# *GREEN TRANSIT SCHEDULER*: A METHODOLOGY FOR

JOINTLY OPTIMIZING COST, SERVICE, AND ENVIRON-MENTAL PERFORMANCE IN
DEMAND-RESPONSIVE TRANSIT SCHEDULING

Final Report

Metrans Project 01-6

November 2002

Revised: April 2004

## Mansour Rahimi

## Maged Dessouky

Merrill Weidner

University of Southern California

Department of Industrial and Systems Engineering

Los Angeles, CA 90089-0193

![](media/image1.png){width="2.9270833333333335in"
height="1.3020833333333333in"}

### DISCLAIMER

The contents of this report reflect the views of the authors, who are
responsible for the facts and the accuracy of the information presented
herein. This document is disseminated under the sponsorship of the
Department of Transportation, University Transportation Centers Program,
and California Department of Transportation in the interest of
information exchange. The U.S. Government and California Department of
Transportation assume no liability for the contents or use thereof. The
contents do not necessarily reflect the official views or policies of
the State of California or the Department of Transportation. This report
does not constitute a standard, specification, or regulation.

### ABSTRACT

Many types of transportation systems, for example, public transit and
commercial freight hauling and package delivery, may be categorized as
being fleet operations. The environmental impacts of fleet operations
such as these are affected by factors including the initial choice and
selection of vehicles (types) comprising the fleet, vehicle age and
maintenance, and the modal conditions under which the vehicles are
operated including. And, the environmental impacts are even more
significant when examined on a life-cycle basis. When examined on this
basis, it is clear that "cleaner" fuels, alone, do not provide an
environmental panacea or eliminate all of the environmental impacts of
transportation. Moreover, many of the life-cycle impacts can be directly
or indirectly attributed to vehicle operation. Controllable life-cycle
impacts may also be affected by vehicle routing and scheduling
decisions, in particular, in the case of a heterogeneous fleet. And,
these other controllable environmental impacts of transportation systems
and operation must also be considered if the overall impacts are truly
to be minimized.

There has been little prior work that has considered environmental
impacts in fleet vehicle routing and scheduling optimization, in
particular, where the impacts were assessed systematically utilizing
life-cycle impact assessment (LCIA) methodologies such as those
described by SETAC (1993, 1991) and in current ISO standards (ISO
14040). In this report, we present a methodology and algorithm for the
joint optimization of cost, service, and life-cycle environmental
consequences in vehicle routing and scheduling, which we develop for a
demand-responsive (paratransit or "dial-a-ride") transit system.
Importantly, as a prerequisite to accomplishing this, we develop a
decision-theoretic-based model for combining the results of multiple,
current LCIA methods, as suggested by Bare, et al. (2000). And, we use
the results of this model as the basis for specifying necessary
weighting constants in the vehicle routing and scheduling objective
function. We demonstrate through simulation that, as a result of our
methodology, it is possible to reduce environmental impacts
substantially (up to 25 percent or more) while increasing operating
costs only slightly (about two to four percent). These results are
predicated upon situational factors such as fleet composition, system
loading, and vehicle-specific costs and environmental parameters. We
felt the need to produce a large amount of empirical data in preparation
to prove our concept. We feel that the results presented in this report
are adequate to demonstrate the potential benefits of the methodology.

TABLE OF CONTENTS

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| **ABSTRACT                                                        | * |
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| #### LIST OF FIGURES AND TABLES .........................         | * |
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| **DISCLOSURE                                                      | * |
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| #### ACKNOWLEDGEMENT .....................................        | * |
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| **INTRODUCTION                                                    | * |
| .................................................                 | * |
| ...............................................................** | 1 |
|                                                                   | * |
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| TRANSPORTATION ENVIRONMENTAL IMPACTS                              | 2 |
| ......................................................\...        |   |
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| VEHICLE ROUTING AND SCHEDULING WITH ENVIRONMENTAL CONSIDERATIONS  | 3 |
| ........                                                          |   |
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| PROBLEM DESCRIPTION AND SOLUTION APPROACH                         | 4 |
| ..................................................                |   |
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|                                                                   |   |
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| **PARATRANSIT LIFE-CYCLE MODEL                                    | * |
| ......................                                            | * |
| ...........................................................\...** | 4 |
|                                                                   | * |
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| **LIFE-CYCLE IMPACT ASSESSMENT BASIS                              | * |
| .............                                                     | * |
| ...........................................................\...** | 6 |
|                                                                   | * |
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| SELECTION OF PROXY ATTRIBUTES FOR HUMAN HEALTH AND                | 7 |
|                                                                   |   |
| ECOLOGICAL DAMAGES                                                |   |
| ...........................                                       |   |
| .............................................................\... |   |
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| **DECISION-THEORETIC BASIS AND MODEL                              | * |
| ..........                                                        | * |
| ...............................................................** | 8 |
|                                                                   | * |
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| BASIC DECISION MODEL                                              | 9 |
| ..........................                                        |   |
| .............................................................\... |   |
+-------------------------------------------------------------------+---+
| AGGREGATION OF PROXY ATTRIBUTES                                   | 1 |
| ..                                                                | 0 |
| ................................................................. |   |
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| DECISION-MAKER PREFERENCE ASSUMPTIONS, EVALUATION OF SINGLE-      |   |
+-------------------------------------------------------------------+---+
| ATTRIBUTE UTILITY FUNCTIONS, AND OVERALL UTILITY EQUATION FORM    | 1 |
| ................                                                  | 1 |
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| EVALUATION OF END-POINT DAMAGE-BASEDUTILITY FUNCTIONS             | 1 |
| .............................                                     | 5 |
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| EVALUATION OF MID-POINT DAMAGE-BASED UTILITY FUNCTIONS            | 1 |
| .............................                                     | 6 |
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| EVALUATION OF RESOURCE DEPLETION AND OTHER IMPACTS UTILITY        | 1 |
| FUNCTIONS ...\...                                                 | 6 |
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| EVALUATION OF VALUE- (PREFERENCE-) BASED WEIGHTING CONSTANTS      | 1 |
| ..................                                                | 7 |
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| CALCULATION OF ITINERARY (ENVIRONMENTAL) UTILITY FUNCTION         |   |
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| VALUES AND DEFUZZIFICATION OF RESULTS                             | 1 |
| .........................................................\...     | 7 |
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| DECISION MODEL TRANSLATION FOR USE IN OPTIMIZATION---CALCULATION  |   |
+-------------------------------------------------------------------+---+
| OF "UNIT PARTIAL UTILITY VALUES"                                  | 1 |
| ......                                                            | 8 |
| ................................................................. |   |
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|                                                                   |   |
+-------------------------------------------------------------------+---+
| #### PARATRANSIT OPERATION, MODELED SYSTEM AND MULTI-OBJECTIVE    |   |
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| **SCHEDULING ALGORITHM, AND EXPERIMENTAL DESIGN                   | * |
| ................................................\...**            | * |
|                                                                   | 1 |
|                                                                   | 8 |
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| PARATRANSIT VEHICLE SCHEDULING                                    | 1 |
| .....                                                             | 9 |
| ................................................................. |   |
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| MODELED PARATRANSIT SYSTEM AND OPERATION                          | 2 |
| ................................................\...              | 0 |
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| SIMULATION MODEL AND MODEL VERIFICATION/VALIDATION                | 2 |
| ..................................                                | 1 |
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| BASIC REAL-TIME SCHEDULING HEURISTIC                              | 2 |
| ..............................................................    | 1 |
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| MODIFICATION TO INCLUDE ENVIRONMENTAL IMPACTS                     | 2 |
| ...........................................                       | 2 |
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| EXPERIMENTAL DESIGN                                               | 2 |
| ..........................                                        | 3 |
| .............................................................\... |   |
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| **EXPERIMENTAL RESULTS                                            | * |
| ..................................                                | * |
| ...............................................................** | 2 |
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| #### CONCLUSIONS AND RECOMMENDATONS ..........                    | * |
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| #### IMPLEMENTATION ............................................  | * |
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| #### APPENDIX                                                     |   |
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| A. VEHICLE LIFE-CYCLE IMPACT ASSESSMENT BASIS                     | 4 |
| ........................................                          | 2 |
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| B. VEHICLE (PARTIAL UNIT) UTILITY FACTOR BASIS                    | 6 |
| .......................................\...                       | 2 |
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| C. VALUES OF ASSUMED DECISION-MAKER SCALING CONSTANTS             | 8 |
| ......................                                            | 0 |
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| ##                                                                | * |
| ## REFERENCES ................................................... | * |
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### LIST OF FIGURES AND TABLES

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| [FIGURES]{.underline}                                          | [PA |
|                                                                | GE] |
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| 1\. Paratransit Operation Life-Cycle Model                     | 5   |
| ..................................................             |     |
+----------------------------------------------------------------+-----+
| 2\. Basic Decision Model                                       | 9   |
| ...........                                                    |     |
| ..........................................................\... |     |
+----------------------------------------------------------------+-----+
| 3.  Model for Evaluation of Constructed Attributes with Value  | 11  |
|                                                                |     |
| > and Factual Judgments Decoupled                              |     |
| > ......................................................\...   |     |
+----------------------------------------------------------------+-----+
| 4\. Linguist Variables for Damage Comparison                   | 12  |
| .............................................                  |     |
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| 5a. Combined Fundamental and Means-Ends Network for Health     | 28  |
| Damages .........\...                                          |     |
+----------------------------------------------------------------+-----+
| 5b. Combined Fundamental and Means-Ends Network for Ecological | 28  |
| Damages .......                                                |     |
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|                                                                |     |
+----------------------------------------------------------------+-----+
| [TABLES]{.underline}                                           |     |
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|                                                                |     |
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| 1\. Life-Cycle Inventory for Modeled Vehicle Types             | 29  |
| ....................................\...                       |     |
+----------------------------------------------------------------+-----+
| 2\. LCIA Equivalency and Hazard Ranking Factors                | 30  |
| ........................................                       |     |
+----------------------------------------------------------------+-----+
| 3\. LCIA Damage Function Indicators by Impact Category         | 31  |
| ...............................                                | -32 |
+----------------------------------------------------------------+-----+
| 4.  Normalized Values of ***b***~Xlijk~ Used in Evaluation of  | 33  |
|     Human                                                      |     |
|                                                                |     |
| > Health and Ecological Damage Potential                       |     |
| > .................................................            |     |
+----------------------------------------------------------------+-----+
| 5\. Unit Partial Utility Values Used in Simulation             | 34  |
| ..........................................                     |     |
+----------------------------------------------------------------+-----+
| 6\. Values of Selected Simulation and Experimental Parameters  | 35  |
| .........................                                      |     |
+----------------------------------------------------------------+-----+
| 7\. Comparison of Service Performance Results for Simulated    | 36  |
| Cases ...................                                      |     |
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| 8\. Scheduling Algorithm Results---Cost and Environmental      | 37  |
| Performance .............                                      |     |
+----------------------------------------------------------------+-----+
| 9\. Comparison of Results Affecting Environmental Performance  | 38  |
| .....................\...                                      |     |
+----------------------------------------------------------------+-----+
| 10a. Scheduling Algorithm Results---Life-Cycle Criteria and    | 39  |
| Other                                                          |     |
|                                                                |     |
| Pollutant Air Emissions                                        |     |
| ........                                                       |     |
| ..........................................................\... |     |
+----------------------------------------------------------------+-----+
| 10b. Scheduling Algorithm Results---Other Life-Cycle Impacts   | 40  |
| ...........................                                    |     |
+----------------------------------------------------------------+-----+
| 11. Comparison of Life-Cycle Emissions---Percentage Change in  | 41  |
|                                                                |     |
| > Average Daily Emissions Due to New Scheduling Algorithm      |     |
| > ........................                                     |     |
+----------------------------------------------------------------+-----+

[DISCLOSURE]{.underline}

**Funding Source:**

METRANS Transportation Center, USC/CSULB

**Names of principal investigators:**

Mansour Rahimi

Maged Dessouky

**Total Dollar Amount:**

\$50,000

**Title of Project:**

Green Transit Scheduler: A Methodology for Jointly Optimizing Cost,
Service, and Life-Cycle Environmental Performance in Demand-Responsive
Transit Scheduling (Project 01-6)

**Relationship to report:**

The report was written by the Principal Investigators and their PhD
student, Merrill Weidner

**Subcontract statement:**

Project was funded in entirety under this contract to California
Department of Transportation

### ACKNOWLEDGEMENT

This research was entirely supported by Metrans Center and its funding
agencies: the Department of Transportation and California Department of
Transportation. The research team also thanks Access Services, Inc., for
their on-going support and the information/data they provided to
complete the analysis. We also thank our graduate assistant, Hamid
Pourmohammadi, for his help in this research.

### INTRODUCTION

The environmental impacts of transportation are significant; and, these
impacts are even more significant when examined on a life-cycle basis.
When examined on this basis, it is also clear that anticipated "clean"
fuels and technological innovations of the future, alone, do not provide
the complete solution for minimizing transportation environmental
impacts or providing environ-mentally sustainable transportation
systems. For example, consider "zero emitting" electric vehicles, which
transfer emissions from the tailpipe to the electric utility, or the
much-heralded "fuel cell," which requires a hydrogen source that must be
produced and distributed by some means. This is to say, even with
cleaner fuels, other aspects of transportation system design and
operation must also be addressed if overall or life-cycle environmental
impacts of transportation systems are to be minimized.

From this analysis, it might be inferred that one key to minimizing the
life-cycle environmental impacts of transportation is simply to minimize
the transportation activity itself, since many of the direct and
indirect environmental impacts are a function of, or can be attributed
to, vehicle operation. While this is true conceptually, it is not
feasible to implement in many circumstances, for example, in public
transportation and commercial freight hauling systems that are operated
because of statutory requirements or to service an anticipated demand.
Typically, systems such as these utilize a fleet of vehicles---not
uncommonly, a fleet comprised of different types of vehicles, e.g.,
having different capacities or capabilities. Here, the controllable
environmental impacts of operation are affected by vehicle assignment
and/or scheduling decisions. However, in a (heterogeneous fleet) system
such as this, the relationship between vehicle activity, e.g., travel
distance to satisfy a particular demand, and environmental impacts is
situational and dependent upon vehicle parameters and the vehicle
assignment including itinerary. In other words, the vehicle assignment
and routing that minimizes distance or economic cost may not be the one
that minimizes environmental impacts. Moreover, the environmental
impacts are a function of variables in addition to travel distance
alone. However, by considering these impacts to be a function of
scheduling decisions, and including them in the scheduling optimization
function, these impacts can be optimized (minimized) jointly with other
decision variables.

The assignment or dispatching of vehicles in fleet operations entails
vehicle routing, vehicle scheduling or a combination of both, following
the taxonomy of Bodin and Golden (1981). And, problems such as these
have been extensively studied by Operations Researchers over the years.
However, there has been only very limited research to-date where
environmental considerations have been included in the vehicle routing
and scheduling objective function and optimization algorithm. In
particular, there has been virtually no research of this type that has
included environmental impacts assessed on a life-cycle basis.

In this paper, we present a methodology for optimizing vehicle routing
and scheduling based on the joint optimization of cost, service, and
life-cycle environmental impact parameters. We develop the methodology
for a demand-responsive (also known as "dial-a-ride" \[DAR\]) transit
system. In the U.S., the Americans with Disabilities Act requires
municipal transit operators to accommodate disabled patrons. And, for a
variety of reasons including safety and schedule maintenance, many
municipalities have elected to do so through the provision of
complementary transit (also known as paratransit), allowable under
federal law, rather than by modifying existing bus fleets. While
paratransit is only a small component of public transit overall, the
number of miles traveled in the U.S. has doubled over the past ten years
to nearly 600 million miles per year, according to the National Science
and Technology Council (NSTC, 1998). And, demand for such services is
expected to grow as the population ages demographically. More
importantly, "high operating costs and poor management strategies that
do not optimize the use of drivers and vehicles have made such services
costly and less than fully responsive to their riders' mobility needs"
(NSTC). These same underlying factors would be expected to affect the
environmental impacts of operation, as well, the joint optimization of
paratransit cost, service, and environ-mental performance.

[Transportation Environmental Impacts]{.underline}

At the present time, 107 areas of the U.S. are not in compliance with
one or more of the Ambient Air Quality Standards established by the
federal Clean Air Act, including those for carbon monoxide (CO),
nitrogen dioxide (NO2), sulfur dioxide (SO2), ozone (O3), lead (Pb), and
particulate matter (PM-10) (United States Environmental Protection
Agency \[USEPA\], 2002). And, a significant contributor to these air
quality problems in the U.S. is transportation. According to USEPA
(1999), about two-thirds of all CO emissions, and about one-third of all
NOx and VOC emissions, nationwide, are attributable to transportation
sources. Additionally, vehicles emit numerous toxic organic compounds,
some of which are carcinogenic, including benzene, 1,3-butadiene,
formaldehyde, ethyl benzene, methyl t-butyl ether (MTBE), hexane,
acetaldehyde, styrene, toluene, and xylene. And, for these specific
substances, highway vehicles are responsible about for one-quarter to
one-half of total U.S. emissions, depending upon the pollutant (USEPA,
2000, 1996a). In addition, diesel-powered vehicles emit particulates
comprised of numerous poly-cyclic and poly-aromatic hydrocarbons that
are potent carcinogens, as well as ultra-fine particles that that are
respiratory irritants (USEPA, 2000). Finally, the combustion of fossil
fuels results in carbon dioxide and other greenhouse gas emissions; and,
as of 1993, highway vehicles were responsible for about 23 percent of
anthropogenic carbon dioxide emissions in the U.S. (USEPA, 1996a).

There has been substantial research investigating vehicular emissions,
which are widely known to be a function of modal conditions (e.g.,
Hothersall and Salter, 1977). Specifically, emission rates are a
function of vehicle speed, engine loading (power output), rate of
acceleration or deceleration, etc., as well as mechanical factors such
as carburetion and vehicle maintenance (TRB, 1995). Significant
emissions also occur during engine starts as well as engine idling
(CARB, 2000, 1998, 1996).

The environmental impacts of transportation are even more significant
when they are examined on a life-cycle basis. Environmental life-cycle
analysis (LCA) is a systematic approach and set of methods and
techniques for the identification and assessment of environmental
impacts and consequences over the complete life cycle of a product or
process. The Society of Environmental Toxicology and Chemistry (SETAC,
1993, 1991) is generally credited for the current LCA methodological
framework; and, recent ISO standards (ISO 14040 et seq.) have further
formalized LCA. Moreover, the use of LCA to properly identify and
characterize the environ-mental impacts and consequences of a product,
process, or activity is recommended by USEPA (e.g., Keoleian and
Menerey, 1994, 1993). In the case of transportation vehicles, for
example, life-cycle impacts include not only those due to operation
(e.g., tailpipe emissions), but also those due to vehicle production,
the production of components and materials used in vehicle maintenance
as well as the maintenance activity itself, and the impacts due to the
"fuel cycle"---the extraction, refining, and distribution of motor
fuels---to name just a few. And, the impacts in these other life-cycle
stages may be significant. For example, DeLuchi (1993, 1991) found that
VOC, NO2, and SO2 emissions from the "fuel cycle" to be comparable to
those from the tailpipe on a normalized or "per mile" basis. Highly
insightful discussions of the life-cycle stages and impacts of
transportation systems are provided by USEPA (1999, 1996a), Keoleian, et
al (1997), and Graedel and Allenby (1998). From these analyses, it is
clear that the reduction of transporta-tion environmental impacts
requires consideration of the impacts over all life-cycle stages.

[Vehicle Routing and Scheduling with Environmental
Considerations]{.underline}

There has been extensive prior research investigating and modeling the
environmental impacts, primarily emissions, of vehicle operation, due in
part to Clean Air Act requirements. More recently, primarily in the
context of Intelligent Transportation Systems (ITS), researchers have
developed combined traffic simulation/emissions models for more
accurately predicting vehicle emissions based on actual (simulated)
modal conditions. Descriptions of numerous traffic/ emissions models in
current use may be found in FHWA (1992); USEPA (1998); Barth and Norbeck
(1996, 1994); Feng, et al (1997); Shaheen, et al (1998); and Abdulhai,
et al (1999).

There has also been limited prior work in the area of multi-objective
network optimization, including that based on environmental impacts
(tailpipe emissions), utilizing the previous models. In general, this
research---including that of Tzeng and Chen (1993); Bededek (1995);
SWUTC (1996); Yu (1996); Feng (1996); Kim (1995); Shaheen, et al.
(1998); Benedek and Rilett (1998); Yu and Stewart (1995); and Johnston
and Rodier (1999)---has focused on optimization of vehicle routing based
on various traffic assignment principles and algorithms. That is,
individual vehicles (representing origin-destination pairs) were
assigned routings on simulated traffic networks so as to optimize
particular objective functions. However, the previous research has
generally been limited to optimization of specific pollutants (tailpipe
emissions) individually and has not considered impacts on a life-cycle
basis. More importantly, as Yu and Stewart have observed, there remains
a genuine need to develop optimization models and approaches based on "a
generalized cost function that includes both travel-time variables and
the environmental variables."

Insofar as the problem of fleet vehicle routing and scheduling as we
have described it, i.e., where environmental impacts are included among
the optimization objectives, we have found only isolated examples in the
literature of prior work in this area. One example is that of Eriksson,
et al. (1996), who considered the use and/or assignment of vehicles
(from among two types) for the delivery of newspapers, where they
identified and optimized criteria pollutant emissions on a partial
life-cycle basis. Thus, in this sense, their analysis may be considered
as a type of vehicle routing problem. There have also been numerous
projects, utilizing ambient air quality data and other ITS technologies,
to reroute traffic (either through automated traffic control or
provision of information to drivers) around intra-urban areas where
pollutant levels are high. (See, for example, Taylor and Herbert, 1993
and Sommerville and Bostock, 1994, respectively, for descriptions of the
Advanced Transportation Telematics and APOLLON projects in Europe and
Iwaoka, et al., 2000 and Yoshiura, et al., 1999 for a discussion of the
Universal Traffic Management Systems 21 in Japan.) We are not aware,
however, of any prior work that has provided a methodology and algorithm
for the scheduling of paratransit (or other fleet) vehicles based on the
joint optimization of cost, service, and environmental impact
objectives---in particular, where the latter are evaluated utilizing
life-cycle impact assessment (LCIA) methods.

[Problem Description and Solution Approach]{.underline}

The objective of our research is to develop and demonstrate a
methodological approach and vehicle routing/scheduling algorithm for the
joint optimization of paratransit system performance including
life-cycle (LCIA-based) environmental impacts (consequences). This would
allow, for example, the operator of such a system to operate it in a
manner that optimizes cost and service performance while simultaneously
minimizing the environmental consequences of operation. We demonstrate
the methodology through computer simulation of a paratransit system
operation, where the modeled system is loosely based on an ACCESS
Services (paratransit) provider in Los Angeles County. In order to
accomplish the research objective, several developments are required and
are listed below. The listing also provides a general outline of the
remainder of this paper. The developments are:

1\) Development of an environmental life-cycle model of paratransit
operation and a life-cycle inventory (LCI) of operational environmental
impacts as a function of vehicle itinerary (route/schedule) parameters;

2\) Identification and quantification of the consequences of these
impacts utilizing life-cycle impact assessment (LCIA) methods, as the
basis of optimization;

3\) Development of a multi-objective decision model with which to assess
the relative desirability of alternative itineraries;

4\) Translation of the decision model to an optimization model, and
modification of existing DAR routing/scheduling algorithm to include the
(previous) environmental consequences;

5\) Simulation of paratransit operation and the vehicle scheduling
algorithm.

[PARATRANSIT LIFE-CYCLE MODEL]{.underline}

We consider a hypothetical paratransit operation comprised of four
vehicle types, including a gasoline-powered "minivan," a CNG-powered
"minivan," and larger capacity "shuttle busses," gasoline- and
diesel-powered. We assume generic, 1998-2000 model-year "light duty" or
"medium duty" vehicles for which data is available. We utilize MacLean's
(1998) life-cycle model of an automobile as the basis for our life-cycle
model, although it is necessary to adapt it to the particular activity
being modeled. Notably, MacLean's LCI model combines process
impacts---vehicular emissions---with those determined using aggregated
(economy-wide) data, specifically, data from the Economic Input
Output-Life Cycle Assessment (EIO-LCA) model developed by Lester Lave
and colleagues at Carnegie Mellon University (Hendrickson, et al.,
1998).

In actual paratransit operation, environmental impacts (primarily
tailpipe emissions and fuel consumption) arise due to vehicle usage and
are a direct function of distance traveled. However, significant
operational (process) impacts also arise from other aspects of vehicle
operation including engine idling and engine starts. And, these latter
impacts are a function of the vehicle itinerary (i.e., vehicle
scheduling decisions), but are unrelated to the vehicle travel distance
(which is also a function of itinerary). The life-cycle model for the
paratransit operational process is shown in Figure 1. It should be noted
that when a life-cycle inventory (LCI) is developed for the process, LCI
impacts are allocated on a "per mile," "per engine start," and "per
minute idling" basis.

![](media/image2.wmf){width="4.182638888888889in"
height="3.1368055555555556in"}

Vehicle running emissions are modeled utilizing the California Air
Resource Board (CARB) (2000, 1998) EMFAC/Burden model. This is a
regional emissions inventory model; however, we run the model including
only vehicles (in the model's database) for Southern California for the
model years and generic vehicles noted before, and using the default
values for all of the other model inputs. It should be noted that the
results are based upon the model's modified Federal Test Protocol drive
cycle; i.e., taking into account different modal conditions. (This
allows us to simulate transit using constant "average" speed, while
still calculating emissions reflecting typical modal conditions.)
Additionally, it is well known that the VOCs of tailpipe emissions are
comprised of numerous toxins and carcinogens, such as benzene, toluene,
formaldehyde, 1,3-butadiene, acetaldehyde, and others. We utilize data
from the literature (e.g., USEPA, 2000; Winebrake and Deaton, 1999;
Black, et al., 1998; Carslaw and Fricker, 1995; McCormick, et al., 2000;
and Nylund and Lawson, 2000) to estimate these components of emissions
from gasoline- as well as CNG- and diesel-powered engines. Finally,
diesel emissions---in particular, the particulate and aerosol
component---are known to be comprised of potent carcinogens, mostly in
the form of poly-aromatic or poly-cyclic compounds. We differentiate
diesel particulates (denoted as DPM-10) from particulates emitted from
other sources (denoted as PM-10) in our model for this reason.

To estimate the impact (life-cycle inventories) for the other life-cycle
stages, we utilize the EIO-LCA model and database available from
Carnegie Mellon University, at the Green Design Initiative (2001)
website at http://www.eiolca.net. Environmental impacts determined by
the model include criteria pollutant, global-warming, and
ozone-depleting emissions; non-renewable energy consumption; base and
precious metal ore depletion; non-hazardous and RCRA waste generation;
and Toxic Release Inventory (TRI) emissions. In the case of the latter,
the Carnegie Mellon researchers devised an equivalency measure---based
on American Conference of Governmental and Industrial Hygienists (ACGIH)
Threshold Limit Values (TLVs) (Horvath, et al., 1995). The results of
our life-cycle inventory analysis, with impacts summed over all
life-cycle stages, are presented as Table 1 (where reported TRI
emissions are on a CMU-Equivalent Toxicity basis). Details concerning
the calculation and basis of these values are provided in Appendix A.

[LIFE-CYCLE IMPACT ASSESSMENT BASIS]{.underline}

From a decision-theoretic perspective (e.g., Keeney, 1992, 1988), it is
not the impacts (e.g., tailpipe pollutant emissions) per se that are the
basis for concern or the appropriate basis for optimization. Rather, it
is the consequences of these impacts---e.g., human health and ecological
damages---that are the basis for caring and should be the optimization
basis. This is also consistent with the overall SETAC (1993, 1991) LCA
framework, which provides for the following LCA steps:

• [Inventory]{.underline}. The development of a detailed listing of all
material and energy inputs and outputs, including quantities, having an
environmental impact;

• [Classification]{.underline}. Identification of indicator or impact
categories and assignment of inventory components to the impact
categories;

• [Characterization]{.underline}. Analysis of the impacts/impact
categories in terms of human health damage, ecological damage, and
resource depletion (end-point effects);

• [Valuation]{.underline}. Assignment of relative weights or priorities
to each of the end-point effects, allowing, in effect, a single "score"
to be calculated and used for prioritizing alternatives.

Additionally, the SETAC framework allows for LCA to be performed at
different levels of analysis, including loading (Level 1); equivalency
(Level 2); toxicity, persistence, and bio-accumulation (Level 3); and
exposure/effects assessment (Levels 4/5). Equivalency analysis
(sometimes called "mid-point" analysis) considers only impact categories
(e.g., global warming) and the potential to cause damage (e.g., global
warming potential). Exposure/effects analysis (sometimes called "damage
function" or "end-point" analysis) includes identification of the
cause-consequence chains and considers end-point damages (e.g., human
morbidity and mortality) caused by the impacts (categories) considered
in the analysis. (For future reference, we denote the former analyses as
providing measures of damage potential and the latter analyses as
providing measures of potential damage.) An informative overview of
current LCA and LCIA practice may be found in Curran (1996).

Within this overall framework, the classification, characterization, and
valuation of environ-mental consequences are performed in the life-cycle
impact assessment (LCIA) step of LCA. Recently, numerous LCIA
suites---including models, methods, databases, and, often, companion
software---for this purpose have appeared and are in common usage.
(Reviews of these are provided by Jensen, et al., 1997, and
Postlethwaite and de Oude, 1996.)

From both the practical and theoretical perspectives, there are many
contemporaneous issues associated with these LCIA methods, such as what
the results represent insofar as actual damages that may be accrued
(Owens, 1999, 1997a, b; Goedkoop and Spriensma, 2000a, b; Besnainou and
Coulon, 1996); which method is "best" for a particular application or
analysis, since the methods do not provide data for identical sets of
compounds ("stressors" in SETAC terminology) or end-point damages (e.g.,
Hertwich, et al., 1998; Notarnicola, et al., 1998); and the
decision-theoretic validity of the valuation "formulas" that are
prescribed by some of the methods (Miettinen and Hämäläinen, 1997;
Seppälä, 1998; and Seppälä and Hämäläinen, 2001). Because of issues such
as these, it has been suggested within the LCA technical community
(Bare, et al., 2000) that LCIA results based on multiple methods
(levels) of analysis might be used together to facilitate better, or, at
least, more informed decision-making. For example, an analysis by
Swanson, et al. (2000) found the damage indicators from several LCIA
methods and levels of analysis to be complementary in nature; and, the
use of data from multiple methods is intuitively appealing.

We address these issues in the next section of this paper, where we
develop a decision-theoretic model. For now, what is important to
understand is that the damage indicators (both mid-point and end-point)
provided by the previous LCIA methodologies provide performance measures
or attributes (representing environmental damages or consequences) for
use in our decision and optimization models. That is, attributes are
used to measure the levels of achievement of the stated objectives. We
first identify the specific LCIA methods to be used, along with unit
damage indicator values, for the stressors identified in the LCI (Table
1), and then consider their use as decision attributes. Finally, we use
the results of the decision model (in the next main section) as the
basis for specifying necessary weighting constants in the vehicle
routing and scheduling objective function.

[Selection of Proxy Attributes for Human Health and Ecological
Damages]{.underline}

Shown in Tables 2 and 3 are indicator values, for the stressors listed
in Table 1 (LCI), from several popular LCIA methods and/or sources: EPS
(Steen, 1999a, b); Eco-Indicator (Goedkoop and Spriensma, 2000a, b);
human and ecological toxicity potentials developed by Huijbregts, et al.
(2000), based on the Uniform System for Evaluation of Substances (USES)
LCIA model; and acidification and eutrophical potentials reported by
Huijbregts (1999a). Also included in the Tables are potentials
(equivalency factors) for global warming, photochemical oxidant
creation, and acidification (USEPA, 1996b; CML, 2001) as well as hazard
scores for human, aquatic, and terrestrial toxicity, based on USEPA's
(1994) hazard assessment methodology. The indicators were selected to
include both end-point and mid-point damages, i.e., representing
potential damage and damage potential, as these terms were defined
previously, chosen as representative of LCA methods in current, popular
use. While the final form and appearance of the decision model(s) we
develop are predicated on the indicators selected, we point out that
other indicators could have been utilized just as well. That is, our
purpose is to provide a methodological approach for the construction and
evaluation of decision models utilizing indicators from multiple LCIA
methods as opposed to a prescription for a specific model.

Several important points should be noted before we proceed further.
First, the values shown in the Tables, in particular, for end-point
indicators such as those from the EPS and Eco-Indicator methods, are
unit values and are the "raw" indicator values provided by the
methodologies before application of the methodologies' weighting or
normalization factors. We develop our own weighting factors for the
decision model that we develop, next. Second, as explained in the notes
accompanying the Tables, we have combined the various EPS human
morbidity and mortality indicators into a single constructed attribute
"Calculated Disability-Adjusted Life-Years" (CDALYs) following an
approach developed by Murray and Lopez (1996, reported in Goedkoop and
Spriensma, 2000a). Similarly, we combined the various EPS indicators for
(crop, wood, fish/meat) productive capacity losses into a similar
constructed attribute "Productive Capacity Losses." We did this at this
point as a matter of convenience and based on assumed decision-maker
preferences. However, as seen in the decision model presented in the
next section, we would have had to perform such aggregation at some
other stage of the decision model evaluation if we had not done so here.
(For a discussion of constructed attributes, their use in decision
analysis, and their specification and evaluation, see Keeney, 1992.)
Third, we follow Owens' (1999, 1997a, b) and Besnainou and Coulon's
(1996) view that the damage indicators provided by the previous LCIA
methods provide performance indicators, albeit useful for comparative
analyses, rather than precise predictions of actual damages that will be
accrued. As such, following Keeney's terminology, decision attributes
defined based on these indicators are proxy attributes. Finally, it
might be noticed that the stressors identified in Table 1 include
certain resource consumptions (e.g., base metal) and other impacts
(e.g., RCRA and solid wastes) for which data is not provided in Tables 2
and 3. The reason for this, which will be seen later, is that we use
these impacts and quantities directly in the decision model; and, this
is also why we have focused our attention on human health and ecological
damages exclusively up to this point.

[DECISION-THEORETIC BASIS AND MODEL]{.underline}

Because of the underlying differences and limitations in the LCIA
methods above, we wish to utilize the data (damage indicators) from
multiple methods and levels of analysis in our decision model, as
suggested by Bare, et al. (2000). And, we develop a decision model
utilizing data from multiple LCIA methods based on decision-theoretic
principles. We note, however, that our objective is a *decision model*
utilizing various LCIA damage indicators and not the de facto synthesis
of a new LCIA *damage assessment model*. That is, we do not wish to
alter the various methods' impact categories, damage functions and
indicators, and internal stressor and damage allocations.

The decision problem as described thus far is a classic formulation in
multi-objective multi-attribute (MOMA) decision analysis, where the
decision objectives include not only environ-mental damages but also
cost- and service-related objectives, which we add to the model later.
Numerous, theoretically rigorous methodologies such as utility theory
(e.g., Fishburn, 1970, 1964; Keeney and Raiffa) or T.L. Saaty's (1977)
analytic hierarchy process (AHP) are available for such problems (see,
also, Seppälä, et al., 2002.) For the problem at-hand, we assume a
typical decision-maker willing to trade off accomplishment of the
objectives above, consistent with current LCA practice. Moreover, the
valuation formulas of current LCIA methods such as EPS and Eco-Indicator
should be seen to be utility-based (e.g., Seppälä, 1998; Seppälä and
Hämäläinen, 2001). Thus, to maintain consistency with current LCA
practice and LCIA methods, we choose utility theory as the basis on
which to develop our decision model.

Unlike most other decision methods, multi-attribute utility theory,
based on the game theory of von Neumann and Morgenstern (1947), also
provides a rigorous treatment of decision-maker attitude toward risk
(i.e., probabilistic outcomes). (We follow the convention that "utility"
models describe preferences for outcomes that are probabilistic and
"value" models describe preferences for outcomes that are
deterministic.) A theoretical discussion of utility theory's axiomatic
basis may be found in Luce and Raiffa (1957). Because we are considering
the damage indicators provided by LCIA methods as proxy measures for
actual damages (where minimization of the latter is our true or
fundamental decision objective), we develop the decision model as a
utility model. We also assume a decision-maker who is risk-neutral, in
part, to maintain consistency with current LCIA methods. And, we assume
that the other requisite conditions for a valid utility function hold
(e.g., as described in Luce and Raiffa, 1957).

[Basic Decision Model]{.underline}

We follow Keeney's approach, overall, for the specification and
hierarchical structuring of fundamental decision objectives. Following
SETAC (1993, 1991), we specify the highest-level objectives as
minimization of Human Health Damage, Ecological Damage, and Resource
Depletion; and, we add the additional objective of minimization of Other
Impacts to address those impacts from Table 1 (e.g., solid and RCRA
wastes) for which consequence (damage) data is unavailable. As suggested
by Bare, et al. (2000), we consider both mid-point and end-point
indicators, i.e., damage potential and potential damage, for the human
health and ecological categories; and, we specify these as
sub-objectives. The basic decision model (objectives hierarchy) as
developed thus far is shown in Figure 2, where the relationship between
objectives and attributes (LCIA damage indicators from Tables 2 and 3)
is also shown. In the Figure, the w~i~'s are preference-based weighting
or scaling constants. Additionally, we have combined Huijbregts, et
al.'s (2000) various (USES-LCA-based) ecological toxic potential
indicators (from Table 3) into a single constructed attribute,
Eco-Toxicity Potential, following a procedure that we describe next.

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##### Figure 2. Basic Decision Model

[Aggregation of Proxy Attributes]{.underline}

From a theoretical perspective, there are two significant, related
issues that must be addressed in order to aggregate LCIA damage
indicators as decision attributes as implied in Figure 2. First,
decision-maker preferences must be assessed based on actual consequences
(Keeney, 1992), even though the damage indicators, as proxy attributes,
provide only an imprecise measure of them (e.g., Owens, 1999, 1997a, b).
Second, the underlying models from which the damage indicators are
derived are not identical and consider different intermediate impact
categories, damage functions, etc. That is, in order to combine damage
indicators (as proxy attributes) from multiple LCIA methods, it is
necessary to make *factual-based judgments* comparing the magnitude of
*actual* damages represented by the respective indicators, in
consideration of the methods' underlying damage models. Ordinarily, this
would not be a consideration in the combination of indicators from a
single LCIA method. In our decision methodology, we address both of
these issues; however, for brevity, we present only the highlights
(below) as well as the final result.

We use Huijbregts, et al.'s (2000) various ecological toxicity
potentials (Table 3)---specifically, their combination into a single
constructed attribute, Eco-Toxicity Potential---to illustrate our
overall methodological approach for aggregating proxy attributes with
the above considerations in mind. Keeney (1992) provides an illuminating
discussion of the problems associated with the use of proxy attributes,
in particular, the need for the decision-maker to make a combination of
factual-based judgments (pertaining to the levels of actual consequences
associated with the proxy values) and value-based judgments (concerning
the relative desirabilities of the actual consequences). This
combination of judgments is problematic according to Keeney. And, he
provides an approach wherein the judgments are decoupled and the
factual-based judgments are made on a probabilistic basis. While
Keeney's approach could be applied to the problem at-hand, we expect
many decision-makers would have difficulty elucidating the required
probability distributions. Moreover, we feel the imprecision that is
associated with LCIA damage indicators as predictors of actual damages
is more aptly treated as *vagueness* than as probabilistic uncertain-ty.
Specifically, we utilize (fuzzy) linguistic variables to represent the
actual consequences as *possible*, rather than probable, outcomes, based
on Zadeh's (1978) representation of fuzzy sets as *possibility
distributions*, where we also implicitly assume that the requisite von
Neumann and Morgenstern axioms concerning probabilistic outcomes hold
for possibilistic outcomes, as well.

Our overall procedure is illustrated in Figure 3; however, we note again
that this procedure is also utilized in other aggregation steps when the
decision model is evaluated. We calculate the [unit damage
indicator]{.underline}, Ecological Toxicity Potential (USES-ETP),
denoted as D~ij~, value for each substance i listed in the LCI (Table
1), as

> ***D***~ij~ = ∑~k~ \[(w~k~ ***b***~k~ D~ijk~) / (∑~k~
> w~k~***b***~k~)\], (1)

where w~k~ has already been normalized. The D~ijk~'s are the substance-
and compartment-specific USES-LCA unit damage indicators (listed in
Table 2). (Notationally, the subscript "j" is used to identify damage
indicators and associated decision attributes; if USES-ETP were the only
damage indicator in the decision model, there would be no need for the
subscript. And, the subscript "k" denotes impact categories or
compartments, e.g., marine sediment. Fuzzy quantities are indicated in
bold-italic typeface.)

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##### Figures 3. Model for Evaluation of Constructed Attributes with Value 

##### and Factual Judgments De-Coupled

Values of ***b***~k~ , representing factual judgments concerning the
magnitude of *actual* consequences associated with the
compartment-specific indicators, are represented using normal,
triangular fuzzy numbers representing linguistic variables. For example,
the decision-maker may compare *actual* consequences associated with
Huijbregts, et al.'s, specific potentials using linguistic variables
such as "much greater," "about the same," etc. (See Figure 4.) Further,
in Huijbregts, et al.'s methodology, toxicity potentials are calculated
based on a single reference substance (1,4-dichlorobenzene). In other
words, only one ***b***~k~ based on 1,4-dichlorobenze is assessed for
each damage compartment. Finally, following LCIA and utility theory
conventions, we assume that value-based judgments, comparing consequence
desirability and used to evaluate the w~k~ constants, can be made on a
scalar basis.

[Decision-Maker Preference Assumptions, Evaluation of Single-Attribute
Utility Functions, and Overall Utility Equation Forms]{.underline}

Before we can proceed to specification of the final decision model,
including aggregation of attributes based on damage indicators from
multiple LCIA methods, we address some prerequisite matters concerning
decision-maker preferences (assumptions) and resultant utility equation
forms. First, following the convention of current LCIA methods, we
assume that single-attribute (unidimensional) utility functions have a
constant rate of (utility) substitution; i.e.,

![](media/image5.wmf){width="3.7875in" height="2.8618055555555557in"}

Figure 4. Linguistic Variables for Damage Comparison

single-attribute utility functions are linear. For example, let D~j~
denote the value of (potential damage or damage attribute)
[attribute]{.underline} j. Then,

u(D~j~) = - \[D~j~ -- D~j(BEST)~\] / \[D~j(WORST)~ -- D~j(BEST)~\], (2)

where D~j(WORST)~ and D~j(BEST)~ denote the "worst" and "best" values of
attribute j, respectively, among the alternatives considered. Note that
we have defined the utility scale such that 0 is "best" and --1 (or
"about minus 1" in the case of fuzzy numbers) is "worst." However, in
our (paratransit scheduling) application we do not know the "best" and
"worst" values of D~j~ a priori. Instead, we define reference values
based on estimation of the best and worst possible scheduling scenarios.
We define D~j(BEST)~ = 0 and redesignate D~j(WORST)~ as D~jREF~. Then,
because of assumed linearity of the unidimensional utility function,

u(D~j~) = - D~j~ / D~jREF~. (3)

For an attribute based on a single LCIA methodology, we evaluate the
attribute following the methodology's convention. In general, attribute
(D~j~) values, representing "total" damage or damage potential of type
j, are calculated as:

D~j~ = ∑~i~ I~i~D~ij~ = ∑~i~ ∑~k~ I~i~D~ijk~, (4)

where I~i~ is the quantity of stressor i (from the LCI), D~ij~ is the
stressor-specific unit damage indicator for stressor i and attribute
(damage type) j, and D~ijk~ is the stressor-impact-specific unit damage
indicator if such is provided by the methodology. Here, in the case of
end-point or damage function LCIA methods (such as EPS and
Eco-Indicator), the allocation of stressor i over the modeled impact
categories and damages is performed by the methodology (and is reflected
in the unit damage values, to facilitate the previous type of
calculation); and, we do not alter these allocations. In the case of
attributes based on mid-point or damage potential indicators (e.g.,
global warming potential), we allocate the stressor quantity 100 percent
to [each]{.underline} applicable impact category following USEPA (1996b,
1994).

Utility theory provides for the combination of preferences for multiple
attributes (representing multiple objectives) into a single value as:

u(x~1~, x~2~, ..., x~n~) = f\[u~1~(x~1~), u~2~(x~2~), ..., u~n~(x~n~)\],
(5)

where the actual form of f\[u~i~(x~i~)\] is predicated upon whether
certain preference independence conditions (among attributes) are met.
In the case of utility functions, if the attributes X~i~ are additive
independent (which also implies mutual utility independence among
attributes), an additive utility decomposition form may be used, i.e.,

u(x~i~) = ∑~i~ w~i~ u~i~(x~i~), where ∑~i~ w~i~ =1. (6)

That is, the preference (level) for an alternative is the simple sum of
the appropriately scaled preference levels of each attribute comprising
the alternative. If attributes X~i~ are each mutually utility
independent (only), a multiplicative form may be used, i.e.,

Ku(x~1~, x~2~, ..., x~n~) + 1 = ∏~i~^n^ \[Kk~i~u~i~(x~i~) + 1\]. (7)

Both are special cases of the multi-linear utility function (see Keeney,
1992, for a proof),

u(x~1~, x~2~, ..., x~N~) = ∑~i=1~ k~i~u~i~(x~i~) + ∑~i=1~∑~j\>1~
k~ij~u~i~(x~i~)u~j~(x~j~) +

> ∑~i=1~∑~j\>i~∑~h\>j~ k~ijh~u~i~(x~i~)u~j~(x~j~)u~h~(x~h~) + ... (8)

Because of the large number of attributes for which preference
independence would have to be tested, we, instead, limit consideration
to the additive and multiplicative forms as recommended by Zeleny (1982)
and Keeney and Raiffa (1993), including the nesting of such forms within
a larger overall model, as these forms have been shown to provide robust
representations of decision-maker preferences. As a consequence, we
assume attributes to be either additive or mutually utility independent
(only).

From the above discussion and the objectives structure of Figure 2, our
intended direction may be inferred. Namely, let the following denote
decision sub-objectives (with associated attributes):

H ≡ Human Health Damage

E ≡ Ecological Damage

R ≡ Resource Depletion

O ≡ Other Impacts

HD ≡ Human Health Potential Damages

HP ≡ Human Health Damage Potential

ED ≡ Ecological Potential Damages

EP ≡ Ecological Damage Potential.

Then, from the objectives structure in Figure 2, we define utility
functions such that:

u(itinerary) = f\[u~H~(H), u~E~(E), u~R~(R), u~O~(O)\], (9)

where

u~H~(H) = f\[u~HD~(HD), u~HP~(HP)\] (10)

u~E~(E) = f\[u~ED~(ED), u~EP~(EP)\], (11)

and where these individual utility functions are evaluated utilizing the
damage indicators (as attributes) shown in Figure 2.

Following current LCIA practice, we assume the highest-level attributes
of Equation 9 to be additive independent. In simple terms, additive
independence implies that the preference order for alternatives is
dependent only on the values and associated uncertainties of the
attributes individually and not in combination. (See Keeney, p. 134, for
a more precise and technical definition.) And, we also see this
assumption as reasonable for the aggregation of attributes
[within]{.underline} the individual damage potential and potential
damage utility functions, i.e., evaluation of u~HP~(HP), u~HD~(HD),
u~EP~(EP), and u~ED~(ED).

However, current LCIA practice does not provide guidance insofar as the
combination of *damage potential* and *potential damage* attributes.
Here, we provide for the possibility (although not necessity) that a
decision-maker's preference for the values of one set of attributes is
not independent of the values and uncertainties (technically, as
lotteries, or in this case, as possibility distributions) involving the
other set of attributes. And, we assume only the weaker condition of
mutual utility independence.

The result of these assumptions is that we may specify a decision model
of overall form:

u(itinerary) = w~H~ u~H~(H) + w~E~ u~E~(E) + w~R~ u~R~(R) + w~O~
u~O~(O), where (12)

u~H~(H) = w~HD~ u~HD~(HD) + w~HP~ u~HP~(HP) +

(1-w~HD~-w~HP~) u~HD~(HD)u~HP~(HP), (13)

u~E~(E) = w~ED~ u~ED~(ED) + w~EP~ u~EP~(EP) +

(1-w~ED~-w~EP~)u~ED~(ED)u~EP~(EP), (14)

where w~H~ + w~E~ + w~R~ + w~O~ = 1, all other terms are as defined
previously, and where equations for evaluation of u~R~(R), u~O~(O),
u~HD~(HD), u~HP~(HP), u~ED~(ED), and u~EP~(EP) remain to be defined.

Finally, we note one important point concerning the utility functions
above and assessment of scaling constants. Because of certain assumed
preference conditions (decision-maker risk neutrality and additive
independence among attributes within each of the HD, HP, ED, EP, R, and
O damage domains), utility functions and value functions (i.e., based on
deterministic outcomes) assessed over these domains must be coincident.
Specifically, since we are also assuming a decision-maker who is
[risk-neutral]{.underline}, where u(x) ∼ v(x), a utility function
(u\[x\]) assessed over an additive value function (v\[x\]) must also be
additive. This means that if we were assessing preferences for an actual
decision-maker, once we have determined that the decision-maker is
risk-neutral, we can assess preferences based on deterministic outcomes
(rather that lotteries involving uncertain outcomes) and induce utility
functions over the assumed (linear) value functions. Similarly, it
allows us to combine utility functions and value functions directly. Had
these preference conditions not been the case, we would have had to
assess utility functions based on uncertain outcomes or estimated the
functions from assessed value functions and assessment of the
decision-maker's risk tolerance. (Procedures for both may be found in
Keeney and Raiffa, 1993) Additionally, we note one important distinction
between value and utility functions: value functions provide cardinal
measures, while utility functions provide only ordinal measures, insofar
as strength of preference (Keeney, 1992). That is, differences of
utility values do not have cardinal meaning.

[Evaluation of End-Point Damage-Based Utility Functions, u~HD~(HD) and
u~ED~(ED)]{.underline}

As seen in Figure 2, we evaluate the end-point damage-based utility
functions, u~HD~(HD) and u~ED~(ED), based upon the damage indicators
provided by the EPS and Eco-Indicator LCIA methodologies. However, the
problem that arises is that the two methods, even though generally
considering the same stressors and impact categories, do not assign the
stressors identically to the same impact categories, as is more clearly
seen in Figures 5a and 5b. Hn.

Hence, the resultant indicators, e.g., for species loss (NEX and PDF,
respectively), are not comparable measures. In other words,
decision-maker factual judgment insofar as the *magnitude of actual
damages* represented by each proxy measure [for each
stressor]{.underline} is necessary. However, if we followed the
methodologies' conventions and aggregated damage indicators across
stressors (Equation 4) first before calculating utility values (Equation
3), the differences between the two methods would be masked by the
aggregation and there would be no basis on which to make the necessary
factual judgments.

A direct solution to this problem may be found by combining Equations 3
and 4. Specifically, it should be seen (in the case of damage indicators
from a single LCIA method) that

u(D~j~) = - \[∑~i~ I~i~D~ij~ / D~jREF~\] = ∑~i~ u(D~ij~), (15)

where u(D~ij~) = - I~i~D~ij~ / D~jREF~. and D~ij~ is the
stressor-specific unit damage indicator for stressor i, as before. This
is true because of the assumed linear single-attribute utility function,
the linear manner in which the methods combine stressor- and
impact-specific damage indicator values, and the way that D~jREF~ has
been defined. The quantity u(D~ij~) may be thought of as a "partial
utility value," attributable to stressor i, and where the utility value
(of an alternative) taking into account all stressors is the sum of the
partial utility values. Thus, to combine indicators from multiple (EPS
and Eco-Indicator) methods, we follow an approach similar to that
previously utilizing linguistic-based factual judgments. (We also adjust
the "spread" of the fuzzy variables to reflect the relative degree of
imprecision associated with the methodologies. In this case, because the
indicators and methods provide less imprecise indicators than before, we
use narrower "spreads.") Let A~Xl~ denote a decision attribute (X ∈ HD,
ED damage domains, l = 1, 2, ...) and a~Xli~ be the value of A~Xl~ for
stressor i. Then:

> ***u***~Xli~(a~Xli~) = - ∑~j~ {I~i~ ∑~k~ \[(D~ijk~)(***b***~Xlijk~)\]
> / D~j(REF)~}, ∀ D~j~ ∈ A~Xl~ (16)

where the ***b***~Xlijk~ values are normalized values representing
factual judgments as to the relative significance (in terms of *actual*
damages) associated with each damage indicator D~ijk~, evaluated for
each damage type j and stressor i. For example, Human Health Potential
Damage is evaluated based on one attribute A~HD1~ (l = 1), which, in
turn, is evaluated utilizing the EPS CDALY and Eco-Indicator DALY damage
indicators (e.g., D~j=1~ and D~j=2~). Values of ***b***~HD1ijk~ are
ascribed for each stressor i and impact category k (global warming,
human toxicity, oxidant creation; k=1, 2, 3). Assumed values of
***b***~HD1ijk~ are provided in Table 4 to illustrate the process.
Finally, the partial utility values are then aggregated over all
stressors as:

***u***~Xl~(a~Xl~) = ∑~i~ ***u***~Xli~(a~Xli~), for X = HD, ED. (17)

Values of u~HD~(HD) and u~HP~(HP) and then calculated simply as:

***u***~X~(X) = ∑~l~ w~Xl~***u***~Xl~(a~Xl~), l = 1, 2, ... ; ∑~l~ w~Xl~
= 1; for X=HD, ED. (18)

In the above calculations, it should be seen that we are aggregating
fuzzy quantities, in the calculation of utility values, as fuzzy
weighted averages, i.e., as ***r*** = (∑~l=1~^L^ ***w***~l~u~l~(A~l~) /
(∑~l=1~^L^ ***w***~l~). (See, for example, Klir and Yuan \[1995\].)

[Evaluation of Mid-Point Damage-Based Utility Functions, u~HP~(HP) and
u~EP~(EP)]{.underline}

The procedure for evaluation of the mid-point-based damage potential
utility functions, ***u***~HP~(HP) and ***u***~EP~(EP), is more or less
similar to the previous procedure with certain exceptions. From Figure
2, the two constructed attributes, Human Toxicity Damage Potential
(based on the damage indicators USES HTP and EPA-HHHRF) and Eco-toxicity
Damage Potential (based on the damage indicators USES-ETP, EPA-THRF, and
EPA-AHRF) are first evaluated. In the first case, because both
indicators provides measures of the same *type* of damage potential
(human health), only factual judgments are required and partial utility
values may be calculated using Equation 16. In the latter case, both
value- and factual-based judgments are required, since the indicators
represent different types of damage potentials. In this case:

***u***(a~Ej~) = - ∑~k~ {\[h~Ek~ ***e***~Ek~ (DP~jk~ / DP~jk(REF)~)\] /
\[∑~k~ h~Ek~ ***e***~Ek~\]}, (19)

where h~Ek~ and ***e***~Ek~ are value- and factual-based weighting
constants, respectively (e.g., as in Figure 3). Single-attribute utility
values for all other lowest-level attributes, u(a~Xj~), evaluated based
on a single damage indicator, may be evaluated following Equation 3.
Utility values for the decision attributes B~X~, where X = HP, EP, are
evaluated as

***u***~X~(B~X~) = ∑~j~ {\[c~Xj~ ***d***~Xj~ u(a~Xj~)\] / \[∑~j~ c~Xj~
***d***~Xj~\]}, (20)

where c~Xj~ and ***d***~Xj~ are value- and factual-based weighting
constants, respectively. (Values of c~Xj~ and h~Ek~ are normalized
because of the assumed linear-additive decomposition form. Normalized
values of ***e***~Ek~ and ***d***~Xj~ may also be used; however, it
should be seen in Equations 19-20 that it is the product, e.g., ∑~j~
c~Xj~ ***d***~Xj~, that is normalized in the calculation itself.)

The most important difference in this case is that the value- and
factual-based scaling constants are [not assessed for each stressor
i]{.underline}. Rather, they are ascribed based upon the impact
category, as it is assumed that the equivalency factors on which the
damage indicators are based take into account stressor-specific
differences.

[Evaluation of Resource Depletion and Other Impacts Utility Functions,
u~R~(R) and u~O~(O)]{.underline}

Utility values for Resource Depletion and Other Impacts objectives
(attributes) are calculated directly from the LCI quantities (Table 1).
In the case of the latter, we do this because of the lack of readily
available consequence data, and, in the case of the former, because of
the lack of consensus damage measures within the LCA community (e.g.,
Guinee and Heijungs, 1995; Hertwich, 1996). (However, this does not
obviate entirely the need for the decision-maker to consider the
consequences of these impacts, i.e., in the assessment of weighting
constants.) We also assume that the attributes comprising the Resource
Depletion and Other Impacts objectives to be additive (and mutually
utility) independent, allowing simple, linear-additive utility functions
to be defined for each. Following the previous nomenclature:

u~R~(R) = ∑~j~ w~Rj~ u(D~j~), ∀ D~j~ ∈ R, ∑~j~ w~Rj~ = 1 (21)

u~O~(O) = ∑~j~ w~Oj~ u(D~j~), ∀D~j~ ∈ O, ∑~j~ w~Oj~ = 1 (22)

u(D~j~) = -- (D~j~ / D~j(REF)~), D~j(REF)~ ≥ max\[D~j~\] among
alternatives (23)

D~j~ = ∑~i~ I~i~ D~ij~, ∀ D~j~ ∈ R, ∀ D~j~ ∈ O; D~ij~ = 1 if D~j~ ∈ {R,
O}, 0 otherwise. (24)

It should be seen in the above that D~ij~ in this case is a dummy
variable used to maintain consistency of nomenclature [and]{.underline}
to provide for the use of damage indicators other than stressor quantity
in the decision model, if desired. Finally, we note that the utility
functions above are, technically, *value functions*, as there is no
uncertainty of outcome involved.

[Evaluation of Value- (Preference-) Based Weighting
Constants]{.underline}

We assume that value- (preference-) based scaling constants,
representing the relative *desirabilities* of the attributes (as
consequences), can be assessed on a scalar basis, following LCIA and
utility theory practice. Techniques for the elicitation of
decision-maker preference may be found in Pöyhönen and Hämäläinen (1997)
as well as Keeney and Raiffa (1993). Importantly, these constants are
relative to, and must be assessed based upon, the range of outcomes
(i.e., the reference values) considered (Keeney, 1992). Also,
importantly, the scaling constants (w~k~'s) must be evaluated utilizing
preference, i.e., u(x) values as opposed to attribute (x) values, in
order to identify points of preference indifference. Keeney and Raiffa
(1993) provide a rigorous approach for the assessment of scaling
constants. Procedurally, their approach entails the comparison of
changes of attribute values (e.g., ∆x~1~ and ∆x~2~) and corresponding
changes of utility values, i.e., ∆u~1~(∆x~1~) and ∆u~2~(∆x~2~), to find
values of ∆x~1~ and ∆x~2~ such that ∆u~1~(∆x~1~) = ∆u~2~(∆x~2~) (from
which weighting constants can be calculated), where the consequence
scales are normalized scales.

[Calculation of Itinerary (Environmental) Utility Function Values and
Defuzzification of Results]{.underline}

For any itinerary, the transit distance, engine idling time, and number
of engine starts can be determined. (Engine idling and starts occur at
nodes, following an assumed paratransit service/ operational policy.
This is discussed later.) LCI impacts for an itinerary are calculated by
multiplying the previous quantities by the unit impact factors provided
in Table 1 for the applicable vehicle type. Damage indicator (attribute)
values are calculated by multiplying the resultant impact quantities by
the unit damage indicator values provided in Tables 2 and 3 (i.e.,
Equation 4). And, the itinerary utility value (Equation 12) is
calculated utilizing the utility relationships described in the Sections
4.2 through 4.6.

From the various equations, it should be seen that certain of the
calculated intermediate quantities are (normal, triangular) fuzzy
numbers. However, because fuzzy numbers cannot be ranked or ordered as
scalar numbers can, they must be defuzzified on some basis. As a general
rule, because the fuzzy number (set) contains distributional
information, we do not defuzzify calculated values until after the final
calculation, to avoid loss of this information. (For a discussion of
fuzzy arithmetic calculations, as well as defuzzification algorithms,
see, for example, Klir and Yuan, 1995.) For this purpose, we use the
common Center of Area (COA) defuzzification algorithm, which returns the
support (x- or abscissa) value of the centroid of the fuzzy possibility
distribution, i.e., x~c~ = (x~1~ + x~2~ + x~3~) / 3, where x~1~, x~2~,
and x~3~ are the x- values of the vortices. In the case of a triangular
fuzzy number (a, b, c), it should be seen that the x- values correspond
to the quantities a, b, and c, respectively.

[Decision Model Translation for Use in Optimization -- Calculation of
"Unit Partial Utility Values"]{.underline}

Using the decision model just presented, the utility value of an
itinerary (in terms of environ-mental consequences) may be calculated
based upon the transit distance, engine idling (minutes), and number of
engine starts resultant of the itinerary. In terms of the utility
calculation, these variables are independent variables (notwithstanding
the fact that there are a function of the itinerary itself). And, rather
than performing all of the previous calculations repeatedly, it is
desirable to transform the model from a decision model to an
optimization model, i.e., based on the previous independent variables:

u(itinerary) = f(Distance, Idling, Engine Starts, Vehicle Type). (25)

From the previous equations, it should readily be seen that if the
calculated single-attribute utility value for any damage indicator
(attribute D~j~) is --x for one mile of travel, it will be --2x for two
miles of travel, etc., because of the linearities that exist in the
calculation of damage values and single-attribute utility functions.
Similarly, the same result will hold for the LCI quantities expressed in
"per minute engine idle" and "per engine start" units. Further still,
the utility functions u~HD~(HD), u~HP~(HP), u~ED~(ED), u~EP~(EP),
U~R~(R), and U~O~(O) are also each evaluated utilizing linear-additive
combinations of the respective, single-attribute utility functions,
i.e., the u(D~j~)'s, from which they are evaluated. The point is that
these functions can be evaluated once for each vehicle type and each
vehicle operational unit, i.e., a mile of travel, a minute of engine
idling, and an engine start. And, Equations 12-14 (for calculating the
itinerary utility value) may then be evaluated directly from these
[unit]{.underline} quantities together with the known number of
respective units, i.e., miles of transit, minutes idling, and number of
engine starts. Illustrative values of these "unit partial utility
factors," calculated based upon values of factual- and value-based
weighting constants that we have assumed for a hypothetical
decision-maker, are provided in Table 5. Details of the calculation of
these values are provided in Appendix B. Values of assumed
decision-maker weighing constants may be found in Appendix C.

[PARATRANSIT OPERATION, MODELED SYSTEM AND MULTI-OBJECTIVE SCHEDULING
ALGORITHM, AND EXPERIMENTAL DESIGN]{.underline}

In general, paratransit service is provided "door-to-door"; that is, the
client is picked up at a requested location and transported to a desired
location. In this regard, service is similar to taxi service. However,
unlike taxi service, ridesharing (combining multiple, non-related
clients having non-identical origins and destinations) is allowed.
Moreover, increasing ridesharing is seen as key to improving
productivity (Dessouky and Adam, 1998a). Also in general, two types of
service requests are provided for: advance requests and same-day ("ASAP"
or "immediate") requests. Planned vehicle routes (itineraries) for
advance requests typically are determined in advance. However, the
planned routings must then be modified dynamically and in real-time to
accommodate same-day or "ASAP" requests. The latter task, called
dispatching, may be facilitated with the aid of certain ITS
technologies, such as automatic vehicle location (AVL) and geographic
information systems (GIS). Because of clients' physical disabilities,
specially equipped vehicles---in particular, those than can accommodate
wheelchair-bound patrons---are utilized. It should be noted, however,
that not all clients are necessarily wheelchair-bound, and that
paratransit fleets are often composed of multiple vehicle types for this
reason.

Paratransit providers must comply with certain standards, including
those prescribed in regulations as well as in contractual terms. For
example, the provider may be penalized (e.g., by the transportation
authority) if the provider refuses "appropriate" service requests or
misses agreed upon time windows (for example, +/- 15 or 20 minutes of
the agreed upon time). Conversely, the provider may receive performance
incentives based on service and economic performance, e.g., productivity
and utilization of resources. In practice, ride requests are assigned to
vehicles in a manner that minimizes an objective function comprised of
cost and service performance objectives. (See, for example,
Chira-Chavala, 1999 and Dessouky and Adam, 1998a.)

[Paratransit Vehicle Scheduling]{.underline}

The paratransit (DAR) optimization problem is a problem in combinatorial
optimization and is a combined vehicle routing and scheduling problem as
described before. Following the taxonomy of Psaraftis (1980) and Jaw, et
al. (1986), the paratransit problem of interest is "many-to-many"
(origins and destinations), multi-vehicle, and having time windows.
Specific cases of the problem include static (advance reservation)
scheduling and dynamic (immediate service) dispatching. There may also
be additional constraints, including service constraints (e.g., maximum
ride times), vehicle capacity, as well as precedence and other logical
constraints. Numerous algorithms for DAR routing and scheduling have
been developed and reported in the literature, generally for simplified
versions of the real-world problem. Overall, the algorithms (where time
windows are assumed) can be dichotomized based upon whether they are for
the static or dynamic case, for single- or multiple-vehicle systems, and
exact or heuristic.

Early research to develop scheduling algorithms was generally based on
the construction and solution of minimum spanning trees and/or Traveling
Salesman Problem (TSP) tours. Psaraftis (1983, 1980), for example,
provides both exact and heuristic solutions for the single vehicle case,
for both static and dynamic requests, where, in the case of the latter,
the tour was reoptimized every time a new request was received. Stein
(1978) provided an analytical examination of both single- and
multi-vehicle fleets, considering both the static and dynamic cases. He
proposes a two-step approach of clustering or partitioning of requests
followed by individual tour construction. However, his focus was on
optimal partitioning versus solution of the resultant TSP problem. More
recently, Ioachim, et al. (1995) modeled the problem as a pick-up and
delivery problem with time windows (PDPTW), which they solve in several
steps. However, their solution, too, involves the solution of a
resultant TSP problem, which they solve by a column generation method.

While exact solutions to the TSP problem are available (e.g., based on
Hamiltonian cycles), the problem is NP-hard, meaning that the number of
iterations that must be performed increases non-polynomially with the
size of the problem. For this reason, heuristic scheduling algorithms
are generally utilized in practice; and, two areas of development are of
particular note. The first is the development of "insertion" algorithms
(e.g., Jaw, et al., 1986; Madsen, et al., 1995; Toth and Vigo, 1997),
where requests are tentatively inserted into existing vehicles'
schedules on some heuristic basis, with the preferred insertion being
the one that minimizes the objective function of interest. These
algorithms can be used to construct initial vehicle itineraries for
static requests as well as to modify them dynamically. The second
development of note is the development of post-insertion optimization
procedures (e.g., Gendreau, et al., 1994, 1992), applicable to
itineraries constructed using insertion-type as well as other
algorithms.

[Modeled Paratransit System and Operation]{.underline}

In the modeled paratransit system, service is provided on a "24/7" basis
through the use of shifts. Modeled vehicles can accommodate certain
numbers of wheelchair and "regular" patrons, where the capacity of each
is fixed. And, the fleet is comprised of different types and sizes of
vehicles---with each vehicle type having specific capacities for each
type of patron as well as specific (non-identical) economic costs of
service and environmental impacts. Two types of requests are provided
for: "immediate" and "advance," where the latter are those received in
excess of five hours before the requested pick-up time. Advance requests
are scheduled at the beginning of the shift (the first shift on which
they could be serviced.) That is, "skeleton" itineraries are created
based on the advance requests. Immediate requests are scheduled when
received. In our model, transit speed is deterministic and is the same
for all vehicles (28 mph, the average transit speed in Los Angeles).
However, loading and unloading times are stochastic. It is assumed that
the position and status of all vehicles is known at all times; and, the
scheduling of immediate requests takes into account the vehicles' actual
statuses.

Time windows are applied to pick-up times (only); and, "maximum ride
time" is imposed as a feasibility constraint to prevent excessive ride
times (drop-off times) due to indirect routing. For a pickup, the
"on-time" window is defined as -x/+y minutes of the requested (assigned)
pick-up time, where the "late" window (y) is different for immediate and
advance requests. This is a "soft" window, meaning service will proceed
no matter how late the vehicle arrives. The "early" window, which is the
same for both types of requests, is a "hard" window. If a vehicle
arrives before the window (before --x minutes), the vehicle waits and
service begins at the "early" window, i.e., -x minutes of the requested
pick-up time. Monetary penalties are applied if the vehicle arrives at
the pick-up location early or late, i.e., outside of the on-time window.
In the modeled system, all vehicles originate and return to a central
depot. Overtime is not allowed; and, vehicles must return to the depot
by the end of the shift.

Service requests are generated randomly and are not known a priori.
Request parameters---including origin and destination locations,
requested pick-up times, call-in times, and number and type of patron
(wheelchair and non-wheelchair)---are random variables, where the
distributional parameters that are used are based on actual data
provided by ACCESS Services, Inc., and reported in Dessouky and Adam
(1998a, b). Experimental values of these and the previous parameters are
provided in Table 6.

Simulated vehicle operation is governed by certain service polices.
First, vehicles depart service nodes as soon as service
(loading/unloading) is completed and proceed to the next scheduled node,
unless the last service node is also the last node on the itinerary. In
this case, they wait at the last service node (which must be a
destination node), either until another request is received or until
such time that the vehicle could depart and return to the depot at the
end of the shift. Additionally, vehicles en route between service nodes
are not rerouted dynamically. Finally, insofar as engine idling and
starting, drivers allow the engine to idle during loading and unloading.
Similarly, drivers allow the engine to idle at pick-up nodes if the
vehicle must wait (because the vehicle is early) and there are
passengers already on-board. (This is done for passenger comfort, e.g.,
to allow operation of the vehicle's air conditioner or heater as well as
other devices.) On the other hand, if the vehicle arrives at a pick-up
node early and there are no passengers already on board, the driver is
assumed to turn off the vehicle's engine and restart it at the time
boarding begins. (These considerations do not apply to drop-off nodes,
as unloading begins immediately when the vehicle arrives at the node.)

[Simulation Model and Model Verification/Validation]{.underline}

To simulate operation of the modeled system, we developed an event-based
simulation program written entirely in Microsoft^®^ Visual Basic^TM^
6.0, where "events" include the scheduling of a service request and the
arrival of a vehicle at a service node (because of stochastic
loading/unloading times). In execution, the program constructs *planned*
itineraries, which are converted during the course of the simulation to
*executed* itineraries as a result of "events." That is, when an event
occurs, the affected vehicle's itinerary---specifically, planned times
subsequent to the event time---may be affected and are modified
accordingly. The model makes extensive use of data files, recording all
aspects of vehicle itineraries (times and node sequences) as well as
request-related service data. These files are used for the calculation
of simulation statistics and were used significantly for debugging and
model verification. Additionally, the program includes extensive error
traps, which were also used for model verification.

To validate the model and program, we compared the simulation results to
those of a similar model---based on the same overall request, service,
and experimental parameters and paratransit system---and insertion
algorithm previously reported by Dessouky and Adam (1998a). For
validation purposes, we ran the model with the environmental parameters
and values set to zero, and utilizing the same request data (file) as
Dessouky and Adam. We then compared the results based on the key
performance measures reported by Dessouky and Adam previously. (The
measures include those reported in Section 6.)

[Basic Real-Time Scheduling Heuristic]{.underline}

We adapt Dessouky and Adam's (1998a) scheduling objective function to
the modeled service policies and penalties described above.
Specifically, their algorithm is an implementation of Jaw, et al.'s
(1986) parallel insertion algorithm. And, based on the modeled system,
we define the objective function based on the weighted summation of
three itinerary-related costs: 1) transit cost (based on itinerary
distance), 2) lateness penalty (if the vehicle arrives at the pick-up
location after the on-time window), and 3) earliness penalty (if the
vehicle arrives at the pick-up location before the on-time window).

[Modification to Include Environmental Impacts]{.underline}

We next modify the previous heuristic to include environmental impacts.
Although we have not stated this explicitly before, we use utility
(theory) as the basis for aggregating economic costs and environmental
consequences, as they are in different units and there is no consensus
approach or data by which to monetize all environmental consequences.
Our objective function is of the form:

> maximize u(service of requests) = w~C~ u(economic cost) +
>
> w~E~ u(environmental impact). (27)

Let {R} be the set of requests for service to be scheduled and r~i~ be
the i^th^ request for service. The provision of service (for request
r~i~) incurs both an economic cost (denoted as CS~i~) and an
"environmental cost" (denoted as EC~i~). The scheduling objective,
generally speaking, is to minimize the combined values of CS~i~ and
EC~i~ over {R}, i.e., maximize ∑~i∈R~ u(CS~i~, EC~i~). (The utility
values are calculated as *disutility*, i.e., negative values; thus, the
objective is to maximize these values.)

Applying the same (additive independence) preference assumptions as
before, the objective is:

maximize ∑~i∈R~ u(CS~i~, EC~i~) = ∑~i∈R~ \[w~CS~u(CS~i~) +
w~EC~u(EC~i~)\]. (28)

Let CS~ij~\* denote the total economic cost of all vehicles' itineraries
(i.e., as Equation 26) after insertion of r~i~ into vehicle j's
itinerary; and let EC~ij~\* denote the environmental system "cost" of
all vehicles' itineraries after insertion of r~i~ into vehicle j's
itinerary. The basis for evaluation of EC~ij~\* and u(EC~ij~\*) was
discussed earlier. We calculate u(CS~ij~\*) also utilizing reference
values as before, i.e., u(CS~ij~\*) = - CS~ij~\* / CS~REF~, where
CS~REF~ is the estimated "worst" system cost for the operational period.

An *exact* solution to this problem would require that either all r~i~
were known a priori or that all vehicles' itineraries were reoptimized
after each new request was received. And, since neither are feasible or
practical, our optimization is heuristic and based on optimizing each
request individually:

maximize u(CS~ij~\*, EC~ij~\*) = maximize \[w~CS~u(CS~ij~\*) +

j j

w~EC~u(EC~ij~\*)\] for ∀r~i~∈{R}. (29)

Finally, before leaving this topic, we note one additional point that
was alluded to earlier. We assume that u*tility* functions have only
ordinal quality, even though under certain circumstances *value*
functions, having cardinal quality, could be induced as described
earlier. And, we do this so that our methodology is not predicated on
any particular preference condition, i.e., decision-maker risk
neutrality. Because of this, we cannot evaluate insertion costs (as
utility values) on a marginal basis. Moreover, because the environmental
utility function is non-linear and utility values are relative to the
scale on which consequences are evaluated, the alternative that is
"best" based on individual vehicle itinerary environmental impacts and
associated scales may not, necessarily, be the "best" alternative when
evaluated based upon system-wide environmental impacts and scales. And,
it is the system-wide impacts of operation, rather than the impacts of
any particular vehicle, that is the basis for caring, i.e., the
preference basis. Thus, we determine the "best" insertion based on
"total system" utility value, evaluated including all in-service
vehicles and itineraries, for each request scheduled.

[Experimental Design]{.underline}

Values of experimental and other cost/service parameters are provided in
Table 6; and, we only briefly discuss the experimental design here in
terms of its purpose and overall strategy. Our primary purpose is to
demonstrate that, through our methodology and the consideration of
environmental parameters in the vehicle routing and scheduling process
(i.e., algorithm), the overall environmental impacts of the operation
can be substantially reduced. Additionally, we would like to demonstrate
that this can be accomplished without equally substantial increases in
operating "cost"---which we measure in units of utility as well as
dollars and travel distance.

Because the system is stochastic and the variables used to measure
system performance are random variables, we utilize the *method of
independent replications* (e.g., Law and Kelton, 1991; Pritsker and
O'Reilly, 1999) to reduce the variance of the simulation results. In the
simulation program itself, because of the way that service requests are
generated and the way the vehicle-shifts are accounted for, the
transient effects that would be otherwise be expected to occur at system
(simulation) start-up and shut-down have been eliminated. This is to
say, we simulate paratransit operation as a *terminating* system; and,
we can replicate single 24-hour operating periods with minimal transient
effects that would affect the outcome.

We consider several fleet composition scenarios, where the fleet is
comprised of at least two or more vehicle types (from the types in Table
1). And, we also consider the case of a homogeneous fleet. For each
scenario, we compare the results---in terms of "cost" and environmental
impact---based on scheduling using our algorithm versus those where only
economic costs are considered (as in current paratransit scheduling
algorithms). We also simulate various levels of system loading (by
adjusting the number of available vehicles, since the number of requests
per period is constant). Specifically, we would expect to find greater
environmental improvement in a system having "surplus" vehicles
(including "environmentally friendlier" ones) available. And, we also
investigate the effect of varying the weighting constants in the
objective function (Equation 29). All scenarios utilize the same sets of
service requests.

[EXPERIMENTAL RESULTS]{.underline}

Simulation results, for the fleet compositions and fleet sizes
(representing different levels of system loading) simulated, are
provided in Tables 7 through 11. In the tables, the first row of each
composition-size combination (shown in boldface) represents the
"baseline," that is, based on the scheduling algorithm (objective
function) considering only economic costs. And, the rows immediately
below each "baseline" case are results based on the new algorithm
including environmental impact (Equation 29). We first consider the
effects of the new algorithm in terms of service performance and then in
terms of cost and environmental performance.

As seen in Table 7, together with the vehicle utilization results from
Table 9, the three loading levels simulated represent cases of surplus
capacity (surplus vehicles available), adequate capacity (all or most
available vehicles utilized), and capacity shortage (unscheduled
requests). It should also be observed that ridesharing (defined as the
number of requests served divided by the number of trip starts) remains
relatively constant over all cases and environmental weights, while
vehicle utilization increases as capacity relative to demand decreases.
In the case of the latter, this represents the elimination of "slack."
This is further evidenced by the trend of increasing mean pick-up delay
and decreasing on-time performance. However, taken together, we
interpret the constancy of ridesharing as indicating ridesharing is
primarily governed by the service and operational policies and
constraints, together with the spatial and temporal distribution of
requests, rather than by other factors such as capacity. Overall, it
should be seen from Table 7 that the effect of increasing environmental
weight in the objective function is to increase pick-up delays and
decrease on-time performance.

The effects of the new algorithm in terms of cost and environmental
performance may be seen in Table 8, as well as in Tables 10 and 11
comparing life-cycle environmental impacts. (From the regulatory
perspective, in particular for Southern California, the criteria and
other pollutant air emissions \[Tables 10a and 11\] represent the most
significant impacts identified in the LCI \[Table 1\]. Moreover, when
examined by life-cycle stage, up to one-half or more of the total
life-cycle emissions, depending upon pollutant, are attributable to
vehicle operation, service and maintenance, and fuel refining and
distribution---all of which would be expected to occur in the Southern
California region.) From Table 8, it should be immediately seen that the
most significant improvement in terms of environmental impact (as
utility value) relative to the "baseline"---both alone and relative to
marginal cost increase---occurs at the smallest environmental weighting
factor. That is, while further environmental improvement may (or may
not) be possible, it comes with increasing marginal cost. Moreover, from
Table 7, the service impacts are the least affected. Thus, we believe
many decision-makers would find this case (w~ENV~=0.125) to represent
the best marginal "trade-off." And, we consider only this case in the
remaining discussion.

Overall, the greatest environmental improvement (in terms of utility
value and specific pollutants) is seen to occur in Case I, the
heterogeneous fleet comprised of four types of vehicles. (This is also
our primary case of interest.) And, improvement occurs at all three
levels of system loading. For example, in the "best" (surplus vehicle)
case, as measured in utility values, environmental performance is
improved by about 33 percent while cost is increased by only about 4
percent. However, all Case I improvements (considering only the
"baseline" and w~ENV~=0.125 cases and based on utility value) are
statistically significant at the 95 percent (α=0.05) confidence
level.^(1,\ 2)^ Moreover, for this case, the apparent, slight cost
increases for the first two loading levels are not statistically
significant at the same confidence level.

Environmental improvements (as utility value) are also seen to result in
Case II (heterogeneous fleet comprised of two vehicle types) at all
system loading levels. And, all improvements are statistically
significant at the 95 percent confidence level. (See Notes 1 and 2.)
Finally, for the homogeneous fleet case (Case III), while Table 8
indicates very slight environmental (utility value) improvement at all
three system loading levels, the improvement is not statistically
significant.

Insights into the scheduling effects of the new algorithm may be
obtained from the data in Table 9, where the most obvious effect is the
shifting of vehicle selection, i.e., from "dirtier" to "cleaner"
vehicles. And, this is seen to occur (in the heterogeneous fleet cases)
at all system loading levels. Additionally, it should be seen that
average distance and total number of vehicles utilized appear to
decrease with increasing environmental objective weight---up to a
certain point. This would be expected to be associated with increasing
pick-up delays; and, this is seen to occur from Table 7. Finally, the
number of engine starts and controllable (waiting) engine idling also
appear to decrease slightly with increasing environmental objective
weight.

\_\_\_\_\_\_\_\_\_\_\_\_

\(1\) We calculate the confidence interval for ξ = μ~1~ - μ~2~, i.e.,
the difference of means, where μ~j~ ≈ E(X~j~). However, in our
simulation, we used the same sets of requests for each simulated case;
and X~1j~ and X~2j~ would, therefore, not be expected to be independent.
(However, n~1~ = n~2~.) Because of this, we use the "standard" paired-t
confidence interval, defining Z~j~ = X~1j~ -- X~2j~, where the Z~j~'s
are assumed to be IID. (We calculate Z~j~ using the results of
individual replications, which are not reported in this paper, where
X~1j~ is the "baseline" case where w~ENV~ =0 and X~2j~ is the case where
w~ENV~ =0.125.) Then, E(Z~j~) = ξ. And, the 100(1-α) confidence interval
for Z~MEAN~ is Z~MEAN~ ± t~n-1,\ 1-α/2~ \[Var(Z~MEAN~)\]^½^, where
Var(Z~MEAN~) = {∑~j=1~^J^ \[Z~j~ -- Z~MEAN~\]^2^ }/ n(n-1). (See, for
example, Law and Kelton.) That is, we are relying on the Central Limit
Theorem to imply that the coverage probability will be near 1-  α.
However, according to Law and Kelton, the parametric approach is robust
in this case, as any skewness in the underlying distributions will be
eliminated upon subtraction. And, finally, we make the claim that
differences in environmental performance (as utility value) are
statistically significant if zero does not fall within the confidence
interval. The calculated 95 percent confidence intervals for ξ, for the
three cases (I, II, III) and fleet sizes, are:\
\
[Case]{.underline} [Variable]{.underline} [210 Veh]{.underline}. [180
Veh]{.underline}. [150 Veh]{.underline}.

I u(env) \[0.1399, 0.1626\] \[0.0676, 0.0835\] \[0.0274, 0.0356\]

I u(cost) \[-0.0118, -0.0053\] \[-0.0098, -0.0038\] \[-0.0092, 0.0117\]

II u(env) \[0.0123, 0.0218\] \[0.0050, 0.0108\] \[0.0013, 0.0055\]

II u(cost) \[-0.0080, -0.0007\] \[-0.0112, 0.0004\] \[-0.0230, 0.0100\]

III u(env) \[-0.0018, 0.0065\] \[-0.0009, 0.0047\] \[-0.0025, 0.0027\]

III u(cost) \[-0.0074, 0.0000\] \[-0.0109, -0.0015\] \[-0.0119, 0.0067\]

(2) In order to perform the above comparisons, we must assume that
    differences of utility value have cardinal meaning, which is
    contrary to the point made earlier. In the case at-hand, utility
    functions do have cardinal meaning, as they were induced over valid
    value functions. However, in general, this may not be the case.
    Unfortunately, the only other way around this dilemma would be to
    calculate differences based on absolute quantities, i.e., pollutant
    emissions individually. We did this for the case of NO~x~ emissions,
    because these emissions are a concern (precursor to smog and ozone
    formation) and we assume them to be "representative." And, we
    calculated paired-t confidence intervals as described in Note 1. We
    found the differences (e.g., Tables 10 and 11) to be statistically
    significant for all Case I and Case II fleet size scenarios.
    Differences for Case III were found not to be statistically
    significant except for the 210 vehicle scenario.

[CONCLUSIONS AND RECOMMENDATIONS]{.underline}

In this research, we developed a methodology for the combined routing
and scheduling of fleet vehicles where environmental impacts, assessed
using environmental life-cycle impact assessment (LCIA) methods, have
been included in the scheduling algorithm and optimization objective
function. And, we demonstrated the methodology for a demand-responsive
("Dial-a-Ride" or paratransit) transit application, where both vehicle
cost and environmental impact parameters were assumed based upon generic
classes of vehicles and literature data. Through simulation, we showed
that substantial environmental performance improvements (emissions
reductions) can be achieved for heterogeneous fleets, at various loading
levels, with only minimal negative impacts on operational cost and
service performance, which was our primary objective. (In the case of a
homogeneous fleet, the environmental improvements were minimal and not
statistically significant.) While we considered only certain specific
heterogeneous fleet compositions, we believe the results are
generalizable to other heterogeneous fleet compositions that might have
been modeled based upon observed algorithm effects. Additionally, we
note that the specific results are based upon the arbitrary allocation
of vehicles (types) to the service shifts that were modeled. In other
words, on those shifts where additional vehicles were available (because
they were not on-duty at the time), further environmental impact
reductions may have been possible through different "mixes" of allocated
vehicle types. (It should be seen that there are trade-offs insofar as
vehicle operating cost, environmental impact, and capacity. And, the
"best" fleet composition is not, necessarily, a fleet comprised
exclusively of the lowest-cost or "cleanest" vehicles available.)

The environmental impacts of fleet vehicle operation are influenced by
many controllable and non-controllable variables and, of course, are a
function of parameters specific to the specific vehicles and vehicle
types comprising the fleet. One of these controllable variables is
vehicle assignment including routing and scheduling. And, while our
results can only be generalized so far, we believe they are adequate to
demonstrate, for the generalized heterogeneous fleet case, that
opportunities for reducing environmental impacts are available through
vehicle routing and scheduling decisions, and that environmental
performance can be jointly optimized with other operational (e.g., cost
and service) objectives. We also note that the emissions data we used
vary dramatically as a function of different driving patterns and
cycles. We did not study the changes in driving cycle in this study.

The South Coast Air Basin (including Los Angeles County) is the only
region in the country designated by USEPA as being in "extreme"
non-attainment with the Clean Air Act Ambient Air Quality Standard
(AAQS) for ozone. The area is also designated in the lesser category of
"serious" non-attainment with the AAQS for particulates (PM-10).
Moreover, a 1999 study by the SCAQMD (2002) found that up to 90 percent
of the carcinogenic risk in the South Coast Basin due to air quality is
attributable to mobile sources, primarily from diesel particulates and
air toxics. We have shown that, in certain circumstances, all of these
can potentially be reduced. (In the case of ozone, this is achieved
through reduction of its precursors, NO~x~ and VOCs.)

The methodology that we developed *could* be incorporated into existing
paratransit scheduling software, although to do so, we would recommend
the modifications discussed in the "Implementation" section. Moreover,
the SCAQMD, under Regulation XXII ("Mobile Source Emissions Mitigation
Programs"), provides funding for mobile source emissions mitigation
projects where the emissions reductions are "real," "surplus,"
"quantifiable," and meet other criteria. That is, it is within the realm
of possibility that SCAQMD funding might be obtainable by a paratransit
provider, in conjunction with a paratransit scheduling software
provider, to incorporate emissions reduction into paratransit scheduling
software.

[IMPLEMENTATION]{.underline}

We envision the benefits of this research to be as follows:

1)  We believe the primary benefit of this research is that it dispels
    the notion, for the case of a heterogeneous fleet, that
    environmental impacts (whether life-cycle based or based simply on
    criteria pollutant emissions) are solely a function of travel
    distance and are not affected by vehicle routing and scheduling
    decisions. While we see this research as being exploratory in some
    regards, as there has been virtually no prior research in this area,
    we hope that the results provide impetus to others to investigate
    potential applications, benefits, and limitations of the
    methodology.

2)  We developed the methodology taking into account life-cycle
    environmental impacts and utilizing rigorous decision-theoretic
    methods. As noted above, the methodology could be incorporated into
    existing paratransit scheduling software. To facilitate this, we
    suggest:

```{=html}
<!-- -->
```
a)  Limitation of impacts considered to criteria and air toxic
    pollutants, as these are of greatest concern in the South Coast Air
    Basin. (Additionally, global warming gases such as carbon dioxide
    could be included based on current legislation.) Moreover, while
    consideration of environmental impacts over all transportation
    life-cycle stages is required in order to achieve environmentally
    sustainable transportation systems, there are many jurisdictional
    and regulatory barriers that make this "systems approach" difficult
    to implement at the present. Therefore, we would suggest further
    limitation of impacts considered to tailpipe emissions.

b\) If limited to the above impacts, manufacturers' FTP certification
data should readily be available and allow specification of emissions
based on *actual* data for *actual* vehicle makes and models (e.g., as
user input).

c\) The purpose of the decision model developed herein was to facilitate
specification of weighting constants in the routing/scheduling objective
function for the environ-mental impacts, e.g., tailpipe emissions as a
function of vehicle itinerary, although this was perhaps obscured by the
fact that the objective function was specified based on utility rather
than emissions values. Nonetheless, an objective function could
alternatively have been specified of the form ∑~i~ w~i~I~i~, where I~i~
are the emissions of interest and w~i~ are preference-based weighting
constants. In the case of the latter, less formal and rigorous methods
are available for determining or specifying these; and, we suggest use
of these methods in any implementation of the methodology.

![](media/image6.wmf){width="5.347916666666666in"
height="3.870138888888889in"}

> Figure 5a. Combined Fundamental and Means-Ends Network for Health
> Damages

![](media/image7.wmf){width="5.059722222222222in"
height="3.667361111111111in"}

Figure 5b. Combined Fundamental and Means-Network for Ecological Damages

<table>
<colgroup>
<col style="width: 20%" />
<col style="width: 6%" />
<col style="width: 6%" />
<col style="width: 6%" />
<col style="width: 6%" />
<col style="width: 6%" />
<col style="width: 6%" />
<col style="width: 6%" />
<col style="width: 6%" />
<col style="width: 6%" />
<col style="width: 6%" />
<col style="width: 6%" />
<col style="width: 6%" />
</colgroup>
<tbody>
<tr class="odd">
<td colspan="13"><h4
id="table-1.-life-cycle-inventory-for-modeled-vehicle-types">Table 1.
Life-Cycle Inventory for Modeled Vehicle Types</h4></td>
</tr>
<tr class="even">
<td><h4 id="section-52"></h4>
<h4 id="impact"><em><u>Impact</u></em></h4></td>
<td colspan="3"><h4 id="section-53"></h4>
<h4 id="ld-gasoline-powered-minivan"><em><u>LD Gasoline-Powered
“Minivan”</u></em></h4></td>
<td colspan="3"><h4 id="section-54"></h4>
<h4 id="ld-cng-powered"><em><u>LD CNG-Powered</u></em></h4>
<p><u>“Minivan”</u></p></td>
<td colspan="3"><h4 id="md-gasoline-powered"><em><u>MD
Gasoline-Powered</u></em></h4>
<p><u>“Shuttle Bus”</u></p></td>
<td colspan="3"><h4 id="section-55"></h4>
<h4 id="md-diesel-powered"><em><u>MD Diesel-Powered</u></em></h4>
<p><u>“Shuttle Bus”</u></p></td>
</tr>
<tr class="odd">
<td></td>
<td>g/mile</td>
<td>g/min.</td>
<td>g/start</td>
<td>g/mile</td>
<td>g/min.</td>
<td>g/start</td>
<td>g/mile</td>
<td>g/min.</td>
<td>g/start</td>
<td>g/mile</td>
<td>g/min.</td>
<td>g/start</td>
</tr>
<tr class="even">
<td>NMOG (VOC)</td>
<td>0.4445</td>
<td>0.3041</td>
<td>0.2417</td>
<td>0.5600</td>
<td>0.0140</td>
<td>0.0092</td>
<td>0.6419</td>
<td>0.5189</td>
<td>0.5486</td>
<td>0.9862</td>
<td>0.1380</td>
<td>0.0940</td>
</tr>
<tr class="odd">
<td>Methane</td>
<td>0.0087</td>
<td>0.0526</td>
<td>0.0160</td>
<td>6.5400</td>
<td>0.3589</td>
<td>0.2480</td>
<td>0.0310</td>
<td>0.0749</td>
<td>0.0370</td>
<td>0.0176</td>
<td>0.0054</td>
<td>0.0037</td>
</tr>
<tr class="even">
<td>Formaldehyde</td>
<td>0.0013</td>
<td>0.0088</td>
<td>0.0067</td>
<td>0.0180</td>
<td>0.0099</td>
<td>0.0068</td>
<td>0.0060</td>
<td>0.1450</td>
<td>0.0168</td>
<td>0.0519</td>
<td>0.0160</td>
<td>0.0109</td>
</tr>
<tr class="odd">
<td>1,3-Butadiene</td>
<td>0.0003</td>
<td>0.0018</td>
<td>0.0013</td>
<td></td>
<td></td>
<td></td>
<td>0.0012</td>
<td>0.0029</td>
<td>0.0034</td>
<td>0.0021</td>
<td>0.0006</td>
<td>0.0004</td>
</tr>
<tr class="even">
<td>Acetaldehyde</td>
<td>0.0003</td>
<td>0.0018</td>
<td>0.0013</td>
<td>0.0020</td>
<td>0.0001</td>
<td>0.0001</td>
<td>0.0012</td>
<td>0.0029</td>
<td>0.0034</td>
<td>0.0104</td>
<td>0.0032</td>
<td>0.0022</td>
</tr>
<tr class="odd">
<td>Toluene</td>
<td>0.0060</td>
<td>0.0352</td>
<td>0.0276</td>
<td></td>
<td></td>
<td></td>
<td>0.0243</td>
<td>0.0587</td>
<td>0.0674</td>
<td>0.0041</td>
<td>0.0013</td>
<td>0.0009</td>
</tr>
<tr class="even">
<td>Benzene</td>
<td>0.0021</td>
<td>0.0123</td>
<td>0.0097</td>
<td></td>
<td></td>
<td></td>
<td>0.0085</td>
<td>0.0205</td>
<td>0.0237</td>
<td>0.0021</td>
<td>0.0006</td>
<td>0.0004</td>
</tr>
<tr class="odd">
<td>Methyl t-Butyl Ether</td>
<td>0.0042</td>
<td>0.0176</td>
<td>0.0149</td>
<td></td>
<td></td>
<td></td>
<td>0.0128</td>
<td>0.0309</td>
<td>0.0377</td>
<td></td>
<td></td>
<td></td>
</tr>
<tr class="even">
<td>SO<sub>x</sub> (SO<sub>2</sub>)</td>
<td>1.083</td>
<td>0.068</td>
<td>0.046</td>
<td>0.928</td>
<td>0.005</td>
<td>0.003</td>
<td>1.203</td>
<td>0.121</td>
<td>0.054</td>
<td>1.077</td>
<td>0.083</td>
<td>0.057</td>
</tr>
<tr class="odd">
<td>NO<sub>x</sub> (NO<sub>2</sub>)</td>
<td>1.088</td>
<td>0.189</td>
<td>0.408</td>
<td>1.714</td>
<td>0.145</td>
<td>0.0992</td>
<td>2.176</td>
<td>0.323</td>
<td>1.383</td>
<td>4.593</td>
<td>0.359</td>
<td>0.244</td>
</tr>
<tr class="even">
<td>CO</td>
<td>3.025</td>
<td>6.248</td>
<td>2.959</td>
<td>2.669</td>
<td>0.036</td>
<td>0.0249</td>
<td>6.048</td>
<td>12.403</td>
<td>9.244</td>
<td>2.018</td>
<td>0.332</td>
<td>16.042</td>
</tr>
<tr class="odd">
<td>GWP (CO<sub>2</sub> / CO<sub>2</sub>-equiv.)</td>
<td>867.2</td>
<td>154.0</td>
<td>104.3</td>
<td>936.2</td>
<td>32.3</td>
<td>22.2</td>
<td>1302.1</td>
<td>273.1</td>
<td>121.6</td>
<td>860.2</td>
<td>73.8</td>
<td>50.1</td>
</tr>
<tr class="even">
<td>PM-10</td>
<td>0.148</td>
<td>0.009</td>
<td>0.006</td>
<td>0.1466</td>
<td>0.023</td>
<td>0.0151</td>
<td>0.188</td>
<td>0.016</td>
<td>0.007</td>
<td>0.116</td>
<td>0.009</td>
<td>0.006</td>
</tr>
<tr class="odd">
<td>Diesel PM-10 (DPM-10)</td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td>0.0601</td>
<td>0.0230</td>
<td>0.0156</td>
</tr>
<tr class="even">
<td>TRI air emissions</td>
<td>0.042</td>
<td>≈ 0</td>
<td>≈ 0</td>
<td>0.044</td>
<td>≈ 0</td>
<td>≈ 0</td>
<td>0.038</td>
<td>0.001</td>
<td>≈ 0</td>
<td>0.041</td>
<td>≈ 0</td>
<td>≈ 0</td>
</tr>
<tr class="odd">
<td><p>Non-renew. energy use</p>
<p>(units in Mjoules)</p></td>
<td>7.488</td>
<td>0.982</td>
<td>0.668</td>
<td>7.024</td>
<td>0.069</td>
<td>0.047</td>
<td>13.135</td>
<td>1.760</td>
<td>0.786</td>
<td>6.968</td>
<td>1.050</td>
<td>0.710</td>
</tr>
<tr class="even">
<td><p>Fuel use (in gasoline eq.)</p>
<p>(Units in gallons)</p></td>
<td>0.0498</td>
<td>0.0125</td>
<td>0.0086</td>
<td>0.0454</td>
<td>0.0010</td>
<td>0.0007</td>
<td>0.0889</td>
<td>0.0223</td>
<td>0.0100</td>
<td>0.0387</td>
<td>0.0157</td>
<td>0.0107</td>
</tr>
<tr class="odd">
<td>Base-metal ore depletion</td>
<td>66.682</td>
<td>0.520</td>
<td>0.354</td>
<td>71.280</td>
<td>0.037</td>
<td>0.025</td>
<td>60.119</td>
<td>0.929</td>
<td>0.415</td>
<td>65.804</td>
<td>0.553</td>
<td>0.376</td>
</tr>
<tr class="even">
<td>Prec.-metal ore depletion</td>
<td>12.724</td>
<td>0.076</td>
<td>0.052</td>
<td>13.615</td>
<td>0.005</td>
<td>0.004</td>
<td>11.385</td>
<td>0..137</td>
<td>0.061</td>
<td>12.554</td>
<td>0.082</td>
<td>0.055</td>
</tr>
<tr class="odd">
<td>RCRA Wastes</td>
<td>1.466</td>
<td>0.051</td>
<td>0.035</td>
<td>1.525</td>
<td>0.004</td>
<td>0.002</td>
<td>1.468</td>
<td>0.092</td>
<td>0.041</td>
<td>1.428</td>
<td>0.055</td>
<td>0.037</td>
</tr>
<tr class="even">
<td>Non-recycled solid waste</td>
<td>4.800</td>
<td></td>
<td></td>
<td>5.560</td>
<td></td>
<td></td>
<td>5.190</td>
<td></td>
<td></td>
<td>6.82</td>
<td></td>
<td></td>
</tr>
</tbody>
</table>

+-------------+------+------+------+-------+-------+--------+--------+
| #####       |      |      |      |       |       |        |        |
| ## Table 2. |      |      |      |       |       |        |        |
|  LCIA Equiv |      |      |      |       |       |        |        |
| alency and  |      |      |      |       |       |        |        |
| Hazard Rank |      |      |      |       |       |        |        |
| ing Factors |      |      |      |       |       |        |        |
+-------------+------+------+------+-------+-------+--------+--------+
| [Stressor]{ | [GWP | [    | [Ac  | [Eutr | [     | [      | [Aq    |
| .underline} | (2)] | POCP | idif | ophic | Human | Terres | uatic] |
|             | {.un | (3)] | icat | ation | H     | trial] | {.unde |
|             | derl | {.un | ion] | Pote  | ealth | {.unde | rline} |
|             | ine} | derl | {.un | ntial | H     | rline} |        |
|             |      | ine} | derl | (     | azard |        | [      |
|             |      |      | ine} | 4)]{. | Ranki | [      | Hazard |
|             |      |      |      | under | ng]{. | Hazard | Ra     |
|             |      |      | [P   | line} | under | Ra     | nking] |
|             |      |      | oten |       | line} | nking] | {.unde |
|             |      |      | tial |       |       | {.unde | rline} |
|             |      |      | (4)] |       | [F    | rline} |        |
|             |      |      | {.un |       | actor |        | [      |
|             |      |      | derl |       | (     | [      | Factor |
|             |      |      | ine} |       | 1)]{. | Factor | (1)]   |
|             |      |      |      |       | under | (1)]   | {.unde |
|             |      |      |      |       | line} | {.unde | rline} |
|             |      |      |      |       |       | rline} |        |
+-------------+------+------+------+-------+-------+--------+--------+
| CO~2~       | 1    | 0    |      |       | 0     | 0      | 0      |
+-------------+------+------+------+-------+-------+--------+--------+
| CO          | 3    | 0    |      |       | 4.8   | 0      | 0      |
|             |      | .270 |      |       |       |        |        |
+-------------+------+------+------+-------+-------+--------+--------+
| NO~x~       | 0    | 0    | 0.7  | 1.0   | 12.3  | 0      | 0      |
|             |      | .028 |      |       |       |        |        |
+-------------+------+------+------+-------+-------+--------+--------+
| PM-10       | 0    | 0    |      |       | 0     | 0      | 0      |
+-------------+------+------+------+-------+-------+--------+--------+
| (NM)VOC     | 11   | 0.64 |      |       | 17.8  | 0.5    | 32.5   |
+-------------+------+------+------+-------+-------+--------+--------+
| SO~x~       | 0    | 0    | 1.0  |       | 3.6   | 0      | 0      |
|             |      | .048 |      |       |       |        |        |
+-------------+------+------+------+-------+-------+--------+--------+
| 1,          | 11   | 0.85 |      |       | 43.8  | 1.8    | 46.8   |
| 3-Butadiene |      |      |      |       |       |        |        |
+-------------+------+------+------+-------+-------+--------+--------+
| F           | 11   | 0.52 |      |       | 70.2  | 12.6   | 28.2   |
| ormaldehyde |      |      |      |       |       |        |        |
+-------------+------+------+------+-------+-------+--------+--------+
| Toluene     | 11   | 0.64 |      |       | 12.2  | 0      | 24.0   |
+-------------+------+------+------+-------+-------+--------+--------+
| Benzene     | 11   | 0.22 |      |       | 38.7  | 0      | 25.2   |
+-------------+------+------+------+-------+-------+--------+--------+
| A           | 11   | 0.64 |      |       | 27.0  | 3.3    | 19.5   |
| cetaldehyde |      |      |      |       |       |        |        |
+-------------+------+------+------+-------+-------+--------+--------+
| Methane     | 24.5 | 0    |      |       | 0     | 0      | 0      |
|             |      | .006 |      |       |       |        |        |
+-------------+------+------+------+-------+-------+--------+--------+
| Methyl      | 11   | 0    |      |       | 1.2   | 1.2    | 1.2    |
| t-Butyl     |      | .175 |      |       |       |        |        |
| Ether       |      |      |      |       |       |        |        |
| (MTBE)      |      |      |      |       |       |        |        |
+-------------+------+------+------+-------+-------+--------+--------+
| DPM-10      | 0    | 0    |      |       | 37.0  | 0      | 71.2   |
+-------------+------+------+------+-------+-------+--------+--------+
| \(1\)       |      |      |      |       |       |        |        |
| Hazard      |      |      |      |       |       |        |        |
| ranking     |      |      |      |       |       |        |        |
| values from |      |      |      |       |       |        |        |
| USEPA       |      |      |      |       |       |        |        |
| (1994).     |      |      |      |       |       |        |        |
| DPM-10      |      |      |      |       |       |        |        |
| value based |      |      |      |       |       |        |        |
| on          |      |      |      |       |       |        |        |
| anthracene. |      |      |      |       |       |        |        |
| VOC value   |      |      |      |       |       |        |        |
| based on    |      |      |      |       |       |        |        |
| xylene      |      |      |      |       |       |        |        |
| (mixed      |      |      |      |       |       |        |        |
| isomers).   |      |      |      |       |       |        |        |
| Values for  |      |      |      |       |       |        |        |
| CO, NO~x~,  |      |      |      |       |       |        |        |
| SO~x~\      |      |      |      |       |       |        |        |
| estimated   |      |      |      |       |       |        |        |
| on LC~50~.  |      |      |      |       |       |        |        |
|             |      |      |      |       |       |        |        |
| \(2\) GWP   |      |      |      |       |       |        |        |
| values      |      |      |      |       |       |        |        |
| taken from  |      |      |      |       |       |        |        |
| Steen       |      |      |      |       |       |        |        |
| (1999a).    |      |      |      |       |       |        |        |
|             |      |      |      |       |       |        |        |
| \(3\) POCP  |      |      |      |       |       |        |        |
| values      |      |      |      |       |       |        |        |
| taken from  |      |      |      |       |       |        |        |
| CML (2001). |      |      |      |       |       |        |        |
| VOC value   |      |      |      |       |       |        |        |
| based on    |      |      |      |       |       |        |        |
| toluene.    |      |      |      |       |       |        |        |
|             |      |      |      |       |       |        |        |
| \(4\)       |      |      |      |       |       |        |        |
| Ac          |      |      |      |       |       |        |        |
| idification |      |      |      |       |       |        |        |
| and         |      |      |      |       |       |        |        |
| eut         |      |      |      |       |       |        |        |
| rophication |      |      |      |       |       |        |        |
| values      |      |      |      |       |       |        |        |
| taken from  |      |      |      |       |       |        |        |
| Huijbregts  |      |      |      |       |       |        |        |
| (1999) and  |      |      |      |       |       |        |        |
| USEPA       |      |      |      |       |       |        |        |
| (1996b).    |      |      |      |       |       |        |        |
+-------------+------+------+------+-------+-------+--------+--------+

<table style="width:100%;">
<colgroup>
<col style="width: 10%" />
<col style="width: 9%" />
<col style="width: 9%" />
<col style="width: 10%" />
<col style="width: 9%" />
<col style="width: 10%" />
<col style="width: 10%" />
<col style="width: 10%" />
<col style="width: 10%" />
<col style="width: 10%" />
</colgroup>
<tbody>
<tr class="odd">
<td colspan="10"><strong>Table 3. LCIA Damage Function Indicators by
Impact Category</strong></td>
</tr>
<tr class="even">
<td><strong><u>Stressor</u></strong></td>
<td colspan="9"><strong><u>Impact Category and Indicator Type and
Value</u></strong></td>
</tr>
<tr class="odd">
<td rowspan="3"></td>
<td colspan="4" rowspan="2"><u>Global Warming</u></td>
<td colspan="5"><u>Human Toxicity</u></td>
</tr>
<tr class="even">
<td><u>Toxicity</u></td>
<td><p><u>Oxidant</u></p>
<p><u>Formation</u></p></td>
<td><p><u>Carcinogenic</u></p>
<p><u>Effects</u></p></td>
<td><p><u>Respiratory</u></p>
<p><u>Effects</u></p></td>
<td><p><u>Toxic</u></p>
<p><u>Potential</u></p></td>
</tr>
<tr class="odd">
<td>EPS-CDALY</td>
<td>Eco-DALY</td>
<td>EPS-Prod.Cap.</td>
<td>EPS-NEX</td>
<td>EPS-CDALY</td>
<td>EPS-CDALY</td>
<td>Eco-DALY</td>
<td>Eco-DALY</td>
<td>USES-HTP</td>
</tr>
<tr class="even">
<td>CO<sub>2</sub></td>
<td>1.30E-6</td>
<td>2.10E-7</td>
<td>-3.97E-2</td>
<td>1.26E-14</td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr class="odd">
<td>CO</td>
<td>3.91E-6</td>
<td></td>
<td>-4.05E-2</td>
<td>3.78E-14</td>
<td>1.44E-8</td>
<td></td>
<td></td>
<td>7.31E-7</td>
<td></td>
</tr>
<tr class="even">
<td>NOx</td>
<td>-4.34E-6</td>
<td></td>
<td>3.45E-3</td>
<td>-1.08E-13</td>
<td>1.43E-4</td>
<td>8.28E-8</td>
<td></td>
<td>8.91E-5</td>
<td>1.2E+0</td>
</tr>
<tr class="odd">
<td>PM-10</td>
<td>-4.34E-6</td>
<td></td>
<td>3.45E-3</td>
<td>-1.08E-13</td>
<td>5.42E-4</td>
<td></td>
<td></td>
<td>3.75E-4</td>
<td>9.6E-2</td>
</tr>
<tr class="even">
<td>(NM)VOC</td>
<td>1.14E-5</td>
<td></td>
<td>-1.21E-1</td>
<td>1.39E-13</td>
<td></td>
<td>7.63E-6</td>
<td></td>
<td>6.46E-7</td>
<td>4.3E-2</td>
</tr>
<tr class="odd">
<td>SOx</td>
<td>-1.23E-5</td>
<td></td>
<td>9.80E-3</td>
<td>-3.06E-13</td>
<td>3.72E-4</td>
<td></td>
<td></td>
<td>5.46E-5</td>
<td>3.1E-1</td>
</tr>
<tr class="even">
<td>1,3-Butadiene</td>
<td>1.43E-5</td>
<td></td>
<td>-1.26E-1</td>
<td>1.39E-13</td>
<td>8.66E-5</td>
<td>1.25E-5</td>
<td>1.58E-5</td>
<td>1.87E-6</td>
<td>2.2E+3</td>
</tr>
<tr class="odd">
<td>Formaldehyde</td>
<td>1.43E-5</td>
<td></td>
<td>-5.18E-1</td>
<td>1.39E-13</td>
<td>5.34E-5</td>
<td>7.10E-7</td>
<td>9.91E-7</td>
<td>1.11E-6</td>
<td>8.3E-1</td>
</tr>
<tr class="even">
<td>Toluene</td>
<td>1.14E-5</td>
<td></td>
<td>-1.21E-1</td>
<td>1.39E-13</td>
<td></td>
<td>5.56E-6</td>
<td></td>
<td>1.36E-6</td>
<td>3.3E-1</td>
</tr>
<tr class="odd">
<td>Benzene</td>
<td>1.43E-5</td>
<td></td>
<td>-1.31E-1</td>
<td>1.39E-13</td>
<td>2.11E-5</td>
<td>3.94E-6</td>
<td>2.50E-6</td>
<td>4.68E-7</td>
<td>1.9E+3</td>
</tr>
<tr class="even">
<td>Acetaldehyde</td>
<td>1.14E-5</td>
<td></td>
<td>-1.21E-1</td>
<td>1.39E-13</td>
<td></td>
<td>6.63E-6</td>
<td>2.16E-7</td>
<td>1.36E-6</td>
<td>4.3E-2</td>
</tr>
<tr class="odd">
<td>Methane</td>
<td>3.19E-5</td>
<td>4.40E-6</td>
<td>-9.45E-2</td>
<td>3.09E-13</td>
<td></td>
<td>8.73E-8</td>
<td></td>
<td>1.28E-8</td>
<td></td>
</tr>
<tr class="even">
<td>MTBE</td>
<td>1.14E-5</td>
<td></td>
<td>-1.21E-1</td>
<td>1.39E-13</td>
<td></td>
<td>3.60E-6</td>
<td></td>
<td>3.32E-7</td>
<td>4.3E-2</td>
</tr>
<tr class="odd">
<td>DPM-10</td>
<td>-4.34E-6</td>
<td></td>
<td>3.45E-3</td>
<td>-1.08E-13</td>
<td>6.80E-1</td>
<td></td>
<td>9.78E-6</td>
<td>7.00E-4</td>
<td>5.7E+5</td>
</tr>
<tr class="even">
<td colspan="10"><p>(1) All EPS, Eco-Indicator damage factors are the
“raw” factors, without normalization or application of weighting
factors.</p>
<p>(2) Shaded cells indicate the stressor is not assigned to the impact
category; i.e., the cell (indictor) value is zero.</p>
<p>(3) EPS values from Steen (1999a). Calculated disability-adjusted
life-years (CDALYs) calculated based on 1 YOLL = 1 CDALY, 1 person-year
severe</p>
<p>morbidity = 0.7 CDALY, 1 person-year morbidity = 0.4 CDALY, 1
person-year severe nuisance = 0.1 CDALY, and 1 person-year nuisance =
0.05 CDALY.</p>
<p>EPS productive capacity calculated as the (unweighted) sum of crop,
wood, and fish/meat productive capacity loss indicators.</p>
<p>(4) Eco-Indicator values from Goedkoop and Spriensma (2000a), based
on Egalitarian perspective.</p>
<p>(5) USES-LCA toxicity potentials from Huijbregts, et a.(2000).</p>
<p>(6) EPS values for (NM)VOC based on p-xylene. EPS values for MTBE
based on dimethylether.</p>
<p>(7) Diesel particulate matter values: EPS values for polyaromatic
compounds use for human health effects, PM-10 values used for other
effects.</p>
<p>USES-LCA values based on “carcinogenic PAHs.” Eco-Indicator values
based on “diesel soot” for carcinogenic effects and PM-2.5 for other
effects.</p>
<p>(8) USES-LCA values for (NM)VOC, acetaldehyde and MTBE estimated
based upon p-xylene.</p>
<p>(9) EPS damage factors for NO<sub>x</sub>, SO<sub>x</sub>, PM-10 and
DPM-10 for above impact categories are calculated from pathway-specific
characterization factors<br />
provided by Steen (1999a), as the reported, summed values combine
certain damages (factors) across the above impact categories.<br />
(10) All values based on emissions to air (as initial compartment). All
values in units per kg stressor.</p></td>
</tr>
</tbody>
</table>

<table>
<colgroup>
<col style="width: 11%" />
<col style="width: 12%" />
<col style="width: 2%" />
<col style="width: 12%" />
<col style="width: 2%" />
<col style="width: 8%" />
<col style="width: 6%" />
<col style="width: 6%" />
<col style="width: 8%" />
<col style="width: 3%" />
<col style="width: 11%" />
<col style="width: 1%" />
<col style="width: 13%" />
</colgroup>
<tbody>
<tr class="odd">
<td colspan="13"><strong>Table 3. LCIA Damage Function Indicators by
Impact Category (cont.)</strong></td>
</tr>
<tr class="even">
<td><strong><u>Stressor</u></strong></td>
<td colspan="12"><strong><u>Impact Category and Indicator Type and
Value</u></strong></td>
</tr>
<tr class="odd">
<td rowspan="2"></td>
<td colspan="12"><u>Eco-Toxicity</u></td>
</tr>
<tr class="even">
<td colspan="2"><p>USES-LCA</p>
<p>(FW Aq. Toxicity)</p></td>
<td colspan="2"><p>USES-LCA</p>
<p>(Mar. Aq. Toxicity)</p></td>
<td colspan="2"><p>USES-LCA</p>
<p>(FW Sed. Toxicity)</p></td>
<td colspan="2"><p>USES-LCA</p>
<p>(Mar. Sed. Toxicity)</p></td>
<td colspan="2"><p>USES-LCA</p>
<p>(Terrestrial Toxicity)</p></td>
<td colspan="2"><p>Eco-Indicator PDF</p>
<p>(Pot. Disapp. Fract.)</p></td>
</tr>
<tr class="odd">
<td>CO<sub>2</sub></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
</tr>
<tr class="even">
<td>CO</td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
</tr>
<tr class="odd">
<td>NOx</td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
</tr>
<tr class="even">
<td>PM-10</td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
</tr>
<tr class="odd">
<td>(NM)VOC</td>
<td colspan="2">6.1E-5</td>
<td colspan="2">6.1E-4</td>
<td colspan="2">3.7E-5</td>
<td colspan="2">3.8E-4</td>
<td colspan="2">5.3E-7</td>
<td colspan="2"></td>
</tr>
<tr class="even">
<td>SOx</td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
</tr>
<tr class="odd">
<td>1,3-Butadiene</td>
<td colspan="2">3.3E-7</td>
<td colspan="2">2.7E-6</td>
<td colspan="2">2.2E-7</td>
<td colspan="2">3.0E-6</td>
<td colspan="2">2.3E-8</td>
<td colspan="2"></td>
</tr>
<tr class="even">
<td>Formaldehyde</td>
<td colspan="2">8.3E+0</td>
<td colspan="2">1.6E+0</td>
<td colspan="2">4.5E+0</td>
<td colspan="2">1.5E+0</td>
<td colspan="2">9.4E-1</td>
<td colspan="2"></td>
</tr>
<tr class="odd">
<td>Toluene</td>
<td colspan="2">7.0E-5</td>
<td colspan="2">7.0E-4</td>
<td colspan="2">5.0E-5</td>
<td colspan="2">5.8E-4</td>
<td colspan="2">1.6E-5</td>
<td colspan="2">2.40E-4</td>
</tr>
<tr class="even">
<td>Benzene</td>
<td colspan="2">8.5E-5</td>
<td colspan="2">2.8E-3</td>
<td colspan="2">6.4E-5</td>
<td colspan="2">1.3E-3</td>
<td colspan="2">1.6E-5</td>
<td colspan="2">2.75E-3</td>
</tr>
<tr class="odd">
<td>Acetaldehyde</td>
<td colspan="2">6.1E-5</td>
<td colspan="2">6.1E-4</td>
<td colspan="2">3.7E-5</td>
<td colspan="2">3.8E-4</td>
<td colspan="2">5.3E-7</td>
<td colspan="2"></td>
</tr>
<tr class="even">
<td>Methane</td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
</tr>
<tr class="odd">
<td>MTBE</td>
<td colspan="2">6.1E-5</td>
<td colspan="2">6.1E-4</td>
<td colspan="2">3.7E-5</td>
<td colspan="2">3.8E-4</td>
<td colspan="2">5.3E-7</td>
<td colspan="2"></td>
</tr>
<tr class="even">
<td>DPM-10</td>
<td colspan="2">1.7E+2</td>
<td colspan="2">4.3E+3</td>
<td colspan="2">5.6E+2</td>
<td colspan="2">1.4E+4</td>
<td colspan="2">1.0E+0</td>
<td colspan="2">7.80E-4</td>
</tr>
<tr class="odd">
<td colspan="13"></td>
</tr>
<tr class="even">
<td rowspan="2"></td>
<td><u>Oxidant Formation</u></td>
<td colspan="6"><u>Acidification</u></td>
<td colspan="2"><u>N-Nutrification</u></td>
<td colspan="2"><u>Eutrophication</u></td>
<td><u>Acid. + Eutroph.</u></td>
</tr>
<tr class="odd">
<td>EPS–Prod. Cap.</td>
<td colspan="2">EPS–Base Cat.Cap.</td>
<td colspan="2">EPS–Prod. Cap.</td>
<td colspan="2">EPS – NEX</td>
<td colspan="2">EPS–Prod. Cap.</td>
<td colspan="2">EPS - NEX</td>
<td>Eco-Indicator PDF</td>
</tr>
<tr class="even">
<td>CO<sub>2</sub></td>
<td></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td></td>
</tr>
<tr class="odd">
<td>CO</td>
<td></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td></td>
</tr>
<tr class="even">
<td>NOx</td>
<td>0.706</td>
<td colspan="2">1.09</td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2">-2.77</td>
<td colspan="2">1.83E-13</td>
<td>5.713</td>
</tr>
<tr class="odd">
<td>PM-10</td>
<td></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td></td>
</tr>
<tr class="even">
<td>(NM)VOC</td>
<td>2.97</td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td></td>
</tr>
<tr class="odd">
<td>SOx</td>
<td></td>
<td colspan="2">1.56</td>
<td colspan="2">1.18E-3</td>
<td colspan="2">1.18E-14</td>
<td colspan="2"></td>
<td colspan="2"></td>
<td>1.041</td>
</tr>
<tr class="even">
<td>1,3-Butadiene</td>
<td>4.86</td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td></td>
</tr>
<tr class="odd">
<td>Formaldehyde</td>
<td>2.06</td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td></td>
</tr>
<tr class="even">
<td>Toluene</td>
<td>2.17</td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td></td>
</tr>
<tr class="odd">
<td>Benzene</td>
<td>1.54</td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td></td>
</tr>
<tr class="even">
<td>Acetaldehyde</td>
<td>2.59</td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td></td>
</tr>
<tr class="odd">
<td>Methane</td>
<td>0.034</td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td></td>
</tr>
<tr class="even">
<td>MTBE</td>
<td>1.40</td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td></td>
</tr>
<tr class="odd">
<td>DPM-10</td>
<td></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td></td>
</tr>
</tbody>
</table>

  ------------------------ ------------------------- ------------------- ------------------------- ------------------- ------------------------- ------------------- ------------------------- ------------------
  **Table 4. Normalized                                                                                                                                                                        
  Values of *b*~Xlijk~                                                                                                                                                                         
  Used in Evaluation of                                                                                                                                                                        
  Human Health and                                                                                                                                                                             
  Ecological Potential                                                                                                                                                                         
  Damage, u~HD~(HD) and                                                                                                                                                                        
  u~ED~(ED)**                                                                                                                                                                                  

  [Stressor]{.underline}   **[Human Health Damage                                                                                                                    **[Ecological Damage      
                           Category]{.underline}**                                                                                                                   Category]{.underline}**   

                           GLOBAL WARMING                                HUMAN TOXICITY                                OXIDANT FORMATION                             SPECIES LOSS              

                           [EPS-CDALY]{.underline}   [Eco-In.            [EPS-CDALY]{.underline}   [Eco-In.            [EPS-CDALY]{.underline}   [Eco-In.            [EPS-NEX]{.underline}     [Eco-In.
                                                     DALY]{.underline}                             DALY]{.underline}                             DALY]{.underline}                             PDF]{.underline}

  CO~2~                    (.38, .55, .78)           (.31, .45, .67)                                                                                                 (1, 1, 1)                 (0, 0, 0)

  CO                       (1, 1, 1)                 (0, 0, 0)           (.38, .55, .78)           (.31, .45, .67)                                                   (1, 1, 1)                 (0, 0, 0)

  NO~x~                    (1, 1, 1)                 (0, 0, 0)           (.40, .58, .90)           (.27, .42, .60)     (1, 1, 1)                 (0, 0, 0)           (.43, .64, 1.0)           (.21, .36, .56)

  PM-10                    (1, 1, 1)                 (0, 0, 0)           (.40, .58, .90)           (.27, .42, .60)                                                   (1, 1, 1)                 (0, 0, 0)

  (NM)VOC                  (1, 1, 1)                 (0, 0, 0)                                                         (.33, .50, .75)           (.33, .50, .75)     (1, 1, 1)                 (0, 0, 0)

  SO~x~                    (1, 1, 1)                 (0, 0, 0)           (.40, .58, .90)           (.27, .42, .60)                                                   (.43, .64, 1.0)           (.21, .36, .56)

  1,3-Butadiene            (1, 1, 1)                 (0, 0, 0)           (.21, .36, .56)           (.43, .64, 1.0)     (.21, .36, .56)           (.43, .64, 1.0)     (1, 1, 1)                 (0, 0, 0)

  Formaldehyde             (1, 1, 1)                 (0, 0, 0)           (.21, .36, .56)           (.43, .64, 1.0)     (.21, .36, .56)           (.43, .64, 1.0)     (1, 1, 1)                 (0, 0, 0)

  Toluene                  (1, 1, 1)                 (0, 0, 0)                                                         (.21, .36, .56)           (.43, .64, 1.0)     (.40, .58, .90)           (.27, .42, .60)

  Benzene                  (1, 1, 1)                 (0, 0, 0)           (.31, .45, .67)           (.38, ,55, .78)     (.31, .45, .67)           (.38, ,55, .78)     (.40, .58, .90)           (.27, .42, .60)

  Acetaldehyde             (1, 1, 1)                 (0, 0, 0)           (0, 0, 0)                 (1, 1, 1)           (.31, .45, .67)           (.38, ,55, .78)     (1, 1, 1)                 (0, 0, 0)

  CH4                      (.38, .55, .78)           (.31, .45, .67)                                                   (.40, .58, .90)           (.27, .42, .60)     (1, 1, 1)                 (0, 0, 0)

  MTBE                     (1, 1, 1)                 (0, 0, 0)                                                         (.21, .36, .56)           (.43, .64, 1.0)     (1, 1, 1)                 (0, 0, 0)

  DPM-10                   (1, 1, 1)                 (0, 0, 0)           (.43, .64, 1.0)           (.21, .36, .56)     (0, 0, 0)                 (1, 1, 1)           (.45, .67, 1.17)          (.09, .33, .67)
  ------------------------ ------------------------- ------------------- ------------------------- ------------------- ------------------------- ------------------- ------------------------- ------------------

  ------------------- --------------------- ------------------- --------------------- --------------------
  **Table 5. Unit                                                                     
  Partial Utility                                                                     
  Factors Used in                                                                     
  Simulation**                                                                        

  [Veh.               [Utility              [Per                [Per Minute Engine    [Per Engine
  Type]{.underline}   Factor]{.underline}   Mile]{.underline}   Idling]{.underline}   Start]{.underline}

  1                   u~HD~(HD)             -(2.665E-6,         -(4.405E-7, 6.393E-7, -(4.210E-7,
                                            3.970E-6, 5.800E-6) 9.230E-7)             6.258E-7, 9.053E-7)

                      u~ED~(ED)             -(3.833E-6,         -(7.463E-7, 8.228E-7, -(7.168E-7,
                                            4.300E-6, 4.918E-6) 9.245E-7)             8.763E-7, 1.090E-6)

                      u~HP~(HP)             -(1.523E-6,         -(6.258E-7, 1.795E-6, -(4.015E-7,
                                            4.370E-6, 1.476E-5) 8.753E-6)             1.152E-6, 5.063E-6)

                      u~EP~(EP)             -(1.767E-6,         -(3.853E-7, 1.242E-6, -(2.575E-7,
                                            5.693E-6, 1.774E-5) 5.993E-6)             8.295E-7, 4.330E-6)

                      u~R~(R)               -8.320E-06          -8.955E-07            -6.133E-07

                      u~O~(O)               -8.630E-06          -9.105E-08            -6.250E-08

  2                   u~HD~(HD)             -(3.243E-6,         -(1.822E-7, 2.753E-7, -(1.235E-7,
                                            4.833E-6, 7.050E-6) 3.995E-7)             1.865E-7, 2.708E-7)

                      u~ED~(ED)             -(5.210E-6,         -(2.461E-7, 3.023E-7, -(1.686E-7,
                                            5.913E-6, 6.843E-6) 3.775E-7)             2.070E-7, 2.583E-7)

                      u~HP~(HP)             -(1.899E-6,         -(8.180E-8, 2.347E-7, -(5.613E-8,
                                            5.448E-6, 1.784E-5) 6.928E-7)             1.610E-7, 4.750E-7)

                      u~EP~(EP)             -(2.239E-6,         -(9.038E-8, 2.913E-7, -(6.215E-8,
                                            7.215E-6, 2.230E-5) 1.042E-6)             2.002E-7, 7.140E-7)

                      u~R~(R)               -8.215E-06          -6.783E-08            -4.710E-08

                      u~O~(O)               -9.155E-06          -7.143E-09            -3.573E-09

  3                   u~HD~(HD)             -(4.038E-6,         -(7.898E-7, 1.143E-6, -(9.730E-7,
                                            6.018E-6, 8.778E-6) 1.649E-6)             1.460E-6, 2.100E-6)

                      u~ED~(ED)             -(5.960E-6,         -(1.343E-6, 1.473E-6, -(1.695E-6,
                                            6.880E-6, 8.038E-6) 1.647E-6)             2.232E-6, 2.95E-6)

                      u~HP~(HP)             -(2.421E-6,         -(1.260E-6, 3.615E-6, -(9.505E-7,
                                            6.948E-6, 2.389E-5) 1.736E-5)             2.728E-6, 1.296E-5)

                      u~EP~(EP)             -(2.665E-6,         -(7.933E-7, 2.558E-6, -(3.758E-7,
                                            8.590E-6, 2.808E-5) 1.222E-5)             1.211E-6, 1.062E-5)

                      u~R~(R)               -1.164E-05          -1.601E-06            -7.168E-07

                      u~O~(O)               -8.273E-06          -2.788E-07            -7.323E-08

  4                   u~HD~(HD)             -(2.179E-5,         -(7.058E-6, 1.035E-5, -(4.910E-6,
                                            3.218E-5, 4.915E-5) 1.600E-5)             7.188E-6, 1.105E-5)

                      u~ED~(ED)             -(6.688E-6,         -(5.578E-7, 6.973E-7, -(5.768E-7,
                                            8.505E-6, 1.093E-5) 8.885E-7)             6.730E-7, 8.015E-7)

                      u~HP~(HP)             -(1.293E-5,         -(4.368E-6, 1.253E-5, -(3.768E-6,
                                            3.710E-5, 8.068E-5) 2.583E-5)             1.081E-5, 3.230E-5)

                      u~EP~(EP)             -(6.210E-6,         -(1.845E-6, 5.943E-6, -(1.344E-6,
                                            2.001E-5, 7.015E-5) 1.871E-5)             4.333E-6, 1.949E-5)

                      u~R~(R)               -7.630E-06          -1.053E-06            -7.153E-07

                      u~O~(O)               -8.953E-06          -9.825E-08            -6.608E-08
  ------------------- --------------------- ------------------- --------------------- --------------------

<table>
<colgroup>
<col style="width: 11%" />
<col style="width: 9%" />
<col style="width: 10%" />
<col style="width: 10%" />
<col style="width: 12%" />
<col style="width: 7%" />
<col style="width: 10%" />
<col style="width: 8%" />
<col style="width: 12%" />
<col style="width: 7%" />
</colgroup>
<tbody>
<tr class="odd">
<td colspan="10"><p
id="table-6.-values-of-selected-simulation-and-experimental-parameters"
class="heading">Table 6. Values of Selected Simulation and Experimental
Parameters</p></td>
</tr>
<tr class="even">
<td colspan="10"><p id="simulation-parameters"
class="heading">SIMULATION PARAMETERS</p></td>
</tr>
<tr class="odd">
<td colspan="10"><p><u>Request-Related Parameters:</u> <u>Value</u></p>
<p>Trip distance (miles) Exp (9.4)</p>
<p>Requested pick-up time Normal (13:00, 5:00)</p>
<p>Call-in time offset (hrs.) Exp (2.4)</p>
<p>Wheelchair patron loading/unloading time (hours) Uniform (0.1,
0.25)</p>
<p>Non-wheelchair patron loading/unloading time (hours) Uniform (0.0075,
0.01</p>
<p>Probability (p) of wheelchair request 0.2</p></td>
</tr>
<tr class="even">
<td colspan="10"><p><u>Schedule and Penalty Parameters:</u>
<u>Value</u></p>
<p>Early pick-up window (all requests, min.) 5</p>
<p>Late pick-up window—advance requests (min.) 15</p>
<p>Late pick-up window—immediate service requests (min.) 60</p>
<p>Lateness after which VERY LATE penalty applies (min.) 60</p>
<p>Earliness penalty ($/min.) 0.1</p>
<p>Lateness penalty ($/min.) 0.5</p>
<p>Flat-rate very late penalty ($) 100</p>
<p>Planned ride time factor 1.5</p>
<p>Maximum ride time factor 2.5</p></td>
</tr>
<tr class="odd">
<td colspan="10"><u>Vehicle Cost and Capacity Parameters:</u></td>
</tr>
<tr class="even">
<td colspan="10"><p><u>Vehicle Type</u> <u>Sym.</u> <u>$/mile</u>
<u>WhChr. Cap.</u> <u>Non-WhChr. Cap.</u></p>
<p>Gasoline “minivan” GV 0.375 1 3</p>
<p>CNG “minivan” CV 0.449 1 3</p>
<p>Gasoline “shuttle bus” GB 0.445 2 5</p>
<p>Diesel “shuttle bus” DB 0.413 2 5</p></td>
</tr>
<tr class="odd">
<td colspan="10"><u>Shift Schedules:</u></td>
</tr>
<tr class="even">
<td colspan="10"><p><u>Shift</u> <u>Start</u> <u>End</u> <u>Shift</u>
<u>Start</u> <u>End</u></p>
<p>1 00:00 08:00 4 12:00 20:00</p>
<p>2 04:00 12:00 5 16:00 24:00</p>
<p>3 08:00 16:00 6 20:00 04:00</p></td>
</tr>
<tr class="odd">
<td colspan="10"><p id="experimental-parameters"
class="heading">EXPERIMENTAL PARAMETERS</p></td>
</tr>
<tr class="even">
<td colspan="10"><p><u>Vehicle Shift Assignments:</u></p>
<p><u>Case</u> <u>Tot. Veh. Sim.</u> <u>Sh1</u> <u>Sh2</u> <u>Sh3</u>
<u>Sh4</u> <u>Sh5</u> <u>Sh6</u></p>
<p>A 150 11 28 40 39 22 10</p>
<p>B 180 13 34 48 47 26 12</p>
<p>C 210 15 40 55 55 30 15</p></td>
</tr>
<tr class="odd">
<td colspan="10"><p><u>Fleet Composition:</u></p>
<p><u>Case</u> <u>GV</u> <u>CV</u> <u>GB</u> <u>DB</u> <u>Case</u>
<u>GV</u> <u>CV</u> <u>GB</u> <u>DB</u></p>
<p>IA 39 39 36 36 IC 55 55 55 55</p>
<p>IB 47 47 43 43</p>
<p>IIA 75 75 IIC 105 105</p>
<p>IIB 90 90</p>
<p>IIIA 150 IIIC 210</p>
<p>IIIB 180</p></td>
</tr>
<tr class="even">
<td colspan="10"><p><u>Objective Function Environmental Weight
(w<sub>ENV</sub>):</u></p>
<p>Values: 0, 0.125, 0.25, 0.50, 0.75</p></td>
</tr>
<tr class="odd">
<td colspan="9"><p
id="table-7.-comparison-of-service-performance-results-for-simulated-cases"
class="heading">Table 7. Comparison of Service Performance Results for
Simulated Cases</p></td>
<td></td>
</tr>
<tr class="even">
<td><p><u>Fleet Size</u></p>
<p><u>(Tot. Veh.)</u></p></td>
<td><u>W<sub>env</sub></u></td>
<td><h1 id="requests">Requests</h1>
<p><u>Served</u></p></td>
<td><u>Rideshare</u></td>
<td><p><u>Mean P/U</u></p>
<p><u>Delay (min.)</u></p></td>
<td><u>Std. Dev.</u></td>
<td><p><u>Overall</u></p>
<p><u>O/T Perf.</u></p></td>
<td><u>Std. Dev.</u></td>
<td><p><u>Vehicle</u></p>
<p><u>Utilization</u></p></td>
<td></td>
</tr>
<tr class="odd">
<td colspan="9">Case I – Heterogeneous Fleet (CV, GV, GB, DB) (n = 10,
1000 requests/day)</td>
<td></td>
</tr>
<tr class="even">
<td rowspan="5">210</td>
<td><strong>0</strong></td>
<td><strong>9998</strong></td>
<td><strong>1.36</strong></td>
<td><strong>31.12</strong></td>
<td><strong>1.19</strong></td>
<td><strong>0.763</strong></td>
<td><strong>0.01</strong></td>
<td><strong>0.682</strong></td>
<td></td>
</tr>
<tr class="odd">
<td>.125</td>
<td>10000</td>
<td>1.37</td>
<td>32.73</td>
<td>1.12</td>
<td>0.748</td>
<td>0.01</td>
<td>0.674</td>
<td></td>
</tr>
<tr class="even">
<td>.25</td>
<td>9998</td>
<td>1.37</td>
<td>34.01</td>
<td>1.94</td>
<td>0.733</td>
<td>0.02</td>
<td>0.664</td>
<td></td>
</tr>
<tr class="odd">
<td>.5</td>
<td>9999</td>
<td>1.37</td>
<td>40.38</td>
<td>1.97</td>
<td>0.688</td>
<td>0.02</td>
<td>0.660</td>
<td></td>
</tr>
<tr class="even">
<td>.75</td>
<td>10000</td>
<td>1.34</td>
<td>49.00</td>
<td>2.74</td>
<td>0.649</td>
<td>0.01</td>
<td>0.667</td>
<td></td>
</tr>
<tr class="odd">
<td rowspan="5">180</td>
<td><strong>0</strong></td>
<td><strong>9968</strong></td>
<td><strong>1.37</strong></td>
<td><strong>32.47</strong></td>
<td><strong>1.49</strong></td>
<td><strong>0.754</strong></td>
<td><strong>0.02</strong></td>
<td><strong>0.782</strong></td>
<td></td>
</tr>
<tr class="even">
<td>.125</td>
<td>9976</td>
<td>1.38</td>
<td>33.48</td>
<td>1.16</td>
<td>0.742</td>
<td>0.01</td>
<td>0.777</td>
<td></td>
</tr>
<tr class="odd">
<td>.25</td>
<td>9974</td>
<td>1.38</td>
<td>35.98</td>
<td>1.43</td>
<td>0.715</td>
<td>0.02</td>
<td>0.769</td>
<td></td>
</tr>
<tr class="even">
<td>.5</td>
<td>9979</td>
<td>1.37</td>
<td>43.51</td>
<td>2.43</td>
<td>0.672</td>
<td>0.02</td>
<td>0.758</td>
<td></td>
</tr>
<tr class="odd">
<td>.75</td>
<td>9955</td>
<td>1.35</td>
<td>52.54</td>
<td>2.71</td>
<td>0.625</td>
<td>0.02</td>
<td>0.772</td>
<td></td>
</tr>
<tr class="even">
<td rowspan="5">150</td>
<td><strong>0</strong></td>
<td><strong>9727</strong></td>
<td><strong>1.38</strong></td>
<td><strong>42.84</strong></td>
<td><strong>2.80</strong></td>
<td><strong>0.686</strong></td>
<td><strong>0.02</strong></td>
<td><strong>0.877</strong></td>
<td></td>
</tr>
<tr class="odd">
<td>.125</td>
<td>9717</td>
<td>1.39</td>
<td>43.04</td>
<td>2.32</td>
<td>0.680</td>
<td>0.01</td>
<td>0.873</td>
<td></td>
</tr>
<tr class="even">
<td>.25</td>
<td>9731</td>
<td>1.39</td>
<td>43.33</td>
<td>1.73</td>
<td>0.677</td>
<td>0.01</td>
<td>0.867</td>
<td></td>
</tr>
<tr class="odd">
<td>.5</td>
<td>9650</td>
<td>1.38</td>
<td>51.79</td>
<td>2.29</td>
<td>0.624</td>
<td>0.02</td>
<td>0.870</td>
<td></td>
</tr>
<tr class="even">
<td>.75</td>
<td>9474</td>
<td>1.34</td>
<td>61.27</td>
<td>2.71</td>
<td>0.594</td>
<td>0.01</td>
<td>0.869</td>
<td></td>
</tr>
<tr class="odd">
<td colspan="9">Case II – Heterogeneous Fleet (CV, GB) (n = 10, 1000
requests/day)</td>
<td></td>
</tr>
<tr class="even">
<td rowspan="5">210</td>
<td><strong>0</strong></td>
<td><strong>9998</strong></td>
<td><strong>1.36</strong></td>
<td><strong>30.88</strong></td>
<td><strong>1.06</strong></td>
<td><strong>0.771</strong></td>
<td><strong>0.02</strong></td>
<td><strong>0.687</strong></td>
<td></td>
</tr>
<tr class="odd">
<td>.125</td>
<td>9999</td>
<td>1.35</td>
<td>31.60</td>
<td>0.77</td>
<td>0.761</td>
<td>0.01</td>
<td>0.686</td>
<td></td>
</tr>
<tr class="even">
<td>.25</td>
<td>9999</td>
<td>1.35</td>
<td>32.88</td>
<td>1.10</td>
<td>0.747</td>
<td>0.01</td>
<td>0.682</td>
<td></td>
</tr>
<tr class="odd">
<td>.5</td>
<td>9998</td>
<td>1.36</td>
<td>36.70</td>
<td>1.53</td>
<td>0.712</td>
<td>0.02</td>
<td>0.668</td>
<td></td>
</tr>
<tr class="even">
<td>.75</td>
<td>9999</td>
<td>1.34</td>
<td>46.60</td>
<td>1.97</td>
<td>0.657</td>
<td>0.01</td>
<td>0.677</td>
<td></td>
</tr>
<tr class="odd">
<td rowspan="5">180</td>
<td><strong>0</strong></td>
<td><strong>9972</strong></td>
<td><strong>1.37</strong></td>
<td><strong>32.60</strong></td>
<td><strong>2.05</strong></td>
<td><strong>0.757</strong></td>
<td><strong>0.01</strong></td>
<td><strong>0.785</strong></td>
<td></td>
</tr>
<tr class="even">
<td>.125</td>
<td>9968</td>
<td>1.35</td>
<td>33.28</td>
<td>1.25</td>
<td>0.746</td>
<td>0.01</td>
<td>0.785</td>
<td></td>
</tr>
<tr class="odd">
<td>.25</td>
<td>9976</td>
<td>1.37</td>
<td>34.34</td>
<td>1.31</td>
<td>0.735</td>
<td>0.02</td>
<td>0.783</td>
<td></td>
</tr>
<tr class="even">
<td>.5</td>
<td>9970</td>
<td>1.36</td>
<td>38.21</td>
<td>1.70</td>
<td>0.704</td>
<td>0.01</td>
<td>0.774</td>
<td></td>
</tr>
<tr class="odd">
<td>.75</td>
<td>9957</td>
<td>1.35</td>
<td>48.09</td>
<td>2.17</td>
<td>0.655</td>
<td>0.01</td>
<td>0.780</td>
<td></td>
</tr>
<tr class="even">
<td rowspan="5">150</td>
<td><strong>0</strong></td>
<td><strong>9699</strong></td>
<td><strong>1.37</strong></td>
<td><strong>41.90</strong></td>
<td><strong>3.03</strong></td>
<td><strong>0.696</strong></td>
<td><strong>0.02</strong></td>
<td><strong>0.877</strong></td>
<td></td>
</tr>
<tr class="odd">
<td>.125</td>
<td>9718</td>
<td>1.38</td>
<td>42.83</td>
<td>2.28</td>
<td>0.685</td>
<td>0.02</td>
<td>0.876</td>
<td></td>
</tr>
<tr class="even">
<td>.25</td>
<td>9703</td>
<td>1.37</td>
<td>43.49</td>
<td>1.81</td>
<td>0.679</td>
<td>0.01</td>
<td>0.876</td>
<td></td>
</tr>
<tr class="odd">
<td>.5</td>
<td>9660</td>
<td>1.37</td>
<td>46.69</td>
<td>2.28</td>
<td>0.655</td>
<td>0.01</td>
<td>0.869</td>
<td></td>
</tr>
<tr class="even">
<td>.75</td>
<td>9446</td>
<td>1.34</td>
<td>56.58</td>
<td>1.54</td>
<td>0.613</td>
<td>0.01</td>
<td>0.874</td>
<td></td>
</tr>
<tr class="odd">
<td colspan="9">Case III – Homogeneous Fleet (GB) (n = 10, 1000
requests/day)</td>
<td></td>
</tr>
<tr class="even">
<td rowspan="5">210</td>
<td><strong>0</strong></td>
<td><strong>9996</strong></td>
<td><strong>1.36</strong></td>
<td><strong>30.81</strong></td>
<td><strong>1.26</strong></td>
<td><strong>0.773</strong></td>
<td><strong>0.01</strong></td>
<td><strong>0.688</strong></td>
<td></td>
</tr>
<tr class="odd">
<td>.125</td>
<td>9999</td>
<td>1.36</td>
<td>31.71</td>
<td>0.69</td>
<td>0.761</td>
<td>0.01</td>
<td>0.684</td>
<td></td>
</tr>
<tr class="even">
<td>.25</td>
<td>9999</td>
<td>1.37</td>
<td>32.56</td>
<td>1.03</td>
<td>0.749</td>
<td>0.02</td>
<td>0.683</td>
<td></td>
</tr>
<tr class="odd">
<td>.5</td>
<td>9997</td>
<td>1.36</td>
<td>35.93</td>
<td>1.13</td>
<td>0.729</td>
<td>0.01</td>
<td>0.675</td>
<td></td>
</tr>
<tr class="even">
<td>.75</td>
<td>9997</td>
<td>1.35</td>
<td>44.08</td>
<td>1.63</td>
<td>0.675</td>
<td>0.02</td>
<td>0.689</td>
<td></td>
</tr>
<tr class="odd">
<td rowspan="5">180</td>
<td><strong>0</strong></td>
<td><strong>9970</strong></td>
<td><strong>1.37</strong></td>
<td><strong>32.40</strong></td>
<td><strong>1.42</strong></td>
<td><strong>0.757</strong></td>
<td><strong>0.02</strong></td>
<td><strong>0.784</strong></td>
<td></td>
</tr>
<tr class="even">
<td>.125</td>
<td>9966</td>
<td>1.37</td>
<td>33.55</td>
<td>0.95</td>
<td>0.744</td>
<td>0.01</td>
<td>0.780</td>
<td></td>
</tr>
<tr class="odd">
<td>.25</td>
<td>9978</td>
<td>1.37</td>
<td>34.23</td>
<td>0.96</td>
<td>0.739</td>
<td>0.01</td>
<td>0.779</td>
<td></td>
</tr>
<tr class="even">
<td>.5</td>
<td>9970</td>
<td>1.36</td>
<td>37.52</td>
<td>1.66</td>
<td>0.717</td>
<td>0.01</td>
<td>0.777</td>
<td></td>
</tr>
<tr class="odd">
<td>.75</td>
<td>9943</td>
<td>1.35</td>
<td>45.87</td>
<td>2.09</td>
<td>0.670</td>
<td>0.02</td>
<td>0.792</td>
<td></td>
</tr>
<tr class="even">
<td rowspan="5">150</td>
<td><strong>0</strong></td>
<td><strong>9733</strong></td>
<td><strong>1.40</strong></td>
<td><strong>42.26</strong></td>
<td><strong>2.80</strong></td>
<td><strong>0.694</strong></td>
<td><strong>0.02</strong></td>
<td><strong>0.877</strong></td>
<td></td>
</tr>
<tr class="odd">
<td>.125</td>
<td>9738</td>
<td>1.39</td>
<td>42.64</td>
<td>2.39</td>
<td>0.684</td>
<td>0.03</td>
<td>0.877</td>
<td></td>
</tr>
<tr class="even">
<td>.25</td>
<td>9728</td>
<td>1.40</td>
<td>43.43</td>
<td>2.42</td>
<td>0.681</td>
<td>0.02</td>
<td>0.876</td>
<td></td>
</tr>
<tr class="odd">
<td>.5</td>
<td>9678</td>
<td>1.38</td>
<td>46.74</td>
<td>2.12</td>
<td>0.658</td>
<td>0.02</td>
<td>0.872</td>
<td></td>
</tr>
<tr class="even">
<td>.75</td>
<td>9424</td>
<td>1.33</td>
<td>56.64</td>
<td>1.52</td>
<td>0.615</td>
<td>0.01</td>
<td>0.879</td>
<td></td>
</tr>
<tr class="odd">
<td colspan="9"><p>1) “Baseline case” results (without environmental
scheduling algorithm) shown in boldface.</p>
<p>2) Ridesharing is calculated as the total number of requests served
divided by the number of trip starts.</p>
<p>3) Mean pick-up delay calculated as actual time service began minus
requested pick-up time. "Negative" delays<br />
(vehicle arrives early) are assigned a delay value of zero.</p>
<p>4) Overall on-time performance = fraction of pick-ups where vehicle
arrived early or within the "on time" window.<br />
5) Vehicle utilization = the total number of hours vehicles were in
transit (with or without passengers on-board) plus<br />
total loading/unloading times divided by the total number of available
vehicle hours.</p></td>
<td></td>
</tr>
</tbody>
</table>

<table>
<colgroup>
<col style="width: 12%" />
<col style="width: 7%" />
<col style="width: 11%" />
<col style="width: 11%" />
<col style="width: 9%" />
<col style="width: 10%" />
<col style="width: 9%" />
<col style="width: 10%" />
<col style="width: 8%" />
<col style="width: 11%" />
</colgroup>
<tbody>
<tr class="odd">
<td colspan="10"><strong>Table 8. Scheduling Algorithm Results—Cost and
Environmental Performance</strong></td>
</tr>
<tr class="even">
<td><p><u>Fleet Size</u></p>
<p><u>(Tot. Veh.)</u></p></td>
<td><u>W<sub>env</sub></u></td>
<td><p><u>Average</u></p>
<p><u>Distance</u></p></td>
<td><p><u>Avg. Itin.</u></p>
<p><u>Cost ($)</u></p></td>
<td><p><u>Std.</u></p>
<p><u>Dev.</u></p></td>
<td><u>u(Cost)</u></td>
<td><p><u>Std.</u></p>
<p><u>Dev.</u></p></td>
<td><u>u(Env.)</u></td>
<td><p><u>Std.</u></p>
<p><u>Dev.</u></p></td>
<td><u>u(System)</u></td>
</tr>
<tr class="odd">
<td colspan="10">Case I – Heterogeneous Fleet (CV, GV, GB, DB) (n = 10,
1000 requests/day)</td>
</tr>
<tr class="even">
<td rowspan="5">210</td>
<td><strong>0</strong></td>
<td><strong>29626.2</strong></td>
<td><strong>15157.72</strong></td>
<td><strong>416.28</strong></td>
<td><strong>-0.2010</strong></td>
<td><strong>0.0056</strong></td>
<td><strong>-0.4671</strong></td>
<td><strong>0.0075</strong></td>
<td><strong>-0.2010</strong></td>
</tr>
<tr class="odd">
<td>.125</td>
<td>29252.0</td>
<td>15796.81</td>
<td>447.54</td>
<td>-0.2096</td>
<td>0.0060</td>
<td>-0.3159</td>
<td>0.0168</td>
<td>-0.2228</td>
</tr>
<tr class="even">
<td>.25</td>
<td>28774.0</td>
<td>16617.17</td>
<td>631.21</td>
<td>-0.2204</td>
<td>0.0085</td>
<td>-0.2965</td>
<td>0.0082</td>
<td>-0.2394</td>
</tr>
<tr class="odd">
<td>.5</td>
<td>28549.6</td>
<td>20084.79</td>
<td>983.20</td>
<td>-0.2666</td>
<td>0.0131</td>
<td>-0.2827</td>
<td>0.0102</td>
<td>-0.2747</td>
</tr>
<tr class="even">
<td>.75</td>
<td>28910.0</td>
<td>25556.68</td>
<td>1519.62</td>
<td>-0.3395</td>
<td>0.0203</td>
<td>-0.2884</td>
<td>0.0090</td>
<td>-0.3011</td>
</tr>
<tr class="odd">
<td rowspan="5">180</td>
<td><strong>0</strong></td>
<td><strong>29061.3</strong></td>
<td><strong>15659.72</strong></td>
<td><strong>690.72</strong></td>
<td><strong>-0.2078</strong></td>
<td><strong>0.0092</strong></td>
<td><strong>-0.4378</strong></td>
<td><strong>0.0053</strong></td>
<td><strong>-0.2078</strong></td>
</tr>
<tr class="even">
<td>.125</td>
<td>28878.8</td>
<td>16180.12</td>
<td>602.38</td>
<td>-0.2147</td>
<td>0.0081</td>
<td>-0.3622</td>
<td>0.0126</td>
<td>-0.2331</td>
</tr>
<tr class="odd">
<td>.25</td>
<td>28523.4</td>
<td>17245.32</td>
<td>872.21</td>
<td>-0.2289</td>
<td>0.0117</td>
<td>-0.3462</td>
<td>0.0131</td>
<td>-0.2582</td>
</tr>
<tr class="even">
<td>.5</td>
<td>28095.2</td>
<td>21721.36</td>
<td>1214.64</td>
<td>-0.2884</td>
<td>0.0163</td>
<td>-0.3232</td>
<td>0.0093</td>
<td>-0.3058</td>
</tr>
<tr class="odd">
<td>.75</td>
<td>28657.7</td>
<td>27425.69</td>
<td>1319.89</td>
<td>-0.3644</td>
<td>0.0176</td>
<td>-0.3374</td>
<td>0.0104</td>
<td>-0.3441</td>
</tr>
<tr class="even">
<td rowspan="5">150</td>
<td><strong>0</strong></td>
<td><strong>27080.4</strong></td>
<td><strong>20418.81</strong></td>
<td><strong>1434.68</strong></td>
<td><strong>-0.2715</strong></td>
<td><strong>0.0191</strong></td>
<td><strong>-0.3980</strong></td>
<td><strong>0.0064</strong></td>
<td><strong>-0.2715</strong></td>
</tr>
<tr class="odd">
<td>.125</td>
<td>26960.9</td>
<td>20332.97</td>
<td>897.77</td>
<td>-0.2703</td>
<td>0.0120</td>
<td>-0.3665</td>
<td>0.0044</td>
<td>-0.2823</td>
</tr>
<tr class="even">
<td>.25</td>
<td>26753.6</td>
<td>20582.79</td>
<td>829.29</td>
<td>-0.2736</td>
<td>0.0111</td>
<td>-0.3589</td>
<td>0.0070</td>
<td>-0.2949</td>
</tr>
<tr class="odd">
<td>.5</td>
<td>26867.0</td>
<td>24983.19</td>
<td>1271.53</td>
<td>-0.3321</td>
<td>0.0170</td>
<td>-0.3559</td>
<td>0.0090</td>
<td>-0.3440</td>
</tr>
<tr class="even">
<td>.75</td>
<td>26913.9</td>
<td>29922.99</td>
<td>1269.21</td>
<td>-0.3981</td>
<td>0.0170</td>
<td>-0.3541</td>
<td>0.0072</td>
<td>-0.3651</td>
</tr>
<tr class="odd">
<td colspan="10">Case II – Heterogeneous Fleet (CV, GB) (n = 10, 1000
requests/day)</td>
</tr>
<tr class="even">
<td rowspan="5">210</td>
<td><strong>0</strong></td>
<td><strong>29838.3</strong></td>
<td><strong>16225.27</strong></td>
<td><strong>520.43</strong></td>
<td><strong>-0.2153</strong></td>
<td><strong>0.0069</strong></td>
<td><strong>-0.2987</strong></td>
<td><strong>0.0056</strong></td>
<td><strong>-0.2153</strong></td>
</tr>
<tr class="odd">
<td>.125</td>
<td>29795.5</td>
<td>16566.07</td>
<td>437.63</td>
<td>-0.2197</td>
<td>0.0059</td>
<td>-0.2817</td>
<td>0.0068</td>
<td>-0.2274</td>
</tr>
<tr class="even">
<td>.25</td>
<td>29614.4</td>
<td>17196.09</td>
<td>412.02</td>
<td>-0.2281</td>
<td>0.0054</td>
<td>-0.2793</td>
<td>0.0079</td>
<td>-0.2409</td>
</tr>
<tr class="odd">
<td>.5</td>
<td>28959.7</td>
<td>19302.05</td>
<td>753.74</td>
<td>-0.2562</td>
<td>0.0101</td>
<td>-0.2716</td>
<td>0.0054</td>
<td>-0.2639</td>
</tr>
<tr class="even">
<td>.75</td>
<td>29386.7</td>
<td>25481.85</td>
<td>1149.79</td>
<td>-0.3386</td>
<td>0.0154</td>
<td>-0.2752</td>
<td>0.0066</td>
<td>-0.2911</td>
</tr>
<tr class="odd">
<td rowspan="5">180</td>
<td><strong>0</strong></td>
<td><strong>29188.7</strong></td>
<td><strong>16819.80</strong></td>
<td><strong>757.82</strong></td>
<td><strong>-0.2232</strong></td>
<td><strong>0.0102</strong></td>
<td><strong>-0.2880</strong></td>
<td><strong>0.0049</strong></td>
<td><strong>-0.2232</strong></td>
</tr>
<tr class="even">
<td>.125</td>
<td>29190.3</td>
<td>17230.37</td>
<td>676.94</td>
<td>-0.2286</td>
<td>0.0091</td>
<td>-0.2800</td>
<td>0.0045</td>
<td>-0.2351</td>
</tr>
<tr class="odd">
<td>.25</td>
<td>29107.5</td>
<td>17731.01</td>
<td>618.03</td>
<td>-0.2352</td>
<td>0.0084</td>
<td>-0.2789</td>
<td>0.0050</td>
<td>-0.2461</td>
</tr>
<tr class="even">
<td>.5</td>
<td>28752.1</td>
<td>19981.29</td>
<td>895.22</td>
<td>-0.2652</td>
<td>0.0120</td>
<td>-0.2744</td>
<td>0.0039</td>
<td>-0.2698</td>
</tr>
<tr class="odd">
<td>.75</td>
<td>28999.0</td>
<td>25832.82</td>
<td>1113.36</td>
<td>-0.3434</td>
<td>0.0149</td>
<td>-0.2765</td>
<td>0.0060</td>
<td>-0.2932</td>
</tr>
<tr class="even">
<td rowspan="5">150</td>
<td><strong>0</strong></td>
<td><strong>27090.1</strong></td>
<td><strong>20698.34</strong></td>
<td><strong>1557.70</strong></td>
<td><strong>-0.2752</strong></td>
<td><strong>0.0208</strong></td>
<td><strong>-0.2643</strong></td>
<td><strong>0.0033</strong></td>
<td><strong>-0.2752</strong></td>
</tr>
<tr class="odd">
<td>.125</td>
<td>27061.6</td>
<td>21188.18</td>
<td>1348.96</td>
<td>-0.2817</td>
<td>0.0179</td>
<td>-0.2609</td>
<td>0.0025</td>
<td>-0.2791</td>
</tr>
<tr class="even">
<td>.25</td>
<td>27062.7</td>
<td>21532.41</td>
<td>896.29</td>
<td>-0.2862</td>
<td>0.0120</td>
<td>-0.2608</td>
<td>0.0036</td>
<td>-0.2798</td>
</tr>
<tr class="odd">
<td>.5</td>
<td>26852.6</td>
<td>23527.71</td>
<td>1128.79</td>
<td>-0.3128</td>
<td>0.0151</td>
<td>-0.2583</td>
<td>0.0029</td>
<td>-0.2855</td>
</tr>
<tr class="even">
<td>.75</td>
<td>27065.5</td>
<td>28846.22</td>
<td>866.60</td>
<td>-0.3838</td>
<td>0.0115</td>
<td>-0.2600</td>
<td>0.0030</td>
<td>-0.2910</td>
</tr>
<tr class="odd">
<td colspan="10">Case III – Homogeneous Fleet (GB) (n = 10, 1000
requests/day)</td>
</tr>
<tr class="even">
<td rowspan="5">210</td>
<td><strong>0</strong></td>
<td><strong>29904.2</strong></td>
<td><strong>16266.48</strong></td>
<td><strong>550.57</strong></td>
<td><strong>-0.2159</strong></td>
<td><strong>0.0074</strong></td>
<td><strong>-0.3228</strong></td>
<td><strong>0.0094</strong></td>
<td><strong>-0.2159</strong></td>
</tr>
<tr class="odd">
<td>.125</td>
<td>29695.1</td>
<td>16550.16</td>
<td>315.66</td>
<td>-0.2196</td>
<td>0.0043</td>
<td>-0.3204</td>
<td>0.0078</td>
<td>-0.2322</td>
</tr>
<tr class="even">
<td>.25</td>
<td>29668.5</td>
<td>17295.16</td>
<td>501.07</td>
<td>-0.2293</td>
<td>0.0068</td>
<td>-0.3201</td>
<td>0.0073</td>
<td>-0.2520</td>
</tr>
<tr class="odd">
<td>.5</td>
<td>29271.0</td>
<td>19432.14</td>
<td>731.37</td>
<td>-0.2578</td>
<td>0.0097</td>
<td>-0.3156</td>
<td>0.0081</td>
<td>-0.2867</td>
</tr>
<tr class="even">
<td>.75</td>
<td>29925.5</td>
<td>24983.88</td>
<td>831.03</td>
<td>-0.3318</td>
<td>0.0112</td>
<td>-0.3229</td>
<td>0.0078</td>
<td>-0.3251</td>
</tr>
<tr class="odd">
<td rowspan="5">180</td>
<td><strong>0</strong></td>
<td><strong>29142.9</strong></td>
<td><strong>16601.94</strong></td>
<td><strong>488.41</strong></td>
<td><strong>-0.2204</strong></td>
<td><strong>0.0066</strong></td>
<td><strong>-0.3141</strong></td>
<td><strong>0.0050</strong></td>
<td><strong>-0.2204</strong></td>
</tr>
<tr class="even">
<td>.125</td>
<td>28977.7</td>
<td>17080.74</td>
<td>628.31</td>
<td>-0.2266</td>
<td>0.0083</td>
<td>-0.3122</td>
<td>0.0047</td>
<td>-0.2373</td>
</tr>
<tr class="odd">
<td>.25</td>
<td>28954.6</td>
<td>17724.38</td>
<td>525.52</td>
<td>-0.2351</td>
<td>0.0071</td>
<td>-0.3120</td>
<td>0.0051</td>
<td>-0.2543</td>
</tr>
<tr class="even">
<td>.5</td>
<td>28869.7</td>
<td>19930.39</td>
<td>1009.47</td>
<td>-0.2645</td>
<td>0.0135</td>
<td>-0.3110</td>
<td>0.0038</td>
<td>-0.2878</td>
</tr>
<tr class="odd">
<td>.75</td>
<td>29462.5</td>
<td>25553.31</td>
<td>1118.42</td>
<td>-0.3395</td>
<td>0.0150</td>
<td>-0.3177</td>
<td>0.0054</td>
<td>-0.3231</td>
</tr>
<tr class="even">
<td rowspan="5">150</td>
<td><strong>0</strong></td>
<td><strong>27105.0</strong></td>
<td><strong>20976.28</strong></td>
<td><strong>1260.17</strong></td>
<td><strong>-0.2789</strong></td>
<td><strong>0.0168</strong></td>
<td><strong>-0.2911</strong></td>
<td><strong>0.0029</strong></td>
<td><strong>-0.2789</strong></td>
</tr>
<tr class="odd">
<td>.125</td>
<td>27096.7</td>
<td>21171.14</td>
<td>1181.05</td>
<td>-0.2815</td>
<td>0.0157</td>
<td>-0.2910</td>
<td>0.0031</td>
<td>-0.2827</td>
</tr>
<tr class="even">
<td>.25</td>
<td>27047.1</td>
<td>21702.76</td>
<td>989.87</td>
<td>-0.2884</td>
<td>0.0132</td>
<td>-0.2905</td>
<td>0.0034</td>
<td>-0.2889</td>
</tr>
<tr class="odd">
<td>.5</td>
<td>26952.3</td>
<td>23692.69</td>
<td>1101.36</td>
<td>-0.3150</td>
<td>0.0146</td>
<td>-0.2894</td>
<td>0.0040</td>
<td>-0.3022</td>
</tr>
<tr class="even">
<td>.75</td>
<td>27262.3</td>
<td>28909.33</td>
<td>1178.80</td>
<td>-0.3846</td>
<td>0.0157</td>
<td>-0.2928</td>
<td>0.0049</td>
<td>-0.3158</td>
</tr>
</tbody>
</table>

<table>
<colgroup>
<col style="width: 8%" />
<col style="width: 7%" />
<col style="width: 7%" />
<col style="width: 7%" />
<col style="width: 7%" />
<col style="width: 7%" />
<col style="width: 12%" />
<col style="width: 7%" />
<col style="width: 11%" />
<col style="width: 7%" />
<col style="width: 11%" />
<col style="width: 7%" />
</colgroup>
<tbody>
<tr class="odd">
<td colspan="12"><strong>Table 9. Comparison of Results Affecting
Environmental Performance</strong></td>
</tr>
<tr class="even">
<td rowspan="2"><p><u>Fleet</u></p>
<p><u>Size</u></p></td>
<td rowspan="2"><u>W<sub>env</sub></u></td>
<td colspan="4"><u>Avg. Vehicles Utilized</u></td>
<td rowspan="2"><p><u>Average</u></p>
<p><u>Distance</u></p></td>
<td rowspan="2"><p><u>Std.</u></p>
<p><u>Dev.</u></p></td>
<td rowspan="2"><p><u>Engine</u></p>
<p><u>Starts</u></p></td>
<td rowspan="2"><p><u>Std.</u></p>
<p><u>Dev.</u></p></td>
<td rowspan="2"><p><u>Waiting<sup>(1)</sup></u></p>
<p><u>Idle (hrs.)</u></p></td>
<td rowspan="2"><p><u>Std.</u></p>
<p><u>Dev.</u></p></td>
</tr>
<tr class="odd">
<td><u>GV</u></td>
<td><u>CV</u></td>
<td><u>GB</u></td>
<td><h1 id="db">DB</h1></td>
</tr>
<tr class="even">
<td colspan="12">Case I – Heterogeneous Fleet (CV, GV, GB, DB) (n = 10,
1000 requests/day)</td>
</tr>
<tr class="odd">
<td rowspan="5">210</td>
<td><strong>0</strong></td>
<td><strong>55.0</strong></td>
<td><strong>31.3</strong></td>
<td><strong>46.1</strong></td>
<td><strong>49.7</strong></td>
<td><strong>29626.2</strong></td>
<td><strong>602.5</strong></td>
<td><strong>420.4</strong></td>
<td><strong>19.6</strong></td>
<td><strong>2.15</strong></td>
<td><strong>0.56</strong></td>
</tr>
<tr class="even">
<td>.125</td>
<td>55.0</td>
<td>54.7</td>
<td>45.3</td>
<td>21.6</td>
<td>29252.0</td>
<td>494.5</td>
<td>406.0</td>
<td>14.9</td>
<td>2.09</td>
<td>0.41</td>
</tr>
<tr class="odd">
<td>.25</td>
<td>55.0</td>
<td>54.8</td>
<td>44.7</td>
<td>16.9</td>
<td>28774.0</td>
<td>345.1</td>
<td>398.7</td>
<td>7.9</td>
<td>2.61</td>
<td>0.72</td>
</tr>
<tr class="even">
<td>.5</td>
<td>55.0</td>
<td>54.5</td>
<td>42.9</td>
<td>13.7</td>
<td>28549.6</td>
<td>280.9</td>
<td>381.6</td>
<td>14.7</td>
<td>2.32</td>
<td>0.82</td>
</tr>
<tr class="odd">
<td>.75</td>
<td>55.0</td>
<td>54.3</td>
<td>42.8</td>
<td>14.5</td>
<td>28910.0</td>
<td>331.2</td>
<td>378.0</td>
<td>16.3</td>
<td>2.44</td>
<td>0.94</td>
</tr>
<tr class="even">
<td rowspan="5">180</td>
<td><strong>0</strong></td>
<td><strong>47.0</strong></td>
<td><strong>40.8</strong></td>
<td><strong>41.5</strong></td>
<td><strong>43.0</strong></td>
<td><strong>29061.3</strong></td>
<td><strong>416.3</strong></td>
<td><strong>397.7</strong></td>
<td><strong>10.8</strong></td>
<td><strong>2.14</strong></td>
<td><strong>0.82</strong></td>
</tr>
<tr class="odd">
<td>.125</td>
<td>47.0</td>
<td>47.0</td>
<td>41.5</td>
<td>33.7</td>
<td>28878.8</td>
<td>425.3</td>
<td>389.2</td>
<td>12.0</td>
<td>2.11</td>
<td>0.90</td>
</tr>
<tr class="even">
<td>.25</td>
<td>47.0</td>
<td>47.0</td>
<td>41.4</td>
<td>31.2</td>
<td>28523.4</td>
<td>431.0</td>
<td>384.8</td>
<td>9.0</td>
<td>2.32</td>
<td>0.75</td>
</tr>
<tr class="odd">
<td>.5</td>
<td>47.0</td>
<td>47.0</td>
<td>41.1</td>
<td>25.9</td>
<td>28095.2</td>
<td>374.1</td>
<td>372.9</td>
<td>12.1</td>
<td>1.94</td>
<td>0.40</td>
</tr>
<tr class="even">
<td>.75</td>
<td>47.0</td>
<td>47.0</td>
<td>40.2</td>
<td>28.1</td>
<td>28657.7</td>
<td>488.3</td>
<td>368.2</td>
<td>11.2</td>
<td>1.74</td>
<td>0.63</td>
</tr>
<tr class="odd">
<td rowspan="5">150</td>
<td><strong>0</strong></td>
<td><strong>39.0</strong></td>
<td><strong>37.0</strong></td>
<td><strong>35.7</strong></td>
<td><strong>36.0</strong></td>
<td><strong>27080.4</strong></td>
<td><strong>368.0</strong></td>
<td><strong>333.5</strong></td>
<td><strong>5.1</strong></td>
<td><strong>1.44</strong></td>
<td><strong>0.52</strong></td>
</tr>
<tr class="even">
<td>.125</td>
<td>39.0</td>
<td>39.0</td>
<td>35.7</td>
<td>33.4</td>
<td>26960.9</td>
<td>231.7</td>
<td>336.0</td>
<td>11.0</td>
<td>1.54</td>
<td>0.59</td>
</tr>
<tr class="odd">
<td>.25</td>
<td>39.0</td>
<td>39.0</td>
<td>35.7</td>
<td>33.1</td>
<td>26753.6</td>
<td>247.9</td>
<td>332.1</td>
<td>10.2</td>
<td>2.34</td>
<td>1.61</td>
</tr>
<tr class="even">
<td>.5</td>
<td>39.0</td>
<td>39.0</td>
<td>35.7</td>
<td>31.7</td>
<td>26867.0</td>
<td>296.9</td>
<td>328.3</td>
<td>8.7</td>
<td>2.15</td>
<td>0.93</td>
</tr>
<tr class="odd">
<td>.75</td>
<td>39.0</td>
<td>39.0</td>
<td>35.1</td>
<td>31.5</td>
<td>26913.9</td>
<td>256.2</td>
<td>320.0</td>
<td>10.7</td>
<td>1.48</td>
<td>0.77</td>
</tr>
<tr class="even">
<td colspan="12">Case II – Heterogeneous Fleet (CV, GB) (n = 10, 1000
requests/day)</td>
</tr>
<tr class="odd">
<td rowspan="5">210</td>
<td><strong>0</strong></td>
<td></td>
<td><strong>78.6</strong></td>
<td><strong>104.9</strong></td>
<td></td>
<td><strong>29838.3</strong></td>
<td><strong>606.9</strong></td>
<td><strong>422.2</strong></td>
<td><strong>16.9</strong></td>
<td><strong>1.94</strong></td>
<td><strong>0.43</strong></td>
</tr>
<tr class="even">
<td>.125</td>
<td></td>
<td>105.0</td>
<td>77.8</td>
<td></td>
<td>29795.5</td>
<td>587.5</td>
<td>425.8</td>
<td>18.4</td>
<td>2.44</td>
<td>0.43</td>
</tr>
<tr class="odd">
<td>.25</td>
<td></td>
<td>105.0</td>
<td>74.8</td>
<td></td>
<td>29614.4</td>
<td>685.6</td>
<td>414.0</td>
<td>19.9</td>
<td>2.31</td>
<td>0.79</td>
</tr>
<tr class="even">
<td>.5</td>
<td></td>
<td>104.9</td>
<td>67.7</td>
<td></td>
<td>28959.7</td>
<td>490.7</td>
<td>398.9</td>
<td>7.9</td>
<td>2.03</td>
<td>0.29</td>
</tr>
<tr class="odd">
<td>.75</td>
<td></td>
<td>104.9</td>
<td>65.4</td>
<td></td>
<td>29386.7</td>
<td>587.0</td>
<td>386.3</td>
<td>14.1</td>
<td>2.11</td>
<td>0.53</td>
</tr>
<tr class="even">
<td rowspan="5">180</td>
<td><strong>0</strong></td>
<td></td>
<td><strong>82.8</strong></td>
<td><strong>90.0</strong></td>
<td></td>
<td><strong>29188.7</strong></td>
<td><strong>516.2</strong></td>
<td><strong>398.4</strong></td>
<td><strong>12.4</strong></td>
<td><strong>1.98</strong></td>
<td><strong>0.53</strong></td>
</tr>
<tr class="odd">
<td>.125</td>
<td></td>
<td>90.0</td>
<td>82.9</td>
<td></td>
<td>29190.3</td>
<td>413.2</td>
<td>401.3</td>
<td>9.5</td>
<td>1.89</td>
<td>0.36</td>
</tr>
<tr class="even">
<td>.25</td>
<td></td>
<td>90.0</td>
<td>82.3</td>
<td></td>
<td>29107.5</td>
<td>477.8</td>
<td>399.2</td>
<td>9.7</td>
<td>2.32</td>
<td>0.95</td>
</tr>
<tr class="odd">
<td>.5</td>
<td></td>
<td>90.0</td>
<td>78.2</td>
<td></td>
<td>28752.1</td>
<td>363.2</td>
<td>385.6</td>
<td>10.6</td>
<td>2.26</td>
<td>0.86</td>
</tr>
<tr class="even">
<td>.75</td>
<td></td>
<td>89.9</td>
<td>75.5</td>
<td></td>
<td>28999.0</td>
<td>561.1</td>
<td>370.6</td>
<td>11.0</td>
<td>2.02</td>
<td>0.64</td>
</tr>
<tr class="odd">
<td rowspan="5">150</td>
<td><strong>0</strong></td>
<td></td>
<td><strong>73.0</strong></td>
<td><strong>75.0</strong></td>
<td></td>
<td><strong>27090.1</strong></td>
<td><strong>342.7</strong></td>
<td><strong>335.5</strong></td>
<td><strong>9.6</strong></td>
<td><strong>1.85</strong></td>
<td><strong>0.68</strong></td>
</tr>
<tr class="even">
<td>.125</td>
<td></td>
<td>75.0</td>
<td>73.1</td>
<td></td>
<td>27061.6</td>
<td>227.1</td>
<td>336.4</td>
<td>9.5</td>
<td>1.78</td>
<td>0.74</td>
</tr>
<tr class="odd">
<td>.25</td>
<td></td>
<td>75.0</td>
<td>73.1</td>
<td></td>
<td>27062.7</td>
<td>335.6</td>
<td>334.8</td>
<td>9.1</td>
<td>1.97</td>
<td>0.85</td>
</tr>
<tr class="even">
<td>.5</td>
<td></td>
<td>75.0</td>
<td>71.6</td>
<td></td>
<td>26852.6</td>
<td>274.9</td>
<td>334.5</td>
<td>4.8</td>
<td>2.15</td>
<td>0.84</td>
</tr>
<tr class="odd">
<td>.75</td>
<td></td>
<td>75.0</td>
<td>70.2</td>
<td></td>
<td>27065.5</td>
<td>288.5</td>
<td>322.7</td>
<td>6.4</td>
<td>1.49</td>
<td>0.56</td>
</tr>
<tr class="even">
<td colspan="12">Case III – Homogeneous Fleet (GB) (n = 10, 1000
requests/day)</td>
</tr>
<tr class="odd">
<td rowspan="5">210</td>
<td><strong>0</strong></td>
<td></td>
<td></td>
<td><strong>183.8</strong></td>
<td></td>
<td><strong>29904.2</strong></td>
<td><strong>832.8</strong></td>
<td><strong>425.6</strong></td>
<td><strong>15.7</strong></td>
<td><strong>2.24</strong></td>
<td><strong>0.75</strong></td>
</tr>
<tr class="even">
<td>.125</td>
<td></td>
<td></td>
<td>183.4</td>
<td></td>
<td>29695.1</td>
<td>692.3</td>
<td>421.3</td>
<td>15.7</td>
<td>2.20</td>
<td>0.46</td>
</tr>
<tr class="odd">
<td>.25</td>
<td></td>
<td></td>
<td>181.5</td>
<td></td>
<td>29668.5</td>
<td>648.6</td>
<td>420.3</td>
<td>15.5</td>
<td>2.44</td>
<td>0.78</td>
</tr>
<tr class="even">
<td>.5</td>
<td></td>
<td></td>
<td>176.8</td>
<td></td>
<td>29271.0</td>
<td>721.0</td>
<td>406.7</td>
<td>15.5</td>
<td>2.42</td>
<td>0.63</td>
</tr>
<tr class="odd">
<td>.75</td>
<td></td>
<td></td>
<td>178.2</td>
<td></td>
<td>29925.5</td>
<td>689.8</td>
<td>401.1</td>
<td>13.0</td>
<td>2.01</td>
<td>0.66</td>
</tr>
<tr class="even">
<td rowspan="5">180</td>
<td><strong>0</strong></td>
<td></td>
<td></td>
<td><strong>173.1</strong></td>
<td></td>
<td><strong>29142.9</strong></td>
<td><strong>447.2</strong></td>
<td><strong>396.6</strong></td>
<td><strong>11.9</strong></td>
<td><strong>2.01</strong></td>
<td><strong>0.66</strong></td>
</tr>
<tr class="odd">
<td>.125</td>
<td></td>
<td></td>
<td>172.7</td>
<td></td>
<td>28977.7</td>
<td>417.7</td>
<td>397.1</td>
<td>12.0</td>
<td>2.32</td>
<td>0.55</td>
</tr>
<tr class="even">
<td>.25</td>
<td></td>
<td></td>
<td>172.3</td>
<td></td>
<td>28954.6</td>
<td>457.0</td>
<td>400.7</td>
<td>9.0</td>
<td>2.02</td>
<td>0.45</td>
</tr>
<tr class="odd">
<td>.5</td>
<td></td>
<td></td>
<td>171.0</td>
<td></td>
<td>28869.7</td>
<td>340.0</td>
<td>393.3</td>
<td>7.2</td>
<td>2.42</td>
<td>0.82</td>
</tr>
<tr class="even">
<td>.75</td>
<td></td>
<td></td>
<td>170.6</td>
<td></td>
<td>29462.5</td>
<td>478.2</td>
<td>382.7</td>
<td>10.5</td>
<td>2.05</td>
<td>0.70</td>
</tr>
<tr class="odd">
<td rowspan="5">150</td>
<td><strong>0</strong></td>
<td></td>
<td></td>
<td><strong>148.1</strong></td>
<td></td>
<td><strong>27105.0</strong></td>
<td><strong>262.7</strong></td>
<td><strong>334.5</strong></td>
<td><strong>4.4</strong></td>
<td><strong>1.71</strong></td>
<td><strong>0.49</strong></td>
</tr>
<tr class="even">
<td>.125</td>
<td></td>
<td></td>
<td>148.4</td>
<td></td>
<td>27096.7</td>
<td>277.1</td>
<td>332.2</td>
<td>6.5</td>
<td>1.81</td>
<td>0.61</td>
</tr>
<tr class="odd">
<td>.25</td>
<td></td>
<td></td>
<td>148.1</td>
<td></td>
<td>27047.1</td>
<td>303.5</td>
<td>334.7</td>
<td>7.6</td>
<td>1.99</td>
<td>0.59</td>
</tr>
<tr class="even">
<td>.5</td>
<td></td>
<td></td>
<td>147.7</td>
<td></td>
<td>26952.3</td>
<td>356.5</td>
<td>335.3</td>
<td>6.2</td>
<td>1.74</td>
<td>0.52</td>
</tr>
<tr class="odd">
<td>.75</td>
<td></td>
<td></td>
<td>146.6</td>
<td></td>
<td>27262.3</td>
<td>442.1</td>
<td>324.6</td>
<td>8.1</td>
<td>1.99</td>
<td>0.71</td>
</tr>
<tr class="even">
<td colspan="12"><ol type="1">
<li><p>Engine idling includes only that during waiting and not that
during passenger loading/unloading, as the former is<br />
controllable and a function of vehicle itinerary whereas the latter is
not.</p></li>
</ol></td>
</tr>
</tbody>
</table>

<table>
<colgroup>
<col style="width: 12%" />
<col style="width: 7%" />
<col style="width: 9%" />
<col style="width: 9%" />
<col style="width: 9%" />
<col style="width: 8%" />
<col style="width: 8%" />
<col style="width: 11%" />
<col style="width: 8%" />
<col style="width: 8%" />
<col style="width: 9%" />
</colgroup>
<tbody>
<tr class="odd">
<td colspan="11"><strong>Table 10a. Scheduling Algorithm
Results--Life-Cycle Criteria and Other Pollutant Air
Emissions</strong></td>
</tr>
<tr class="even">
<td><p><u>Fleet Size</u></p>
<p><u>(Tot. Veh.)</u></p></td>
<td><u>W<sub>env</sub></u></td>
<td><u>VOC (kg)</u></td>
<td><p><u>Air Toxics</u></p>
<p><u>(kg)<sup>(1)</sup></u></p></td>
<td><p><u>SOx</u></p>
<p><u>(kg)</u></p></td>
<td><p><u>NOx</u></p>
<p><u>(kg)</u></p></td>
<td><p><u>CO</u></p>
<p><u>(kg)</u></p></td>
<td><p><u>CO2-Equiv.</u></p>
<p><u>(kg/1000)</u></p></td>
<td><p><u>CH4</u></p>
<p><u>(kg)</u></p></td>
<td><p><u>PM10</u></p>
<p><u>(kg)</u></p></td>
<td><p><u>DPM10</u></p>
<p><u>(kg)</u></p></td>
</tr>
<tr class="odd">
<td colspan="11">Case I – Heterogeneous Fleet (CV, GV, GB, DB) (n = 10,
1000 requests/day)</td>
</tr>
<tr class="even">
<td rowspan="5">210</td>
<td><strong>0</strong></td>
<td><strong>19.84</strong></td>
<td><strong>1.24</strong></td>
<td><strong>32.26</strong></td>
<td><strong>73.05</strong></td>
<td><strong>103.66</strong></td>
<td><strong>28.91</strong></td>
<td><strong>26.38</strong></td>
<td><strong>4.38</strong></td>
<td><strong>0.53</strong></td>
</tr>
<tr class="odd">
<td>.125</td>
<td>17.00</td>
<td>0.93</td>
<td>31.04</td>
<td>54.76</td>
<td>105.74</td>
<td>29.03</td>
<td>62.34</td>
<td>4.51</td>
<td>0.16</td>
</tr>
<tr class="even">
<td>.25</td>
<td>16.46</td>
<td>0.88</td>
<td>30.51</td>
<td>52.07</td>
<td>104.68</td>
<td>28.62</td>
<td>63.09</td>
<td>4.46</td>
<td>0.12</td>
</tr>
<tr class="odd">
<td>.5</td>
<td>16.09</td>
<td>0.85</td>
<td>30.21</td>
<td>50.11</td>
<td>103.86</td>
<td>28.38</td>
<td>64.65</td>
<td>4.44</td>
<td>0.09</td>
</tr>
<tr class="even">
<td>.75</td>
<td>16.32</td>
<td>0.86</td>
<td>30.58</td>
<td>50.93</td>
<td>104.77</td>
<td>28.69</td>
<td>65.24</td>
<td>4.48</td>
<td>0.10</td>
</tr>
<tr class="odd">
<td rowspan="5">180</td>
<td><strong>0</strong></td>
<td><strong>19.21</strong></td>
<td><strong>1.18</strong></td>
<td><strong>31.35</strong></td>
<td><strong>69.85</strong></td>
<td><strong>101.48</strong></td>
<td><strong>28.49</strong></td>
<td><strong>38.58</strong></td>
<td><strong>4.32</strong></td>
<td><strong>0.47</strong></td>
</tr>
<tr class="even">
<td>.125</td>
<td>17.81</td>
<td>1.02</td>
<td>30.75</td>
<td>60.79</td>
<td>102.84</td>
<td>28.58</td>
<td>56.48</td>
<td>4.39</td>
<td>0.28</td>
</tr>
<tr class="odd">
<td>.25</td>
<td>17.38</td>
<td>0.99</td>
<td>30.37</td>
<td>58.65</td>
<td>102.41</td>
<td>28.31</td>
<td>56.87</td>
<td>4.35</td>
<td>0.25</td>
</tr>
<tr class="even">
<td>.5</td>
<td>16.79</td>
<td>0.94</td>
<td>29.89</td>
<td>55.54</td>
<td>102.00</td>
<td>27.99</td>
<td>57.90</td>
<td>4.32</td>
<td>0.20</td>
</tr>
<tr class="odd">
<td>.75</td>
<td>17.24</td>
<td>0.97</td>
<td>30.46</td>
<td>57.47</td>
<td>102.82</td>
<td>28.41</td>
<td>58.55</td>
<td>4.38</td>
<td>0.23</td>
</tr>
<tr class="even">
<td rowspan="5">150</td>
<td><strong>0</strong></td>
<td><strong>17.83</strong></td>
<td><strong>1.09</strong></td>
<td><strong>29.10</strong></td>
<td><strong>64.55</strong></td>
<td><strong>94.96</strong></td>
<td><strong>26.71</strong></td>
<td><strong>41.87</strong></td>
<td><strong>4.04</strong></td>
<td><strong>0.41</strong></td>
</tr>
<tr class="odd">
<td>.125</td>
<td>17.22</td>
<td>1.02</td>
<td>28.80</td>
<td>60.70</td>
<td>95.34</td>
<td>26.69</td>
<td>49.03</td>
<td>4.06</td>
<td>0.34</td>
</tr>
<tr class="even">
<td>.25</td>
<td>17.00</td>
<td>1.01</td>
<td>28.57</td>
<td>59.65</td>
<td>94.82</td>
<td>26.50</td>
<td>49.38</td>
<td>4.04</td>
<td>0.32</td>
</tr>
<tr class="odd">
<td>.5</td>
<td>16.99</td>
<td>1.00</td>
<td>28.69</td>
<td>59.31</td>
<td>95.60</td>
<td>26.64</td>
<td>49.76</td>
<td>4.06</td>
<td>0.31</td>
</tr>
<tr class="even">
<td>.75</td>
<td>16.96</td>
<td>0.99</td>
<td>28.72</td>
<td>59.05</td>
<td>95.50</td>
<td>26.65</td>
<td>50.29</td>
<td>4.07</td>
<td>0.31</td>
</tr>
<tr class="odd">
<td colspan="11">Case II – Heterogeneous Fleet (CV, GB) (n = 10, 1000
requests/day)</td>
</tr>
<tr class="even">
<td rowspan="5">210</td>
<td><strong>0</strong></td>
<td><strong>18.42</strong></td>
<td><strong>1.29</strong></td>
<td><strong>32.89</strong></td>
<td><strong>60.22</strong></td>
<td><strong>146.23</strong></td>
<td><strong>34.87</strong></td>
<td><strong>72.73</strong></td>
<td><strong>5.16</strong></td>
<td><strong>0.00</strong></td>
</tr>
<tr class="odd">
<td>.125</td>
<td>17.69</td>
<td>1.00</td>
<td>30.64</td>
<td>56.36</td>
<td>118.14</td>
<td>31.89</td>
<td>124.50</td>
<td>4.82</td>
<td>0.00</td>
</tr>
<tr class="even">
<td>.25</td>
<td>17.55</td>
<td>0.98</td>
<td>30.37</td>
<td>55.87</td>
<td>116.38</td>
<td>31.59</td>
<td>125.65</td>
<td>4.78</td>
<td>0.00</td>
</tr>
<tr class="odd">
<td>.5</td>
<td>17.11</td>
<td>0.94</td>
<td>29.54</td>
<td>54.35</td>
<td>111.71</td>
<td>30.68</td>
<td>126.63</td>
<td>4.65</td>
<td>0.00</td>
</tr>
<tr class="even">
<td>.75</td>
<td>17.34</td>
<td>0.95</td>
<td>29.91</td>
<td>55.03</td>
<td>112.45</td>
<td>31.04</td>
<td>130.13</td>
<td>4.71</td>
<td>0.00</td>
</tr>
<tr class="odd">
<td rowspan="5">180</td>
<td><strong>0</strong></td>
<td><strong>17.84</strong></td>
<td><strong>1.19</strong></td>
<td><strong>31.65</strong></td>
<td><strong>57.99</strong></td>
<td><strong>136.34</strong></td>
<td><strong>33.42</strong></td>
<td><strong>83.46</strong></td>
<td><strong>4.97</strong></td>
<td><strong>0.00</strong></td>
</tr>
<tr class="even">
<td>.125</td>
<td>17.51</td>
<td>1.06</td>
<td>30.59</td>
<td>56.19</td>
<td>123.01</td>
<td>32.01</td>
<td>108.40</td>
<td>4.81</td>
<td>0.00</td>
</tr>
<tr class="odd">
<td>.25</td>
<td>17.45</td>
<td>1.05</td>
<td>30.47</td>
<td>55.96</td>
<td>122.12</td>
<td>31.86</td>
<td>109.08</td>
<td>4.79</td>
<td>0.00</td>
</tr>
<tr class="even">
<td>.5</td>
<td>17.20</td>
<td>1.02</td>
<td>29.97</td>
<td>55.07</td>
<td>119.09</td>
<td>31.31</td>
<td>110.57</td>
<td>4.71</td>
<td>0.00</td>
</tr>
<tr class="odd">
<td>.75</td>
<td>17.32</td>
<td>1.02</td>
<td>30.18</td>
<td>55.45</td>
<td>119.45</td>
<td>31.52</td>
<td>112.66</td>
<td>4.75</td>
<td>0.00</td>
</tr>
<tr class="even">
<td rowspan="5">150</td>
<td><strong>0</strong></td>
<td><strong>16.46</strong></td>
<td><strong>1.07</strong></td>
<td><strong>29.10</strong></td>
<td><strong>53.33</strong></td>
<td><strong>122.88</strong></td>
<td><strong>30.64</strong></td>
<td><strong>83.98</strong></td>
<td><strong>4.57</strong></td>
<td><strong>0.00</strong></td>
</tr>
<tr class="odd">
<td>.125</td>
<td>16.32</td>
<td>1.01</td>
<td>28.65</td>
<td>52.56</td>
<td>117.50</td>
<td>30.05</td>
<td>93.75</td>
<td>4.50</td>
<td>0.00</td>
</tr>
<tr class="even">
<td>.25</td>
<td>16.31</td>
<td>1.01</td>
<td>28.63</td>
<td>52.54</td>
<td>117.32</td>
<td>30.04</td>
<td>94.11</td>
<td>4.50</td>
<td>0.00</td>
</tr>
<tr class="odd">
<td>.5</td>
<td>16.17</td>
<td>1.00</td>
<td>28.36</td>
<td>52.04</td>
<td>115.73</td>
<td>29.73</td>
<td>94.69</td>
<td>4.46</td>
<td>0.00</td>
</tr>
<tr class="even">
<td>.75</td>
<td>16.28</td>
<td>1.00</td>
<td>28.53</td>
<td>52.35</td>
<td>115.93</td>
<td>29.89</td>
<td>96.67</td>
<td>4.48</td>
<td>0.00</td>
</tr>
<tr class="odd">
<td colspan="11">Case III – Homogeneous Fleet (GB) (n = 10, 1000
requests/day)</td>
</tr>
<tr class="even">
<td rowspan="5">210</td>
<td><strong>0</strong></td>
<td><strong>19.48</strong></td>
<td><strong>1.70</strong></td>
<td><strong>36.01</strong></td>
<td><strong>65.69</strong></td>
<td><strong>185.92</strong></td>
<td><strong>39.01</strong></td>
<td><strong>0.95</strong></td>
<td><strong>5.63</strong></td>
<td><strong>0.00</strong></td>
</tr>
<tr class="odd">
<td>.125</td>
<td>19.34</td>
<td>1.69</td>
<td>35.76</td>
<td>65.23</td>
<td>184.61</td>
<td>38.74</td>
<td>0.94</td>
<td>5.59</td>
<td>0.00</td>
</tr>
<tr class="even">
<td>.25</td>
<td>19.32</td>
<td>1.69</td>
<td>35.73</td>
<td>65.17</td>
<td>184.45</td>
<td>38.71</td>
<td>0.94</td>
<td>5.58</td>
<td>0.00</td>
</tr>
<tr class="odd">
<td>.5</td>
<td>19.06</td>
<td>1.67</td>
<td>35.25</td>
<td>64.29</td>
<td>181.92</td>
<td>38.19</td>
<td>0.93</td>
<td>5.51</td>
<td>0.00</td>
</tr>
<tr class="even">
<td>.75</td>
<td>19.48</td>
<td>1.70</td>
<td>36.03</td>
<td>65.70</td>
<td>185.82</td>
<td>39.04</td>
<td>0.95</td>
<td>5.63</td>
<td>0.00</td>
</tr>
<tr class="odd">
<td rowspan="5">180</td>
<td><strong>0</strong></td>
<td><strong>18.97</strong></td>
<td><strong>1.66</strong></td>
<td><strong>35.09</strong></td>
<td><strong>63.99</strong></td>
<td><strong>181.04</strong></td>
<td><strong>38.02</strong></td>
<td><strong>0.92</strong></td>
<td><strong>5.48</strong></td>
<td><strong>0.00</strong></td>
</tr>
<tr class="even">
<td>.125</td>
<td>18.87</td>
<td>1.65</td>
<td>34.89</td>
<td>63.63</td>
<td>180.05</td>
<td>37.80</td>
<td>0.92</td>
<td>5.45</td>
<td>0.00</td>
</tr>
<tr class="odd">
<td>.25</td>
<td>18.85</td>
<td>1.65</td>
<td>34.86</td>
<td>63.59</td>
<td>179.94</td>
<td>37.78</td>
<td>0.92</td>
<td>5.45</td>
<td>0.00</td>
</tr>
<tr class="even">
<td>.5</td>
<td>18.79</td>
<td>1.64</td>
<td>34.76</td>
<td>63.39</td>
<td>179.36</td>
<td>37.66</td>
<td>0.92</td>
<td>5.43</td>
<td>0.00</td>
</tr>
<tr class="odd">
<td>.75</td>
<td>19.17</td>
<td>1.67</td>
<td>35.47</td>
<td>64.67</td>
<td>182.84</td>
<td>38.43</td>
<td>0.93</td>
<td>5.54</td>
<td>0.00</td>
</tr>
<tr class="even">
<td rowspan="5">150</td>
<td><strong>0</strong></td>
<td><strong>17.63</strong></td>
<td><strong>1.54</strong></td>
<td><strong>32.64</strong></td>
<td><strong>59.47</strong></td>
<td><strong>168.10</strong></td>
<td><strong>35.36</strong></td>
<td><strong>0.86</strong></td>
<td><strong>5.10</strong></td>
<td><strong>0.00</strong></td>
</tr>
<tr class="odd">
<td>.125</td>
<td>17.62</td>
<td>1.54</td>
<td>32.63</td>
<td>59.45</td>
<td>168.03</td>
<td>35.35</td>
<td>0.86</td>
<td>5.10</td>
<td>0.00</td>
</tr>
<tr class="even">
<td>.25</td>
<td>17.59</td>
<td>1.53</td>
<td>32.57</td>
<td>59.35</td>
<td>167.75</td>
<td>35.28</td>
<td>0.86</td>
<td>5.09</td>
<td>0.00</td>
</tr>
<tr class="odd">
<td>.5</td>
<td>17.53</td>
<td>1.53</td>
<td>32.45</td>
<td>59.14</td>
<td>167.17</td>
<td>35.16</td>
<td>0.85</td>
<td>5.07</td>
<td>0.00</td>
</tr>
<tr class="even">
<td>.75</td>
<td>17.72</td>
<td>1.54</td>
<td>32.82</td>
<td>59.80</td>
<td>168.92</td>
<td>35.56</td>
<td>0.86</td>
<td>5.13</td>
<td>0.00</td>
</tr>
<tr class="odd">
<td colspan="11">(1) Includes formaldehyde, 1,4-butadiene, acetaldehyde,
toluene, benzene, and MTBE</td>
</tr>
</tbody>
</table>

+-------+----+-------+-------+-------+-------+-------+-------+-------+
| **    |    |       |       |       |       |       |       |       |
| Table |    |       |       |       |       |       |       |       |
| 10b.  |    |       |       |       |       |       |       |       |
| Sched |    |       |       |       |       |       |       |       |
| uling |    |       |       |       |       |       |       |       |
| Algo  |    |       |       |       |       |       |       |       |
| rithm |    |       |       |       |       |       |       |       |
| Resul |    |       |       |       |       |       |       |       |
| ts--- |    |       |       |       |       |       |       |       |
| Other |    |       |       |       |       |       |       |       |
| Life- |    |       |       |       |       |       |       |       |
| Cycle |    |       |       |       |       |       |       |       |
| Impa  |    |       |       |       |       |       |       |       |
| cts** |    |       |       |       |       |       |       |       |
+-------+----+-------+-------+-------+-------+-------+-------+-------+
| [     | [W | [TR   | [RCRA | [     | [Ener | [Fuel | [Base | [     |
| Fleet | ~e | I/]{. | Was   | Solid | gy]{. | Con   | Met   | Prec. |
| Si    | nv | under | te]{. | Was   | under | s.]{. | al]{. | Met   |
| ze]{. | ~] | line} | under | te]{. | line} | under | under | al]{. |
| under | {. |       | line} | under |       | line} | line} | under |
| line} | un | [SA   |       | line} | [Con  |       |       | line} |
|       | de | RA]{. | [Gen. |       | s.]{. | [(gal | [     |       |
| [     | rl | under | (k    | [Gen. | under | .)^(1 | Cons. | [     |
| (Tot. | in | line} | g)]{. | (k    | line} | )^]{. | (k    | Cons. |
| Veh   | e} |       | under | g)]{. |       | under | g)]{. | (k    |
| .)]{. |    | [     | line} | under | [(M   | line} | under | g)]{. |
| under |    | Emis. |       | line} | J/100 |       | line} | under |
| line} |    | (k    |       |       | 0)]{. |       |       | line} |
|       |    | g)]{. |       |       | under |       |       |       |
|       |    | under |       |       | line} |       |       |       |
|       |    | line} |       |       |       |       |       |       |
+-------+----+-------+-------+-------+-------+-------+-------+-------+
| Case  |    |       |       |       |       |       |       |       |
| I --  |    |       |       |       |       |       |       |       |
| Het   |    |       |       |       |       |       |       |       |
| eroge |    |       |       |       |       |       |       |       |
| neous |    |       |       |       |       |       |       |       |
| Fleet |    |       |       |       |       |       |       |       |
| (CV,  |    |       |       |       |       |       |       |       |
| GV,   |    |       |       |       |       |       |       |       |
| GB,   |    |       |       |       |       |       |       |       |
| DB)   |    |       |       |       |       |       |       |       |
| (n =  |    |       |       |       |       |       |       |       |
| 10,   |    |       |       |       |       |       |       |       |
| 1000  |    |       |       |       |       |       |       |       |
| req   |    |       |       |       |       |       |       |       |
| uests |    |       |       |       |       |       |       |       |
| /day) |    |       |       |       |       |       |       |       |
+-------+----+-------+-------+-------+-------+-------+-------+-------+
| 210   | *  | **1   | **43  | **165 | **254 | *     | *     | **369 |
|       | *0 | .22** | .37** | .55** | .27** | *1631 | *1941 | .91** |
|       | ** |       |       |       |       | .70** | .55** |       |
+-------+----+-------+-------+-------+-------+-------+-------+-------+
|       | .1 | 1.22  | 43.37 | 1     | 2     | 16    | 19    | 3     |
|       | 25 |       |       | 55.65 | 52.29 | 57.60 | 46.92 | 71.03 |
+-------+----+-------+-------+-------+-------+-------+-------+-------+
|       | .  | 1.20  | 42.70 | 1     | 2     | 16    | 19    | 3     |
|       | 25 |       |       | 52.15 | 48.90 | 39.80 | 16.23 | 65.17 |
+-------+----+-------+-------+-------+-------+-------+-------+-------+
|       | .5 | 1.19  | 42.40 | 1     | 2     | 16    | 19    | 3     |
|       |    |       |       | 50.22 | 46.56 | 27.20 | 03.72 | 62.80 |
+-------+----+-------+-------+-------+-------+-------+-------+-------+
|       | .  | 1.21  | 42.93 | 1     | 2     | 16    | 19    | 3     |
|       | 75 |       |       | 52.24 | 48.99 | 42.50 | 28.26 | 67.49 |
+-------+----+-------+-------+-------+-------+-------+-------+-------+
| 180   | *  | **1   | **42  | **162 | **248 | *     | *     | **364 |
|       | *0 | .20** | .68** | .14** | .85** | *1600 | *1914 | .75** |
|       | ** |       |       |       |       | .80** | .29** |       |
+-------+----+-------+-------+-------+-------+-------+-------+-------+
|       | .1 | 1.20  | 42.69 | 1     | 2     | 16    | 19    | 3     |
|       | 25 |       |       | 57.24 | 48.27 | 16.40 | 16.80 | 65.27 |
+-------+----+-------+-------+-------+-------+-------+-------+-------+
|       | .  | 1.18  | 42.20 | 1     | 2     | 16    | 18    | 3     |
|       | 25 |       |       | 54.53 | 46.25 | 07.00 | 93.40 | 60.80 |
+-------+----+-------+-------+-------+-------+-------+-------+-------+
|       | .5 | 1.17  | 41.61 | 1     | 2     | 15    | 18    | 3     |
|       |    |       |       | 50.99 | 43.82 | 97.00 | 65.77 | 55.53 |
+-------+----+-------+-------+-------+-------+-------+-------+-------+
|       | .  | 1.19  | 42.42 | 1     | 2     | 16    | 19    | 3     |
|       | 75 |       |       | 54.53 | 46.88 | 13.80 | 04.40 | 62.91 |
+-------+----+-------+-------+-------+-------+-------+-------+-------+
| 150   | *  | **1   | **39  | **151 | **232 | *     | *     | **340 |
|       | *0 | .12** | .84** | .10** | .90** | *1500 | *1786 | .46** |
|       | ** |       |       |       |       | .30** | .83** |       |
+-------+----+-------+-------+-------+-------+-------+-------+-------+
|       | .1 | 1.12  | 39.78 | 1     | 2     | 15    | 17    | 3     |
|       | 25 |       |       | 48.82 | 32.12 | 03.10 | 85.03 | 40.14 |
+-------+----+-------+-------+-------+-------+-------+-------+-------+
|       | .  | 1.11  | 39.49 | 1     | 2     | 14    | 17    | 3     |
|       | 25 |       |       | 47.38 | 30.43 | 93.40 | 71.94 | 37.64 |
+-------+----+-------+-------+-------+-------+-------+-------+-------+
|       | .5 | 1.11  | 39.66 | 1     | 2     | 15    | 17    | 3     |
|       |    |       |       | 47.66 | 31.91 | 04.90 | 79.24 | 39.03 |
+-------+----+-------+-------+-------+-------+-------+-------+-------+
|       | .  | 1.11  | 39.74 | 1     | 2     | 15    | 17    | 3     |
|       | 75 |       |       | 47.76 | 31.80 | 04.20 | 83.35 | 39.82 |
+-------+----+-------+-------+-------+-------+-------+-------+-------+
| Case  |    |       |       |       |       |       |       |       |
| II -- |    |       |       |       |       |       |       |       |
| Het   |    |       |       |       |       |       |       |       |
| eroge |    |       |       |       |       |       |       |       |
| neous |    |       |       |       |       |       |       |       |
| Fleet |    |       |       |       |       |       |       |       |
| (CV,  |    |       |       |       |       |       |       |       |
| GB)   |    |       |       |       |       |       |       |       |
| (n =  |    |       |       |       |       |       |       |       |
| 10,   |    |       |       |       |       |       |       |       |
| 1000  |    |       |       |       |       |       |       |       |
| req   |    |       |       |       |       |       |       |       |
| uests |    |       |       |       |       |       |       |       |
| /day) |    |       |       |       |       |       |       |       |
+-------+----+-------+-------+-------+-------+-------+-------+-------+
| 210   | *  | **1   | **44  | **150 | **217 | *     | *     | **387 |
|       | *0 | .27** | .16** | .66** | .45** | *1433 | *2028 | .27** |
|       | ** |       |       |       |       | .50** | .78** |       |
+-------+----+-------+-------+-------+-------+-------+-------+-------+
|       | .1 | 1.26  | 44.02 | 1     | 2     | 14    | 20    | 3     |
|       | 25 |       |       | 50.09 | 16.88 | 30.00 | 22.00 | 85.97 |
+-------+----+-------+-------+-------+-------+-------+-------+-------+
|       | .  | 1.26  | 44.00 | 1     | 2     | 14    | 20    | 3     |
|       | 25 |       |       | 50.02 | 16.80 | 29.40 | 21.14 | 85.80 |
+-------+----+-------+-------+-------+-------+-------+-------+-------+
|       | .5 | 1.25  | 43.53 | 1     | 2     | 14    | 19    | 3     |
|       |    |       |       | 48.23 | 14.74 | 16.10 | 98.90 | 81.56 |
+-------+----+-------+-------+-------+-------+-------+-------+-------+
|       | .  | 1.24  | 43.33 | 1     | 2     | 14    | 19    | 3     |
|       | 75 |       |       | 47.25 | 14.14 | 13.00 | 88.62 | 79.59 |
+-------+----+-------+-------+-------+-------+-------+-------+-------+
| 180   | *  | **1   | **43  | **149 | **213 | *     | *     | **382 |
|       | *0 | .25** | .57** | .75** | .02** | *1401 | *2005 | .82** |
|       | ** |       |       |       |       | .30** | .35** |       |
+-------+----+-------+-------+-------+-------+-------+-------+-------+
|       | .1 | 1.25  | 43.48 | 1     | 2     | 13    | 20    | 3     |
|       | 25 |       |       | 49.39 | 12.72 | 99.60 | 01.31 | 82.05 |
+-------+----+-------+-------+-------+-------+-------+-------+-------+
|       | .  | 1.25  | 43.49 | 1     | 2     | 14    | 20    | 3     |
|       | 25 |       |       | 49.38 | 12.81 | 00.40 | 01.52 | 82.09 |
+-------+----+-------+-------+-------+-------+-------+-------+-------+
|       | .5 | 1.23  | 42.85 | 1     | 2     | 13    | 19    | 3     |
|       |    |       |       | 47.03 | 09.92 | 81.70 | 71.63 | 76.38 |
+-------+----+-------+-------+-------+-------+-------+-------+-------+
|       | .  | 1.25  | 43.39 | 1     | 2     | 13    | 19    | 3     |
|       | 75 |       |       | 48.76 | 12.66 | 99.90 | 95.85 | 81.00 |
+-------+----+-------+-------+-------+-------+-------+-------+-------+
| 150   | *  | **1   | **40  | **139 | **196 | *     | *     | **355 |
|       | *0 | .16** | .43** | .53** | .95** | *1294 | *1862 | .65** |
|       | ** |       |       |       |       | .20** | .97** |       |
+-------+----+-------+-------+-------+-------+-------+-------+-------+
|       | .1 | 1.17  | 40.55 | 1     | 1     | 12    | 18    | 3     |
|       | 25 |       |       | 39.93 | 97.51 | 97.90 | 68.29 | 56.67 |
+-------+----+-------+-------+-------+-------+-------+-------+-------+
|       | .  | 1.17  | 40.56 | 1     | 1     | 12    | 18    | 3     |
|       | 25 |       |       | 39.98 | 97.62 | 98.80 | 69.08 | 56.82 |
+-------+----+-------+-------+-------+-------+-------+-------+-------+
|       | .5 | 1.16  | 40.23 | 1     | 1     | 12    | 18    | 3     |
|       |    |       |       | 38.76 | 96.02 | 88.30 | 53.28 | 53.80 |
+-------+----+-------+-------+-------+-------+-------+-------+-------+
|       | .  | 1.16  | 40.46 | 1     | 1     | 12    | 18    | 3     |
|       | 75 |       |       | 39.47 | 97.31 | 96.90 | 63.80 | 55.81 |
+-------+----+-------+-------+-------+-------+-------+-------+-------+
| Case  |    |       |       |       |       |       |       |       |
| III   |    |       |       |       |       |       |       |       |
| --    |    |       |       |       |       |       |       |       |
| H     |    |       |       |       |       |       |       |       |
| omoge |    |       |       |       |       |       |       |       |
| neous |    |       |       |       |       |       |       |       |
| Fleet |    |       |       |       |       |       |       |       |
| (GB)  |    |       |       |       |       |       |       |       |
| (n =  |    |       |       |       |       |       |       |       |
| 10,   |    |       |       |       |       |       |       |       |
| 1000  |    |       |       |       |       |       |       |       |
| req   |    |       |       |       |       |       |       |       |
| uests |    |       |       |       |       |       |       |       |
| /day) |    |       |       |       |       |       |       |       |
+-------+----+-------+-------+-------+-------+-------+-------+-------+
| 210   | *  | **1   | **43  | **155 | **393 | *     | *     | **340 |
|       | *0 | .14** | .93** | .20** | .29** | *2664 | *1798 | .50** |
|       | ** |       |       |       |       | .60** | .07** |       |
+-------+----+-------+-------+-------+-------+-------+-------+-------+
|       | .1 | 1.13  | 43.62 | 1     | 3     | 26    | 17    | 3     |
|       | 25 |       |       | 54.12 | 90.54 | 46.10 | 85.50 | 38.12 |
+-------+----+-------+-------+-------+-------+-------+-------+-------+
|       | .  | 1.13  | 43.58 | 1     | 3     | 26    | 17    | 3     |
|       | 25 |       |       | 53.98 | 90.19 | 43.70 | 83.90 | 37.81 |
+-------+----+-------+-------+-------+-------+-------+-------+-------+
|       | .5 | 1.11  | 42.99 | 1     | 3     | 26    | 17    | 3     |
|       |    |       |       | 51.92 | 84.95 | 08.30 | 59.99 | 33.29 |
+-------+----+-------+-------+-------+-------+-------+-------+-------+
|       | .  | 1.14  | 43.96 | 1     | 3     | 26    | 17    | 3     |
|       | 75 |       |       | 55.31 | 93.55 | 66.40 | 99.34 | 40.74 |
+-------+----+-------+-------+-------+-------+-------+-------+-------+
| 180   | *  | **1   | **42  | **151 | **383 | *     | *     | **331 |
|       | *0 | .11** | .81** | .25** | .26** | *2596 | *1752 | .83** |
|       | ** |       |       |       |       | .70** | .29** |       |
+-------+----+-------+-------+-------+-------+-------+-------+-------+
|       | .1 | 1.10  | 42.56 | 1     | 3     | 25    | 17    | 3     |
|       | 25 |       |       | 50.39 | 81.09 | 82.10 | 42.36 | 29.95 |
+-------+----+-------+-------+-------+-------+-------+-------+-------+
|       | .  | 1.10  | 42.53 | 1     | 3     | 25    | 17    | 3     |
|       | 25 |       |       | 50.27 | 80.79 | 80.00 | 40.97 | 29.68 |
+-------+----+-------+-------+-------+-------+-------+-------+-------+
|       | .5 | 1.10  | 42.41 | 1     | 3     | 25    | 17    | 3     |
|       |    |       |       | 49.83 | 79.67 | 72.30 | 35.87 | 28.72 |
+-------+----+-------+-------+-------+-------+-------+-------+-------+
|       | .  | 1.12  | 43.27 | 1     | 3     | 26    | 17    | 3     |
|       | 75 |       |       | 52.91 | 87.45 | 25.10 | 71.50 | 35.47 |
+-------+----+-------+-------+-------+-------+-------+-------+-------+
| 150   | *  | **1   | **39  | **140 | **356 | *     | *     | **308 |
|       | *0 | .03** | .81** | .68** | .44** | *2414 | *1629 | .62** |
|       | ** |       |       |       |       | .90** | .75** |       |
+-------+----+-------+-------+-------+-------+-------+-------+-------+
|       | .1 | 1.03  | 39.80 | 1     | 3     | 24    | 16    | 3     |
|       | 25 |       |       | 40.63 | 56.33 | 14.20 | 29.24 | 08.53 |
+-------+----+-------+-------+-------+-------+-------+-------+-------+
|       | .  | 1.03  | 39.73 | 1     | 3     | 24    | 16    | 3     |
|       | 25 |       |       | 40.37 | 55.68 | 09.70 | 26.27 | 07.96 |
+-------+----+-------+-------+-------+-------+-------+-------+-------+
|       | .5 | 1.02  | 39.59 | 1     | 3     | 24    | 16    | 3     |
|       |    |       |       | 39.88 | 54.43 | 01.40 | 20.57 | 06.88 |
+-------+----+-------+-------+-------+-------+-------+-------+-------+
|       | .  | 1.04  | 40.04 | 1     | 3     | 24    | 16    | 3     |
|       | 75 |       |       | 41.49 | 58.49 | 28.50 | 39.19 | 10.41 |
+-------+----+-------+-------+-------+-------+-------+-------+-------+
| \(1\) |    |       |       |       |       |       |       |       |
| Fuel  |    |       |       |       |       |       |       |       |
| c     |    |       |       |       |       |       |       |       |
| onsum |    |       |       |       |       |       |       |       |
| ption |    |       |       |       |       |       |       |       |
| in    |    |       |       |       |       |       |       |       |
| gaso  |    |       |       |       |       |       |       |       |
| line- |    |       |       |       |       |       |       |       |
| equiv |    |       |       |       |       |       |       |       |
| alent |    |       |       |       |       |       |       |       |
| ga    |    |       |       |       |       |       |       |       |
| llons |    |       |       |       |       |       |       |       |
+-------+----+-------+-------+-------+-------+-------+-------+-------+

<table>
<colgroup>
<col style="width: 10%" />
<col style="width: 9%" />
<col style="width: 9%" />
<col style="width: 10%" />
<col style="width: 8%" />
<col style="width: 8%" />
<col style="width: 8%" />
<col style="width: 9%" />
<col style="width: 7%" />
<col style="width: 8%" />
<col style="width: 8%" />
</colgroup>
<tbody>
<tr class="odd">
<td colspan="11"><h2
id="table-11.-comparison-of-life-cycle-air-emissionspercentage-change-in-average-daily-emissions"><strong>Table
11. Comparison of Life-Cycle Air Emissions—Percentage Change in Average
Daily Emissions</strong></h2>
<p><strong>Due to New Scheduling Algorithm (Wenv = 0.125) Versus
Baseline (Cost-Only Algorithm)</strong></p></td>
</tr>
<tr class="even">
<td><p><u>Fleet Size</u></p>
<p><u>(Tot. Veh.)</u></p></td>
<td><p><u>Avg.</u></p>
<p><u>Cost</u></p></td>
<td><u>VOC)</u></td>
<td><u>Air Toxics</u></td>
<td><u>SOx</u></td>
<td><u>NOx</u></td>
<td><u>CO</u></td>
<td><u>CO2-Equiv.</u></td>
<td><u>CH4</u></td>
<td><u>PM10</u></td>
<td><u>DPM-10</u></td>
</tr>
<tr class="odd">
<td colspan="11">Case I - Heterogeneous Fleet (CV, GV, GB, DB) (n = 10,
1000 requests/day)</td>
</tr>
<tr class="even">
<td>210</td>
<td>4.2</td>
<td>-14.3</td>
<td>-25.4</td>
<td>-3.8</td>
<td>-25.0</td>
<td>2.0</td>
<td>0.4</td>
<td>136.3</td>
<td>3.1</td>
<td>-69.6</td>
</tr>
<tr class="odd">
<td>180</td>
<td>3.3</td>
<td>-7.3</td>
<td>-13.2</td>
<td>-1.9</td>
<td>-13.0</td>
<td>1.3</td>
<td>0.3</td>
<td>46.4</td>
<td>1.6</td>
<td>-39.3</td>
</tr>
<tr class="even">
<td>150</td>
<td>-0.4</td>
<td>-3.4</td>
<td>-6.1</td>
<td>-1.0</td>
<td>-6.0</td>
<td>0.4</td>
<td>-0.1</td>
<td>17.1</td>
<td>0.5</td>
<td>-18.4</td>
</tr>
<tr class="odd">
<td colspan="11">Case II - Heterogeneous Fleet (CV, GB) (n = 10, 1000
requests/day)</td>
</tr>
<tr class="even">
<td>210</td>
<td>2.1</td>
<td>-4.0</td>
<td>-22.4</td>
<td>-6.8</td>
<td>-6.4</td>
<td>-19.2</td>
<td>-8.5</td>
<td>71.2</td>
<td>-6.5</td>
<td></td>
</tr>
<tr class="odd">
<td>180</td>
<td>2.4</td>
<td>-1.9</td>
<td>-11.5</td>
<td>-3.3</td>
<td>-3.1</td>
<td>-9.8</td>
<td>-4.2</td>
<td>29.9</td>
<td>-3.2</td>
<td></td>
</tr>
<tr class="even">
<td>150</td>
<td>2.4</td>
<td>-0.9</td>
<td>-5.1</td>
<td>-1.5</td>
<td>-1.4</td>
<td>-4.4</td>
<td>-1.9</td>
<td>11.6</td>
<td>-1.5</td>
<td></td>
</tr>
<tr class="odd">
<td colspan="11">Case III - Homogeneous Fleet (GB) (n = 10, 1000
requests/day)</td>
</tr>
<tr class="even">
<td>210</td>
<td>1.7</td>
<td>-0.7</td>
<td>-0.7</td>
<td>-0.7</td>
<td>-0.7</td>
<td>-0.7</td>
<td>-0.7</td>
<td>-0.7</td>
<td>-0.7</td>
<td></td>
</tr>
<tr class="odd">
<td>180</td>
<td>2.9</td>
<td>-0.6</td>
<td>-0.5</td>
<td>-0.6</td>
<td>-0.6</td>
<td>-0.5</td>
<td>-0.6</td>
<td>-0.6</td>
<td>-0.6</td>
<td></td>
</tr>
<tr class="even">
<td>150</td>
<td>0.9</td>
<td>0.0</td>
<td>0.0</td>
<td>0.0</td>
<td>0.0</td>
<td>0.0</td>
<td>0.0</td>
<td>-0.1</td>
<td>0.0</td>
<td></td>
</tr>
</tbody>
</table>

[APPENDIX A: VEHICLE LIFE-CYCLE ENVIRONMENTAL IMPACT BASIS]{.underline}

**Life-Cycle Stage Environmental Impacts**

Calculated values of life-cycle environmental impacts, by life-cycle
stage, are provided in Tables A1 through A4 for the vehicle types
considered. The basis for the values is provided in the subsequent
"Notes."

+-----------+-------------------+-----------+-----------+-----------+
| **Table   |                   |           |           |           |
| A1.       |                   |           |           |           |
| Pa        |                   |           |           |           |
| ratransit |                   |           |           |           |
| L         |                   |           |           |           |
| ife-Cycle |                   |           |           |           |
| Inventory |                   |           |           |           |
| Model and |                   |           |           |           |
| Impact    |                   |           |           |           |
| Data      |                   |           |           |           |
| Basis**   |                   |           |           |           |
|           |                   |           |           |           |
| *         |                   |           |           |           |
| *(Vehicle |                   |           |           |           |
| Type:     |                   |           |           |           |
| Gasoline  |                   |           |           |           |
| -Powered, |                   |           |           |           |
| Light     |                   |           |           |           |
| Duty      |                   |           |           |           |
| M         |                   |           |           |           |
| inivan)** |                   |           |           |           |
+-----------+-------------------+-----------+-----------+-----------+
| [L/C      | [Im               | [Running  | [Idle     | [Start    |
| Stage]{.u | pact]{.underline} | (1)]{.u   | (g/       | (g/s      |
| nderline} |                   | nderline} | min.)]{.u | tart)]{.u |
|           |                   |           | nderline} | nderline} |
+-----------+-------------------+-----------+-----------+-----------+
| Vehicle   | [Vehicle          | (g/mile)  | (         | (g/start) |
|           | emissi            |           | g/minute) |           |
| Operation | ons]{.underline}: |           |           |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | NMOG (VOC) (2)    | 0.0535    | 0.2746    | 0.2220    |
+-----------+-------------------+-----------+-----------+-----------+
|           | Methane           | 0.0087    | 0.0526    | 0.0160    |
+-----------+-------------------+-----------+-----------+-----------+
|           | Benzene           | 0.0021    | 0.0123    | 0.0097    |
+-----------+-------------------+-----------+-----------+-----------+
|           | Toluene           | 0.0060    | 0.0352    | 0.0276    |
+-----------+-------------------+-----------+-----------+-----------+
|           | Formaldehyde      | 0.0013    | 0.0088    | 0.0067    |
+-----------+-------------------+-----------+-----------+-----------+
|           | 1,3-Butadiene     | 0.0003    | 0.0018    | 0.0013    |
+-----------+-------------------+-----------+-----------+-----------+
|           | Acetaldehyde      | 0.0003    | 0.0018    | 0.0013    |
+-----------+-------------------+-----------+-----------+-----------+
|           | MTBE              | 0.0042    | 0.0176    | 0.0149    |
+-----------+-------------------+-----------+-----------+-----------+
|           | CO                | 1.61      | 6.19      | 2.92      |
+-----------+-------------------+-----------+-----------+-----------+
|           | NO~x~ (as NO~2~)  | 0.19      | 0.103     | 0.35      |
+-----------+-------------------+-----------+-----------+-----------+
|           | CO~2~             | 427       | 107       | 72.3      |
+-----------+-------------------+-----------+-----------+-----------+
|           | PM-10             | 0.0270    |           |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | SO~2~             | 0.006     |           |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | [Fuel             | (g        | (g        | (ga       |
|           | Consumpt          | al./mile) | al./min.) | l./start) |
|           | ion]{.underline}: |           |           |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | Gasoline          | 0.0498    | 0.0125    | 0.0085    |
+-----------+-------------------+-----------+-----------+-----------+
| Service   | [Fuel             | (g/mile)  | (         | (g/start) |
| and       | ing]{.underline}: |           | g/minute) |           |
|           |                   |           |           |           |
| Ma        |                   |           |           |           |
| intenance |                   |           |           |           |
|           |                   |           |           |           |
| (inc.     |                   |           |           |           |
| fueling)  |                   |           |           |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | NMOG (VOC)        | 0.0100    | 0.0025    | 0.0017    |
|           | emissions         |           |           |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | [EIO-LCA          | Based on  |           |           |
|           | Impa              | vehicle   |           |           |
|           | cts]{.underline}: | mileage   |           |           |
|           | (3)               | only.     |           |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | Non.renew. energy | 0.585     | MJ/mile   |           |
|           | use               |           | (1MJ =    |           |
|           |                   |           | 1E+06 J)  |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | Ozone-depl.       | 0         | kg        |           |
|           | emissions         |           | CF        |           |
|           |                   |           | C-equival |           |
|           |                   |           | ents/mile |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | Global warm.      | 40.0      | g         |           |
|           | emissions         |           | CO~2      |           |
|           |                   |           | ~-equival |           |
|           |                   |           | ents/mile |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | SO~2~ emissions   | 0.134     | g/mile    |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | CO emissions      | 0.174     | g/mile    |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | NO~2~ emissions   | 0.096     | g/mile    |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | VOC emissions     | 0.026     | g/mile    |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | Pb emissions      | 0         | g/mile    |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | PM-10 emissions   | 0.013     | g/mile    |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | TRI air emissions | 0.004     | g/mile    |           |
|           |                   |           | (CMU      |           |
|           |                   |           | Equiv.    |           |
|           |                   |           | Tox.      |           |
|           |                   |           | units)    |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | RCRA wastes       | 0.149     | g/mile    |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | Base-metal ore    | 7.21      | g/mile    |           |
|           | depletion         |           |           |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | Prec. metal ore   | 1.35      | g/mile    |           |
|           | depletion         |           |           |           |
+-----------+-------------------+-----------+-----------+-----------+
| \(1\)     |                   |           |           |           |
| Vehicle   |                   |           |           |           |
| use-phase |                   |           |           |           |
| "running" |                   |           |           |           |
| emissions |                   |           |           |           |
| from      |                   |           |           |           |
| C         |                   |           |           |           |
| alifornia |                   |           |           |           |
| Air       |                   |           |           |           |
| Resources |                   |           |           |           |
| Board     |                   |           |           |           |
| (CARB)    |                   |           |           |           |
|           |                   |           |           |           |
| EMFAC20   |                   |           |           |           |
| 00/Burden |                   |           |           |           |
| emissions |                   |           |           |           |
| model as  |                   |           |           |           |
| well as   |                   |           |           |           |
| from      |                   |           |           |           |
| other     |                   |           |           |           |
| l         |                   |           |           |           |
| iterature |                   |           |           |           |
| sources.  |                   |           |           |           |
|           |                   |           |           |           |
| Emissions |                   |           |           |           |
| based on  |                   |           |           |           |
| CARB's    |                   |           |           |           |
| Unified   |                   |           |           |           |
| C         |                   |           |           |           |
| orrection |                   |           |           |           |
| Cycle to  |                   |           |           |           |
| the FTP   |                   |           |           |           |
| driving   |                   |           |           |           |
| cycle,    |                   |           |           |           |
| which is  |                   |           |           |           |
|           |                   |           |           |           |
| based on  |                   |           |           |           |
| average   |                   |           |           |           |
| driving   |                   |           |           |           |
| speed of  |                   |           |           |           |
| appr      |                   |           |           |           |
| oximately |                   |           |           |           |
| 28 mph    |                   |           |           |           |
| and       |                   |           |           |           |
| includes  |                   |           |           |           |
| appr      |                   |           |           |           |
| oximately |                   |           |           |           |
| 6.5       |                   |           |           |           |
|           |                   |           |           |           |
| st        |                   |           |           |           |
| arts/day. |                   |           |           |           |
| See       |                   |           |           |           |
| "Notes"   |                   |           |           |           |
| for       |                   |           |           |           |
| a         |                   |           |           |           |
| dditional |                   |           |           |           |
| details.  |                   |           |           |           |
|           |                   |           |           |           |
| \(2\)     |                   |           |           |           |
| NMOG      |                   |           |           |           |
| excludes  |                   |           |           |           |
| benzene,  |                   |           |           |           |
| toluene,  |                   |           |           |           |
| form      |                   |           |           |           |
| aldehyde, |                   |           |           |           |
| acet      |                   |           |           |           |
| aldehyde, |                   |           |           |           |
| 1,3-b     |                   |           |           |           |
| utadiene, |                   |           |           |           |
| an MTBE.  |                   |           |           |           |
|           |                   |           |           |           |
| \(3\)     |                   |           |           |           |
| From      |                   |           |           |           |
| Carneg    |                   |           |           |           |
| ie-Mellon |                   |           |           |           |
| EIO-LCA   |                   |           |           |           |
| database  |                   |           |           |           |
| as well   |                   |           |           |           |
| as        |                   |           |           |           |
| l         |                   |           |           |           |
| iterature |                   |           |           |           |
| sources.  |                   |           |           |           |
+-----------+-------------------+-----------+-----------+-----------+

+-----------+-------------------+-----------+-----------+---+-----------+
| **Table   |                   |           |           |   |           |
| A1.       |                   |           |           |   |           |
| Pa        |                   |           |           |   |           |
| ratransit |                   |           |           |   |           |
| L         |                   |           |           |   |           |
| ife-Cycle |                   |           |           |   |           |
| Inventory |                   |           |           |   |           |
| Model and |                   |           |           |   |           |
| Impact    |                   |           |           |   |           |
| Data      |                   |           |           |   |           |
| Basis     |                   |           |           |   |           |
| (cont.)** |                   |           |           |   |           |
|           |                   |           |           |   |           |
| *         |                   |           |           |   |           |
| *(Vehicle |                   |           |           |   |           |
| Type:     |                   |           |           |   |           |
| Gasoline  |                   |           |           |   |           |
| -Powered, |                   |           |           |   |           |
| Light     |                   |           |           |   |           |
| Duty      |                   |           |           |   |           |
| M         |                   |           |           |   |           |
| inivan)** |                   |           |           |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
| [L/C      | [Im               | [Running  | [Idle     | [ |           |
| Stage]{.u | pact]{.underline} | (         | (g/       | S |           |
| nderline} |                   | g/mi)]{.u | min.)]{.u | t |           |
|           |                   | nderline} | nderline} | a |           |
|           |                   |           |           | r |           |
|           |                   |           |           | t |           |
|           |                   |           |           | ( |           |
|           |                   |           |           | g |           |
|           |                   |           |           | / |           |
|           |                   |           |           | s |           |
|           |                   |           |           | t |           |
|           |                   |           |           | a |           |
|           |                   |           |           | r |           |
|           |                   |           |           | t |           |
|           |                   |           |           | ) |           |
|           |                   |           |           | ] |           |
|           |                   |           |           | { |           |
|           |                   |           |           | . |           |
|           |                   |           |           | u |           |
|           |                   |           |           | n |           |
|           |                   |           |           | d |           |
|           |                   |           |           | e |           |
|           |                   |           |           | r |           |
|           |                   |           |           | l |           |
|           |                   |           |           | i |           |
|           |                   |           |           | n |           |
|           |                   |           |           | e |           |
|           |                   |           |           | } |           |
+-----------+-------------------+-----------+-----------+---+-----------+
| Fuel      | [EIO-LCA          | Based on  |           |   |           |
|           | Impa              | fuel      |           |   |           |
| P         | cts]{.underline}: | con       |           |   |           |
| roduction | (3)               | sumption. |           |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | Non-renew. energy | 3.913     | 0.982     |   | 0.668     |
|           | use               | MJ/mile   | MJ/min    |   | MJ/start  |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | Ozone-depl.       | 0         | 0         |   | 0         |
|           | emissions         |           |           |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | Global warm.      | 187.2     | 47.0      |   | 32.0      |
|           | emissions         | (g/mile)  | (g/min.)  |   | (g/min.)  |
|           |                   |           |           |   |           |
|           | (C                |           |           |   |           |
|           | O~2~-equivalents) |           |           |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | SO~2~ emissions   | 0.269     | 0.068     |   | 0.046     |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | CO emissions      | 0.230     | 0.058     |   | 0.039     |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | NO~2~ emissions   | 0.341     | 0.086     |   | 0.058     |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | VOC emissions     | 0.107     | 0.027     |   | 0.018     |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | Pb emissions      | 0         | 0         |   | 0         |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | PM-10 emissions   | 0.035     | 0.009     |   | 0.006     |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | TRI air emissions | 0.002     | ≈ 0       |   | ≈ 0       |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | RCRA wastes       | 0.204     | 0.051     |   | 0.035     |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | Base-metal ore    | 2.072     | 0.520     |   | 0.354     |
|           | depletion         |           |           |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | Prec. metal ore   | 0.304     | 0.076     |   | 0.052     |
|           | depletion         |           |           |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
| Vehicle   | [EIO-LCA          | Based on  |           |   |           |
|           | Impa              | vehicle   |           |   |           |
| P         | cts]{.underline}: | mileage   |           |   |           |
| roduction | (3)               | only.     |           |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | Non-renew. energy | 2.99      | MJ/mile   |   |           |
|           | use               |           |           |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | Ozone-depl.       | 0         | kg        |   |           |
|           | emissions         |           | CF        |   |           |
|           |                   |           | C-equival |   |           |
|           |                   |           | ents/mile |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | Global warm.      | 213       | g         |   |           |
|           | emissions         |           | CO~2      |   |           |
|           |                   |           | ~-equival |   |           |
|           |                   |           | ents/mile |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | SO~2~ emissions   | 0.674     | g/mile    |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | CO emissions      | 1.011     | g/mile    |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | NO~2~ emissions   | 0.461     | g/mile    |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | VOC emissions     | 0.248     | g/mile    |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | Pb emissions      | 0         | g/mile    |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | PM-10 emissions   | 0.073     | g/mile    |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | TRI air emissions | 0.036     | g/mile    |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | RCRA wastes       | 1.113     | g/mile    |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | Base-metal ore    | 57.4      | g/mile    |   |           |
|           | depletion         |           |           |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | Prec. metal ore   | 11.07     | g/mile    |   |           |
|           | depletion         |           |           |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
| Vehicle   | [Non-recov.       | Based on  |           |   |           |
|           | was               | vehicle   |           |   |           |
| Disposal  | tes]{.underline}: | mileage   |           |   |           |
|           | (4)               | only.     |           |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | Landfilled wastes | 4.80      | g/mile    |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
| \(4\)     |                   |           |           |   |           |
| L         |                   |           |           |   |           |
| andfilled |                   |           |           |   |           |
| wastes    |                   |           |           |   |           |
| are the   |                   |           |           |   |           |
| only      |                   |           |           |   |           |
| disposal  |                   |           |           |   |           |
| impact    |                   |           |           |   |           |
| modeled.  |                   |           |           |   |           |
| Over 75%  |                   |           |           |   |           |
| of the    |                   |           |           |   |           |
| mass of   |                   |           |           |   |           |
| the       |                   |           |           |   |           |
|           |                   |           |           |   |           |
| vehicle   |                   |           |           |   |           |
| is        |                   |           |           |   |           |
| assumed   |                   |           |           |   |           |
| to be     |                   |           |           |   |           |
| recycled, |                   |           |           |   |           |
| which     |                   |           |           |   |           |
| consumes  |                   |           |           |   |           |
| energy    |                   |           |           |   |           |
| and       |                   |           |           |   |           |
| materials |                   |           |           |   |           |
| and       |                   |           |           |   |           |
| generates |                   |           |           |   |           |
|           |                   |           |           |   |           |
| material  |                   |           |           |   |           |
| "cr       |                   |           |           |   |           |
| edits"--- |                   |           |           |   |           |
| materials |                   |           |           |   |           |
| returned  |                   |           |           |   |           |
| to the    |                   |           |           |   |           |
| economy.  |                   |           |           |   |           |
| However,  |                   |           |           |   |           |
| di        |                   |           |           |   |           |
| fferences |                   |           |           |   |           |
| among     |                   |           |           |   |           |
|           |                   |           |           |   |           |
| vehicle   |                   |           |           |   |           |
| types and |                   |           |           |   |           |
| routing/s |                   |           |           |   |           |
| cheduling |                   |           |           |   |           |
| alt       |                   |           |           |   |           |
| ernatives |                   |           |           |   |           |
| based on  |                   |           |           |   |           |
| them are  |                   |           |           |   |           |
| assumed   |                   |           |           |   |           |
| ne        |                   |           |           |   |           |
| gligible. |                   |           |           |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+

+-----------+-------------------+-----------+-----------+-----------+
| **Table   |                   |           |           |           |
| A2.       |                   |           |           |           |
| Pa        |                   |           |           |           |
| ratransit |                   |           |           |           |
| L         |                   |           |           |           |
| ife-Cycle |                   |           |           |           |
| Inventory |                   |           |           |           |
| Model and |                   |           |           |           |
| Impact    |                   |           |           |           |
| Data      |                   |           |           |           |
| Basis**   |                   |           |           |           |
|           |                   |           |           |           |
| *         |                   |           |           |           |
| *(Vehicle |                   |           |           |           |
| Type:     |                   |           |           |           |
| Gasoline  |                   |           |           |           |
| -Powered, |                   |           |           |           |
| Medium    |                   |           |           |           |
| Duty      |                   |           |           |           |
| "Shuttle  |                   |           |           |           |
| Bus")**   |                   |           |           |           |
+-----------+-------------------+-----------+-----------+-----------+
| [L/C      | [Im               | [Running  | [Idle     | [Start    |
| Stage]{.u | pact]{.underline} | (1)]{.u   | (g/       | (g/s      |
| nderline} |                   | nderline} | min.)]{.u | tart)]{.u |
|           |                   |           | nderline} | nderline} |
+-----------+-------------------+-----------+-----------+-----------+
| Vehicle   | [Vehicle          | (g/mile)  | (         | (g/start) |
|           | emissi            |           | g/minute) |           |
| Operation | ons]{.underline}: |           |           |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | NMOG (VOC) (2)    | 0.1931    | 0.4665    | 0.5256    |
+-----------+-------------------+-----------+-----------+-----------+
|           | Methane           | 0.0310    | 0.0749    | 0.0370    |
+-----------+-------------------+-----------+-----------+-----------+
|           | Benzene           | 0.0085    | 0.0205    | 0.0237    |
+-----------+-------------------+-----------+-----------+-----------+
|           | Toluene           | 0.0243    | 0.0587    | 0.0674    |
+-----------+-------------------+-----------+-----------+-----------+
|           | Formaldehyde      | 0.0060    | 0.1450    | 0.0168    |
+-----------+-------------------+-----------+-----------+-----------+
|           | 1,3-Butadiene     | 0.0012    | 0.0029    | 0.0034    |
+-----------+-------------------+-----------+-----------+-----------+
|           | Acetaldehyde      | 0.0012    | 0.0029    | 0.0034    |
+-----------+-------------------+-----------+-----------+-----------+
|           | MTBE              | 0.0128    | 0.0309    | 0.0337    |
+-----------+-------------------+-----------+-----------+-----------+
|           | CO                | 4.596     | 12.3      | 9.198     |
+-----------+-------------------+-----------+-----------+-----------+
|           | NO~x~ (as NO~2~)  | 1.007     | 0.170     | 1.314     |
+-----------+-------------------+-----------+-----------+-----------+
|           | CO~2~             | 743.8     | 187.0     | 83.88     |
+-----------+-------------------+-----------+-----------+-----------+
|           | PM-10             | 0.051     |           |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | SO~2~             | 0.011     |           |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | [Fuel             | (g        | (g        | (ga       |
|           | Consumpt          | al./mile) | al./min.) | l./start) |
|           | ion]{.underline}: |           |           |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | Gasoline          | 0.0889    | 0.0223    | 0.0100    |
+-----------+-------------------+-----------+-----------+-----------+
| Service   | [Fuel             | (g/mile)  | (         | (g/start) |
| and       | ing]{.underline}: |           | g/minute) |           |
|           |                   |           |           |           |
| Ma        |                   |           |           |           |
| intenance |                   |           |           |           |
|           |                   |           |           |           |
| (inc.     |                   |           |           |           |
| fueling)  |                   |           |           |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | NMOG (VOC)        | 0.0178    | 0.0044    | 0.0020    |
|           | emissions         |           |           |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | [EIO-LCA          | Based on  |           |           |
|           | Impa              | vehicle   |           |           |
|           | cts]{.underline}: | mileage   |           |           |
|           | (3)               | only.     |           |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | Non.renew. energy | 0.585     | MJ/mile   |           |
|           | use               |           | (1MJ =    |           |
|           |                   |           | 1E+06 J)  |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | Ozone-depl.       | 0         | kg        |           |
|           | emissions         |           | CF        |           |
|           |                   |           | C-equival |           |
|           |                   |           | ents/mile |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | Global warm.      | 40.0      | g         |           |
|           | emissions         |           | CO~2      |           |
|           |                   |           | ~-equival |           |
|           |                   |           | ents/mile |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | SO~2~ emissions   | 0.134     | g/mile    |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | CO emissions      | 0.174     | g/mile    |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | NO~2~ emissions   | 0.096     | g/mile    |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | VOC emissions     | 0.026     | g/mile    |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | Pb emissions      | 0         | g/mile    |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | PM-10 emissions   | 0.013     | g/mile    |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | TRI air emissions | 0.004     | g/mile    |           |
|           |                   |           | (CMU      |           |
|           |                   |           | Equiv.    |           |
|           |                   |           | Tox.      |           |
|           |                   |           | units)    |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | RCRA wastes       | 0.149     | g/mile    |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | Base-metal ore    | 7.21      | g/mile    |           |
|           | depletion         |           |           |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | Prec. metal ore   | 1.35      | g/mile    |           |
|           | depletion         |           |           |           |
+-----------+-------------------+-----------+-----------+-----------+
| \(1\)     |                   |           |           |           |
| Vehicle   |                   |           |           |           |
| use-phase |                   |           |           |           |
| "running" |                   |           |           |           |
| emissions |                   |           |           |           |
| from      |                   |           |           |           |
| C         |                   |           |           |           |
| alifornia |                   |           |           |           |
| Air       |                   |           |           |           |
| Resources |                   |           |           |           |
| Board     |                   |           |           |           |
| (CARB)    |                   |           |           |           |
|           |                   |           |           |           |
| EMFAC20   |                   |           |           |           |
| 00/Burden |                   |           |           |           |
| emissions |                   |           |           |           |
| model as  |                   |           |           |           |
| well as   |                   |           |           |           |
| from      |                   |           |           |           |
| other     |                   |           |           |           |
| l         |                   |           |           |           |
| iterature |                   |           |           |           |
| sources.  |                   |           |           |           |
|           |                   |           |           |           |
| Emissions |                   |           |           |           |
| based on  |                   |           |           |           |
| CARB's    |                   |           |           |           |
| Unified   |                   |           |           |           |
| C         |                   |           |           |           |
| orrection |                   |           |           |           |
| Cycle to  |                   |           |           |           |
| the FTP   |                   |           |           |           |
| driving   |                   |           |           |           |
| cycle,    |                   |           |           |           |
| which is  |                   |           |           |           |
|           |                   |           |           |           |
| based on  |                   |           |           |           |
| average   |                   |           |           |           |
| driving   |                   |           |           |           |
| speed of  |                   |           |           |           |
| appr      |                   |           |           |           |
| oximately |                   |           |           |           |
| 28 mph    |                   |           |           |           |
| and       |                   |           |           |           |
| includes  |                   |           |           |           |
| appr      |                   |           |           |           |
| oximately |                   |           |           |           |
| 6.5       |                   |           |           |           |
|           |                   |           |           |           |
| st        |                   |           |           |           |
| arts/day. |                   |           |           |           |
| See       |                   |           |           |           |
| "Notes"   |                   |           |           |           |
| for       |                   |           |           |           |
| a         |                   |           |           |           |
| dditional |                   |           |           |           |
| details.  |                   |           |           |           |
|           |                   |           |           |           |
| \(2\)     |                   |           |           |           |
| NMOG      |                   |           |           |           |
| excludes  |                   |           |           |           |
| benzene,  |                   |           |           |           |
| toluene,  |                   |           |           |           |
| form      |                   |           |           |           |
| aldehyde, |                   |           |           |           |
| acet      |                   |           |           |           |
| aldehyde, |                   |           |           |           |
| 1,3-b     |                   |           |           |           |
| utadiene, |                   |           |           |           |
| an MTBE.  |                   |           |           |           |
|           |                   |           |           |           |
| \(3\)     |                   |           |           |           |
| From      |                   |           |           |           |
| Carneg    |                   |           |           |           |
| ie-Mellon |                   |           |           |           |
| EIO-LCA   |                   |           |           |           |
| database  |                   |           |           |           |
| as well   |                   |           |           |           |
| as        |                   |           |           |           |
| l         |                   |           |           |           |
| iterature |                   |           |           |           |
| sources.  |                   |           |           |           |
+-----------+-------------------+-----------+-----------+-----------+

+-----------+-------------------+-----------+-----------+---+-----------+
| **Table   |                   |           |           |   |           |
| A2.       |                   |           |           |   |           |
| Pa        |                   |           |           |   |           |
| ratransit |                   |           |           |   |           |
| L         |                   |           |           |   |           |
| ife-Cycle |                   |           |           |   |           |
| Inventory |                   |           |           |   |           |
| Model and |                   |           |           |   |           |
| Impact    |                   |           |           |   |           |
| Data      |                   |           |           |   |           |
| Basis     |                   |           |           |   |           |
| (cont.)** |                   |           |           |   |           |
|           |                   |           |           |   |           |
| *         |                   |           |           |   |           |
| *(Vehicle |                   |           |           |   |           |
| Type:     |                   |           |           |   |           |
| Gasoline  |                   |           |           |   |           |
| -Powered, |                   |           |           |   |           |
| Medium    |                   |           |           |   |           |
| Duty      |                   |           |           |   |           |
| "Shuttle  |                   |           |           |   |           |
| Bus")**   |                   |           |           |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
| [L/C      | [Im               | [Running  | [Idle     | [ |           |
| Stage]{.u | pact]{.underline} | (g        | (g/       | S |           |
| nderline} |                   | /mi.)]{.u | min.)]{.u | t |           |
|           |                   | nderline} | nderline} | a |           |
|           |                   |           |           | r |           |
|           |                   |           |           | t |           |
|           |                   |           |           | ( |           |
|           |                   |           |           | g |           |
|           |                   |           |           | / |           |
|           |                   |           |           | s |           |
|           |                   |           |           | t |           |
|           |                   |           |           | a |           |
|           |                   |           |           | r |           |
|           |                   |           |           | t |           |
|           |                   |           |           | ) |           |
|           |                   |           |           | ] |           |
|           |                   |           |           | { |           |
|           |                   |           |           | . |           |
|           |                   |           |           | u |           |
|           |                   |           |           | n |           |
|           |                   |           |           | d |           |
|           |                   |           |           | e |           |
|           |                   |           |           | r |           |
|           |                   |           |           | l |           |
|           |                   |           |           | i |           |
|           |                   |           |           | n |           |
|           |                   |           |           | e |           |
|           |                   |           |           | } |           |
+-----------+-------------------+-----------+-----------+---+-----------+
| Fuel      | [EIO-LCA          | Based on  |           |   |           |
|           | Impa              | fuel      |           |   |           |
| P         | cts]{.underline}: | con       |           |   |           |
| roduction | (3)               | sumption. |           |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | Non-renew. energy | 9.99      | 1.76      |   | 0.786     |
|           | use               | MJ/mile   | MJ/min.   |   | MJ/start  |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | Ozone-depl.       | 0         | 0         |   | 0         |
|           | emissions         |           |           |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | Global warm.      | 335.5     | 84.3      |   | 37.7      |
|           | emissions         |           |           |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | SO~2~ emissions   | 0.481     | 0.121     |   | 0.054     |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | CO emissions      | 0.411     | 0.103     |   | 0.046     |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | NO~2~ emissions   | 0.611     | 0.153     |   | 0.069     |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | VOC emissions     | 0.192     | 0.048     |   | 0.021     |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | Pb emissions      | 0         | 0         |   | 0         |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | PM-10 emissions   | 0.062     | 0.016     |   | 0.007     |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | TRI air emissions | 0.003     | 0.001     |   | ≈ 0       |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | RCRA wastes       | 0.365     | 0.092     |   | 0.041     |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | Base-metal ore    | 3.699     | 0.929     |   | 0.415     |
|           | depletion         |           |           |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | Prec. metal ore   | 0.545     | 0.137     |   | 0.061     |
|           | depletion         |           |           |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
| Vehicle   | [EIO-LCA          | Based on  |           |   |           |
|           | Impa              | vehicle   |           |   |           |
| P         | cts]{.underline}: | mileage   |           |   |           |
| roduction | (3)               | only.     |           |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | Non-renew. energy | 2.56      | MJ/mile   |   |           |
|           | use               |           |           |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | Ozone-depl.       | 0         | kg        |   |           |
|           | emissions         |           | CF        |   |           |
|           |                   |           | C-equival |   |           |
|           |                   |           | ents/mile |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | Global warm.      | 182.8     | g         |   |           |
|           | emissions         |           | CO~2      |   |           |
|           |                   |           | ~-equival |   |           |
|           |                   |           | ents/mile |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | SO~2~ emissions   | 0.577     | g/mile    |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | CO emissions      | 0.867     | g/mile    |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | NO~2~ emissions   | 0.462     | g/mile    |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | VOC emissions     | 0.213     | g/mile    |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | Pb emissions      | 0         | g/mile    |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | PM-10 emissions   | 0.062     | g/mile    |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | TRI air emissions | 0.031     | g/mile    |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | RCRA wastes       | 0.954     | g/mile    |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | Base-metal ore    | 49.21     | g/mile    |   |           |
|           | depletion         |           |           |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | Prec. metal ore   | 9.49      | g/mile    |   |           |
|           | depletion         |           |           |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
| Vehicle   | [Non-recov.       | Based on  |           |   |           |
|           | was               | vehicle   |           |   |           |
| Disposal  | tes]{.underline}: | mileage   |           |   |           |
|           | (4)               | only.     |           |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | Landfilled wastes | 5.19      | g/mile    |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
| \(4\)     |                   |           |           |   |           |
| L         |                   |           |           |   |           |
| andfilled |                   |           |           |   |           |
| wastes    |                   |           |           |   |           |
| are the   |                   |           |           |   |           |
| only      |                   |           |           |   |           |
| disposal  |                   |           |           |   |           |
| impact    |                   |           |           |   |           |
| modeled.  |                   |           |           |   |           |
| Over 75%  |                   |           |           |   |           |
| of the    |                   |           |           |   |           |
| mass of   |                   |           |           |   |           |
| the       |                   |           |           |   |           |
|           |                   |           |           |   |           |
| vehicle   |                   |           |           |   |           |
| is        |                   |           |           |   |           |
| assumed   |                   |           |           |   |           |
| to be     |                   |           |           |   |           |
| recycled, |                   |           |           |   |           |
| which     |                   |           |           |   |           |
| consumes  |                   |           |           |   |           |
| energy    |                   |           |           |   |           |
| and       |                   |           |           |   |           |
| materials |                   |           |           |   |           |
| and       |                   |           |           |   |           |
| generates |                   |           |           |   |           |
|           |                   |           |           |   |           |
| material  |                   |           |           |   |           |
| "cr       |                   |           |           |   |           |
| edits"--- |                   |           |           |   |           |
| materials |                   |           |           |   |           |
| returned  |                   |           |           |   |           |
| to the    |                   |           |           |   |           |
| economy.  |                   |           |           |   |           |
| However,  |                   |           |           |   |           |
| di        |                   |           |           |   |           |
| fferences |                   |           |           |   |           |
| among     |                   |           |           |   |           |
|           |                   |           |           |   |           |
| vehicle   |                   |           |           |   |           |
| types and |                   |           |           |   |           |
| routing/s |                   |           |           |   |           |
| cheduling |                   |           |           |   |           |
| alt       |                   |           |           |   |           |
| ernatives |                   |           |           |   |           |
| based on  |                   |           |           |   |           |
| them are  |                   |           |           |   |           |
| assumed   |                   |           |           |   |           |
| ne        |                   |           |           |   |           |
| gligible. |                   |           |           |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+

+-----------+-------------------+-----------+-----------+-----------+
| **Table   |                   |           |           |           |
| A3.       |                   |           |           |           |
| Pa        |                   |           |           |           |
| ratransit |                   |           |           |           |
| L         |                   |           |           |           |
| ife-Cycle |                   |           |           |           |
| Inventory |                   |           |           |           |
| Model and |                   |           |           |           |
| Impact    |                   |           |           |           |
| Data      |                   |           |           |           |
| Basis**   |                   |           |           |           |
|           |                   |           |           |           |
| *         |                   |           |           |           |
| *(Vehicle |                   |           |           |           |
| Type:     |                   |           |           |           |
| CNG       |                   |           |           |           |
| -Powered, |                   |           |           |           |
| L         |                   |           |           |           |
| ight-Duty |                   |           |           |           |
| M         |                   |           |           |           |
| inivan)** |                   |           |           |           |
+-----------+-------------------+-----------+-----------+-----------+
| [L/C      | [Im               | [Running  | [Idle     | [Start    |
| Stage]{.u | pact]{.underline} | (1)]{.u   | (g/       | (g/s      |
| nderline} |                   | nderline} | min.)]{.u | tart)]{.u |
|           |                   |           | nderline} | nderline} |
+-----------+-------------------+-----------+-----------+-----------+
| Vehicle   | [Vehicle          | (g/mile)  | (         | (g/start) |
|           | emissi            |           | g/minute) |           |
| Operation | ons]{.underline}: |           |           |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | NMOG (VOC) (2)    | 0.18      | 0.012     | 0.0082    |
+-----------+-------------------+-----------+-----------+-----------+
|           | Methane           | 6.50      | 0.358     | 0.245     |
+-----------+-------------------+-----------+-----------+-----------+
|           | Benzene           |           |           |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | Toluene           |           |           |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | Formaldehyde      | 0.018     | 0.0099    | 0.0068    |
+-----------+-------------------+-----------+-----------+-----------+
|           | 1,3-Butadiene     |           |           |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | Acetaldehyde      | 0.002     | 0.0001    | 0.0001    |
+-----------+-------------------+-----------+-----------+-----------+
|           | MTBE              |           |           |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | CO                | 1.20      | 0.032     | 0.0219    |
+-----------+-------------------+-----------+-----------+-----------+
|           | NO~x~ (as NO~2~)  | 0.75      | 0.139     | 0.0952    |
+-----------+-------------------+-----------+-----------+-----------+
|           | CO~2~             | 510       | 29        | 19.9      |
+-----------+-------------------+-----------+-----------+-----------+
|           | PM-10             | 0.0256    | 0.022     | 0.0151    |
+-----------+-------------------+-----------+-----------+-----------+
|           | SO~2~             |           |           |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | [Fuel             | (g        | (g        | (ga       |
|           | Consumpt          | al./mile) | al./min.) | l./start) |
|           | ion]{.underline}: |           |           |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | CNG (in gallons)  | 0.2       | 0.0044    | 0.0030    |
+-----------+-------------------+-----------+-----------+-----------+
| Service   | [Fuel             | (g/mile)  | (         | (g/start) |
| and       | ing]{.underline}: |           | g/minute) |           |
|           |                   |           |           |           |
| Ma        |                   |           |           |           |
| intenance |                   |           |           |           |
|           |                   |           |           |           |
| (inc.     |                   |           |           |           |
| fueling)  |                   |           |           |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | CNG emissions (as | 0.04      | 0.0009    | 0.0006    |
|           | CH~4~)            |           |           |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | [EIO-LCA          | Based on  |           |           |
|           | Impa              | vehicle   |           |           |
|           | cts]{.underline}: | mileage   |           |           |
|           | (3)               | only.     |           |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | Non.renew. energy | 0.724     | MJ/mile   |           |
|           | use               |           | (1MJ =    |           |
|           |                   |           | 1E+06 J)  |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | Ozone-depl.       | 0         | kg        |           |
|           | emissions         |           | CF        |           |
|           |                   |           | C-equival |           |
|           |                   |           | ents/mile |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | Global warm.      | 50        | g         |           |
|           | emissions         |           | CO~2      |           |
|           |                   |           | ~-equival |           |
|           |                   |           | ents/mile |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | SO~2~ emissions   | 0.266     | g/mile    |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | CO emissions      | 0.215     | g/mile    |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | NO~2~ emissions   | 0.119     | g/mile    |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | VOC emissions     | 0.032     | g/mile    |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | Pb emissions      | 0         | g/mile    |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | PM-10 emissions   | 0.016     | g/mile    |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | TRI air emissions | 0.005     | g/mile    |           |
|           |                   |           | (CMU      |           |
|           |                   |           | Equiv.    |           |
|           |                   |           | Tox.      |           |
|           |                   |           | units)    |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | RCRA wastes       | 0.184     | g/mile    |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | Base-metal ore    | 8.93      | g/mile    |           |
|           | depletion         |           |           |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | Prec. metal ore   | 1.67      | g/mile    |           |
|           | depletion         |           |           |           |
+-----------+-------------------+-----------+-----------+-----------+
| \(1\)     |                   |           |           |           |
| Vehicle   |                   |           |           |           |
| use-phase |                   |           |           |           |
| "running" |                   |           |           |           |
| emissions |                   |           |           |           |
| from      |                   |           |           |           |
| C         |                   |           |           |           |
| alifornia |                   |           |           |           |
| Air       |                   |           |           |           |
| Resources |                   |           |           |           |
| Board     |                   |           |           |           |
| (CARB)    |                   |           |           |           |
|           |                   |           |           |           |
| EMFAC20   |                   |           |           |           |
| 00/Burden |                   |           |           |           |
| emissions |                   |           |           |           |
| model as  |                   |           |           |           |
| well as   |                   |           |           |           |
| from      |                   |           |           |           |
| other     |                   |           |           |           |
| l         |                   |           |           |           |
| iterature |                   |           |           |           |
| sources.  |                   |           |           |           |
|           |                   |           |           |           |
| Emissions |                   |           |           |           |
| based on  |                   |           |           |           |
| CARB's    |                   |           |           |           |
| Unified   |                   |           |           |           |
| C         |                   |           |           |           |
| orrection |                   |           |           |           |
| Cycle to  |                   |           |           |           |
| the FTP   |                   |           |           |           |
| driving   |                   |           |           |           |
| cycle,    |                   |           |           |           |
| which is  |                   |           |           |           |
|           |                   |           |           |           |
| based on  |                   |           |           |           |
| average   |                   |           |           |           |
| driving   |                   |           |           |           |
| speed of  |                   |           |           |           |
| appr      |                   |           |           |           |
| oximately |                   |           |           |           |
| 28 mph    |                   |           |           |           |
| and       |                   |           |           |           |
| includes  |                   |           |           |           |
| appr      |                   |           |           |           |
| oximately |                   |           |           |           |
| 6.5       |                   |           |           |           |
|           |                   |           |           |           |
| st        |                   |           |           |           |
| arts/day. |                   |           |           |           |
| See       |                   |           |           |           |
| "Notes"   |                   |           |           |           |
| for       |                   |           |           |           |
| a         |                   |           |           |           |
| dditional |                   |           |           |           |
| details.  |                   |           |           |           |
|           |                   |           |           |           |
| \(2\)     |                   |           |           |           |
| NMOG      |                   |           |           |           |
| excludes  |                   |           |           |           |
| benzene,  |                   |           |           |           |
| toluene,  |                   |           |           |           |
| form      |                   |           |           |           |
| aldehyde, |                   |           |           |           |
| acet      |                   |           |           |           |
| aldehyde, |                   |           |           |           |
| 1,3-b     |                   |           |           |           |
| utadiene, |                   |           |           |           |
| an MTBE.  |                   |           |           |           |
|           |                   |           |           |           |
| \(3\)     |                   |           |           |           |
| From      |                   |           |           |           |
| Carneg    |                   |           |           |           |
| ie-Mellon |                   |           |           |           |
| EIO-LCA   |                   |           |           |           |
| database  |                   |           |           |           |
| as well   |                   |           |           |           |
| as        |                   |           |           |           |
| l         |                   |           |           |           |
| iterature |                   |           |           |           |
| sources.  |                   |           |           |           |
+-----------+-------------------+-----------+-----------+-----------+

+-----------+-------------------+-----------+-----------+---+-----------+
| **Table   |                   |           |           |   |           |
| A3.       |                   |           |           |   |           |
| Pa        |                   |           |           |   |           |
| ratransit |                   |           |           |   |           |
| L         |                   |           |           |   |           |
| ife-Cycle |                   |           |           |   |           |
| Inventory |                   |           |           |   |           |
| Model and |                   |           |           |   |           |
| Impact    |                   |           |           |   |           |
| Data      |                   |           |           |   |           |
| Basis     |                   |           |           |   |           |
| (cont.)** |                   |           |           |   |           |
|           |                   |           |           |   |           |
| *         |                   |           |           |   |           |
| *(Vehicle |                   |           |           |   |           |
| Type:     |                   |           |           |   |           |
| CNG       |                   |           |           |   |           |
| -Powered, |                   |           |           |   |           |
| L         |                   |           |           |   |           |
| ight-Duty |                   |           |           |   |           |
| M         |                   |           |           |   |           |
| inivan)** |                   |           |           |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
| [L/C      | [Im               | [Running  | [Idle     | [ |           |
| Stage]{.u | pact]{.underline} | (g        | (g/       | S |           |
| nderline} |                   | /mi.)]{.u | min.)]{.u | t |           |
|           |                   | nderline} | nderline} | a |           |
|           |                   |           |           | r |           |
|           |                   |           |           | t |           |
|           |                   |           |           | ( |           |
|           |                   |           |           | g |           |
|           |                   |           |           | / |           |
|           |                   |           |           | s |           |
|           |                   |           |           | t |           |
|           |                   |           |           | a |           |
|           |                   |           |           | r |           |
|           |                   |           |           | t |           |
|           |                   |           |           | ) |           |
|           |                   |           |           | ] |           |
|           |                   |           |           | { |           |
|           |                   |           |           | . |           |
|           |                   |           |           | u |           |
|           |                   |           |           | n |           |
|           |                   |           |           | d |           |
|           |                   |           |           | e |           |
|           |                   |           |           | r |           |
|           |                   |           |           | l |           |
|           |                   |           |           | i |           |
|           |                   |           |           | n |           |
|           |                   |           |           | e |           |
|           |                   |           |           | } |           |
+-----------+-------------------+-----------+-----------+---+-----------+
| Fuel      | [EIO-LCA          | Based on  |           |   |           |
|           | Impa              | fuel      |           |   |           |
| P         | cts]{.underline}: | con       |           |   |           |
| roduction | (3)               | sumption. |           |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | Non-renew. energy | 3.14      | 0.069     |   | 0.047     |
|           | use               | MJ/mile   | MJ/min.   |   | MJ/start  |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | Ozone-depl.       | 0         | 0         |   | 0         |
|           | emissions         |           |           |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | Global warm.      | 150.7     | 3.3       |   | 2.3       |
|           | emissions         |           |           |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | SO~2~ emissions   | 0.216     | 0.005     |   | 0.003     |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | CO emissions      | 0.185     | 0.004     |   | 0.003     |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | NO~2~ emissions   | 0.275     | 0.006     |   | 0.004     |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | VOC emissions     | 0.086     | 0.002     |   | 0.001     |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | Pb emissions      | 0         | 0         |   | 0         |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | PM-10 emissions   | 0.028     | 0.001     |   | ≈ 0       |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | TRI air emissions | 0.001     | ≈ 0       |   | ≈ 0       |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | RCRA wastes       | 0.164     | 0.004     |   | 0.002     |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | Base-metal ore    | 1.66      | 0.037     |   | 0.025     |
|           | depletion         |           |           |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | Prec. metal ore   | 0.245     | 0.005     |   | 0.004     |
|           | depletion         |           |           |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
| Vehicle   | [EIO-LCA          | Based on  |           |   |           |
|           | Impa              | vehicle   |           |   |           |
| P         | cts]{.underline}: | mileage   |           |   |           |
| roduction | (3)               | only.     |           |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | Non-renew. energy | 3.16      | MJ/mile   |   |           |
|           | use               |           |           |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | Ozone-depl.       | 0         | kg        |   |           |
|           | emissions         |           | CF        |   |           |
|           |                   |           | C-equival |   |           |
|           |                   |           | ents/mile |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | Global warm.      | 225.5     | g         |   |           |
|           | emissions         |           | CO~2      |   |           |
|           |                   |           | ~-equival |   |           |
|           |                   |           | ents/mile |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | SO~2~ emissions   | 0.712     | g/mile    |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | CO emissions      | 1.069     | g/mile    |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | NO~2~ emissions   | 0.570     | g/mile    |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | VOC emissions     | 0.262     | g/mile    |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | Pb emissions      | 0         | g/mile    |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | PM-10 emissions   | 0.077     | g/mile    |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | TRI air emissions | 0.038     | g/mile    |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | RCRA wastes       | 1.177     | g/mile    |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | Base-metal ore    | 60.69     | g/mile    |   |           |
|           | depletion         |           |           |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | Prec. metal ore   | 11.70     | g/mile    |   |           |
|           | depletion         |           |           |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
| Vehicle   | [Non-recov.       | Based on  |           |   |           |
|           | was               | vehicle   |           |   |           |
| Disposal  | tes]{.underline}: | mileage   |           |   |           |
|           | (4)               | only.     |           |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | Landfilled wastes | 5.55      | g/mile    |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
| \(4\)     |                   |           |           |   |           |
| L         |                   |           |           |   |           |
| andfilled |                   |           |           |   |           |
| wastes    |                   |           |           |   |           |
| are the   |                   |           |           |   |           |
| only      |                   |           |           |   |           |
| disposal  |                   |           |           |   |           |
| impact    |                   |           |           |   |           |
| modeled.  |                   |           |           |   |           |
| Over 75%  |                   |           |           |   |           |
| of the    |                   |           |           |   |           |
| mass of   |                   |           |           |   |           |
| the       |                   |           |           |   |           |
|           |                   |           |           |   |           |
| vehicle   |                   |           |           |   |           |
| is        |                   |           |           |   |           |
| assumed   |                   |           |           |   |           |
| to be     |                   |           |           |   |           |
| recycled, |                   |           |           |   |           |
| which     |                   |           |           |   |           |
| consumes  |                   |           |           |   |           |
| energy    |                   |           |           |   |           |
| and       |                   |           |           |   |           |
| materials |                   |           |           |   |           |
| and       |                   |           |           |   |           |
| generates |                   |           |           |   |           |
|           |                   |           |           |   |           |
| material  |                   |           |           |   |           |
| "cr       |                   |           |           |   |           |
| edits"--- |                   |           |           |   |           |
| materials |                   |           |           |   |           |
| returned  |                   |           |           |   |           |
| to the    |                   |           |           |   |           |
| economy.  |                   |           |           |   |           |
| However,  |                   |           |           |   |           |
| di        |                   |           |           |   |           |
| fferences |                   |           |           |   |           |
| among     |                   |           |           |   |           |
|           |                   |           |           |   |           |
| vehicle   |                   |           |           |   |           |
| types and |                   |           |           |   |           |
| routing/s |                   |           |           |   |           |
| cheduling |                   |           |           |   |           |
| alt       |                   |           |           |   |           |
| ernatives |                   |           |           |   |           |
| based on  |                   |           |           |   |           |
| them are  |                   |           |           |   |           |
| assumed   |                   |           |           |   |           |
| ne        |                   |           |           |   |           |
| gligible. |                   |           |           |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+

+-----------+-------------------+-----------+-----------+-----------+
| **Table   |                   |           |           |           |
| A4.       |                   |           |           |           |
| Pa        |                   |           |           |           |
| ratransit |                   |           |           |           |
| L         |                   |           |           |           |
| ife-Cycle |                   |           |           |           |
| Inventory |                   |           |           |           |
| Model and |                   |           |           |           |
| Impact    |                   |           |           |           |
| Data      |                   |           |           |           |
| Basis**   |                   |           |           |           |
|           |                   |           |           |           |
| *         |                   |           |           |           |
| *(Vehicle |                   |           |           |           |
| Type:     |                   |           |           |           |
| Diesel    |                   |           |           |           |
| -Powered, |                   |           |           |           |
| \[Large\] |                   |           |           |           |
| Medium    |                   |           |           |           |
| Duty      |                   |           |           |           |
| "Shuttle  |                   |           |           |           |
| Bus")**   |                   |           |           |           |
+-----------+-------------------+-----------+-----------+-----------+
| [L/C      | [Im               | [Running  | [Idle     | [Start    |
| Stage]{.u | pact]{.underline} | (1)]{.u   | (g/       | (g/s      |
| nderline} |                   | nderline} | min.)]{.u | tart)]{.u |
|           |                   |           | nderline} | nderline} |
+-----------+-------------------+-----------+-----------+-----------+
| Vehicle   | [Vehicle          | (g/mile)  | (         | (g/start) |
|           | emissi            |           | g/minute) |           |
| Operation | ons]{.underline}: |           |           |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | NMOG (VOC) (2)    | 0.3443    | 0.1062    | 0.0721    |
+-----------+-------------------+-----------+-----------+-----------+
|           | Methane           | 0.0176    | 0.0054    | 0.0037    |
+-----------+-------------------+-----------+-----------+-----------+
|           | Benzene           | 0.0021    | 0.0006    | 0.0004    |
+-----------+-------------------+-----------+-----------+-----------+
|           | Toluene           | 0.0041    | 0.0013    | 0.0009    |
+-----------+-------------------+-----------+-----------+-----------+
|           | Formaldehyde      | 0.0519    | 0.0160    | 0.0109    |
+-----------+-------------------+-----------+-----------+-----------+
|           | 1,3-Butadiene     | 0.0021    | 0.0006    | 0.0004    |
+-----------+-------------------+-----------+-----------+-----------+
|           | Acetaldehyde      | 0.0104    | 0.0032    | 0.0022    |
+-----------+-------------------+-----------+-----------+-----------+
|           | SO~2~             | 0.0360    | 0.0111    | 0.0075    |
+-----------+-------------------+-----------+-----------+-----------+
|           | CO                | 0.6366    | 0.2695    | 0.1829    |
+-----------+-------------------+-----------+-----------+-----------+
|           | NO~x~ (as NO~2~)  | 3.6632    | 0.2675    | 0.1816    |
+-----------+-------------------+-----------+-----------+-----------+
|           | CO~2~             | 444       | 23.6      | 16.0      |
+-----------+-------------------+-----------+-----------+-----------+
|           | PM-10             | 0.0240    |           |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | DPM-10            | 0.0601    | 0.0230    | 0.0156    |
+-----------+-------------------+-----------+-----------+-----------+
|           | [Fuel             | (g        | (g        | (ga       |
|           | Consumpt          | al./mile) | al./min.) | l./start) |
|           | ion]{.underline}: |           |           |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | Diesel            | 0.0444    | 0.0137    | 0.0093    |
+-----------+-------------------+-----------+-----------+-----------+
| Service   | [Fuel             | (g/mile)  | (         | (g/start) |
| and       | ing]{.underline}: |           | g/minute) |           |
|           |                   |           |           |           |
| Ma        |                   |           |           |           |
| intenance |                   |           |           |           |
|           |                   |           |           |           |
| (inc.     |                   |           |           |           |
| fueling)  |                   |           |           |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | NMOG (VOC)        | 0.0089    | 0.0028    | 0.0019    |
|           | emissions         |           |           |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | [EIO-LCA          | Based on  |           |           |
|           | Impa              | vehicle   |           |           |
|           | cts]{.underline}: | mileage   |           |           |
|           | (3)               | only.     |           |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | Non.renew. energy | 0.668     | MJ/mile   |           |
|           | use               |           | (1MJ =    |           |
|           |                   |           | 1E+06 J)  |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | Ozone-depl.       | 0         | kg        |           |
|           | emissions         |           | CF        |           |
|           |                   |           | C-equival |           |
|           |                   |           | ents/mile |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | Global warm.      | 46.2      | g         |           |
|           | emissions         |           | CO~2      |           |
|           |                   |           | ~-equival |           |
|           |                   |           | ents/mile |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | SO~2~ emissions   | 0.153     | g/mile    |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | CO emissions      | 0.199     | g/mile    |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | NO~2~ emissions   | 0.110     | g/mile    |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | VOC emissions     | 0.299     | g/mile    |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | Pb emissions      | 0         | g/mile    |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | PM-10 emissions   | 0.015     | g/mile    |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | TRI air emissions | 0.005     | g/mile    |           |
|           |                   |           | (CMU      |           |
|           |                   |           | Equiv.    |           |
|           |                   |           | Tox.      |           |
|           |                   |           | units)    |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | RCRA wastes       | 0.170     | g/mile    |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | Base-metal ore    | 8.24      | g/mile    |           |
|           | depletion         |           |           |           |
+-----------+-------------------+-----------+-----------+-----------+
|           | Prec. metal ore   | 1.54      | g/mile    |           |
|           | depletion         |           |           |           |
+-----------+-------------------+-----------+-----------+-----------+
| \(1\)     |                   |           |           |           |
| Vehicle   |                   |           |           |           |
| use-phase |                   |           |           |           |
| "running" |                   |           |           |           |
| emissions |                   |           |           |           |
| from      |                   |           |           |           |
| C         |                   |           |           |           |
| alifornia |                   |           |           |           |
| Air       |                   |           |           |           |
| Resources |                   |           |           |           |
| Board     |                   |           |           |           |
| (CARB)    |                   |           |           |           |
|           |                   |           |           |           |
| EMFAC20   |                   |           |           |           |
| 00/Burden |                   |           |           |           |
| emissions |                   |           |           |           |
| model as  |                   |           |           |           |
| well as   |                   |           |           |           |
| from      |                   |           |           |           |
| other     |                   |           |           |           |
| l         |                   |           |           |           |
| iterature |                   |           |           |           |
| sources.  |                   |           |           |           |
|           |                   |           |           |           |
| Emissions |                   |           |           |           |
| based on  |                   |           |           |           |
| CARB's    |                   |           |           |           |
| Unified   |                   |           |           |           |
| C         |                   |           |           |           |
| orrection |                   |           |           |           |
| Cycle to  |                   |           |           |           |
| the FTP   |                   |           |           |           |
| driving   |                   |           |           |           |
| cycle,    |                   |           |           |           |
| which is  |                   |           |           |           |
|           |                   |           |           |           |
| based on  |                   |           |           |           |
| average   |                   |           |           |           |
| driving   |                   |           |           |           |
| speed of  |                   |           |           |           |
| appr      |                   |           |           |           |
| oximately |                   |           |           |           |
| 28 mph    |                   |           |           |           |
| and       |                   |           |           |           |
| includes  |                   |           |           |           |
| appr      |                   |           |           |           |
| oximately |                   |           |           |           |
| 6.5       |                   |           |           |           |
|           |                   |           |           |           |
| st        |                   |           |           |           |
| arts/day. |                   |           |           |           |
| See       |                   |           |           |           |
| "Notes"   |                   |           |           |           |
| for       |                   |           |           |           |
| a         |                   |           |           |           |
| dditional |                   |           |           |           |
| details.  |                   |           |           |           |
|           |                   |           |           |           |
| \(2\)     |                   |           |           |           |
| NMOG      |                   |           |           |           |
| excludes  |                   |           |           |           |
| benzene,  |                   |           |           |           |
| toluene,  |                   |           |           |           |
| form      |                   |           |           |           |
| aldehyde, |                   |           |           |           |
| acet      |                   |           |           |           |
| aldehyde, |                   |           |           |           |
| 1,3-b     |                   |           |           |           |
| utadiene, |                   |           |           |           |
| an MTBE.  |                   |           |           |           |
|           |                   |           |           |           |
| \(3\)     |                   |           |           |           |
| From      |                   |           |           |           |
| Carneg    |                   |           |           |           |
| ie-Mellon |                   |           |           |           |
| EIO-LCA   |                   |           |           |           |
| database  |                   |           |           |           |
| as well   |                   |           |           |           |
| as        |                   |           |           |           |
| l         |                   |           |           |           |
| iterature |                   |           |           |           |
| sources.  |                   |           |           |           |
+-----------+-------------------+-----------+-----------+-----------+

+-----------+-------------------+-----------+-----------+---+-----------+
| **Table   |                   |           |           |   |           |
| A4.       |                   |           |           |   |           |
| Pa        |                   |           |           |   |           |
| ratransit |                   |           |           |   |           |
| L         |                   |           |           |   |           |
| ife-Cycle |                   |           |           |   |           |
| Inventory |                   |           |           |   |           |
| Model and |                   |           |           |   |           |
| Impact    |                   |           |           |   |           |
| Data      |                   |           |           |   |           |
| Basis     |                   |           |           |   |           |
| (cont.)** |                   |           |           |   |           |
|           |                   |           |           |   |           |
| *         |                   |           |           |   |           |
| *(Vehicle |                   |           |           |   |           |
| Type:     |                   |           |           |   |           |
| Diesel    |                   |           |           |   |           |
| -Powered, |                   |           |           |   |           |
| \[Large}  |                   |           |           |   |           |
| Medium    |                   |           |           |   |           |
| Duty      |                   |           |           |   |           |
| "Shuttle  |                   |           |           |   |           |
| Bus")**   |                   |           |           |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
| [L/C      | [Im               | [Running  | [Idle     | [ |           |
| Stage]{.u | pact]{.underline} | (g        | (g/       | S |           |
| nderline} |                   | /mi.)]{.u | min.)]{.u | t |           |
|           |                   | nderline} | nderline} | a |           |
|           |                   |           |           | r |           |
|           |                   |           |           | t |           |
|           |                   |           |           | ( |           |
|           |                   |           |           | g |           |
|           |                   |           |           | / |           |
|           |                   |           |           | s |           |
|           |                   |           |           | t |           |
|           |                   |           |           | a |           |
|           |                   |           |           | r |           |
|           |                   |           |           | t |           |
|           |                   |           |           | ) |           |
|           |                   |           |           | ] |           |
|           |                   |           |           | { |           |
|           |                   |           |           | . |           |
|           |                   |           |           | u |           |
|           |                   |           |           | n |           |
|           |                   |           |           | d |           |
|           |                   |           |           | e |           |
|           |                   |           |           | r |           |
|           |                   |           |           | l |           |
|           |                   |           |           | i |           |
|           |                   |           |           | n |           |
|           |                   |           |           | e |           |
|           |                   |           |           | } |           |
+-----------+-------------------+-----------+-----------+---+-----------+
| Fuel      | [EIO-LCA          | Based on  |           |   |           |
|           | Impa              | fuel      |           |   |           |
| P         | cts]{.underline}: | con       |           |   |           |
| roduction | (3)               | sumption. |           |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | Non-renew. energy | 3.39      | 1.05      |   | 0.710     |
|           | use               | MJ/mile   | MJ/min.   |   | MJ/start  |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | Ozone-depl.       | 0         | 0         |   | 0         |
|           | emissions         |           |           |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | Global warm.      | 162.8     | 50.2      |   | 34.1      |
|           | emissions         |           |           |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | SO~2~ emissions   | 0.234     | 0.072     |   | 0.049     |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | CO emissions      | 0.200     | 0.062     |   | 0.042     |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | NO~2~ emissions   | 0.296     | 0.091     |   | 0.062     |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | VOC emissions     | 0.093     | 0.029     |   | 0.020     |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | Pb emissions      | 0         | 0         |   | 0         |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | PM-10 emissions   | 0.030     | 0.009     |   | 0.006     |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | TRI air emissions | 0.001     | ≈ 0       |   | ≈ 0       |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | RCRA wastes       | 0.177     | 0.055     |   | 0.037     |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | Base-metal ore    | 1.794     | 0.553     |   | 0.376     |
|           | depletion         |           |           |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | Prec. metal ore   | 0.264     | 0.082     |   | 0.055     |
|           | depletion         |           |           |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
| Vehicle   | [EIO-LCA          | Based on  |           |   |           |
|           | Impa              | vehicle   |           |   |           |
| P         | cts]{.underline}: | mileage   |           |   |           |
| roduction | (3)               | only.     |           |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | Non-renew. energy | 2.91      | MJ/mile   |   |           |
|           | use               |           |           |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | Ozone-depl.       | 0         | kg        |   |           |
|           | emissions         |           | CF        |   |           |
|           |                   |           | C-equival |   |           |
|           |                   |           | ents/mile |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | Global warm.      | 207.2     | g         |   |           |
|           | emissions         |           | CO~2      |   |           |
|           |                   |           | ~-equival |   |           |
|           |                   |           | ents/mile |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | SO~2~ emissions   | 0.654     | g/mile    |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | CO emissions      | 0.982     | g/mile    |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | NO~2~ emissions   | 0.524     | g/mile    |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | VOC emissions     | 0.241     | g/mile    |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | Pb emissions      | 0         | g/mile    |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | PM-10 emissions   | 0.071     | g/mile    |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | TRI air emissions | 0.096     | g/mile    |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | RCRA wastes       | 1.081     | g/mile    |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | Base-metal ore    | 55.77     | g/mile    |   |           |
|           | depletion         |           |           |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | Prec. metal ore   | 10.75     | g/mile    |   |           |
|           | depletion         |           |           |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
| Vehicle   | [Non-recov.       | Based on  |           |   |           |
|           | was               | vehicle   |           |   |           |
| Disposal  | tes]{.underline}: | mileage   |           |   |           |
|           | (4)               | only.     |           |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
|           | Landfilled wastes | 6.82      | g/mile    |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+
| \(4\)     |                   |           |           |   |           |
| L         |                   |           |           |   |           |
| andfilled |                   |           |           |   |           |
| wastes    |                   |           |           |   |           |
| are the   |                   |           |           |   |           |
| only      |                   |           |           |   |           |
| disposal  |                   |           |           |   |           |
| impact    |                   |           |           |   |           |
| modeled.  |                   |           |           |   |           |
| Over 75%  |                   |           |           |   |           |
| of the    |                   |           |           |   |           |
| mass of   |                   |           |           |   |           |
| the       |                   |           |           |   |           |
|           |                   |           |           |   |           |
| vehicle   |                   |           |           |   |           |
| is        |                   |           |           |   |           |
| assumed   |                   |           |           |   |           |
| to be     |                   |           |           |   |           |
| recycled, |                   |           |           |   |           |
| which     |                   |           |           |   |           |
| consumes  |                   |           |           |   |           |
| energy    |                   |           |           |   |           |
| and       |                   |           |           |   |           |
| materials |                   |           |           |   |           |
| and       |                   |           |           |   |           |
| generates |                   |           |           |   |           |
|           |                   |           |           |   |           |
| material  |                   |           |           |   |           |
| "cr       |                   |           |           |   |           |
| edits"--- |                   |           |           |   |           |
| materials |                   |           |           |   |           |
| returned  |                   |           |           |   |           |
| to the    |                   |           |           |   |           |
| economy.  |                   |           |           |   |           |
| However,  |                   |           |           |   |           |
| di        |                   |           |           |   |           |
| fferences |                   |           |           |   |           |
| among     |                   |           |           |   |           |
|           |                   |           |           |   |           |
| vehicle   |                   |           |           |   |           |
| types and |                   |           |           |   |           |
| routing/s |                   |           |           |   |           |
| cheduling |                   |           |           |   |           |
| alt       |                   |           |           |   |           |
| ernatives |                   |           |           |   |           |
| based on  |                   |           |           |   |           |
| them are  |                   |           |           |   |           |
| assumed   |                   |           |           |   |           |
| ne        |                   |           |           |   |           |
| gligible. |                   |           |           |   |           |
+-----------+-------------------+-----------+-----------+---+-----------+

<table>
<colgroup>
<col style="width: 16%" />
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<col style="width: 5%" />
<col style="width: 5%" />
<col style="width: 4%" />
</colgroup>
<tbody>
<tr class="odd">
<td colspan="17"><strong>Table A5. Combined Life-Cycle Environmental
Impacts for Modeled Vehicle Types</strong></td>
</tr>
<tr class="even">
<td rowspan="2"><h4 id="section-56"></h4>
<h4 id="impact-1">Impact</h4></td>
<td colspan="4"><h4 id="ld-gasoline-powered-minivan-1">LD
Gasoline-Powered “Minivan”</h4></td>
<td colspan="4"><h4 id="ld-cng-powered-1">LD CNG-Powered </h4>
<p>“<u>Minivan</u>”</p></td>
<td colspan="4"><h4 id="md-gasoline-powered-1">MD Gasoline-Powered </h4>
<p>“<u>Shuttle Bus</u>”</p></td>
<td colspan="4"><h4 id="md-diesel-powered-1">MD Diesel-Powered</h4>
<p>“<u>Shuttle Bus</u>”</p></td>
</tr>
<tr class="odd">
<td>g/mile</td>
<td>g/min.</td>
<td>g/start</td>
<td>g/day</td>
<td>g/mile</td>
<td>g/min.</td>
<td>g/start</td>
<td>g/day</td>
<td>g/mile</td>
<td>g/min.</td>
<td>g/start</td>
<td>g/day</td>
<td>g/mile</td>
<td>g/min.</td>
<td>g/start</td>
<td>g/day</td>
</tr>
<tr class="even">
<td colspan="17"><u>Air Emissions</u>:</td>
</tr>
<tr class="odd">
<td>NMOG (VOC)</td>
<td>0.4445</td>
<td>0.3041</td>
<td>0.2417</td>
<td></td>
<td>0.5600</td>
<td>0.0140</td>
<td>0.0092</td>
<td></td>
<td>0.6419</td>
<td>0.5189</td>
<td>0.5486</td>
<td></td>
<td>0.9862</td>
<td>0.1380</td>
<td>0.0940</td>
<td></td>
</tr>
<tr class="even">
<td>Methane</td>
<td>0.0087</td>
<td>0.0526</td>
<td>0.0160</td>
<td></td>
<td>6.5400</td>
<td>0.3589</td>
<td>0.2480</td>
<td></td>
<td>0.0310</td>
<td>0.0749</td>
<td>0.0370</td>
<td></td>
<td>0.0176</td>
<td>0.0054</td>
<td>0.0037</td>
<td></td>
</tr>
<tr class="odd">
<td>Formaldehyde</td>
<td>0.0013</td>
<td>0.0088</td>
<td>0.0067</td>
<td></td>
<td>0.0180</td>
<td>0.0099</td>
<td>0.0068</td>
<td></td>
<td>0.0060</td>
<td>0.1450</td>
<td>0.0168</td>
<td></td>
<td>0.0519</td>
<td>0.0160</td>
<td>0.0109</td>
<td></td>
</tr>
<tr class="even">
<td>1,3-Butadiene</td>
<td>0.0003</td>
<td>0.0018</td>
<td>0.0013</td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td>0.0012</td>
<td>0.0029</td>
<td>0.0034</td>
<td></td>
<td>0.0021</td>
<td>0.0006</td>
<td>0.0004</td>
<td></td>
</tr>
<tr class="odd">
<td>Acetaldehyde</td>
<td>0.0003</td>
<td>0.0018</td>
<td>0.0013</td>
<td></td>
<td>0.0020</td>
<td>0.0001</td>
<td>0.0001</td>
<td></td>
<td>0.0012</td>
<td>0.0029</td>
<td>0.0034</td>
<td></td>
<td>0.0104</td>
<td>0.0032</td>
<td>0.0022</td>
<td></td>
</tr>
<tr class="even">
<td>Toluene</td>
<td>0.0060</td>
<td>0.0352</td>
<td>0.0276</td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td>0.0243</td>
<td>0.0587</td>
<td>0.0674</td>
<td></td>
<td>0.0041</td>
<td>0.0013</td>
<td>0.0009</td>
<td></td>
</tr>
<tr class="odd">
<td>Benzene</td>
<td>0.0021</td>
<td>0.0123</td>
<td>0.0097</td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td>0.0085</td>
<td>0.0205</td>
<td>0.0237</td>
<td></td>
<td>0.0021</td>
<td>0.0006</td>
<td>0.0004</td>
<td></td>
</tr>
<tr class="even">
<td>Methyl t-Butyl Ether</td>
<td>0.0042</td>
<td>0.0176</td>
<td>0.0149</td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td>0.0128</td>
<td>0.0309</td>
<td>0.0377</td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr class="odd">
<td>SO<sub>x</sub> (SO<sub>2</sub>)</td>
<td>1.083</td>
<td>0.068</td>
<td>0.046</td>
<td></td>
<td>0.928</td>
<td>0.005</td>
<td>0.003</td>
<td></td>
<td>1.203</td>
<td>0.121</td>
<td>0.054</td>
<td></td>
<td>1.077</td>
<td>0.083</td>
<td>0.057</td>
<td></td>
</tr>
<tr class="even">
<td>NO<sub>x</sub> (NO<sub>2</sub>)</td>
<td>1.088</td>
<td>0.189</td>
<td>0.408</td>
<td></td>
<td>1.714</td>
<td>0.145</td>
<td>0.0992</td>
<td></td>
<td>2.176</td>
<td>0.323</td>
<td>1.383</td>
<td></td>
<td>4.593</td>
<td>0.359</td>
<td>0.244</td>
<td></td>
</tr>
<tr class="odd">
<td>CO</td>
<td>3.025</td>
<td>6.248</td>
<td>2.959</td>
<td></td>
<td>2.669</td>
<td>0.036</td>
<td>0.0249</td>
<td></td>
<td>6.048</td>
<td>12.403</td>
<td>9.244</td>
<td></td>
<td>2.018</td>
<td>0.332</td>
<td>16.042</td>
<td></td>
</tr>
<tr class="even">
<td>GWP (CO<sub>2</sub> / CO<sub>2</sub>-equiv.)</td>
<td>867.2</td>
<td>154.0</td>
<td>104.3</td>
<td></td>
<td>936.2</td>
<td>32.3</td>
<td>22.2</td>
<td></td>
<td>1302.1</td>
<td>273.1</td>
<td>121.6</td>
<td></td>
<td>860.2</td>
<td>73.8</td>
<td>50.1</td>
<td></td>
</tr>
<tr class="odd">
<td>PM-10</td>
<td>0.148</td>
<td>0.009</td>
<td>0.006</td>
<td></td>
<td>0.1466</td>
<td>0.023</td>
<td>0.0151</td>
<td></td>
<td>0.188</td>
<td>0.016</td>
<td>0.007</td>
<td></td>
<td>0.116</td>
<td>0.009</td>
<td>0.006</td>
<td></td>
</tr>
<tr class="even">
<td>Diesel PM-10 (DPM-10)</td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td>0.0601</td>
<td>0.0230</td>
<td>0.0156</td>
<td></td>
</tr>
<tr class="odd">
<td>TRI air emissions</td>
<td>0.042</td>
<td>≈ 0</td>
<td>≈ 0</td>
<td></td>
<td>0.044</td>
<td>≈ 0</td>
<td>≈ 0</td>
<td></td>
<td>0.038</td>
<td>0.001</td>
<td>≈ 0</td>
<td></td>
<td>0.041</td>
<td>≈ 0</td>
<td>≈ 0</td>
<td></td>
</tr>
<tr class="even">
<td colspan="17"><u>Other Impacts</u>:</td>
</tr>
<tr class="odd">
<td>Non-renew. energy use</td>
<td>7.488</td>
<td>0.982</td>
<td>0.668</td>
<td></td>
<td>7.024</td>
<td>0.069</td>
<td>0.047</td>
<td></td>
<td>13.135</td>
<td>1.760</td>
<td>0.786</td>
<td></td>
<td>6.968</td>
<td>1.050</td>
<td>0.710</td>
<td></td>
</tr>
<tr class="even">
<td>Fuel use (in gasoline eq.)*</td>
<td>0.0498</td>
<td>0.0125</td>
<td>0.0086</td>
<td></td>
<td>0.0454</td>
<td>0.0010</td>
<td>0.0007</td>
<td></td>
<td>0.0889</td>
<td>0.0223</td>
<td>0.0100</td>
<td></td>
<td>0.0387</td>
<td>0.0157</td>
<td>0.0107</td>
<td></td>
</tr>
<tr class="odd">
<td>Base-metal ore depletion</td>
<td>66.682</td>
<td>0.520</td>
<td>0.354</td>
<td></td>
<td>71.280</td>
<td>0.037</td>
<td>0.025</td>
<td></td>
<td>60.119</td>
<td>0.929</td>
<td>0.415</td>
<td></td>
<td>65.804</td>
<td>0.553</td>
<td>0.376</td>
<td></td>
</tr>
<tr class="even">
<td>Prec.-metal ore depletion</td>
<td>12.724</td>
<td>0.076</td>
<td>0.052</td>
<td></td>
<td>13.615</td>
<td>0.005</td>
<td>0.004</td>
<td></td>
<td>11.385</td>
<td>0..137</td>
<td>0.061</td>
<td></td>
<td>12.554</td>
<td>0.082</td>
<td>0.055</td>
<td></td>
</tr>
<tr class="odd">
<td>RCRA Wastes</td>
<td>1.466</td>
<td>0.051</td>
<td>0.035</td>
<td></td>
<td>1.525</td>
<td>0.004</td>
<td>0.002</td>
<td></td>
<td>1.468</td>
<td>0.092</td>
<td>0.041</td>
<td></td>
<td>1.428</td>
<td>0.055</td>
<td>0.037</td>
<td></td>
</tr>
<tr class="even">
<td>Non-recycled solid waste</td>
<td>4.800</td>
<td></td>
<td></td>
<td></td>
<td>5.560</td>
<td></td>
<td></td>
<td></td>
<td>5.190</td>
<td></td>
<td></td>
<td></td>
<td>6.82</td>
<td></td>
<td></td>
<td></td>
</tr>
<tr class="odd">
<td colspan="17"><p>* Fuels are considered in terms of
gasoline-equivalents. Gallons of No. 2 diesel fuel and CNG (3,000 psi)
are converted to gasoline equivalent units based on heat content values
reported</p>
<p>by MacLean (1998). The conversion factors are: 1 gallon diesel =
1.148 gallons gasoline-equivalent, 1 gallon CNG = 0.227 gallons
gasoline-equivalent.</p></td>
</tr>
</tbody>
</table>

**Environmental Impact Basis and Operating Cost "Notes"**

The following notes pertain to, and provide details concerning,
calculation of paratransit life-cycle impacts presented in Tables A1 to
A4. Impacts, in particular operating emissions, are intended to be
representative of the various types of paratransit vehicles modeled,
that is, for [generic classes]{.underline} of vehicles as opposed to any
specific vehicle models, makes, or years. Moreover, even if specific
makes and models of vehicles were considered, operating emissions would
be significantly influenced by factors such as mileage, state of
maintenance, temperature and humidity, etc. (CARB, 2000). This is to
say, while certain impacts (pollutant emissions) were estimated by
relatively crude techniques, where literature was not readily available,
the accuracy of the estimated values should be viewed in the previous
context.

[GENERAL]{.underline}

\(1\) In the paratransit LCI model, for the vehicle operation life-cycle
stage, impacts are determined as a function of VMT (travel distance),
idling time, and number of engine starts. Impacts for fuel production
and distribution are calculated based on fuel consumed, which is
calculated for each of the previous activities in the previous
determination. Impacts for other life-cycle impacts are attributed only
to vehicle operation.

\(2\) EMFAC/Burden vehicle emissions were modeled for the Los Angeles
County vehicle fleet, for calendar year 2001, limited to vehicle model
years 1998 through 2000. EMFAC default modeling parameters were used;
and annual average emissions were requested. Emission rates were
calculated from Burden data by dividing total emissions by total miles
or total starts. For the fleet comprised on model years 1998 to 2000,
the simulated driving cycle includes about 6.5 starts. (See CARB, 2000,
July.) Since the EMFAC/Burden model vehicle activity is based on the
fleet average, the total number of vehicle starts is the number of
vehicles times 6.5, or the number of trips reported in the Burden
results. Thus, the impact "per start" is the Burden total "start"
emissions divided by this number.

\(3\) The EMFAC driving cycle includes brief periods of zero mph or
near-zero mph travel; and, emissions from these periods are included in
"running" emissions reported by Burden. And, in the paratransit LCI
model, they are treated likewise, i.e., as part of "running" or
in-transit emissions. The "idling" emission component of vehicle
operation in the paratransit LCI model pertains to idling that occurs
during passenger boarding and discharging. And, the data used for these
emissions were taken primarily from literature sources. (See Note 11.)

\(4\) For the vehicle fleet and EMFAC run described in Note 2, the
Burden results (emissions are in tons/day) for light-duty gasoline
powered passenger vehicles (with exhaust catalyst) are:

Vehicles: 732, 403 Trips: 4,774,282

VMT/1000: 29,811 Gasoline consumed: 1, 484,000 gallons

(tons) [TOG]{.underline} [CO]{.underline} [NO~x~]{.underline}
[CO~2~]{.underline} [PM10]{.underline}

Running 1.95 52.8 6.38 14,010 0.21

Start 1.5 15.4 1.83 380 0.01

Hot Soak (evap.) 0.08

Running (evap.) 0.55

Tire wear 0.26

Break wear 0.42

Lead 0

SO~x~ 0.19

\(5\) In the EMFAC model, fugitive organic emissions (diurnal, hot soak,
running, resting) are modeled differently. Diurnal and resting emissions
occur when the vehicle is not operating. Hot soak emissions occur within
an hour after the vehicle has been turned off. Running emissions are
evaporative fuel losses while the vehicle is running.

In the paratransit LCI model, diurnal and resting evaporative emissions
are [not]{.underline} considered because they are not functions of
vehicle scheduling---they occur whether the vehicle has been operated or
not. Hot soak emissions occur as a result of engine starts; and, in the
LCI model they are attributed on this basis. Running emissions are a
function of vehicle activity---primarily VMT, but, also, to a small
extent, idling. (See CARB, 2000b; CARB,1996, Oct.) In the paratransit
LCI model, they are modeled solely as a function of VMT or distance.
While this results in a slight error, it is only the
[difference]{.underline} in error among routing alternatives that are
relevant; and, these differences are assumed to be negligible.

\(6\) EMFAC/Burden report organic emissions as (user specified) TOG
(total organic gases), ROG (reactive organic gasses), THC (total
hydrocarbon), and methane (CARB, 2000b). THCs include only C-H compounds
and exclude carbonyls. NMHC (non-methane hydrocarbon equivalent) is a
term used by USEPA and it includes all non-oxygenated species (including
methane) plus the hydrocarbon fraction of oxygenated species including
carbonyls. VOCs (volatile organic compounds), a term also in general
use, exclude methane and other exempt/non-reactive species. VOC is
assumed to be approximately equivalent to NMHC (MacLean, 1998).

From the EMFAC conversion factors, the following THC : TOG : ROG :
methane ratios are calculated (for LD, gasoline powered vehicle):

[Running]{.underline} [Starting]{.underline} [Hot
Soak/Running]{.underline} [Diurnal/Resting]{.underline}

1:1.07:0.92:0.14 1:1.06:1:0.06 1:1.06:1:0.06 1:1.12:1.12:0.

USEPA (2000, July) reports exhaust [VOCs]{.underline} for a typical
gasoline-powered engine are comprised of the following organic air
toxics: acetaldehyde (0.5%), 1,3-butadiene (0.5%), formaldehyde (1%),
benzene (4%), and toluene (10%).

[LD GASOLINE-POWERED VEHICLE IMPACTS]{.underline}

\(7\) TOG emissions are determined, based on EMFAC/Burden data, to be
0.0594 g/mile running exhaust, 0.0168 g/mile running evaporative, 0.285
g/start, and 0.015 g/start (hot soak). The latter value is an
approximation in that it assumes all starts produce hot soak emissions.
The total organic exhaust emissions are 0.105 g/mile, including running
and start exhaust emissions.

Based on the EMFAC conversion factors, TOG running exhaust emissions are
estimated to be comprised of 87% non-methane organic gases (NMOG) and
13% methane. TOG start, hot soak, and running evaporative emissions are
estimated to be comprised of 94.5% NMOG and 5.5% methane. Then, by
multiplying the previous emissions by these compositions:

[Running (g/mile)]{.underline} [Start (g/start)]{.underline}

NMOG 0.0676 0.284

Methane 0.00865 0.016.

For comparison purposes, total exhaust emissions are calculated as 0.105
g/mile, comprised of approximately 0.094 g/mile NMOG. Black, Tejada, and
Gurevich (1998) tested several models of vehicles using reformulated
gasoline (RFG) and the FTP test cycle. They report total NMOG emissions
on the order of 0.11 to 0.15 g/mile. USDoE (1994) reports methane
emissions, based on USEPA's MOBILE5 model, as 0.008 g/mile. Thus, given
differences in fuels, vehicles or fleets, test cycles, and other
factors, the previously calculated values are seen as reasonable.

\(8\) NMOG exhaust emissions are further decomposed into constituents of
1,3-butadiene, formaldehyde, benzene, acetaldehyde, and toluene based on
experimental data reported by Winebrake and Deaton (1999), Black, et al
(1998), as well as from data from USEPA (2000, July) as 1,3-butadiene
(0.5%), formaldehyde (2.5%), benzene (3.5%), acetaldehyde (0.5%), and
toluene (10%). Additionally, based on Black, et al, exhaust emissions
are assumed to be comprised of MTBE (5%).

Evaporative emissions would not be expected to contain combustion
products (such as aldehydes), but to more closely resemble the
composition of the fuel. (See Black, et al.) Therefore, evaporative NMOG
emissions are estimated, using data from Black, et al, as benzene (2%),
toluene (5%), and MTBE (10%). The composition of NMOG emissions is
assumed to be the same for both running exhaust and start-exhaust
emissions. Likewise, the composition of evaporative emissions is assumed
to be the same for both running and hot-soak evaporative emissions.

\(9\) Based on the emissions rates and compositions above, the emissions
rates for all species are calculated as:

[g/mile]{.underline} [g/start]{.underline}

NMOG-other 0.0535 0.2220

Methane 0.0087 0.0160

Benzene 0.0021 0.0097

Toluene 0.0060 0.0276

Formaldehyde 0.0013 0.0067

1,3-Butadiene 0.0003 0.0013

Acetaldehyde 0.0003 0.0013

MTBE 0.0042 0.0149

> The total emissions are 0.0764 g/mile and 0.2295g/start. Importantly,
> it should be noted that these values, and those calculated for other
> life-cycle impacts, are intended to be representative rather than
> specific to a particular vehicle make and model, since a generic
> vehicle is assumed. Moreover, actual emission rates are a function of
> vehicle age, mileage, mechanical condition, as well as actual driving
> conditions. Thus, estimation of these impacts based on a more
> extensive survey of available data is not warranted.

\(10\) Emission rates of CO, NO~x~, CO~2~, and PM-10 are taken from
EMFAC/Burden data (see previous note in "General" section) by dividing
the running and start exhaust quantities by the number of miles and
starts, respectively. They are found to be:

[g/mile]{.underline} [g/start]{.underline} [g/mile inc.
starts]{.underline}

CO 1.61 2.92 2.07

NO~x~ 0.19 0.35 0.25

CO~2~ 427 72.3 438

SO~x~ 0.006 \-\-\-\-- 0.006.

A good correlation is found between these values and others reported in
the literature. For example, Black, et al, based on actual testing,
report NO~x~ emission rates of 0.15 to 0.29 g/mile and CO emission rates
of 1.44 to 3.36 g/mile.

\(11\) PM-10 emission rates can also be calculated from EMFAC/Burden
data. However, start emissions, which are negligible, are excluded.
Reported data includes that for brake wear. Based on Armstrong (1994),
the particulates from brake wear are assumed to be comprised to 10
percent copper and 0.5 percent zinc. Therefore, the calculated values
are:

[g/mile]{.underline}

Cu 0.0013

Zn 0.0001

PM-10 (other) 0.0256

\(12\) Idling emissions for VOC, CO, and NO~x~ are taken from USEPA
(1998, April), as 0.352, 6.19, and 0.103 g/minute, respectively. VOC
(NMOG) constituents are (crudely) assumed to be present at the same
ratios as running exhaust emissions. Methane emissions are then
estimated using the NMOG : methane ratio for running emissions.

\(13\) Fuel consumption is approximated from EMFAC/Burden data as 20.1
mile/gallon. Idling fuel consumption is assumed to be 0.75 gallons/hour
or 0.0125 gallon/minute. Idling CO~2~ emissions are estimated based on
fuel consumption (running). Fuel consumption per start is then estimated
based on CO~2~ (start) emissions.

# MEDIUM-DUTY GASOLINE-POWERED VEHICLE ("SHUTTLE BUS") IMPACTS

\(14\) For the vehicle fleet and EMFAC run described in Note 2, the
Burden results (emissions are in tons/day) for medium-duty gasoline
powered trucks (with exhaust catalyst) are:

Vehicles: 131,771 Trips: 1,299,077

VMT/1000: 5,860 Gasoline consumed: 520,830 gallons

(tons) [TOG]{.underline} [CO]{.underline} [NO~x~]{.underline}
[CO~2~]{.underline} [PM10]{.underline}

Running 1.541 29.66 6.50 4880 0.07

Start 0.89 0.943 13.16 120 0.01

Hot Soak (evap.) 0.02

Running (evap.) 0.05

Tire + brake wear 0.25

Lead 0

SO~x~ 0.07

Then, using the same composition (NMOG : methane) and similar
calculation as for LD gasoline-powered passenger vehicles (Note 7):

[Running emissions (g/mile)]{.underline} [Start emissions
(g/start)]{.underline}\*

NMOG 0.216 0.637

Methane 0.031 0.037

(\* Start emissions in g/start calculated by dividing total start plus
hot soak emissions by number of vehicle trips.)

\(15\) NMOG emissions are further decomposed into constituents for
running/start and evaporative emissions following the same composition
and calculation as for LD gasoline-powered passenger vehicles (see Notes
8 and 9). These emissions are:

[g/mile]{.underline} [g/start]{.underline}

NMOG-Other 0.1931 0.5256

Methane 0.0310 0.0370

Benzene 0.0085 0.0237

Toluene 0.0243 0.0674

Formaldehyde 0.0060 0.0168

1,3-Butadiene 0.0012 0.0034

Acetaldehyde 0.0012 0.0034

MTBE 0.0128 0.0337

\(16\) CO, NO~x~, CO~2~, SO~x~, and PM-10 emissions are taken directly
from EMFAC/Burden data (see Note 10):

[g/mile]{.underline} [g/start]{.underline}

CO 4.596 9.198

NO~x~ 1.007 1.314

CO~2~ 743.8 83.88

SO~x~ 0.011 \-\--

PM-10 0.050 0.007

\(17\) Idling emissions for VOC (NMOG), CO, and NO~x~ from USEPA (1998,
April) for heavy-duty (\>8,500 lbs.) gasoline trucks: VOC (0.597
g/min.), CO (12.3 g/min.), and NO~x~ (0.170 g/min.). VOC (NMOG)
constituents calculated analogously to those for LD gasoline-powered
passenger vehicles. See Note 12. CO~2~ idling emissions calculated
analogously to those for LD gasoline-powered passenger vehicles, based
on idling fuel consumption of 0.0223 gal./min. See Note 13. Fuel
consumption per start (0.0100 gal./start) estimated based upon CO~2~
start emissions. See Note 13.

# MEDIUM-DUTY DIESEL-POWERED VEHICLE ("SHUTTLE BUS") IMPACTS

> \(18\) Diesel vehicle emission factors consider exhaust emissions
> only, due to unavailability of data for evaporative emissions. Diesel
> running exhaust emissions from EMFAC/Burden data (see Note 2) for
> medium-duty diesel trucks:

Vehicles: 14,392 Trips: 122,660

VMT/1000: 756 Fuel consumed: 33,600 gal.

(tons) [THC]{.underline} [TOG]{.underline} [CO]{.underline}
[NO~x~]{.underline} [CO~2~]{.underline} [DPM-10]{.underline}
[PM-10]{.underline} [SO~x~]{.underline}

0.25 0.36 0.53 3.05 370 0.05 0.02 0.03

Diesel particulate emissions (DPM-10) are exhaust emissions; and, these
are differentiated from other particulate emissions. PM-10 emissions are
due to brakes and tire wear, as reported by EMFAC/Burden.

Diesel emission TOG:THC:methane ratio is from CARB (2000b) and is
assumed the same for running, start, and idling exhaust emissions:

TOG = 1.4417 THC, CH~4~ = 0.0408 TOG.

\(19\) From the above, running exhaust emissions are calculated to be:

[g/mile]{.underline} [g/mile]{.underline}

NMOG : 0.4148 CO~2~: 444

CH~4~: 0.0176 SO~x~: 0.0369

CO: 0.6366 PM-10: 0.0240

NO~x~: 3.6632 DPM-10: 0.0601

> \(20\) Diesel exhaust NMOG is assumed to be comprised of the same
> constituents as gasoline exhaust NMOG, although at different
> proportions, based on Nylund and Lawson (2000). The composition is
> assumed to be: benzene (0.5%), toluene (1.0%), formaldehyde (12.5%),
> 1,3-butadiene (0.5%), and acetaldehyde (2.5%). On this basis, running
> exhaust emissions are calculated to be:

[g/mile]{.underline} [g/mile]{.underline}

NMOG-Other (VOC): 0.3443 Formaldehyde: 0.0519

Methane: 0.0176 1.3-Butadiene: 0.0021

Benzene: 0.0021 Acetaldehyde: 0.0104

Toluene: 0.0041

> \(21\) Diesel vehicle idling emissions are assumed (as mid-point
> values) based on data reported by USEPA (1998, April) and McCormick,
> Graboski, Alleman, and Yanowitz (2000). The values used are:
>
> [g/min]{.underline}.

NMOG: 0.1280

CH~4~: 0.0054

CO: 0.2695

NO~x~: 0.2675

DPM-10: 0.0230

\(22\) Diesel vehicle idling CO~2~ emissions are calculated as a ratio,
based on NMOG emissions, to running emissions to be 23.6 g/min.

\(23\) Diesel idling fuel consumption is calculated similarly, based on
NMOG emissions and calculated running fuel consumption rate (22.5 mpg)
as 0.0137 gallon/minute.

> \(24\) Due to lack of reported data, diesel "start" fuel consumption
> is (crudely) estimated by analogy to LD gasoline vehicle "start" fuel
> consumption as 0.0093 gallon/start.

(25) Diesel "start" emissions are assumed to be identical in composition
     to idling emissions and are calculated based on idling emissions
     and the ratio of start : idling fuel consumption.

## LD CNG-POWERED VEHICLE ("MINIVAN") IMPACTS

\(26\) The following CNG-powered vehicle ("minivan") [running
emissions]{.underline} are assumed, based on data reported by Deaton and
Winebrake (2000) for a fleet of LEV-certified Dodge vans with 5.2 l
fuel-injection engines:

[g/mile]{.underline} [g/mile]{.underline}

CO 1.2 NO~x~ 0.75

NMHC 0.2 CO~2~ 510

\(27\) The following CNG-powered vehicle [idling emissions]{.underline}
are assumed based on data reported by McCormick, et al (2000) for a
fleet of LEV-certified busses with 5.9 l engines:

[g/minute]{.underline} [g/minute]{.underline}

CO 0.032 NOx 0.139

THC 0.369 PM-10 0.022

\(28\) Start and running [evaporative]{.underline} emissions are assumed
to be zero for CNG-powered vehicles (MacLean, 1998).

\(29\) Based on data reported by MacLean, CNG hydrocarbon emissions are
assumed to be comprised of 97% CH~4~ and 3% NMOG, where NMOG is
comprised of both combustion products as well as the non-methane
constituents of unburned fuel. Unburned fuel is (crudely) assumed to
constitute 90% of NMOG. According to Carslow and Fricker (1995), CNG
(fuel) is comprised of 93% methane and 7% other alkanes (which include
VOCs and non-VOCs). The primary oxygenated combustion products are
formaldehyde and acetaldehyde, found at a ratio of 8.75:1 (MacLean).

\(30\) On the above basis, the hydrocarbon and other CNG-powered vehicle
running and idling emissions are assumed to be the values below. The
hydrocarbon compositions of running and idling emissions are assumed to
be the same. PM-10 running emissions are assumed to be primarily
comprised of tire and brake particulates (from EMFAC/Burden results);
and, the same value as that for the gasoline-powered LD vehicle (0.0256
g/mile) is assumed. Idling CO~2~ emissions are estimated using ratios
(running:idling THC emissions) and running CO~2~ emissions.

\(31\) CNG-vehicle idling fuel consumption is calculated based upon
CO~2~ ratios and running fuel consumption and is calculated to be 0.011
gal. CNG/minute. CNG consumption is based on compressed (3000-3600 psi)
natural gas, reported in units of gallons, where one gallon CNG is equal
to approximately 0.24 gallons gasoline-equivalent (MacLean).

\(32\) According to MacLean, starting of CNG-fueled engines does not
require fuel enrichment, unlike starting of gasoline-fueled engines.
And, CNG engine "start" emissions are then assumed to be of composition
identical to running and idling emissions. CNG "start" emissions (and
fuel consumption) are estimated using the same idling : start ratio as
diesel-fueled engines.

FUEL-CYCLE, SERVICE, AND OTHER LIFE-CYCLE ENVIRONMENTAL IMPACTS---ALL
VEHICLE TYPES

\(33\) VOC (as NMOG) fueling emissions (for gasoline-fueled vehicles are
calculated based upon fuel consumed and emission rates reported by
DeLuchi (1993). He reports vehicle fueling emissions ranging from 0.00
to 2.44 grams VOC (NMOG) per gallon consumed, depending upon the vehicle
and pumpside emission controls in place. In 59 FR 16262 (April 6, 1994),
USEPA published a rule setting the allowable standard at 0.20
grams/gallon of fuel dispensed. This value is used for both gasoline and
diesel fuels; and, "per mile," "per minute (idle)," and "per start"
values are calculated using the previously calculated fuel consumptions
for each (with the same simplifying assumption used to calculate fuel
consumption, namely, EMFAC/Burden fuel mileage is based on running miles
only).

For CNG fueling, a loss of one gram per five gallons CNG is assumed,
together with the simplifying assumption that the emissions consists
entirely of methane.

\(34\) Environmental impact data for vehicle service and maintenance,
petroleum refining, and vehicle production is taken primarily from the
EIO-LCA database. As this data is based on economic transactions in
producer prices in 1992 dollars, current producer prices (e.g., for
gasoline, vehicles) are multiplied by a factor of 0.85 to convert
2000-year dollars to 1992-year dollars. The factor of 0.85 is based on
Implicit Price Deflators published by the USDoC Bureau of Economic
Analysis. (Alternatively, Producer Price Index factors might have been
used.)

The EIO-LCA data (Green Design Initiative, 2000) for \$1 million of
incremental production is:

[Impact]{.underline} [Unit]{.underline} [Veh. Prod]{.underline}. [Petr.
Refining]{.underline} [Auto Service/Maint.]{.underline}
[Insurance]{.underline}

Energy TJ 14.247 109.1 9.278 3.732

ODP mt CFC-eq. 0 0 0 0

SO~2~ mt 3.208 7.509 2.124 0.773

CO mt 4.816 6.415 2.762 1.545

NO~2~ mt 2.569 9.533 1.527 0.623

VOC mt 1.182 3.000 0.415 0.420

Pb mt 0.003 0 0.001 0

PM-10 mt 0.346 0.970 0.209 0.099

GWP mt CO~2~-eq. 1015.7 5234. 641.8 252.1

Base metal cons. mt 273.4 57.7 114.5 9.94

Prec. metal cons. mt 52.7 8.5 21.4 1.9

RCRA waste, shipped mt 5.3 5.7 2.36 0.706

TRI air releases mt 0.473 0.276 0.143 0.030

TRI air releases, mt 0.171 0.043 0.070 0.008

CMU-ET weighted

TRI offsite mt 1.308 0.244 0.477 0.045

TRI offsite, mt 10.348 1.069 4.58 0.387

CMU-ET weighted

**TRI emissions (quantities) shown in the life-cycle inventories for the
vehicle types are based on CMU Equivalent Toxicity rather than actual
(unadjusted) values.**

\(35\) Vehicle service and maintenance costs (excluding fuel) are
estimated, based on "popular" data such as that published by the
American Automobile Association, to be \$6,700 over a 90,000-mile
vehicle (LD gasoline-powered "minivan") lifetime. This is approximately
\$5,700 in 1992-year dollars, or \$0.063 1992-year dollars/mile when
allocated on a "per mile" basis. Service and maintenance costs for the
other vehicles are assumed to be proportional to the vehicles' purchase
prices and are allocated over the vehicles expected lifetimes:

> [Vehicle Type]{.underline} [Est. Life (miles)]{.underline} [Prod.
> Price (\$1992)]{.underline} [Maint.(\$1992)]{.underline} [\$1992
> maint./mile]{.underline} LD Gasoline 90,000 \$ 16,150 \$ 5,700 \$
> 0.063
>
> LD CNG 90,000 19,975 7,050 0.078
>
> MD Gasoline 175,000 31,450 11,100 0.063
>
> MD Diesel 200,000 40,800 14,400 0.072
>
> For purposes of determining EIO-LCA-based impacts arising from
> vehicles service and maintenance, 1992-year dollars are used (Green
> Design Initiative, 2000). For use in the vehicle scheduling objective
> function, current-year dollars (2000) are used.

\(36\) EIO-LCA fuel cycle emissions are based on a 1992-year dollar
(producer) price of \$0.72/gallon for unleaded gasoline. This
corresponds to a current-dollar producer price of approximately
\$0.85/gallon, which may be compared to current futures prices of
between \$0.85 and \$0.91/galon.

The EIO-LCA-based impacts in grams/mile, due to gasoline production, for
VOC, CO, NO~x~, SO~x~, and PM-10, respectively, are found to be 0.107,
0.230, 0.341, 0.269, and 0.035 for the LD gasoline-powered vehicle (20.1
miles per gallon). For comparison, DeLuchi (1993) reports these
emissions for refineries, including emissions from the generation of
purchased electricity. His values, respectively, are 0.054, 0.095,
0.137, 0.144, and 0.015 when converted to the same per mile basis. The
EIO-LCA results are seen as reasonable given the additional sectors
included.

EIO-LCA-based impacts due to the production of other fuels (CNG and
diesel) are calculated similarly, that is, based upon vehicle fuel
economy (mileage) and fuel [producer prices]{.underline} (\$1992) of:

Diesel: \$0.70 CNG: \$0.144.

> (For comparison purposes, MacLean reports \$1992 retail prices of
> \$1.10 (gasoline), \$1.07 (diesel), \$0.91 (CNG in gasoline
> equivalents), and \$0.22 (CNG per gallon).

\(37\) Vehicle production impacts are calculated from EIO-LCA data based
on the 1992 \$ producer prices in Note 35. Vehicle are also assumed to
have no salvage value. Allocated "per mile" (usage or depreciation)
costs are calculated by dividing the 1992\$ vehicle producer price by
the vehicle lifetime (see Note 35). Economic costs (Note 40) are
allocated based upon 2000\$ purchase price and vehicle lifetime.

\(38\) Fixed costs are those arising from insurance, licensing, and
financing activities; and, the indirect (equilibrium) environmental
impacts of these activities are non-trivial (Maclean). Fixed costs are
assumed to be equal to 15 percent of the vehicle purchase price (1992\$)
per year. While there is an intuitive basis for allocating the
environmental impacts from the other life-cycle stages---e.g., vehicle
and fuel production---on a "per mile" basis, there is no obvious
rationale for allocating the environmental impacts of the previous fixed
costs on the same basis. Instead, these are allocated on a "daily usage"
basis (where 365 potential days of usage per year is assumed). The
rationale for this is that if vehicles in the fleet are underutilized,
they potentially can be eliminated.

\(39\) According to USEPA (1999b, October), 75 percent of the vehicle
mass (of a typical vehicle) is recycled when scrapped, and the remainder
is landfilled. For simplicity, recycling is not included in the
life-cycle model, and only landfilled waste is considered based upon the
assumed vehicle weights:

LD gasoline-powered "minivan": 3,800 lbs.

LD CNG-powered "minivan": 4,400 lbs.

MD gasoline-powered "shuttle bus": 8,000 lbs.

MD diesel-powered "shuttle bus": 12,000 lbs.

### OPERATING (ECONOMIC) COSTS

\(40\) Vehicle economic operating costs are allocated on a "per mile"
basis (only). There are several reasons for this: convention, as both
much prior theoretical work as well as many practical applications
(e.g., , Chira-Chavala, 1999; Dessouky and Adam, 1998a, b) utilize
objective functions based on minimization of distance or
distance-related cost; in practice, paratransit providers may utilize
out-sourced vehicles, contracted on a "per mile" basis (Weidner, 2000);
and, in practice, paratransit operators may be provided vehicles and
compensated based upon minimization of distance (Weidner, 2000).

Relevant economic costs are:

\- vehicle depreciation, based on allocation of vehicle purchase price
(retail cost in\
2000\$)including ADA modification over the vehicle's useful life;

\- fuel cost (retail cost in 2000\$) calculated based upon fuel economy.

For the modeled vehicles, these costs (in 2000\$) are calculated to be:

[Deprec]{.underline}., [Fuel]{.underline}, [Fuel]{.underline},

[Retail price,\$]{.underline} [\$/mile]{.underline} [\$/gal]{.underline}
[MPG]{.underline}

LD-gas "minivan": 20,900 0.232 1.55 20.1

LD-CNG "minivan": 25,850 0.287 0.35 5

MD-gas "shuttle bus": 40,700 0.233 1.55 11.2

MD-diesel "shuttle bus": 52,800 0.264 1.44 22.5

Maint.,

[\$/mile]{.underline} [Total Operating Cost, \$/mi]{.underline}

LD-gas "minivan": 0.074 0.375

LD-CNG "minivan": 0.092 0.449

MD-gas "shuttle bus": 0.074 0.445

MD-diesel "shuttle bus": 0.085 0.413

Driver and other overhead costs are not included among relevant costs
because 1) they do not differ among vehicles or vehicle types, and 2)
they are not relevant in terms of the contractual performance incentives
and penalties by which paratransit operators are compensated (Access
Services, Inc., 2000).

**Additional References Cited**

Access Services, Inc. (2000). (Access Contractor) "Term and Conditions,"
received from Los Angeles Metropolitan Transportation Authority.

Carslaw, D., & Fricker, N. (1995). Natural gas vehicles. *Chemistry and
Industry*, [15]{.underline}, 593-596.

McCormick, R., Graboski, M., Alleman, T., & Yanowitz, J. (2000). Idle
emissions from heavy-duty diesel and natural gas vehicles at high
altitude*. Journal of the Air and Waste Management Association*,
[50]{.underline}, 1992-1998.

Nylund, N.-O., & Lawson, A. (2000). Exhaust Emissions from Natural Gas
Vehicles. Auckland, New Zealand: International Association for Natural
Gas Vehicles (IANGV). Available at: http://www.iangv.org/
html/sources/sources/reports.

[APPENDIX B: VEHICLE (PARTIAL UNIT) UTILITY FACTOR BASIS]{.underline}

**Reference Values for Calculation of Unit Utility Factors**

In general, because of assumed linear single-attribute value (utility)
functions, single-attribute utility functions for damage indicators
(attributes) D~j~ may be expressed as:

u(D~j~) = - ∑~i~ I~i~D~ij~ / D~j(REF)~, (B1)

where

D~ij~ = ∑~k~ D~ijk~ (B2)

in the case of impact-specific damage indicators (D~ijk~, e.g., EPS and
Eco-Indicator), and where

D~j(REF)~ ≥ max. ∑~i~ I~i(REF)~D~ij~. (B3)

That is, the reference quantity I~i(REF)~ is defined as the maximum
feasible quantity of stressor i among the stressors and
[alternatives]{.underline} considered. (We assume that the linearity of
the single-attribute preference function is valid over all outcome
ranges; however, we wish to constrain the range considered to one that
is realistic.)

The previous reference quantities are calculated based on the unit (per
mile, per engine start, and per minute idle) vehicle emissions factors
and an assumed "worst case" scenario based on the system simulated---the
number of vehicles in daily use and foreseeable maximum distance, idling
time, and engine starts per vehicle. (The unit emissions factors are
reported in the main body and the latter values may be determined by
system experimentation.) [Alternatively, the reference values themselves
may be directly determined based on experimentation, as a listing of
system-wide stressor quantities (totals) is provided as a simulation
output]{.underline}.

For illustration, we consider the four illustrative fleet compositions
and operational results shown on Table B1. Total stressor quantities
resultant of each scenario are calculated by multiplying unit stressor
emissions factors (e.g., grams of stressor i per mile, data reported in
main text body) and the respective scenario units (e.g., total number of
miles, engine starts, etc.) for each vehicle type. And, the emissions
are then summed across activities (e.g., transit, engine starts, etc.).
These results shown on Table B2.

The reference quantities that we would utilize [for this
example]{.underline} are also shown on Table B2. The quantities are
arbitrarily specified taking into account the fact that the scenarios do
not necessarily represent the "worst possible case" for the particular
fleet compositions for which actual emissions have been determined based
on a particular demand. (Our "rule of thumb" is to specify the reference
values as about twice the values expected from a "typical" scenario. The
simulation program itself contains errors traps to ensure that
calculated utility values for simulated system scenarios are within the
expected range.)

Similarly, on the same example basis, we can calculate reference values
for the damage indicators of interest, i.e., D~j(REF)~, utilizing the
reference quantities of Table B2 and the unit damage indicator values
(data reported in main text body) and combining like indicators across
impact categories (Equation B2) and stressors (Equation B1). The results
are provided in Table B3. Reference values for Resource Depletion and
Other Impacts impacts are simply the reference quantities (I~i(REF)~)
shown on Table B2; that is, for these, D~j(REF)~ ≡ I~i(REF)~, where I~i~
∈ D~j~ in this case.

+---------------+---------------+--------+--------+--------+--------+
| **Table B1.   |               |        |        |        |        |
| Basic Data    |               |        |        |        |        |
| for           |               |        |        |        |        |
| Illustrative  |               |        |        |        |        |
| Fleet         |               |        |        |        |        |
| Composition   |               |        |        |        |        |
| Example**     |               |        |        |        |        |
+---------------+---------------+--------+--------+--------+--------+
| [Vehicle      | [Variable     | [      |        |        |        |
| (Type)        | ]{.underline} | Altern |        |        |        |
| ]{.underline} |               | ative] |        |        |        |
|               |               | {.unde |        |        |        |
|               |               | rline} |        |        |        |
+---------------+---------------+--------+--------+--------+--------+
|               |               | *[A]{  | *[B]{  | *[C]{  | *[D]{  |
|               |               | .under | .under | .under | .under |
|               |               | line}* | line}* | line}* | line}* |
+---------------+---------------+--------+--------+--------+--------+
| Type I        | Number of     | 120    | 100    | 100    | 80     |
|               | vehicles      |        |        |        |        |
| (Gaso         |               |        |        |        |        |
| line-powered, |               |        |        |        |        |
| light-duty    |               |        |        |        |        |
| "minivan")    |               |        |        |        |        |
+---------------+---------------+--------+--------+--------+--------+
|               | Vehicle miles | 94,800 | 83,500 | 73,550 | 58,800 |
+---------------+---------------+--------+--------+--------+--------+
|               | Vehicle       | 1,320  | 1,080  | 1,160  | 960    |
|               | engine starts |        |        |        |        |
+---------------+---------------+--------+--------+--------+--------+
|               | Vehicle       | 19,200 | 15,050 | 15,650 | 13,600 |
|               | minutes       |        |        |        |        |
|               | idling        |        |        |        |        |
+---------------+---------------+--------+--------+--------+--------+
| Type II       | Number of     | 80     | 140    | 120    | 100    |
|               | vehicles      |        |        |        |        |
| (CNG-powered, |               |        |        |        |        |
| light-duty    |               |        |        |        |        |
| "minivan")    |               |        |        |        |        |
+---------------+---------------+--------+--------+--------+--------+
|               | Vehicle miles | 60,400 | 1      | 85,800 | 74,250 |
|               |               |        | 21,100 |        |        |
+---------------+---------------+--------+--------+--------+--------+
|               | Vehicle       | 840    | 1,330  | 1,360  | 1,210  |
|               | engine starts |        |        |        |        |
+---------------+---------------+--------+--------+--------+--------+
|               | Vehicle       | 12,400 | 19,700 | 19,200 | 16,950 |
|               | minutes       |        |        |        |        |
|               | idling        |        |        |        |        |
+---------------+---------------+--------+--------+--------+--------+
| Type III      | Number of     | 40     | 40     | 60     | 60     |
|               | vehicles      |        |        |        |        |
| (Gaso         |               |        |        |        |        |
| line-powered, |               |        |        |        |        |
|               |               |        |        |        |        |
| medium-duty   |               |        |        |        |        |
| "shuttle      |               |        |        |        |        |
| bus")         |               |        |        |        |        |
+---------------+---------------+--------+--------+--------+--------+
|               | Vehicle miles | 30,050 | 28,400 | 45,900 | 46,500 |
+---------------+---------------+--------+--------+--------+--------+
|               | Vehicle       | 440    | 480    | 630    | 590    |
|               | engine starts |        |        |        |        |
+---------------+---------------+--------+--------+--------+--------+
|               | Vehicle       | 5,800  | 7,400  | 11,050 | 10,800 |
|               | minutes       |        |        |        |        |
|               | idling        |        |        |        |        |
+---------------+---------------+--------+--------+--------+--------+
| Type IV       | Number of     | 40     | 0      | 0      | 40     |
|               | vehicles      |        |        |        |        |
| (Di           |               |        |        |        |        |
| esel-powered, |               |        |        |        |        |
| medium-duty   |               |        |        |        |        |
| "shuttle      |               |        |        |        |        |
| bus")         |               |        |        |        |        |
+---------------+---------------+--------+--------+--------+--------+
|               | Vehicle miles | 28,700 | 0      | 0      | 29,650 |
+---------------+---------------+--------+--------+--------+--------+
|               | Vehicle       | 410    | 0      | 0      | 450    |
|               | engine starts |        |        |        |        |
+---------------+---------------+--------+--------+--------+--------+
|               | Vehicle       | 6,050  | 0      | 0      | 6,850  |
|               | minutes       |        |        |        |        |
|               | idling        |        |        |        |        |
+---------------+---------------+--------+--------+--------+--------+
| TOTAL,        | Number of     | 280    | 280    | 280    | 280    |
|               | vehicles      |        |        |        |        |
| All Vehicle   |               |        |        |        |        |
| Types         |               |        |        |        |        |
+---------------+---------------+--------+--------+--------+--------+
|               | Vehicle miles | 2      | 2      | 2      | 2      |
|               |               | 13,950 | 33,300 | 05,250 | 09,200 |
+---------------+---------------+--------+--------+--------+--------+
|               | Vehicle       | 3,010  | 2,890  | 3,150  | 3,210  |
|               | engine starts |        |        |        |        |
+---------------+---------------+--------+--------+--------+--------+
|               | Vehicle       | 43,450 | 42,150 | 45,900 | 48,200 |
|               | minutes       |        |        |        |        |
|               | idling        |        |        |        |        |
+---------------+---------------+--------+--------+--------+--------+

+---------------------+---------+---------+---------+--------+--------+
| **Table B2.         |         |         |         |        |        |
| Life-Cycle          |         |         |         |        |        |
| Inventory for       |         |         |         |        |        |
| Alternatives in     |         |         |         |        |        |
| Illustrative        |         |         |         |        |        |
| Calculation**       |         |         |         |        |        |
|                     |         |         |         |        |        |
| (all quantities in  |         |         |         |        |        |
| kg unless otherwise |         |         |         |        |        |
| noted)              |         |         |         |        |        |
+---------------------+---------+---------+---------+--------+--------+
| [St                 | [Alt    |         |         |        | [Ref.  |
| ressor]{.underline} | ernativ |         |         |        | Quan.] |
|                     | e]{.und |         |         |        | {.unde |
|                     | erline} |         |         |        | rline} |
|                     |         |         |         |        |        |
|                     |         |         |         |        | [I~i(  |
|                     |         |         |         |        | REF)~] |
|                     |         |         |         |        | {.unde |
|                     |         |         |         |        | rline} |
+---------------------+---------+---------+---------+--------+--------+
|                     | *[A     | *[B     | *[C     | *[D]{  |        |
|                     | ]{.unde | ]{.unde | ]{.unde | .under |        |
|                     | rline}* | rline}* | rline}* | line}* |        |
+---------------------+---------+---------+---------+--------+--------+
| CO~2~ (CO~2~        | 208,191 | 227,940 | 210,151 | 2      | 4      |
| equivalents)        |         |         |         | 12,875 | 50,000 |
+---------------------+---------+---------+---------+--------+--------+
| CO                  | 896.56  | 941.76  | 973.91  | 954.46 | 2,000  |
+---------------------+---------+---------+---------+--------+--------+
| NO~x~ (NO~2~)       | 414.68  | 369.54  | 337.75  | 441.02 | 900    |
+---------------------+---------+---------+---------+--------+--------+
| PM-10               | 32.50   | 36.19   | 32.88   | 32.55  | 75     |
+---------------------+---------+---------+---------+--------+--------+
| NMOG (VOC)          | 134.02  | 132.39  | 121.60  | 138.34 | 250    |
+---------------------+---------+---------+---------+--------+--------+
| SO~x~ (SO~2~)       | 228.46  | 239.07  | 217.08  | 223.45 | 400    |
+---------------------+---------+---------+---------+--------+--------+
| 1,3-Butadiene       | 0.18    | 0.11    | 0.14    | 0.20   | 1      |
+---------------------+---------+---------+---------+--------+--------+
| Formaldehyde        | 4.14    | 3.88    | 3.87    | 5.22   | 10     |
+---------------------+---------+---------+---------+--------+--------+
| Toluene             | 2.51    | 2.22    | 2.83    | 2.79   | 5      |
+---------------------+---------+---------+---------+--------+--------+
| Benzene             | 0.90    | 0.78    | 0.99    | 1.00   | 2      |
+---------------------+---------+---------+---------+--------+--------+
| Acetaldehyde        | 0.56    | 0.36    | 0.31    | 0.61   | 2      |
+---------------------+---------+---------+---------+--------+--------+
| Methane             | 403.45  | 802.38  | 572.12  | 496.05 | 1,600  |
+---------------------+---------+---------+---------+--------+--------+
| Methyl t-Butyl      | 1.34    | 1.24    | 1.55    | 1.45   | 3      |
| Ether (MTBE)        |         |         |         |        |        |
+---------------------+---------+---------+---------+--------+--------+
| DPM-10 (diesel      | 1.87    | 0       | 0       | 1.95   | 5      |
| PM-10)              |         |         |         |        |        |
+---------------------+---------+---------+---------+--------+--------+
| TRI emissions       | 8.96    | 9.92    | 8.62    | 8.73   | 20     |
+---------------------+---------+---------+---------+--------+--------+
| Non-renewable       | 1,      | 1,      | 1,      | 1,8    | 4,0    |
| energy use          | 766,630 | 879,210 | 793,773 | 21,412 | 00,000 |
|                     |         |         |         |        |        |
| (units in Mjoules)  |         |         |         |        |        |
+---------------------+---------+---------+---------+--------+--------+
| Fuel use (in        | 11,743  | 12,568  | 12,117  | 12,136 | 25,000 |
| ga                  |         |         |         |        |        |
| soline-equivalents) |         |         |         |        |        |
|                     |         |         |         |        |        |
| (units in gallons)  |         |         |         |        |        |
+---------------------+---------+---------+---------+--------+--------+
| Base-metal ore      | 14,341  | 15,923  | 13,800  | 13,982 | 32,000 |
| depletion           |         |         |         |        |        |
+---------------------+---------+---------+---------+--------+--------+
| Precious-metal ore  | 2,733   | 3,036   | 2,629   | 2,664  | 6,000  |
| depletion           |         |         |         |        |        |
+---------------------+---------+---------+---------+--------+--------+
| RCRA waste          | 318.16  | 350.37  | 308.01  | 312.24 | 700    |
+---------------------+---------+---------+---------+--------+--------+
| Non-recycled solid  | 1,142   | 1,221   | 1,068   | 1,139  | 2,500  |
| waste               |         |         |         |        |        |
+---------------------+---------+---------+---------+--------+--------+
| OPERATING COST (\$) | 87,895  | 98,324  | 86,531  | 88,326 |        |
+---------------------+---------+---------+---------+--------+--------+

<table>
<colgroup>
<col style="width: 12%" />
<col style="width: 1%" />
<col style="width: 9%" />
<col style="width: 0%" />
<col style="width: 4%" />
<col style="width: 10%" />
<col style="width: 4%" />
<col style="width: 6%" />
<col style="width: 8%" />
<col style="width: 4%" />
<col style="width: 9%" />
<col style="width: 6%" />
<col style="width: 8%" />
<col style="width: 3%" />
<col style="width: 11%" />
</colgroup>
<tbody>
<tr class="odd">
<td colspan="15"><strong>Table B3. Reference Values of
D<sub>j(REF)</sub></strong></td>
</tr>
<tr class="even">
<td colspan="4"><u>Human Health End-Point</u></td>
<td colspan="8"><u>Ecological End-Point</u></td>
<td colspan="3"><u>Human Health Damage Potential</u></td>
</tr>
<tr class="odd">
<td>EPS-CDALY<sup>(1,2)</sup></td>
<td colspan="2">Eco-Ind. DALY</td>
<td colspan="3">EPS-NEX<sup>(1)</sup></td>
<td colspan="2">Eco-Ind. PDF</td>
<td colspan="2">EPS-Base Cat. Cap.</td>
<td colspan="2">EPS-Prod. Cap.<sup>(1,2)</sup></td>
<td colspan="2">USES-HTP</td>
<td>EPA-HHHRF</td>
</tr>
<tr class="even">
<td>4.3602</td>
<td colspan="2">0.2371</td>
<td colspan="3">6.2202E-9</td>
<td colspan="2">5558</td>
<td colspan="2">1605</td>
<td colspan="2">-1.9172E+4</td>
<td colspan="2">2.86E+6</td>
<td>27,687</td>
</tr>
<tr class="odd">
<td colspan="15"></td>
</tr>
<tr class="even">
<td colspan="11"><u>Ecological Damage Potential</u></td>
<td colspan="4"><u>Human and Ecological Damage Potential</u></td>
</tr>
<tr class="odd">
<td colspan="2">USES-ETP<sup>(2)</sup></td>
<td colspan="3">EPA-THRF</td>
<td colspan="2">EPA-AHRF</td>
<td colspan="2">Acidification Pot.</td>
<td colspan="2">Eutrophication Pot.</td>
<td colspan="2">POCP</td>
<td colspan="2">GWP</td>
</tr>
<tr class="even">
<td colspan="2">3.15E+4</td>
<td colspan="3">263</td>
<td colspan="2">9,023</td>
<td colspan="2">1,030</td>
<td colspan="2">900</td>
<td colspan="2">765</td>
<td colspan="2">498,203</td>
</tr>
<tr class="odd">
<td colspan="15"><ol type="1">
<li><p>For certain damage indicators, the EPS methodology considers both
damages and beneficial consequences, for example, increased crop
productive capacity due to<br />
carbon fertilization or reduction of global warming due to particulate
emissions. And, the methodology considers these are “credits,” which is
why certain stressor<br />
damage values are indicated as a negative (-) quantity.</p></li>
<li><p>EPS-CDALY, EPS-Productive Capacity (loss), and USES-ETP are
constructed attributes, evaluated as noted in the main body.</p></li>
</ol></td>
</tr>
</tbody>
</table>

**Calculation of "Partial Unit Utility Factors"**

Suppose instead of the above reference basis, we were interested in
optimizing the itinerary of a single vehicle. And, suppose we believed
the "worst case" itinerary for a single vehicle consisted of 200 miles
of transit, 100 minutes of engine idling, and 10 engine starts. We
calculate impacts for this case and use these as the basis for
calculating "unit partial utility factors" and to illustrate the
rescaling of these factors for any system or reference basis. First, we
describe what we mean by a unit partial utility factor.

From Equation B1, it should be seen that the utility value of a
particular damage indicator value (as an attribute) is a linear function
of I~i~, the stressor quantity, and, similarly, from Equation B2 that
unit damage indicator values are the sum of impact-specific unit values.
Moreover, from our equations (in the main text body) for the overall
utility model, all of the component utility functions---u~R~(R),
u~O~(O), u~HD~(HD), u~HP~(HP), u~ED~(ED), u~EP~(EP)---are, likewise,
linear combinations of component (damage indicator or constructed
attribute) values, as these utility functions have been defined in the
main body.

The point is that because of our particular preference assumptions and
the linearity of the LCIA methods utilized, we can determine values of
each of the above six functions on a unit basis---i.e., per mile of
transit, per engine start, and per minute idling---for each vehicle
type. And, the utility value of any itinerary, or sets of itineraries,
can be calculated based on these unit factors. For example, if u~R~(R) =

-x for one mile of transit for vehicle type A, then the utility value
for two miles of transit is --2x---because of the way the factors have
been normalized, i.e., based on a reference quantity. That is, the
factors are *unit* utility factors; and, because each only represents a
single utility component, we refer to them as being *partial unit*
utility factors. Although this requires the determination of values for
72 factors, these must be determined only once; and, the resultant
computational savings through their use is significant.

It should be seen that these factors, and calculated utility values, are
relative to the reference basis. We first calculate unit partial utility
factors for the four vehicle types on the [above basis]{.underline}.
Then, we illustrate how these factors can be rescaled for any system
without recalculation of the individual values. As we explain later, we
only wish to assess decision-maker preferences once; and, we assume that
decision-maker preferences (scaling constants) have already been
assessed for utility functions and consequences based upon the stressor
quantities of Table B2, since preferences are relative to the range of
outcomes considered. More specifically, as we describe later, by
rescaling all utility functions (and reference quantities) by a constant
factor, we can avoid the need to reassess decision-maker preferences.

We first determine stressor quantities representing the "worst case" for
any vehicle type on the above basis. Then, we simply divide the previous
reference quantities by a single factor representing the
[greatest]{.underline} ratio (where a ratio is calculated for each
stressor). The results are provided in Table B4, where the greatest
stressor ratio is seen to be 0.006. And, the new reference quantities
shown in the last column on the Table are the original reference
quantities (Table B3) multiplied by 0.006.

Next, we calculate D~j(REF)~ for all damage indicators based on the new
reference quantities, where

D~j(REF)~ = ∑~i~ I~i(REF)~ D~ij~ = ∑~k~ ∑~i~ I~i(REF)~ D~ijk~, whichever
the case may be, and where values of D~ij~ or D~ijk~ are the unit damage
indicator values reported in the main body. The results are provided in
Table B5. Then, using the unit emissions factors and unit damage
indicator values (both reported in main body), together with the above
reference values, we calculate unit values of I~i~D~ijk~ / D~j(REF)~ for
each vehicle type and activity. Calculated values for one vehicle type
(gasoline-powered "minivan") are reported in Tables B6 through B8 for
illustration.. These values represent the partial unit utility value due
to a particular stressor, i.e., u(I~i~D~ijk~) = - I~i~D~ijk~ /
D~j(REF)~. We then use these values to calculate the unit partial
utility values of interest. That is, because of the commutative and
associative properties of algebra, Equations B1 and B2 can be restated
as u(D~j~) = - ∑~i~ I~i~D~ij~ / D~j(REF)~ = - ∑~k~∑~i~ I~i~D~ijk~ /
D~j(REF)~ = ∑~k~∑~i~ u(I~i~D~ijk~) = - ∑~k~∑~i~ I~i~D~ijk~ / D~j(REF)~.

+---------------------+--------------+-----------+---------+---------+
| **Table B4.         |              |           |         |         |
| Calculation of      |              |           |         |         |
| Scaling Factor For  |              |           |         |         |
| Reference           |              |           |         |         |
| Quantities and      |              |           |         |         |
| Attribute Scales**  |              |           |         |         |
|                     |              |           |         |         |
| (all quantities in  |              |           |         |         |
| kg unless otherwise |              |           |         |         |
| noted)              |              |           |         |         |
+---------------------+--------------+-----------+---------+---------+
| [St                 | [Itinerary   | [Ref.     | [Rati   | [New    |
| ressor]{.underline} | Reference]   | Quan.,    | o]{.und | Ref     |
|                     | {.underline} | I~i(      | erline} | .]{.und |
|                     |              | REF)~]{.u |         | erline} |
|                     | [(Maximum)   | nderline} |         |         |
|                     | Quantity]    |           |         | [Quan,  |
|                     | {.underline} |           |         | I       |
|                     |              |           |         | ~i(REF) |
|                     |              |           |         | ~]{.und |
|                     |              |           |         | erline} |
+---------------------+--------------+-----------+---------+---------+
| CO~2~ (CO~2~        | 589.42       | 450,000   | 0.0013  | 2700    |
| equivalents)        |              |           |         |         |
+---------------------+--------------+-----------+---------+---------+
| CO                  | 5.7970       | 2,000     | 0.0029  | 12      |
+---------------------+--------------+-----------+---------+---------+
| NO~x~ (NO~2~)       | 1.9579       | 900       | 0.0022  | 5.4     |
+---------------------+--------------+-----------+---------+---------+
| PM-10               | 0.0811       | 75        | 0.0011  | 0.45    |
+---------------------+--------------+-----------+---------+---------+
| NMOG (VOC)          | 0.5327       | 250       | 0.0021  | 1.5     |
+---------------------+--------------+-----------+---------+---------+
| SO~x~ (SO~2~)       | 0.5117       | 400       | 0.0013  | 2.4     |
+---------------------+--------------+-----------+---------+---------+
| 1,3-Butadiene       | 0.0016       | 1         | 0.0016  | 0.006   |
+---------------------+--------------+-----------+---------+---------+
| Formaldehyde        | 0.0560       | 10        | 0.0056  | 0.06    |
+---------------------+--------------+-----------+---------+---------+
| Toluene             | 0.0255       | 5         | 0.0051  | 0.03    |
+---------------------+--------------+-----------+---------+---------+
| Benzene             | 0.0089       | 2         | 0.0045  | 0.012   |
+---------------------+--------------+-----------+---------+---------+
| Acetaldehyde        | 0.0050       | 2         | 0.0025  | 0.012   |
+---------------------+--------------+-----------+---------+---------+
| Methane             | 2.7083       | 1,600     | 0.0017  | 9.6     |
+---------------------+--------------+-----------+---------+---------+
| Methyl t-Butyl      | 0.0135       | 3         | 0.0045  | 0.018   |
| Ether (MTBE)        |              |           |         |         |
+---------------------+--------------+-----------+---------+---------+
| DPM-10 (diesel      | 0.0300       | 5         | 0.0060  | 0.03    |
| PM-10)              |              |           |         |         |
+---------------------+--------------+-----------+---------+---------+
| TRI emissions       | 0.0176       | 20        | 0.0009  | 0.12    |
+---------------------+--------------+-----------+---------+---------+
| Non-renewable       | 10,225       | 6,750,000 | 0.0015  | 40,500  |
| energy use          |              |           |         |         |
|                     |              |           |         |         |
| including fuel      |              |           |         |         |
| consumption         |              |           |         |         |
|                     |              |           |         |         |
| (units in Mjoules)  |              |           |         |         |
+---------------------+--------------+-----------+---------+---------+
| Base-metal ore      | 28.75        | 32,000    | 0.0009  | 192     |
| depletion           |              |           |         |         |
+---------------------+--------------+-----------+---------+---------+
| Precious-metal ore  | 5.4805       | 6,000     | 0.0009  | 36      |
| depletion           |              |           |         |         |
+---------------------+--------------+-----------+---------+---------+
| RCRA waste          | 0.6331       | 700       | 0.0009  | 4.2     |
+---------------------+--------------+-----------+---------+---------+
| Non-recycled solid  | 2.7280       | 2,500     | 0.0011  | 15      |
| waste               |              |           |         |         |
+---------------------+--------------+-----------+---------+---------+

+-----------------------+------------------------------+--------------+
| **Table B5. Damage    |                              |              |
| Indicator Reference   |                              |              |
| Values (D~j(REF)~)    |                              |              |
| for Calculation of    |                              |              |
| "Unit Partial Utility |                              |              |
| Values"**             |                              |              |
+-----------------------+------------------------------+--------------+
| [Indicator            | [Indicator]{.underline}      | [D~j(REF)~]  |
| Type]{.underline}     |                              | {.underline} |
+-----------------------+------------------------------+--------------+
| Human Health Damage   | EPS CDALYs                   | 2.615E-02    |
| (End-Point)           |                              |              |
+-----------------------+------------------------------+--------------+
|                       | Eco-Indicator DALYs          | 1.422E-03    |
+-----------------------+------------------------------+--------------+
| Ecological Damage     | EPS -- NEX                   | 3.732E-11    |
| (End-Point)           |                              |              |
+-----------------------+------------------------------+--------------+
|                       | Eco-Indicator PDF            | 3.335E+01    |
+-----------------------+------------------------------+--------------+
|                       | EPS Base Cation Capacity     | 9.630E+00    |
+-----------------------+------------------------------+--------------+
|                       | EPS Productive Capacity Loss | -1.149E+02   |
+-----------------------+------------------------------+--------------+
| Mid-Point (Hazard)    | USES Human Toxicity          | 1.71E+04     |
|                       | Potential (USES-HTP)         |              |
+-----------------------+------------------------------+--------------+
|                       | EPA Human Health Hazard      | 1.661E+02    |
|                       | Ranking Factor               |              |
|                       |                              |              |
|                       | (EPA-HHHRF)                  |              |
+-----------------------+------------------------------+--------------+
|                       | USES Eco-Toxicity Potential  | 1.89E+02     |
|                       | (USES-ETP)                   |              |
+-----------------------+------------------------------+--------------+
|                       | EPA Terrestrial Hazard       | 1.578E+00    |
|                       | Ranking Factor               |              |
|                       |                              |              |
|                       | (EPA-THRF)                   |              |
+-----------------------+------------------------------+--------------+
|                       | EPA Aquatic Hazard Ranking   | 5.414E+01    |
|                       | Factor                       |              |
|                       |                              |              |
|                       | (EPA-AHRF)                   |              |
+-----------------------+------------------------------+--------------+
|                       | Acidification Potential      | 6.189E+00    |
+-----------------------+------------------------------+--------------+
|                       | Eutrophication Potential     | 5.400E+00    |
+-----------------------+------------------------------+--------------+
|                       | Photochemical Oxidant        | 4.593E+00    |
|                       | Creation Potential (POCP)    |              |
+-----------------------+------------------------------+--------------+
|                       | Global Warming Potential     | 2.989E+03    |
|                       | (GWP)                        |              |
+-----------------------+------------------------------+--------------+
| Resource Depletion    | Base Metal Consumption       | 192          |
+-----------------------+------------------------------+--------------+
|                       | Precious Metal Consumption   | 36           |
+-----------------------+------------------------------+--------------+
|                       | Nonrenewable Energy          | 40,500       |
|                       | Consumption                  |              |
+-----------------------+------------------------------+--------------+
| Other Impacts         | TRI Emissions                | 0.12         |
+-----------------------+------------------------------+--------------+
|                       | RCRA Waste Generation        | 4.2          |
+-----------------------+------------------------------+--------------+
|                       | Solid (non-RCRA) Waste       | 15           |
|                       | Generation                   |              |
+-----------------------+------------------------------+--------------+

  ---------------------------- -------------------------- ----------- ----------------------- ----------- ---------------------- ----------- ------------------- -----------
  **Table B6. Values of                                                                                                                                          
  I~i~D~ijk~ / D~j(REF)~ for                                                                                                                                     
  Vehicle Type 1 (Light-Duty,                                                                                                                                    
  Gasoline-Powered "Minivan")                                                                                                                                    
  Per Mile**                                                                                                                                                     

  **[Stressor]{.underline}**   **[Impact Category, LCIA                                                                                                          
                               Indicator, and Value of                                                                                                           
                               I~i~D~ijk~ /                                                                                                                      
                               D~j(REF)~]{.underline}**                                                                                                          

                               [Global                                [Human                                                                 [Species            
                               Warming]{.underline}                   Toxicity]{.underline}                                                  Loss]{.underline}   

                                                                      [Toxic                              [Oxidant                                               
                                                                      Effects]{.underline}                Effects]{.underline}                                   

                               EPS-CDALY                  Eco-In DALY EPS-CDALY               Eco-In DALY EPS-CDALY              Eco-In DALY EPS-NEX             Eco-In PDF

  CO~2~                        4.311E-05                  1.281E-04                                                                          2.928E-04           

  CO                           4.523E-07                              1.666E-09               1.555E-06                                      3.064E-06           

  NO~x~                        -1.806E-07                             5.950E-06               6.817E-05   3.445E-09                          2.186E-06           1.864E-04

  PM-10                        -2.456E-08                             3.068E-06               3.903E-05                                      -4.283E-07          

  (NM)VOC                      1.938E-07                                                                  1.297E-07              2.019E-07   1.656E-06           

  SO~x~                        -5.094E-07                             1.541E-05               4.158E-05                                      -8.537E-06          3.381E-05

  1,3-Butadiene                1.641E-10                              9.935E-10               3.333E-09   1.434E-10              3.945E-10   1.117E-09           

  Formaldehyde                 7.109E-10                              2.655E-09               9.060E-10   3.530E-11              1.015E-09   4.842E-09           

  Toluene                      2.616E-09                                                                  1.276E-09              5.738E-09   2.235E-08           4.318E-11

  Benzene                      1.148E-09                              1.694E-09               3.692E-09   3.164E-10              6.911E-10   7.822E-09           1.732E-10

  Acetaldehyde                 1.308E-10                                                      4.557E-11   7.606E-11              2.869E-10   1.117E-09           

  Methane                      1.061E-08                  2.692E-08                                       2.904E-11              7.831E-11   7.203E-08           

  MTBE                         1.831E-09                                                                  5.782E-10              9.806E-10   1.564E-08           

  DPM-10                                                                                                                                                         

                                                                                                                                                                 

                               EPS Prod. Cap.             Base        USES-HTP                EPA-HHHRF   USES-ETP               EPA-THRF    EPA-AHRF            Acid. Pot.
                                                          Cat.Cap.                                                                                               

                               3.089E-04                  2.986E-04   3.70E-07                2.407E-04   2.36E-08               1.554E-04   2.716E-04           2.985E-04

                                                                                                                                                                 

                               Eutroph. Pot.              POCP        GWP                                                                                        

                               2.015E-04                  2.591E-04   2.949E-04                                                                                  

                                                                                                                                                                 

                               Energy + Fuel Cons.                    Base Metal              Prec. Metal TRI Emis.              RCRA Waste  Solid Waste         

                               3.201E-04                              3.473E-04               3.534E-04   3.500E-04              3.490E-04   3.200E-04           
  ---------------------------- -------------------------- ----------- ----------------------- ----------- ---------------------- ----------- ------------------- -----------

  ---------------------------- -------------------------- ----------- ----------------------- ----------- ---------------------- ----------- ------------------- -----------
  **Table B7. Values of                                                                                                                                          
  I~i~D~ijk~ / D~j(REF)~ for                                                                                                                                     
  Vehicle Type 1 (Light-Duty,                                                                                                                                    
  Gasoline-Powered "Minivan")                                                                                                                                    
  Per Minute Idling**                                                                                                                                            

  **[Stressor]{.underline}**   **[Impact Category, LCIA                                                                                                          
                               Indicator, and Value of                                                                                                           
                               I~i~D~ijk~ /                                                                                                                      
                               D~j(REF)~]{.underline}**                                                                                                          

                               [Global                                [Human                                                                 [Species            
                               Warming]{.underline}                   Toxicity]{.underline}                                                  Loss]{.underline}   

                                                                      [Toxic                              [Oxidant                                               
                                                                      Effects]{.underline}                Effects]{.underline}                                   

                               EPS-CDALY                  Eco-In DALY EPS-CDALY               Eco-In DALY EPS-CDALY              Eco-In DALY EPS-NEX             Eco-In PDF

  CO~2~                        7.656E-06                  2.274E-05                                                                          5.199E-05           

  CO                           9.342E-07                              3.441E-09               3.212E-06                                      6.328E-06           

  NO~x~                        -3.137E-08                             1.034E-06               1.184E-05   5.984E-10                          3.798E-07           3.238E-05

  PM-10                        -1.494E-09                             1.865E-07               2.373E-06                                      -2.605E-08          

  (NM)VOC                      1.326E-07                                                                  8.873E-08              1.381E-07   1.133E-06           

  SO~x~                        -3.198E-08                             9.673E-07               2.611E-06                                      -5.361E-07          2.123E-06

  1,3-Butadiene                9.843E-10                              5.961E-09               2.000E-08   8.604E-10              2.367E-09   6.704E-09           

  Formaldehyde                 4.812E-09                              1.797E-08               6.133E-09   2.389E-10              6.869E-09   3.278E-08           

  Toluene                      1.535E-08                                                                  7.484E-09              3.367E-08   1.311E-07           2.533E-10

  Benzene                      6.726E-09                              9.925E-09               2.162E-08   1.853E-09              4.048E-09   4.581E-08           1.014E-09

  Acetaldehyde                 7.847E-10                                                      2.734E-10   4.564E-10              1.722E-09   6.704E-09           

  Methane                      6.417E-08                  1.628E-07                                       1.756E-10              4.735E-10   4.355E-07           

  MTBE                         7.673E-09                                                                  2.423E-09              4.109E-09   6.555E-08           

  DPM-10                                                                                                                                                         

                                                                                                                                                                 

                               EPS Prod. Cap.             Base        USES-HTP                EPA-HHHRF   USES-ETP               EPA-THRF    EPA-AHRF            Acid. Pot.
                                                          Cat.Cap.                                                                                               

                               5.008E-05                  3.241E-05   1.61E-06                2.387E-04   1.54E-07               1.858E-04   2.111E-04           3.241E-05

                                                                                                                                                                 

                               Eutroph. Pot.              POCP        GWP                                                                                        

                               3.500E-05                  4.193E-04   5.963E-05                                                                                  

                                                                                                                                                                 

                               Energy + Fuel Cons.                    Base Metal              Prec. Metal TRI Emis.              RCRA Waste  Solid Waste         

                               5.820E-05                              2.708E-06               2.111E-06                          1.214E-05                       
  ---------------------------- -------------------------- ----------- ----------------------- ----------- ---------------------- ----------- ------------------- -----------

  ---------------------------- -------------------------- ----------- ----------------------- ----------- ---------------------- ----------- ------------------- -----------
  **Table B8. Values of                                                                                                                                          
  I~i~D~ijk~ / D~j(REF)~ for                                                                                                                                     
  Vehicle Type 1 (Light-Duty,                                                                                                                                    
  Gasoline-Powered "Minivan")                                                                                                                                    
  Per Engine Start**                                                                                                                                             

  **[Stressor]{.underline}**   **[Impact Category, LCIA                                                                                                          
                               Indicator, and Value of                                                                                                           
                               I~i~D~ijk~ /                                                                                                                      
                               D~j(REF)~]{.underline}**                                                                                                          

                               [Global                                [Human                                                                 [Species            
                               Warming]{.underline}                   Toxicity]{.underline}                                                  Loss]{.underline}   

                                                                      [Toxic                              [Oxidant                                               
                                                                      Effects]{.underline}                Effects]{.underline}                                   

                               EPS-CDALY                  Eco-In DALY EPS-CDALY               Eco-In DALY EPS-CDALY              Eco-In DALY EPS-NEX             Eco-In PDF

  CO~2~                        5.185E-06                  1.540E-05                                                                          3.521E-05           

  CO                           4.424E-07                              1.629E-09               1.521E-06                                      2.997E-06           

  NO~x~                        -6.771E-08                             2.231E-06               2.556E-05   1.292E-09                          8.199E-07           6.989E-05

  PM-10                        -9.958E-10                             1.244E-07               1.582E-06                                      -1.736E-08          

  (NM)VOC                      1.054E-07                                                                  7.052E-08              1.098E-07   9.002E-07           

  SO~x~                        -2.164E-08                             6.544E-07               1.766E-06                                      -3.626E-07          1.436E-06

  1,3-Butadiene                7.109E-10                              4.305E-09               1.444E-08   6.214E-10              1.710E-09   4.842E-09           

  Formaldehyde                 3.664E-09                              1.368E-08               4.669E-09   1.819E-10              5.230E-09   2.495E-08           

  Toluene                      1.203E-08                                                                  5.868E-09              2.640E-08   1.028E-07           1.986E-10

  Benzene                      5.304E-09                              7.827E-09               1.705E-08   1.461E-09              3.192E-09   3.613E-08           7.999E-10

  Acetaldehyde                 5.667E-10                                                      1.975E-10   3.296E-10              1.243E-09   4.842E-09           

  Methane                      1.952E-08                  4.951E-08                                       5.341E-11              1.440E-10   1.325E-07           

  MTBE                         6.496E-09                                                                  2.051E-09              3.479E-09   5.550E-08           

  DPM-10                                                                                                                                                         

                                                                                                                                                                 

                               EPS Prod. Cap.             Base        USES-HTP                EPA-HHHRF   USES-ETP               EPA-THRF    EPA-AHRF            Acid. Pot.
                                                          Cat.Cap.                                                                                               

                               3.746E-05                  5.363E-05   1.28E-06                1.504E-04   1.18E-07               1.456E-04   1.673E-04           5.366E-05

                                                                                                                                                                 

                               Eutroph. Pot.              POCP        GWP                                                                                        

                               7.556E-05                  2.167E-04   3.911E-05                                                                                  

                                                                                                                                                                 

                               Energy + Fuel Cons.                    Base Metal              Prec. Metal TRI Emis.              RCRA Waste  Solid Waste         

                               3.985E-05                              1.844E-06               1.444E-06                          8.333E-06                       
  ---------------------------- -------------------------- ----------- ----------------------- ----------- ---------------------- ----------- ------------------- -----------

CALCULATION OF HUMAN HEALTH POTENTIAL DAMAGE (HD) AND ECOLOGICAL
POTENTIAL DAMAGE (ED) PARTIAL UNIT UTILITY FACTORS

Our basic decision model, presented in the main body, combines LCIA
damage indicators (as decision attributes) from multiple LCIA mid-point
and end-point methods, as well as attributes for resource depletion and
"other impacts." The overall objectives hierarchy including attributes
for human health and ecological damage may be seen in Figure 1. It
should be seen that attribute and utility values are first calculated
for human health potential damages (HD), ecological potential damages
(ED), human health damage potential (HP), and ecological damage
potential (EP) and then, ultimately, combined in a single utility value.

For the objectives (and attributes) pertaining to human health and
ecological potential damages, i.e., based on end-point potential damage
indicators,

***u***~Xli~(a~xli~) = - ∑~j~ {I~i~ ∑~k~ \[(D~ijk~)(***b***~Xlijk~)\] /
D~j(REF)~}, ∀ D~j~ ∈ A~Xl~, X ∈ {HD, ED}, (B4)

> ***u***~Xl~(a~Xl~) = ∑~i~ ***u***~Xli~(a~Xli~), (B5)

where A~Xl~ is a decision attribute for Human Health Potential Damages
(HD) or Ecological Potential Damage (ED), a~Xli~ is the value of A~Xl~
for stressor i, and a~Xl~ is the value of A~Xl~ over all stressors. It
should be seen that the first equation can be rearranged as:

***u***~Xli~(a~xli~) = - (***b***~Xlijk~ ){∑~j~ ∑~k~ \[(I~i~ D~ijk~) /
D~j(REF)~\]}, (B6)

where the quantity \[(I~i~ D~ijk~) / D~j(REF)~\] has already been
calculated (Tables B6-B9). (Quantities shown in bold italic typeface are
normal, triangular fuzzy numbers as explained in the main body.) It
should be noted that the quantities ***b***~Xlijk~ are normalized values
such that the minimum value of ***u***~Xl~(a~Xl~) for any a~Xl~ is
"about --1," since the quantity is a fuzzy quantity, and the maximum
value is the degenerate fuzzy number (0, 0, 0).

Utility values for the main sub-objectives, ***u***~HD~(HD) and
***u***~ED~(ED), are calculated as follows, because of our assumed
preference conditions and resultant, additive decomposition form:

***u***~HD~(HD) = ∑~l~ w~Xl~ ***u***~Xl~(a~Xl~), X ∈ HD; ***u***~ED~(ED)
= ∑~l~ w~Xl~ ***u***~Xl~(a~Xl~), X ∈ ED. (B7-8)

In the case of health potential damage, ***u***~HD~(HD) is evaluated
based on a single attribute that, in turn, is evaluated (through
Equation B4) utilizing the LCIA damage indicators Eco-Indicator DALY and
EPS-CDALY (a constructed attribute). For ecological potential damage,
***u***~ED~(ED) is evaluated based on three attributes: EPS Soil Cation
Capacity, EPS Productive Capacity Loss (a constructed attribute), and an
attribute for species loss that is evaluated utilizing Equation B4 and
the LCIA damage indicator of EPS-NEX and Eco-Indicator PDF. Values of
***b***~Xlijk~ and w~Xl~, based on assumed decision-maker preferences,
are provided in Appendix C.

The results, for the reference basis noted earlier (the quantities in
Table B4), are provided in Tables B7 and B8.

![](media/image8.wmf){width="5.571527777777778in"
height="4.209722222222222in"}

> Figure B1. Combined Fundamental and Means-Ends Objectives Network
> Including
>
> Both Mid-Point (Damage Potential) and End-Point (Potential Damage)
>
> Objectives and Attributes

  ------------------- --------------------- -----------------------------------------------
  **Table B7.                               
  Calculated "Unit                          
  Partial Utility                           
  Values" for Human                         
  Health Damage                             
  Potential Attribute                       
  (A~H~)**                                  

  [Veh.               [Basis]{.underline}   [***u***~HD~***(***HD***) =
  Type]{.underline}                         u***(***a***~H1~)]{.underline}

  1                   Mile                  \- (1.066E-4 1.588E-4, 2.320E-4)

                      Minute Idle           \- (1.762E-5, 2.557E-5, 3.692E-5)

                      Engine Start          \- (1.684E-5, 2.503E-5, 3.621E-5)

  2                   Mile                  \- (1.297E-4, 1.933E-4, 2.820E-4)

                      Minute Idle           \- (7.287E-6, 1.101E-5, 1.598E-5)

                      Engine Start          \- (4.938E-6, 7.460E-6, 1.083E-5)

  3                   Mile                  \- (1.615E-4, 2.407E-4, 3.511E-4)

                      Minute Idle           \- (3.159E-5, 4.573E-5, 6.595E-5)

                      Engine Start          \- (3.892E-5, 5.838E-5, 8.400E-5)

  4                   Mile                  \- (8.717E-4, 1.287E-3, 1.966E-3)

                      Minute Idle           \- (2.823E-4, 4.140E-4, 6.398E-4)

                      Engine Start          \- (1.964E-4, 2.875E-4, 4.418E-4)
  ------------------- --------------------- -----------------------------------------------

+---+-----+-------------+--------------+--------------+--------------+
| * |     |             |              |              |              |
| * |     |             |              |              |              |
| T |     |             |              |              |              |
| a |     |             |              |              |              |
| b |     |             |              |              |              |
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| 8 |     |             |              |              |              |
| . |     |             |              |              |              |
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| a |     |             |              |              |              |
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| a |     |             |              |              |              |
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| t |     |             |              |              |              |
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| V |     |             |              |              |              |
| a |     |             |              |              |              |
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| e |     |             |              |              |              |
| s |     |             |              |              |              |
| " |     |             |              |              |              |
| f |     |             |              |              |              |
| o |     |             |              |              |              |
| r |     |             |              |              |              |
| E |     |             |              |              |              |
| c |     |             |              |              |              |
| o |     |             |              |              |              |
| l |     |             |              |              |              |
| o |     |             |              |              |              |
| g |     |             |              |              |              |
| i |     |             |              |              |              |
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| a |     |             |              |              |              |
| l |     |             |              |              |              |
| D |     |             |              |              |              |
| a |     |             |              |              |              |
| m |     |             |              |              |              |
| a |     |             |              |              |              |
| g |     |             |              |              |              |
| e |     |             |              |              |              |
| P |     |             |              |              |              |
| o |     |             |              |              |              |
| t |     |             |              |              |              |
| e |     |             |              |              |              |
| n |     |             |              |              |              |
| t |     |             |              |              |              |
| i |     |             |              |              |              |
| a |     |             |              |              |              |
| l |     |             |              |              |              |
| A |     |             |              |              |              |
| t |     |             |              |              |              |
| t |     |             |              |              |              |
| r |     |             |              |              |              |
| i |     |             |              |              |              |
| b |     |             |              |              |              |
| u |     |             |              |              |              |
| t |     |             |              |              |              |
| e |     |             |              |              |              |
| ( |     |             |              |              |              |
| A |     |             |              |              |              |
| ~ |     |             |              |              |              |
| E |     |             |              |              |              |
| ~ |     |             |              |              |              |
| ) |     |             |              |              |              |
| * |     |             |              |              |              |
| * |     |             |              |              |              |
+---+-----+-------------+--------------+--------------+--------------+
| [ | [   | [***u***(*  | [***u***(    | [***u***(    | [***u        |
| V | Bas | **a***~EI~) | ***a***~E2~) | ***a***~E3~) | ***~ED~(ED)] |
| e | is] | (Species    | (Prod. Cap.  | (Soil Cation | {.underline} |
| h | {.u | Loss)]{     | Loss)]       | Cap.)]       |              |
| . | nde | .underline} | {.underline} | {.underline} |              |
| ] | rli |             |              |              |              |
| { | ne} |             |              |              |              |
| . |     |             |              |              |              |
| u |     |             |              |              |              |
| n |     |             |              |              |              |
| d |     |             |              |              |              |
| e |     |             |              |              |              |
| r |     |             |              |              |              |
| l |     |             |              |              |              |
| i |     |             |              |              |              |
| n |     |             |              |              |              |
| e |     |             |              |              |              |
| } |     |             |              |              |              |
|   |     |             |              |              |              |
| [ |     |             |              |              |              |
| T |     |             |              |              |              |
| y |     |             |              |              |              |
| p |     |             |              |              |              |
| e |     |             |              |              |              |
| ] |     |             |              |              |              |
| { |     |             |              |              |              |
| . |     |             |              |              |              |
| u |     |             |              |              |              |
| n |     |             |              |              |              |
| d |     |             |              |              |              |
| e |     |             |              |              |              |
| r |     |             |              |              |              |
| l |     |             |              |              |              |
| i |     |             |              |              |              |
| n |     |             |              |              |              |
| e |     |             |              |              |              |
| } |     |             |              |              |              |
+---+-----+-------------+--------------+--------------+--------------+
| 1 | M   | \-          | (3.089E-4,   | \-           | \-           |
|   | ile | (3.407E-4,  | 3.089E-4,    | (2.986E-4,   | (1.533E-4,   |
|   |     | 3.724E-4,   | 3.089E-4)    | 2.986E-4,    | 1.720E-4,    |
|   |     | 4.142E-4)   |              | 2.986E-4)    | 1.967E-4)    |
+---+-----+-------------+--------------+--------------+--------------+
|   | Min | \-          | (5.008E-5,   | \-           | \-           |
|   | ute | (6.722E-5,  | 5.008E-5,    | (3.241E-5,   | (2.985E-5,   |
|   | I   | 7.240E-5,   | 5.008E-5)    | 3.241E-5,    | 3.291E-5,    |
|   | dle | 7.930E-5)   |              | 3.241E-5)    | 3.698E-5)    |
+---+-----+-------------+--------------+--------------+--------------+
|   | Eng | \-          | (3.746E-5,   | \-           | \-           |
|   | ine | (5.455E-5,  | 3.746E-5,    | (5.363E-5,   | (2.867E-5,   |
|   | St  | 6.537E-5,   | 3.746E-5)    | 5.363E-5,    | 3.505E-5,    |
|   | art | 7.984E-5)   |              | 5.363E-5)    | 4.359E-5)    |
+---+-----+-------------+--------------+--------------+--------------+
| 2 | M   | \-          | (3.443E-4,   | \-           | \-           |
|   | ile | (4.407E-4,  | 3.443E-4,    | (3.443E-4,   | (2.084E-4,   |
|   |     | 4.883E-4,   | 3.443E-4)    | 3.443E-4,    | 2.365E-4,    |
|   |     | 5.514E-4)   |              | 3.443E-4)    | 2.737E-4)    |
+---+-----+-------------+--------------+--------------+--------------+
|   | Min | \-          | (1.348E-5,   | \-           | \-           |
|   | ute | (1.929E-5,  | 1.348E-5,    | (1.722E-5,   | (9.845E-6,   |
|   | I   | 2.310E-5,   | 1.348E-5)    | 1.722E-5,    | 1.209E-5,    |
|   | dle | 2.819E-5)   |              | 1.722E-5)    | 1.510E-5)    |
+---+-----+-------------+--------------+--------------+--------------+
|   | Eng | \-          | (9.267E-6,   | \-           | \-           |
|   | ine | (1.325E-5,  | 9.267E-6,    | (1.171E-5,   | (6.745E-6,   |
|   | St  | 1.585E-5,   | 9.267E-6)    | 1.171E-5,    | 8.279E-6,    |
|   | art | 1.933E-5)   |              | 1.171E-5)    | 1.033E-5)    |
+---+-----+-------------+--------------+--------------+--------------+
| 3 | M   | \-          | (4.742E-4,   | \-           | \-           |
|   | ile | (5.319E-4,  | 4.742E-4,    | (4.412E-4,   | (2.384E-4,   |
|   |     | 5.942E-4,   | 4.742E-4)    | 4.412E-4,    | 2.752E-4,    |
|   |     | 6.727E-4)   |              | 4.412E-4)    | 3.215E-4)    |
+---+-----+-------------+--------------+--------------+--------------+
|   | Min | \-          | (8.792E-5,   | \-           | \-           |
|   | ute | (1.204E-4,  | 8.792E-5,    | (5.616E-5,   | (5.372E-5,   |
|   | I   | 1.292E-4,   | 8.792E-5)    | 5.616E-5,    | 5.891E-5,    |
|   | dle | 1.410E-4)   |              | 5.616E-5)    | 6.587E-5)    |
+---+-----+-------------+--------------+--------------+--------------+
|   | Eng | \-          | (5.414E-5,   | \-           | \-           |
|   | ine | (1.042E-4,  | 5.414E-5,    | (1.653E-4,   | (6.781E-5,   |
|   | St  | 1.406E-4,   | 5.414E-5)    | 1.653E-4,    | 8.928E-5,    |
|   | art | 1.893E-4)   |              | 1.653E-4)    | 1.180E-4)    |
+---+-----+-------------+--------------+--------------+--------------+
| 4 | M   | \-          | (3.546E-4,   | \-           | \-           |
|   | ile | (4.687E-4,  | 3.546E-4,    | (6.943E-4,   | (2.675E-4,   |
|   |     | 5.919E-4,   | 3.546E-4)    | 6.943E-4,    | 3.402E-4,    |
|   |     | 7.562E-4)   |              | 6.943E-4)    | 4.371E-4)    |
+---+-----+-------------+--------------+--------------+--------------+
|   | Min | \-          | (2.829E-5,   | \-           | \-           |
|   | ute | (3.932E-5,  | 2.829E-5,    | (5.408E-5,   | (2.231E-5,   |
|   | I   | 4.893E-5,   | 2.829E-5)    | 5.408E-5,    | 2.789E-5,    |
|   | dle | 6.174E-5)   |              | 5.408E-5)    | 3.554E-5)    |
+---+-----+-------------+--------------+--------------+--------------+
|   | Eng | \-          | (2.477E-5,   | \-           | \-           |
|   | ine | (4.273E-5,  | 2.477E-5,    | (3.685E-5,   | (2.307E-5,   |
|   | St  | 4.926E-5,   | 2.477E-5)    | 3.685E-5,    | 2.692E-5,    |
|   | art | 5.797E-5)   |              | 3.685E-5)    | 3.206E-5)    |
+---+-----+-------------+--------------+--------------+--------------+

Next, we calculate similar values for the mid-point-based objectives
u~HP~(HP) and u~EP~(EP), Human Health Damage Potential and Ecological
Damage Potential, respectively, including their component attributes.

From our decision model (presented in the main text body), there are two
lowest-level attributes, Human Toxicity Damage Potential (HTDP) and
Eco-Toxicity Damage Potential (ETDP); and, we evaluate these first. From
the decision model:

***g***~Xl~ = ∑~k~ {\[h~lk~ ***e***~lk~ (∑~i~ I~i~DP~ilk~) /
DP~lk(REF)~\] / \[∑~k~ h~lk~ ***e***~lk~\]}, l = 1, 2, ...; X ∈ {HTDP,
ETDP}. (B9)

Here, the attribute HTDP is evaluated using the LCIA damage indicators
(DP~ilk~'s) USES Human Toxic Potential (USES-HTP) and EPA's Human Health
Hazard Ranking Factor (EPA-HHHRF); and the attribute ETDP is evaluated
based on the damage indicators USES Eco-Toxicity Potential (a
constructed attribute, USES-ETP) and EPA's Terrestrial Hazard Ranking
Factor (EPA-THRF) and Aquatic Hazard Ranking Factor (EPA-AHRF).

The quantity ∑~i~ I~i~DP~ilk~) / DP~lk(REF)~ was evaluated previously
(e.g., Tables B6-8); and, assumed values of the scaling constants h~lk~
and ***e***~lk~ are provided in Appendix C. The results, i.e.,
calculated values of HTDP and ETDP are provided in Table B9. Here, we
defuzzify the values as a convenience for use in subsequent calculations
and accept the (small) loss of information that results.

The remaining damage potential attributes, evaluated based upon a single
LCIA unit damage indicator (DP~ijk~), are simply evaluated as:

g~Xl~ = (∑~i~ I~i~DP~ilk~) / DP~lk(REF)~, l = 1, 2, ...; X ∈ {HP, EP}
(B10)

where utility values for damage attributes are calculated as:

u(g~Xl~) = - g~Xl~. (B11)

Finally, values for the decision attributes ***u***~X~(X), X ∈ {HP, EP},
are evaluated as

***u***~X~(X) = ∑~l~ {\[c~Xl~ ***d***~Xl~ u(g~Xl~)\] / \[∑~j~ c~Xj~
***d***~Xj~\]}. (B12)

As before, values of I~i~DP~ilk~) / DP~lk(REF)~ have already been
calculated (e.g., B6-B8); and, assumed values of c~Xl~ ***d***~Xl~ are
provided in Appendix C. Unit partial utility factors for human health
damage potential and ecological damage potential u~HP~(HP) and u~EP~(EP)
are provided in Table B-10.

CALCULATION OF RESOURCE DEPLETION AND OTHER IMPACTS PARTIAL UNIT

UTILITY FACTORS

As noted before, the reference basis (quantities) for Resource Depletion
and Other Impacts attributes are simply the reference quantities shown
in Table B4. Unit partial utility factors for the objectives are
provided in Table B11.

+-----+------+------------------+--------+------------------+--------+
| *   |      |                  |        |                  |        |
| *Ta |      |                  |        |                  |        |
| ble |      |                  |        |                  |        |
| 9.  |      |                  |        |                  |        |
| C   |      |                  |        |                  |        |
| alc |      |                  |        |                  |        |
| ula |      |                  |        |                  |        |
| ted |      |                  |        |                  |        |
| Val |      |                  |        |                  |        |
| ues |      |                  |        |                  |        |
| of  |      |                  |        |                  |        |
| Co  |      |                  |        |                  |        |
| nst |      |                  |        |                  |        |
| ruc |      |                  |        |                  |        |
| ted |      |                  |        |                  |        |
| A   |      |                  |        |                  |        |
| ttr |      |                  |        |                  |        |
| ibu |      |                  |        |                  |        |
| tes |      |                  |        |                  |        |
| Hu  |      |                  |        |                  |        |
| man |      |                  |        |                  |        |
| To  |      |                  |        |                  |        |
| xic |      |                  |        |                  |        |
| ity |      |                  |        |                  |        |
| Dam |      |                  |        |                  |        |
| age |      |                  |        |                  |        |
| Pot |      |                  |        |                  |        |
| ent |      |                  |        |                  |        |
| ial |      |                  |        |                  |        |
| (HT |      |                  |        |                  |        |
| DP) |      |                  |        |                  |        |
| an  |      |                  |        |                  |        |
| d** |      |                  |        |                  |        |
|     |      |                  |        |                  |        |
| **  |      |                  |        |                  |        |
| Eco |      |                  |        |                  |        |
| -To |      |                  |        |                  |        |
| xic |      |                  |        |                  |        |
| ity |      |                  |        |                  |        |
| Dam |      |                  |        |                  |        |
| age |      |                  |        |                  |        |
| Pot |      |                  |        |                  |        |
| ent |      |                  |        |                  |        |
| ial |      |                  |        |                  |        |
| (E  |      |                  |        |                  |        |
| TDP |      |                  |        |                  |        |
| )** |      |                  |        |                  |        |
+-----+------+------------------+--------+------------------+--------+
| [V  | [Ba  | [H               | [Defuz | [E               | [Defuz |
| eh. | sis] | TDP]{.underline} | zified | TDP]{.underline} | zified |
| Ty  | {.un |                  | Value] |                  | Value] |
| pe] | derl |                  | {.unde |                  | {.unde |
| {.u | ine} |                  | rline} |                  | rline} |
| nde |      |                  |        |                  |        |
| rli |      |                  |        |                  |        |
| ne} |      |                  |        |                  |        |
+-----+------+------------------+--------+------------------+--------+
| 1   | Mile | (1.234E-7,       | 8.     | (1.032E-8,       | 2.     |
|     |      | 3.701E-7,        | 065E-5 | 2.356E-8,        | 010E-5 |
|     |      | 2.415E-4)        |        | 6.026E-5)        |        |
+-----+------+------------------+--------+------------------+--------+
|     | Mi   | (5.382E-7,       | 8.     | (6.767E-8,       | 1.     |
|     | nute | 1.615E-6,        | 135E-5 | 1.544E-7,        | 883E-5 |
|     | Idle | 2.419E-4)        |        | 5.628E-5)        |        |
+-----+------+------------------+--------+------------------+--------+
|     | En   | (4.253E-7,       | 5.     | (5.133E-8,       | 1.     |
|     | gine | 1.276E-6,        | 155E-5 | 1.176E-7,        | 484E-5 |
|     | S    | 1.530E-4)        |        | 4.436E-5)        |        |
|     | tart |                  |        |                  |        |
+-----+------+------------------+--------+------------------+--------+
| 2   | Mile | (4.674E-8,       | 9.     | (1.382E-7,       | 3.     |
|     |      | 1.402E-7,        | 753E-5 | 3.153E-7,        | 193E-5 |
|     |      | 2.924E-4)        |        | 9.543E-5)        |        |
+-----+------+------------------+--------+------------------+--------+
|     | Mi   | (3.637E-9,       | 5.     | (7.576E-8,       | 4.     |
|     | nute | 1.091E-8,        | 874E-6 | 1.729E-7,        | 772E-6 |
|     | Idle | 1.761E-5)        |        | 1.407E-5)        |        |
+-----+------+------------------+--------+------------------+--------+
|     | En   | (2.485E-9,       | 4.     | (5.204E-8,       | 3.     |
|     | gine | 7.454E-9,        | 010E-6 | 1.187E-7,        | 263E-6 |
|     | S    | 1.202E-5)        |        | 9.619E-6)        |        |
|     | tart |                  |        |                  |        |
+-----+------+------------------+--------+------------------+--------+
| 3   | Mile | (4.256E-7,       | 1.     | (4.649E-8,       | 3.     |
|     |      | 1.277E-6,        | 473E-4 | 1.061E-7,        | 161E-5 |
|     |      | 4.402E-4)        |        | 9.468E-5)        |        |
+-----+------+------------------+--------+------------------+--------+
|     | Mi   | (8.951E-7,       | 1.     | (1.110E-6,       | 8.     |
|     | nute | 2.685E-6,        | 738E-4 | 2.533E-6,        | 667E-5 |
|     | Idle | 5.178E-4)        |        | 2.564E-4)        |        |
+-----+------+------------------+--------+------------------+--------+
|     | En   | (1.057E-6,       | 1.     | (1.292E-7,       | 3.     |
|     | gine | 3.172E-6,        | 531E-4 | 2.948E-7,        | 473E-5 |
|     | S    | 4.551E-4)        |        | 1.038E-4)        |        |
|     | tart |                  |        |                  |        |
+-----+------+------------------+--------+------------------+--------+
| 4   | Mile | (6.681E-4,       | 2.     | (8.783E-4,       | 2.     |
|     |      | 2.004E-3,        | 415E-3 | 2.004E-3,        | 366E-3 |
|     |      | 4.574E-3)        |        | 4.214E-3)        |        |
+-----+------+------------------+--------+------------------+--------+
|     | Mi   | (2.556E-4,       | 8.     | (3.361E-4,       | 8.     |
|     | nute | 7.668E-4,        | 739E-4 | 7.669E-4,        | 932E-4 |
|     | Idle | 1.599E-3)        |        | 1.577E-3)        |        |
+-----+------+------------------+--------+------------------+--------+
|     | En   | (1.734E-4,       | 7.     | (2.279E-4,       | 6.     |
|     | gine | 5.201E-4,        | 451E-4 | 5.202E-4,        | 059E-4 |
|     | S    | 1.542E-3)        |        | 1.069E-3)        |        |
|     | tart |                  |        |                  |        |
+-----+------+------------------+--------+------------------+--------+

+-----+------+------------------+--------+------------------+--------+
| *   |      |                  |        |                  |        |
| *Ta |      |                  |        |                  |        |
| ble |      |                  |        |                  |        |
| 10. |      |                  |        |                  |        |
| C   |      |                  |        |                  |        |
| alc |      |                  |        |                  |        |
| ula |      |                  |        |                  |        |
| ted |      |                  |        |                  |        |
| Val |      |                  |        |                  |        |
| ues |      |                  |        |                  |        |
| of  |      |                  |        |                  |        |
| A   |      |                  |        |                  |        |
| ttr |      |                  |        |                  |        |
| ibu |      |                  |        |                  |        |
| tes |      |                  |        |                  |        |
| Hu  |      |                  |        |                  |        |
| man |      |                  |        |                  |        |
| Hea |      |                  |        |                  |        |
| lth |      |                  |        |                  |        |
| Dam |      |                  |        |                  |        |
| age |      |                  |        |                  |        |
| Pot |      |                  |        |                  |        |
| ent |      |                  |        |                  |        |
| ial |      |                  |        |                  |        |
| (   |      |                  |        |                  |        |
| G~H |      |                  |        |                  |        |
| P~) |      |                  |        |                  |        |
| an  |      |                  |        |                  |        |
| d** |      |                  |        |                  |        |
|     |      |                  |        |                  |        |
| **E |      |                  |        |                  |        |
| col |      |                  |        |                  |        |
| ogi |      |                  |        |                  |        |
| cal |      |                  |        |                  |        |
| Dam |      |                  |        |                  |        |
| age |      |                  |        |                  |        |
| Pot |      |                  |        |                  |        |
| ent |      |                  |        |                  |        |
| ial |      |                  |        |                  |        |
| (   |      |                  |        |                  |        |
| G~E |      |                  |        |                  |        |
| P~) |      |                  |        |                  |        |
| and |      |                  |        |                  |        |
| Att |      |                  |        |                  |        |
| rib |      |                  |        |                  |        |
| ute |      |                  |        |                  |        |
| "U  |      |                  |        |                  |        |
| nit |      |                  |        |                  |        |
| P   |      |                  |        |                  |        |
| art |      |                  |        |                  |        |
| ial |      |                  |        |                  |        |
| U   |      |                  |        |                  |        |
| til |      |                  |        |                  |        |
| ity |      |                  |        |                  |        |
| Val |      |                  |        |                  |        |
| ues |      |                  |        |                  |        |
| "** |      |                  |        |                  |        |
+-----+------+------------------+--------+------------------+--------+
| [V  | [Ba  | [***g***~        | [u~H   | [***g***~        | [u~E   |
| eh. | sis] | HP~]{.underline} | P~(HP) | EP~]{.underline} | P~(EP) |
| Ty  | {.un |                  | =      |                  | =      |
| pe] | derl |                  | u      |                  | u      |
| {.u | ine} |                  | ~HP~(* |                  | ~EP~(* |
| nde |      |                  | **g*** |                  | **g*** |
| rli |      |                  | ~HP~)] |                  | ~EP~)] |
| ne} |      |                  | {.unde |                  | {.unde |
|     |      |                  | rline} |                  | rline} |
|     |      |                  |        |                  |        |
|     |      |                  | [per   |                  | [per   |
|     |      |                  | Basis  |                  | Basis  |
|     |      |                  | Unit]  |                  | Unit]  |
|     |      |                  | {.unde |                  | {.unde |
|     |      |                  | rline} |                  | rline} |
+-----+------+------------------+--------+------------------+--------+
| 1   | Mile | (6.091E-5,       | \-     | (7.068E-5,       | \-     |
|     |      | 1.748E-4,        | 2.     | 2.277E-4,        | 3.     |
|     |      | 5.905E-4)        | 754E-4 | 7.094E-4)        | 359E-4 |
+-----+------+------------------+--------+------------------+--------+
|     | Mi   | (2.503E-5,       | \-     | (1.541E-5,       | \-     |
|     | nute | 7.181E-5,        | 1.     | 4.966E-5,        | 1.     |
|     | Idle | 3.501E-4)        | 490E-4 | 2.397E-4)        | 016E-4 |
+-----+------+------------------+--------+------------------+--------+
|     | En   | (1.606E-5,       | \-     | (1.030E-5,       | \-     |
|     | gine | 4.609E-5,        | 8.     | 3.318E-5,        | 7.     |
|     | S    | 2.025E-4)        | 822E-5 | 1.732E-4)        | 223E-5 |
|     | tart |                  |        |                  |        |
+-----+------+------------------+--------+------------------+--------+
| 2   | Mile | (7.596E-5,       | \-     | (8.956E-5,       | \-     |
|     |      | 2.179E-4,        | 3.     | 2.886E-4,        | 4.     |
|     |      | 7.134E-4)        | 358E-4 | 8.918E-4)        | 233E-4 |
+-----+------+------------------+--------+------------------+--------+
|     | Mi   | (3.272E-6,       | \-     | (3.615E-6,       | \-     |
|     | nute | 9.388E-6,        | 1.     | 1.165E-5,        | 1.     |
|     | Idle | 2.771E-5)        | 346E-5 | 4.168E-5)        | 898E-5 |
+-----+------+------------------+--------+------------------+--------+
|     | En   | (2.245E-6,       | \-     | (2.486E-6,       | \-     |
|     | gine | 6.441E-6,        | 9.     | 8.009E-6,        | 1.     |
|     | S    | 1.900E-5)        | 230E-6 | 2.856E-5)        | 302E-5 |
|     | tart |                  |        |                  |        |
+-----+------+------------------+--------+------------------+--------+
| 3   | Mile | (9.684E-5,       | \-     | (1.066E-4,       | \-     |
|     |      | 2.779E-4,        | 4.     | 3.436E-4,        | 5.     |
|     |      | 9.557E-4)        | 435E-4 | 1.123E-3)        | 244E-4 |
+-----+------+------------------+--------+------------------+--------+
|     | Mi   | (5.039E-5,       | \-     | (3.173E-5,       | \-     |
|     | nute | 1.446E-4,        | 2.     | 1.023E-4,        | 2.     |
|     | Idle | 6.942E-4)        | 964E-4 | 4.888E-4)        | 076E-4 |
+-----+------+------------------+--------+------------------+--------+
|     | En   | (3.802E-5,       | \-     | (1.503E-5,       | \-     |
|     | gine | 1.091E-4,        | 2.     | 4.842E-5,        | 1.     |
|     | S    | 5.182E-4)        | 218E-4 | 4.249E-4)        | 628E-4 |
|     | tart |                  |        |                  |        |
+-----+------+------------------+--------+------------------+--------+
| 4   | Mile | (5.171E-4,       | \-     | (2.484E-4,       | \-     |
|     |      | 1.484E-3,        | 1.     | 8.003E-4,        | 1.     |
|     |      | 3.227E-3)        | 742E-3 | 2.806E-3)        | 285E-3 |
+-----+------+------------------+--------+------------------+--------+
|     | Mi   | (1.747E-4,       | \-     | (7.378E-5,       | \-     |
|     | nute | 5.013E-4,        | 5.     | 2.377E-4,        | 3.     |
|     | Idle | 1.033E-3)        | 697E-4 | 7.482E-4)        | 532E-4 |
+-----+------+------------------+--------+------------------+--------+
|     | En   | (1.507E-4,       | \-     | (5.377E-5,       | \-     |
|     | gine | 4.325E-4,        | 6.     | 1.733E-4,        | 3.     |
|     | S    | 1.292E-3)        | 251E-4 | 7.796E-4)        | 355E-4 |
|     | tart |                  |        |                  |        |
+-----+------+------------------+--------+------------------+--------+

+--------+-------------+----------------------+------------------------+
| *      |             |                      |                        |
| *Table |             |                      |                        |
| 11.    |             |                      |                        |
| Calc   |             |                      |                        |
| ulated |             |                      |                        |
| "Unit  |             |                      |                        |
| P      |             |                      |                        |
| artial |             |                      |                        |
| U      |             |                      |                        |
| tility |             |                      |                        |
| V      |             |                      |                        |
| alues" |             |                      |                        |
| for    |             |                      |                        |
| Re     |             |                      |                        |
| source |             |                      |                        |
| Dep    |             |                      |                        |
| letion |             |                      |                        |
| (R)**  |             |                      |                        |
|        |             |                      |                        |
| **and  |             |                      |                        |
| other  |             |                      |                        |
| I      |             |                      |                        |
| mpacts |             |                      |                        |
| (O)    |             |                      |                        |
| Attrib |             |                      |                        |
| utes** |             |                      |                        |
+--------+-------------+----------------------+------------------------+
| [Veh.  | [Basis]{    | [                    | [u~O~(O)]{.underline}  |
| Type]  | .underline} | u~R~(R)]{.underline} |                        |
| {.unde |             |                      |                        |
| rline} |             |                      |                        |
+--------+-------------+----------------------+------------------------+
| 1      | Mile        | -3.328E-04           | -3.452E-04             |
+--------+-------------+----------------------+------------------------+
|        | Minute Idle | -3.582E-05           | -3.642E-06             |
+--------+-------------+----------------------+------------------------+
|        | Engine      | -2.453E-05           | -2.500E-06             |
|        | Start       |                      |                        |
+--------+-------------+----------------------+------------------------+
| 2      | Mile        | -3.286E-04           | -3.662E-04             |
+--------+-------------+----------------------+------------------------+
|        | Minute Idle | -2.713E-06           | -2.857E-07             |
+--------+-------------+----------------------+------------------------+
|        | Engine      | -1.884E-06           | -1.429E-07             |
|        | Start       |                      |                        |
+--------+-------------+----------------------+------------------------+
| 3      | Mile        | -4.657E-04           | -3.309E-04             |
+--------+-------------+----------------------+------------------------+
|        | Minute Idle | -6.403E-05           | -1.115E-05             |
+--------+-------------+----------------------+------------------------+
|        | Engine      | -2.867E-05           | -2.929E-06             |
|        | Start       |                      |                        |
+--------+-------------+----------------------+------------------------+
| 4      | Mile        | -3.052E-04           | -3.581E-04             |
+--------+-------------+----------------------+------------------------+
|        | Minute Idle | -4.211E-05           | -3.930E-06             |
+--------+-------------+----------------------+------------------------+
|        | Engine      | -2.861E-05           | -2.643E-06             |
|        | Start       |                      |                        |
+--------+-------------+----------------------+------------------------+

USE OF UNIT PARTIAL UTILITY VALUES

As presented in the main body, the final decision model is given as:

u(alt.) = w~H~ u(H) + w~E~ u(E) + w~R~ u(R) + w~O~ u(O), where (B13)

***u***~H~(H) = w~HD~***u***~HD~(HD) + w~HP~***u***~HP~(HP) +
w~H1~***u***~HD~(HD)***u***~HP~(HP), (B14)

***u***~E~(E) = w~ED~***u***~ED~(ED) + w~EP~***u***~BEP~(EP) +
w~E1~***u***~ED~(ED)***u***~EP~(EP), (B15)

u~R~(R) = ∑~j~ w~Rj~ \[-- (I~j~ / I~j(REF)~)\], I~j~ ∈ {R}, (B16)

u~O~(O) = ∑~j~ w~Oj~ \[-- (I~j~ / I~j(REF)~)\], I~j~ ∈ {O}, (B17)

w~H1~ = 1 -- w~HD~ -- w~HP~, (B18)

w~E1~ = 1 -- w~ED~ -- w~EP~, (B19)

w~H~ + w~E~ + w~R~ + w~O~ = 1, (B20)

where illustrative (assumed) values of all remaining scaling constants
are provided in Appendix C.

Thus, for a given itinerary or sets of itineraries, where the
[total]{.underline} numbers of miles, engines starts, and engine idling
minutes are known [by vehicle type (k)]{.underline},

u~HD~(HD) = ∑~k=1~^K^ (Λ~k~)\[v~HD~(HD)~D,\ k~\] + ∑~k=1~^K^
(∆~k~)\[v~HD~(HD)~I,\ k~\] + ∑~k=1~^K^ (Ω~k~)\[v~HD~(HD)~S,\ k~\] (B21)

u~HP~(HP) = ∑~k=1~^K^ (Λ~k~)\[v~HP~(HP)~D,\ k~\] + ∑~k=1~^K^
(∆~k~)\[v~HP~(HP)~I,\ k~\] + ∑~k=1~^K^ (Ω~k~)\[v~HP~(HP)~S,\ k~\] (B22)

u~ED~(ED) = ∑~k=1~^K^ (Λ~k~)\[v~ED~(ED)~D,\ k~\] + ∑~k=1~^K^
(∆~k~)\[v~ED~(ED)~I,\ k~\] + ∑~k=1~^K^ (Ω~k~)\[v~ED~(ED)~S,\ k~\] (B23)

u~EP~(EP) = ∑~k=1~^K^ (Λ~k~)\[v~EP~(EP)~D,\ k~\] + ∑~k=1~^K^
(∆~k~)\[v~EP~(EP)~I,\ k~\] + ∑~k=1~^K^ (Ω~k~)\[v~EP~(EP)~S,\ k~\] (B24)

u~R~(R) = ∑~k=1~^K^ (Λ~k~)\[v~R~(R)~D,\ k~\] + ∑~k=1~^K^
(∆~k~)\[v~R~(R)~I,\ k~\] + ∑~k=1~^K^ (Ω~k~)\[v~R~(R)~S,\ k~\] (B25)

u~O~(O) = ∑~k=1~^K^ (Λ~k~)\[v~O~(O)~D,\ k~\] + ∑~k=1~^K^
(∆~k~)\[v~O~(O)~I,\ k~\] + ∑~k=1~^K^ (Ω~k~)\[v~O~(O)~S,\ k~\], (B26)

where Λ~k~, ∆~k~, and Ω~k~ denote the distance (miles), engine idling
(minutes), and engine starts (number), respectively, of vehicle type k;
and, the terms v~X~(X)~Y,k~, where X ∈ {HD, HP, ED, EP, R, O} and

Y ∈ {Distance \[D\], Idling \[I\], Starts \[S\]} are the respective unit
partial utility factors (for vehicle type k) described and calculated
previously.

RESCALING OF UNIT PARTIAL UTILITY FACTORS

Finally, it is assumed that decision-maker preferences, i.e., the
preference-based scaling constants presented in Appendix C, have been
assessed for a particular set of outcomes (attribute
values)---specifically, consequences (damage or attribute values)
corresponding to the reference quantities in Table B2. As Keeney (1992)
emphasizes, [these weighting constants are relative to the ranges of
outcomes considered]{.underline}. Given that we have calculated unit
partial utility values for a particular system---set of reference
quantities---we would like to be able to rescale these values for any
system without having to reassess decision-maker preferences (and,
consequently, recalculate the unit utility factors).

This proposition is facilitated by the assumption of linear
single-attribute value (utility) functions over all consequence values.
As depicted in Figure 2, let a and b denote the values of attributes A
and B. Scaling constants provide a measure of the relative importance of
the attributes---relative to their ranges of values. Following the
approach of Keeney (1992) and Keeney and Raiffa (1993), suppose
attribute A were at its "best" value, a, and attribute B were at its
"worst" value, 0. The scaling constant w~1~ is determined by assessing
decision-maker preference indifference, that is, by eliciting the
decision-maker to specify a value b that would compensate for a
reduction in a to zero. That is, the scaling constant w~1~ is the slope
when the points are connected with a line.

![](media/image9.wmf){width="2.595833333333333in"
height="1.9673611111111111in"}

> Figure 2. Illustration of Reference Basis Rescaling

As seen in the Figure, these slopes remain constant if both attributes
are rescaled by a constant factor, due to our preference assumptions.
Similarly, because all of the component utility functions are linear
functions of their respective attributes, the unit partial utility
factors may be rescaled by a constant factor without the need to
reassess decision-maker preferences.

Finally, then, for the actual system that we simulate, we follow the
procedure described herein; namely, we estimate "worst case" impacts and
determine a scaling factor. And, we multiply all of the unit partial
utility factors (Tables B7-B11) by this constant. The actual values used
in our simulation model are provided in Table B12.

  ------------------- --------------------- ------------------- --------------------- --------------------
  **Table B12. Unit                                                                   
  Partial Utility                                                                     
  Factors Used in                                                                     
  Simulation**                                                                        

  [Veh.               [Utility              [Per                [Per Minute Engine    [Per Engine
  Type]{.underline}   Factor]{.underline}   Mile]{.underline}   Idling]{.underline}   Start]{.underline}

  1                   u~HD~(HD)             -(2.665E-6,         -(4.405E-7, 6.393E-7, -(4.210E-7,
                                            3.970E-6, 5.800E-6) 9.230E-7)             6.258E-7, 9.053E-7)

                      u~ED~(ED)             -(3.833E-6,         -(7.463E-7, 8.228E-7, -(7.168E-7,
                                            4.300E-6, 4.918E-6) 9.245E-7)             8.763E-7, 1.090E-6)

                      u~HP~(HP)             -(1.523E-6,         -(6.258E-7, 1.795E-6, -(4.015E-7,
                                            4.370E-6, 1.476E-5) 8.753E-6)             1.152E-6, 5.063E-6)

                      u~EP~(EP)             -(1.767E-6,         -(3.853E-7, 1.242E-6, -(2.575E-7,
                                            5.693E-6, 1.774E-5) 5.993E-6)             8.295E-7, 4.330E-6)

                      u~R~(R)               -8.320E-06          -8.955E-07            -6.133E-07

                      u~O~(O)               -8.630E-06          -9.105E-08            -6.250E-08

  2                   u~HD~(HD)             -(3.243E-6,         -(1.822E-7, 2.753E-7, -(1.235E-7,
                                            4.833E-6, 7.050E-6) 3.995E-7)             1.865E-7, 2.708E-7)

                      u~ED~(ED)             -(5.210E-6,         -(2.461E-7, 3.023E-7, -(1.686E-7,
                                            5.913E-6, 6.843E-6) 3.775E-7)             2.070E-7, 2.583E-7)

                      u~HP~(HP)             -(1.899E-6,         -(8.180E-8, 2.347E-7, -(5.613E-8,
                                            5.448E-6, 1.784E-5) 6.928E-7)             1.610E-7, 4.750E-7)

                      u~EP~(EP)             -(2.239E-6,         -(9.038E-8, 2.913E-7, -(6.215E-8,
                                            7.215E-6, 2.230E-5) 1.042E-6)             2.002E-7, 7.140E-7)

                      u~R~(R)               -8.215E-06          -6.783E-08            -4.710E-08

                      u~O~(O)               -9.155E-06          -7.143E-09            -3.573E-09

  3                   u~HD~(HD)             -(4.038E-6,         -(7.898E-7, 1.143E-6, -(9.730E-7,
                                            6.018E-6, 8.778E-6) 1.649E-6)             1.460E-6, 2.100E-6)

                      u~ED~(ED)             -(5.960E-6,         -(1.343E-6, 1.473E-6, -(1.695E-6,
                                            6.880E-6, 8.038E-6) 1.647E-6)             2.232E-6, 2.95E-6)

                      u~HP~(HP)             -(2.421E-6,         -(1.260E-6, 3.615E-6, -(9.505E-7,
                                            6.948E-6, 2.389E-5) 1.736E-5)             2.728E-6, 1.296E-5)

                      u~EP~(EP)             -(2.665E-6,         -(7.933E-7, 2.558E-6, -(3.758E-7,
                                            8.590E-6, 2.808E-5) 1.222E-5)             1.211E-6, 1.062E-5)

                      u~R~(R)               -1.164E-05          -1.601E-06            -7.168E-07

                      u~O~(O)               -8.273E-06          -2.788E-07            -7.323E-08

  4                   u~HD~(HD)             -(2.179E-5,         -(7.058E-6, 1.035E-5, -(4.910E-6,
                                            3.218E-5, 4.915E-5) 1.600E-5)             7.188E-6, 1.105E-5)

                      u~ED~(ED)             -(6.688E-6,         -(5.578E-7, 6.973E-7, -(5.768E-7,
                                            8.505E-6, 1.093E-5) 8.885E-7)             6.730E-7, 8.015E-7)

                      u~HP~(HP)             -(1.293E-5,         -(4.368E-6, 1.253E-5, -(3.768E-6,
                                            3.710E-5, 8.068E-5) 2.583E-5)             1.081E-5, 3.230E-5)

                      u~EP~(EP)             -(6.210E-6,         -(1.845E-6, 5.943E-6, -(1.344E-6,
                                            2.001E-5, 7.015E-5) 1.871E-5)             4.333E-6, 1.949E-5)

                      u~R~(R)               -7.630E-06          -1.053E-06            -7.153E-07

                      u~O~(O)               -8.953E-06          -9.825E-08            -6.608E-08
  ------------------- --------------------- ------------------- --------------------- --------------------

[APPENDIX C: VALUES OF ASSUMED DECISION-MAKER FACTUAL-]{.underline}

[AND VALUE-BASED SCALING CONSTANTS USED IN CALCULATIONS]{.underline}

**Calculated Values of USES-LCA "Eco-Toxic Potential" Damage Indicator**

+-----------------+-----------------------------+-----------------------+
| **Table C1.     |                             |                       |
| Calculated      |                             |                       |
| USES-LCA        |                             |                       |
| Eco-Toxic**     |                             |                       |
|                 |                             |                       |
| **Damage        |                             |                       |
| Potential (ETP) |                             |                       |
| Indicator       |                             |                       |
| Values          |                             |                       |
| (D~ij~)**       |                             |                       |
+-----------------+-----------------------------+-----------------------+
| [Stress         | [Indicator                  | [Defuzzified          |
| or]{.underline} | Value]{.underline}          | Value]{.underline}    |
+-----------------+-----------------------------+-----------------------+
| (NM)VOC         | (1.4E-4, 2.9E-4, 6.3E-4)    | 3.5E-4                |
+-----------------+-----------------------------+-----------------------+
| 1,3-Butadiene   | (8.2E-7, 1.7E-6, 3.6E-6)    | 2.0E-6                |
+-----------------+-----------------------------+-----------------------+
| Formaldehyde    | (9.0E-1, 2.6E+0, 6.5E+0)    | 3.3E+0                |
+-----------------+-----------------------------+-----------------------+
| Toluene         | (1.8E-4, 3.8E-4, 8.2E-4)    | 4.6E-4                |
+-----------------+-----------------------------+-----------------------+
| Benzene         | (5.9E-4, 1.2E-3, 2.5E-3)    | 1.4E-3                |
+-----------------+-----------------------------+-----------------------+
| Acetaldehyde    | (1.4E-4, 2.9E-4, 6.3E-4)    | 3.5E-4                |
+-----------------+-----------------------------+-----------------------+
| MTBE            | (1.4E-4, 2.9E-4, 6.3E-4)    | 3.5E-4                |
+-----------------+-----------------------------+-----------------------+
| DPM-10          | (2.6E+3, 5.2E+3, 1.1E+4)    | 6.3E+3                |
+-----------------+-----------------------------+-----------------------+

Value- and factual-based judgments are ascribed for a single reference
substance (1,4-dichlorobenzene):

[Compartment]{.underline} [b~k~]{.underline} [w~k~]{.underline}

Terrestrial (0.3, 0.5, 0.7) 0.2

Fresh water aquatic (0.1, 0.3, 0.5) 0.2

Marine aquatic (0.5, 0.7, 0.9) 0.2

Fresh water sediment (0.1, 0.3, 0.5) 0.2

Marine sediment (0.5, 0.7, 0.9) 0.2

Values of ETP~i~ are calculated as:

***ETP***~i~ = ∑~k~ \[(w~k~ ***b***~k~ D~ik~) / (∑~k~ w~k~***b***~k~)\],

where D~ik~ is the compartment- and substance-specific ecological
toxicity indicator value.

**Assumed Weighting Constants for Calculation of Human Health and
Ecological Potential Damage, u~HD~(HD) and u~ED~(ED)**

  ------------------------ ------------------------- ------------------- ------------------------- ------------------- ------------------------- ------------------- ------------------------- ------------------
  **Table C2. Normalized                                                                                                                                                                       
  Values of *b*~Xlijk~**                                                                                                                                                                       

  [Stressor]{.underline}   **[Human Health Damage                                                                                                                    **[Ecological Damage      
                           Category]{.underline}**                                                                                                                   Category]{.underline}**   

                           GLOBAL WARMING                                HUMAN TOXICITY                                OXIDANT FORMATION                             SPECIES LOSS              

                           [EPS-CDALY]{.underline}   [Eco-In.            [EPS-CDALY]{.underline}   [Eco-In.            [EPS-CDALY]{.underline}   [Eco-In.            [EPS-NEX]{.underline}     [Eco-In.
                                                     DALY]{.underline}                             DALY]{.underline}                             DALY]{.underline}                             PDF]{.underline}

  CO~2~                    (.38, .55, .78)           (.31, .45, .67)                                                                                                 (1, 1, 1)                 (0, 0, 0)

  CO                       (1, 1, 1)                 (0, 0, 0)           (.38, .55, .78)           (.31, .45, .67)                                                   (1, 1, 1)                 (0, 0, 0)

  NO~x~                    (1, 1, 1)                 (0, 0, 0)           (.40, .58, .90)           (.27, .42, .60)     (1, 1, 1)                 (0, 0, 0)           (.43, .64, 1.0)           (.21, .36, .56)

  PM-10                    (1, 1, 1)                 (0, 0, 0)           (.40, .58, .90)           (.27, .42, .60)                                                   (1, 1, 1)                 (0, 0, 0)

  (NM)VOC                  (1, 1, 1)                 (0, 0, 0)                                                         (.33, .50, .75)           (.33, .50, .75)     (1, 1, 1)                 (0, 0, 0)

  SO~x~                    (1, 1, 1)                 (0, 0, 0)           (.40, .58, .90)           (.27, .42, .60)                                                   (.43, .64, 1.0)           (.21, .36, .56)

  1,3-Butadiene            (1, 1, 1)                 (0, 0, 0)           (.21, .36, .56)           (.43, .64, 1.0)     (.21, .36, .56)           (.43, .64, 1.0)     (1, 1, 1)                 (0, 0, 0)

  Formaldehyde             (1, 1, 1)                 (0, 0, 0)           (.21, .36, .56)           (.43, .64, 1.0)     (.21, .36, .56)           (.43, .64, 1.0)     (1, 1, 1)                 (0, 0, 0)

  Toluene                  (1, 1, 1)                 (0, 0, 0)                                                         (.21, .36, .56)           (.43, .64, 1.0)     (.40, .58, .90)           (.27, .42, .60)

  Benzene                  (1, 1, 1)                 (0, 0, 0)           (.31, .45, .67)           (.38, ,55, .78)     (.31, .45, .67)           (.38, ,55, .78)     (.40, .58, .90)           (.27, .42, .60)

  Acetaldehyde             (1, 1, 1)                 (0, 0, 0)           (0, 0, 0)                 (1, 1, 1)           (.31, .45, .67)           (.38, ,55, .78)     (1, 1, 1)                 (0, 0, 0)

  CH4                      (.38, .55, .78)           (.31, .45, .67)                                                   (.40, .58, .90)           (.27, .42, .60)     (1, 1, 1)                 (0, 0, 0)

  MTBE                     (1, 1, 1)                 (0, 0, 0)                                                         (.21, .36, .56)           (.43, .64, 1.0)     (1, 1, 1)                 (0, 0, 0)

  DPM-10                   (1, 1, 1)                 (0, 0, 0)           (.43, .64, 1.0)           (.21, .36, .56)     (0, 0, 0)                 (1, 1, 1)           (.45, .67, 1.17)          (.09, .33, .67)
  ------------------------ ------------------------- ------------------- ------------------------- ------------------- ------------------------- ------------------- ------------------------- ------------------

**Assumed Weighing Constants for Calculation of Human Health and
Ecological Damage Potential**

+----------------------+------------------------------+-----+--------+
| **Table C3. Values   |                              |     |        |
| of Value- and        |                              |     |        |
| Factual-Based        |                              |     |        |
| Scaling Constants    |                              |     |        |
| c~Xj~, *d*~Xj~,      |                              |     |        |
| *e*~Xjk~, and        |                              |     |        |
| h~Xjk~**             |                              |     |        |
+----------------------+------------------------------+-----+--------+
| [Attribute           | [Component Attribute         | [Sc | [      |
| (Obj                 | or]{.underline}              | ali | Value] |
| ective)]{.underline} |                              | ng] | {.unde |
|                      | [Constituent LCIA            | {.u | rline} |
|                      | Indicator]{.underline}       | nde |        |
|                      |                              | rli |        |
|                      |                              | ne} |        |
|                      |                              |     |        |
|                      |                              | [   |        |
|                      |                              | Con |        |
|                      |                              | sta |        |
|                      |                              | nt] |        |
|                      |                              | {.u |        |
|                      |                              | nde |        |
|                      |                              | rli |        |
|                      |                              | ne} |        |
+----------------------+------------------------------+-----+--------+
| Human Health Damage  | Global Warming Damage        | c~  | 0.47   |
| Potential (HP)       | Potential (GWDP-H)           | H1~ |        |
+----------------------+------------------------------+-----+--------+
|                      |                              | **  | (0.25, |
|                      |                              | *d* | 0.5,   |
|                      |                              | **~ | 0.75)  |
|                      |                              | H1~ |        |
+----------------------+------------------------------+-----+--------+
|                      | Human Toxicity Damage        | c~  | 0.30   |
|                      | Potential (HTDP)             | H2~ |        |
+----------------------+------------------------------+-----+--------+
|                      |                              | **  | (0.5,  |
|                      |                              | *d* | 1, 1)  |
|                      |                              | **~ |        |
|                      |                              | H2~ |        |
+----------------------+------------------------------+-----+--------+
|                      | Oxidant Creation Damage      | c~  | 0.23   |
|                      | Potential (OCDP-H)           | H3~ |        |
+----------------------+------------------------------+-----+--------+
|                      |                              | **  | (0, 0, |
|                      |                              | *d* | 0.5)   |
|                      |                              | **~ |        |
|                      |                              | H3~ |        |
+----------------------+------------------------------+-----+--------+
| Ecological Damage    | Global Warming Damage        | c~  | .34    |
| Potential (EP)       | Potential (GWDP-E)           | E1~ |        |
+----------------------+------------------------------+-----+--------+
|                      |                              | **  | (0.5,  |
|                      |                              | *d* | 1, 1)  |
|                      |                              | **~ |        |
|                      |                              | E1~ |        |
+----------------------+------------------------------+-----+--------+
|                      | Eco-Toxicity Damage          | c~  | 0.22   |
|                      | Potential (ETDP)             | E2~ |        |
+----------------------+------------------------------+-----+--------+
|                      |                              | **  | (0.25, |
|                      |                              | *d* | 0.50,  |
|                      |                              | **~ | 0.75)  |
|                      |                              | E2~ |        |
+----------------------+------------------------------+-----+--------+
|                      | Oxidant Creation Damage      | c~  | 0.12   |
|                      | Potential (OCDP-E)           | E3~ |        |
+----------------------+------------------------------+-----+--------+
|                      |                              | **  | (0, 0, |
|                      |                              | *d* | 0.5)   |
|                      |                              | **~ |        |
|                      |                              | E3~ |        |
+----------------------+------------------------------+-----+--------+
|                      | Acidification Damage         | c~  | 0.17   |
|                      | Potential (ADP)              | E4~ |        |
+----------------------+------------------------------+-----+--------+
|                      |                              | **  | (0, 0, |
|                      |                              | *d* | 0.5)   |
|                      |                              | **~ |        |
|                      |                              | E4~ |        |
+----------------------+------------------------------+-----+--------+
|                      | Eutrophication Damage        | c~  | 0.15   |
|                      | Potential (EDP)              | E5~ |        |
+----------------------+------------------------------+-----+--------+
|                      |                              | **  | (0, 0, |
|                      |                              | *d* | 0.5)   |
|                      |                              | **~ |        |
|                      |                              | E5~ |        |
+----------------------+------------------------------+-----+--------+
| Human Toxicity       | USES-Human Toxicity          | h~H | 0.50   |
| Damage Potential     | Potential (USES-HTP)         | 21~ |        |
| (HTDP)               |                              |     |        |
+----------------------+------------------------------+-----+--------+
|                      |                              | *** | (0.5,  |
|                      |                              | e** | 1, 1)  |
|                      |                              | *~H |        |
|                      |                              | 21~ |        |
+----------------------+------------------------------+-----+--------+
|                      | USEPA Human Health Hazard    | h~H | 0.50   |
|                      | Ranking Factor (EPA-HHHRF)   | 22~ |        |
+----------------------+------------------------------+-----+--------+
|                      |                              | *** | (0, 0, |
|                      |                              | e** | 0.5)   |
|                      |                              | *~H |        |
|                      |                              | 22~ |        |
+----------------------+------------------------------+-----+--------+
| Eco-Toxicity Damage  | USES Eco-Toxicity Potential  | h~E | 0.78   |
| Potential (ETDP)     | (USES-ETP) (Constructed      | 21~ |        |
|                      | Attribute)                   |     |        |
+----------------------+------------------------------+-----+--------+
|                      |                              | *** | (0.5,  |
|                      |                              | e** | 1, 1)  |
|                      |                              | *~E |        |
|                      |                              | 21~ |        |
+----------------------+------------------------------+-----+--------+
|                      | USEPA Terrestrial Hazard     | h~E | 0.11   |
|                      | Ranking Factor (EPA-THRF)    | 22~ |        |
+----------------------+------------------------------+-----+--------+
|                      |                              | *** | (0, 0, |
|                      |                              | e** | 0,5)   |
|                      |                              | *~E |        |
|                      |                              | 22~ |        |
+----------------------+------------------------------+-----+--------+
|                      | USEPA Aquatic Hazard Ranking | h~E | 0.11   |
|                      | Factor (EPA-AHRF)            | 23~ |        |
+----------------------+------------------------------+-----+--------+
|                      |                              | *** | (0, 0, |
|                      |                              | e** | 0.5)   |
|                      |                              | *~E |        |
|                      |                              | 23~ |        |
+----------------------+------------------------------+-----+--------+

**Assumed Weighting Constants for Calculation of Ecological Potential
Damage, Human Health Damage,**

**Ecological Damage, Resource Depletion, Other Impacts, and
Highest-Level Utility Function**

+----------------------+-----------------------------+------+--------+
| **Table C4. Values   |                             |      |        |
| of Remaining,        |                             |      |        |
| Assumed              |                             |      |        |
| (Hypothetical)       |                             |      |        |
| Value-Based Scaling  |                             |      |        |
| Constants**          |                             |      |        |
+----------------------+-----------------------------+------+--------+
| [Utility Function    | [Component                  | [Sca | [      |
| (Att                 | Attribute]{.underline}      | ling | Value] |
| ribute)]{.underline} |                             | C    | {.unde |
|                      |                             | onst | rline} |
|                      |                             | ant] |        |
|                      |                             | {.un |        |
|                      |                             | derl |        |
|                      |                             | ine} |        |
+----------------------+-----------------------------+------+--------+
| Ecological Potential | Species Loss                | w    | 0.59   |
| Damage (ED)          |                             | ~E1~ |        |
+----------------------+-----------------------------+------+--------+
|                      | Productive Capacity Loss    | w    | 0.28   |
|                      |                             | ~E2~ |        |
+----------------------+-----------------------------+------+--------+
|                      | Soil Base Cation Capacity   | w    | 0.13   |
|                      | Loss                        | ~E3~ |        |
+----------------------+-----------------------------+------+--------+
| Resource Depletion   | Base Metal Depletion        | w    | 0.10   |
|                      |                             | ~R1~ |        |
+----------------------+-----------------------------+------+--------+
|                      | Precious Metal Depletion    | w    | 0.30   |
|                      |                             | ~R2~ |        |
+----------------------+-----------------------------+------+--------+
|                      | Non-Renewable Energy        | w    | 0.60   |
|                      | Consumption                 | ~R3~ |        |
+----------------------+-----------------------------+------+--------+
| Other Impacts        | TRI Emissions               | w    | 0.55   |
|                      |                             | ~O1~ |        |
+----------------------+-----------------------------+------+--------+
|                      | Solid (non-RCRA) Waste      | w    | 0.15   |
|                      | Generation                  | ~O2~ |        |
+----------------------+-----------------------------+------+--------+
|                      | RCRA Waste Generation       | w    | 0.30   |
|                      |                             | ~O3~ |        |
+----------------------+-----------------------------+------+--------+
| Human Health Damage  | Human Health Potential      | w~   | 0.88   |
| (H)                  | Damage (HD)                 | H11~ |        |
+----------------------+-----------------------------+------+--------+
|                      | Human Health Damage         | w~   | 0.34   |
|                      | Potential (HP)              | H12~ |        |
+----------------------+-----------------------------+------+--------+
| Ecological Damage    | Ecological Potential Damage | w~   | 0..84  |
| (E)                  | (ED)                        | E11~ |        |
+----------------------+-----------------------------+------+--------+
|                      | Ecological Damage Potential | w~   | 0.49   |
|                      | (EP)                        | E12~ |        |
+----------------------+-----------------------------+------+--------+
| Environmental Impact | Human Health Damage (H)     | w~H~ | 0.47   |
|                      |                             |      |        |
| (Highest-level       |                             |      |        |
| objective)           |                             |      |        |
+----------------------+-----------------------------+------+--------+
|                      | Ecological Damage (E)       | w~E~ | 0.23   |
+----------------------+-----------------------------+------+--------+
|                      | Resource Depletion (R)      | w~R~ | 0.17   |
+----------------------+-----------------------------+------+--------+
|                      | Other Impacts (O)           | w~O~ | 0.13   |
+----------------------+-----------------------------+------+--------+

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