critical to identify what are the mechanisms/causal relationships between stressors and endpoints.
Conceptual Model developed at the Practicum for the Hypothetical case.
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5. Case Studies
On the second day of the workshop, Mark Harwell introduced the EPA case studies.
They are: 1) the Chicago Cumulative Risk Initiative(CCRI), presented by Carole Braverman
(Region V); 2) Wood Preservative (PCP/HDWP) , presented by Nader Elkassabany and Wanda
Jakob (Office of Pesticide Programs): and 3) the Cumulative Risk Index Analysis for
Concentrated Animal Feeding Operations (CAFO), presented by Gerald Carney (Region VI). The
three cases represent a spectrum of cumulative risk problems in the broadest sense. They concern
human health and ecological impacts, and involve place-based and national assessments. All are
multimedia and all are presently underway. Also, each has significant stakeholder involvement
outside the Agency. The case materials for each study are provided in the Appendix.
Practicum participants were divided into three break out groups to focus on the
application of planning and scoping guidance for each of these cases. Each group worked
separately. Case presenters provided an introduction to the problem and facilitators led each
group through the guidance.
Each case study summary below is followed by the break out group's report. Comments
and suggestions pertaining to each case study are shown in boxes.
5.1 The Chicago Cumulative Risk Initiative
The Scenario
The Chicago Cumulative Risk Initiative (CCRI) is a multi-Office effort to measure and
reduce the risks posed to residents of the Chicago metropolitan/Northwest Indiana areas by
cumulative exposure and hazard. CCRI was initiated in response to a Toxic Substances Control
Act §21 Citizen's Petition from eleven Chicago-area community advocacy groups. The Petition
focused upon the regulatory gap in the Clean Air Act that allowed industrial air permits to be
approved on a site by site (rather than cumulative) basis. The advocacy groups' purpose in
submitting the Petition was to convince the Agency to implement activities that would measure
and mitigate the cumulative risks faced by area residents. CCRI's focus has expanded beyond the
limited, sector- and media-specific concerns (e.g., incinerator siting) originally expressed in the
§21 Petition to include information and planned action on multi-media sources of pollution. CCRI
consists of four phases:
Phase I: Generating the environmental loading profile.
The Agency will establish quantities and destination of toxics
released into the Chicago-area environment.
The Agency will analyze this data to approximate cumulative
environmental and human exposure.
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Phase II:
Phase'
Phase IV:
The Results
Convening a facilitated workshop to discuss loading profile data, risk assessment,
and pollution prevention/remediation options.
The Agency will work with State/local regulators and community
groups (Stakeholders) to create a consensus on data interpretation,
calculation of the toxics hazard, and the general approach for
"cumulative"risk analysis.
Performing "cumulative" risk assessment.
The Agency will act to develop the consensus procedure (from
Phase II) into a scientifically valid methodology for approximating
cumulative risk for residents of the Chicago metro area.
Implementing Pollution Prevention/Remediation activities (e.g., initiating industry
negotiations, public education campaigns).
CCRI Evaluation Comments
• Covered basic elements and the conceptual
model very effectively.
• Take environmental justice into account.
• Stakeholder involvement discussion was
limited.
This break out group defined the
problem, goals, stakeholders, stressors, sources,
and endpoints, and presented a simplified flow
diagram/conceptual model for the risk assess-
ment. Ecological risk was separated from human
health risk for later discussion. They concluded
that the cumulative risk conceptual model is
really a "living document" and should be subject
to iterative changes and refinement by the stakeholders as the study progresses. The group started
with sources and identified stressors (ozone, particulates, lead), defined the media (air, soil,
water) and pathways (inhalation, contact, ingestion), and identified potential diseases and health
impacts (such as eye irritation, asthma, neurological effects). They developed similar but separate
approaches for ecological risks. They developed measurement tools to recognize effect levels and
monitor trends over time.
The group reported that they benefitted from having participants who were very familiar
with the case, the available data, and the risk assessment. Many of the group members felt that
having a better understanding of environmental conditions in Cook and Lake Counties would help
future permit decisions and communication with stakeholders. It also would help in framing
societal goals within the region.
5.2 Wood Preservative (PCP/HDWP)
The Scenario
Pentachlorophenol (PCP) is used throughout North America as a wood preservative. PCP
is used primarily in the treatment of utility poles, and also is used to treat railroad crossties, wood
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pilings, fenceposts, and commercial/residential decks. PCP is teratogenic, fetotoxic, and
oncogenic, and has been banned from use on all non-wood applications since 1987. It is classified
as a "probable human carcinogen." The risk assessment is driven by PCP's Reregistration
Eligibility Decision Document, which is due in 1999, and will consider FIFRA, FQPA, Clean
Water Act, Clean Air Act, RCRA, and input from the North American Free Trade Agreement
(NAFTA). Stakeholders include industry and trade associations, environmental groups, and the
public. Unlike the other cases discussed in the workshop, the PCP risk assessment does not
address a particular site-it is nationwide in scope.
The hazard identification will examine all available data for acute toxicity, developmental
effects, chronic effects, carcinogenicity, and endocrine effects. Epidemiological studies and
pesticide incident data will be used as available. PCP is highly toxic to fish (acute and chronic),
moderately toxic to birds in acute oral doses, but is virtually nontoxic to birds in dietary doses.
Human exposure scenarios include occupational exposure (wood treatment workers; construction
workers). Primary pathways are dermal absorption, inhalation of treated dust and aerosol, and
ingestion (indirectly, from contaminated hands). Environmental exposure pathways under
consideration include emissions from utility poles and other treated lumber via air, soil, and water
routes. Uncertainties and remaining issues include the statutory overlaps, disposal of treated/
contaminated wood after service, limited emissions data, and a focus on individual risk.
The Results
The group began with a presentation on highlights of the regulatory history, chemistry,
usage, hazard identification and human and environmental exposure concerns, including the issue
of microcontaminants.. The group agreed to a process that involved identification of sources,
stressors, pathways and endpoints for a conceptual model, primarily focused on PCP and
microcontaminants. A previous ranking exercise on human and environmental sources and
pathways, which was completed at the last practicum, was the basis for ranking the degree of
exposure (low, medium or high). The ranking relied on professional judgement.
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HUMAN
Occupational
Accidental (L)*
Occupational (H)*
Occupational (L)
Occupational (RCRA)
Children (L) (?)
(L)
(L)
Residential Occupational
(L)
ECOLOGICAL
Aquatic
Spill
Aquatic (L)
Soil (L)
Aquatic (H)
SOURCES
Manufacturing
Transport [of chemicals and logs]
Wood Preservative Facility
Utility Poles [localized]
Disposal of Treated Poles [consumer misuse]
i
1 Residential Uses (e.g., decks)
Soil (L) ! Fences
Aquatic
Soil/Water (H)
(L)
Pilings, Piers, Docks
Remedial Ground line Treatment
Farm buildings/Industrial buildings
*L=Low, H=High
Human Pathways/Routes of Exposure
SOURCE
Manufacturing
Transportation
Wood Preservative Facility
Utility Poles
Disposal of Treated Poles
Residential Uses/ subpopulation-children
Fences
Pilings, Piers, Docks
Remedial Ground line treatment
a. Occupational
b. Residential
Farm Buildings/Industrial Buildings
DERMAL
High
High
Low
Low (RCRA Issue)
Medium - children
Low
Low (N/A)
Low
High
Low
INHALATION
Low
Medium
Low
Low
Low
Low
Low
Low
Low
Low
INGESTION
Low
Low
Low
Low
Medium
Low
Low
Low
High
Low
17
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The group used a broad pathway design with major sources at top, followed by stressor
sources, pathways and major habitats impacted (a Biscayne Bay model). Major habitats of
concern were evaluated and a table of receptor habitats and endpoints affected by PCP and
dioxins/furans was developed. For example, for soils: earthworms, microbes and invertebrates
were highlighted as potentially affected endpoints. The group also attempted to construct a
rough conceptual model. (Detailed notes from the breakout group are included in Appendix F).
As follow-up to its discussion, the group developed an example of a draft human health
PCP conceptual model. (See Appendix H). Participants emphasized that the final conceptual
model should be accompanied by a detailed narrative that describes the thought process and basis
for the conceptual model design.
5.3 Cumulative Risk Index Analysis for Concentrated Animal Feeding Operations
The Scenario
Concentrated Animal Feed Operations (CAFOs) are a common and significant concern
throughout Region 6. CAFOs are large (significantly so in terms of watershed areas) and produce
enormous quantities of waste discharge into on-site lagoons. These lagoons and associated
operations are permitted under the Clean Water Act's National Pollutant Discharge Elimination
System (NPDES) and require environmental impact reviews under the National Environmental
Policy Act (NEPA). NEPA requires "cumulative" evaluations of the proposed threat. For some
watersheds which are not meeting state-prescribed standards, there may be Total Maximum Daily
Load analyses and additional restrictions or penalties imposed. There is also public concern over
the rapid expansion of CAFOs. EPA needs to determine when a watershed reaches a significantly
polluted or impacted state, but there currently is no method or approach for doing so. The risk
evaluation was requested by Region 6's Enforcement Office due to the NEPA requirement
inherent in the NPDES review for waste lagoons.
Stakeholders include Region 6 program managers and staff (involved with NEPA
enforcement, NPDES permits, watershed quality, groundwater, surface water, risk assessors,
RCRA, Superfund, and GIS experts), academics, industry (primarily swine production), state
regulators, EPA headquarters (NEPA, agriculture center), Department of Agriculture's Natural
Resource Conservation Service, environmental groups, and residents.
The cumulative/multimedia aspect to CAFOs include surface water contamination
(ecological and human health), drinking water contamination from surface water and
groundwater, microbiological/pathogen hazards from wastes, statutory overlap (CWA, CAA,
NEPA, FQPA, RCRA), and multiple pathways and routes of exposure. In addition to the concern
from waste lagoons, there is a significant public concern with odors.
Region 6 developed a new approach based upon a mathematical algorithm that established
the potential for significant environmental risk (CRIA) for each CAFO.
18
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Watershed Unit Subarea
CRIA = (Total Affected Area + Watershed area)
(scale of 1-4)
Degree of Vulnerability
(scale of 1-5)
Degree of Impact
(scale of 1-5)
The Results
The case-study break out group developed lists for each dimension in the Cumulative Risk
Guidance. They also developed separate lists for assessment and measurement endpoints. The
initial discussions clarified the terms "stressor" and the "sources of stress" from a concentrated
animal feeding operation. Several members of the group indicated that, in the states in which they
worked, feedlots and suburban development were in direct conflict. One participant noted that
feedlots were on the ballot of twenty states in recent elections.
CRI Evaluation Comments
CRIA approach to screening was very useful.
Helpful ideas for risk managers. Needed
more time to explore the model and linkages.
Slow starting, but valuable. Need to clarify
dimensions and process for building the
models.
Although skeptical at first about the topic of
animal feedlots, it was an interesting and
important issue.
The group identified several issues that
were unusual to this case study. For example,
the primary human concerns concerned quality
of life impacts (in terms of odor and nuisance)
from the facilities rather than health effects.
They also noted that cumulative effects from
multiple facilities within the same watershed also j
could be examined. The group did not reach
agreement on how to develop a preliminary
conceptual model. They concluded, however,
that Region 6's CCRI tool appeared to be
valuable for screening site-specific decisions,
such as facility siting.
6. Discussion and Next Steps
Meeting in plenary session, Practicum participants raised several issues and made several
suggestions about how to improve Agency efforts for planning and scoping for cumulative risk
assessment, and about future workshops on the subject, including the following:
1. Take things a step further in next practicum; Develop a framework for Cumulative Risk
Assessment.
2. Value in taking conceptual model further in development (more detail, reality check in
process).
3. Clarify the scope in terms of spatial extent of the problem to be addressed.
4. I am optimistic after working through diagrams, at least possibility for future; need to
identify important threats and problems with a transition away from programmatic to
multi-media risk assessments.
5. It is normal that we do not have a complete database. We need a method to zero in the
most important decisions/risk.
19
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Participants made several comments and raised a series of closing questions, including the
following:
- When and how should we engage stakeholders?
- Cumulative risk assessment should be used beforehand to organize thoughts and present to
public, get feedback from public and then revising conceptual model
- Endpoints will be highlighted by stakeholders
- Includes exposure, habits, activity patterns
- Stakeholder meetings should be held to introduce them to conceptual model approach; trade-
offs will be forced by such meetings; need to involve at some point; prioritize issues.
20
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Appendix A. List of Participants
Cumulative Risk Practicum Participants
Chicago - November 12-13,1998
Elmer W. Akin
EPA/Region 4 (AFC-EPA/WD)
61 Forsyth Street, SW
Atlanta, GA 30303
(404) 562-8634
Edward Bender
EPA/ORD (8103R)
401 M Street, SW
Washington, DC 20460
(202) 564-6483
Carol Braverman
EPA/Region 5
77 West Jackson Blvd.
Chicago, IL 60604
(312)886-2910
John Connell
EPA/Region 5 (DT-J)
77 West Jackson Blvd.
Chicago, IL 60604
(312)886-6832
Arunas K. Draugelis
EPA/Region 5 (SR-6J)
77 West Jackson Blvd.
Chicago, IL 60604
(312) 353-1420
Priscilla Fonseca
EPA/Region 5 (OT-8J)
77 West Jackson Blvd.
Chicago, IL 60604
(312) 886-1334
Mike Beedle
EPA/Region 5 (DE-9J)
77 West Jackson Blvd.
Chicago, IL 60604
(312)353-7922
David Belluck
MPCA
520 Lafayette Road
Saint Paul, MN 55906
(612) 296-7874
Lisa Capron
EPA/Region 5 (DE-9J)
77 West Jackson Blvd.
Chicago, IL 60604
(312)886-0878
Harriet Croke
EPA/Region 5 (DRP-8J)
77 West Jackson Blvd.
Chicago, IL 60604
(312)353-4789
William Enriquez
EPA/Region 5 (DW-8J)
77 West Jackson Blvd.
Chicago, IL 60604
(312)886-1484
Jack Gentile
Center for Marine & Environmental
Analyses Rosenstiel School of Marine
and Atmospheric Science
University of Miami
4600 Rickenbacker Causeway
Miami, FL 33149-1098 USA
A-l
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Mark Harwell
Center for Marine & Environmental
Analyses Rosenstiel School of Marine
and Atmospheric Science
University of Miami
4600 Rickenbacker Causeway
Miami, FL 33149-1098 USA
Margaret L. Jones
EPA/Region 5 (DT-8J)
77 West Jackson Blvd.
Chicago, IL 60604
(312)353-5790
Brenda Jones
EPA/Region 5 (SR-6J)
77 West Jackson Blvd.
Chicago, IL 60604
(312)886-7188
Lawrence Lehrman
EP A/Regie® 5 (MG-9 J)
77 West Jackson Blvd.
Chicago, IL 60604
(312)886-0836
Karen McCullagh
(PMRA)
Room E-735
Sir Charles Tupper Blvd.
2250 Riverside Drive, A.L. 6607E
Ottawa, Ontario, Canada Kl AOK9
William L. MacDowell
EPA/Region 5 (AE-17J)
77 West Jackson Blvd.
Chicago, IL 60604
(312)886-6798
Mario Mangino
EPA/Region 5 (DRP-8J)
77 West Jackson Blvd.
Chicago, IL 60604
(312)886-2589
Caje Rodrigues
(PMRA)
Room E-735
Sir Charles Tupper Blvd.
2250 Riverside Drive, A.L. 6607E
Ottawa, Ontario, Canada Kl AOK9
Marvin Hora
MPCA
520 Lafayette Road
Saint Paul, MN 55155
(931)296-7201
Chuck Maurice
EPA/Region 5 (DW-8J)
77 West Jackson Blvd.
Chicago, IL 60604
(312)886-6635
A-2
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Daniel Mazur
EPA/Region 5 (DW-8J)
77 West Jackson Blvd.
Chicago, IL 60604
(312)353-7997
Patricia Morris
EPA/Region 5 (AR-18J)
77 West Jackson Blvd.
Chicago, IL 60604
(312)353-8656
Colleen Olsberg
EPA/Region 5 (DRP-8J)
77 West Jackson Blvd.
Chicago, IL 60604
(312)353-46-86
Amy Pelka
EPA/Region 5 (B-19J)
77 West Jackson Blvd.
Chicago, IL 60604
(312) 886-9858
Joseph C. Reinert
EPA/OPP (2129)
401 M Street, SW
Washington, DC 20460
(202)260-0512
James Rowe
EPA/ORD (8103R)
401 M Street, SW
Washington, DC 20460
(202) 564-6488
Meagan Smith
EPA/Region 5 (DW-8J)
77 West Jackson Blvd.
Chicago, IL 60604
(312)886-4446
Rosita Clarke-Moreno
EPA/Region 5 (SR-6J)
77 West Jackson Blvd.
Chicago, IL 60604
(312)886-7251
Amy Mysz
EPA/Region 5 (DRP-8J)
77 West Jackson Blvd.
Chicago, IL 60604- •'
(312)886-0224
Michele Palmer
Department HHHS (ORHA)
105 W.Adams, 17th Floor
Chicago, IL 60604
(312)353-7800
Larry Reed
EPA/OERR(5201G)
401 M Street, SW
Washington, DC 20460
(703) 603-8960
George Bollweg
EPA/Region 5 (DW-8J)
77 West Jackson, Blvd.
Chicago, IL 60604
(312)353-5598
Margaret Sieffert
EPA/Region 5 (AE-17J)
77 West Jackson Blvd.
Chicago, IL 60604
(312)353-1151
Mary Beth Smuts
EPA/Region 1 (CPT)
JFK Federal Building
Boston, MA 02203
(617)565-3232
A-3
-------
Maryann Suero
EPA/Region 5 (AR-18J)
77 West Jackson Blvd.
Chicago, IL 60604
(312)886-9077
Bilue Thomas
EPA/Region 2 (DEPP/MPB)
290 Broadway
New York, NY 10007
(212) 637-3768
Winona Victery
EPA/Region 9 (PMD-1)
75 Hawthorne Street
San Francisco, CA 94105
(415)744-0121
Amary White
EPA/Region 5 (T-13J)
77 West Jackson Blvd.
Chicago, IL 60604
(312)353-5878
Lucy Stanfield
EPA/Region V(B-19J)
77 West Jackson Blvd.
Chicago, IL 60604
(312)353-3440
Alan Walts
EPA/Region 5 (C-14J)
77 West Jackson Blvd.
Chicago, IL 60604
(312)353-8894
Howard Zar
EPA/Region 5 (B-19)
77 West Jackson Blvd.
Chicago, IL 60604
(312)886-1491
A-4
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Appendix B. Practicum Agenda
Cumulative Risk Assessment Workshop
(Phase I: Planning and Conceptual Model Development)
November 12-13, 1998
Chicago, 111.
Room 328
77 West Jackson Boulevard
Agenda
Purpose: Demonstrate the use of the Cumulative Risk Assessment Guidance (Planning and
Scoping) process and the Ecological Risk Assessment Guidelines principles for developing
cumulative risks from multiple sources over a range of spatial scales. Illustrate the feasibility of
the planning and problem formulation phases for identifying critical issues such as public values
and perceptions, defining sources of stress and potential assessment endpoints and indicators and
finally demonstrating the utility and value of conceptual models in the assessment and decision
making process.
November 12.1998
8:00 Registration
8:30 Welcome - David Ullrich, Regional Administrator (Acting)
Introduction of the Cumulative Risk Assessment
Theme - Ed Bender
- Participant introductions and expectations
- Highlights of the Cumulative Risk Assessment Guidance
9:30 Overview of Scoping/Planning Process - Mark Harwell
Conceptual Model Development - Jack Gentile
Broad overview of the risk planning process and experience of the outside
experts. Include each step through the conceptual model. The model presentation
will highlight the principles and process for developing conceptual models,
employ examples to illustrate the diversity of models, and discuss how conceptual
models could be used to engage decision makers and stakeholders. Cumulative
Risk Guidance and Ecological Risk Guidelines will also be compared.
B-l
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12:00-1:15 Lunch
1:15 Introduction of Hypothetical Case Study and Practicum - Mark Harwell
A single case study will be used to give participants an opportunity to apply the
planning and scoping guidance and actually develop a conceptual model. The
hypothetical case study reflects both non-chemical and chemical categories of
stressors as well as both ecological and health concerns. Step through each part of
the planning and scoping and problem formulation process."
4:15 Recap
4:30 Adjourn
November 13.1998
8:00-8:30 Introduction to EPA Case Studies and Instructions to Work
Groups - Mark Harwell
8:30 Adjourn to work groups
Case Study Presentation (Leaders)
Work groups will develop planning and scoping and develop
conceptual models
Case Study 1
Chicago Cumulative Risk Initiative - Carole Braverman
Case Study 2
Wood Preservative (Pentachlorophenol) - Nader Elkassabany, Wanda Jakob
Case Study 3
Cumulative Risk Index Analysis (CAFOs) - Gerald Carney
12:00-1:15 Lunch
1:15 Continue work in break outs
3:00 Report Out, Discussion and Next Steps - Ed Bender
4:00 Adjourn (Debrief with Case Presenters)
B-2
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Appendix C. Preliminary Case Study Materials
C-l
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Cumulative Risk Assessment Practicum
Case Study Draft
Cumulative Risk Index Analysis
(Swine Concentrated Animal Feeding Operations)
Region VI
Prepared for Practicum
November 12-13, 1998
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CUMULATIVE RISK INDEX ANALYSIS (CRIA)
(Swine Concentrated Animal Feeding Operations)
Introduction
Regulated, concentrated Animal Feeding Operations (CAFOs) are open
lots or facilities where animals have, been, are, or will be
stabled or confined and fed or maintained for a total of at least
45 days in any 12-month period, and the animal confinement areas
do not sustain crops, vegetation, forage growth, or post-harvest
residues in the normal growing season (U.S.. EPA. 1997a, 40 CFR
122.23[b]).
Animal waste from these facilities can potentially contaminate
ground water, surface soils and water, and air. Contamination
includes nitrogen and phosphorus compounds, organic, amines, fats,
and" sulf ides. Environmental concerns include ecological, human
health, and socio-economic issues {i.e., eutrophication,
biological oxygen demand, E. coli, Pfisteria pisicida, and other
microbial contaminants, carbon dioxide, ammonia, and -nitrogen
oxide releases, toxic and nuisance odors, fish kills, nitrate
drinking water contamination, particulate matter from trucking
operations, and other impacts). Region 6 has developed a
watershed based geographic information system / cumulative risk
screening methodology to assist EPA regulators in environmental
assessment and permitting of CAFO facilities through the National
Environmental Policy Act (NEPA) and the Clean Water Act (CWA) ..
The environmental assessment tool or CRIA (Cumulative Risk Index
Analysis) facilitates communication of technical and regulatory
data upon which better agency decisions can be made. The CRIA is
designed to better understand the effectiveness and results of
CAFO controls. The tool is not intended to be used alone but in
concert with other environmental program perspectives and data
(i.e., endangered species and the Fish and Wildlife Service,
state environmental agencies with cultural resources concerns).
The analysis identifies thirty-four (34) assessment parameters.
The CRIA considers environmental vulnerabilities and potential
effects of individual CAFO projects by watershed subunits. These
subunits.are called Hydrologic Unit Codes or HUCs. A watershed
subunit is created by merging watershed area data and state
stream segment information. The HUC becomes the methodology's
base analytical unit.
The scope or base area of analysis could be an entire $t*fe •
-------
few selected counties, a circle drawn around the project site, or
a.watershed. 'The CRIA methodology does not just list various
risk concerns for projects but, applies a ranking criterion to
each of the 34 environmental and industry operation concerns.
This effectively rates the parameters from desirable to less
desirable compelling EPA regulators, industry, and others
concerned with CAPO siting and operations to communicate
regarding the industries potential impact within a given
watershed or larger drainage area. The watershed level of
analysis is reasonable (ecologically based and not so
geographically large that cause, and effect relationships among
criteria are lost). The level of analysis is also consistent.
Watersheds are a common denominator for other programs, agencies,
the public. A systematic CIS analysis sums the % areas of
projects within 11-digit HUCs and scores, the projects on a-. 1-5
scale .based on a number of location specific "vulnerability"
criteria and industry imposed "impact"'criteria. A list of the
34 criteria is provided in Table 1. Specific 1-5 rankings are
provided in Appendix A (the CRIA methodology is also found on the
web at http//www. epa.gov/xp/earthlr6/enxp4a. htm) . Region 6 is
currently using the CRIA in NEPA for evaluation of swine CAFOs in
western Oklahoma. The CRIA results are documented into a NEPA
Statement of Findings for the Pig Improvement Company (U.S.EPA,
i997b) and an Environmental Assessment (EA) for Vail, Inc. (U.S.
EPA, 1998) . Region 6 hav£ used CRIA results to communicate
regulatory concerns, consistently compare CAFO operations, secure
remediation agreements, and gain assistance from industry to
conduct basic ecological research around CAFOs. The research
field tested the accuracy of CRIA evaluations for odor and
wildlife ecology (U.S.EPA, 1997), Region 6 has performed CRIA
analyses for over fifty swine CAFOs. The Region plans to expand
the methodology to cattle, chicken, and other animal agriculture
operations throughout Texas, Oklahoma, Louisiana, Arkansas, and
New Mexico.
CRIA Methodology :
Cumulative risks are identified through evaluation of: 1) Areas
of regulated and unregulated CAFOs; 2) environmental
vulnerabilities (e.g., ground water depth or soil permeability)
and; and 3) impacts from known CAFO projects (water quality,
vector/odor, wildlife habitat) specific to each watershed
subunit. Table l lists these criteria for cumulative risk
consideration.
Cumulative risk criteria are summed using a mathematical
algorithm. Key components of the algorithm are Area of known
CAFO projects (AI), Area of the Watershed Subunit (AWS), Degree
of Vulnerability (DV), and Degree of Impact (DI).
The CRIA algorithm is as follows:
CRIA = ISA / AWS] (pv) (j>r)
-------
where :
f
CRIA = Potential for significant environmental risk
A = Area of known CAFO projects
AWS = Area .of watershed subunit
DV = Degree of Vulnerability for subunit (e.g., ground
water depth, rainfall, soil permeability, populated
areas) .
DI = Degree of Impact produced by regulated CAFO
projects within the watershed subunit (e.g., animal
population density, land application, lagoon systems) .
The CRIA for swine CAFOs is calculated for each facility in a
watershed subunit area. Total areas (A) of known projects in a
watershed subunit are scored from 1 to 4 based on the percentage
of the watershed area they represent. Vulnerability and impact
factors are identified, and criteria for each were developed.
Each DV and DI criterion is scored from 1 to 5.
The calculations involve:
.1) summing the areas for known projects (A) and
determining what percent of a watershed subunit is
affected. ( [EA / AWS] X 100); these percentages are
scored on a 1 to 4 scale [no project(s) = 0 score] .
2) summing the vulnerability and impact criteria scores,
and calculating the average for DV and DI respectively;
3) .multiplying the A score by the average DV score by the
average DI score.
The maximum score possible in a watershed subunit (HUC) is 100.
The summation factor (£A) is cumulative for CAFOs in the
watershed subunit. Maximum rank for [SAI / AWS] is 4, maximum
for DV is 5, maximum score for DI is S.
CRIA = [SAI / AWS] (DV) (DI)
[4] (5) (5) = 100
Pig Improvement Company Cumulative Risk Evaluation Results
The Region 6 Cumulative Risk Index Analysis (CRIA) was used to
supplement the expanded EA's evaluation of the potent j nl f«f
-------
significant, cumulative, environmental impacts from swine CAFOs,
The CRIA considered environmental vulnerabilities and potential
effects of -individual CAFOs by watershed subunits, called
Hydrologic Unit Codes, or HUCs.
Table 1
Cumulative Risk Index Analysis (CRIA) List of Criteria
WATERSHED SUBUNIT AREA ( AI / AWS ) CRITERION
DEGREE of VULNERABILITY (DV) CRITERIA
Ground Water Probability
Rainfall
Surface Water Use
Distance to Surface Water
Population Around Facility
Other Industries, Pollution Sources, or
Protected Lands." (Quadmapper Data)
Wildlife Habitats
Soil Permeability
Ground Water Quality (Nitrate-Nitrite)
Economic (Environmental Justice)
Minority (Environmental Justice)
Surface Water Quantity
Water Quality (STORET Data)
Other CAFO Facilities
III. DEGREE Of IMPACT (DI) CRITERIA
Livestock Population Density
Lagoon Loading Rate
Treatment System Liner
Land Application Technology
Nitrogen Budget
Storage Capacity
Well Head Protection
Employment
Odor
^ Transportation
Habitat Area Effected
Density of CAFOs
Proximity of CAFOs
Phosphorus Budget
Endangered and Threatened Species
Cultural Resources
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The. following is a summary of the major findings and conclusions
from the CRIA_- version 6.0 dated January 24, 1997 (Data is
presented in Appendix A):
1) The CAFOs represent a very small percentage of the total
surface area of each HOC .(i.e., from 0.17 to 2.95 percent).
2) The lowest, individual vulnerability, average score was 2.538
and the highest was 3.077.
3) The lowest individual impact average score was 1.75 and the
highest was 2.812.
4) The lowest HUC vulnerability score was 2.538 and the highest
was 2.885.
5) The lowest HUC impact score was 1.875 and the highest was
2.398.
6) HUC 11050002040, with only the PM1 site, had the lowest area
effected (0.17%), as well as the lowest vulnerability
(2.538), impact (1.875), and total (4.759) scores.
7) HUC 11050002050, with sites Cl, C2, C3, LI, L2, L3, L4 and
Choate, had the highest area effected (2.95%), as well as
the highest vulnerability (2.885), impact (2.398), and total
(6.918) scores.
8) The HUC vulnerabilities for the CAFOs are generally high in
the areas of soil permeability, ground water quality,
surface water use, and population.
9) The HUC vulnerabilities for the CAFOs are generally moderate
to high in the areas of ground water probability, water
quality, and wildlife habitats
10) The HUC vulnerabilities for the CAFOs are generally low to
moderate in the areas of rainfall, distance to surface
water, and economics.
11) The HUC vulnerabilities for the CAFOs are generally very low
in the areas of surface water quantity, other industries,
and minorities. '
12) The adverse impacts of the CAFOs are generally very high in
the area of proximity of facilities.
13) The adverse impacts of the CAFOs are generally high in the
area of ground water well locations, density, and odor.
14) The adverse j/Hact^ of f^ GAR?S are generally moderate to
-------
high in the areas of habitat area effected, employment, arid
' livestock population density.
' *«
15). The adverse impacts of the CAFOs are generally low to
moderate in the areas of, transportation, land application
technology, and phosphorous budget.
16} The adverse impacts of the CAFOs are generally very low in
the areas of lagoon loading rate, treatment system liner,
nitrogen budget, storage capacity, endangered and threatened
species, and cultural resources. . -
On the 0 to 100 scale, the total scores are very low for all five
HUCs. This result is primarily because the area portion of the
equation scored a 1 (representing less than five percent of the
total surface acres in the HUC). This score is considered
reasonable and representative of the situation, since it is
expected that in comparison to other HUCs in the Region, the area
component should score higher. For example, in HUCs with large
concentrations of CAFOs, the area portion of the equation will
score higher since it takes only 15 percent of the HUC to be
represented by CAFOs to score a 4.
Even though the total scores for the'HUCs are relatively low, the
individual scores for a specific criterion provide meaningful
insight into potential impacts. This is also true for the
variation of scores for all sites in a criterion. Scores of 4
and 5 are important considerations at one site and multiple
sites, particularly when they relate to both vulnerability and
impact criteria. These scores (i.e., ground water1 quality, soil
permeability, density of CAFOs, proximity of CAFOs, and ground
water protection) support the conclusions in the expanded EA that
potential ground water impacts warrant monitoring. Also, high
scores (e.g., odor and habitat area effected) should be verified
through follow-up field work to improve the accuracy of the CRIA
for future use.
Discussion
The Cumulative Risk Index Analysis is designed to assess location
specific environmental vulnerabilities and CAFO industry imposed
impacts to watersheds in Region 6. The CRIA was applied to 18
swine operations owned by the Pig Improvement Company. The
facilities are located in a semi-arid, rolling grassland area of
western Oklahoma. The CRIA identified vulnerabilities of the
landscape to be permeable soils, known nitrate ground water
contamination in the watershed, and a relatively high number of
farm operations in close proximity to one another. The CRIA also
identified the ecological concern of large acres of habitat being
effected. The CRIA evaluation resulted in EPA working with the
facilities to mitigate specific concerns (i.e., protection of
playa lakes, construction of dikes and berns to protect surface
water) and to allow EPA to conduct ecological studies on the
facility property to evaluate species diversity dn^ \Qity(yb£f
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presence of odors.
References:
1. U.S. EPA, 1997a. 40 CFR 122.23 [b], Concentrated.Animal
Feeding Operations (applicable to State NPDES programs).
revised July l, 1997. Office of the Federal Register
National Archives and Records Administration, Washington,
D.C.
2. U.S. EPA, 1997b. Swick, J., G. Carney, S. Osowski.
Cumulative Risk Index Analysis (CRIA) (Swine Concentrated
Animal Feeding Operations). Version 6.0, January 24.
Enforcement Division, Region 6 Environmental Protection
Agency, Dallas, TX 75202.
3. U.S.EPA, 1997c. Swick, J. National Pollutant Discharge
Elimination System (NPDES) Statement of Findings for a
General Permit to the Pig Improvement Company (PIC) .
February 13, 1997, Region 6 EPA, Dallas, TX 75202.
4. U.S. EPA, 1998. Swick, J. National Pollutant Discharge
Elimination System (NPDES) Statement of Findings for a
General Permit to the VAL Farms. Inc. February 13, 1997,
Region 6 EPA, Dallas, TX 75202.
5. U.S.EPA, 1997d. Osowski, S. Swine confined Animal Feeding
Operation Ecological Inventory and Odor Study. Publication
No. 906-R-98-001, December 1997, Region 6 Environmental
Protection Agency, Dallas, TX 75202.
Appendix A: CRIA Data for Pig Improvement Company (PIC)
Cumulative Risk Index Analysis (CRIA)
-------
Appendix A: CRIA Data for Pig Improvement Company (PIC)
• f * ' * ' • •
Cumulative Risk Index Analysis (CRIA)
Appendix B: Facility and Area Maps
Cumulative Risk Index Analysis (CRIA) for PIG Improvement
Company PIC) . .
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CUMULATIVE RISK INDEX ANALYSIS
DEGREE OF VULNERABILITY SCORES
PIC USA, COCHINO RANCH LLC, AND MAJOR FARMS
GWP
Rf
SWU
DSW
PAF Ol
WH
SP
GWQ
EEI
MEJ SWQ WQ
a
a
CJ
i.i
U
U
L4
LS
L6
Kronswlcrb-f
Krarvseder n -f
PMI
PM2
PM3
PM4
CM I
CM2
CM 3
30.2%
0.0%
8.2%
1.7%
12.2%
34.2%
21.1%
2.8%
0.0%
0.0%
0.8%
0.8%
3.1%
n.o%
0.0%
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9.1%
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5
1
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27.46
27.46
27.46
27,46
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7206
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4093
11832
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12358
9665
11575
8934
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3
2
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95
94
76
58
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64
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82
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144
95
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4
5
3
5
5
4
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4
3
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0
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0
0
0
0
0
0
0
a
0
0
0
0
a
0
0
0
0
32.1%
32.1%
32,1V,
32.1%
32.1%
32.1%
32.1%
12.1%
2tV)%
26.7%
31.7%
31.7%
58.1%
49.7%
49.7%
49.7%
49.7%
49.7%
49.7%
3
3
3
3
3
3
3
3
2
2
3
3
3
4
4
4
4
4
4
<20%
22.9%
<20%
93.4%
<20%
<20%
<20%
86,3%
95.7%
104.0%
<2tt%
<20%
38.0%
21.4%
<20%
20.7%
<2fl%
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<20%
3
5
4
3
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4
5
5
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4
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5.4
5.4
5.4
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5.4
5.4
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7.2
7.2
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43.0%
43.8%
41.7%
22.8%
47,2%
44.1%
39.2%
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18.8%
15.2%
11.6%
45.1%
36.0%
37.0%
33,8%
45.3%
3
3
2
1
3
3
2
3
2
2
2
3
11.8%
8.0%
9.8%
3.4%,
9.R%
10.8%
9.9%
8.9%
2.6%
1.3%
2.9%
2.9%
0.0%
9.3%
1.8%
6,154
0.7%
7.3%
4.8%
•
0.6
0.6
'0.6
0.6
a.
-------
CUMULATIVE RISK INDEX ANALYSIS
r SCREE OF IMPACT SCORES
PIC US A, CO HINO RANCH LLC, AND MAJOR FARMS
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21.1
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20.7
21.7
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2
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-------
Confined Animal
Feeding Operations
rn Waterahad
A? Mflfor Road
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-------
Confined Animal
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-------
Cumulative Risk Assessment Practicum
Case Study Draft
Pentachlorophenol (PCP)
(A Heavy Duty Wood Preservative (HDWP))
OPP
Prepared for Practicum
November 12-13,1998
-------
July 08, 1998
Cumulative Risk Assessment
Planning and Scoping Document For
Pentachlorophenol (PCP)
A Heavy Duty Wood Preservative (HDWP)
I. Background
U.S. EPA's Office of Pesticide Programs (OPP), as required by the Federal Insecticide, Fungicide, and
Rodentieide Act (FIFRA), and amended by the Food Quality Protection Act (FQPA) of 1996, institutes
procedures for the registration and reregistration of pesticides. OPP's Antimicrobials Division (AD)
has regulatory management over antimicrobial pesticides, including certain wood preservative
pesticides such as Pentachlorophenol (PCP). AD is currently responsible for generating Reregistration
Eligibility Decision documents (RED's) for three wood preservatives (PCP, Chromated Copper
Arsenicals (CCA), and Creosote). These documents will reassess the potential risks these chemicals
may have on human health and the environment. All three RED's are slated for release in FY 1999.
Note that as part of the reassessment of the wood preservative chemicals NAFTA harmonization efforts
are underway between USEPA and Health Canada's Pest Management Regulatory Agency (PMRA).
Since late FY 1997, AD's science and regulatory managers have dedicated staff resources within the
division to accomplish the goal of preparing and issuing the PCP RED, AD formed a PCP RED Team
charged with generating the draft RED document by the end of FY 1998. Designated staff leads from
each science discipline, and regulatory managers prepared a "Workplan" which identified datagaps,
created a timeline for completion of the RED, and identified steps to be taken by each discipline in
order to expedite the work. Science staff from AD and PMRA are collaborating on data sharing and in
conducting joint data reviews hi compliance with NAFTA.
Since the PCP RED will be the first RED document to be issued by OPP's newly formed AD, the
division welcomes the opportunity to participate in the "Planning and Scoping" exercise for ORD's
Cumulative Risk Assessment Workshop. Involvement will foster dialogue with other Agency program
offices and enable AD to develop a risk assessment process that is as comprehensive and valid as
possible.
II. Regulatory History
A. Regulation Under FIFRA/FOPA
* Pentachlorophenol (PCP) was first registered in the United States in 1948 as an active
ingredient.
* In 1978 USEPA issued a Federal Register Notice initiating an administrative process to
consider whether pesticide registrations for wood preservative chemicals should be cancelled or
modified due to adverse toxicological effects noted in animal toxicity studies. The Agency
issued notices of "Rebuttable Presumption Against Registration" (RPAR) for PCP based on
teratogenicity and fetotoxicity findings. In addition, the Agency determined that PCP use
posed the risk of oncogenicity due to the presence of microcontaminants (dioxins/furans/HCB).
The Agency subsequently published Position Documents to address comments made by
-------
stakeholders on the Federal Register Notice. The conclusion of the RPAR process in 1984 and
final settlement agreements with stakeholders in 1986 restricted PCP uses and modified its
terms and conditions of registration.
* Banned uses of PCP included treatments to wood used for food contact surfaces/containers, log
homes, and structures housing livestock which are farrowing, brooding, and/or cribbing.
* The RPAR process also resulted in cancellation in 1987 of certain non-wood preservative uses
of PCP as a herbicide, defoliant, mossicide, and mushroom house biecide. In 1993 uses of
PCP were terminated as a biocide in pulp and papermills, oil wells, and cooling towers.
* In August, 1996, the Food Quality Protection Act (FQPA) was passed. FIFRA, as amended by
FQPA, now requires EPA to examine pesticide uses relative to the potential aggregate and
cumulative exposures and risks for the general population and for sensitive subpopulations
(children and infants). Aggregate exposures/risks represent the multiple exposures/risks from
uses of a single chemical (e.g., exposures/risks from the diet, drinking water, or other
sources). Cumulative exposures/risks represent the multiple exposures/risks from uses of
multiple chemicals sharing a presumed common mechanism of toxiciry. For wood
preservatives such as PCP, the Agency must now address aggregate and cumulative exposures
and risks.
B. Regulation Under Other Acts
PCP is also regulated under other Acts including: Clean Water Act, Safe Drinking Water Act, Clean
Air Act, and Resource Conservation and Recovery Act. Attachment B outlines the major points of
regulation under these Acts.
HI. PCP Use Profile
* PCP is an organic chemical formed by the high temperature chlorination of phenol. These high
temperatures result in the formation of microcontaminants (dioxins/furans/HCB).
* PCP is an oil-borne pesticide first registered in the United States in 1948 as a preservative of
wood (seasoned/unseasoned) to prevent decay from fungal organisms and insect damage. It is
commercially available in various forms, including: as a solid crystalline block, soluble
concentrate (solid/liquid), and ready-to-use (grease/liquid).
* Vulcan Chemicals, division of Vulcan Materials Company, and KMG-Bemuth, Inc. are the
primary producers of the PCP technical chemical for the Unites States and Canadian markets.
These companies are considered the primary stakeholders.
* PCP product labeling and Label Use Information System (LUIS) Reports generated by
OPP/BEAD were used as primary sources to confirm PCP use patterns.
* Meetings with stakeholders on The Penta Task Force further clarified banned and current use
practices and identified some minor specialty use applications. (See Attachment A for an
overview of PCP use patterns.)
-------
* Currently j 25 PCP products remain registered as wood preservatives in above and below
. ground wood protection treatments and for treating wood for aquatic/marine environments. All
25 products are Restricted Use pesticides: 22 are End-Use Products for commercial use, and 3
•are TechnicaTGrade Products for manufacturing use. (Health Canada's PMRA has regulatory
purview over three (3) Technical Grade Products.' There are no End-Use Products registered
in Canada.)
* Utility poles and crossarms represent 92.5 % of all uses for PCP-treated lumber. Secondary
uses for PCP include the treatment of railroad crossties, wooden«pilings, fence posts, and
lumber/timber used for the construction of commercial/residential structures (e.g., patios,
decks, walkways, and fences).
* There are various types of PCP wood preservation treatments including: pressure/noh-pressure
treatments to seasoned and unseasoned wood, and remedial treatments to wood previously
treated with PCP. Commercial treatment of lumber, such as telephone poles, usually involves
a pressure treatment process hi which wood is pushed into long cylinders (retorts) that are
pressurized in the presence of PCP. Non-pressure treatment processes also exist such as
thermal treatment (wood soaked in hot/cold baths), dip treatment, and extended soaking of
wood in open vats. Remedial treatments are primarily groundline wood surface treatments
(brush-on, sponge-on/swabbing, spraying, low pressure injection, or bandage-wrap) to
standing utility poles and other standing timbers to extend then* service life.
f
IV. Hazards. Exposure and Risk Dimensions
A. Hazard Identification
1. Hazards - Human Health
The Agency and PMRA are examining the full range of data, submitted by the registrants) or available
in the scientific literature, for both the active ingredients and contaminants of concern. Such data
include: acute toxicity, developmental/reproductive effects, chronic effects, carcinogenicity, and
endocrine effects. Also, if epidemiological studies or pesticide incident data are available for PCP, the
Agency will examine these as well.
As a summary, AD presents the following:
* PCP has been associated with both acute and chronic (non cancer) adverse health effects,
primarily related to liver toxicity. Also, EPA's weight of evidence carcinogenicity
classification for PCP is B2, probable human carcinogen. PCP is known to contain
polychlorinated dibenzo(p)dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) as
contaminants. The toxicity of PCDD/PCDF congeners are typically expressed, based on the
comparison of their toxicity to the most toxic congener (2,3,7,8-tetrachlorinated
dibenzo(p)dioxin; 2,3,7,8-TCDD), using Toxicity Equivalency Factors (TEFs). Toxic
Equivalency values (TEQs) are calculated as the sum of the products of individual congener
concentrations and their respective TEF. EPA has set regulatory limits on the concentrations of
certain PCDD/PCDF congeners in PCP.
-------
* Available scientific literature confirms that PGP targets the liver, kidneys and central nervous
. system and has been linked to cancers {e.g., acute leukemias, lymphomas, and multiple
myelomas). Data suggest PCP damages the nervous, immune, and reproductive systems
(including elidocrine disruption)-. PCP is readily absorbed by lungs, skin, and stomach. While
much of PCP is excreted in the urine, it does accumulate in tissues, particularly muscle, bone
marrow and fat. '' •
2. Hazards - Environmental
The Agency and PMRA are examining the full range of data, submitted by the registrants) or available
in the scientific literature, for both the active ingredients and contaminants of concern. Such data
include: acute toxicity, subacute effects, chronic effects, and endocrine effects. Also, if pesticide
incident data are available for PCP, the Agency will examine these as well.
As a summary, AD presents the following:
* Available scientific literature confirms that PCP bioaccumulates in mammalian and fish tissue
and laboratory data indicate there is a very high toxicity of PCP .to fish on an acute and chronic
basis. Data submitted by the registrants to the Agency suggest that PCP is moderately to
slightly toxic to avian species (mallards and bobwhite quail) on an acute oral basis. Subacute
dietary tests indicate that it is practically nontoxic to avian species. •
3. Hazards - Microcontaminants
The hazards of the microcontaminants are an important part of the human and environmental hazards
identification process. AD plans to utilize data compiled by the Office of Research and Development
(ORD), the lead office for dioxin issues. AD believes that there are likely more data available to
identify human health hazards than to identify environmental hazards. Therefore, the environmental
hazards identification process may be highly qualitative.
B. Exposure Scenarios
Canada's PMRA will focus on all exposure aspects of PCP: i.e., a "cradle-to-grave" approach which
addresses manufacture, wood preservation, utility poles in service, and removal/disposal of utility poles
from service to disposal sites (e.g., landfills). However, AD/OPP (because of overlapping Agency
statutes) will focus its exposure assessments as follows: (1) human exposure assessments will address
occupational, or wood preservation, sites where the greatest human exposures are likely to occur; and
(2) environmental exposure assessments will focus on in-service, treated utility poles, since these
provide potentially for emissions of PCP and/or microcontaminants into the terrestrial and/or aquatic
environments.
1. Exposures - Human Health
AD will examine application and post-application exposures for both occupational and residential
settings. AD's focus will be on occupational settings (primarily, wood treatment plants) where the
exposures for mixers, loaders, applicators as well as utility pole workers must be evaluated. However,
AD plans to address aggregate and cumulative exposures since utility poles are found, and can receive
-------
remedial grqundline treatments of PCP, in residential settings. Specifically, the following points should
be noted:
f •.
* Human exposure assessments will focus primarily on workers handling PCP
formulations and/or PCP-treated wood. Exposure levels and the dernial/inhalation
routes of- exposure will be of primary concern. AD will assess exposures to primary
handlers who mixAoad/apply concentrates to treat wood in treatment facilities. The
assessment on secondary handlers will include addressing utility pole installers and
repair workers. -AD anticipates;that,the most significant potential exposures*wUkoccur
at the wood treatment plants during pressure/non-pressure applications and post-
. application handling; followed by the exposure potential to utility workers engaged in
pole installation and remedial groundline treatments to utility poles.
:
* Human exposure to PCP may occur in occupational settings or among the general
population primarily via dermal and inhalation routes. Ingestion of PCP can also
occur indirectly through hand-to-mouth transfer after dermal contact. Workers may be
exposed through inhalation of PCP-contaminated air in the workplace or by dermal
absorption during handling of the PCP formulations or PCP-treated materials.
Virtually all workers exposed to airborne concentrations take up PCP through the lungs
and skin. Exposure may occur during mixing and loading of PCP into the tanks,
loading and unloading the retort, and during maintenance operations. General
population exposure may occur through dermal contact with PCP-treated products or
contaminated soils, or ingestion of food, soil, or groundwater that has been
contaminated from historical uses (i.e., uses now banned under the 1986 RPAR
proceedings). General population exposure (i.e., inhalation of contaminated indoor air
or dermal contact with treated areas) may also occur among individuals residing in
older buildings constructed of PCP-treated wood products.(i.e., log homes).
* In 1991, as an outcome of the Agency's RPAR proceedings, USEPA required registrants of
PGP-based technical source and end-use products to submit certain applicator exposure
monitoring data. These data requirements were designed to estimate the potential dermal and
inhalation exposures associated with PCP wood preservative uses (i.e., occupational, at
application, exposures). However, the Agency did not require post-application exposure data
since the occupational (at application) exposure scenarios are expected to be the scenarios with
highest human exposure.
* Following 1991, an industry consortium, headed by Vulcan Chemical, formed the Penta Task
Force to address the Agency's reregistration requirements for human exposure data. In 1993
five human exposure studies submitted by the Task Force were deemed unacceptable upon
Agency review. These studies had been conducted to evaluate occupational and general
population exposures/risks from existing and historical uses of PCP. However, these studies
did not provide empirical human exposure data which could be used by the Agency. Thus,
limited human exposure monitoring data, which are acceptable for use in the reregistration
assessment of all three wood preservative chemicals, are available.
* Present efforts: (1) AD is working with contractor personnel to identify all potential
application and post application use scenarios at occupational and residential settings. For
-------
6
' •*
occupational scenarios, a data matrix table has been drafted of the potential levels of exposure
associated" with certain typical work tasks. However, the residential use scenario component
has not yet been drafted for incorporation into this table. Therefore, AD has not finalized how
it will approach aggregate and cumulative exposures for residential scenarios; (2) information
regarding AD's choice of occupational/residential use scenarios has been shared with PMRA's
human exposure assessors. PMRA will conduct a peer review of the completed draft version
' of the Agency's Human Exposure Science Chapter for the PCP RED in early FY 1999; and (3)
recent dialogue with the Penta Task Force has yielded a commitment to conduct an
occupational exposure study of treatment plant workers using air sampling pumps to estimate
inhalation exposure, and biological monitoring techniques (urine analysis instead of dermal
exposure dosimetry testing) to estimate the absorbed dose. This worker exposure study will
monitor all application and post-application work tasks associated with PCP wood treatments.
However, this study is not likely to be completed until FY 2000, after issuance of the PCP
RED. . '
2. Exposures - Environmental
For PCP, AD believes the primary routes of environmental exposure are water and soil via leaching
from utility poles, railway ties, pilings, piers, docks, etc. The most likely environmental compartment
to be exposed to PCP is the aquatic. AD will characterize risks using these environmental scenarios.
AD will not examine environmental risks from the following scenarios becuase they are regulated
under other statutes: manufacture of PCP, use of PCP in wood preservation plants, and disposal of
treated lumber in landfills or as hazardous waste.
3. Environmental Fate Chemistry
AD believes that environmental fate chemistry is a key component of both the human and
environmental exposure (and risk) assessments for PCP and microcontaminants. For PCP AD has
compiled pertinent data from the registrant and literature sources and believes that the fate and
degradation of PCP are well understood (see Attachment C). However, for the microcontaminants AD
will be working with a contractor and ORD to determine if adequate environmental fate and emissions
data can be compiled for dioxins and furans relative to the wood preservation sector. Of particular
interest are emissions from in-service utility poles; if inadequate emissions data exist, then AD plans to
use modeling (see 4 below).
4. Exposures - Modeling
s
Because of the apparent lack of monitoring and/or emissions data for PCP (and/or microcontaminants)
for various use scenarios, but particularly for in-service utility poles, AD will utilize models, such as
the fugaciry model, to estimate concentrations of PCP and/or microcontaminants in the environment.
Fugacity models identify the percentage distribution of a chemical (e.g., PCP) in various compartments
at equilibrium and the proportion of loss through advection and reaction from each compartment. Such
models typically utilize three levels of estimates, but AD may also use other models that appear to be
appropriate. Also, AD will need to work closely with ORD concerning any emissions estimates the
division may develop for the microcontaminants.
C. Risk Characterizations
-------
1- Human Risks .... •
*
*
For the Agency to conduct a thorough human risk characterization, data are needed on: (1) the
toxicity/effects of the pesticide, (2) the pesticide's use patterns, and (3) human exposure scenarios.' To
date, AD has compiled extensive information for (1) and (2), but is utilizing surrogate data for (3) as
well as requiring an occupational exposure study of treatment plant workers. (However, this study is
not likely to be completed until FY 2000.)
As discussed .earlier, AD's focus will be on characterizing the occupational risks of PCP: the risks
(application) for mixers/loaders/applicators who prepare or apply PCP to wood and the risks (post-
application) for workers handling treated wood products (e.g., utility pole installers, repair workers).
However, with passage of FQPA in 1996, AD now must characterize the potential risks associated with
non-occupational, or residential, use scenarios. For these AD is planning to assess the aggregate
(dietary, drinking water, other) and cumulative risks for PCP that may be associated with-any
residential use scenarios.1 Further, we plan to assess the potential risks of PCP to sensitive
subpopulations such as children and infants as well as any potential endocrine effects.
For both the occupational and residential risk assessments AD will compare available toxicological
hazard data, use pattern information, and exposure data. As an example, Margins of Exposure
(MOE's) will be calculated for occupational workers to determine the potential risks of workers
exposed to PCP under various occupational use patterns. Also, Because of PCP's carcinogenic
potential, the cancer risks will be calculated using the Lifetime Average Daily Dose (LADD) and the
Cancer Slope Factor. For residential use patterns similar approaches may be taken also.
2. Environmental Risks
Environmental risk assessments are required under FIFRA to estimate the likelihood or probability mat
adverse effects (e.g., mortality to single species of organisms, reductions in populations of nontarget
organisms due to acute, chronic and reproductive effects, or disruption in community and ecosystem
level functions) will occur, are occurring, or have occurred on wildlife and aquatic organisms. Data
developed and submitted are used by the Agency for determining potential hazards to nontarget birds,
wild mammals, fish, plants, and aquatic invertebrates.
In an environmental risk assessment, toxicological hazard data and exposure data are compared using
regulatory risk criteria. Typically the toxicological hazard data may consist of acute LD50 and LC50
values, or chronic no-effect-levels (NOEL's) for the most sensitive indicator species. Exposure data
normally consist of model-based Estimated Environmental Concentrations (EEC's) in important media
of concern (i.e., water, soil, nontarget organism food items) plus a profile of the nontarget organisms at
risk. A Risk Quotient (RQ) is determined by dividing the exposure data (EEC) by the toxicology data
(LD50, LC50, etc.). A comparison is then made between the RQ and an Agency Level of Concern
1 Aggregate risks: risks associated with multiple pathways
of exposure for a single chemical; cumulative risks: risks
associated with multiple pathways of exposure for multiple
chemicals that share a presumed common mechanism of toxicity.
-------
. 8
(LOG) to determine if there is a potential risk to nontarget organisms.
% i
For PCP, the primary routes of-exposure are water and soil via leaching from utility poles, railway
ties, pilings, piers, docks, etc.. The most likely environmental compartment to be exposed to PCP is
the aquatic. Available scientific literature confirms that PCP bioaccumulates m mammalian and fish
tissue and laboratory data indicates there is a very high toxicity of PCP to fish on an acute and chronic
basis. Data submitted by the registrants to the Agency suggest that PCP is moderately to slightly toxic
to avian species (mallards and bobwhite quail) on an acute oral basis. Subacute dietary tests indicate
that it is practically nontoxic to avian species.
*
3. Risks from Microcontaminants
Considering the lack of pertinent emissions data for dioxins/furans for the wood preserving industry
sector, AD's human and environmental risk characterizations for PCP microcontaminants is likely to be
highly qualitative. However, AD recognizes that the risks of the microcontaminants are an important
part of the risk characterization process. AD plans to work closely with a contractor and ORD, the
lead office for dioxih issues, in an'effort to develop human and environmental risk assessments.
4. Comparative Risk Analysis
Upon completion of the human and environmental risk assessments, AD plans to follow similar steps
for evaluating creosote and CCA, two alternative HDWPs, Once all three risk evaluations are finalized
then AD will perform a comparative risk analysis of the three compounds (PCP, creosote, and CCA) to
determine how the human and environmental risks* associated with similar use patterns, compare.
V- Assumptions. Uncertainties, and Limitations With Risk Characterizations
AD recognizes a variety of assumptions, uncertainties, and limitations exist with the proposed human
and environmental risk characterizations. Some of these are:
A. Human Risk Characterization
* It is assumed that the occupational exposure study sponsored by the Penta Task Force will
provide risk assessors with valuable data needed for the human exposure risk assessment.
Since these data will not be available until FY 2000, the human exposure assessment will need
to rely on surrogate data and may fall short of its goal to accurately determine exposure risks to
workers.
* The acceptability of biomonitoring data over dermal (passive dosimetry) monitoring data has
been questioned. Although the pharmacokinetics of PCP are well known, certain reservations
remain regarding test participant compliance in generating urine samples. Dermal monitoring
was rejected as an option due to workers overheating while wearing the test garments (whole
body dosimeters) in a pilot study.
* The required worker exposure field study will not analyze air and urine samples for the PCP
microcontaminants (dioxins/furans/HCB), only for the presence of PCP and its metabolites.
-------
* The default assumptions, based on surrogate data, used by the risk assessors might not reflect
. real-use conditions, thereby weakening human exposure risk characterizations. :
*• AD's assessment will not include evaluation of risk concerns for PCP uses "banned" under the
RPAR proceedings (e.g., risks to occupants of log homes).
* AD's assessment will not include estimations of potential human exposure risks from contact
with PCP-treated wood used for minor specialty applications (e.g., uses in bridges, trusses,
architectural restoration), only typical exposure scenarios will be evaluated.
* AD will assume that any existing uses for PCP-treated lumber in groundline contact "interior"
building components pose limited human exposure concerns since the 1986 RPAR settlement
requires 2 coats of an appropriate sealant be used on all interior wood surfaces.
B. Environmental Risk Characterization
* The Agency does not typically require data on small mammals and does not look at the effects
on small mammalian wildlife (voles, mice, bats, etc.). Data is extrapolated from the human
toxicology rat studies to be utilized in determining effects on wildlife mammals. This area is of
importance because small mammalian wildlife feed on terrestrial invertebrates (insects,
earthworms, etc.) and/or plants that may have been exposed to the pesticide. AD is uncertain
what effects are occurring in the food chain.
* Canada uses data regarding subchronic exposure of bats to treated timbers used for bridge
trusses. Scientific literature documents the lethal effects on bats nesting on bridge trusses
newly treated with PCP. The Agency will note this information in their RED, however no
further studies will be requested to further investigate the potential hazards to this mammalian
population.
* The Agency will not be conducting any field studies on the effects of PCP on terrestrial
invertebrates such as earthworms. Canada and Europe do incorporate data collected in this
area.
* There is no consensus on reproducible laboratory testing to determine the levels of PCP leached
from the wood. To date the levels leached into the environment are unknown. This is true for
PCP and its microcontaminants,-furans, dioxins, and HCB.
* The environmental risk characterization is focused on the effects on individual organisms as
opposed to populations of organisms. AD's environmental risk assessment's weakness is that
mesocosms and population effects are not assessed on a routine basis.
* USEPA's ORD will generate a final version of a Dioxin Source Inventory Report for release in
late fall of 1998. It is assumed that this report will benefit risk assessors in making quantitative
determininations of dioxin releases for use in the environmental exposure assessments.
VI. Stakeholder Input
-------
10
AD has actively involved stakeholder input in the human and exposure/risk characterization processes.
In addition, (1) the review of the HDWPs is a NAFTA project in which Canada and IjSEPA are
working closely together; and (2) AD will need to work closely with other Agency offices such as
ORD. Stakeholders who are involved in the review process consist of: industry consortiums (e.g. PCP
Task Force), PCP chemical manufacturers, PCP end-use product manufacturers, end-users of PCP
products, and end-users of PCP-treated wood.
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Attachment A: PCP Use Patterns
Banned Uses;
^
* Log Homes
* Chairs/Outdoor Furniture ' -
(Bare Treated Wood)
* Residential/Industrial/Commercial Interiors
(General Use)
* Farm Building Interiors (Direct Contact with Domestic/Livestock Animals which Crib(bite) or Lick the
Wood.)
* Farm Building Interiors (Direct Contact with Animal Farrowing or Brooding Facilities.)
* Farm Structures/Containers for Storing Silage or Food. (Human Food/Animal Feed Contact.)
* Cutting Boards/Countertops
Allowed Uses:
* Utility Poles/Crossanns
Crossties
Single Pole Structures (Radio Towers)
Bridges
Trusses (Glue laminates e.g. Swimming Pool Trusses)
Timbers
Posts
Pilings/Piers/Docks
Lumber
Fencing
Porches
Shingles
Steps
Architercural Restoration (Outdoor Tongue .& Groove Flooring)
Patios/Decks/Walkways
* Chairs/Outdoor Furniture
(ONLY if 2 Coats Sealant Applied )
* Residential/Industrial/Commercial Interiors
(Laminated Beams or Groundline Contact Building Components.
Both Uses Allowed if 2 Coats of Sealant Applied.)
* Farm Building Interiors (Where Domestic/Livestock Animals DO NOT Crib(bite) or Lick the Wood.
Groundline Contact Building Components Use Allowed if 2 Coats of Sealant Applied.)
Diminished Uses: Joinery/Millworking (No Evidence of Treated Products being Marketed.)
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Attachment B: PCP Regulation Under Other Acts
Regulation of PCP under the Clean Water and Safe Drinking Water Acts
*- . *
* . PCP is designated hazardous substance under the CWA (40 C.F.R. pt 116)..
* PCP is a designated toxic pollutant under the CWA and is subject to effluent limitations resulting from
application of best available technology '(BAT) that is economically achievable. New source.emitting PCP
also must meet stringent new source performance and pretreatment standards (40 C.F.R. §§ 401.15,
403.55).
«•••;'!. ''i
* EPA has set a contaminant level of 0.001 mg/L for PCP in drinking water; granular activated carbon is
BAT for achieving compliance with this standard (40 C.FJEL §§ 14131 (3) (46), 141.50 (a) (15)).
•* Under federal water quality guidance for the great lakes system, PCP is subject to acute- and chronic-based
water quality criteria for the protection of aquatic life in ambient water (40 C.F.R. § 132.6).
Regulation of PCP under the Clean Air Act
* PCP is designated Hazard Air Pollutant (HAP) under section 112 of the CAA. Major sources emitting PCP
are subject to stringent Maximum Achievable Control Technology (MACT) emissions standards (42
U.S.C. §§ 7412(b), (d)). PCP wood preserving sites are not a major source for purpose of the MACT
standards.
* Units at major sources that manufacture PCP are subject to National Emission Standards for organic HAPs
for the Synthetic Organic Chemical Manufacturing Industry (40 C.F.R. pt 63 subst F).
* . National emission standards apply to off-site Waste and Recovery Operation if, in part, the material being
handled contains PCP (40 C.F.R. pL 63 subst. DD).
Regulation of PCP under RCRA
* Certain PCP containing waste are listed as acutely hazardous (40 C.F.R. § 261.31).
* PCP wood preserving wastes are identified as toxic (40 C.F.R. pt 261 subst D)
* PCP wastes are prohibited from land disposal under EPA's land disposal regulations, unless universal
treatment for such wastes are met (40 C.F.R. §§ 268.30,268.40).
* PCP is subject to groundwater assessment monitoring requirements applicable to municipal solid waste
landfills and to owners/ operators of hazardous waste treatment/storage/disposal facilities (40 C.F.R. pts.
258,264).
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Attachment C; Pentachlorophenot (PCP) .
Environmental Fate Studies and Assessment
•i •*.
Abiotic degradation of PCP
PCP does not hydrolyze in acidic, neutral or basic conditions and can therefore be a persistent molecule
.in abiotic aqueous conditions. It, however, photodecomposes under uv.light in water quickly with a half-
life of 3.5 hours at pH 7.3 and 100 hours at pH 3.3. Some of the, identifiable degradates are:
tetrachlorocathecol, tetrachlororesorcinol, tetrachlorohydroquinone, chloranil, hydroxyquinones, 2,3
dichloromaleic acid which slowly decompose to carbon dioxide., chloride ion and other organic
fragments which are hard to identify. In the vapor phase^PCP is moderately stable with a
photodegradation half-life of about 37 days under simulated sunlight 2,3,5,6-tetrachlorphenol was
identified as a major photoproduct. PCP showed no photolytic breakdown tendency on soil surface • .
(sandy loam soil) under dark conditions. However, in the presence of light, it is moderately stable with
an estimated half-life of about 3 8 days.
Biotic degradation of PCP
PCP metabolizes rapidly under aerobic aquatic conditions and has a half-life of less than five days.
Under anaerobic conditions, it metabolizes a little more slowly with a half-life of about 34 days. (These
results were obtained with blue sandy loam soil.) It is therefore not a persistent substance in natural
waters. Under dark but aerobic conditions, soil (sandy loam) metabolizes PCP slowly with a half-life of
63 days. Tri and tetrachlorophenols were identified as degradates. Adsorption/desorption studies on
four soils (Georgia sandy loam, Ohio Clay loam, California sandy loam and Nebraska Blue sandy loam)
showed that PCP binds moderately to strongly to the soils. KQC values revealed that PCP soil binding is
tight with Georgia, Ohio and Nebraska sands and moderately so with the California sand. Thus, PCP has
a great tendency to attach to the organic content of sediments (high KQC) and is found to bind more
strongly in acidic soils but is mobile in neutral to basic conditions. Based on these data it appears PCP
could be transported to surface waters and potentially could be found in drinking water.
Bioaccumulation studies
Bioaccumulation studies with bluegill sunfish revealed that when exposed to 2.5 ug/L PCP for 28 days,
the Bioconcentration Factors (BCF) were 190X, 740X and 490X for edible tissue, non-edible tissue and
whole body tissue, respectively. Depuration for the whole body was one day, and 98% is depurated
within fourteen days. No metabolites were found in these studies.
Leaching Studies
One study on three Southern pine poles soaked with PCP was conducted. Poles were exposed to
different solutions: unbuffered water, buffered water at pH 5, 7 and 9, sea water, sea water in 0.1 ON
HC1, and 0.10N HC1. The average leach rate varied between 1.76x10-* to 6.33x10° mg PCP/kg
leachate/in2 surface area/day. Leaching peaks in one day for most of the solutions except the solution at
pH 9 for which leaching peaked in 3 days.
-------
Cumulative Risk Assessment Practicum
Case Study Draft
Chicago Cumulative Risk Initiative
Region V and OPPT
Prepared for Practicum
November 12-13,1998
-------
DRAFT
Summary of Purpose, Scope, and Technical Approach:
Evaluating Cumulative Risks in the Chicago Metropolitan Area
1. INTRODUCTION
The following is a summary of the overall purpose, general scope, and technical approach
for the study, "Evaluating Cumulative Risks in the Chicago Metropolitan Area" (the CCRI Phase
III risk assessment). The approach is a synthesis of the direction and information that was provided
during meetings with stakeholders (petitioners, EPA Region V senior managers, and other state, and
local government representatives) in December 1997 and April 1998. As such, this summary does
not reflect any one viewpoint, but attempts to balance various needs and concerns with products that
are technically feasible. It also attempts to incorporate major concepts suggested by the Petitioners
j
in their strawman proposal and matrix, while following EPA's Cumulative Risk Assessment
Guidance on Phase I Planning and Scoping.
The three major study components will be an overview of health indicators, a cumulative risk
evaluation for multiple point sources, and a description of other risk pathways. These will be
integrated to produce a comprehensive risk assessment that allows comparison of contributions
among sources and of risk levels among subareas of the study region. In October 1997, Argonne
National Laboratory produced a Concept Paper in which various conceptual approaches for
cumulative risk assessment were evaluated. The approach outlined in this summary is essentially
the source/receptor hybrid model described in the Concept Paper. Within this approach, the majority
of effort will be placed on evaluating the contributions to exposure and risk within study areas from
multiple point sources of emissions to ambient ah* (Section 3.2 below).
Cumulative risk means different things to different people. A general definition is the total
health risk associated with multiple stressors from multiple sources. EPA risk assessments have
typically addressed the incremental risks (above background) of all chemicals emitted in significant
quantities from a single facility. Although a total measure of cumulative carcinogenic or toxic risk
for all possible exposures is not currently possible, this study will provide a learning process for
evaluating some additional aspects of cumulative risk in the permitting process. This summary
presents general direction; the specifics may change to reflect technical feasibility. Where data
inadequacies prevent full development of the proposed scope, the scope will be limited.
-------
2. GOALS
• v,
The overall puipose of this study is to refine and demonstrate methodologies for assessing
children's environmental health risks (both carcinogenic and noncarcinogenic) due to the
accumulation of multiple stressors from multiple sources that impact a specific area. A basis will
be developed for comparing risks in study areas to reference areas or baseline levels. Specific
objectives are to:
a. conduct a cumulative risk analysis that specifically addresses concerns of the Agency and
Stakeholders, including identification of health-compromised subpopulations of children and
. •.
of locales with elevated hazard levels;
h. illustrate implementation of the Administrator's Cumulative Risk Guidance;
c. take the initial steps in developing the basis for transferring a cumulative risk methodology
to other units in the Agency.
3. SCOPE
This section describes the general scope of the assessment and provides an overview of the
technical approach that will be used. Research on health indicators (Section 3.1) will address the
goal of identifying sensitive subpopulations of children. The data produced from the cumulative risk
evaluation for multiple air sources (Sections 3.2) will quantify the risks from air contaminants in
specific areas, and the description of other risk pathways (Section 3.3) will help to identify other
sources of risk. All the above information will be utilized in the risk integration portion of the study
(Section 3.4) to gain insight into reducing risks to children. The following list is a summary of
elements that apply to the entire cumulative risk study:
- Risk dimensions: Multiple health endpoints (health effects), multiple stressors, and multiple
sources will be assessed.
- Stressors: The scope will be restricted to environmental contaminants, with a focus on releases
due to human activity. The assessment will include the chemicals that are most important,
given the locales and sources, selected as the focus of study. The selection of chemicals will
be constrained by data availability
- Sources: The emphasis will be on EPA-regulated/permitted sources, with other important
source categories added as needed to develop a more complete risk management perspective.
- Geographic Area: The study region will cover Cook and Lake Counties. Within that area, two
to four locales will be selected for more detailed study.
- Population: The focus will be on children, from conception through age 17, with assessment
of lifetime exposures where appropriate. Particular attention will be given to risk evaluation
for health-compromised children (e.g., asthmatic, lead poisoned, etc.) where possible.
-------
The following subsections provide additional information on the technical elements that
apply specifically to each task, including assumptions, constraints, implications, and^atalimitations.
« • ..
3.1 Health Indicators (Task 1) .
The availability of data related to children's environmental health status will be investigated
for lead poisoning, asthma incidence, and cancer incidence and mortality. If these .data permit
identification of locales with elevated rates, this information.will be one of the factors considered
in selecting study areas. Specific health conditions which lead to increased sensitivity (or
susceptibility) to environmental pollutants among children may also be included if data are available.
For instance, data on prevalence of sickle cell anemia in children within various locales may be of
interest. Where data related to a particular issue are absent or lack geographic relevance, further
exploration of that issue will be precluded.
3.2 Cumulative Risk Evaluation for Multiple Emission Point Sources (Task 2)
This effort will focus on evaluating the contributions to exposure and risk within the study
areas from multiple point sources of emissions to ambient air. To provide a basis for comparing the
study areas to the rest of the Cook and Lake County area, screening-level estimates of ambient ah*
risks from major source categories and background will be developed for all Census tracts. To
develop comprehensive ambient air risk estimates for the study areas, appropriate portions of the
detailed modeling and the screening level modeling results will be combined.. The task will have
three components:
Task 2a: Exposure and risk from multiple EPA-regulated point sources within two or more
(up to four) discrete study locales will be evaluated. Possible factors for use in identifying an
additional study area or areas include: (a) high levels of toxic emissions, based on information from
the Environmental Loadings Profile or emissions databases; (b) high prevalence of one or more
health indicators; or (c) Agency/Stakeholder consensus recommendations.
A subset of the most significant point sources affecting the study area will be selected for
detailed study. Emissions from these point sources will be modeled to identify locations with
maximum risk from multiple contaminants of concern. Cancer risks will be modeled for both child
and life-time receptors at these maximum risk locations. (Life-time receptors would be modeled in
addition to child receptors because cancer risks are greater when longer-term exposures (i.e., 30
years) are assumed.).
Both direct (inhalation) and significant indirect pathways of exposure will be included in the
risk assessment. Examples of indirect pathways which may be evaluated, if data indicate they are
-------
significant pathways to children, include contact with soil, waiter, and sediments to which
contaminants have been released through air deposition, and ingestion of contaminated produQe'br
fish which may have accumulated contaminants released from the point sources. _ ,-
Task2b: Exposure and risk from area, mobile, and background sources that also affect the
study locales will be evaluated, but in less detail. These risks will be combined with 'the
contributions from modeled point-sources impacting locations within the -study areas. Similarly/
screening-level estimates of both point- and area-source risks will be developed for Census tracts
throughout the larger area of concern (i.e., Cook and Lake Counties). These analyses are likely to
rely on modeling methods developed for the air'toxics portion of the EPA National Cumulative
Exposure Project, but to use more recent and more detailed area-specific data.
Task 2c: Estimates produced by the ambient air modeling efforts described above will be
validated by comparison to ambient monitoring data and results of detailed studies, where available.
An uncertainty analysis will also be conducted to evaluate the robustness of the findings.
33 Description of Other Risk Pathways (Task 3)
All parties involved in the scoping and planning process have agreed that focusing the '
cumulative risk assessment on EPA-regulated and EPA-permitted sources is most appropriate. As
a result, the most detailed portion of the cumulative risk evaluation will be the community-based
assessment of multiple EPA-regulated (and permitted) air sources, plus other outdoor air sources
(described in Section 32). Since emissions from these sources may contribute only .a portion of the
potential risks to a community, development of risk estimates for other sources and pathways will
be addressed in this task.
»
This evaluation will include both exposures from sources that are regulated by EPA and some
that are outside the direct control of the Agency. Exposure pathways from regulated or permitted
sources could include drinking water ingestion and soil ingestion at or near contaminated sites.
Examples of exposures that result from lifestyle and behavioral circumstances of children include:
ingestion of lead in paint and soil; ingestion of pesticides hi the diet; mercury and PCB ingestion
from fish consumption (especially subsistence fishing); and inhalation of environmental tobacco
smoke, radon, and other indoor air pollutants. Whenever possible, local (community-specific)
exposure data will be used in the assessment. In other cases, regional or even national estimates will
be used. While a comprehensive, community-based assessment of all exposures is beyond the scope
of this study, the attempt will be made to include pathways affecting the particular vulnerabilities
of children. Due to data and resource limitations, portions of the assessment of additional sources
and personal exposures will be more descriptive than quantitative.
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Appendix D. Slides from Presentations
1. Cumulative Risk Assessment Practicum Phase I Planning and Scoping
2. Problem Formulation: Lessons from Ecological Risk Assessments
3. Conceptual Model Development
D-l
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Cumulative Risk Assessment
Practicum
Phase I: Planning and Scoping
November 12-13,1998
Chicago, Illinois
(Introductory Slides)
Sponsored by the
Science Policy Council
Presenter
Edward S. Bender, Ph.D.
SPC Staff
-------
Cumulative Risk Assessment Pracjicum
Phase I: Planning i
Cumulative Risk Work
Don Barnes, OA
Ed Bender, ORD
Carole Bravennan, Reg V
Pat Cirone, Reg X
Penny Fenner-Crisp, OPPTS
Michael Firestone, OPPTS
Lany Reed, OS WER
Joe Reinert, OP
James Rowe, ORD
JeanetteWiltse.OW
Bill Wood, NCEA
Ed Ohanian, OW
Cumulative Risk Guidance
Phase I Planning and Scoping
i Address aspects of CR within domain of
EPA regulations
i Establish a framework to plan for
integrated risk assessments
i Coordinate with Risk Characterization
Policy and Guidance
i Complement/promote use ofgutdefa
111
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Gumulative Risk Objective
the Practicum
• Learn to apply the guidance on planning
and scoping for cumulative risk assessment
• Develop a Plan and Conceptual models for
Case Studies.
• Discuss and practice approaches.
1 Identify CR needs and concerns for the
assessors and managers.
J
e
Risk Assessment
A
Risk Assessment/ Management Decision
New Mnngcmenl Needs
PUiming
and
Scoping
(Auoxr-
Muugcr
Economic, Poll-Science,
and Social Analysis
*-* .--•*"'**
Definition of Cumulative Risk
• "Risks from one or more stressors
considered in aggregate"
• Each Assessment is case-specific
• Who is affected or stressed?
• What are the stressors?
• What are the sources?
• What are the pathways?
• What is the time frame for the risk?
• What are the assessment endpoints?
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Planning and Scoping Quid,
Plan for an Integrated
Risk Assessment
Relies on existing
guidance and policy
Encompass current
practice, guidance, and
policies.
Guiddbe».Ec«iik,&qx»»t,
Ncorown., Repro.. Cwcer..
Pnynm Guidweeml Poficy
(RAGS. IcjiiUtioa. mUet)
Case Sudia illume
«pplicalionofP&S Guidance
EPA Policy-Risk Ctanaerizatioii
Peer Review. Models, etc.
Planning and Scoping
o Identify the Purpose, Scope, a
participants
o Develop a matrix of possibilities
• Define the actual risk matrix
o Determine assessment endpoints
© Conceptual Model
Problem Formulatio:
Risk Assessor Risk M
1. Backgrauad Koovledgc
•.idle of the riit
b. critical endpoinb
' concems
4. Political concerns
S. Timing/Resomccs
6. Acceptable Levels of
.. |i'tnt~~n
-------
Purpose of Dialog
Risk Manager should explain why a risk
assessment is needed and what questions
should be answered.
Surface policy and stakeholder concerns to
determine information needs and
contributors for planning the assessment
Discuss resources and participant roles.
Define the Scope of the risk
assessment
Identify the exposure scenarios, information
needs, and assessment issues to be
evaluated.
Set criteria for defining the technical scope.
Note judgements for risk characterization.
Define the Cumulative Risk
Dimensions and Elements
Develop a set of possible elements for each
dimension (see Outline) with participants.
Rank these elements in terms of data
available, relevance to the RM goal, etc..
Revisit these rankings as new data become
available.
-------
Cumulative Risk Dimensions and
Elements Provide
- Definition of cumulative risk for the
particular assessment
• A record of what was considered, included
and explicitly excluded from the analysis.
• The rationale for the these decisions.
Cumulative Risk Dimensions
Pathways
Problem Formulation
Iterative process for RA to develop
hypotheses about why adverse effects might
occur or have occurred.
Determine the assessment endpoints-
characteristics valued by society, and
related to the management objective(s).
Leads to a conceptual model.
-------
Conceptual Models
Show relationships between assessment
endpoints and stressors.
Reflects both scientific hypothesis and a
rationale for accumulating risks from
stressors affecting common receptors.
-------
Problem Formulation:
Lessons from
Ecological Risk Assessments
Mark A. Harwell and Jack Gentile
Harwell Gentile
tt Associate*, L.C.
-------
Framework for Ecological Risk Assessment
(EPA 1992, 1997)
Problem Formulation
Acquire Data,
Iterate Process
and Monitor
Results
Exposure
Risk Characterization
Harwell Gentile
& Auociatei, L.C.
-------
Problem Formulation
HarweU Gentile
Sc Associates, L.C.
-------
Relationship Between Societal Goals and Scientific Endpoints
and Measures in Ecological Assessments
(Gentile and Harwell 1996)
Societal
Relevance
Scientific Relevance
Harwell Gentile
& Associates, L.C.
-------
Learning and Feedback
Public
Officials
Implementation
Options and
Formulation Design
Natural and
Social Scientists
Decision
Deliberation
FIGURE 1-2. A schematic representation of the risk decision process.
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CATEGORIES OF ECOLOGICAL ENDPOINTS
HUMAN HEALTH CONCERNS
• vectors for exposure to humans of diseases or toxics
SPECIES-LEVEL ENDPOINTS
societal importance
• economic, aesthetic, recreational, nuisance, or endangered
species
ecological importance
interactions between species
habitat role
ecological role
trophic relationships
functional relationships
critical species
COMMUNITY-LEVEL ENDPOINTS
• food-web structure
• species diversity of ecosystems
• biotic diversity of ecosystems
ECOSYSTEM-LEVEL ENDPOINTS
• ecologically important processes
• economically important processes
• water quality
• habitat quality
LANDSCAPE-LEVEL ENDPOINTS
• mosaic of ecosystem types
• corridors for migration
• spatial and temporal patterns of habitat
• feedbacks to regional- and global-scale physical systems
-------
Ecological Endpoints for Freshwater Marsh
Ecosystems of South Florida
species-level endpoints
• Spartina spp. productivity
• Muhly productivity
• exotic species
community/ecosystem-level endpoints
hydroperiod/water levels
plant community structure
upland succession
biodiversity
periphyton productivity
water quality
• nutrient/oligotrophic status
feeding habitat for wading birds
landscape-level endpoints
mosaic— spatial (physical distribution across landscape)
mosaic— temporal (physical distribution across time)
connectivity of habitats (e.g., with sawgrass)
habitat fragmentation
substrate dynamics
stress response:
• storm frequency
• frost frequency
• fire frequency/intensity
-------
Cumulative Risk Elements
What are
The Questions ?
What are the relevant sources of stress?
What are the stressors of concern?
What are the relevant paths and routes of exposure?
Who and what are at risk?
What are the health assessment end points?
What are the ecological assessment endpoints?
Harwell Gentile
& Associates, L.C.
-------
Tampa Bay Bathymetry
0 5
Manatee Kilometers
-------
Tampa Bay Critical Habitats
Seagrass
• Mangroves
H Salt Marsh
— Sand Beac
-------
-4 -4 tl'A. MM ^w^HJ <.n«lfi
MANGROVES &
RSH GRASSES
PHYTOPUNKTON
(MICRO-ALGAE)
Sea Ituul
Suulhein MuuMiIci
RedlUh
Snuuk
Tdrnuii
MACJO ALGAE
Killlliili
Suul
Suo CattW.
-------
. ,••- .-»-. -. 1t A MM *
111
WIND
CURRENTS VERTICAL MOTION
I I
•••• •••
SLICK
DISPERSION
DISSOLUTION SEDIMENTATION
BIODEGRADATION ENTRAPMENT COALESCENCE EVAPORATION
Physical Processes in fate and Transport Models
-------
l.O-i
0.8—
CO
o
0.
0.2-
0.0
I Callinectes (Blue crab)
Cyprlnodon varlegatus (<2-hr-old embryos)
' Cyprlnodon variegatus (Minnow)
Cyprlnodon varlegatus (>4-hr-old embryos)
Ampelisca (Amphipod)
Penaeus (Pink shrimp)
Argopecten (Bay scallop)
Cynoscion (16-hr post hatch larvae)
Cynoscion (Seatrout yolk sac larvae)
Mysidopsls (Mysid shrimp)
0
50
100
I
150 200
Concentration (ppb BTEX)
250
Cumulative Distribution of Fuel OH #6, Water Soluble Fraction
Acute Toxlclty Data
-------
Shipping Navigation Channels to
Port Manatee and Sensitive
Environments in Tampa Bay
-------
• Oiled Sand Beaches
(Seagrass
| Mangroves
I Salt Marsh
| Impacted Seagrass
! Impacted Mangroves
Impacted Salt Marsh
Impacted Shallow Water/Nursery Habitats (< 1/2 m)
Adverse Condition Fuel OH #6 Spill
J
-------
Summary
Define goals and objectives
Establish spatial/temporal boundaries
Identify sources, stressors, and pathways
Define endpoints and measures
Construct conceptual models
Formulate stressor-response hypotheses
Rank stressor-effects relationships
Harwell Gentile
& Associates, L.C.
-------
CONCEPTUAL MODEL
DEVELOPMENT
JOHN H. GENTILE & MARK A. HARWELL
Harwell Gentile
& Associates, L.C.
-------
Conceptual Models:
Principles and Examples
Principles and rules
Format & structure
Watershed/habitat examples
RI/FS case study example
Harwell Gentile
""^ ft Associate*, L.C.
.w~
-------
Conceptual Model Definition
A spatially explicit graphical or text
description of the candidate causal
linkages among sources, stressors,
receptors and endpoints describing
the spectrum of potential risks.
^, Harwell Gentile
W*. 81 Associates, L.C.
-------
Framework for Ecological Risk Assessment
(EPA 1992, 1997)
Problem Formulation
Exposure
Risk Characterization
Acquire Data,
Iterate Process
and Monitor
Results
Cpmmunicatinggpesujte;
Harwell Gentile
& Associates, L.C.
-------
Problem Formulation
jk Harwell Gentile
.^SSB?Si. Sc Associates. L..C.
-------
Driver-Stressor-Effects Linkages
Harwell Gentile
& Associates, L.C.
-------
Conceptual Model Benefits
Provides explicit expression of the assumptions
and understanding of the system
Reduces the dimensionality of the problem
Tool for learning, communicating, and consensus
building
Describes explicitly the linkages among sources,
stress, and the ecological components at risk
Template for generating testable risk hypotheses
Harwell Gentile
. 8c Associates, L.C.
A
-------
Cumulative Risk Questions
What are the relevant sources of stress?
What are the stressors of concern?
What are the relevant paths and routes of exposure?
Who and what are at risk?
What are the health assessment endpoints?
What are the ecological assessment endpoints?
Harwell Gentile
&As«ociates,L.C.
-------
Conceptual Model Development
1. Define the goals and assessment context
2. Delineate scales and boundaries
3. Inventory land uses/activities
4. Describe the potential stresses and sources
5. Identify contaminant release mechanisms
Harwell Gentile
Sc A»»oct««es, L..C.
-------
Conceptual Model Development
6. Describe exposure pathways
7. Identify stressor - receptor co-occurrences
8. Identify health/ecological endpoints
9. Determine specific health/ecological measures
10. Develop a suite of risk hypotheses
11. Rank relative importance of potential risks
Harwell Gentile
*- & Associates, L.C.
-------
General Conceptual Model Format
Societal Drivers
(Landscape Activities)
I
System Stress
i
Stress Regime/Exposure Pathways
l
Disturbance/Stressor Co-occurrences
with Receptors
1
Primary/Secondary Effects
(Proposed Causal Linkages)
I
Health/Ecological Endpoints
4
Measurements
Harwell Gentile
8c Associates, L.C.
-------
Waquoit Bay Conceptual Model
EPA Watershed Case Study
Harwell Gentile
5. & Associates, L.C.
-------
Water and
Sediment Nutrients
Decree
Struam Gravel
Substrate
Estuarlne
Benthlc
Invertebrate
Community
Eelgrass
HabHat
CommunltvJ « c
/Invertebrate v/PlpIng Plover/ /ShelMlsW /
/ Indices. IBI/A least Tern / Fish
/Eelgrass Cover /
Abundance /;
of Resdent 3
-------
Agriculture Atmosphere Residential Dev. Industry
Marine Activities
Shoreline
Protection
and
Modification
-------
Plant accretion (since mid 1800's)
Precipitation
I
Fertilizers
Septic systems
Denitrified! ion
NH4+ adsorption
1.1
Nitrogen entering
coastal bay
x I Figure E-5. Inputs and fate of nitrogen (mol N x 10* yr') entering the watershed and traveling toward Buttermilk Bay near Waquoit Buy. Additional
sources not shown are precipitation directly onto surface waters and onto impervious surfaces that are washed into surface waters. (Reprinted from
"Couplings of Watersheds and Coastal Waters: Sources and Consequences of Nutrient Enrichment in Waquoit Bay, Massachusetts," by Valiela et ul.,
| | published in Estuaritt, December 1992, Vol. IS, No. 4, pp. 443-457, with permission from Estuaries. •Estuarhte Research Federation.)
-------
South Florida/Everglades Case Study
.^_ Harwell Gentile
A""1*, * AuocUwi. UC.
-------
South Florida Regional Environments
• Urban
D Open Water
• Cypress Swamp
Q Grassland and Agriculture
• Upland Hardwood Forest
I Coastal Saltmarsh
H Freshwater Marsh
• Mangrove Swamp
• Pinelands
• Shrub Swamp
H Exotic Plants
H Mixed Hardwood Swamp
£3 Dry Prairie
-------
Defining Spatial Boundaries:
Conceptual Model Landscape Units
Harwell Gentile
-------
• Sawgrass-Slough-Tree Island
• Fresh water-Cypress Swamp
• Marl Forming Wet Prairie
• Mangrove Estuary
V Coral Reef Tract
Coastal/Estuarine System
Rockiand Pine
• Lake Okeechobee
Pine Flatwoods
• Wet Prairie
Dry Prairie
yne Bay
-------
Biscayne Bay Conceptual Model
Harwell Gentile
& Associates, L.C.
-------
Biscayne Bay Conceptual Model
LAND & WATER
USE
HARVESTING
VESTING &\ / PHYSICAL
POACHING / V DAMAGE
SUSPENDED
SEDIMENTS
NTAMINANTSJ (ALTERED SALINITYI ( NUTRIENTS
BNCREASED
ALGAL
INCREASED
ALGAL
SEAGRASS
SCARS A
SPONGE
REMOVAL
MANATEE
INJURY
ALTERED
SEAGRASS
COMMUNITY
DISTRIBUTION,
GROWTH, AND
PRODUCTIVITY
ALTERED
HARD-BOTTOM
COMMUNITY
DISTRIBUTION,
GROWTH, AND
ODUCTIVITY
REDUCED
WATER
QUALITY
CHANGES
IN FAUNAL
COMMUNITY
SEAGRASS
COMMUNITIES
HARD-BOTTOM
COMMUNTTIES
MOBILE
MACRO-
ERTEBRAT
RARE&
ENDANGERED
SPECIES
LANDSCAPE
STRUCTURE
-------
Decision Support Methods
Best Professional Judgement (BPJ)
Delphi Method (Linstoneand Turoff, 1975)
Analytical Hierarchy Process (Saaty, 1990)
Fuzzy Set Theory (Zadeh, 1965, Harris et al. 1994)
Vital Issues Process (Engi and Glicken, 1995)
EPA/SAB Integrated Risk Project
Harwell Gentile
& Associates, L.C.
-------
Summary
Define goals and objectives
Establish spatial/temporal boundaries
Identify sources, stressors, and pathways
Define receptors, endpoints and measures
Construct conceptual models
Formulate stressor-response hypotheses
Rank stressor-effects relationships
Harwell Gentile
& Associates, L.C.
-------
RI/FS Conceptual Site Models
Chemical Stressor Model
Physical Stressor Model
Human Health Effects Model
Harwell Gentile
& Associates, L.C.
-------
RI/FS Conceptual Model Format
Inputs
i
Release Mechanisms (Primary /Secondary)
i
Affected Media/Secondary Sources
i
Exposure Routes
Receptors and Systems @ Risk
Primary/Secondary Health/Ecological Effects
I
Health/ Ecological Endpoints
i
Measures
Harwell Gentile
& Associates, L.C.
-------
RI/FS Site Boundaries, Sources,
and Stressors
Geography and Topography
Definine Spatially Explicit Sub-basins
Source and Stressor Characterization
Harwell Gentile
& Associates, L.C.
-------
SEGMENT 3,
Gorge Gulch >
SEGMENT 1
Ownership not mapf
Drimarily USFS land.
33
O'Neill Gulch
SEGMENT 2
SEGMENT 4
LEGEND
• Floodplain Tailings
• MF&G Water Quality Stations
• Producers
D Non Producers
• Cities
'SEGMENT 5
— •» —Segments
Land Status
I • • • I BUM
II II I Forest Service
Private
-------
-------
RI/FS Ecological Conceptual Site Models
Chemical Process Model
Physical Process Model
Harwell Gentile
& Associates, L.C.
-------
Inputs
Primary
Source wes
Primary Release Secondary T
Mechanisms | Release Mechanlsmp
Affected
Media and
Secondary Sources
Exposure
Routes
Receptors I Geographic
I Linkages
Riverine
Fish
Benlhlc
Invertebrates
Birds
Perfphytron
Contact, Ingestlon
Chemical
Process
Surface
Water and
Suspended
Solids
Surface Water
Erosion
Contact, uptake
Riparian
Plants
Soil
microbes
Soil
Invertebrates
Wildlife
Contact, uptake
Contact, Ingestlon
Inhalation
Contact, uptake
Contact, Ingestlon
Porcess
Wastes
Invertebrates
Wildlife
Preliminary Process Model
-------
Primary
Stressora
Fish Community
Structure/
Function
Altered Stream
Hydrology
Altered Stream
Morphology
Riverine
Rsh
Benthte
Invertebrates
Birds
Periphylron
Decreased pool habitat
Decreased run habitat
Decreased riffle habitat
Decreased cover
Destabilized banks
Barriers to migration
Riverine Invertebrate
Community Structure
Function
Spawning Habitat
Mine/Mill
Structures
Overwintering Hablte
Riparian
Plants
Soil
microbes
Other Process
Wastes
Riverine Migratory
Routes
Diversity of*§tructure
and Composition
Vegetation
Management
Altered Terrestrial
Habitat
mosaic
Loss ol connectivity
Loss of wildlife habitat
Loss ol soil structure/
function
Changed species
composition
Riparian and
Upland Migratory
Corridors
Son and Sediment
Quality and Function
Waterborne Log
Transport (past)
Upland
Plants
Soil
microbes
Invertebrates
Wildlife
Removal of
Soil and
Sediment
Roads and
Railroads
Landscape Mosaic
Forest Community
Structure/
Function
Stream
Channelization
Decreased Soil
Productivity
Housing and
Urban
Development
Selected Species
Increased Export
Sediments
Nutrients
Increased
Nutrients to
Stream
See Issues
Statement
Physical Stressors CSM
-------
RI/FS Health Effects Conceptual Model
Harwell Gentile
"" -". & Associate^ L.C.
-------
Inputs
Primary
Source "types
Primary Release I Secondary T
Mechanisms | Release Mechanlsmp
Affected
Media and
Secondary Sources
Exposure
Routes
Receptors Geographic
| Linkages
p
eclpltatlon
Preliminary Process Model
-------
Affected
Media and
Secondary Sources
Surface
Water
Pathways
Inhalation
Ingestion
(Water/Food)
Contact
(Dermal)
Receptors
—n Adults
Mine
Workers
Children
Infants
Endpoints
Carcinogenic
Neurotoxicity
Reproduction
Developmental
Cardio-vascular
Immunologic
Renal
Hepatic
Others
Measures
Human Health Effects
-------
Summary
Define goals and objectives
Establish spatial/temporal boundaries
Identify sources, stressors, and pathways
Define endpoints and measures
Construct conceptual models
Formulate stressor-response hypotheses
Rank stressor-effects relationships
Harwell Gentile
^2*!^. & Associates, L.C.
-------
Appendix E. Hypothetical Model Exercise
E-l
-------
HYPOTHETICAL CASE EXAMPLE FOR CUMULATIVE RISK
The Scenario
The area of concern is a regional environment consisting of the lower reaches of a major river
system, its associated floodplain, wetland, and estuarine ecological systems, a highly engineered
water management system, and a nearby urban population of 1 million people. The river system
drains a large area with extensive agricultural production; agricultural runoff adds significantly to
the river's already high load of suspended solids and turbidity. The river has very high levels of
nutrients, but because of the high turbidity (which lowers primary productivity) eutrophication does
not occur until the water reaches the estuary. The river also receives high levels of pesticides and
organic chemicals from non-point agricultural sources, point source discharges from a fertilizer
plant, and an extensive petrochemical industry with a variety of discharges. Alongside the river is
a levee built for flood control, and beyond that artificial levee is a floodplain with a natural ridge
some distance beyond. In between the two levees are natural wetlands, which are being rapidly
converted to open water systems because of the interference with the natural sedimentation
processes historically associated with floods. Further, some wetlands have been converted to
agricultural use and others have been converted to aquaculture (oysters and catfish ponds). The
remaining wetlands and croplands provide important habitat for migratory birds because the area is
located on a major flyway. Near the mouth of the river is an urban area, which contributes
significant discharges from storm water, municipal waste treatment facilities, and surface runoff.
The river opens into a delta at the estuary. Offshore is a growing hypoxic area, resulting from the
eutrophication of the estuarine waters because of excessive nutrient inputs, high secondary
productivity, and consequent depletion of dissolved oxygen.
The human populations of the area include workers in the agricultural and chemical industries, who
have high exposures to pesticides and toxic chemicals; a general urban population with a high
incidence of bladder cancer (4 times the national rate); and a sensitive population of asthmatics,
elderly, etc. exposed to high levels of particulates. Other ecological and/or human health issues
include high lead levels in sediments; bioconcentration of chemicals in fish and in fish-eating birds.
-------
NATURA
AGRICULTURE
AGRICULTURE
FLOODPLAIN
AQUACULTURE
INDUSTRIAL
PETROCHEMICAL
INDUSTRY
01-7/98
-------
Cumulative Risk Questions
What are the relevant sources of
What are the stressors of concern?
What are the relevant paths and routes of exposure?
Who and what are at risk?
What are the health assessment endpoints?
What are the ecological assessment endpoints?
A. Harwell Gentile
S^i. & Associates, L.C.
-------
Cumulative Risk Elements
What are
TheQwstons?
What are the relevant sources of stress?
What are the stressors of concern?
What are the relevant paths and routes of exposure?
Who and what are at risk?
What are the heatth assessment endpoints?
What are the ecological assessment endpohts?
What an
Sources?
Single Source
• point sources: industrial discharges, waste sites
• non-point sources: automobtes, agriculture
• natural sources: floods,hurricanes, fires
Multi-sources
• combinations of those above
Cumulative Risk Elements
What are
Stem?
Chemical
• toxic metals and orgarics
• nutrients
Physical
• liabtet alteration, floods, fires
• climate: precipitation, temperature, etc.
Steal
gens, dsease
•/invasive species
Societal
• economic
• psychological
-------
Cumulative Risk Elements
What are
Air
Surface water
Groindwater
Sols/sediments
Sold waste
Food
Non-food products
Cumulative Risk Bemefits
What an
Ingestion - food and water
Dermal - absorption and active uptake
Inhalation - includes gaseous exchange
Non-dietary Ingestion - hand-to-mouth behavior
Cumulative Risk Elements
What are
Direct contact or ingestjon without accumulation
Bioaccumulation
Biomagnifl cation
Vector transfer - parasites, pathogens, eta
-------
Cumulative Risk Elements
What are
Human
• Individuals
• General Population distribution or estimation of central
tendency and high end exposure
• Population subgroups: highly exposed subgroup (e.g.,
age* gender) and highly
sensitive subgroups (e.g., age
gender, pre-existing conditions)
What an
R«*fferCtf«oriMQRWc?
Ecological
Individuals
Populations
Communities
Ecosystems/Habiats
Landscapes/Regions
Watersheds
Regional scale ecosystems
Cumulative Risk Elements
What are
Carcinogenic
Neifotoxicdogcal
Reproductive Dysfunction
Developmental
Cardie-vascular
Immunologc
Renal
Hepatic
Others
-------
Cumulative Risk Elements
What ire
EoofaQtoilBndlpoMfc?
Species: growth, survival, reproduction, habiat role
Population: long-term growth, sustainability. resliency, etc
Community: biotic and species dversly, richness,
trophic structure, etc.
Ecosystem: structure, function, services, water quality,
habitat quality etc.
Landscape: habitat mosaic, connectivity, spatial-temporal
habitat patterns
-------
Appendix F. Case Study Results from the Break Out Sessions
(Brainstorming, lists of dimensions, ranking and priorities and preliminary linkages and
conceptual models)
I.CCRI
Presenter: Carole Braverman, Region V
Facilitator: Mark Harwell, University of Miami
F-l
-------
Chicago Cumulative Risk Initiative Case Study-November 12, 13, 1998
(Transcription from Hand-Written Notes on Charts, not in any particular order)
At Risk Populations-Human Health
General Population
Children (pre-school)
Elderly
Pregnant females
Asthmatics
Immuno-Suppressed
Exposure population
Industrial workers
Proximity to point sources
Economic&Cultural > subpopulation
Children
Smokers
2nd Hand smoke pop.
Sickle Cell Anemics/Genetic predisposition Confined populations
Economics/Cultural: subpopulations
Stressors (air)
Particulates
Bio-Aerosols Lead
Ozone
PAHs
Toxic Organics
Benzene
Metals
NOx and SOx
Odor
Mercury, PCBs, Dioxin
Cadmium
Chromium
Noise/vibration
Other Toxics
Flammables/Explosives
Endocrine Disrupters
Pesticides
Pathway Breakout
Dioxins
Eco-Receptors
(Fish)
Biomagnification
Human Receptor
Deposition
(aquatic)
Absorb particles
Inhale Deposition on Soil
Dermal contact
Inges
ion
F-2
-------
CCRI
Goals and Objectives
1. Understand environmental conditions of Cook and Lake County (Air quality
current focus) better
2. Use understanding as basis for:
-(future) permitting decisions
- communication with stakeholders
3. Determining societal goals in region
4. Determining if multiple contaminant sources are in COMPLIANCE (to result in
healthy environment)
SPATIAL/TEMPORAL Boundaries
1. Political boundary: Cook Co. (IL) and Lake Co. (IN)
Endpoints: Human Health
Cancer—
Childhood leukemia
Lung cancer
Breast Cancer
Other Cancers
Non-cancer—
Asthma Developmental
COPD Cardio-Vascular
Birth Defects Acute Effects
Neurological Reproductive Disorders
Immunological Behavioral Effects
F-3
-------
Human Health and Ecological Risk Assessment
SOURCES (Air)
- Steel Mills
- Oil Refineries
- Incinerators
-WWTP
- Mfg. Plants
- Small Point Sources
- Recycling (Metals)
- Indoor Air
- Background sources
- Asbestos
- Land mgt. burning
- Landfills
- Chemical Plants
- Power Generation Plants
- Airports
- Mobile
- Pesticides (lawn/golf pest control)
- Lake Michigan
Endpoint - Eco
Lake (Aquatic)
UrbanHabitat AG
Tall grass
Prairie
Migratory birds
Species carp
Community
Ecosystem
Landscape
Dunes Forest Preserves
Neotropical Earner blue Amphibians
Birds butterfly Deer
Tree health
Maintain biodiversity
Decomposition Air filtering
Processes
F-4
-------
SOURCES
Steel mills
Mfg. plants
Small point sources
Indoor air
Mobile
Incinerators
Agriculture
STRESSQRS
Toxics:
organics
Pesticides
PCB/Dioxin
PAH
Benzene
Endocrine Disrupters
Inorganics:
Metals: Pb, Hg, Cr, Cd
Particulates
Noise
Odor
Ozone/NOx/SOx
(Pathways presented below)
Sources Stressors
Incinerators End. Disrupters
ENDPQINTS
Human:
Cancer: leukemia, lung, breast,
Other
Respiratory :COPD, asthma
Dev./Reprod./Birth Defects
Neuro./Behav.
Cardio-Vascular
Immune
Eco:
Neotropical Birds
Tree Health
Biodiversity
Deer
Endpoints
Agriculture
Incinerators.
Mfg. plants
Indoor air
Mobile
Agriculture
.Odor
F-5
-------
Sources
Steel mills
Incinerators
Mfg. plants
Agriculture
Stressors
Participates
Pesticides
Endpoints
(Human)
Cancer
Dev./Reprod./BD
Neuro/Behav.
Immune
Incincerators
Indoor air
Mobile
PAH
Mfg. plants ....................... PCB/Dioxin_
Cancer
Neuro/Behav
Immune
Steel mills
Mfg. plants
Indoor air
-Metals
ECO
Mfg. plants
Small pt sources
Mobile
.Ozone/NOx/SOx.
Tree Health
Biodiversity
Noise
Neotropical birds
Tree health
Biodiversity
Deer
F-6
-------
Pentachlorophenol-Assigned Participants
Presenter: Nader Elkassabany and Wanda Jacobs, Office Pesticide Programs
Facilitator: Jack Gentile, University of Miami
B. Pentachlorophenol
Presentation of case on PCP
Milestones
used only for wood preservation, 1987
Working with PMRA-NAFTA
Doing work sharing with work plan dividing up tasks
Eco, human health etc. So won't duplicate work
Regulated under other laws
STAKEHOLDERS are industry, trade assoc., public, environmental groups
? Ho w do you mediate differences—No set formula (Karen Me); senior management and public
ultimate determiners; strong impetus to agree based on NAFTA
Chemistry
Usage~25 products registered for use
Hazard ID
-B2 carcinogen
-microcontaminants important; used TEFs and TEQs used to set criteria
Environmental Hazards
-limited eco effects; relying on ORD and contractor support—will be qualitative assessments
Human Exposure Scenarios
Human Exposure Pathways
Environ. Exp Pathway
Issues/Uncertainties
? Any indication of unintentional dietary exposure (beddding shavings used in hog farms);
swine showed PCP residues (Karen Me)--Wanda-some people using railroad ties for gardening;
Should be considered in conceptual model development? Canada requiring accountability for
bedding source-not sure how big problem; no requirement for putting wood into RCRA site in
Canada, and the US
Process for breakout group—id sources, stressors, pathways, endpoints; start inclusively could
go outside PCP; broaden conceptual model to include microcontaminants (perhaps 2nd model)
F-7
-------
Do PCP and if time do microcontaminants
What about alternative—creosote, CCA-looking at relative risk assess.; may more relevant to
look across agents to evaluate relative toxicity; be careful not to eliminate less toxic material;
What are expectations? Jack
Tutorial, how to apply
PCP with contaminants (Karen's preference)
CR Risk Elements—the Questions
Potential Sources-PCP and microcontaminants
(Karen—looking at overall contribution to dioxin contamination in environment)
-wood treatment plants
-manufacturing
-disposal: landfill sites/recycled-re-dimensioned/incineration
-in-use/service: utility poles(soil), marine dock pilings (aquatic), residential (decks/outdoor
only),
residential (indoor)
Stressors
-PCP
-furans/dioxins (lump because can evaluate with TEFs
-hexachlorobenzenes (HCB)
(stressors must be in contact with receptors)
Pathways of exposure~eco and human health
? Is psychological legitimate stressor (stress)-yes; relates to contaminants; could put on human
side; however, not part of US thinking at this time but is in Canada-will put in as endpoint.
-runoff onto surface water
- ground water
- soil,
- air (volatilization)
-dietary
-treated wood
Routes of exposure
-ingestion
F-8
-------
-contact
-inhalation
Review of approaches from yesterday/RI/FS model—1)Aggregate in how stressors move
through environment together (process approach), 2) Waquoit Bay approach-sources at top,
stressors at bottom, then stressor-driven analysis
*
Biscayne Bay model—little simpler approach; major sources at top, stressors sources,
pathways, major habitats impacted (freshwater stream communities, etc.); develop broad
pathways and put in detail; suggest to build simply but capture major issues; look in more detail
later on
Need to flesh major habitats of concern and then pick the endpoints
Major Receptor Habitats/classes impacted
-terrestrial community/soils (unsure if available in plants—may be thru air deposition)
-streams/waterbody
-estuarine
-marine
-human: 1) occupational: workers in plant, utility pole workers, handlers,
2) residential (adults, children)
(Conceptual models are accompanied by extensive text—Jack)
Receptor Habitats: Endpoints:
PCP Dioxin/Furans HCB
Terrestrial: Floral diversity NA NA
-acute effect
Soils: Earthworms Birds (earthworms)
Microbes Mammals(voles,
Invertebrate community moles)
Raptors (subreceptor)
Habitat quality
Freshwater: Fish community Fish/fishing
Invertebrates Mammals (mink, otters)
Raptors(birds, waterfowl)
Water quality
Marine: Benthic invert. Cornm. Same
F-9
-------
Fish/bottom feeders Shellfish
plants
Occupational: Teratogenicity
Cancer, renal, stress
Genotoxicity, subchronic
Residential: developmental
neurotoxicity
Next step rough out conceptual model using Biscayne Baymodel (flip charts)
Manufacturing Water treatment. Transportation Disposal Poles Pilings Residential
PCP Dioxins/Furans HCB
terrestrial Soils freshwater marine occupational residential
(Flora diversity)
passerine birdsearthworm pop
voles
hawks
(see hand written graphic)
Might be useful to look at receptor hits for manufacturing; do ranking of sources to receptors-
Jack
Manufacturing
terrestrial (runoff)
marine (effluent/spill, air deposition?)
occupational (inhalation, ingestion, dermal)
residential (stack emissions)
fresh water (effluent/spill, runoff)
soils (runoff, leaching)
Wood treatment
F-10
-------
contaminated soils (runoff)
fresh water (runoff/effluent)
marine (runofFeffluent)--geographic (east coast primarily)
occupational (dermal, ingestion, inhalation?)
Transportation (tanker truck on road)
soils
fresh water
occupational
Disposal (landfills)
soils
fresh water
Poles
soils
occupational
residential
Pilings
marine
Miscellaneous (wood/homes)~replaces residential
residential
Ranking exercise for human pathways and environmental pathways/routes of exposure was
performed at the first practicum and was used in this exercise (see tables at the end of
discussion). Ranked for each source not across sources.
Environmental Pathways/routes of exposure
F-ll
-------
(Secondary routes were identified to wildlife but didn't identify links to human life (in analysis)
2 hooks)
Process for breakout group-identify sources, stressors, pathways, endpoints; start inclusively
could go outside PCP; broaden conceptual model to include microcontaminants (perhaps 2nd
model). The group agreed to focus first on PCP and if time do microcontaminants.
What about alternatives—creosote, CCA—looking at relative risk assess.; may more relevant to
look across agents to evaluate relative toxicity; be careful not to eliminate less toxic material;
The expectations were that this case would serve as a tutorial on how to apply the guidance to
the risk assessment of this case.
Cumulative Risk Elements-the Questions
Potential Sources-PCP and microcontaminants.
(Karen—looking at overall contribution to dioxin contamination in environment)
-wood treatment plants
-manufacturing
-disposal: landfill sites/recycled-redimensioned/incineration
-in-use/service: utility poles(soil), marine dock pilings (aquatic), residential (decks/outdoor
only),
residential (indoor)
Stressors
-PCP
-furans/dioxins (lump because can evaluate with TEFs
-hexachlorobenzenes (HCB)
(stressors must be in contact with receptors)
Pathways of exposure—eco and human health
? Is psychological legitimate stressor (stress)--yes; relates to contaminants; could put on human
side; however, not part of US thinking at this time but is in Canada-will put in as endpt.
-runoff onto surface water
- ground water
- soil,
- air (volatilization)
-dietary
F-12
-------
-treated wood
Routes of exposure
-ingestion
-contact
-inhalation
Review of approaches from yesterday/RI/FS model-1)Aggregate in how stressors move
through environment together (process approach), 2) Waquoit Bay approach—sources at top,
stressors at bottom, then stressor-driven analysis
Biscayne Bay model-little simpler approach; major sources at top, stressors sources,
pathways, major habitats impacted (freshwater stream communities, etc.); develop broad
pathways and put in detail; suggest to build simply but capture major issues; look in more detail
later on
Need to flesh major habitats of concern and then pick the Endpoints
Major Receptor Habitats/classes impacted
-terrestrial community/soils (unsure if available in plants—may be thru air deposition)
-streams/waterbody
-estuarine
-marine
-human: 1) occupational: workers in plant, utility pole workers, handlers,
2) residential (adults, children)
(Conceptual models are accompanied by extensive text—Jack)
Receptor Habitats: Endpoints:
PCP Dioxin/Furans HCB
Terrestrial: Floral diversity NA NA
-acute effect
Soils: Earthworms Birds (earthworms)
Microbes Mammals(voles,
Invertebrate community moles)
Raptors (subreceptor)
Habitat quality
Freshwater: Fish community Fish/fishing
Invertebrates Mammals (mink, otters)
F-13
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Raptors(birds, waterfowl)
Water quality
Marine: Benthic invert. Comm. Same
Fish/bottom feeders Shellfish
plants
Occupational: Teratogenicity
Cancer, renal, stress
Genotoxicity, subchronic
Residential: developmental
neurotoxicity
Next step rough out conceptual model using Biscayne Bay model (flip charts)
Manufacturing H20 trait. Transportation Disposal Poles Pilings Residential
PCP Dioxins/Furans HCB
terrestrial Soils freshwater marine occupational residential
(Flora diversity)
passerine birdsearthworm pop
voles
hawks
Might be useful to look at receptor hits for manufacturing; do ranking of sources to receptors-
Jack
Manufacturing
terrestrial (runoff)
marine (effluent/spill, air deposition?)
occupational (inhalation, ingestion, dermal)
residential (stack emissions)
fresh water (effluent/spill, runoff)
F-14
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soils (runoff, leaching)
Wood treatment
contaminated soils (runoff)
fresh water (runoff/effluent)
marine (runoff/effluent)~geographic (east coast primarily)
occupational (dermal, ingestion, inhalation?)
Transportation (tanker truck on road)
soils
fresh water
occupational
Disposal (landfills)
soils
fresh water
Poles
soils
occupational
residential
Pilings
marine
Miscellaneous (wood/homes)~replaces residential
residential
Ranking exercise (human pathways)
Management Goal: Review HDWPs in sequential order; then do comparative risk analysis.
> Review wood preservatives as a class
> Assess each class individually
> Revisit each class as a group/cumulative risk/comparative risk
Planning Process: Use pentachlorophenol as a model/template.
To Build a Matrix:
F-15
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Point/Non-point?
Health/Ecological?
Pathways: human/eco?
HUMAN
Occupational
Accidental (L)*
Occupational (H)*
Occupational (L)
Occupational (RCRA)
Children (L) (?)
(L)
(L)
Residential Occupational
(L)
ECOLOGICAL
Aquatic
Spill
Aquatic (L)
Soil (L)
Aquatic (H)
Soil (L)
Aquatic
Soil/Water (H)
(L)
SOURCES
Manufacturing
Transport [of chemicals and logs]
Wood Preservative Facility
Utility Poles [localized]
Disposal of Treated Poles [consumer misuse]
Residential Uses (e.g., decks)
Fences
Pilings, Piers, Docks
Remedial Ground line Treatment
Farm buildings/Industrial buildings
*L=Low, HHHigh
Action: Enhance dialog between OP/AD and ORD: e.e., exposure pathways and toxicology.
Need to assume "partners" are providing appropriate information.
Air Emissions: Gene Grumpier from Kelly Rienert at workshop.
Pathways
Human Pathways/Routes of Exposure
SOURCE
Manufacturing
Transportation
Wood Preservative Facility
Utility Poles
Disposal of Treated Poles
DERMAL
High
High
Low
Low (RCRA Issue)
INHALATION
Low
Medium
Low
Low
INGESTION
Low
Low
Low
Low
F-16
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Residential Uses/ subpopulation-children
Peaces
Pilings, Piers, Docks
Remedial Ground line treatment
a. Occupational
b. Residential
Farm Buildings/Industrial Buildings
Medium - children
Low
Low (N/A)
Low
High
Low
Low
Low
Low
Low
Low
Low
Medium
Low
Low
Low
High
Low
Human Health Endpoints
> Liver
> Carcinogenicity
> Immunotoxicity
> Endocrine Disruption
> Kidney
> Neurotoxicity
> Developmental Toxicity (Teratogenicity)
Environmental Pathways/Routes of Exposure
SOURCE
Manufacturing
Transportation - Parked
Wood Preservative Facility
Utility Poles
Disposal of Treated Poles
Residential Uses/ subpopulation-children
Fences
Pilings, Piers, Docks
Remedial Ground line treatment
DERMAL
Low?
Low
Low
Low (RCRA Issue)
Low
Low
Low
INHALATION
Low?
Low
Medium?
Low
Low
Medium?
Medium
INGESTION
High
Low
Medium?
Low
Low
Medium?
High
F-17
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a. Occupational
b. Residential
Farm Buildings/Industrial Buildings
Low
Low
Low
Medium
Medium
Low
Low
Low
Low
Environmental Endpoints
A. Aquatic Organisms
>Fish
> Invertebrates
> Aquatic Plants
B. Terrestrial Organisms
>Bird
> Mammals
> Invertebrates- need receptor for
analysis/
scoping
Mortality
/
/
S
/
/
Reproduction
/
/
/
F-18
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III. Concentrated Animal Feeding Operations
Presenter: Gerald Carney, Region VI, Dallas, TX
Facilitator: Larry Reed, Superfund, Ed Bender, OSP, Washington, DC
Preliminary comments and questions on scope and background
Needed to clarify that the Cumulative Risk Index Analysis was a screening process, which used
GIS data, being applied to a Concentrated Animal Feeding Operation,
Initially there was some confusion over the sources within a CAFO
The terminology of stressor needed a bit of clarification.
There were human health, quality of life and human welfare issues associated with CAFOs
watershed impact seems like good approach
what is cum risk aspect- either an addition of stressors to a watershed or siting of multiple
facilities.
odor and disease were main human effects; can capture as economic loss as well as risk.
List of factors for each dimension of the CAFO project
Assessment End points
-Sustainable natural grassland prairie ....
-biodiversity (richness, evenness)
Plant Communities
Wildlife communities
Sport and recreational fish and their habitats
Maintain a designated stream use for the water shed or stream segment
Habitats which may contain endangered species
Stressors
Turbidity
Nitrate-nitrogen (ammonia)
Nitrite-nitrogen
Phosphorus (phosphate)
Sulfur (hydrogen sulfide, sulfides)
Aerosol chemicals
Noise
Dust, particulates
Odor (also considered as an effect)
Pathogens
Attractive nuisance to waterfowl
Pesticides
Drugs and antibiotics
Waste feed
F-19
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Manure
Road Deterioration/construction and maintenance
Water quantity (groundwater withdrawal, water table draw down)
Increased traffic
Higher taxes
Sources
One or more CAFOs within a watershed
-lagoon
-barns
-land application system
-trucks
Other sources within the watershed which contribute similar stressors
-Expansion of other farms
-Urban areas looking for growth and higher land use
-Federal facilities
-Industry-particularly oil and petroleum exploration in Texas setting.
-Septic tanks and drain fields
-POTWs
Measurement end points
1. Fish, invertebrates, aquatic community
-water quality measurements
-water borne pathogens
-algal populations, abundance and diversity, photosynthetic indices....
-endocrine disrupters
2. Terrestrial ecosystem (prairie)
-number of birds vs. control areas (literature for screening
-endangered species, other special species (presence, absence, abundance)
3. Human health
-incidence of disease, self-reported
-medical survey data (screening)
-complaints to local and state doctors and health service, police, firm and rescue
-could address EJ health (Indian reservations for example)
Effects
F-20
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Siltation
Loss of water clarity
Anoxia
Odors causing anxiety and stress
land-use changes
algal blooms-eutrophication of lentic waters
aesthetics
met-hemoglobanemia from nitrites in water supply
headaches, dizziness, nausea
fish flesh tainting
Inability to urban/suburbanize (residential development fbre'cftfsed)
Fish effects of silt
Traffic accidents
Spills of materials
Water quality damage
Road deterioration
Habitat fragmentation due to new and wider roads
Wetlands dry up
Disease to humans and domestic and wild animals.
The group focused on nutrients and toxic effects on the watershed, habitat degradation
and loss for the uplands, and nuisance (e.g., odor, flies, and increased traffic) and land-use
commitments as effects of concern to humans. The group was not aware of any studies on
human disease or other human health effects related to these CAFOs. Several people noted that
this is the kind of issue that sparks a lot of public interest and concern, but that most federal
agencies and state agencies are powerless to address. Region VI is using the NPDES permit
process to set some conditions on these facilities, however, this discussion shows that it is far
more that can and should be considered than the traditional limitations placed on sewage
treatment facilities.
The group also discussed how this might be used to communicate the nature of the
problem and the issues of greatest concern to the public. The process of planning and scoping
was very helpful to open up the thinking of the participants and share experiences they had
about related problems and approaches. The group found that several stressors caused multiple
effects, e.g., ammonia as a nutrient for algae and being toxic to fish.
The group put together a preliminary diagram of the dimensions of the risk assessment,
but the linkages were not completed.
F-21
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The role of stakeholders in the screening process was unclear. In some instances, this
type of analysis was prompted by public requests for assistance or review.
F-22
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Appendix G. Comments and Suggestions from Participants
Comments on Chicago Colloquium
Most useful:
1. Outline of conceptual model and planning and scoping. Practice in the breakout sessions.
2. Seeing this from the ecological standpoint and a human health perspective.
3. Breakout session case studies to flesh out the guidance and conceptual models.
4. The examples presented on the first day and the working experience in the break-out session
were the most useful.
5. The format was excellent, concepts, hypothetical case and the real case study. Good balance
between into. Lectures, walk-through, and break out exercises.
6. Glad the discussion was not limited to existing data.
7. The advance materials were very helpful background. They articulated the main themes of
human health and ecological risk assessments and the problems of merging them into a
cumulative risk assessment.
Aspects to change:
1. Seems like first day could be done more quickly, get to the discussion of the hypothetical
earlier, let the detailed diagram be shown later, at least to some extent.
2. I would not change any aspect, but I probably would add to them when holding future
practicums.
3. The connection to cumulative risk was unclear and the presentations were almost too basic.
4. The hypothetical needed more basic facts and foundation regarding the proposed action site.
5. Add an analytical component to address conceptual models and rankings.
6. Offer more ideas on how to merge ecological and human health risks into one cumulative
risk assessment. Explain the differences.
G-l
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7. Some examples of human health risk assessment would be useful.
8. Make more tune for the case study evaluation.
9. Separate ecological risk and health risk to avoid confusion about the terau'nology. Once
people have gone through the process it would be easier to join the disciplines.
Recommendations to strengthen the discussions and practicum:
1. Move to hypothetical earlier in presentation.
2. Add information on tools for diagram drawing and GIS
3. Add expert on human health and examples of human health cumulative risk assessment to
the introduction.
4. From a regulatory point of view, the practicum needs to strengthen the areas where no data
are available to determine potential exposure. Next what happens when the model is complete-
how is it converted to a numerical model.
5. Need to look more at how it applies to regulatory program and sites.
6. Need to go beyond scoping/planning/conceptual models.
7. Unclear how ranking individual stressors fits into true cumulative perspective.
8. Take environmental justice into account. Continue to emphasize stakeholder (interested and
affected parties) involvement at the problem formulation stage.
9. Make more time to explain and work with the conceptual models (the breakout sessions
helped). Perhaps have software that could draw a conceptual model.
10. More discussion of stressor-endpoint ranking exercise. Demonstrate software for producing
conceptual models.
11. Add extra day for to flesh out and apply the model in the case studies.
12. Identify issues up-front: 1) program level use of the exercises and 2) spatial scope for the
analysis.
13. Make the handout maps and charts clearer.
G-2
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Case Studies
1. The case study was useful in serving as an example of developing a conceptual model as well
it is of direct interest since re-evaluation of PCP is currently in progress.
2. Not sure that cumulative risk assessment is the correct term for what we did.
3. Look at cumulative risk and compare what drives risk (i.e., scientific methods) with
community pressures and politics and economics.
4. CCRI is a good example of a case that has intense public interest
5. Discriminate between incremental and aggregate cumulative risk.
G-3
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Appendix H. Draft Conceptual Model
H-l
-------
PCP Human Health Conceptual Model
Sources
Pathways
Dermal Exposur
.:..-• . -;.. ... f.fc" •;-.. ;..,-;- JL •-
(—esidential-")
(--Occupatiorfcl
Exposed
Populations
Adults
Non-
pregnant
Adults
-Pregnant
Fetus
Adults
Non-
pregnant
Adults
-Pregnant
Fetus
Toxicity
Endpoints
Occupat/Residential
Nonpregnant
-Acute Toxicity (high)
-Subchronic/chronic
-reprod. & genotox
-endocrine disruption
-stress(high?)
1
Occupat/Residentia
Pregnant
Same endpoints as
non-pregnant, plus
-developmental tox.
and neurotoxicity
Children
-neonates
-child
^ -juvenile
Children
-Reproductive
-Developmental Tox
incld. Neurotox.
-Endocrine Disrupt.
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