Human Activity-Environment Interaction at the U.S.-Mexico Border
Craig Forster1 and Tjeerd Schaafsma2
Introduction
The Border+20 (B+20) Project is designed to develop a modeling framework for
supporting interdisciplinary, binational decision-making along the 3,200 km U.S.-Mexico
Border Region (Figure 1). The principal goal for this effort is derived from the vision
statement generated at the first Border Institute convened by the Southwest Center for
Environmental Research [1999]: to aid borderland decision-makers in finding ways to
maintain a satisfactory quality of life for all residents and a healthy sustainable natural
environment. To this end, the Border+20 Project is tasked with projecting future conditions
along the U.S.-Mexico border for a series of alternative 20 year futures (hence the 20 in the
project name Border+20).
As recommended by Kinsley et al. [2002] we use a systems thinking approach to map out
key elements of the borderland human-environment system and to build system dynamics
models that quantitatively represent complex linkages, flows, and feedbacks between and
within system elements. The interdisciplinary B+20 Project Team comprises researchers
from five U.S. universities involved in the Southwest Center for Environmental Research and
Policy (SCERP) consortium (Arizona State University, New Mexico State University, San
Diego State University, University of Texas at El Paso, University of Utah) and five Mexican
academic institutions (Universidad Autónoma de Baja California, Universidad Autónoma de
Ciudad Juárez, Instituto Tecnológico de Ciudad Juárez, Instituto Tecnológico y de Estudios
Superiores de Monterrey, El Colegio de la Frontera Norte). Disciplinary expertise
represented by the team members includes, but is not limited to: border studies, hydrology,
air quality, energy supply/demand, water resources supply/demand, urban planning,
psychology, economics, demography, sociology, ecology, earth science, human health and
communication. Our goal is to provide a modeling framework for decision-making that will
increase the likelihood for improved transborder cooperation and help lead to a sustainable
future for those living along the U.S.-Mexico border.
United States of America
Mexico
Figure 1. U.S.-Mexico border (heavy black line) and neighboring Border States (gray) in the
United States and Mexico.
1. Geology & Geophysics Department, University of Utah
2. Physics Department, San Diego State University
A Brief Synopsis of the U.S.-Mexico Border Region
The 3,200 km long U.S.-Mexico Border Region (Figure 1) spans the North American
continent with 15 principal, sister-city communities distributed along the border. County
populations in the U.S. border region range up to 2.8 million people in west coast city of San
Diego, U.S.A. with a total of 6.4 million people in the U.S. borderlands. The corresponding
populations of Mexican ‘municipios’ (Mexican equivalent of U.S. counties) range up to 1.3
million people in the San Diego sister-city of Tijuana, Mexico with a total of 5.7 million
people in the Mexican borderlands. Rapid population growth leads to projected 2020
populations of 9.0 million and 10.5 million U.S. and Mexico border residents, respectively
[Peach and Williams, 2000]. Thus, the current total borderland population of about 12.1
million people is likely to increase by more than 60% to 19.5 million over the next 18 years.
Most population growth will occur in the existing, transborder sister cities where intense
interaction between human activity and the environment is concentrated. At the same time
long, desolate stretches of desert between the principal sister-cities are essentially
unpopulated, leading to significant difficulties in restricting the illegal flow of people and
drugs from Mexico to the United States. The tremendous rate of population growth was
initially caused by Mexican citizens migrating to work in the economically attractive border
region. Relatively high fertility rates and relatively low death rates in this young population
of migrants has led to a rapid natural population increase that would continue even if
Mexican migration to the border were to end [Peach and Williams, 2000].
Geographic conditions vary substantially along the border with high, north-south oriented
mountain ranges in the western border region separating border communities located at
elevations ranging from sea level (at both coastal and inland communities) to 1,234 meters
above sea level. In the east, community elevations are generally less than 300 m above sea
level. The border region has a semi-arid to arid desert climate with precipitation ranging
from less than 10 cm per year at some inland communities to 70 cm per year on the east
coast. With the exception of the west coast communities of San Diego, U.S.A. and Tijuana,
Mexico, annual average maximum temperatures are about 29 oC and average minimum
temperatures about 16 oC. Cooler temperatures on the west coast yield an annual average
maximum of 21 oC and an average minimum of 14 oC for San Diego, U.S.A. and Tijuana,
Mexico. The specter of future natural and anthropogenic climate variability suggests that we
should be concerned by the possibility that declining precipitation rates and increasing
temperatures will cause additional stress on borderland water, energy, natural resources and
ecosystems.
Economic growth stimulated by border attributes (e.g., attractive differentials in labor
wage rate, enforcing of environmental laws, etc.) has been substantial since the 1940s [Peach
and Williams, 2000]. In 1994, implementing the North American Free Trade Agreement
(NAFTA) between Canada, the United States and Mexico further stimulated economic
growth. Unfortunately, the conditions that stimulate economic growth at the border have
yielded low per capita incomes and high unemployment rates when compared to those
elsewhere in the U.S. Although per capita incomes in the Mexico border communities are
much greater than those elsewhere in Mexico, Mexican border minimum wage rates are
approximately 10% of that of their U.S. sister city counterparts [Peach and Williams, 2000].
High rates of economic and population growth, coupled with low incomes, have meant that
Forster & Schaafsma
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many environmental problems have developed in the U.S.-Mexico border region because
insufficient public financial resources exist to meet rapidly expanding infrastructure needs.
The current U.S. economic recession, combined with increasing attractiveness of low labor
wage rates in countries such as China, raises concerns that the borderland economic
expansion of past decades may slow while the borderland population continues to grow.
Economic stagnation in the border region would exacerbate current environmental problems
and deteriorating human quality of life because access to the funding needed for
infrastructure development will be further eroded.
Water availability and quality, air quality, human health, and ecosystem health are key
elements of the borderland human-environment system suffering as a consequence of high
population growth rates and rapidly expanding urban areas. In the arid climate of the border
region there is increasing competition for the scarce water resources needed for human
consumption, agricultural production, industrial activity and ecosystem health. Average per
capita water use in the U.S. borderland (615 liters per capita per day) is about 41 % greater
than that of the Mexico borderland (435 liters per capita per day) [Westerhoff, 2000].
Because water use is correlated to standard of living, efforts to improve the quality of life in
the border region could lead to increased per capita rates of water use unless counteracting
measures of efficient water conservation and recycling are introduced. Binational planning
for efficient water use and system-wide wastewater treatment is required if sister-city
communities are to develop a sustainable water supply future while also reducing the
prevalence of water-borne disease.
Weakly enforced environmental regulations in Mexico border communities are allowing
excessive air pollution that, in turn, causes the air quality in several sister-cities to exceed
U.S. national standards; despite relatively low emissions in the U.S. sister cities. Imaginative
approaches are needed to develop cost-effective reductions in the binational air emissions
that impact quality of life and human health on both sides of the border. Natural ecosystems
in the borderland desert environment have been severely punished by human activity. Yet, in
many cases well-managed desert ecosystems can provide cost-effective solutions to water
supply challenges encountered in human communities [Committee on Sustainable Water
Supplies for the Middle East, 1999]. For example, water supply development has eliminated
many natural riparian areas that at one time provided natural water treatment in addition to
habitat for indigenous flora and fauna. However, artificial wetlands recently constructed in
the U.S. Imperial Valley region are helping to remove the suspended solids introduced to
surface water by the irrigation runoff associated with agricultural activity. We expect that
our systems thinking and modeling approach will assist in evaluating the relative merits of
various options proposed to mitigate the degradation of natural systems in the borderland and
improve the quality of life for people living in the U.S.-Mexico border region.
A Systems View of the U.S.-Mexico Border
The principal elements of a binational, human-environment system model are shown in
Figure 2. Population and economic growth drive change in a borderland community.
Ultimately, changes in both the economy and population are influenced by the way that
border inhabitants respond to concerns regarding human health and other aspects of quality
of life. At the same time, quality of life is strongly influenced by the changes in land use,
Forster & Schaafsma
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transportation, energy, water supply, air quality and ecosystem services that are driven, in
turn, by changes in population and economic activity. Each model element shown in Figure
2 represents the processes operating on both sides of the border. The detailed system model
structure, however, explicitly distinguishes between processes operating on each side of the
border and the processes that cause the transfer of ‘stuff’ across the border. An important
contribution of the systems approach is that we explicitly account for the linkages, feedbacks
and interactions across the border that are often not fully considered by decision-makers
working independently on each side of the border.
‘Stuff’ flowing within the border region includes water (good and poor quality), air
(polluted and otherwise), disease, money, products (food, agricultural, commercial,
manufacturing, entertainment, etc.), waste products, social capital, services, electricity, fuels,
vehicles, light, sound, ideas, community spirit, flora and fauna. In many cases, human
activity at the border restricts flow of ‘stuff’ across the border with the most active
restrictions occurring at the ports of entry found in sister-city communities. Notable
exceptions include the transborder movement of groundwater in binational aquifers,
migration of air pollution in transborder airsheds and the movement of indigenous flora and
fauna within and through regional ecosystems. The movement of other ‘stuff’, however, is
restricted by the physical, economic, legal and spiritual presence of the border.
Population
Land Use
Transportation
Energy
Quality of Life
Water Supply
Air Quality
Ecosystem Services
Economy
Figure 2. Overview of the elements of a borderland system model of human activity and the
natural environment. Although additional arrows are not shown for the sake of clarity, all
elements within the shaded circle interact with one another to varying degrees.
A thought experiment proposed by the B+20 project team asks: “How might the
borderland human-environmental system change if all restrictions on transborder flows were
removed?”. Once this scenario is thoroughly mapped then it would be valuable to compare it
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to one where all flows that can be controlled are severely restricted. Several different
outcomes could be envisioned for each scenario. It is hoped that such an exercise would help
to define a mix of binational policies that would lead to a sustainable future for borderland
inhabitants. For example, removing all restrictions on human migration across the border is
expected to cause massive movement of Mexican citizens to the U.S. Although one should
expect an initial period of enhanced migration, people will only migrate across the border as
long as conditions in the new location are clearly preferable to those in their home
community. As people move from place to place their behavior modifies the demographic
and economic conditions at each location while consuming natural resources. At the same
time, ties to one’s home community are difficult to break – perhaps even more difficult when
it is easy to travel home frequently in the absence of border restrictions. Thus, it seems
reasonable to expect that an equilibrium population distribution should result. In the absence
of performing a quantitative, multifaceted calculation, however, it is difficult to guess when
such an equilibrium condition might be reached and how the total population of Mexican
nationals
might
be
distributed
between
the
two
countries.
Furthermore, it is unclear whether net economic impacts on the two nations would be
positive or negative when equilibrium is attained. At this stage in the B+20 project,
however, we are focused on more localized geographic targets with smaller-scale questions
aimed at better informing decision-making in specific sister-city communities.
Figure 3 shows the three sister-city border communities to be considered in our current
model development activity; El Paso (U.S.A.)/Ciudad Juárez (Mexico), Calexico
(U.S.A.)/Mexicali (Mexico) and San Diego (U.S.A.)/Tijuana (Mexico). Although all three
locations have a similar set of underlying conditions (climate, borderland economic drivers,
population drivers, etc.) social, economic, natural resources and geographic differences
dictate that separate models be constructed for each sister-city community. To date our
model development effort has focused on El Paso/Ciudad Juárez. We recently expanded our
effort to develop a separate model to explore complex water-supported ecosystems in the
Salton Sea, California near Calexico/Mexicali (Figure 3). As this work expands, we will
move progressively westward to develop a Baja California model that contains the sister-city
communities of Calexico/Mexicali and San Diego/Tijuana in order to explore how to satisfy
increasing San Diego/Tijuana demands for water and energy from the regions shown in
Figure 3.
The El Paso/Ciudad Juárez System Model
Although it is beyond the scope of this brief statement to outline the details of the El
Paso/Ciudad Juárez system model, a brief outline of several key model sectors should help
illustrate how we are proceeding. Two key questions have been defined to help frame the
development of the model sectors:
Question 1 - Given the various state and national water management agencies involved in
supplying water from common sources to urban communities and agriculturalists, what
changes in agency policies and approaches might be effected to increase the likelihood
for achieving water sustainability and satisfactory quality of life for borderland residents?
Question 2 - Given transborder disparities in minimum wages and household income, what
policies might be effected to increase the likelihood for providing a healthy economy and
satisfactory quality of life for borderland residents?
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A principal emphasis in our effort to assure a satisfactory quality of life for border
inhabitants involves assessing how human health along the border is affected by changes to
the human-environmental system captured in Figure 2 and vice versa.
Attempting to answer the above questions has led us to develop a system model with a
subset of the elements shown in Figure 2. These elements include the all-important
population, economy and quality of life sectors combined with land use, transportation, water
supply and air quality sectors (Figure 4). The foundation for each sector is briefly described
in the following paragraphs.
l
Ca
El Paso
Ciudad Juárez
i fo
i
rn
a
San Diego
Tijuana
Calexico
Mexicali
Arizona
New
Mexico
Texas
Baja California
Sonora
Chihuahua
Coahuila
Nuevo Leon
Tamaulipas
Figure 3. Current Border+20 geographic, sister-city targets (circles) and U.S. and Mexico
Border States (shaded). System dynamics models are being constructed for each sister-city
context.
Population & Economy Sectors:
Both national and local scale binational population and economy sectors are contained in
the system model because national-scale population growth, in part, fuels change in both
national economies that, in turn, influences borderland sister-city economies. A simplified
view of the population and economy interactions at the national level is shown in the causal
loop diagram of Figure 5. Underlying assumptions include the following:
1. Changes in the U.S. economy have a strong impact on Mexico’s economy and
unemployment rate, but not vice versa,
2. Estimates of national unemployment rate and economic productivity per worker are
key factors controlling the national Gross Domestic Product (GDP) of both the
U.S. and Mexico, and
3. Migration of Mexican nationals to the U.S. is largely driven by a differential in
GDP between the two countries.
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The (+) and (-) signs noted at the heads of each arrow shown in Figure 5 indicate whether an
increase in the source parameter causes an increase (+) or decrease (-) in the target parameter.
For example, because growth in the U.S. national GDP is typically greater than that of
Mexico’s GDP, increasing U.S. GDP leads to an enhanced binational economic differential
that helps to drive the migration of Mexican nationals to the U.S. At the same time, growth in
Mexico’s GDP helps to close the gap and reduce the binational economic differential.
Assigning values and relationships within the model that are appropriate to the region
produces plausible, national-scale economic and population projections that include a
sporadic cycle of economic recessions that mimics that of past recessionary cycles. For
example, the population of El Paso is projected to grow from 0.76 million in 2000 to 1.1
million people in 2020 while the population of Ciudad Juárez is projected to grow from 1.2
to 2.4 million people over the same time period [Peach and Williams, 2000].
Population
Land Use
Transportation
Quality of Life
Water Supply
Air Quality
Economy
Figure 4. Overview of the elements of a borderland system model of human activity and the
natural environment for the El Paso/Ciudad Juárez region distilled from that of Figure 2.
Although additional arrows are not shown for the sake of clarity, all elements within the
shaded circle interact with one another to varying degrees.
A simplified view of the population and economy interactions at the local level is shown
in the causal loop diagram of Figure 6. Underlying assumptions include the following:
1. National employment trends are reflected in the local economies,
2. Changes in employment for Ciudad Juárez reflect the combined impact of changes
in both the U.S. and Mexico national economies because the Ciudad Juárez
economy is strongly controlled by the ‘maquiladora’ industry that provides
product assembly factories in the Mexico borderland for U.S. industrial partners,
3. The El Paso economy is closely tied to that of Ciudad Juárez because many
maquiladora suppliers are based in El Paso and workers living in Ciudad Juárez
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frequently shop in El Paso. Thus, declining employment in Ciudad Juárez leads
to declining economic activity and employment in El Paso.
4. A strong local economy, reflected in high levels of employment in Ciudad Juárez,
drive migration to the sister-city from elsewhere in Mexico.
Changes computed in the local Population and Employment sectors provide the foundation
needed to compute consequent changes in Land Use, Transportation, Water Supply, Air
Quality, and Quality of Life sectors in both El Paso and Ciudad Juárez. It is critical to
incorporate transborder processes and relationships at the local level because this is where
the consequences of binational decision-making will be most severely felt by the sister-city
inhabitants.
Land Use:
The Land Use sector separately tracks the growth in urban land of El Paso and Ciudad
Juárez as a function of population growth and a user-defined target population density for
each increment of growth. Options are provided to enable the user to define what portion of
the urban expansion is at the expense of non-irrigated dry land and what portion eliminates
irrigated agricultural land. Where irrigated land is eliminated, options become available to
transfer to municipal and industrial use the irrigation water that would otherwise have been
used for agricultural production. Tracking the area of irrigated land, and the amount of water
required for specific crop types, provides the foundation needed to compute projected
changes in agricultural water use.
Mexico-to-U.S.
Migration
+
+
U.S. National
Population
+U.S. National
Labor Supply
_
U.S. National
Unemployment
Rate
+
_
U.S. National
GDP
U.S. National
Production
per Worker
+
+
Mexico National
Population
Binational
Economic
Differential
+
_
Mexico National
Labor Supply
+ _
Mexico National
Production
per Worker
Mexico National
GDP
+
_
Mexico National
_ Unemployment
Rate
Figure 5. Simplified causal loop diagram of the national level, binational, combined
Population and Economy sectors contained in the B+20 El Paso/Ciudad Juárez system
model.
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U.S. National
Unemployment
Rate
El Paso
Population
Mexico National
Unemployment
Rate
+
El Paso
Unemployment
Rate
+ El Paso
Ciudad Juarez
Unemployment
Rate
_
+
Employment
_
+
Ciudad Juarez
Employment
+
+ +
U.S. National
GDP
+
Mexico Internal
Migration to
Ciudad Juarez
Mexico National
GDP
Ciudad Juarez
Population
+
Figure 6. Simplified causal loop diagram of the local level, binational, combined population
and economy sectors contained in the B+20 El Paso/Ciudad Juárez system model. Note that
the national (Figure 5) and local level diagrams (this figure) are linked through the U.S.
National GDP and Mexico National GDP components that are common to both diagrams.
Transportation:
Transportation-related air pollution emissions make a significant contribution to the air
quality of the El Paso/Ciudad Juárez urban airshed where most people in the region live and
work. We account for the mobile vehicle emissions in the area by tracking the emissions that
might be released by the amount of gasoline and diesel fuel sold in the border community.
Given that the Ciudad Juárez vehicle fleet is older than that of El Paso we apply an extra
emissions output to the portion of fuel presumed to be used by the fleet licensed in Mexico.
In addition, however, we apply an extra emissions output for cars and trucks idling for long
periods (hours) at the border crossings while waiting to enter the United States [Ganster et al,
2000]. Recent, unanticipated increases in border security at U.S. ports of entry since
September 11, 2002 have created longer than usual vehicle wait times. Strategies proposed
for increasing the vehicle processing capacity at the border to reduce vehicle wait times
include adding additional security personal, expanding the ports of entry, implementing
technological improvements that speed up non-invasive truck inspections, and providing
special visa-passes for pre-screened people and vehicles. Tradeoffs in cost and effectiveness
of these alternatives have yet to be fully evaluated. The length of unpaved roads that form an
important source of particulate emissions grows with urban expansion – particularly in
Ciudad Juárez. Thus, growth in urban land area computed in the Land Use sector forms a
foundation for estimating particulate emissions from unpaved roads.
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Water Supply Sector:
The Water Supply sector is one of the most complicated elements of the El Paso/Ciudad
Juárez system model because we track water supply, water use, water reuse, water treatment,
water conservation and water quality in the sister-city urban community and the adjacent
agricultural areas. In this desert environment, water flows are carefully controlled and
monitored at many points in the surface hydrologic system. Controls managed at the
Elephant Butte Dam located upstream of El Paso/Ciudad Juárez ensure that surface water
transported through canals, pipes and the Rio Grande/Rio Bravo river is distributed according
to the various local agreements, state laws and international treaties. In times of drought the
various agreements stipulate how much water each entity is allowed to use. In some cases,
U.S. ‘western water law’ could cause some users to receive no water while others continue
receive a large portion of the amount of water they have used in the past.
The Water Supply sector accounts for the water made available from surface water and
subsurface groundwater aquifers. Because there are no binational, or interstate, agreements
regarding who ‘owns’ the groundwater, water managers from both sides of the U.S.-Mexico
border are pumping groundwater at a rate that is leading to a rapid decline in water volumes
stored in the aquifers. Water used for agricultural production is treated separately from water
used for municipal and industrial (M&I) purposes. In both cases, however, consumptive
water loses during use are estimated and applied to produce a reasonable accounting of water
flows through a hydrologic system dominated by the works of man. User defined options are
provided to mimic the effects of reinjecting treated wastewater to the aquifers, recycling
treated wastewater, conserving water, and supplying treated wastewater to agriculturalists.
Water quality is estimated throughout the hydrologic system by tracking the quantities of
total dissolved solids (TDS) at various points in the system: when released from the dam,
after both agricultural and M&I losses are accounted for, and following post-use wastewater
treatment processes. An option is provided in the system model to account for the way that
TDS values increase in the river during periods of drought. Once the TDS concentrations
and water flows of the hydrologic system are mimicked in the models, then we can proceed
with reasonable confidence to assess the consequences of a variety of water management
alternatives intended to provided greater access to higher quality water throughout the
binational community.
Options are provided in the model for users to explore an alternative currently being
discussed for both El Paso and Ciudad Juárez. Namely, increase annual use of surface water
by both communities. As this transition occurs, it will become necessary to negotiate with
upstream agricultural users how to deal with the elevated TDS values that they cause when
returning runoff from irrigated agricultural land to the hydrologic system [Turner, 2000].
Similarly, it will be necessary to negotiate with downstream agricultural users over the
quality of water that is released to the hydrologic system from municipal treatment plants.
Air Quality Sector:
Transportation-derived air pollution emissions described in a previous paragraph are
combined with industrial and residential emissions to compute emissions outputs for each
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city and a total contribution to the binational airshed. Industrial emissions are computed
from estimates of emission rate per employee while residential emissions are estimated from
emissions rate per dwelling unit. The number of dwelling units is computed using an
estimate of the average number of people living in a dwelling unit and the population of each
sister city.
Quality of Life:
Quality of life factors are currently represented in the outcomes computed for other
sectors. For example, air emissions provides insight regarding prospective changes in the
incidence of respiratory disease while the portion of wastewater that is treated and the portion
of dwellings connected to water and sewer provide insight regarding prospective changes in
the incidence of water-borne disease. In addition to tracking these health-specific indicators
of quality of life, we track changes in the per capita income that influences the quantity and
quality of water, food and housing that can be purchased by border residents.
Project Status
Our prototype model of the El Paso/Ciudad Juárez human-environmental system is
largely complete. Initial testing shows that we can mimic many attributes of the system.
However, additional data and model adjustment are required before the model is ready to be
viewed by the public. We expect to present our prototype to stakeholders and decisionmakers in the next few months and engage them in defining a refined set of questions to be
explored while also helping us to refine the model to best suit their needs. Previous meetings
with stakeholders and decision-makers in El Paso and Ciudad Juárez suggest that advocacy
groups, municipal planners and border health organizations should be most interested in
exploring alternative binational futures with a system dynamics model of their sister-city
community.
As we work towards completing the El Paso/Ciudad Juárez system model we are
expanding our research activities to include developing a system dynamics model that will
help to explore the high-profile policy issues associated with the non-urban, but urbanaffected, Salton Sea human-environmental system. This effort will link well with our plan to
study and model human-environmental systems in the Calexico/Mexicali urban/agricultural
community
An important goal of the B+20 Project is to provide a foundation for guiding SCERP
research. This outcome has been realized because SCERP research grants are awarded, in
part, by how well the proposed research will inform the integrative thinking embodied in the
B+20 models and the model development process.
Acknowledgements: The many people involved in the interdisciplinary B+20 project team are key
to developing an integrated systems model of human activity-environment in the U.S.-Mexico border
region. In addition to the authors, research team members include Ed Balsdon, Kim Collins, Phil
Emmi, Chris Erickson, Cesar Fuentes, Subhrajit Guhathakurta, Vince Gutschick, Ed Hamlyn, Oscar
Ibañez, Mike Kjelland, Herb Ortega, Sergio Peña, Margarito Quintero-Nuñez, Ed Sadalla, Al
Sweedler, and Jim Williams. We are grateful for the research, facilitator and administrative support
provided by Tracylee Clarke, Natasha Cleveland, Erik Lee, Barbara O’Donnell, Jane Riquelme and
Rebecca Royer. Our Advisory Board, Bill Grant and Tarla Peterson, has provided critical insight and
Forster & Schaafsma
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greatly assisted in developing and implementing the B+20 project. Funding is provided by the
Southwest Center for Environmental Research and Policy (SCERP) through grants from the U.S.
Environmental Protection Agency. This project would not be possible without the considerable
enthusiasm and ongoing assistance of our EPA partners Paul Rasmussen and Patrick Whelan; Rick
van Schoik (SCERP Managing Director); and the SCERP Management Committee.
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