EPA-AA-SDSB-84-01

                   Technical  Report
                The  Feasibility,  Cost,

              and Cost Effectiveness of

                Onboard Vapor Control
                  Glenn W.  Passavant
                      March  1984
                        NOTICE

Technical Reports  do not  necessarily represent  final  EPA
decisions  or  positions.    They  are  intended  to  present
technical  analysis   of   issues   using   data  which   are
currently, available.   The  purpose  in  the release  of  such
reports  is   to   facilitate  the   exchange   of-'  technical
information   and   to   inform   the  public   of   .technical
developments  which may  form  the   basis  for  a   final  EPA
decision, position or regulatory action.

       Standards Development and  Support  Branch
         Emission Control Technology Division
               Office  of Mobile Sources
             Office of Air  and Radiation
        U.  S. Environmental Protection Agency

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                       Table of Contents

                                                            Page
I.    Introduction 	  1

II.   Technological Feasibility  	  1

III.  In-Use Performance of Onboard Systems  	  7

IV.   In-Use Emission Control Effectiveness  	 10

V.    Costs of Onboard Vapor Recovery  	 ....13

VI.   Cost Effectiveness	21

VII.  Leadtime Requirements  	 24

VIII. Onboard Control Versus Time  	 27

IX.   Conclusions	33

References	35

Appendix A: "Recommendation    on    Feasibility    for    Onboard
            Refueling Loss Control," February 1980.

Appendix B: "LDV and LOT Operation and Usage Characteristics"

Appendix C: Tables  from  "Manufacturing  Costs  and  Automotive
            Retail Price  Equivalent  of  Onboard Vapor  Recovery
            System for Gasoline - Filling Vapors"

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I.   Introduction

     This   report  updates   the  previous   analysis   of  the
technological feasibility,  in-use  effectiveness,  cost, and cost
effectiveness   of  an   onboard   vapor   recovery   system  for
controlling  refueling   emissions   from  gasoline-fueled  motor
vehicles.   The   last  report  in  this  area   is  dated  February
1980.   In  that  report  it  was  concluded   that  onboard  vapor
recovery was feasible for  light-duty vehicles (LDVs).  However,
some question remained about  the  feasibility for  other types of
gasoline-fueled  motor  vehicles  and   the  cost effectiveness  of
controlling  refueling  vapors  through  the  use   of  an  onboard
system.

     Therefore,    this   report  addresses  the   feasibility  of
control  for other  gasoline-fueled  motor vehicles  (light-duty
trucks  (LDTs) and heavy-duty gasoline-fueled vehicles  (HDGVs))
in addition to  LDVs, and also examines  those factors related to
cost effectiveness.  The feasibility  is  examined  for HDGVs, but
the  cost and emission   reduction  impacts  are not determined.
However, cost-effectiveness  values similar  to  those calculated
for LDVs and LDTs would be expected.

     This report  begins  with a discussion of the  technological
feasibility of  onboard control, and  this will be  followed by _a
calculation  of   the in-use   effectiveness   of  onboard  control
systems.  After reviewing and  updating  the  previous estimates
of the  costs  of control,  the cost effectiveness of an onboard
strategy will be calculated.   In  addition,   a fifth section of
the  report  estimates   the   leadtime  necessary    to  implement
onboard  controls,  and   the   last  section   estimates  the  time
required  for  an  onboard   strategy   to   achieve  control  of  a
substantial portion  of   in-use  refueling emissions.   A summary
of the overall conclusions closes the report.

II.  Technological Feasibility

     A.    Introduction

     The bulk of the  experimental work  in  the area of onboard
vapor  recovery  has  been  performed  by  the   American  Petroleum
Institute   (API)  and  their  contractors,   Exxon,   Mobil,  and
Atlantic   Richfield   (ARCO).    They   completed   a   vehicle
demonstration of  onboard vapor  recovery  in  October of 1978[1].
The  results  of  that   study  strongly   suggest    that  onboard
controls  are  feasible  and  effective  in controlling  gasoline
refueling losses from low-   to  mid-mileage   LDVs,  with only  a
negligible impact on a vehicle's ability  to  comply  with current
exhaust or evaporative  emission  standards.

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     Following  the  release  of  the  API  work  in  1978,  EPA
solicited comments  from the  motor  vehicle  industry concerning
the cost  and  technological feasibility of  onboard  controls for
LDVs  and  LDTs.   These  comments  were   incorporated  in  EPA's
analysis  of  the  API  vehicle  demonstration  program     (This
report   is   presented   in  Appendix   A,   "Recommendation  on
Feasibility for Onboard Refueling Loss  Control,"  dated February
1980.)[2]   The   judgment   that   onboard  vapor   recovery  is
technologically feasible for  gasoline-fueled motor  vehicles is
based  largely  on  this  analysis  of  the  API  work  and  the
technological  feasibility  comments  submitted   by  the  motor
vehicle  industry.   In  the  remainder  of  this  section,  the
information leading  to the conclusion  that onboard  control is
feasible  for  LDVs   is   reviewed,   and   the   feasibility  of
controlling LDTs  and HDGVs  is discussed.

     B.     Review of LDV Feasibility

     1.     New System Performance

     The onboard  contol  effectiveness  of  new systems  is based
on the results of  the API  vehicle demonstration  program.  This
program consisted of  SHED  tests of the entire  system minus the
filipipe seal  (the  fillpipe was  plugged)  and bench  SHED tests
of  the  ARCO  rotary  fillpipe   seal.   These  tests   showed  that
refueling emission control efficiency ranged from  98.2  to 99.3
percent for both total HC  and  benzene,  with  an  average value of
98.9  percent. [3]   Based   on  these  results, a  control  system
efficiency  of   at   least   98  percent   is   judged   to   be
representative  of   potential   new   vehicle  control   for  the
canister/modified fillpipe  and  seal system  evaluated by  API.  A
diagram of  the system evaluated by API  is given in  Figure A-l
of Appendix A.

     2.     Mechanical Durability

     EPA's  1980 report  summarized the ARCO  API  durability data
on the nozzle/fillpipe  seal effectiveness.  These  data  were of
necessity   derived   from   an   accelerated   test   program,  and
therefore concerns about seal durability  over time  could not be
addressed.  After completion of the original  work  for API, ARCO
installed a fillpipe  cone  seal (Figure  A-6 of Appendix  A)  in a
company vehicle and monitored seal effectiveness  over 26 months
and approximately 54,000 road miles near  their  Harvey, Illinois
facility.   During  the 26 months,   the  seal  was  exposed  to
environmental    extremes   representative   of   most   of   the
continential United States.

     ARCO tested  the  seal effectiveness  by measuring   the  HC
concentration  at  the  fillpipe/nozzle  interface  each time  the

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                              -3-
vehicle   was   refueled.    At  periodic   intervals   the  seal
effectiveness was  checked by measuring  the leak  rate past the
seal using a specially  designed nozzle  to pressurize the system
with  nitrogen.   The  pressure  check  tests  were  performed  at
system pressures corresponding  to 5, 10,  15, and  20  inches of
water, at which the seal  effectiveness  was still 99 percent.  A
pressure  of  4-5  inches of  water  is  typical  for  a normal  fuel
fill.  Therefore,  the  ARCO  data  indicate  excellent   sealing
capability over  time.  Overall,  seal effectiveness  was better
than 99 percent after two years of  service using unleaded fuel,
and 99 percent effective  after an additional  11,000 miles using
a high concentration  (20 percent)  methanol/gasoline blend.[4]

     The  ARCO  in-use  data   suggest  that  effective,  durable,
low-cost  fillpipe  seals  (rotary  seals  or  cone  seals)   are
feasible  for LDVs  for  in-use service to at  least 50,000 miles
over a  two-year  period.  The  available data  is not conclusive
as  to  which  type   of  seal   is  preferable.    The  important
question, which  has  not  been fully  addressed,   is  whether  the
fillpipe seal will be effective throughout the  full useful life
of  a  vehicle.    Remaining  effective  implies   no  significant
deterioration, contraction,  or  expansion  problems under normal
environmental conditions  such  that  the  seal  fails to achieve-a
leak-free connection with the fuel  nozzle,  or the nozzle cannot
be  inserted  through the  fillpipe seal  at  all.    At  this time,
durability data do  not  exist out  to  the  full  average life  of a
typical  LDV,  100,000 miles   (10  years),  or  120,000  miles  (11
years)   for  LDTs.   However,  the  durability  data up  to 65,000
miles  indicate  no  reason why  the  seal  would   not  continue  to
perform  over  its  full  life.   Given this  durability  data  to
65,000 miles, the relative simplicity of the  system design, and
the  nature   of   its  use,  it  is  reasonable  to  project  that
full-life performance should occur.

     3.    Effect on Gaseous and Evaporative Emissions

     The  work conducted  by API  indicated  that purging  the
refueling  vapors   had   no   significant   effect   on   exhaust
emissions.  However,  it should be cautioned  that the tests were
conducted on  1978  and  earlier model year  vehicles  which  had
emission  levels  higher  than  today's  new vehicles.   Also,  test
procedures for measuring  refueling  emissions have not yet  been
fully  developed  and  it  should  be  recognized   that  the  test
procedure requirements  for  purging  the  vapor  recovery canister
could impact exhaust  and  evaporative  emissions.   However, it is
expected  that  through  proper  design  of  the   onboard   control
systems   (taking    into    consideration    appropriate    purge
requirements),  increases  in  exhaust  or  evaporative  emissions
can be avoided.

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                              -4-
     C.    Feasibility for LDTs and HDGVs

     Even   though   the   API   feasibility   evaluation  project
involved  only  LDVs,  onboard  control   technology  should  be
directly and fully adaptable  to LDTs.  LDV and LDT fuel systems
are  practically identical,  and both  use  similar hardware  to
comply with  the 2.0  g/test evaporative  emission standard.  The
primary difference between LDVs and  LDTs  is  in  the  fuel tank
specifications.  Analysis  of  1984  certification information and
discussions  with  the manufacturers  indicate  that, on average,
LDT fuel tanks  are about  25 percent  larger than LDV fuel tanks,
and  about  20 percent  of  LDTs  use dual  fuel  tanks.    A larger
volume fuel  tank would require  more charcoal in the canister to
accommodate  the  increased volume  of refueling vapors, and LDTs
using  dual  fuel tanks  may require a  separate  onboard control
system  for  each tank.   However,   neither  of  these differences
has  an  effect  on  the   conceptual   design  or   technological
feasibility of an onboard control system.

     The  above  considerations  apply  equally  to  many of  the
smaller HDGVs  (those less than  1-4,000 Ibs  gross vehicle weight
(GVW)).   Approximately  65 to  70  percent  of  all  HDGVs  are
essentially  LDT derivatives.[5]   These  HDGVs  are essentially
the same as  their  parent  LDTs in their  basic  chassis, body and
powertrain  designs,  but   have  been  classified   as  HDGVs  for
purposes of  emission  control because  their GVW,  frontal  area,
or  curb  weight  are  just above  the  LDT/HDGV  cut-off points.
Although these  characteristics  would  have an  effect  on exhaust
emissions, they  would  have no  effect  on the  ability  to comply
with an onboard vapor  recovery requirement.   The  key  parameter
which  influences  feasibility  is  fuel  tank  volume.    Most  of
these  smaller HDGVs have  fuel tank sizes similar to the heavier
LDTs,  so  the  onboard  systems  used  on  LDTs  could be applied
directly to  the smaller  HDGVs.   For  those  smaller HDGVs with
larger  fuel  tanks, larger  charcoal canister  volumes  could  be
utilized.

     The application of  an onboard control  requirement to many
of the larger,  heavier  GVW HDGVs  is somewhat  more complicated.
HDGVs  in  this  group  are  sold in  many different configurations
with different  fuel  tank  sizes and locations.   Also,  many  of
these  HDGVs  are sold  initially as  incomplete vehicles by  the
primary manufacturer to  a secondary manufacturer.  In the most
common case, the primary  manufacturer  produces  the chassis and
the secondary manufacturer  adds a payload-carrying device.   In

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some cases,  the overall vehicle  fuel capacity  is  increased by
the  secondary manufacturer.   In  these  cases  a problem might
arise  because the  primary  manufacturer  would  have  to certify
the onboard control  system  before it was sold  to the consumer,
but  the  secondary  manufacturer  could  affect the  integrity of
the  system.    Many  of   these  problems   are  similar  to  those
encountered   and   resolved   in  the   recent   HDGV  evaporative
emissions  final   rule,   which   suggests   that  implementation
problems  can   be   solved.   Also,  for  the  foreseeable  future,
these heavier  GVW  HDGVs  will be using leaded fuel  and will not
have  a  filler neck restrictor.   Thus,  the  onboard  control
system  for  these  HDGVs  would  require the additional hardware
associated with  the filler  neck  restrictor   already  present on
vehicles using unleaded  fuel if  they  were to  use fillpipe seals
similar to those used on LDVs and LDTs.

     Although  application of an onboard  control  requirement to
the heavier HDGVs  is not as straightforward  as  for the lighter
weight HDGVs  and  may be more  costly,  there  does not  appear to
be  any  technological reason  why onboard  control would  not be
feasible for  the heavier GVW HDGVs.   One  possible  approach for
applying an onboard  control  requirement to HDGVs  if  costs wer'e
excessive, would  be to  require  control for  the  lighter weight
HDGVs  (under  14,000  Ibs  GVW)  and defer control  for the heavier
weight HDGVs  (over 14,000 Ibs GVW).

     D.    Safety Considerations

     In  addition   to   concerns   about  the   performance  and
durability  of  onboard   control   systems  for  LDVs,   LDTS,  and
HDGVs,   there   are  some  potential  safety considerations  which
require evaluation.   If  a  blockage of  some  type occurs  in the
line  from the  fuel  tank  to  the  charcoal   canister, pressure
buildups within the  system  may  lead  to damage  of  the fillpipe
seal and  possibly  a spurt  of  gasoline  from  the  fuel   inlet.
Second, if the  automatic shut-off of  the  gasoline  nozzle fails
to operate properly,  an  overfill of the  tank could occur which
also could result  in damage  to  the fillpipe  seal and  a spurt of
fuel.  Third,  there  is  also the  possibility  that  a  failure of
the vapor/liquid separator and rollover check valve in the line
from the fuel  tank to the  canister and an  improperly operating
automatic  gasoline  nozzle  shut-off  could  lead   to  a  tank
overfill  and  fuel  flowing  up  the  line  and  poisoning  the
canister.

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     These  problems  could  likely be  resolved with  a pressure
relief valve which would vent  vapor  or gasoline overpressure to
the  environment  should  problems  occur.   However,  prototype
pressure  relief  systems   have not  been  fully  developed  and
failure  modes  have   not   yet  been  adequately  identified  and
evaluated.   Also,  increasing  the diameter  of  the  vapor  line
from the  fuel  tank  to the charcoal canister  and  increasing the
vapor  flow  capacity  of   the  vapor/liquid   separator  and  the
rollover  check  valve  should  decrease  overpressure  problems.
Thus while  some  questions  relative to the safety  of an onboard
system remain  unanswered,  any problems should  be  solvable with
direct engineering effort.

     E.    Summary

     The work  conducted through  API  and later  by  ARCO suggests
that onboard  control is technologically feasible  for LDVs, and
evidence  is  that in-use durability  of these  systems should be
excellent.   Due  to  the fundamental  similarities  between  LDVs
and LDTs, onboard control  should  also  be  feasible  for LDTs.  In
fact, the onboard systems  would  likely be  nearly identical with
the possible exception of charcoal canister size.

     The demonstrated  onboard  technology  also appears adaptable"
to HDGVs.   For those HDGVs of less  than  14,000 Ibs GVW (65-70
percent  of  all  HDGVs),  the  application  of  onboard technology
would in  all  likelihood essentially be accomplished through an
extension of  LOT systems.  The  only major difference  might be
larger canister sizes  to accommodate  the  larger fuel tanks used
on some  of  these  HDGVs.   Onboard systems for  the  heavier HDGVs
(those whose  GVW exceeds  14,000  Ibs) would  be  somewhat  more
complicated and costly, but nevertheless appear practicable.

     It should be possible  to  minimize any  effect  of an onboard
vapor recovery  requirement on exhaust  and  evaporative emission
levels through the proper design of the onboard system.

     There are  some  potential safety  considerations which must
be identified,  evaluated,  and resolved.  However,  it is likely
that  these  can  be  adequately addressed  through  the use  of  a
pressure relief valve within the fuel delivery system.

     Although  control systems  could  be  applied  to  HDGVs,  we
have not quantified  the costs, benefits,  and  cost effectiveness
for these vehicles  at this time.  HDGVs  comprise  only  about  3
percent of  the gasoline-fueled vehicles produced  each year and
represent on the  order of 5 percent of annual nationwide total
gasoline   consumption.[6]     The  remainder    of    this   paper
concentrates on the  costs,  benefits,  and  cost effectiveness for
LDVs and LDTs.

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III. In-Use Performance of Onboard Systems

     A.    Introduction

     Losses in  the effectiveness of  in-use  onboard systems can
occur  through  two  mechanisms:    tampering  or  deterioration of
the   efficiency   of   the   system.     Tampering   occurs    when
individuals  purposely  disable  part  or  all  of  the  onboard
control  system.   Tampering could occur  with the  fillpipe  seal
and   the  charcoal   canister   and    related   hoses.     System
deterioration  occurs  when  control  efficiency  of the  onboard
system  declines  with  mileage  and/or  time.    Either  mechanism
renders   the   onboard  vapor   recovery  system   partially  or
completely   ineffective.    The   projected   effects   of   these
mechanisms on onboard system performance are discussed below.

     B.    Tampering

     1.    Fillpipe Seal Tampering

     It  is  possible  that  fillpipe  seals could  be  subject to
tampering  similar  to  that   reported   for  the  tampering  with
fillpipe  restrictors  in  vehicles  using  unleaded fuel,   since
violation of the  leaded  fuel restrictor would  also destroy the
vapor recovery seal.  Fillpipe  tampering  data is available  from
the  National  Enforcement   Investigations   Center   (NEIC).[7]
These data show  substantial  differences  in  fillpipe  restrictor
tampering  in  areas  which  have  inspection/maintenance   (I/M)
programs  versus  non-I/M areas and different  levels of  fillpipe
tampering for LDVs  and  LDTs.   (See Figure B-l  of  Appendix  B.)
A  linear regression  of  this  fillpipe  tampering data  versus
mileage for  1982 produces the following results:

      LDVs;          I/M Areas:         TAMP = -1.43 + 1.14(M)
                    Non-I/M Areas:     TAMP = -0.78 + 1.65(M)

      LDTs;    -      I/M Areas:         TAMP = 3.55 + 1.14(M)
                    Non-I/M Areas:     TAMP = 10.6 + 1.65(M)

Where:

      TAMP =  Tampering  incidence  expressed  in  percent   at  a
             particular  vehicle mileage.

         M =  Mileage/10,000 miles.

     It should be  noted  that the tampering  increase  rates  (the
change  in tampering incidence with  mileage)  for  LDVs  and  LDTs
are the  same.   This was taken  to be the case  because  the  size
of the LOT sample was too  small  (323 LDTs versus 1,999 LDVs) to'

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allow meaningful rates to be determined.   However,  the LDT data
were  used  to  derive  a  mean  tampering  level for  LDTs  at  the
average LDT mileage,  with  the  LDV tampering  rate being applied
to that single point.

     However, these tampering rates  are  conservatively high for
the  late   1980's  and  beyond  when  an  onboard   vapor  recovery
requirement  might  be  implemented.    The  primary  motive  for
fillpipe  tampering  is   to  permit   the  use  of  somewhat  less
expensive leaded fuel in LDVs and  LDTs designed  to use unleaded
fuel.  The tampering  rate itself depends on  the  availability of
leaded  fuel,  the  leaded  to unleaded  fuel  price differential,
and  the  actual difficulty  and  other effects of  the  tampering
process itself.   The  tampering rates given  above are  based on
data  gathered  in  the  Summer  of  1982,   when leaded   fuel  was
readily available  at a  differential of  about  five  cents  per
gallon and  fillpipe  tampering  was a relatively  simple process,
usually with  no  effect on  the  integrity of  the  filler  neck
itself.

     However,  in  the  late 1980's  and  beyond, leaded  fuel will
be generally  less available due  to lower overall  demand,  and
with  less  demand  it  is possible  that  the  leaded  to unleaded
fuel  price differential  would  decrease.    In  addition,  there
were only  a handful of  I/M programs in place  in  1982  when this
data was  gathered.   As more I/M  programs are  implemented over
the  next  few  years   tampering  should decrease.   Perhaps  most
importantly,   the  onboard   control   requirement   could   be
implemented with  a certification  performance standard  such  as
the   parameter   adjustment  requirement   for  carburetors   on
gasoline-fueled  vehicles.   This   requirement would   force  the
design of  filler  neck restrictors  and fillpipe seals  which are
a  more  integral  part  of  the  fillpipe,  thus  reducing  the
accessibility  and  success  of  tampering.   Therefore,  it  is
reasonable  to  project  that  fillpipe  tampering  will  decrease
markedly by  the  later  1980's.   After  briefly considering  the
rate  of   tampering   with   charcoal  canisters   and  hoses,   a
composite  tampering rate will  be  determined for LDVs  and LDTs
if  fillpipe   tampering  is  reduced  by  50  percent  due  to  the
reasons discussed above.

     2.    Charcoal Canister and Hose Tampering

     Tampering   with    the   charcoal   canister   and   related
connecting  hoses  would  also  destroy  the  effectiveness  of  an
onboard  vapor  recovery system.   Since   the  control  approach
expected  by  EPA  assumes  an   integrated  onboard/evaporative
emissions control system, currently  available data on tampering
with  evaporative  emission  systems  (canisters/hoses)   would  be
directly applicable  to  onboard controls   as  well.   Evaporative*

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                              -9-
emission control system tampering  rates  are also available from
the  National  Enforcement   Investigations   Center  (NEIC)  for
1982. [7]  The  tampering rates  are different  for  LDVs  and LDTs,
but  not  different  in  I/M  versus  non-l/M  areas,  since  the
evaporative  emissions  control  system is  normally  not  checked
during  I/M.   (See  Figure  B-2   of   Appendix   B.)    A   linear
regression   of  this  most   recent   (1982)  NEIC  evaporative
emissions control  system  tampering data provides the  following
results:

                      TAMP = -0.55 + .360(M)

                      TAMP =  2.85 + .360(M)

TAMP  and  M  are   as   described  previously  above,   and  the
explanation  regarding  the  derivation  tampering  incidence  and
tampering rates for LDVs and LDTs is also applicable.

     3.     Composite Tampering Rates

     It would  be  convenient  to  have  composite  tampering rate
equations for  LDVs and LDTs  for • computing the  in-use emission
reductions  expected  from an  onboard  vapor  recovery  system".
Since   tampering   with   either   the   fillpipe   seal   or  the
canister/hoses would disable  the  vehicle's onboard  system,  the
slopes  and   intercepts  of  the  different  tampering  equations
given   above  could  simply   be   added   for  LDVs   and   LDTs
respectively.  However,  this would  overstate the  total   effect
of tampering,  because some  vehicle owners  tamper  with both  the
fillpipe and  the  charcoal canister and  hoses.   Since  disabling
either  would eliminate the  effectiveness  of onboard  control,
just adding the equations  would lead to some double counting.

     To  determine  the  degree  of  overlap   in   tampering,  the
National Enforcement Investigations Center  data  discussed above
was analyzed.  After the overlap  tampering  was  accounted  for,  a
linear  regression  of the  combined  data  sets was conducted  and
the following regression equations were obtained:

       LDVs;              I/M Areas:      TAMP = -1.47 + 1.442(M)
                         Non-I/M Areas:  TAMP = -1.52 + 2.114(M)

       LDTs;              I/M Areas:      TAMP =   6.42 + 1.442(M)
                         Non-I/M Areas:  TAMP = 13.67 + 2.114(M)

     The  tampering  levels  in  I/M  and  non-I/M  areas  can  be
weighted  (40  percent I/M and  60  percent non-I/M)  according to
the fractions  of  the U.S.  population residing in  the  two types
of areas.   The results  of  this  tampering  rate  weighting  are
shown below.

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                              -10-


     LDVS; TAMP = -1.5 + 1.8452(M)

     LOTS; TAMP = 10.77 + 1.8452(M)

     The  weighted  composite  tampering  rate  equations  given
above  are  based  on  current  tampering  rate  data.   As  was
discussed above,  it is likely  that tampering will  decrease in
the future,  thus  improving the overall  in-use  effectiveness of
an onboard  vapor  recovery program.  To  estimate  this potential
decrease  in  tampering,   the  portion  of  the  above  composite
tampering rates associated with the  fillpipe  will  be reduced by
50 percent.   The portion  of  the  composite  tampering  rate  due
solely  to  tampering  with  the  fillpipe  was  taken  to be  the
difference  between  the composite  rate  and  the  tampering rate
associated with  the evaporative HC control  system.   The  result
of decreasing this difference by 50 percent is shown below.

     LDVs: TAMP = -1.0 + 1.1026 (M)

     LDTs: TAMP = 6.81 + 1.1026 (M)

     These   projected   weighted   composite   tampering   rate
equations  will  be   used   in  calculating  the  in-use  emissio~h
reductions for onboard vapor  recovery  control.   These equations
will be  taken  as applicable  to 1988  and later model  year LDVs
and LDTs.

     C.    Deterioration

     As was  discussed  above  in Section  II.B.2.,  the  ARCO seal
durability  data   show  no  deterioration  of  the   onboard  vapor
recovery system effectiveness with  mileage.   This  is consistent
with historical  EPA certification  information which  shows that
the efficiency  of  evaporative  emission  control  systems   (which
are similar to vapor recovery systems),  do  not  deteriorate with
mileage.  Limited  in-use  testing  of  LDV  and  LOT  evaporative
emission  systems  shows  that  these  systems  do  function  as
designed.  At  the same time,  some small loss  of  effectiveness
with mileage,  on  the  order  of  a  few   percent,  would   appear
reasonable  due  to  contamination  of  the charcoal,  channeling,
aging,   leaks,  etc.   With  no  data,  it  is  not  possible  to
estimate  this  loss  quantitatively.   However,  the  tampering
rates of  the previous  section appear  large  enough to overwhelm
any expected  loss  in  efficiency  due  to deterioration.   Thus,
the losses  in system  effectiveness  due to  tampering will  be
taken to include any losses due to  deterioration.

IV.  In-Use Emission Control Effectiveness

     An  estimate   of   the  annual  or   lifetime   HC  emission
reduction  potential of  vapor-controlled  LDVs  and  LDTs  is  a

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                              -11-
function  of  annual  or  lifetime  mileage,  the  vehicle's   fuel
economy,  the   uncontrolled  refueling   emission  factor,   the
control  system effectiveness,  and  an  adjustment  factor   that
accounts   for   a   loss    of   effectiveness   in-use,   (i.e.,
tampering).   This  relationship  on an  annual  basis is expressed
below:

           HC = (VMT)(EF)(NSEFF)(NTAMP)
                           MPG

Where:

     HC =  Average  annual   HC  emission  reduction  per  vehicle,
           grams.

    VMT =  Average annual mileage, miles.

    MPG =  Average in-use fuel economy, miles per  gallon.

     EP =  The  uncontrolled refueling loss  emission factor, or
           4.54 g of HC per gallon of  dispensed gasoline.

  NSEFP =  Onboard control  system  efficiency of  new vehicles-,
           or 0.98.

  NTAMP =  An  adjustment   factor  which  discounts   for  in-use
           tampering.  NTAMP equals  (1-TAMP) for  any  given year.

     Estimates  of  in-use  (over the  road)  fuel economy  for new
LDVs   and  LDTs   are   based   on   projections   of  fleetwide
improvements for 1988 and later years.  Annual  vehicle miles of
travel  estimates  are  those used  in  the EPA  emission  factors
program.[8]    This   information  is   contained   in  detail  in
Appendix B.   The  new vehicle control  system  efficiency  of  0.98
and the range  of  tampering  rates as  a function of mileage  were
discussed above.

     The  uncontrolled  refueling  loss  emission   factor  (4.54  g
HC/gal) is based on  recent  work conducted by the  California Air
Resources Board (CARB).[9]   This figure  is 11  percent larger
than the  emission  factor  contained  in  the  EPA  emissions factor
document  (AP-42). [10]   The  CARB  emission  factor  was  selected
over the  AP-42 emission factor  for  three  reasons.   First, the
EPA emission  factor  document  expressed  uncertainty  about   it's
emission  factor value.  Second,  the  CARB  factor is based .on
data  at  least  5  years more  recent  than  the  AP-42  emission
factor.  And  third,  an increase  in  the  emission  factor  can be
explained  by   the   steady   increase   in  gasoline  volatility
(expressed as Reid Vapor Pressure)  over  the past  10  years.[11]
In  fact,   information   recently  submitted   to  EPA   by  General

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                              -12-
Motors indicates  that  4.54  g/gal may  be  conservatively low  for
today's commercial gasolines.[12]

     This  equation  and  these factors may  be used  to estimate
the  lifetime  emission reductions  for LDVs  and  LDTs.   For  any
given  model  year,   the  only  variable   would   be  the   fuel
consumption.   The  remaining  factors  for   each  year  of   the
vehicle  life  can be  determined and  summed  to  get  a   single
factor representative  for  the entire  vehicle average  lifetime.
Using an average  lifetime of  100,000  miles  for LDVs and 120,000
miles for  LDTs,  and assuming  that  the tampering  occurs  at  the
midpoint  in  each  year,  the  lifetime  HC   reduction  can  be
calculated for any model year.


                                      AL
     HC ftonsi -   (NSEFF) (EF)	  <^    (VMT  . NTAMP )
     HC (tons) -  (453.6)  (2foOO) (MPG)  ^      x        x


Working  through  the  mathematics   of  this  calculation,   the
following  equations  have  been determined  for  calculating  the
lifetime  tons of HC  emission  reductions  for  LDVs  and  LDTs..
These are  based   on  an average  lifetime  (AL) of  100,000  miles
for LDVs and 120,000 miles for LDTs.

     LDVS:  HC =  «4683
                  MPG
     LDTS:  HC = -5095
                  MPG
With these  equations,  the  average  lifetime  in-use  HC emission
reductions  from  onboard vapor  recovery  for  any  model year LDV
or  LOT  can  be  determined   using   the  in-use  fuel  economy
estimates .in  Table  B-3  of  Appendix  B.   For  example,  for  1988
model  year  vehicles,  LDV  and  LOT  reductions  of   0.0178  and
0.0264 tons respectively per  vehicle, would  occur.   These  will
be  used  in  a  later  portion  of the  analysis  to  calculate the
cost effectiveness.

     In addition  to  computing  the  annual  or lifetime emission
reductions  on  a  per  vehicle  basis,  the   nationwide   annual
reduction  in  the  overall  HC  emission  inventory  can  also be
estimated.    Determining  the   reduction   in  the   annual  HC
inventory for any given year  is  a  relatively  straightforward
calculation   involving   the  annual   gasoline  consumption  of
vehicles  employing  onboard controls,  the  emission  factor,  andv
the  in-use  control  efficiency of  those vehicles.   The  annual

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                              -13-
gasoline  consumption  of  controlled vehicles  is a  function of
their  total  registrations,  fuel  economy,  and  the  annual miles
of  travel.   These  can  be  expressed  mathematically  as shown
below.
     IR = (EF) (NSEFF)    ^  | REGxzSRxzNTAMPxzVMTxz
         (453.6) (2,000)  z=!
                                           s\ £j

                           REGyz SRy2NTAMPy2VMTyz
                                  MPGyz


The variables  are the  same  as  identified  above,  and  as noted
below:

     x   = LDVs

     y   = LDTs

     z   = time (years)

     IR  = annual HC inventory reduction  (tons)

     REG = new registrations  of  gasoline-fueled  LDVs or LDTs in
           each year z=l,n

     SR  = new vehicle  survival  rate  of gasoline-fueled LDVs or
           LDTs in each year

The values for these variables are given  in Appendix B.

     Working  through  the  calculations  above,  the   following
annual inventory  reductions  are projected from  all in-use LDVs
and LDTs with effective vapor recovery systems.

                   Annual  Reductions  (tons)

      1988         1989         1990         1995         2000
     41,200       77,500       108,400      213,300      257,500

One can see that  as  a greater portion of  the  LDV and LOT fleet
employs  onboard  control,   the  annual  reduction   in  refueling
emissions becomes substantial.

V.   Costs of Onboard Vapor Recovery

     Two  new  sources  of  information  on  .the  costs  of  onboard
vapor  recovery   hardware   have  become   available  since  the

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                              -14-
preparation  of  the  last  estimates  shown  in  Appendix  A.   The
first is a June 1983 draft  report  entitled "Manufacturing Costs
and Retail  Price  Equivalent of  On-Board Vapor  Recovery System
For Gasoline-Filling Vapors,"  prepared by  LeRoy  Lindgren under
contract to  API.   The  second  is  a  January 1984  cost estimate
presented by  API  in their  final  report on the  cost comparison
for  Stage  II  versus onboard  control  of  refueling  emissions.
The  information  contained  in  Lindgren's  report  was  one input
used by  API   in their  most recent  cost estimates  for onboard.
No updated cost estimates from the  auto industry were available
for this analysis.

     In this  section of the report, the  Lindgren hardware cost
estimates will be reviewed and  discussed  first.   This  will be
followed  by  a   discussion  of   the   onboard   cost  estimates
developed by  API  and an update  of the estimate  of  the  cost of
an onboard  vapor  recovery  system  for  a current  technology LDV
or LOT.  This section will  close with  a discussion of the sales
impact of an onboard control requirement.

     A.    Lindgren Report

     The Lindgren  report  to API  provides  an  estimate  of both
the manufacturer  (or  vendor)  cost  and retail  price equivalent
(or customer  cost)  of  a  complete  onboard  control  system.  The
estimates  of  these   two   costs   are   $12.95    and   $29.85,
respectively.  Tables  1  through  6  of Appendix  C  (taken from
Lindgren's draft  report) contain the bases  for these costs.

     Lindgren  estimated    hardware   costs  for    the   system
demonstrated by API  in  1978.   This system  is shown in Appendix
A, Figure  A-l.    This  system  was  a  fillpipe  seal,  additional
charcoal canister,  and separate  plumbing  for  the  evaporative
emissions and onboard  recovery systems.  Lindgren  attempted to
update  these  designs for  changes  in   LDV  engine  and  emission
control  technology  which have  occurred  since  1978.   However,
this  was not done  properly  in  every  case,   and  costs  for
components   already   on   current   technology    vehicles   were
attributed to the cost of an  onboard  vapor  recovery  system.
For example,  costs  were  included  for  a leaded  fuel restrictor
and modifications related  to  the electronic  control unit, both
which would  be present on current vehicles.

     Although most  of  Lindgren's component manufacturing costs
appear  reasonable,  there  are  two  other  major  deficiencies  in
the analysis.   First,   arithmetic  errors were  made  in  several
places  in the analysis,  and  an  error  was  made  in calculating
the costs  after   corporate  and  dealer markups  were  added.   A
markup  factor of  2.3 was used  instead of  1.8  as  specified  by
Lindgren  in   his  report.   As  was  mentioned  above,  Lindgren

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                              -15-
estimated a  customer cost of  $29.85.   Correcting  these errors
and applying  Lindgren's 1.8 standard  markup factor  brings the
customer  cost  down  to  $24.06.   Second,  based  on  previous
analyses  of  Lindgren's  cost  methodology,  standard  absorbed
overhead and  profit  absorption rates  appear  to be used  at the
corporate  and dealer  levels,  rather   than  incremental  rates.
This   results   in   a   substantial   overestimation   of   the
contribution  of  overhead and  profit  to onboard  control costs.
As will be discussed below,  it is believed  that  an incremental
approach  to  corporate  and  dealer  overhead  and  profits  is
appropriate for emission controls, resulting  in a markup factor
of 1.27 rather than  1.8.  Using this  incremental markup factor
brings Lindgren's estimate to $17.72.

     Thus,  Lindgren's  cost  estimates  cannot  be  used  directly
here,  but will have  to  be modified  to  include only the costs of
components  incremental  to  those  already  on  current  technology
LDVs and to  more  accurately  reflect appropriate  corporate and
dealer markups.  This process  is described  in the next section,
after  a review of the cost estimates released by API.

     B.    API Cost Estimates

     In  their  recent  final  report  comparing  Stage  II  and
onboard costs, API presented  their  updated cost  estimates for
onboard     controls.[13]       API      did      not     present
component-by-component  cost  estimates,  but  only  a  fleetwide
average  cost  of  $13.43.    This  estimate  included  different
canister sizes for LDVs  and LDTs  and  the  need for two canisters
on  some   vehicles.    The   fleetwide   average   estimate   was
calculated  using a cost  of $12.07 for  LDVs  or lighter LDTs with
one  canister,  $14.47   for  LDVs  or   lighter   LDTs   with  two
canisters,  and $20.87  for  all  heavier LDTs.   These  costs were
then  weighted   70  percent,   20   percent,  and   10   percent,
respectively, representing the projected  portions  of  the total
vehicle population.   When  system development  and certification
costs  are added,  this cost rises to  $15.26 per  vehicle  ( 1983
dollars).

     The API  cost estimates  did not  include  a  retail  markup
because they were  not  certain about  what  markup  figure  was
appropriate  or  how  the vehicle  manufacturer  or  dealer  might
choose  to  absorb or  pass  on  costs.   If  the  markup  factor  of
1.27 is applied,  a  fleet average cost of $19.38  per  vehicle is
obtained.   In the section  which  follows  directly,  it  will  be
seen  that  the marked  up  API  figure  is  in  the  range  of  the
updated estimate  of this report.

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                              -16-
     C.    Updated Estimate

     1.    Hardware Costs

     The  cost  estimates  here  are   based   on  an  integrated
evaporative emissions  and  onboard  control system  as  opposed to
the  separate  systems  on  which  the  Lindgren  and  API  cost
estimates  are  based.   This  design  is  expected  to  be  the
approach  preferred  by  the   manufacturers   because   it  makes
optimal use of  limited underhood space,  simplifies the design,
and reduces cost.   The key feature  of this  design is  that one
large  charcoal  canister  can be  used  for  evaporative  emissions
and onboard control rather than two separate canisters.

     The first step in developing the  updated  cost estimate was
to  decide  on what  components would  make up  the  system.   The
components selected were  mostly  the same  as those used  in the
API  demonstration program  and  priced  by  Lindgren.   However,
there  are  several   important  differences.   First,   as  was
mentioned  above,  an  integrated  onboard/  evaporative  emissions
control   system   was   assumed,   thus ~ eliminating   obvious
redundancies  between  the two  systems.  Second,  the  cost  of  a
pressure relief valve  was  included  which  might be necessary as
discussed  previously  in  Section   II.   D.    And,  third,  the
components which  are  present  on current vehicles  but  were not
present on  the  1978  vehicles  used  by Lindgren  were  excluded.
Once the  components  of the  system  were determined,  vendor and
retail price  equivalent  cost  estimates  were  developed  using,
and in  some  cases modifying,  the  manufacturing  cost  estimates
provided by Lindgren.

     The expected components  and their costs  are  summarized in
Table 1.  The vendor  costs  include material,  direct  labor, and
direct overhead and have  been  multiplied by a  factor  of  1.4 to
account for indirect  overhead  and  profit  at  the  vendor levels.
The 1.4 factor  for  vendor  allocation and  profit  was  taken from
Lindgren's  methodology  and   represents   a   standard  absorbed
overhead rate and rate of return for  this  industry.  These full
rates  are  appropriate  here  because  the  production  of  the
emission control equipment is  the primary  business activity for
the vendor and is not incremental in nature.

     These  vendor  costs  were  then  multiplied   by   1.27  to
estimate the  corresponding  retail  price  equivalent,  accounting
for corporate and dealer overhead and  profit.   Lindgren applied
a  factor  of  2.3 to  account  for   these  factors,  though  this
appears to be an  error,  since his  own methodology specifies  a
factor of  1.8.    The  1.8 factor  appears, again,   to  include  a
standard  absorbed  overhead  rate   for  both  manufacturer  and
dealer and standard profit margins for both.   These figures are.

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                               -17-

                            Table 1

              Onboard Vapor  Control  Hardware  Costs
              	(1983  dollars)	
Component or Assembly

Charcoal Canister LDV/(LDT)

Purge Control Valve

Liquid Vapor Separator

Fillpipe Seal

Pressure Relief Valve

Hoses/Tubing

Miscellaneous Hardware

Vehicle Assembly

Systems Engineering/Certification
                                          Incremental Costs
           Vendor

       $3.99/(7.83)

            0.74

            0.71

            1.12

            0.44

            1.90

            0.40
LDV Totals:

LOT Totals:
Vendor

Vendor
            Retail Price

            $5.07/(9.94)

                 0.94

                 0.91

                 1.42

                 0.56

                 2.41

                 0.51

                 1.00

 —              0.50


 $9.30  Retail $13.32

$13.42  Retail $18.19

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                              -18-
not appropriate  here because adding  emission control equipment
is  only  incremental  to  the  primary  business  of  assembling
automobiles,  and overhead and applied  assets are  not entirely
variable  with  respect  to  vendor  cost,   but have   significant
fixed  components.   This  is  particularly  true for  the  dealer,
who  would  experience   almost   no   effect  due   to  the  added
equipment.  The  1.27  factor  is  the result  of  an   incremental
analysis of corporate  and dealer overhead  and  profit which was
performed  as  part  of  a  recent EPA  mobile  source  regulatory
analysis for LDVs and LDTs.[14]

     The  size  of  the  carbon   canister   in   Table   1  is  that
associated with  a  fuel tank  which would give an  in-use driving
range  of  about   300  miles.   Using  the   in-use  fuel  economy
projections of  Appendix B  (Table  B-3)  for  1985-90,  LDVs would
require an average  fuel tank  size of 10-13  gallons,  LDTs would
require  an average  fuel  tank  size  of 14-18  gallons.    To  be
conservative,   in each  case,  the  higher   end  of  the  ranges  in
fuel tank sizes was used to size the canisters.

     As shown  in Table 1, an onboard vapor  recovery system is
expected to carry a  consumer cost  of $13.32 for  LDVs and $18.19
for LDTs.   Those LDTs  using  dual-fuel tanks (approximately  20
percent) may require two  separate  onboard  control systems for a
total cost of $36.38.   This  is  a  conservative assumption since
costs  could   likely  be  reduced  by  using one   large  charcoal
canister rather than two separate canisters.

     A  fleetwide  estimate  for   all   LDVs   and   LDTs  can  be
determined by sales  weighting the  costs given above.   Using the
projected  sales   for  1988  from  Appendix   B   (Table  B-3),  and
assuming 20 percent  of  LDTs have dual-fuel tanks, the fleetwide
average cost  is  calculated to  be  $15.08  as  shown  below.   For
future  calculations  this cost  will   be   rounded  to  $15  per
vehicle.

(10.582M) ($13.32) +  (2.768M) ( (.8) ($18.19)   + (. 2) ($36.38))=$15.08
                           13.35M

     This estimate of  $15.08 is  comparable to API's estimate of
$19.38  after  application   of   the  1.27  markup   factor  and
Lindgren's estimate  of $17.72 after  corrections  and  using  the
1.27  incremental  markup  factor.    The   main  reason  for  the
difference between this estimaJbe_and  those developed  by API and
Lindgren    is    because   >^E_PA^'   assumed    an    integrated
onboard/evaporative emission control approach as  opposed to two
separate systems.

     2.    Differences  Between  Past  and   Current  •• EPA N Cost
           Projections                                     '' '    -

     EPA's February  1980  report  projected a  fleet  average cost
of  $19.70.   When  inflated  to 1983  dollars,  this  cost  becomes

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                              -19-
$26  per  vehicle.   There  are  three  reasons   for   the  overall
decrease  of  $11 between  this  cost estimate  and  the  previous
estimate.

     First,  the  1980  projection  used  a  1.8  retail  markup
factor.   As  discussed  above,  it  is  now  believed   that  a  1.27
markup  factor  is more  appropriate;  this change  alone  accounts
for approximately 70 percent of the cost difference.

     The  second  reason is related  to  changes  in system mixes.
The 1980  projection  assumed  higher costs  in some  cases  due to
the use  of two  canisters  rather than  one  larger  canister,  or
due   to   a    manufacturer    not   choosing    an    integrated
onboard/evaporative emissions  control  approach.  This  accounts
for another 23 percent of the difference.

     Third,   there   have  been  changes   in   the  components
anticipated to make up  an onboard control  system and the prices
for some components (notably the  fillpipe  seal).  This accounts
for the remaining 7 percent of the cost difference.

     3.    Fuel Economy Impacts

     As was stated in  the previous  EPA  report  (Appendix A), the
implementation of  an  onboard  vapor recovery  requirement would
not  be  expected  to   impact   LDV   or   LDT  fuel   consumption.
Hydrocarbons  retained  by the  onboard  canister  represent about
0.1 to  0.2  percent  of  vehicular  fuel  consumption.    The  use of
this fuel by the engine could  thus  be  expected to decrease fuel
consumption  by  this  amount.    However,  the  additional  fuel
needed to  transport  the added  weight  of the  onboard system is
also in this range.  Thus, no  net change in fuel consumption is
expected.

     4.    Overall Cost Estimate

     As  discussed  in  the  previous  two  sections,   the  updated
LDV/LDT  cost  estimate  is  about  $15  per  vehicle and  there  is
adequate explanation as to why this cost is well below that of
February  1980.   However,  there are  still  reasons  to  believe
that  the  total  cost   of  onboard  control  could   be  somewhat
greater than $15 per vehicle.

     One,  this  figure  includes  primarily  hardware  cost  and
excludes   any   costs   associated   with   possible    fuel   tank
modifications, modifications  to  the  vapor  line  and  rollover
check  valve   between  the  fuel  tank and   the  vapor  canister,
modifications  to  make  the fillpipe more  tamper-resistant,  and
general    packaging    costs     to    fit    the    integrated
onboard/evaporative emissions  control system into the vehicle.

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                              -20-
Also,  there  may be  some  cost related  to manufacturer-specific
electronic control unit  (ECU)  modifications.   For example, some
manufacturers may  desire  to use specific  canister purge cycles
which  may  require  reprogramming or modification  of their ECUs.
Finally, since  the actual  pressure  relief valve discussed above
has not been  identified,  there is some uncertainty  in the cost
for that component.

     Two,  except  for the  allowance of a  dual system  for LDTs
with two  fuel tanks, the  system considered  herein  is somewhat
ideal.    Completely   integrated   onboard/evaporative  emission
control systems are  assumed in every case, and  this simply may
not be  possible.   For reasons of  canister production economies
of  scale,  underhood  packaging  restrictions,  or   for  unique
vehicle models,  manufacturers may  choose a  non-integrated two
canister system similar  to those  considered by  API.   As  was
discussed  above,   a  non-integrated  system would   increase  the
costs over those shown in Table 1.

     Three, in  the final analysis,  the  actual canister size and
purging system will  depend  on  the  details of  the test procedure
implemented   to  measure   compliance  with   an   onboard  vapor
recovery   requirement.     Factors   such   as    the   degree   of
interaction between  the  evaporative emissions and onboard test
procedures and  whether  the charcoal  canister would  have to be
purged  during  the  exhaust  emissions  test will affect  the size
of  the charcoal  canister  and  the  complexity  of  the   purging
system.  These  in turn  would affect  the  overall cost  of the
onboard system.

     To account for  these  and  other  potential costs, a range of
$15-25  per vehicle will  be used  rather than  the  single  cost of
$15 per vehicle.  While the final  cost  is expected to be closer
to $15 rather  than $25,  the use of $25 as an  upper limit will
allow the  sensitivity of  any  subsequent decisions  to this cost
to be addressed.

     D.    Impact On  Sales of LDVs and LDTs

     An  average purchase   price  increase of  $15   to   $25  is
expected to have no  discernible  impact on the sales of  LDVs or
LDTs and,  therefore,  no  effect on  the  profitability   of  the
companies  comprising the  regulated industry.   The  "own price
elasticity of  demand"  for LDVs and  LDTs  (that   ignoring  any
crossover purchases  in  other  vehicle classes)  is  approximately
-1.0, which  means  that  for  each 1  percent  increase  in price,
sales drop 1  percent.  With the  price of  an  average new LDV or
LOT now  exceeding  $10,000, a  $15  to  $25 first  price increase
would be predicted to decrease  sales  by  no  more  than  0.15 to
0.25 percent.  However,   there  is  some   question  whether  the

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                              -21-
elasticity of demand  is even meaningful  in  measuring the sales
impact of  a  $15 to $25  increase.   Such an  increase  would tend
to be  lost  in  the annual price  increases  occurring  at the time
of model year introduction.

     Furthermore,  onboard  controls are  not expected  to affect
operating  and  maintenance costs,  nor significantly  affect  the
owner's  experience of   refueling.   Thus,  there  should be  no
non-economic    resistance    which    will    affect   sales   or
satisfaction.   In  the   long  term,  an  onboard  vapor  recovery
requirement  should  have no  perceptible  impact on the  sales or
profitability of either the manufacturers or dealers.

VI.  Cost Effectiveness

     The   cost   effectiveness   of   onboard   control   can   be
calculated  using  the  LDV  and  LDT  in-use emission  reduction
equations developed in  Section  IV  and the  range  in  the average
costs of control  calculated  in  Section V.   The in-use emission
reduction varies  with each  model  year' s.vehicles  depending on
the fuel economy, and the  average  cost varies  somewhat based on
relative sales  of LDVs  and  LDTs.   The 1988 model year  will be
used here, since  it is  possibly the  first model  year  in which
an onboard requirement could be implemented.

     Referring to Appendix B (Table B-3) , the  1988  LDV and LDT
fuel economies  are 26.30  and 19.28  mpg  respectively,  and  the
sales are  10.582  and  2.768 million,  respectively.  Using these
fuel economy figures, the  lifetime  reduction for  LDVs is 0.0178
tons and for LDTs  the lifetime  reduction  is 0.0264 tons.  Sales
weighting  these  figures,  the fleetwide  average  lifetime  tons
reduction  is 0.0196  tons.   Dividing  these  figures  into  the
range  of  fleet  average weighted  cost of  $15-25 per  vehicle,
yields an  average  lifetime cost-effectiveness  value  of $766 to
$1,277 per  ton.   As  shown  in Table  2,  this cost-effectiveness
value  falls  in  the  range  of values for  other   mobile  source
related HC. control strategies, though nearer the end.

     On an  annual  basis,  the  cost  effectiveness  is  somewhat
larger.  Using  a  10-year vehicle life  for  LDVs and  LDTs,  a 10
percent  discount  rate,  and  assuming   payment   in  mid-year,
annualization of  the  $15 to  25  lifetime  cost  yields  an annual
cost of $2.34 to 3.90.   Assuming annual mileage is constant for
the  ten   years,   the   0.0196   fleet-weighted   lifetime   tons
reduction converts  to  0.00196  tons annual  emission  reduction.
The annual  cost  effectiveness  is   then  about  $1,194-1,990  per
ton.   The  simplifying  assumption   of constant  annual  mileage
results in a slight overestimation  of this  figure, since annual
mileage is higher  early in  the  vehicle's  life.   Nevertheless,
this provides a valuable  additional way of looking  at  the cost'

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                               -22-

                            Table 2

            Cost Effectiveness of  Mobile Source HC
              Control Strategies  (1983 $/ton) [1]
Control Strategy
                                           Cost Effectiveness
HDGV Evaporative Control

HDGE Useful Life

LDT Useful Life

LOT Statutory Standard

HDDE Statutory Standard

HDDE Useful Life

Interim High-Altitude Standards

Onboard Vapor Recovery  (with evap. benefits)

LDV Statutory Standards

Motorcycle Standards

Onboard Vapor Recovery  (w/o evap. benefits)

I/M

Auto Coatings

Transit Improvements
                                                         $112

                                                     $100-200

                                                         $406

                                                         $207

                                                         $319

                                                         $323

                                                         $416

                                                     $435-725

                                                         $508

                                                         $616

                                                   $766-1,277

                                                         $943

                                                       $1,301

                                                      $15,767
[1]   Short  ton

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                              -23-
effectiveness  of  an  onboard requirement,  especially  when  the
cost effectiveness of  an  onboard requirement  is  compared to HC
strategies  where  the  cost  effectiveness  is  calculated  on  an
annual basis.

     This estimate  of the cost  effectiveness of  onboard vapor
recovery  only  considers  the emission  reductions  derived from
eliminating  refueling  losses.   However,  preliminary  data from
EPA's   emission   factors   program   indicates   that    in-use
evaporative  emissions   appear   to   significantly  exceed  the
evaporative HC  standard.   This  occurs primarily  because  in-use
fuels typically have  higher  volatility than  the  fuel specified
for  certification   testing   and,  therefore,   produce   larger
amounts  of   evaporative  HC  which  cannot be adsorbed   by  the
current charcoal canisters.  Preliminary  estimates of the level
of  these  excess evaporative emissions  can   be  made  using  the
data  currently  available  from  EPA's   evaporative  emission
factors testing program which is  now  in  progress.  This  program
involves    evaporative    emission    testing   using   Indolene
(certification)   and   commercial  fuel   in  carbureted  and
fuel-injected  vehicles.   Based  on  preliminary  data  from this
program,  it is estimated  that  LDVs  have  evaporative emissions
in  the  range of 0.23  to  0.44  g/mi  using commercial  fuel  arid
0.16 to 0.24 g/mi  using certification fuel,  yielding an  excess
in  the  range of 0.07  to  0.20  g/mi.   A  best estimate  at this
time based  on this preliminary data is  evaporative emissions of
0.33  g/mi   using   commercial    fuel  and   0.20   g/mi   using
certification fuel, for an excess of 0.13 g/mi.   Although data
is not available for LDTs, one would  expect  results in the same
ranges  since LDV  and LOT  evaporative control systems  are very
similar.  Simply multiplying the best estimate of these  excess
evaporative emissions by the average  lifetime for LDVs and LDTs
(100,000  and  120,000  miles,  respectively)   and   converting  to
tons yields lifetime  excess  emissions  of 0.0143  tons  for LDVs
and  0.0172   tons   for  LDTs.   The  fleet-weighted  LDV/LDT  per
vehicle excess  would  be 0.0149  tons  of  HC   lifetime  or   0.0015
tons annually.

     Since  refueling  only  occasionally  coincides  with  the
occurrence  of  evaporative   emissions,   the larger  charcoal
canister  associated  with   an   integrated  onboard/evaporative
emission  control  system  could  also  control   these   excess
evaporative emissions at little or no extra  cost.  Adding these
benefits  to  those  from  onboard  control   improves  the  cost
effectiveness  by   approximately  43  percent.   If  all   excess
evaporative   HC emissions  were  controlled,   the   lifetime cost
effectiveness of onboard control  would  become $435  to  $725  per
ton  and  the  annual  cost  effectiveness  would  become $678  to
$1130 per ton.

-------
                              -24-
     As  indicated  above,  the in-use  evaporative  emissions data
is  preliminary  as all  testing  has  not  been  completed.   As
additional data become available,  it  will be possible to make a
firmer   estimate   of   excess   in-use   evaporative  emissions.
However,   regardless   of   the   magnitude   of   excess   in-use
evaporative emissions, the onboard control  system does have the
potential   to   control   a   large   portion  of   these   excess
emissions.   This  additional  HC  control,  if credited  towards
onboard  control,  would improve  its  cost  effectiveness.   While
not  central to  the  issue  of  controlling  refueling emissions
through  onboard  vapor recovery, this  potential  for  control  of
excess   in-use  evaporative  emissions  provides  an  additional
perspective  on  the  value  of  implementing an  onboard  vapor
recovery requirement.

VII. Leadtime Requirements

     If  an onboard  vapor  recovery  requirement were implemented,
it  is estimated  that  approximately 24 months  of  leadtime would
be necessary before the systems could  be required on production
LDVs  and  LDTs  once   a   rule   is  promulgated.   This  leadtime
estimate  is based  on engineering  judgment,  and  on leadtimes
necessary  in similar,  previous  EPA  rulemakings.   These  include
the  original  1978  6.0  g/test  LDV/LDT  evaporative  emission
standard which was  implemented  in  just one  year,  the 1985 HDGV
evaporative  emission  standard  which will  be  implemented  with
two  years  of  leadtime,  and  the   1981  2.0  g/test  LDV/LDT
evaporative emission standard which  was  also implemented in two
years.   The  two-year  leadtime  estimate  to  implement  an  onboard
vapor recovery program is based on the following considerations.

     A  program  to comply  with  an   onboard requirement  would
first    include    approximately    six    months    for    the
vendors/manufacturers to  develop and optimize working prototype
systems  applicable to  all  of  their  different vehicle  models.
Next,  initial  verification of  the  fillpipe seal  and  pressure
relief  valve  durability  could  be conducted  in  two  months  or
less  under   laboratory  conditions.    However,   purge   system
optimization and  optimization  and proveout of the  integrated
onboard  vapor  recovery/evaporative  emissions  control  system
would  require  some vehicle  testing,  as would verification  of
the efficiency and durability of the  fillpipe seal and pressure
relief  valve.   This vehicle testing  would require four  to six
months,  based  on  manufacturer  estimates  for  similar  in-vehicle
testing  programs.   Thus, prototype   testing  and  proveout  is
estimated to take 12 to 14 months to complete.

     Although many of the components  of  an onboard system would
be   "off-the-shelf"  or   readily   fabricated   from  existing
production tooling, some  tooling changes  would  be necessary for'
some components,  such as  larger  charcoal  canisters.  However,

-------
                              -25-
the  critical  items   in  terms  of  production  tooling  are  the
fillpipe seal  and  pressure  relief valve.  If  the fillpipe seal
and  pressure  relief  valve  used  are  some   form of  currently
available  component,   then   only  the  question  of  capacity
exists.   Capacity  is  necessary  to  meet  long  term demand  in
excess  of  13  million  units  per  year.  If  the   vendors  and
manufacturers  ultimately  settle  on  prototype  designs  which
would  require  significant  tooling  changes   or  completely  new
production,  or if  current production capacity  is insufficient,
then longer tooling leadtimes may be required.

     In  any  event,  commitments  leading to   production  tooling
changes  could  probably  be  made  after  the   initial laboratory
verification of  the  fillpipe  seal  and  pressure  relief  valve
durability.  If  vendors/manufacturers   are  able  to use  seals
similar to those used in  the  1978 vehicle  demonstration program
and  an  acceptable pressure  relief  valve  is   available,  then
total  tooling  leadtimes  of   three   or  four   months  would  be
necessary.   If fillpipe seals  and  pressure   relief  valves must
be  procured  from  modified  tooling,  then  leadtimes of  six  to
eight months are reasonable.   If  new  tooling must be developed,
then leadtimes for tooling will require  approximately 12 months
or  perhaps  longer.  Thus,  the range  for  tooling  leadtimes  i-s
three months to  one year or  more, depending  on the  source  of
the  fillpipe seals  and  pressure  relief valve.   Assembly line
tooling  changes  would  be  handled   during  normal  model  year
changeover, and thus would have no effect on this estimate.

     Finally,  some time  would  be required to  allow  for  the
normal  EPA  certification  process.   It  normally  requires  a
manufacturer 10  to  12 months  to  certify  its  entire  product
line.[15]

     Given  these  estimates   of   the  leadtime  necessary  for
development, laboratory testing,  in-vehicle testing,  tooling,
and certification,  Figure 1 shows how these  different estimates
were  put together  to  arrive  at a  leadtime  estimate  of  two
years.   The  critical  path  on  this  figure  is  6  months  for
development, 2  months for laboratory  testing,  4 to 6 months for
in-vehicle  testing,   and  10  to  12  months   for  certification.
Presuming  that  tooling  commitments  can  be  made  after  the
laboratory testing is concluded,  tooling is  not a critical path
even  if  the fillpipe  seal  and  pressure relief  valve  required
new   tooling.    Tooling  would  only   become    a   concern   if
commitments  were   delayed   until   after    the   completion   of
in-vehicle testing  (12-14 months).

     In  summary,  a  leadtime  period   of   two  years  appears
reasonable to implement an onboard  requirement.  Of course,  the
model year  of  implementation  for an  onboard  requirement  would,
depend on when  a  final rule  was promulgated.

-------
                                                  Figure 1
                                                         »
                                     Onboard Vapor Recovety Leadtime
                                                                I
                                                                    Certification
                                                                                                              I
                                                                                                              to
                                         If               If               If
                                  Current Tooling  Modified Tooling     New Tooling
                                      3~4 mo-           6-8 ,mo.            12 mo.
                                  1	1	
                                        Tooling
                                  Lab
Prototype
I	
Development
                                Testing   In-Vehicle Testing
                              -t-
    FRM
Promulgation
                                                 12
                                               MONTHS
15
18
21
                                     24

-------
                              -27-


VIII.  Onboard Control Versus Time

     When  considering  the  implementation  of  onboard controls,
it is of  value  to determine how much  time  would be required to
gain control  of a majority of  the  annual  LDV  and  LOT gasoline
consumption.  This, of course,  depends  on  the vehicle scrappage
and  replacement  rates,  the annual  vehicle miles of  travel and
the vehicle fuel  economies.  Consequently,  the portion of total
LDV  and  LDT fuel  usage  (and  accompanying  refueling  emissions)
which would be  controlled  as  a function of  time beginning with
the model  year  of implementation is estimated  below.   For this
analysis  it  is  assumed that  implementation begins in  the 1988
model year.

     A.     Total Fuel Consumption

     To  determine  the  portion  of  total  LDV  and  LDT  fuel
consumption controlled as a function of time  the controlled and
total  LDV  and  LDT  fuel  consumption  must  be  estimated  by
calendar  year.    A total  gasoline  consumption  by  a  specific
model year's vehicles  in  a  given calendar can  be derived using
the expression given below:

     GC -  (REG)(SR)(VMT)(VMTGR)
               (MPG)(ODOM)

     where:

     GC = gasoline consumption  (gallons)

    REG = new vehicle registrations for that model year
           (function of model year)

     SR = survival rate of new vehicles in the calendar year of
          interest (function of age)

    VMT = average annual mileage of the vehicles  (function of
          age)

   VMTGR = growth rate in average annual mileage of the vehicle
           (function of model year)

    MPG = new vehicle in use fuel economy (function of model
          year)

   ODOM = Usage pattern factor to account for the different mix
          of urban/rural driving and average daily  mileage on
          average in-use fuel  economy (function of age)

     Data  for the input  parameters described  above sis provided-
and referenced in Appendix B.   However,  a  few explanatory notes

-------
                              -28-
are  appropriate.   First,  the approach  used here  models total
LDV  and  LOT fuel  consumption using  twenty model  years  of LDV
and  LOT  registrations  (e.g.,  1988   fuel  consumption  would be
modeled  using  registrations  from   1988   to  1969   inclusive) .
While  it  is recognized that  there are  a  small  number  of  LDVs
and  LDTs  older than  20  years still  in-use,  their contribution
to  total  fuel  consumption is  relatively   insignificant  due to
their  low  registrations  and average  annual VMT.   Second, Table
B-2  contains  average annual VMT  data for   LDVs and LDTs.   This
data is applicable  for  pre-1982 model year  LDVs  and LDTs.  For
1982 and later  LDVs  and  LDTs, average annual  VMT was projected
to increase at  a  rate of  0.8 percent per  year  for LDVs and 0.4
percent  per  year  for  LDTS. [16]   Last,   calculation  of   fuel
consumption included a usage pattern factor  (ODOM)  to account
for  the fact  that the mix of urban/rural  driving and the daily
vehicle miles  of  travel  both  change  as an LDV  ages,  and  this
affects  the  in-use  fuel  economy   in  any  given   year  of   a
vehicle's life.  This applies to LDVs only. [16]

     Given this data, total LDV  and LOT  fuel consumption in any
given calendar year  can be  calculated by simply determining the
fuel consumption  of  each  model  years  LDVs  and  LDTs in the  year
of interest and summing  the consumption from  each model yearrs
LDVs and LDTs to  derive a total.   This  method of calculation is
shown mathematically  in the expression given below:
                            V 7   (VMT GRv
                            v, z _ v , z _ v ,
                         (MPG^x)(ODOMVfZ)

                 (REGt,x)(SRt,z)(VMTt,z)(VMT GR
                              (MPG   )
                                  t, x
                                  — r --

     v = LDVs, t = LDTs, x = model year, y = years,
     z = vehicle age
In this method  of  calculation y = 1  would  be the calendar year
of interest,  and  all data used  would begin with  that year and
then  going back  20  years.   Total   fuel  consumption  would  be
determined  by summing  the  consumption  of  the  most  recent  20
model years LDVs and LDTs in the calendar year of  interest.

     B.    Controlled Fuel Consumption

     Calculation  of  the  controlled  fuel  consumption requires
only two additions  to the discussion  given  above.  First,  since
controlled consumption  is not assumed to begin  until 1988, the
period  over  which  controlled  consumption  will  be   calculated
varies from 1 model year  in  1988 to  13 model  years in 2000 (or
presumably  longer  were  more  data  available  with  which  to,
calculate  controlled  consumption after  2000).  Second,  as was

-------
                              -29-
discussed   previously,   tampering   with   the   fillpipe   or
evaporative   emission   system   will   eliminate  the   control
effectiveness  of the  onboard vapor  recovery  system  of  those
vehicles.  Thus, the  fuel consumption of  tampered LDVs and LDTs
must be  factored out.  This  can  be  accomplished using the NTAMP
factor  described previously.  NTAMP  is  a function  of mileage
and  is  different for LDVs and LDTs.   For any  given  mileage in
the  life  of  an LDV  or  LOT,  NTAMP  =  1-TAMP,  where TAMP  is the
percentage tampering calculated  using  the projected composite
tampering rate equations given in Section III.B.3.  The mileage
used in  the  tampering rate  equation  for  each  model  years LDVs
and  LDTs  includes  the growth rate  decribed above for  LDVs and
LDTS.

     Controlled  fuel  consumption in any  calendar year  is then
the  sum   of  the   fuel   consumption   of  each   model  year's
non-tampered  LDVs  and LDTs  in  the calendar  year of  interest.
This method  of calculation  is shown mathematically  below.  The
only difference between  this and  the previous  expression is the
limits  on the  summation  and the  inclusion  of  the  tampering
factor.
Controlled =        (REGV,X) (SRVyZ) (VMTVyZ) (VMTGRV/X) (NTAMPv/m)+
                               (MPGVfX) (ODOM^)
                   (REG t,x> (SRt,2> (VMTt,z> x)(NTAMPt,m>
                                     (MPG   )
                                         t, x
     C.    Discussion of Results
     The  portion of  the  total LDV  and  LOT  fuel  consumption
controlled  in  any  calendar year,  1988  or  later,  can  now  be
calculated.  Figure 2 compares  LDV  and  LOT gasoline consumption
which  would  be  controlled  by   an   onboard   vapor  recovery
requirement to total LDV and LOT  gasoline consumption, assuming
onboard  controls were  first  introduced  with  1988  model  year
LDVs and  LDTs.   Table  3 is  a  tabular  summary  of  the graphical
information  presented  in  Figure  2.    This  data  shows  that
control of 50 percent of all LDV  and LOT fuel consumption would
be  achieved  5 to  6 years  after  introducing  an  onboard vapor
recovery requirement and control of more  than  84 percent of all
LDV and  LOT gasoline consumption  would be achieved  by 2000 (13
years  after  control   is   implemented).    Without   tampering,
control  in  the  year 2000  would exceed  92 percent;  control  of
approximately  8.5  percent  of  consumption   is  lost  due  to
tampering.

     In terms of the separate  LDV  and  LOT fleets,  control of 50
percent  of  LDV  fuel consumption  would be  achieved  in  about  5
years and by  2000  89  percent of LDV gasoline  consumption would

-------
                               -30-

                            Table 3

         Gasoline Consumption of Non-Tampered Vehicles
                 With Onboard Emission Control
           Compared to Total Vehicle Fuel Consumption

           LDV Gas Consumption (billions of gallons)

        Total LDV         LDV Gas Consumption
Year  Gas Consumption     Controlled Vehicles    Percent Control
1988
1989
1990
1991
1992
1993
1994
1995
1995
1997
1998
1999
2000


Year
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
49.0
48.0
46.9
45.9
45.0
44.0
43.1
42.3
41.6
41.0
40.5
40.2
40.0
LOT Gas
Total LOT
Gas Consumpt
24.4
24.0
23.4
23.0
22.7
22.4
22.2
22.1
22.1
22.0
22.0
22.0
22.2
6.0
11.3
15.8
19.8
23.2
26.1
28.4
30.3
31.9
33.1
34.2
34.9
35.5
Consumption (billions of gallons)
LDT Gas Consumption
ion Controlled Vehicles Percent
2.4
4.5
6.3
8.0
9.5
10.9
12.1
13.2
14.2
15.0
15.8
16.5
17.0
12.2
23.5
33.7
43.1
51.6
59.3
65.9
71.6
76.7
80.7
84.4
86.8
88.8


Control
9.8
18.8
26.9
34.8
41.9
48.7
54.5
59.7
64.3
68.2
71.8
75.0
76.6

-------
                               -31-

                         Table  3-Cont'd

         Gasoline Consumption of Non-Tampered Vehicles
                 With Onboard Emission Control
           Compared to Total Vehicle Fuel Consumption

       LDV and LPT Gas Consumption  (billions of gallons)

                                 LDV &
      Total LDV & LDT     LDT Gas Consumption
Year  Gas Consumption     Controlled Vehicles  "  Percent Control

1988        73.4                   8.4                  11.4
1989        72.0                  15.8                  21.9
1990        70.4                  22.1                  31.4
1991        69.0                  27.8                  40.3
1992        67.7                  32.7                  48.3
1993        66.4                  36.9                  55.6
1994        65.3                  40.4                  61.9
1995        64.4                  43.5                  67.5
1996        63.6                  46.1                  72.5
1997        63.0                  48.2                  76.6
1998        62.5                  49.9                  79.8
1999        62.2                  51.4                  82.6
2000        62.2                  52.5                  84.4

-------
   80 *
   70 .
   60 .
   50 ,
CO
c
o
3  40
W
C
o
HJ
   30
   20
   10
        A
             -32-


          Figure 2


Controlled vs.  Total Gasoline

Consumption for LDVs and LDTs


         1988 - 2000
Total Consumption


Controlled Consumption


Controlled Consumption


Controlled Consumption
                      LDV & LDT


                      LDV


                      LDT


        	1	1	1	1	f.	»	1     i	1	1	1	«

     1988 1989 1990 1991 1992 1993 1994 1995 1996 1997  1998 1999 -2000

-------
                              -33-
be  controlled.   For LDTs,  50 percent  control would  require 6
years and 77 percent control would be achieved by 2000.

     This method  of determining the time  for  achieving control
of  refueling  emissions  differs   slightly   from  that  used  by
Lindgren,[17]  which  estimated  the  fraction  of  the  vehicle
population which  would  be equipped with  onboard  gasoline vapor
controls  over   time.    The  fraction  of   dispensed  gasoline
controlled  is  more  appropriate  than  the  fraction  of vehicles
controlled,  since refueling  loss  emissions are  a  function  of
the amount  of  gasoline  dispensed  and  not simply a  function  of
the number of vehicles in the fleet.

IX.  Conclusions

     The  data  from  the  API  demonstration  program  and  the
manufacturers'  previous  comments   both  indicate  that  onboard
control  of   refueling  emissions from  LDVs,  LDTs,   and  lighter
weight  HDGVs   should   be  technologically  feasible   using   a
fillpipe  seal   and  an  integrated   onboard/evaporative emission
control  system.   Onboard control  should  also be  feasible  for
the heavier  HDGVs,  but  the  systems used on  heavier  HDGVs would
be somewhat more  complex  and  costly.   The implementation issue's
for the  control  of  heavier HDGV  refueling  emissions  could  be
worked out  in  a  manner  similar  to  the  approach  used  in  the
recent HDGV evaporative  emissions final  rule,  so  control  of
virtually  all  of the  gasoline-fueled  motor   vehicles  may  be
possible.  Implementation of  an onboard requirement should have
a negligible impact on the vehicle's exhaust emission  levels.

     An  in-use  control  efficiency of  98  percent  is expected,
with  negligible  deterioration  for a   well-maintained vehicle.
Using  the   tampering  rates  expected   in   the   late   1980's  and
beyond, owner tampering with  the filler neck restrictor  and the
charcoal canister could  reduce the average  lifetime efficiency
to 91.8 percent  for  the sales-weighted fleet  of  LDVs and LDTs.
Using  1988   projected  fuel  economies   for  LDVs  and  LDTs,  the
fleet average  lifetime  reduction  in  refueling HC  emissions  is
.0196 tons per vehicle.

     An integrated  onboard/evaporative emission  control  system
is  expected  to carry a fleet  average  cost of  $15 to  $25  per
vehicle,    although    the   average   should    be   nearer   $15.
Implementation  of an  onboard  requirement  would  not  increase
lifetime  operating  or   maintenance   costs.    At  $15-$25  per
vehicle,   an  onboard  requirement   would  have  no  perceivable
impact on manufacturer or dealer sales.

     Using the  costs  and emission   reduction benefits mentioned
above,  the  sales-weighted   lifetime   cost   effectiveness  for-

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                              -34-
onboard  control  is  $766  to  $1,277  per  ton  of  HC  controlled.
The annual cost effectiveness is $1,194  to  $1,990 per  ton of HC
controlled.

     The  larger  charcoal  canister  of  an  integrated  onboard/
evaporative emissions  control system  could  potentially control
excess  in-use  evaporative emissions.   If the  preliminary  best
estimate  of  these  benefits  is  added   to  those  achieved  by
onboard control,  the lifetime cost-effectiveness  values fall to
$435  to $725  per  vehicle  and  the  annual cost effectiveness
becomes $678 to $1130 per vehicle.

     An  onboard   requirement  could   be   implemented  two  years
after  promulgation  of a  final  rule.   Control  of  refueling
emissions  from  50 percent  of the total annual  nationwide  LDV
and LOT  gasoline  consumption could  be achieved  in  five years.
Control of refueling vapors  from  more than 84  percent  of total
annual  nationwide  LDV  and  LOT  gasoline  consumption   could  be
achieved by 2000.

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                              -35-
                           References

     1.    "On-Board  Control  of  Vehicle  Refueling  Emissions
Demonstration  of   Feasibility,"   API  Publication   No.   4306,
October 1978.

     2.    "Recommendation   On    Feasibility    For    On-Board
Refueling Loss Control," U.S. EPA, OMSAPC, February 1980.

     3.    See reference 1, p.  25.

     4.    Letter,  F.  L. Voelz,  ARCO to E.  P.  Crockett,  API,
January 14,  1982,  and follow-up  telephone  conversation between
M. Reineman, U.S. EPA and F. L. Voelz, ARCO, August 18, 1983.

     5.    "Staff  Report,  Issue   Analysis  -  Final  Heavy-Duty
Engine HC  and  CO Standards,"  U.S.  EPA,  OANR, QMS,  ECTD,  SDSB,
March 1983.

     6.    "Transportation   Energy    Data    Handbook,"   Sixth
Edition, ORNL-5883, Oak Ridge National Laboratory, 1982.

     7.    "Motor Vehicle  Tampering  Survey  - 1982,"  U.S.  EPA~, "
National   Enforcement   Investigations  Center,   Larry   Walz,
EPA-330/1-83-001, April 1983.

     8.    "Draft  Mobile  3 Documentation,"  data  provided  by
Lois Platte, U.S. EPA, OMS, February 14,  1984.

     9.    "A  Report  to  the  Legislature  on  Gasoline  Vapor
Recovery  Systems  For  Vehicle  Refueling  at  Service  Stations,"
California Air Resources Board, March 1983.

     10.   "Compilation  of  Air   Pollutant   Emission  Factors,
AP-42, Supplement 9," U.S. EPA, OAQPS, July 1979.

     11.   "Trends  in Motor  Gasolines:   1942-1981",  E. Shelton,
et al, U.S. Department of Energy,  DOE/BETC/Rl-82/4, June 1982.

     12.   "Decision:    Vapor    Recovery   Control   Strategy,"
General Motors Corporation briefing to EPA,  February 3, 1984.

     13.   "Cost Comparison  For   Stage II  and On-Board Control
of   Refueling   Emissions",   American   Petroleum   Institute,
January 1984.

     14.   See for  example  the Regulatory Analysis  and Summary
and Analysis of Comments  prepared in  support of  the light-duty
diesel  particulate  regulations for  1982 and  later  model  year
light-duty  diesel  vehicles.   Both  are  available  in  Public'
Docket No. OMSAPC 78-3.

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                              -36-
                      References (cont'd)

     15.   Trap  Oxidizer  Feasibility  Study",  U.S.  EPA,  OANR,
OMSAPC, ECTD, SDSB, March 1982.

     16.   "The   Highway   Fuel   Consumption   Model  -   Ninth
Quarterly   Report,   prepared   by   Energy   and   Environmental
Analysis, Inc., for U.S. Department of Energy, February 1983.

     17.   "Manufacturing  Costs  and  Automotive  Retail  Price
Equivalent    Of    On-Board    Vapor    Recovery   System    For
Gasoline-Filling Vapors,"  Leroy H.  Lindgren,  Consultant,  Draft
Report, June, 1983.

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                  APPENDIX A
Onboard Technology Assessment

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                             December 1978
                     Recommendation on Feasibility
                                  for
                     Onboard Refueling Loss Control
                                 NOTICE

Technical Reports do not  necessarily represent final EFA decisions
or positions.   They  are intended to  present  technical  analysis of
issues using  data  which are  currently  available.   The  purpose in
the release of  such reports  is  to  facilitate  the exchange of tech-
nical  information  and  to  inform the public  of  technical develop-
ments which may form the  basis  for  a final EPA decision, position
or regulatory action.
              Standards Development and Support Branch
                Emission Control Technology Division
            Office of Mobile Source Air Pollution Control
                 Office of Air, Noise and Radiation
                U.S. Environmental Protection Agency

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I.   Introduction

     Refueling loss hydrocarbon  emissions,  estimated to be in the
range of 4-5  g/gallon,  can be controlled by use of  control equip-
ment at the service station (Stage II control)  or by  use of control
equipment  in  the vehicle  (onboard  control).   As  required  by the
1977 amendments to the Clean Air Act, the Emission Control Techno-
logy Division (ECTD)  of  EPA has  reviewed  and analyzed available
data on the feasibility and desirability of onboard  refueling loss
control which will be discussed  in this report.   This  information
will be  combined  by  the Office  of Policy  Analysis with available
Stage II control  information to provide the basis  upon which the
Administrator may choose the best of the two strategies.

II.  Summary of Conclusions and Recommendations

     Several hardware demonstrations and paper studies, Ref. 1, 2,
have been conducted to determine  the technical  feasibility and cost
effectiveness on  onboard refueling loss  control.  Much  of the
current information is  from  the  American Petroleum Institute (API)
onboard demonstration program, Ref.  3.   Other current  information
was obtained from motor  vehicle manufacturers in response to a June
27, 1978 Federal Register (43FR 27892) request  for  relevant informar
tion.   These demonstrations and  analyses  deal with the state-of-
the-art emission control technology.

     Analysis of  this  information  supports  the following conclu-
sions:

     1.   Onboard  refueling  loss  control  is  feasible  for light-
duty vehicles;

     2.   The most probable control system  uses hydrocarbon adsorp-
tion on  charcoal  (the same strategy  that  is  used for  evaporative
emission control);

     3.   Control effectiveness  can  be  as  high at 97% but depends
especially upon the vehicle  fillpipe/service station nozzle inter-
face and upon control technology design;

     4.   An  analysis of  data from  three  fillpipe/nozzle concepts
(fillpipe  seals,  nozzle  seals,  and  combination  fillpipe/nozzle
seals)  shows  that the  effectiveness  of  all three concepts is
approximately equal.  Durability effects have  not  been  extensively
evaluated,  especially for the nozzle seal concept;

     5.   A vapor/liquid  pressure  relief valve is required tb
protect the integrity of the vehicle fuel tank  during the refueling  •
process.  The pressure relief valve  can be  designed  to  function on
the fuel nozzle, or it may be  incorporated  as  part of the fillpipe

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                                  -2-
seal mechanism, which  would  be sealed-off by  the  fuel cap during
vehicle operation.  Durability effects have not been evaluated for
either  the  fillpipe or  nozzle pressure relief.   ECTD recommends
that the fillpipe/nozzle seal and  pressure  relief be located on the
vehicle if onboard controls are required.

     6.   Cost to  the  consumer for control of refueling losses on
light-duty vehicles will  probably range around  $17/vehicle.   The
$17 estimate does not  include costs for a  seal or pressure relief.
Cost  for  a seal  and  pressure relief,  if  used on  the  vehicle, is
estimated to  be about  $2.70.   The cost of a seal  on the nozzle
should be the  same  as  the cost for a Stage II nozzle.   Except for
the as  yet  undefined  durability of the  interface  seal no mainte-
nance costs are expected;

     7.   The  feasibility  of controlling  refueling  loss emission
from gasoline fueled trucks and diesel  fueled vehicles  has not been
evaluated to date.  Technical feasibility and cost effectiveness of
controlling these sources should be determined;

     8.   Minor increases in CO exhaust emissions seen for some of
the vehicles can probably be controlled by minor changes to either
the  refueling  loss control system  or to the  exhaust  emission
control system.  The ability to certify a  vehicle to a 3.4 g/mi CO
standard to 50,000 miles should not be  seriously  impaired;

     9.   The use  of  a bladder in the fuel tank  appears  to  be a
viable  alternative  control  strategy,  but  some  problems  exist and
technical feasibility is yet  to be demonstrated.

    10.   Considering the lead time needed  for regulation develop-
ment  and review  within EPA and  the  lead time  required by the
industry for  development  and application of technology,  implemen-
tation of onboard controls cannot  occur before  1983.

     ECTD recommends  that  the choice  between  onboard  control and
Stage  II  control of  refueling loss  emissions  be based  upon the
relative cost effectiveness   of  the  two  strategies  for  the   same
overall level of control and  air quality considerations.

     It is recommended that methods of  reducing the cost of onboard
refueling  control  systems  be  examined  by  considering  tradeoffs
between control system capacity and cost.    It  may be possible to
sacrifice  some  capacity  that is  only required  under  infrequent
conditions and  achieve  proportionately  more  significant  cost
savings.

     The feasibility  and desirability of  control of  refueling
losses  from  light and heavy-duty  gasoline  fueled  trucks and   from
diesel  fueled  vehicles should be  considered.   EPA should support
the development of  the bladder tank alternative for refueling  loss

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                                  -3-
control strategy.  If  regulations  are  to be developed for onboard
refueling  loss  control,  a certification  test procedure  must  be
developed.

III. Review of Available Information

     The data and information summarized in this section are based
on material  submitted  to EPA by  the American Petroleum Institute
and information received  in  response to a request for information
(43FR 27892) published  on June  27,  1978.  The API material, Ref. 3,
is the result of their most recent  study to assess onboard techni-
cal feasibility and compare the  cost effectiveness of  onboard
refueling controls  and  Stage  II  controls.   This study was initiated
at the urging of EPA.   Respondents to the Federal Register notice
include  General Motors, Ford,  and AMC.  The API, GM,  and Ford
information contain data  from tests  with onboard control hardware.
All respondents, with  the exception of AMC, submitted information
on  the cost  and the  desirability of onboard control  systems.

     1.   API Onboard Study

     The  API Onboard  Control  Study  was  structured to  address
questions regarding onboard feasibility which were posed to API in
a December 1977 meeting with  EPA.   The  API  study consisted  of thrse
tasks:  a vehicle concept demonstration, a fillpipe/nozzle concept
demonstration,  and  a  cost/benefit  analysis.    Exxon  Research and
Engineering  Company  and  Mobil  Research and  Development  Corpora-
tion were  the API contractors  for the vehicle concept demonstra-
tion.  Atlantic Richfield Company was  the API contractor for the
fillpipe/ nozzle concept  demonstration.  Exxon R & E completed the
cost/benefit analysis for API.

     The vehicle concept modification task  had  the  following design
objectives:

     1)   Minimum 90% overall refueling vapor  recovery.

     2)   No significant effect  on exhaust  emissions.

     3)   No significant effect  on evaporative  emissions.

     4)   Design should be durable, practical,  and  safe.

     The  fillpipe/nozzle demonstration  had the  following objec-
tives:

     1)   90% overall vapor control.

     2)   Compatible with existing vehicle  population.

     3)   Compatible with existing Stage II nozzles.

     4)   Design should be durable, practical,  and  safe.

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                                  -4--
     A review of the three API "contractor's activities is presented
below.

     Test procedure guidelines for the API work were discussed at  a
meeting with  API  on March 15,  1978.   Important  procedural  guide-
lines which  resulted  from that  meeting are summarized  as  follows:

     Fuel specification;   Indolene unleaded test  fuel was  used for
all exhaust, evaporative, and refueling loss measurements.

     Dispensed fuel quantity;  Test vehicles  were refueled to 100Z
of capacity from a condition of 10Z tank capacity.

     Fuel tank temperature/Dispensed fuel temperature;  The dispen-
sed  fuel  temperature  was  selected  to be  representative of  summer
refueling conditions in Los  Angeles during the  month of August,  or
about 85°F.   The  fuel temperature  in  the  tank was also  selected to
be 85*F.  Thus, the refueling was isothermal.*

     Purge Cycle;    For  the  purposes  of  the  API study,  the  only
driving cycle which was used for  purging the  refueling  loss  can-
ister is the LA-4 cycle.

     Individually,  these  test procedure  guidelines  are considered
to  represent real world situations in  a high  oxidant forming.
location, e.g., Los Angeles  during the  month of  August.   Collec-
tively, these guidelines  imply that  the  API  vehicles demonstrated
the  feasibility of  onboard control  systems in an approximate worst
case  condition.    This   reasoning  is  consistent  with  earlier  EPA
recommendations  that  API  err  on the conservative side  during
their study.   For example, Exxon used the following test  sequence
to quantify the exhaust emissions interaction between the refueling
control system and the exhaust emission control system:

     1)   Load ECS  (Evaporative  Control  System) canister to break-
through .

     2)   Condition the vehicle by driving 2 LA-4's.

     3)   Soak vehicle overnight.

     4)   Load  RCS  (Refueling Control  System) canister to  break-
through.
*This  represents  a conservative situation as survey  data,  Ref.  4,
 show  that nationwide  dispensed  fuel  temperatures  are  typically
 lower  than  tank  fuel  temperatures,  thereby representing  a  vapor
 shrinkage situation during the refueling process.

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                                 -5-
     5)   Condition the vehicle  by  driving 5 to  6  simulated  city
driving days (4.7 LA-4's with one hour hot soaks  in between and a
diurnal at  the  end  of  the  day)  to consume 90% of the  fuel  in the
tank.

     6)   Drain the fuel tank.

     7)   Block RCS canister  line.

     8)   Fill  tank to  40%, unblock RSC canister lines.

     9)   Conduct diurnal evaporative test  in SHED.

     10)  Drain tank to 10%.

     11)  Bring fuel tank liquid and vapor to  equilibrium  at  85°F
(shake the vehicle to accelerate  the equilibrium process).

     12)   Refuel  the  vehicle  to 100%  in SHED  with 859F fuel.

     13)  FTP

     14)  Hot soak evaporative test in SHED.

     Obviously, these  test procedures do  not  lend themselves  to a
routine laboratory certification  test procedure.  They do, however,
permit  an approximation of  how an  onboard control  system would
function in a severe "real-world" situation.

Exxon

     Exxon  assumed  the responsibilty  for modifying four  test
vehicles.  Their vehicles  included the following:

     1978 Chevrolet Caprice

     1978 Ford  Pinto

     1978 Plymouth Volare*

     1978 Chevrolet Chevette

     All  vehicles are designed to  comply with  1978 California
exhaust and evaporative  emission  standards  (.41  HC, 9.0  CO,
1.5 NOx, 6.0 Evap).
*  Vehicle  subsequently  dropped from test program  because  of high
baseline NOx levels.

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                              -6-






                            Table 1




      FTP Exhaust and Evaporative Emissions - Caprice

Baseline Configuration
Modified Configuration
Percent


n=4
Ave.
S.D.
n=4
Ave.
S.D.
Change

FTP Exhaust

Baseline Configuration
Modified Configuration

n=4
Ave.
S.D.
n=4
Ave.
S.D.
Exhaust (g/mi)
HC CO
0.345 6.48
0.033 0.56
0.338 7.10
0.010 0.59
-2 +10
Table
and Evaporative
Exhaust (g/mi)
HC CO
0.187 1.70
0.021 0.10
0.217 1.83 '
0.006 0.12
NOx
0.95
0.06
0.86
0.05
-10
2
Emissions
NOx
0.77
0.01
0.79
0.07
Diurnal
n=3
0.8
0.4
n=3
1.1
0.3


- Pinto
Diurnal
n=3
1.0
0.2
n=3
0.9
0.3
Evap. (g)
Hot Soak
2.1
0.4
2.1
0.2



Evap. (g)
Hot Soak
2.5
0.3
2.4
0.5
Total
2.9
0.8
3.1
0.4
+7


Total
3.5
0.4
3.3
0.7
Percent Change
+16
+8
+3
-6

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                                                -1-
                                              Table 3
                            FTP Exhaust and Evaporative Emissions - Chevette
Exhaust g/mi)

Baseline Configuration


Modified Configuration


Percent

n=3
Ave.
S.D.
n=3
Ave.
S.D.
Change
HC

0.27
0.02

0.26
0.05
-4
CO

3.7
0.32

3.6
0.28
-3
NOx

1.09
0.04

1.13
—
+4
Evap. (g)
Diurnal Hot Soak
n «* 4
0.8 2.6
0.36 0.79

0.3 1.2
0.08 0.15

Total

3.4
1.03

1.5
0.15
-56
*FTP + 3 Hot Start LA-4s

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             -8-




           Table 4




 Engine-Out Emissions - Caprice
FTP
HC
Baseline Configuration n=5
Ave. 1.28
S.D. 0.05
Modified Configuration n=5
Ave . 1 . 29
S.D. 0.09
Percent Change +1
*FTP + 3 Hot Start LA-4s
Engine-Out

Baseline Configuration
Modified Configuration
(g/mi) City Driving
CO NOx HC CO
26.42 1.17 41.86 733.86
0.72 0.04 2.00 39.27
32.04 1.17 42.32 853.52
2.4 0.04 1.90 61.51
+21 — +1 +16
Table 5 -
Emissions - Pinto
FTP (g/mi)
HC CO NOx
n=34
Ave. 1.83 52.7 1.25
S.D. 0.06 1.2 0.08
n=4 '
Ave. 1.77 60.1 1.12
S.D. 0.09 0.8 0.04
Day* (g)
NOx
38.68
1.17
41.34
3.17
+7

Percent Change
-3
+14
-10

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          Table 6




Refueling Loss Measurements



Caprice



Pinto




Chevette





Potential HC (g)

93.4
91.0
89.3
Ave. 91.2

51.0
59.3
53.1
Ave. 54.5

62.5
65.5
60.1
64.6
Ave . 63 . 2
SHED HC (g)

0.4
0.4
0.3
0.4

1.0
1.3
1.1
1.1

0.5
1.5
1.1
1.6
1.2
Percent Control Effectiveness




99




98





98

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                                                   -10-
                                                  Table 7




                                             Benzene Emissions
          Potential Benzene Emissions*SHED Measurements (ppm)        Measured Loss*SHED Measurements (ppm)
Caprice




Pinto
3.0




2.7
*A11 refueling at 85*F, RVP 9 lbs.t Benzene content 0.7%.
<0.05




<0.05

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                                 -11-
     The  Caprice is  a conventional  oxidation  catalyst  vehicle,
while  the Pinto  is  a three-way  catalyst vehicle with  feedback
carburetor control.   Vehicle descriptions and complete refueling
loss control  system descriptions  are  presented in Table  A-l  and
Figure A-l of  the Appendix.   The  refueling  loss canisters in the
Caprice, Pinto and Chevette are  described  as  follows:

               RCS
Vehicle   Carbon Volume   Carbon Mass    Carbon  Type*   Location

Caprice       5.01           1800  g       BLP-F3       Underhood

Pinto         3.04           1100  g       BLP-F3       Underhood

Chevette      3.04           1100  g       BLP-F3         Trunk

* Same carbon currently used  for controlling  evaporative emissions.

     The Exxon  exhaust  and evporative  emission test results which
compare baseline  and modified versions of the Caprice,  Pinto and
Chevette are summarized in Tables  1, 2  and 3.  Engine-out data are
summarized in Tables  4 and 5.  Refueling loss effectiveness test,
results are  summarized  in Table 6.  All  Exxon refueling emission
tests assumed a no-leak seal at the fillpipe/nozzle interface.  In
laboratory practice  this  was achieved  with  leak free connections
from the fuel nozzle to the fillpipe.

     Benzene emissions were measured during the refueling loss SHED
tests with both the Caprice and Pinto.   These  results are summari-
zed  in  Table  7.  The  Exxon  data  indicate that benzene control is
directly  proportional  to refueling  loss control effectiveness,
although current benzene  levels in the  SHED  are at the detectable
limit of the instrumentation.

     Table  8 presents  Exxon's manufacturer  cost estimates for
onboard control systems  for  the   1978  Caprice and Pinto.   These
estimates do not include the  costs for fillpipe sealing devices and
pressure reliefs, and  this hardware represents an additional cost
of approximately $1.50  (manufacturer's   cost)  per vehicle.  Exxon's
cost estimates  assume  an  estimated $.50 credit for downsizing the
ECS  canister,  which in the two  canister system, controls only
carburetor losses.   Exxon estimates the  incremental  cost of two-
canister refueling control systems to  range  from $8.25 to $10.53.
This estimate includes the above mentioned $.50 credit but does not
include the $1.50 cost  for the  fillpipe seal and pressure relief.
The  corresponding cost  range for  single canister refueling control
systems is $6.75 to $9.00.  For light-duty trucks, Exxon estimates
a cost range of from  $12 (large  single canister)  to  $20 (two
separate  refueling  loss  canisters or   multistage  purge systems).

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                                 -12-


                               Table 8

                  COST ESTIMATES FOR ONBOARD SYSTEMS(1)
Charcoal(2)

Canister and Valves

Tank Modifications

Hoses and Tubing

Assembling and Ins
      (§ $20.00/hr.


Credit for Downsized

s(3)
(4)
)
talling(6)

ed (7)
>1 Systein '
Caprice
$4.96
2.50
0.50
1.57

1.50
$11.03
$0.50
$10.53
Pinto
$3.03
2.00
0.50
1.72

1.50
$8.75
$0.50
$8.25
(1)  Estimates are made for cost to manufacturer  for  large volume
     production.

(2)  1800 g for the Caprice canister, 1100 g  for  the  Pinto
     canister at $1.25/lbm (Calgon BPL-F3 carbon).

(3)  Plastic container and valves.

(4)  Larger size float/roll-over valve.

(5)  3/4" vapor line from fuel tank to canister,  3/8" purge  line.
     EFDM tubing for vacuum control lines.

(6)  Additional 4.5 minutes labor at $20/hour.

(7)  Reduced size evaporative control canister.

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                                 -13-
     Exxon estimates the  average, cost for onboard control systems
to be  $9/vehicle.    This  is  based on  the  following assumptions:

     1)   Onboard systems are  designed  to control refueling emis-
sions from light duty vehicles with an average  fuel tank size of 17
gallons refueled  to 100%  capacity from  a  condition of  10% tank
capacity.   The onboard systems are designed to control hydrocarbon
emissions  at a level of 6  g/gal.

     2)   70% of  light-duty  vehicles  and single  tank light-duty
trucks  are  assumed to use single  canister  (evap + refueling)
systems.

     3)   30% of  light-duty  vehicles  and single  tank light-duty
trucks are assumed to use  two canister systems.

     4)   Light  duty trucks  with  dual or large fuel tanks consti-
tute approximately  10%  of the light-duty vehicle light-duty truck
population.

     In summary,  Exxon finds  that  onboard  refueling controls for
light-duty vehicles are a  technically feasible, practical, and cost
effective  alternative to Stage II vapor recovery.  They are of the
opinion that the  same may  also  be said for  light-duty trucks.

Mobil

     Mobil R&D has  modified  a 1978 Pontiac  Sunbird for control of
refueling  losses.   This  vehicle  has a  three-way  catalyst  with a
feedback carburetor control system, and  is certified  for complaince
with  California exhaust  and evaporative emission standards.
This modified vehicle  uses  a  single canister  which contains 1550
grams of Calgon BLP-F3 carbon.  The  complete vehicle and  refueling
loss  control system descriptions  are presented  in  the  Appendix.
Table 9 presents  comparisons of exhaust and evaporative  emissions
from  the  Sunbird for  the  baseline and  modified configurations; a
summary of  the  refueling  emission data  is  presented in Table 10.

     Similar  to Exxon's  findings, Mobil  states that  their test
results have demonstrated that onboard controls are  a feasible and
desirable  method  of controlling  refueling  losses from light-duty
vehicles and light-duty trucks.

Atlantic Richfield Company

     One  of the  requirements for  the  operation  of an  effective
refueling loss control  system is  the existence  of a no-leak seal at
the  fillpipe nozzle interface.   Atlantic  Richfield  (ARCO) has
developed working  prototypes of  fillpipe seals and nozzles.   ARCO
has  investigated  three types  of  sealing systems.   They  included:
                                                                  t
     1)   Modification  of  the vehicle fillpipe  to  achieve a seal
when used with conventional lead-free nozzles.

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                                               -14-

                                             Table 9
                  FTP Exhaust and Evaporative Emission Comparisons — Sunbird
Exhaust (g/mi)

Baseline Configuration
Modified Configuration
Percent

n=9
Ave.
S.D.
n=6
Ave.
S.D.
Change
HC
0.39
0.03
0.40
0.03
+3
CO
6.41
0.91
6.35
0.74
-1
NOx
0.98
0.07
0.99
0.03
+1
Diurnal
n=2
0.87
030
n=4
0.72
0.23

Evap. (g)
Hot Soak
1.12
0.13
1.27
0.37

Total
2.00*
0.34
2.11
0.56
+6
Includes five tests at low mileage where individual diurnal and hot soak results are not available.
                                             Table 10

                            Refueling Loss Measurements — Sunbird
Fuel Dispensed (gal)
16.4
15.3
16.9
17.1
HC Collected in Canister (g)*
85
73
113
109
Refueling Emissions
SHED Measurements (g/gal)
0.18
0.02
0.44
0.36
Control
Efficiency (%)
97
99
94
95
     Canister purged from a nominal working capacity load of 210 g.
     Fuel of nominal 9 Ibs. RVP.
     8 gpm refueling rate, using modified Stage II nozzle.

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                                 -15-


     2)   Modifications to both  the  fillpipe and  lead-free nozzle.

     3)   Modification  of a  Stage II  vapor  recovery  nozzle.

     A description  of each  type of  seal and  a summary  of the
durability data  collected with  each system are  presented below:

     Fillpipe seals;    Two types  of  fillpipe seals  have been ex-
amined.   They are a rotary grease  seal  (similar to grease  seals
used  on  rotating machinery  shafts), and  a  doughnut shaped  seal.
The material types for these two seals  are a  compounded nitrile and
thermosetting urethane,  respectively.   More complete descriptions
of  these  seals,  including durability  data,  are  found  in Figure
A-5 and Tables A-2 and A-3 of  the  Appendix.  Appproximately thirty
days of durability tests  with both types of seals  have demonstrated
that  the rotary seal is more  effective, basically due  to the
absence of  expansion problems  when exposed to gasoline  liquid and
vapor  atmospheres.   The  seal effectiveness of the prototype  fill-
pipe and nozzle  hardware  are  determined by a bench  test  apparatus
which  pressurizes  a  particular  system  and measures the  resulting
leak  rates.    Seal  effectiveness  calculations  are  determined  by
dividing the leak rate by a nominal fueling rate  (assumed to be 7.5
galIons/min.).   Durability tests  conducted  with  the  rotary  seal
have demonstrated that the rotary  seal  is effective  after  700-1000
nozzle insertions,  which correspond to  the life of the vehicle^

     Combination fillpipe/nozzle seals;    These  systems  consist  of
connecting parts on both  the fillpipe and nozzle.   Figure A-6  is  an
example of a  prototype design  evaluated by ARCO.  Durability test
results with these systems are similar to results  obtained with the
rotary seal.

     Nozzle Modification;   Working  prototypes  of vapor  recovery
nozzles,  modified  for refueling loss control,  have  been developed
by OPW and Emco Wheaton and evaluated by ARCO for effectiveness and
durability.   These  nozzles  are designed  to  seal on standardized
fillpipes.  The modified vapor recovery nozzles  incorporate a
pressure relief valve, which is located at the vapor  return  exit  or
cast  into  the nozzle body, which  is designed  to  open at  approxi-
mately 14-17  in.  water  pressure*,  thereby  permitting  the nozzle
to  refuel  onboard control  vehicles  and  in-use  vehicles.  Nozzle
durability data  are  very limited but one nozzle  has been  inserted
and  latched  7500 times,   representative  of  a  year's service at a
high  volume  station,  and showed  a  seal  effectiveness   of  greater
than 99%.

     ARCO  concludes  that  the preferred seal techniques  are either
the  fillpipe  seal method or the  combination fillpipe/nozzle  seal.
  Refueling  loss  control systems designed  by Exxon and Mobil  are
  designed to operate at fill pressures of less than 4 in.  of water
  pressure.

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                                 -16-
No statements are made  as to the desired  location of the pressure*
relief mechanism.

     2.   Vehicle Manufacturer Comments

General Motors

     GM's March 1978 submission to EPA, Ref. 5,  presents a summary
of their work on the control of diurnal evaporative  emissions and
refueling  losses  through  the  use  of  fuel  tank  bladders.   Their
information  represents   the  most complete study  of  bladder  tank
feasibility known to EPA.  Regarding  bladder  tank feasibility,  GM
admits bladder tanks have the potential for a substantial amount of
emissions control, but  they  are of the opinion  that  the technical
problems which must  be  solved before bladder  tanks are capable of
demonstrating the  same   degree  of  control  effectiveness  as  carbon
adsorption systems,  do  not permit this technology to  be considered
applicable in the  same   time  frame  as  the  other  candidate control
technologies, including Stage  II  control  methods.   The  March  15
submission states that  the major problem with controlling evapora-
tive and refueling emissions with the bladder tank is the formation
of gasoline  vapor mixtures  from dissolved  air  in gasoline.   The
temperature at which the vapor pressure of the dissolved air equals
the partial  pressure of air in  the vapor  space  (bubble formation)
is known to  be  very sensitive to the  quantity of dissolved  air- in
gasoline.   Other design problems  include  pressure  relief valves,
and a puncture resistant fuel gaging indicator.

     The March,  1978 submission presents calculations showing that
the additional  weight  of the components of an onboard control
system  would cancel  out any  potential  energy saving  which would
result from the combustion of the refueling vapors.

     The June, 1978  submission,  Ref. 6,  is basically  a cost effec-
tiveness study  comparing onboard and  Stage II cost effectiveness.

     GM's  March, 1978   submission  estimates  the  cost  of typical
carbon  adsorption  onboard control  systems  to range from $11  for
single canister  systems, to  $15 for two-canister  systems.   The GM
estimates represent  costs  to  the consumer.  The June, 1978 submis-
sion  indicates  that  these figures  must  be increased by $5-$9  per
vehicle  to  cover the costs for  an  enlarged vapor/liquid separator
and additional  carbon.   Thus,  GM's estimates are  now  $16-$24  per
vehicle.   These  estimates do not include  costs  for fillpipe seals
or pressure  reliefs  as  GM assumes  that this hardware would be part
of the service station  fuel dispensing equipment.

     GM  has  stated  that both onboard  and  service station controls
are technically  feasible methods of reducing  refueling loss emis-
sions.   However,  GM's cost effectiveness calculations find onboard
controls to  be much less cost  effective  than Stage  II vapor  re-

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                                -17-
covery.    Rather,  GM  emphasizes  certain technical  concerns  which
they say  are  not  fully addressed by the API  study.   According to
GM, these  include API's  unsubstantiated  support  for  the  onboard
fillpipe  seal and  pressure  relief  (lack  of  adequate  durability
results), an unknown CO penalty for light-duty vehicles (no sensi-
tivity  data  relating  CO  to  test procedure differences),  and  un-
proven feasibility for trucks. .

     GM  is of the opinion that  accelerated  laboratory durability
tests are  not sufficient  to prove  that proposed  elastomer  type
seals will  be effective  in the  extreme usage  and environmental
conditions of the real  world,  particularly when  considering  a  ten
year average  lifetime  for  a light-duty vehicle.

Ford

     Ford has submitted  test  results   from  four 1978 model  year
vehicles (three non-feedback systems and one  feedback  control
system)   modified  for  refueling  loss control.  These  vehicles  are
described in detail  in Table A-4  in  the Appendix and in  their
submission to EPA,  Ref. 7.   The purge  control  systems  for  these
vehicles are  shown in  Figures A-7  and A-8 in the Appendix.

     Ford estimates  the cost  to the  consumer of onboard controls to
range from $15-$20.   They note that the $15-$20  estimate does  not
include   additional  expense  for  such  items  as:   packaging costs,
incremental   labor  costs, or  the  costs for  additional  exhaust
emission control, such  as feedback control over  a  wider air/fuel
ratio range.

     Recent  Ford material,  Ref.  12,   suggest that  the  cost of
onboard systems may  range from  $30 to $253.   The $30 estimate
includes costs over the original $15-20 estimate, including  costs
for such items as  vehicle  modifications  to package onboard systems,
incremental assembly,  and  material substitution.  The $253 estimate
includes the  cost  for a feedback fuel  system  and electronic con-
trols for vehicles which are not  planned to be equipped with these
control devices.

     On  the basis of their in-house test results, Ford has conclu-
ded that onboard  controls are  not technically feasible for light-
duty vehicles.

American Motors

     AMC has   submitted a letter to EPA, Ref.  9, which states their
concerns with the possible  use  of  onboard  controls.   They  state
that  packaging concerns, reduced  quantities of purge air from.
downsized engines,  and  compliance with stringent evaporative
emission standards  are  unresolved  technical  issues  which have  not
been addressed by the  API  work  to  date.

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                                 -18-
     AMC does not find that API has demonstrated light-duty vehicle
technical feasibility.

IV.  Analysis of Available Information

     1.   API Work

Exxon

     Exxon R&E  appears  to have done  a  credible job in  character-
izing  the components  of a hydrocarbon adsorption system.   An
examination of  the  results  from baseline tests and tests with the
modified Pinto  (3-way •»• feedback carburetor system) show small but
finite  increases  in  engine-out  (14Z) and tailpipe  (8Z) CO emis-
sions.  HC,  CO,  and NOx emissions are still well  below  statuatory
emission levels for low mileage vehicles.  Engine-out CO emissions
from the  Caprice are approximately  20Z  higher than baseline test
results; tailpipe  CO  emissions are  approximately  10Z higher than
the  baseline  results.   No increase  in tailpipe  CO  was observed
during tests with the Chevette.  Exxon suggests that differences  in
CO emissions  for  the  Caprice  and the Pinto can  be further reduced
by minor modifications to the  refueling  loss control system or the
exhaust emission control  system, although this has not been demon-
strated.

     Figure  A-2  shows canister  purge as  a  function  of  time.
Although the  data  are  bench   test  results,  the  results are also
representative of actual control system purge  data. It  is signifi-
cant to note that the refueling loss canister  is essentially purged
to  its working capacity after three LA-4  driving.days.   This
implies that  the  refueling  control/exhaust emission interaction  is
likely to be  less in  a  typical driving day than Exxon has measured
using  conservative  test  methods,  which required running  a cold
start FTP immediately after a  90Z refueling.

     ECTD expects that  refueling loss control systems will result
in  slightly  higher CO  feedgas levels.   Exxon estimates that the
average increases in  CO feedgas between  refuelings will  be approx-
imately SZ  for  non-feedback control  systems  and less  than 3Z for
feedback control systems.   ECTD has no other data concerning either
the  magnitude of the average  CO  feedgas penalty  or the resulting
effect on catalyst durability.  It is ECTD'a opinion that the Exxon
estimates are reasonable and  that  these  additional  CO  penalties
will make  it  more difficult for vehicle manufacturer's  to certify
some engine/families  to the 3.4 g/mi CO standard.  The  higher  CO
levels  somewhat reduce  the margin  available  to allow for exhaust
system deterioration over 50,000 miles.

     ECTD  finds  that light-duty  vehicles  equipped  with onboard
systems are  capable of  meeting  a 2 gram evaporative emission
standard.

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                                 -19-
     An analysis of the control  effectiveness of benzene emissions
during refueling,  Table  6, indicates  that  charcoal canisters can
control  in  excess  of  99% of  the  uncontrolled  benzene emissions.
Exxon conducted  additional  tests with  the Caprice and Pinto using
indolene test fuel  with a high benzene  content (4.2%).  The  results
from  these  five tests with  the  modified vehicles  support the
earlier  findings — benzene emissions  are controlled  in excess of
99% during refueling.

     Packaging refueling  loss  control  systems  is  a difficult
problem, but  definitely  not  an  insurmontable one.   The refueling
loss canister  is located  behind the rear seat  and above the rear
axle in  the  Caprice,  and  in  the engine compartment of the Pinto.
It  is  Exxon's opinion, and ECTD agrees, that  it  is  possible for
manufacturers  to  locate  a refueling  loss  canister  on downsized
vehicles without major  engine compartment or sheetmetal modifica-
t ions.

     The  feasibility  of  refueling  loss  controls  for light-duty
trucks has not been evaluated  by Exxon, but  they are  of the  opinion
that refueling  loss  control  is  feasible  for  light-duty trucks by
using larger  control  systems   and  more sophisticated  purging con-
trols (refueling loss  control canisters  for  each  tank and/or two
stage purging systems).   It is ECTD's  opinion  that  the control of-
refueling losses from  light-duty trucks needs  to be demonstrated,
especially the ability to comply with  a 2 g evap standard, before
onboard controls are judged to be  effective for these vehicles at
the costs Exxon has estimated.

     Table 8  shows Exxon's detailed manufacturer's  cost estimates
for refueling control  systems  which have two canisters. ECTD  finds
these cost estimates to be  reasonable  for onboard systems designed
to  control  100% of refueling emissions  from  90% fill conditions.
Exxon estimates  the average manufacturer's  cost for  the light-duty
truck  and light-duty vehicle population  to be about  $9.  That
number is derived as follows:

                                  Assumed        %  of
                                Average Cost  Population

One-cansiter vehicles*            $7.88            70
Two-canister vehicles*            $9.38           20

6,000 to 8,500 Ibs. trucks**     $16.00            10
            Weighted average      $9.00
*   Includes light-duty vehicles  and  light-duty trucks under  6000
   GVW - average fuel tank size = 17 gal.
** Average fuel tank size » 35 gal.

The charcoal cost per gallon of  tank volume  is  assumed  to  be  about
$0.20.

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                                 -20-
     The  $9  incremental manufacturer cost may  be translated to  a
consumer  cost estimate  of  $16.20  by multiplying the  manufacturer's
cost estimate by  a  factor  of 1.8  (Ref.  10, EPA Report  "Cost  Esti-
mations  for  Emission Control  Related Components/Systems and Cost
Methodology Description" by Rath  and  Strong, March 1978).  The  1.8
factor is  in  general  agreement with previous EPA studies, such  as
the EPA  Report,  Ref. 11,  "Investigation and Assessment of Light-
Duty Vehicle  Evaporative Emission Sources and Control,"  June  1976,
which  used a manufacturer to consumer  cost  factor of  2.0.    The
$16.20 estimate  is  in good agreement with consumer  cost  estimates
submitted  by  GM  ($16-$24)  and Ford ($15-$20).   It  is possible  to
further  reduce the  cost of an  onboard  system by trading off some
degree of refueling loss control effectiveness.

     Exxon has  designed refueling loss control  systems based  on
conservative  criteria,  and thus a different set of design criteria
will  afford   reductions  in the  cost of onboard control systems.
Texaco has submitted  data  (Figure A-ll)  Ref.  12,  which  relates  the
number of light-duty vehicle  refuelings and the percent of tank
fill.   A reasonable design  criterion  is  to size  the refueling
canisters to control  90%  of nationwide  refueling  emissions.
Calculations  (Figure A-12)  show that 90% control can  be  achieved, .by
designing systems to control 100% of refueling emissions from fills
to  63% of fuel  tank volume.    If onboard  control systems are  d_e-
signed to  control emissions from  refueling to 63% of tank capacity
rather  than   90%  of tank  capacity,  the Exxon  estimate  of  $9  per
vehicle  can be reduced  by  $1.60  as  the  result  of reduced charcoal
quantity.  This cost  reduction  is proportional  to the reduction in
carbon bed volume.  The net effect of this  design change is  a cost
reduction to the consumer of approximately $2.88.   Changes  in
design specifications such as the  90%  fill requirement  may  afford
additional cost  reductions for other control system components  as
well  as  a general  reduction  in  the  problem of  packaging  onboard
control  systems.

     ECTD estimates the consumer cost of light-duty vehicle  onboard
control  systems  designed   for  maximum control  effectiveness  to  be
about $17.  This estimate does not include an estimate for the cost
of the fillpipe seal or pressure relief valve.   The  $17  estimate is
based  on Exxon estimates-,  which when translated to  consumer  costs,
are in agreement  with  consumer cost  estimates  provided by GM  and
Ford.

     Exxon estimates  the   manufacturer's cost  for a  fillpipe seal
and onboard pressure  relief valve to be  approximately $1.50.  ECTD
estimates  the consumer  cost  of an  onboard fillpipe  seal  and  pres-
sure relief to be approximately $2.70.

Mobil

     Comparisons  of  baseline  and  modified vehicle  test  results
indicate  that Mobil R&D is able  to add refueling controls  to  the

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                                 -21-
1978 Pontiac Sunbird  (3-way  * feedback carburetor system) without
adversely affecting exhaust  or  evaporative emissions.   No changes
in engine-out or  tailpipe  CO emissions are observed.  Evaporative
emissions  are also unchanged,  with both baseline and  modified
vehicle  test results near  the 2  g evaportive  emission  level.

     It must  be emphasized, however, that Mobil and Exxon use
different  test  procedures  for  measuring  the  refueling  control/
exhaust emission  interaction.   Mobil's test procedure consists of
the following sequence of events:

     1)   Load  canister  to  approximately  one-half of working
capacity.

     2)   Condition vehicle by  driving two simulated city driving
days (4.7 LA-4's with  one  hour  hot soaks in between and a diurnal
at the end of the  day).

     3)   Drain  fuel tank to  10% of volume.

     4)   Refuel to 90% of volume in SHED.

     5)   Conduct  hot  start emission test.

     6)   Soak vehicle for 11 hrs.

     7)   Conduct  diurnal evaporative test  in SHED.

     8)   FTP

     9)   Hot soak evaporative test in SHED.

     Steps  1, 2,  and  5 are  the important  differences between the
test procedures used  by  Exxon and Mobil.   Mobil  starts their  test
sequence with a canister  loaded to one-half  of working  capacity,
versus a saturated condition for the Exxon  procedure.  Mobil  purges
the refueling loss canister with two LA-4  driving days, versus the
Exxon method of purging by running  a  series  of LA-4 driving  days
until  the  fuel  tank  reaches  10% of  capacity.   Mobil  runs  a hot
start emission test prior to the FTP; no such additional condition-
ing is used in  the Exxon test sequence.  It is  ECTD's opinion  that
the the  Mobil  test sequence,  particularly the addition  of  a hot
start exhaust emission test,  will result in a less severe  refueling
control/exhaust  emission interaction.   This  is  due to the smaller
quantity of hydrocarbon which  is purged during  the cold start FTP
when using  the  Mobil  test sequence.   The  actual emission  sensi-
tivity  to  various  test  procedure  arrangements has  not  yet  been
determined.

Atlantic Richfield Company

     ARCO  states  that the fillpipe  modification  approach and the-

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                                 -22-
combination fillpipe/nozzle  seal  concept are  the  preferred  tech-
niques for  achieving  a no-leak seal.  This  recommendation  is  not
supported from an analysis  of leak  rate and durability data because
the test results show that seal  effectiveness  among all  three
concepts are equal.   Cost estimates for the three designs have not
been  submitted.   ARCO  is  continuing to  collect  field durability
data on their prototypes, but the lack of  a more extensive durabil-
ity demonstration under simulated  conditions  of  real  world  usage
makes it questionable  to assume that  their  seals  will  function as
well in the field as they have  in the  laboratory.

     In particular,  ARCO has not adequately addressed the issue of
onboard pressure relief valves  versus  liquid pressure relief valves
located on  the  fill nozzle.   Pressure relief valves are necessary
to prevent  over-pressurization of  the fuel  tank  in the event of a
failure  of the  automatic  shutoff on the fill  nozzle.  For  the
purpose  of  fuel tank  integrity in the event  of  a vehicle  crash,
NHTSA recommends  that  the  pressure  relief  not be  located on  the
fuel  tank.   However,  a relief valve  might  be incorporated  safely
with  a  fillpipe seal  mechanism,  which would  be  sealed-off by  the
fuel cap during vehicle operation.

     The achievement  of a  safe and durable seal at the nozzle
fillpipe interface  is   critical to the performance  of  an onboard"
refueling  loss  control  system.    ARCO  has demonstrated  that  the
effectiveness  of fillpipe  seals, combination  seals and nozzle
seals are equal; but,  the design,   locations, and durability of the
pressure relief valve have  not  been adequately addressed.

     Conceptually, a pressure  relief may be  designed  to function
properly when located  on the vehicle or on the nozzle.  However, if
refueling losses  are controlled on the  vehicle,  it is recommended
that  the fillpipe/nozzle seal and pressure  relief  valve  also be
located on the vehicle.  Locating all  parts of an onboard system on
the vehicle will prevent the potentially  serious problem of refuel-
ing a controlled vehicle without protection  from overpressurization
(no relief valve).  Administrative  and certification concerns also
suggest  that onboard  controls  are  practical  only  if  the  seal  and
pressure relief are  located onboard.

     An alternative technique of achieving a  seal at the fillpipe/
nozzle interface  is the liquid trap or  submerged fill.  This seal
concept  has not  been  adequately  investigated.   Submerged fill
offers the potential for significant advantages in terms of simpli-
city  of  operation and  durability  (mechanical, magnetic,  or  elas-
tomer type seals are  avoided).   It is  ECTD's  opinion  that  the
submerged fill concept should be investigated.  Submerged fill (and
seal  techniques investigated  by  ARCO)  must  be  evaluated in  the
context  of  a complete  refueling and  evaporative  emission control
system.  This  includes incorporating features to provide adequate
thermal  expansion  capability and   rollover  protection  while  still
permitting normal safe refueling.

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                                 -23-


     2.   Vehicle Manufacturer Information

General Motors
     General Motors has several reservations concerning the appli-
cability of onboard  controls,  citing such things  as:   the uncer-
tainty  of  the  effectiveness  of  fillpipe/nozzle  seals,  potential
cost  increases  associated with  exhaust  emission  control systems
which must be designed to control  increased CO emissions, negative
fuel  penalties  which  are  the  result  of  this  increased emission
control,  and the  long lead time which  is  required to  obtain a
substantial reduction in  atmospheric hydrocarbon and  benzene
loading.  However,  with  the exception  of GM's  concern with using
accelerated laboratory tests to  assess fillpipe/nozzle seal dura-
bility, these reservations  are not detailed in their submissions.
GM  has stated  that refueling losses can be  controlled  on the
vehicle Cfeasibility  for  trucks has not  been  demonstrated)  or at
the service station.   GM's disagreements with controlling refueling
emissions  with onboard controls are primarily based on the issue of
cost/effectiveness.

     GM's  March, 1978 submission to EPA presents a  summary of their
work on the control of diurnal evaporative emissions and refueling
losses using fuel tank bladders.

     It is EPA's opinion that  the theoretical control effectiveness
of  evaporative  and  refueling  loss  emissions  using  bladder  tank
technology is high and that these  problems  can  be solved.   It is
recommended that bladder tank  feasibility be researched by funding
a bladder tank hardware demonstration contract.

     The March, 1978  submission  presents  calculations showing  that
the  additional weight of the components  of  an  onboard control
system  will  cancel out any potential  energy saving which results
from  the  combustion of the refueling vapors.     ECTD agrees  with
this analysis.

     The June,  1978 submission  is  basically  a cost effectiveness
analysis comparing onboard controls with Stage  II controls  (balance
displacement and vacuum assist  systems).  GM estimates  that onboard
control systems,  effective with  the  1982 model  year,  will range
from $16 to $24.   These figures  are about $5 to  $9 higher  than the
March,  1978 estimates due to higher estimates  for  larger  canisters
and a  new vapor/liquid separator.   GM  assumes  that the seal  at the
fillpipe/nozzle  interface  will  be obtained using modified vapor
recovery nozzles.  GM does not include  seal costs  in  its  estimate.
They  assume  these costs will  be the  same  for  either  Stage II or
onboard controls and, hence, leave  these  costs out of their  analys-
sis  of both  options.   General Motor's onboard cost estimates are
costs  to  the consumer.   These  estimates are based  on  cost? for
hydrocarbon  adsorption  systems  which  control   evaporative and
refueling emissions with one canister  (cheapest) and systems which

-------
                                 -24-
use two separate canisters for containing evaporative  (diurnal and
hot soak)  and  refueling emissions (most expensive).   The GM cost
estimates are consistent with Exxon's manufacturers cost  estimates
for onboard  controls.    As discussed  earlier,  it  is  possible to
design cheaper refueling loss  control systems  by not providing 100%
control of refueling emissions under  worst case conditions.  If the
design criterion of 100% control for a 90% refueling is changed to
100%  control  for a.  63% refueling,  it  is possible to reduce the
required working capacity  of the charcoal canister, thus reducing
the average system cost to  the consumer  by about $3.00.

     GM does not  find  that onboard  controls  are  feasible for the
1982  model year,   although their  cost effectiveness  analysis
calculations are based  on the  assumption that  onboard control could
become effective beginning with the  1982 model year.   It  is ECTD's
opinion that onboard refueling loss  controls  cannot be implemented
prior to 1983 model year.  GM did  not  comment on  the feasiblity of
refueling loss  control's  for light-duty trucks and heavy-duty
gasoline powered vehicles.

Ford

     Ford  emphasizes   that the  refueling  loss/exhaust  emissions
interaction is  a  function  of the  test procedure and  that the
differences between  emissions interactions measured by Exxon and
Mobil  are  due  to test  procedure differences.   This   statement is
correct,  although  the actual  emission  sensitivity  to  the test
procedure is unknown.

     Ford attributes the high CO effects, which they have observed
with  both  conventional  oxidation catalyst  systems  and  three-way
plus feedback carburetor systems,  to  the presence  of refueling  loss
controls.  However, the reason  for their high CO  emissions is due
to  a  non-optimally designed system for  controlling the hydrocarbon
purge  rate.  Ford  uses a manifold vacuum controlled purge  system,
which  results  in cold  start  hydrocarbon  loadings  that are two to
three  times higher than  results obtained  with venturi  vacuum
controlled systems  (Exxon  system).   This  is the  reason  the Ford
results  are  so high,  particularly engine-out CO emissions.  Ford
maintains that refueling loss control systems produce  peak  enrich-
ment  effects  equal to  two air/fuel ratios,  which is beyond the
capability  of  their current  feedback  carburetor control  system.
Exxon has  demonstrated, however,  that venturi vacuum maintains the
air/fuel ratio  within  the control  limits  of the  feedback  control
system.   Problems  with the existing Ford feedback control  system
are likely to be the result of  response  time  problems, not  control
range problems.

     Some  of  Ford's concerns with onboard  refueling  control  sys-
tems,  such as packaging, weight of onboard systems, and the design
of  vapor/liquid  separators have been examined during the  API  study
and shown not to be significant problem areas.  Other concerns with

-------
                                 -25-.
onboard controls,  including  system durability,  onboard feasiblity
for  light  and heavy  duty  trucks, and  high  altitude feasibility,
have  not  been  adequately  addressed  in any of  the information
submitted to  ECTD.   It remains ECTD's  judgment that these issues
need  further  examination, particularly before onboard controls are
determined to be feasible  for  light  and heavy-duty trucks.   Al-
though onboard durability data  are not  available,  ECTD finds  that
onboard control  systems should  be  as durable as current evaporative
emissions  control  systems, which last for the  lifetime  of the
vehicle.

     Ford estimates  the  consumer cost of onboard controls for
light-duty vehicles to range from $30 to $253.   EPA estimates that
the  consumer  cost of  onboard  control  systems  will be about $20
(includes  $2.70 for the cost of an  onboard  seal and pressure
relief).

American Motors

     AMC's concerns with the use of onboard controls are addressed
to  the  issues of exhaust and  evaporative  emissions interactions,
feasiblity of vehicles  using small engines,  costs, and light-duty
truck  feasibility.   With the  exception  of  feasibility for light-
duty trucks,  AMC's concerns  have been examined in detail by the API
study.  EPA's analysis of that  data is that refueling loss controls
are feasible for light-duty  vehicles aC  a consumer  cost of approxi-
mately $17.

V.   Conclusions
Feasibility

     An  Analysis of  the  available  informatio-n  has shown  that
onboard refueling loss  controls  are  feasible  for light-duty
vehicles  designed  to  meet low  exhaust and  evaporative  emission
standards (0.41 HC, 3.4 CO,  1.0  NOx and 2.0 Evap.).  However, the
feasibility for light-duty trucks, particularly the assurance that
onboard  control  systems  are compatible with  a  2 gram evaporative
emission standard, has  not been established.   Feasibility for
heavy-duty gasoline vehicles has  not  been established.  tf

     An  analysis  of  information and  test  data presented  to EPA
regarding the  control of  light-duty  vehicle  refueling  emissions
offers the following conclusions:

     1.   Onboard control systems in  laboratory use situations can
control  in excess of  97% of the  uncontrolled hydrocarbon refueling
losses.

     2.   The same systems  in  laboratory use situations can control
in  excess  of  97%  of  the  uncontrolled benzene  refueling  losses.

-------
                                 -26-
     3.   Test results  from  two light-duty vehicles  equipped with
three-way catalysts, feedback carburetors,  and  prototype  refueling
loss systems  show  that  tailpipe CO emissions range from  a 0 to  8%
increase.

     Test results  from  the  same vehicles  show that  engine-out  CO
emissions range from a 0 to 14%  increase.

     4.   Emission  data from two  conventional  oxidation  catalyst
equipped light-duty vehicles  show that  tailpipe  CO  emissions
range from a 0 to 10Z increase.

     Data from one  of the  conventional  oxidation  catalyst vehicles
show that engine-out CO  emissions increase by 10 to 20Z.

     5.   The  addition  of refueling loss  controls  to  light-duty
vehicles does not significantly  affect evaporative emission  losses.

     6.   Minor  increases  in CO  exhaust  emissions  seen for some
vehicles can  probably be  controlled  by minor change  to either the
refueling loss  control  system  or  to the  exhaust  emission  control.
system.   However,  the  addition  of refueling  loss  controls will
likely make  it more difficult  to certify some  vehicles  to the 3.4
g/mi standard at 50,000  miles.

     7.   Onboard  controls  do  not  affect vehicle  fuel  economy.

     8.   Onboard  controls  do  not  affect  vehicle  driveability.

     9.   Refueling  loss  control  systems  for  light-duty vehicles
are  estimated to add $17  -to the vehicle  sticker price.   The $17
estimate does  not  include the costs associated with  the  fillpipe/
nozzle seal or pressure relief  valve.   The  consumer cost  of  a seal
and pressure relief in the fillpipe is estimated to be about  $2.70.
The cost of a seal  on the  nozzle  should be roughly the same  as the
cost for  a  Stage II nozzle.  However,  it  is recommended that all
components of an onboard control system be  located on the vehicle.

Lead time

     Onboard  refueling  loss  control  can  be  implemented for 1983
model  year  light-duty  vehicles,  provided  that  potential  problem
areas  such  as  the  design and  development  of  effective  fillpipe/
nozzle seals  and pressure relief valves do not require  additional
hardware demonstration  programs.   It is  anticipated that the
fillpipe/nozzle  seal and  the  control  feasibility  for   light and
heavy-duty trucks are issues which can  be  resolved during the NPRM
process.

     ECTD estimates  that  a minimum of two years  lead  time will  be
required by  manufacturers  for development  (purge  system  optimiza-

-------
                                        -27-
             Quarter;

Develop Certification
Test Procedure

Continued Study of
Fillpipe/Nozzle Seal
Concepts

Decision on Seal
Concepts

EIS, EIA, NPKM
Preparation

Publish NPRM

Final Rule

Manufacturers
Lead Time
         Figure  1

        Lead  Time

                      Calendar  Tear
         1979      1980      1981
I34I1234I1234I1234
 1982
1234
 1983
12341
          (Decision to publish service  station nozzle
           requirements or put seal on  vehicle)
                                                1983 MY

-------
                                 -28-
tion,  design  and  verification  of  fillpipe  seal  mechanisms)  and
production tooling changes  (tooling  associated with fabrication and
relocation of new evaporative  control components).  These estimates
are based in  part  upon  data  provided  by manufacturers relating to
carburetor tooling changes, and  in  part upon data supplied  by GM
relating to  retooling  changes  for body panel  modifications.
Additional time  will  be  required  for EPA to develop a certification
type test procedure and issue regulations, however, the certifica-
tion procedure development can overlap the production tooling lead
time.  Therefore,  the projection  is that  an  NPRM can be published
late in 1979 with final  rules  promulgated by 1980 with the earliest
possible  implementation date  being 1983.   (See lead  time chart,
Figure 1).

Compliance Costs

     ECTD estimates that certifying  light-duty vehicles for compli-
ance with a refueling  loss  standard will require  an additonal
one-half person-year  at  the EPA-MVEL.  This is based on an estimate
of 100-150 refueling  loss tests per year.   Facility modifications/
equipment procurements will cost  from $30K  to $80K.

     A potentially significant impact on refueling loss compliance
costs  is Inspection/Maintenance  testing  of  light-duty  vehicles.
EPA has  not  developed,  and is not  aware of, a  valid  I/M test for
determining the  performance  of evaporative emission  control sys-
tems.  Monitoring the performance of in-use refueling loss control
systems will be difficult  and cumbersome.   At this time, it may be
assumed  that  the onboard  compliance costs associated  with an I/M
test will be equal to the  cost of  Stage  II  enforcement.

VI.  Recommendations  for Future Work

     1.   ECTD  recommends that  additional  hardware testing be
conducted to determine the  optimal fillpipe-nozzle seal.  Addition-
ally, the operation and  durability of a  fillpipe or nozzle pressure
relief must  be  demonstrated.   The  use  of an  onboard liquid trap
seal  (submerged  fill)  as  an  alternative  to elastomer  type  seals
should be investigated.

     2.   ECTD  recommends that  additional  hardware testing be
conducted to assess the  feasibility  of controlling refueling losses
on  light-duty  trucks and heavy-duty  gasoline  powered  trucks.

     3.   ECTD recommends  that the  need for  controlling refueling
losses  from  diesel powered vehicles  be investigated  since  these
vehicles  are  predicted to  represent a  substantial  fraction of the
entire motor vehicle  population in the 1980's.

     4.   ECTD recommends   that  the  bladder fuel  tank be investi-
gated  as an  alternative  to  carbon  adsorption  technology.   It
is ECTD's opinion  that  the theoretical  control  of evaporative and

-------
                                -29-
refueling  loss emissions  with bladder  tanks is high  and  that
technical  problems  can  be  solved.   It  is  recommended that bladder
tanks feasibility be researched  by  funding a hardware demonstration
contract.

     5.    Finally,  ECTD recommends that  methods  of  reducing the
cost  of  onboard refueling control systems  be examined.   Such
studies  should be directed toward tradeoffs between  level of
control  effectiveness and  cost.   It may be possible to  sacrifice
control  capacity  that is required under only infrequent conditions
to  achieve  a  proportionally  more  significant  cost  savings.

-------
                            Bibliography
 1.   "Control  of Refueling Emissions," Statement by General Motors
     Corporation, June 11, 1973.

 2.   "Control of  Refueling  Emissions  with an  Activated Carbon
     Canister  on the Vehicle  -  Performance  and Cost Effectiveness
     Analysis,"  Interim  Report  Project  EF-14,  prepared  for  the
     American  Petroleum  Institute,  Washington,  D.C., October 1973.

 3.   "On-Board Control of Vehicle  Refueling Emissions - Demonstra-
     tion of Feasibility," API Publication No.  4306, October 1978.

 4.   "Summary  and Analysis of  Data from Gasoline Temperature Survey
     Conducted at  Service  Stations," Radian Corporation,  Austin,
     Texas.   Prepared for  the American  Petroleum Institute,  Wash-
     ington, D.C.,  November 1976.

 5.   "General  Motors  Commentary to  the  Environmental  Protection
     Agency Relative to  On-Board Control of  Vehicle Refueling
     Emissions," March 1978.

 6.   "Suppplement to  General Motors Commentary to the Environmental
     Protection  Agency  Relative to  On-Board  Control of  Vehicle
     Refueling Emissions," June  1978.

 7.   "Ford Motor Company  Response to EPA Concerning Feasibility and
     Desirability  of  a  Vehicle On-Board  Gasoline  Vapor  Recovery
     System."

 8.   "Ford  Motor  Company Position  Concerning Feasibility  and
     Desirability  of Vehicle On-board Refueling Vapor Control
     Systems," November 6,  1978.

 9.   AMC letter  to  Paul Stolpman, August 3, 1978.

10.   "Cost Estimations for Emission Control Related Components/Sys-
     tems and Cost  Methodology Descriptions,"  Rath and  Strong,
     Inc., Lexington, Massachusetts.    Prepared for  the  Environ-
     mental  Protection Agency,  Ann  Arbor,  Michigan, March  1978.

11.   "Investigation and  Assessment of Light-Duty Vehicle  Evapora-
     tive Emission  Sources  and  Control," Exxon  Research  and
     Engineering Company, Linden,  New Jersey.    Prepared  for  the
     Environmental  Protection  Agency,  June 1976.

12.   Texaco  statement submitted to  Paul Stolpman,  July  18,  1978.

-------
                              APPENDIX A-l
     The Appendix contains detailed descriptions and data from  the
test vehicles and fillpipe/nozzle seals  which were  used  in the most
recent  testing  and  evaluation of  refueling loss  control systems.

Exxon

     Table A-l  presents  a description of all Exxon test vehicles.
Figure A-l is a  schematic of  the basic  control  system designed  for
the Chevrolet Caprice and the Ford Pinto.   The  refueling emissions
(RCS)  canister  controls  both  refueling  emissions and  diurnal
evaporative  emissions;  the  evaporative  emissions  (ECS)  canister
controls carburetor  hot  soak losses.   Exxon investigated  several
different  purge  mechanisms,  including combinations  of  manifold
vacuum and venturi  vacuum,  and two stage purge control  valves
controlled by  fuel  volume,  but  venturi  vacuum,  which  is  propor-
tional  to  engine air flow, is the  most effective purging  method.
Exxon's control  system is designed to maintain  the total purge  air
volume  (RSC  +  ECS)   equal  to  the purge  air volume of  the  unmodi-
fied vehicle's  evaporative control system.

     The air bleed control valve, shown  in Figure A-l,  is necessary
because the RCS  canitser  is purged more efficiently  (higher hydro-
carbon purge  per unit volume  of  air)  than  the unmodified ESC
system, thereby  resulting in  richer  A/F mixtures.   This air bleed
may not  be necessary for  other  vehicles with  feedback carburetor
controls.

     Figure A-2 is a plot of the  RCS canister  purging as a. function
of  time.   These data are based  on consecutive LA-4 driving days.
As  noted,  the  RCS system is  purged  at  a  rate  of  about 4  litres/
min., which corresponds to  a  total  canister purge volume of about
40 litres during an  LA-4  driving  cycle.

Mobil

     Specifications  for the vehicle Mobil  has modified  for  refuel-
ing loss control are summarized as follows:

     Vehicle:  1978  California Pontiac Sunbird

     Engine Size:  151 cu. in. L-4

     Interia Weight:   3000 Ibs.

     Emission Control System:
          Exhaust:      3-way catalyst  with  feedback  carburetor,
                       EGR
          Evaporative:  Carbon canister

-------
                                 A-2
     Fuel Tank Capacity:   18.5 gallons

     The production vehicle  is modified for controlling refueling
emissions by enlarging the existing carbon canister,  (one canister
controls  refueling,  diurnal,  and hot  soak loss),  enlarging the
vapor line between  fuel  tank and canister,  redesigning the vapor/
liquid  separator,  and  installing a purge  control orifice between
the  canister  and intake manifold.   A  schematic  of the Sunbird's
control system  is  shown  in Figure A-3.   Various  flow  control
orifices were inserted in the  canister purge line but best results
are  obtained  with  an orifice  of 0.100  in. diameter.   Mobil uses
1550 grams of Calgon BPL-F3 carbon for  their control  system, which
assumes a 20Z safety factor.   This quantity  of  carbon  is based on a.
90% fill of the 18.5 gallon tank,  and assumes a hydrocarbon loading
of six grams per gallon  of dispensed fuel.   The working capacity of
the canister is  approximately  240 grams.   The basic  components of
the canister  control  system are  shown  in Figure  A-4.  The ported
vacuum purge control valve is from a 1978 Chevrolet  Impala evapora-
tive  canister,  while the  two fuel tank vapor  valves  (two are
used  to reduce the pressure  drop during the  refueling operation)
are carburetor bowl valves from a 1978  Impala.  Using  two fuel tank
vapor valves results in fillpipe  pressures as  low as  two inches of
water pressure during refueling.   The  fuel  tank  vapor valves are
also  controlled by manifold  vacuum such  that  the  vapor valves
are  closed  when  manifold vacuum  is  present at  the control  port.

Atlantic Richfield Company

     Figure A-5  shows  the fillpipe seal which ARCO has developed
and tested for durability.   Tables A-2 and A-3 are typical of the
durability results obtained  with this seal.  Figure A-6 is an
example of a  prototype  combination fillpipe/nozzle seal which has
been developed and evaluated by ARCO.

Ford

     The vehicles  which  Ford  has  used  for  refueling loss testing
are  shown  in  Table A-4.   A  single 4.35 1  canister is used in the
Mustang, while a duel canister system,  829  ml and  3.4  1, are used
for  controlling  carburetor  vapors and diurnal/refueling losses,
respectively,  in the Pinto.  The  purge  systems for  the Mustang and
the Pinto are shown in figures A-7 and  A-8.

     Figures A-9 and A-10 are plots of  canister loading  versus test
procedure  sequence.   These  plots indicate  that  Ford's refueling
loss  control system is quite sensitive to  the particular test
procedure which  is  used  to quantify the refueling  control/exhaust
emission interaction.

-------
                                      A-3
                                    Table A-l

                              Vehicle Descriptions
   Make
Model
Engine Displacement/
    Configuration
Control Systems
Fuel Tank
Capacity
(gallons)
Chevrolet   Caprice    5.0 litre (305 CID)/V-8

Ford        Pinto      2.3 litre (140 CID)/L-4


Plymouth    Volare     3.7 litre (225 CID)/L-6

Chevrolet   Chevette   1.6 litre (98  CID)/L-4
                                     Ox. Cat., AIR, EGR

                                     3-Way, Ox. Cat.,
                                        AIR, EGR

                                     Ox. Cat., AIR, EGR

                                     Ox. Cat., AIR, EGR
                                                     21.0

                                                     13.0


                                                     18.0

                                                     12.5

-------
                            Table A-2
                       FILLPIPE MODIFICATION
                        ROTARY SEAL-CR  7538
                      LEAK RATE AS AFFECTED BY
                     FILLNECK PRESSURE AND WEAR
NO. OF SPODT
INSERTIONS
0
100
100
100
100
100
• 100
100
100
100
100
TYPE
SPOUT

Smooth
Rough
Smooth
Rough
Smooth
Rough
Smooth
Rough
Smooth
Rough
CUMULATIVE
INSERTIONS
0
100
200
300
400
500
600
700**
800
900
1000
FT3/MIN
@ 5" W.C.
0
0
0
0
0
0
0
0
0
0
0
LEAK *
@ 15" W.C
0.001
0.001
0.001
0.001
:, o.ooi
_ 0.001
0.001
0.001
0.002
0.002
0.002
*  Leak rate average of six nozzle insertions.

** Expected number of insertions during vehicle life.
RGJ:ip
7/13/78

-------
                         Table A-3
                   FILLPIPE MODIFICATION
                    ROTARY SEAL-CR 7538
             EFFECT OF LIQUID AND VAPOR GASOLINE

               SOAK ON SEAL ID AND LEAK RATE*
HOURS OF
LIQUID
SOAK

    0

   16

   35
TOTAL WEEKS
OF VAPOR
SOAK










0
0
0
2
3
4
5
6
7
8
SEAL
IDrIN.
.712
.712
.711
.705
.699
.701
.703
.698
.693
.691
FT3/MIN
@ 5" WC
0
0
0
0
0
0
.001
0
0
.001
LEAK**
3 15" WC
0
0
0
0
.001
.001
.001
0
.001
.002
*  Vapor and liquid soak at 72°F.

** Leak rate average of nine nozzle insertions.
RGJ:ip
7/13/78

-------
                              Figure A-l


EVAPORATIVE AND  REFUELING EMISSIONS CONTROL SYSTEMS
      REFUELING AND
      DIURNAL VAPORS
                         PURGE
                         CONTROL
                         VALVE
                      RESTRICTION
                                          CONTROL VACUUM
                      CARBURETOR VACUUM PURGE


                 RESTRICTION


                 VENT
                                                   CARBURETOR BOW
AIR BLEED
CONTROL
VALVE
                                                     MANFOLD VACUUM
                                                         PURGE
                                                                ECS CANISTER
          REFUELING EMISSIONS
           CONTROL CANISTER

-------
                                  - 8 -
carburetion, a. technology expected to appear in most cars after 1981


to meet tailpipe emission standards.


          On-board control systems have been installed on the Caprice


and on the Pinto.


Systems on the Caprice and Pinto


          Figure 4 shows a diagram of the RCS and ECS systems installed


in the Caprice and the Pinto.


          The RCS canisters are cylindrical two-pass containers with


vertical vents.  Purging is conducted in the direction opposite to the


adsorption of hydrocarbons (countercurrent).  The Caprice and the Pinto


contain approximately 1800 g (5.0 £,) and 1100 g (3.0 &) of Calgon


BPL-F3 activated charcoal correspondingly.  This carbon is currently


being used in the Ford ECS canisters.  The RCS canisters are designed


to trap all losses from the fuel tank:  diurnal losses and refueling


losses.  In the modified cars, the ECS canister is dedicated to trap


carburetor bowl emissions only.  Since the diurnal vapors are no longer


directed to the ECS canister, restrictions were added to the ECS purge


lines to reduce  the purge rate and  thus the air intake to the engine due


to canister purging.


          The RCS canister is purged by vacuum generated by the air


venturi at the carburetor throat.   Taps were drilled  in the carburetor

                               **
for  that purpose.  Carburetor venturi allows purging  at a rate proportional


to the power-output of  the engine.


          To prevent purging during a. cold start, when the catalyst, is


cold, purge control valves which are opened by control  (ported) vacuum.


are  installed  on the RCS purge lines.  The ported vaccuin signal operates

-------
                                    Figure A-2
                                                      PURGE @ 4 LITRE/MIN. WITH DIURNAL ADDITIONS

                                                         ADSORPTION TO 35 g. FROM BREAKTHROUGH

                                                             3.5 litre Canister (BPL-F3)
    320
    300
    280
1 1 LA-4 » 40 litres » 10 min. DD
L 5 LA-4'a » 1DD» 50 min. L
1
\ >
-\ 6
GRAMS
Purged Diurnal
89 11
34 14
29 20
32 22
32 24
33
"od
~

n
u
4-i
V)
•r4

«


c
o
    260
    240
, 0)


i J  220

:' 3
   200
   180
   160
                                                                                                       lst
                                                                                                                              g.
                                                                                                                      158 g
                                                                                                                      capacity
1 1
™ 60
1
90
i
120
i
150
i
180
i i i
210 240 270

-------
                        i                  Figure A-3

                    ONBOARD  SYSTEM TO  CONTROL  REFUELING EMISSIONS
    Control
    Vacuum'
     Lines
Flow Control
  Valves
                                       Carburetor
                                                     Intake Manifold
   Carburetor  Bowl Vent
Engine
                                       Canister Purge Line
                                     With Flow Control Orifice


                                       Fuel Tank Vapor Line
                 Vapor-Liquid
                  Separator
                                         (5/8" l.D.)
             Carbon Canister (4.4 L)
Sealing
Nozzle
                        Fuel Tank

-------
                                                Figure   A-A

                                   Refueling  System  Carbon  Canister
  Sunbird
Carb.  Bowl
  Fitting
 Chevy Purge
Valve,  Drilled
   To 0.180"
                                                              Carbon
                                                                        //////// / / /I/ / / / / // -l/8" Plexiglass
• T'dla. x!3/4" long
    Plexiglass Tube

-------
             Figure A-5
  FILL  PIPE  MODIFICATIONS
  ROTARY SEAL
                   ROTARY SEAL
  TRAP DOOR
           LEAD RESTRICTOR
FILL PIPE  MODIFICATIONS
ROTARY SEAL
TRAP DOOR
                                          SPOUT
         LEAD RESTRICTOR

-------
           Figure  A-6
NOZZLE / F1LLPIPE MODIFICATION

CONE SEAL

 LEAD RESTRICTOR
 TRAP DOOR
SPOUT
                          DISK
                                    LATCH COLLAR
        CONICAL SEAL
NOZZLE / F1LLP1PE MODIFICATION

CONE SEAL

LEAD RESTRICTOR
TRAP DOOR
SPOUT
                                    LATCH COLLAR
        CONICAL SEAL

-------
                                       ON BOARD VAPdJTRECOVERY SYSTEM
VACUUM ACTUATED PURGE
VALVE AND TANK VAPOR
INLET VALVES ARE SIMILAR
TO CURRENT PURGE VALVES
                       Mustang 8Z18 &  8Z19
                             System A
TANK VAPOR INLET VALVES
VACUUM CLOSED
                                       PURGE VALVE WITH
                                       0.180 IN ORIFICE
                                       VACUUM OPEN
                                                                             SERVICE STATION
                                                                               NOZZLE
                                                                        FILL PIPE OPENING
                           THIS VALVE CONTAINS
                           A  .OV? IN. BY-PASS
                           .ORIFICE FOR TANK RUNNING
                           LOSES
                                          GARB BOWL
                                          VENT CONNECTION
   PURGE LINE TO
   PCV HOSE
GARB BOWL
VENT LINE
                          PURGE SIGNAL
TANK VAPOR
LINE      7
                                               TUBING
                               (REPLACES CONVENTIONAL
                               TUBING)
                           •tf350 ML CARBON VOLUME
                            OPEN CELL FOAM
                            WIRE SCREEN

                            FIBERGLASS    '
          8 IN.
          DIA
        CANISTER (REPLACES CONVENTIONAL CANISTER)
ENGINE COMPARTMENT MOUNTED
                                                                                 FUEL TANK
                                                                                                              £

-------
                          UN BUAK1J VA
                               PINTO 8E79 & 8E12H
                                   System B
                                   PURGE LINE TO PGV HOSE

                            GARB BOWL VENT LINE
VAPOR PURGE
TO PCV LINE   (
THRU BOTH .090"
& .085" ORIFICES
                                      PURGE SIGNAL

                                         i PURGE LINE
     PURGE
     SIGNAL
   .085"
   (PROD. VLV.)
\.090" REMOTE PURGE VLV.
                                3»*00 ML CARBON VOL
  925 ML CARBON VOL. '

                                                   I/
                                                 ATMOS.
                                                        TANK VAPOR
                                                        LINE
                                                                              FILL PIPE
                                                                    FUEL TANK
                                                                                                  "8
                                                                                                  H
                                                                                                  ID.
                                                                                                  oo

-------
(•
                               Procedure #2 Set 2
                          •   Mustang 5.CL  (8218) 1973 1*9 States
                                 Date 7-17-73 Test 29                .       .
                   U350 nl  Canister, Tank St Garb. Ecwl w/.lSO" Purge  Orifice,
                         |    Grass of Vapor Purged (-)j Absorbed  (+)
                                                       'Figure  A-9
            I +55  I  -98 I +27  1 -50  1  +35 I  -38 I +39  1+8   I.+95
  ' -1*6
•1
 X
 si

 St.
 £
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 •P
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 |

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                                                  I  -7«f 1  +18 !

                                                         Productic:
                                  	^          "   .Feedgas
                                                 Gas7iS~CO         "  15.9
                                 ON BOARD SIS.   Bag 1,23:3 CO Gas.     205
                                	Bag 1 CO C-ss.       1  1^3
                                                 Bag 1 CO- Gcs.       I   05
                                 BASELIJS SB.   Bag 1,243 CO Gas.  •   118
                                                        CO             9A
               r-f O
           r-i   r-l S
           Cj   «H 3
           •H   t< n
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^  -
         01
             C
             o ._
             n 3
             00  I
                                                                         a
s
o
                                                               o
                                     Test Sequence

-------
M
-1 116
 t,
 01
•p
o

•a
o
        I   1
                                                         .       .
                i  •  '    Procedure #3  3et 2             .                  ;
                •  Muatang 5.0L (8Z19) 19?8 1*9 States                !   •   '      '
                !       Date 7-8 & 9-78 Tost //l»f, 15     :      '      '   :   '
                    H350 ml Canlater, Tank & Garb. Bowl Vapora w/,180" Purge Orifice
                    I Grains of vapor,  Purged (-), Absorbed  (+)
              I +30 I  -33 I  r?7 I -**5 1+22  14-3   I -1?  ! +13  I     >
              t     t     t  :   t     t    t  '>    t    t
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+>
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                                                                                              CO
                                                                                                             ,

                                                                                                            •s
                                                                                                            M
                                                                                                            (D
                        Teut Sequonco

-------
                                              Figure A-11


                                 DISTRIBUTION  OP GASOLINE  PURCHASES
  100
co

co 80
<
X
o
CE
r>
a.
2:
uj
o
IT
111
O.

Ul
   20
                                                                                **•••••••«
             -»-

             10
                                                                       •*
                             ****
._»	»-	»—___„__»_	„_—J__—•	1	-___<_	-_«	_	1

 20       30      40      BO      60       7O      BO      00      |OO

             PERCENT OF TANK CAPACITY

-------
                                           Figure A-12
                               REFUELING EMISSIONS  CONTROLLED
   100
a


o
oc

2
O
O
w
z
o
UJ


3
flC
O
UJ
oc
eo
eo
   40
   20
             10       20      3O      40      60      6O      70      00      00

             REFUELING TEST REQUIREMENT FOR  NO EMISSIONS. % of TANK CAPACITY
                                                                              —»
                                                                              100

-------
                                                                      W//7?
                               APPENDIX B

Stage II Energy Penalties and Credits
     Total energy credits of the three Stage II systems can be calculated
by subtracting energy requirements of the three systems from the energy
value of the recovery credits derived in Section II A of this paper.
     Energy penalties are calculated for each system below:
Balance
     The balance system uses no energy to displace vapors back to the LIST.
It simply uses physical laws.  In a recent paper by the San Diego Air
Pollution Control District, however, it was noted that the certified
balance system is limited to pump at 8 gallons per minute and thus the
pump would operate for a longer period of time.-  This statement was
                                          2/
supported by Trueman Miller of Red Jacket.—   The company had calculated
the energy requirements of both the balance and the aspirator assist systems.
     Their calculations showed energy to run the pumps as 1848 KWH per year
for a 100,000 gallon per month station.  An uncontrolled station of the
same size was estimated at 1275 KWH.  The difference is 573 KWH or 230 KWH for
the typical station of 40,000 gallons per month.  Total energy credit it
689 -f gallons/yr x 125,000 BTU    -   230 KWH x 3411 BTU
                            gal.                      KWH
                                   =   86.125 x 106 - 78.45 x 104
                                   =   85.34 x 106 BTU
]_/ San Diego APCD, "APCD Response to Comments Related Ninety-Five Percent
   Vapor Recovery," August 14, 1978.
2.1
-  Kleeberg, C.F. telephone conversation with Trueman Hiller, Red Jacket
   Corporation, September 6, 1978.
-  689 = 40,000/1000 x 12 x 8.85 (Ibs of hydrocarbon vapor recovered per 1000
   gallons pumped) x   1   (conversion from Ibs to gal; see Petroleum Facts and
                     6.17
   figure, 1975).

-------
Aspirator Assist
     The Red Jacket aspirator assist system uses about 10 percent of the
pumped gasoline to create vacuum in its aspirator.   This means that 10
percent more gasoline must be pumped at these stations, resulting in an
energy penalty.
     Mr. Hi Her estimated a 100,000 gallon per month station using aspirator
assist would require 1864 KWH per year.  Total energy penalty is 1864-1275 =
589 KWH/yr or 236 KWH/yr for the typical station of 40,000 gallons per
month.  Both this estimate and the balance system estimate of energy penalty
should be considered high since typical conventional station pumps are seldom
operated at capacity of 12 gallons per minute.
     Thus the energy credit for the aspirator assist is:
         732 gal/yr x 125,000 BTU   -  236 KWH x 3411 BTU
                              gal.                    KWH
                                    = 91.5 x 106  -  80.5 x 104 BTU/yr
                                    = 90.7 x 106 BTU/yr
Vacuum Assist
     According to the manufacturer, the Hasstech vacuum assist system
requires 1.4 KWH for each 1000 gallons of gasoline pumped to operate the
vacuum pump and a small spark igniter in the incinerator.  The gasoline vapor,
once ignited, is self-sustaining in its combustion.

-------
     Thus, the vacuum assist has an energy penalty of:

           480,000 gallons/yr x 1.4 KWH    =  672 KWH
                                1000 gal          BTU
     Total energy credit is:

           359 y gallons/yr x 125,000 BTU's   -
                                        gal
                               = 44.875  x 106 BTU
229.3 x 10^ BTU
             yr

  -   229.3  x 104
                               =42.58   x 10  BTU/yr

Energy Summary

     Table 1 summarizes energy credits of the three options:

                                 Table 1

              Energy Credits of State II Systems at Typical
                              Retail Stations

               i
                                              Net Energy
                                                Credit
             Recovery Credit     Penalty      lf)6 RTI,, ,
System       (1Q6 BTU's/yr)      1Q4 BTU's/yr IU  blu s/yr
           Equivalent
           Gasoline Credit per
           1000 gallons pumped
Balance 86.125
Aspirator
Assist 9.15
Vacuum
Assist 44.875
78.45 85.34

80.5 90.7

229.3 42.5
1.42

1.51

.71
4/  Credit is given for only 50% of gasoline recovered.

-------
     Taking the equivalent gasoline credit estimates from Table 1  above

and combining them with the regulatory options defined in Section  III of

this paper, the following energy savings estimates can be made for the

period 1982 - 1995.



                                 Table 2

                  Equivalent Cumulative Gasoline Saved
                          (Millions of Gallons)

                              (1982 - 1995)

     Option           Balance           Aspirator Assist       Vacuum Assist

        10                      0                     0
       II              328                    348                   164
      III                0                      0                    .0
       IV              328                    348                   164
        V             1716                   1826                   858
       VI             1887                   2006                   943
      VII             1887                   2006                   943


     The data show that the energy savings of efforts to control refueling

vapor losses range from as low as zero equivalent gallons for the  onboard

systems to as much as 2.006 billion gallons (9,350 barrels per day) for

a national Stage II program.

-------
    APPENDIX C
Stage II Costs

-------
                               3 Nozzles
ITEM.

EQUIPMENT COST
P1p1ng/Trenchi ng(i ncludes
  installation)
Nozzles
Hoses
      •
Flow Limiter
Recirculation Trap
Aspirators
Vent Pipes
Valves, Arrestors, Hoses
Blower, Burner, PV Valves
Drain Check Valves
     SUBTOTAL FOR EQUIPMENT

INSTALLATION COSTS
System Testing
Travel
Nozzles and Hoses
Dispenser Components
Vent Pipe Modifications
Secondary Unit
     SUBTOTAL  FOR INSTALLATION
     TOTAL
BALANCE
  3850
                                       5105
  Included  in  the cost  shown  for  valves,
  arrestors and  hoses.
 'included  in  cost of "Aspirators"
  EXISTING  STATION '
ASPIRATOR        VACUUM
  3850
               6045
3200
335
90
75
75
-
-
-
-
4425 • .
600
50
30
150
-
-
680
265
90
-
b
560
200
- ' -
-
4965
600
50
30
300
100
-
1080
250 .
a
_
.
-
-
585
3300
7335
600
50
30
375
-
2205
3260
                10595

-------
ITEM

EQUIPMENT COST
Piping/Trenching(includes
  installation)c
Nozzles
Hoses
      • •
Flow Limiter
Recirculation Trap
Aspirators
Vent Pipes
Valves, Arresters, Hoses
Blower, Burner, PV Valves
Drain Check Valves
     SUBTOTAL FOR EQUIPMENT

INSTALLATION COSTS
System Testing
Travel
Nozzles and Hoses
Dispenser Components
Vent Pipe Modifications
Secondary Unit
     SUBTOTAL FOR INSTALLATION
     TOTAL
                                      3 Nozzles
BALANCE
  2120
  2695
   600
    75
   675
ASPIRATOR
  2120
                 560
                 200
  3235
   600
   150
   100
   850
NEW STATION
 VACUUM
  1760
335
90
75
75
. 265
.90
-
b
250
a
-

                                 585
                                3300
  5895
   600
   180
                                2205
  2985
                                        3370
                4085
                 8880
  Included in the cost shown for valves,
  arrestors and hoses.
  Included in cost of "Aspirators"
'551 of Piping/Trenching costs of  exi stingos tat ions-.

-------
ITEM

EQUIPMENT COST
Piping/Trenching(includes
  Installation)
Nozzles
Hoses
      •
Flow Limiter
Recirculation Trap
Aspirators
Vent Pipes
Valves, Arresters, Hoses
Blower, Burner, PV Valves
Drain Check Valves
     SUBTOTAL FOR EQUIPMENT

INSTALLATION COSTS
System Testing
Travel
Nozzles and Hoses
Dispenser Components
Vent Pipe Modifications
Secondary Unit
     SUBTOTAL FOR INSTALLATION
     TOTAL
6 Nozzles
BALANCE
  4700
                                       6855
  Included  in the cost shown for valves,
  arresters and hoses.
 Included  in cost of "Aspirators"
      Existing Station
ASPIRATOR        VACUUM
  4700
               8145
3850
670
180
150
150
-
"
-
•
5850
600
50
55
300
-
-
1005
530
180
-
b
1130
200
-
*
6740 .
600
50
55
600
100
-
1405
500
a
_
-

-
990
3300
8640
600
50
55
600
-
. 2205
3510
                 12150

-------
                                     6  Nozzles                   New  Station
ITEM                                  BALANCE       ASPIRATOR        VACUUM

EQUIPMENT COST                .  .
Pi ping/TrenchIng(includes                2585          2585           ' 2120
  installation)c
Nozzles                                   670            530             500
Hoses                                      90             90
      • •'
Flow Limiter                              150              b
Recirculation Trap                        150
Aspirators                                 _           1130
Vent Pipes                                 .             i00
Valves, Arrestors, Hoses                   _              .             990
Blower, Burner, PV Valves                  _              .  '          3309
Drain Check Valves                         _              _
     SUBTOTAL FOR EQUIPMENT           	           •	
                                         3645          4435            6910
 INSTALLATION COSTS
 System Testing                            600           600             600
 Travel                                     -
 Nozzles  and Hoses                          -                              -
 Dispenser  Components                      150       .    300             300
 Vent  Pipe  Modifications                    _              _
 Secondary  Unit                             _              _             2205
      SUBTOTAL FOR  INSTALLATION
                                         ^5Q           900            3105
      TOTAL
                                         4395          5335           10015
  Included in the cost shown for valves,
  arresters and hoses.
  Included in cost of "Aspirators"
C55% of Piping/Trenching costs  of existing ^stations v 		  "

-------
ITEM

EQUIPMENT COST
Piping/Trenching(includes
  installation)
Nozzles
Hoses
      •
Flow Limiter
Recirculation Trap
Aspirators
Vent Pipes
Valves, Arresters, Hoses
Blower, Burner, PV Valves
Drain Check Valves
     SUBTOTAL FOR EQUIPMENT

INSTALLATION COSTS
System Testing
Travel
Nozzles and Hoses
Dispenser Components
Vent Pipe Modifications
Secondary Unit
     SUBTOTAL FOR INSTALLATION
     TOTAL
9 Nozzles
  BALANCE
                                                            Existing Station
ASPIRATOR
5560
1000
270
225
225
-
'
7280 ' -
600
50
80
450
-
1180
8460
5560
800
270
-
b
1690
200
8520
600
50
80
900
100
1730
10250
VACUUM
                                  4500

                                   750.
                                     a
                                  1485
                                  3300
                                 10035

                                   600
                                    50
                                    80
                                   900

                                  2205
                                   3835
                                  13870
  Included  in the cost shown for valves,
  arresters and hoses.
 ^Included  in cost of "Aspirators"

-------
ITEM

EQUIPMENT COST
Pi pi ng/Trenchi ng(i ncludes
  installation) c
Nozzles
Hoses
      •
Flow Limiter
Recirculatipn Trap
Aspirators
Vent Pipes
Valves, Arrestors, Hoses
Blower, Burner, PV Valves
Drain Check Valves
     SUBTOTAL FOR EQUIPMENT

INSTALLATION COSTS
System Testing
Travel
Nozzles and Hoses
Dispenser Components
Vent Pipe Modifications
Secondary Unit
     SUBTOTAL FOR INSTALLATION
     TOTAL
9 Nozzles
 BALANCE
   3060
   4645
    600
    225
    825
                                        5470
     New Station
ASPIRATOR        VACUUM
  3060
                 1690
                  100
 .5785
   600
   450
  1050
2475
1000
135
225
225
800
135
-
b
1170
a
-
.
                                 1485
                                 3300
8430
 600
 450
                                 2205
3255
                 6835
                 11685
  Included  in the cost shown  for valves,
  arrestors and hoses.
  Included  in cost of "Aspirators"
c55% of Piping/Trenching costs of existing stations
                                            "

-------
ITEM

EQUIPMENT COST
Piping/Trenching(includes
  Installation)
Nozzles
Hoses
      •
Flow Limiter
Recirculation Trap
Aspirators
Vent Pipes
Valves, Arresters, Hoses
Blower, Burner, PV Valves
Drain Check Valves
     SUBTOTAL FOR EQUIPMENT

INSTALLATION COSTS
System Testing
Travel
Nozzles and Hoses
Dispenser Components
Vent Pipe Modifications
Secondary Unit
     SUBTOTAL FOR INSTALLATION
     TOTAL
12 Nozzles
 BALANCE
    6200
                                        9250
  Included  in the cost shown for valves,
  arresters and hoses.
 'included  in cost of "Aspirators"
       Existing Station
ASPIRATOR        VACUUM
  6200
                12135
5020
1330
360
300
300
-
-
-
-
8490 ' -
600
50
no
600
-
-
760
1055
360
-
b
2260
200
- • .
-
10075
600
50
no
1200
100
-
2060
1000
a
-
-
-
-
1980
3300
11300
600
50
110
1200
-
2205
4165
                 15465

-------
                                       12  Nozzles
                          New  Station
ITEM
EQUIPMENT COST
Pi pi ng/Trenchi ng(i ncludes
  installation)
Nozzles
Hoses
      • •
Flow Limiter
Recirculation Trap
Aspirators
Vent Pipes
Valves, Arresters, Hoses
Blower, Burner, PV Valves
Drain Check Valves
     SUBTOTAL FOR EQUIPMENT

INSTALLATION COSTS
System Testing
Travel
Nozzles and Hoses
Dispenser Components
Vent Pipe Modifications
Secondary Unit
     SUBTOTAL FOR INSTALLATION
     TOTAL
BALANCE
ASPIRATOR
VACUUM
   3410

   1330
    180
    300
    300
   5520
    600
    300
    900
                                         6420
 a
  3410

  1055
   180
                 2260
                  100
  7005
    600
    600
    100
   1300
                 8305
  Included  in the cost shown for valves,
  arresters and  hoses.
 'included  in cost of "Aspirators"
 C55% of Piping/Trenching  costs of  exi-sting, stations.	
 2760
 1000
    a
                                 1980
                                 3300
 9040
  600
  600
                                 2205
 3405
                  12445

-------
                               3 Nozzles


                              BALANCE SYSTEM    ASPIRATOR ASSIST   VACUUM ASSIST


Nozzle                            110                 90               8Q
Replacement


Nozzle                             90                 60               30
Maintenance

Hoses                              25  .               25               25

Aspirator                                             45
Maintenance

Vacuum Assist Processing                                               330
Unit  Maintenance



                                  225  -               220           ;-.  465

-------
                              BALANCE SYSTEM    ASPIRATOR ASSIST   VACUUM ASSIST
Nozzle                            225                 180               165
Replacement



Nozzle                            180                 120                60
Maintenance

Hoses                              45                  45                45

Aspirator                                              90
Maintenance

Vacuum Assist Processing                                                330
Unit Maintenance
                                  450                 435              .600

-------
                              BALANCE SYSTEM    ASPIRATOR ASSIST   VACUUM ASSIST
Nozzle
Replacement


Nozzle
Maintenance

Hoses

Aspirator
Maintenance

Vacuum Assist Processing                                               230
Unit Maintenance
                                  680                 655               740
340
270
70

270
180
70
135
250
90
70


-------
                               12 Nozzles
                              BALANCE SYSTEM    ASPIRATOR ASSIST   VACUUM ASSIST
Nozzle                            450                 360               330
Replacement


Nozzle                            360                 240    .           120
Maintenance

Hoses                              90                  90                90

Aspirator                                             180
Maintenance

Vacuum Assist Processing                                               330
Unit Maintenance
                                  900                870               870

-------
               Additional  Stage II Cost - "Adverse Grades"
     As Exxon U.S.A.  has pointed out, there are a certain number of
service stations where the height differential  between the top of
the underground storage tanks and the farthest  island from the tanks  is
insufficient to permit laying vapor recovery return piping with the
proper slope.  (See Sept.  1 "Supplemental Comments", Attached, at page 4).
At such locations, installation of sump systems is necessary to accomplish
proper return, to the underground storage tank, of liquid accumulations
in the vapor return line.   The impact of this fact on the total costs of
a Stage II recovery program depend, of course,  on the number of stations
affected, and the average cost per affected station.  There follow
estimates of these parameters, together with an explanation of how
Stage II total cost figures should be revised in light of these estimated
values.
Stations Affected --  The best estimate at the moment appears to be about
20%.  Estimates range from a high of 34% submitted by Exxon to a low  of
2% submitted by Gulf.  The most reliable estimates were deemed to be
those  of ARCO (10-15%) and Union (15%), as these majors have already
undertaken the task of correcting the (improperly installed) piping at
their stations in San Diego and other areas of  California where systems
were installed several years ago.  The 20% figure was chosen, rather  than
the overall average (16%)  or the average of the Arco and Union estimates
because, as Exxon argues,  the extent of the phenomenon is likely to be
greater in areas outside California.  (California, whence the presently
available estimates are derived, requires that  underground storage tanks
be buried at a minimum of four feet.  A survey  of six major cities outside

-------
California indicated that all followed the National Fire Code which
requires only 3 foot burial).

                                 Costs
Balance System — Exxon's suction-type sump system costs $50 for the
sump tank and fittings, $3 (installed) per foot for connecting pipe,
and $50 for installation of the sump, connection of the pipe to the UST,
and incremental engineering costs. . Although Exxon argues an average
run of 60 feet from the low point (point at which sump is installed)
to the UST, this estimate is inflated.  Exxon's estimate assumes pipe
must be sloped @ 1/4" per running foot, whereas CARB requires only
1/8" per running foot, and purports to include the effect of situations
where the station building comes between the UST's and the farthest _
island.  Measurements (by Bill Repsher) at a large local gas station
with an island on the other side of the station building from the UST's
indicate that a forty foot run will represent an extreme case (assuming
3/8" slope per running foot).  Since it appears that the sump can be
located within 20 feet of the UST in a large number of instances, 30 feet
is deemed a good estimate of the average run.  Accordingly, the total
average cost for an Exxon-type system, usable with manifolded balance
systems, comes to $190.
     For non-manifolded balance systems, the sump must be connected
to all three vapor return pipes coming from the far island (typically,
all three products at the far island will be affected).  This will add
$50 to the cost of the system.

-------
Aspirator Assist — Because aspirator assist systems recirculate product
in the vapor return line, a larger sump tank is required, at $75 total
cost.  In addition, the flow possible with a suction system is inadequate
and a device must be attached to the submersible turbine pump to provide
the proper draw.  This device costs $65 (installed) on a Red Jacket
submersible turbine pump (STP) and $150 (installed) on other types of
STP's.  The average cost (weighted according to market share) is $100.
An aspirator sump system must use larger diameter pipe than a balance
system, the cost estimated to be $3.36 per foot (installed).
     The cost of adding sumps to an aspirator assist system at one
facility thus come to $975.  This represents 3 times the cost per
product (3 will be affected), which cost breaks down as follows:
              $ 75 - Sump Tank
              $ 50 - Installation of sump, etc. (see Exxon system)
              $100 - piping
              $100 - uphill eductor
Vacuum Assist System - Since vacuum assist systems use manifolded piping
and do not return product thru the vapor lines, an Exxon-type system can
be used.
No incremental cost will be incurred with a vacuum assist system, however.
These systems will be able to substitute the sump system for an existing
feature whereby liquid is returned by pipe from the station low point to
the LIST.  Elimination of the piping and trenching cost associated with
this item will offset the costs of the sump system.

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     To determine balance system costs, assume 60% of stations non-
manifolded and 40% manifolded.
          % of stations affected = 20%
          Balance
             60% non-manifolded cost  = $240
             40% manifolded cost      = $190
          Aspirator
             Additional cost @  20%   = $975
          Vacuum Assist
             No incremental cost

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                                                   IfH/Jf
               APPENDIX
Bases and Assumptions Underlying  Figures
Appearing in Tables 16, 17, 18, 20,  21,
23, 24, and 25 of §VII of  Decision Paper

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                    TABLES 16, 17 and 18





                      Misinstallation





Stage II -Nature of defect is improperly laid piping



resulting in lack of proper drainback of condensed vapors



and, thereby, in excessive back pressure in vapor return



system.



     GARB estimated that a minimum of 30% of the balance



systems in California were misinstalled.  CARS Staff Report



Accompanying Proposed Revisions to ARE Suggested Vapor



Recovery Rules, October 22, 1977, at p. 10.  (This number



was confirmed as a reasonable estimate by Dick Smith of San .



Diego APCD in phonecon with Bill Repsher, MSED).



     It was assumed that the major oil companies who have



been involved with Stage II in California would learn from



experience and be able to cut the number of misinstallations



in half.  (It was not believed that a lower figure could



be achieved due to difficulties in supervising the large



number of contractors involved in an en masse installation



of Stage II systems.)  It was assumed that independents and



smaller concerns would experience the same installation



problems as were experienced in California.  As 61% of



stations fly the brands of majors, 20% represents a weighted



average of expectable misinstallations for balance systems.

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                           -2-



     It was assumed that three-fourths (15%) of these



misinstallations would cause only minor vapor recovery



problems.  It was assumed that the other 5% of misinstal-



lations would cause back pressure problems serious enough



(given that newer balance system nozzles are equipped with



back pressure shut-off devices) to interfere with dispensing



of product.  It was assumed that, as a result, dealers would



disconnect vapor return hoses or remove nozzle bellows, in



order to be able to dispense product.  Accordingly, to avoid



double-counting of this phenomemon, this 5% was only listed



under the "Tampering: Nozzles, Hoses" category.



     The companies who produce the Red Jacket and Hasselman



vacuum assist systems have adopted the practice of certifying



installation contractors, with installation training a



prerequisite to certification.  Accordingly, it was assumed



that, for these two systems, the misinstallation rate could



be reduced by 50% again over the balance system rate.  As in



the case of balance systems, the majority of misinstallations



were assumed to be of the moderate effect variety, with a



small percentage assumed to be severe enough to prompt



tampering.  (These latter were likewise listed under "Tampering



Nozzles, hoses".)

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                           -3-
     The average effect of a moderate type misinstallation
on the vapor recovery potential of the balance system was
assumed to be in the range of 20%.  For aspirator and
vacuum-assist systems, the effect was assumed to be somewhat
(15% and 10%, respectively) less as these systems operate on
negative pressure and are thus less sensitive to moderate
increases in vapor return line back pressure.

     The effect on recovery efficiency of any misinstallation
sufficiently severe to prompt tampering is deemed to be
100%, as the forms of tampering needed to cope with severe
build-ups of back pressure (namely, disconnection of vapor
return hoses or removal of nozzle bellows) would result in
complete loss of vapor recovery.

Onboard - Misinstallation of the vapor recovery processing
(hoses, canisters, purging system) portion of an onboard
control system was assumed to consist of crimped and non-
connected hoses and incorrect canisters based on the
experience of MSED's Inspection/ Investigation section with
current evaporative canister systems.  The .5% misinstallation
rate estimate is also based on I+I's experience with evapor-
ative canister systems. It was assumed that 50% of the
defects would be non-connected hoses, with a 100% effect on
recovery efficiency, and 50% would be crimped hoses and
incorrect canisters with a (moderate) 20% average effect on
recovery.  50% x 100% +50% x 20% gives the 60% (weighted  -
average) effect on recovery efficency.

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                           -4-



     It was liberally assumed that addition of a fillpipe



modification to the onboard system would increase the



misinstallation rate by 100% (to 1%).  It was assumed that



the added defects would consist of improper placement of



the fillpipe sealing device or some minor damage to the



device, with an overall average effect on recovery efficiency



of 20%.  The 40% recovery decrement in Table 2 represents



the weighted average of the processing and fillpipe



portion recovery decrements—i.e., 50% x 60% + 50% x 20%.



                  IMPROPER MAINTENANCE



                      A.  Nozzles



Stage II -From October 2nd thru 5th, MSED personnel visited



106 service stations in the District of Columbia, where a



Stage II vapor recovery regulation is in effect, but where



enforcement is understood to be minimal.  Each vapor



recovery nozzle at the stations visited was examined and its



condition noted.  If the nozzle had any defect in the



faceplate or bellows (e.g., rip or tear) which would affect



recovery efficiency, the size of that defect was recorded.



     198 first-generation, Emco-Wheaton Model 3003 nozzles-



were inspected.  So far as bellows and faceplate construction



is concerned, these nozzles are similar to the nozzle



presently certified by CARB for use with balance systems,
I/   These nozzles bear the Emco-Wheaton part No. "A303".

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the exception being that the CARB-certified nozzle has a



20% greater bellows area on its unleaded version.  Of the



198 nozzles examined, 73 had defects deemed sufficiently



substantial to affect vapor recovery efficiency.  The



frequency of occurrence of this failure mode was determined



by dividing 73 by the total number of vapor recovery



nozzles which should have been in place and functioning at



the stations concerned.  This figure comes to 198 plus 20,



the number of conventional nozzles which were being used



illegally (see Nozzles:Tampering section below).  The



frequency of improper nozzle maintenance thus came to 33-%.-



Allowing for the fact that state-of-the-art balance system



unleaded nozzles have a 20% greater bellows area (and



therefore, increased potential for damage), it was



conservatively estimated that 35% of balance system nozzles



would exhibit a recovery-affecting defect in a voluntary



compliance situation.



     The defects observed in the A 3003 nozzles were of two



types—faceplate rips and bellows rips.  Four of the 73



nozzles exhibited defects so major that a 100% loss of



recovery efficiency was assumed. . In the remaining 69



defective nozzles, there were 51 instances of faceplate'



defects deemed minor enough to have only a marginal effect



(assumed to be average in the range of 10%) on vapor recovery

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                           -6-

efficiency.  In the 69 nozzles, there were also  22  instances

of bellows rips/ with an average effect on recovery
                 2 /
efficiency of 30%—' .  The weighted average effect on

recovery efficiency of the defective nozzles was thus

calculated to be:

Weighted Average         ,  .           .  .
Efficiency Reduction = 51—x x 10% + 22—' x 30% +  4 x 100% = 22%
Per Defective Nozzle   ——^—--
2/   The average bellows defect was determined to be a rip of
     1.3 inches in length.  The average reduction in system
     efficiency resulting from such a defect was determined
     by calculating the ratio of emission flow through such
     a rip to the uncontrolled emissions generated during a
     refueling.  This calculation' was made as follows:

     Efficency
     Reduction       = Er = Q
     (as a fraction)        Qo

     where Q=volumetric flow of vapor out of rip [ft3/sec]
          Qo=total uncontrolled emissions available at 6
             gal/min (.0134 ft3/sec) dispensing rate.

     (It was assumed that Q/Qo would be roughly the same at
     other dispensing rates).

     Restating,

        Er=     A xV
           .0134 ftVsec

     where A = area of rip, and

       V= velocity of emissions passing through the rip
          (ft/sec)

     The standard rip was ajudged to be of rectangular shape
     with width equal to 1/32 x L, where L is the length of
     the rip.  (The proportion of width to length is based
     on the engineering judgment that a 2 inch rip would
     have a 1/16 inch cross-section.) The velocity of flow
     out of the rip is expressed by the formula for flow
     from a sharp-edged orifice at low pressure drops,
     namely— (footnote continued on next page)

2A/  Does not sum to 69 due to fact that 4 nozzles exhibited
     both types of defect.

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                              -7-

  2/Continued from A-6
         V = c, 2Ap
                 f
       where c, =  coefficient of  discharge of a sharp-edged
       orifice

       P- density of gasoline vapor

      &P = pressure drop  across  the orifice (rip)

       Thus, restating -
            .0134 ft /sec.     U   p
                               I  ^
       L, as noted, was measured  to be  1.3 inches.

       Cd = .60   Source: Marks,  Mechanical Engineers Handbook
            (5th ed.), p. 239.

         /=  .09821b/ft3  The  vapors were assumed  to be a _
            mixture of 40%  air, and 60% propane.
            Sources of densities:  41 Fed. Reg. 48053; Marks,
            op.cit., p, 1909.

          = .1 inch of water.  This is  believed to represent a
            conservative estimate ofAP.  According to data in
            CARB Exec. Order  No.  G-70-17, certified balance
            systems operate roughly at  .3"A? at 6 gal. per
            min. flow rates.   It  is known that a rip would
            reduceAP, and  it is  believed that a reduction to
            .1 inches water for a 1.3 inch rip if anything
            overstates the  case.
       Accordingly,
Er=.0313 x (1.3" x 1 ft)^C .60 X  12 x.l" H_0 x 5.20 Ib (F)/ft2
            (12 in)2         | f        Z      d"H20)
    .0134 ftVsec.                                        -
                            11    (.0982 lb(M) X (lb(F) sec )

                                   ft 3      (32.2 lb(M)  ft)

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                           -8-



     The expectable rate of defects in aspirator and vacuum-



assist nozzles (in a voluntary compliance situation) was



determined by examining 233 OPW-7V-A nozzles at District



service stations. The bellows design of the 7V-A nozzle is



similar to that of Red Jacket and Hasselman system nozzles.



The differences are that the bellows on a Red Jacket nozzle



has a roughly 50% greater area than that of the OPW-7V-A and



the Red Jacket nozzle does not employ a faceplate; the



Hasselman nozzle, on the other hand, employs a different



type of faceplate (concave metal instead of flat rubber^



than the 7V-A nozzle.



     The number of nozzles with defective bellows was



determined to be 15.  The percentage of nozzles exhibiting



this failure mode was determined to be 6% by dividing 15



by the number of vapor recovery nozzles examined  (233)



plus the number of illegal conventional nozzles (11)



observed at the relevant stations.  Based on the 6% rate,



it was estimated that aspirator nozzles would exhibit



about a 9% defect rate (because of the larger size bellows

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                           -9-

and because of the lack of a faceplate, which probably

serves to protect the bellows somewhat from abuse), and

about 6% for the vacuum assist nozzle (the same as for the

OPW-7V-A).

     The average size bellows defect in the OPW-7VA nozzles

was determined to be a rip of 1.6 inches in length.  Because

assisted systems operate at negative pressures, it was not

believed that there would be any appreciable vapor flow

through a rip of such size in such systems.  However, it is

believed that there would be a loss of vapor scavenging"

ability for these systems at the vehicle fillneck owing-to

inflow of ambient air at the rip—' .  The effect on the

vacuum-assist system's scavenging ability was assumed to be

in the minor range and was assigned a value of 5%.  The

effect on the scavenging ability of the aspirator assist

was assumed to be greater, though still small, and was

assigned the value of 10%.
3/   The Installation Manual for the Red Jacket Aspirator
     Assist system, for example, indicates that a small
     leak at the fillneck-nozzle interface would permit
     additional air to enter the aspirator, creating vapor
     growth and thereby decreasing slightly the normally
     small interface vacuum.  Installation Manual, Red
     Jacket; Aspirator-Assist  Product, Sept. 15, 1978,
     at p. 2.  It is obvious that ambient air entering
     from a rip would cause a similar reduction of
     the interface vacuum due to the resultant vapor
     growth at the aspirator.

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                           -10-



Onboard - For the nozzle modification case (hereafter,



"nozzle case"), it is assumed that the nozzle needed for a



tight seal would be comparable to that used in a balance



system.  Accordingly, the onboard nozzle case numbers are



identical to those used for balance systems in the voluntary



compliance mode.



     For the fillpipe modification case, it was considered



whether any loss in vapor capture efficiency could be



expected at the interface of the fillpipe seal and conventional



nozzle as a result of worn and/or deformed nozzles.  MS-ED's



Fuels Section indicated, however, that substantially worn



and/or deformed nozzles are relatively rare and that, in any



event, virtually all wear and damage occurs in the outermost



3/8 "of the spout.  The materials submitted by API indicate



that the interaction between the fillpipe seal and nozzle



would occur substantially farther up the spout than that.



See, e.g., Fig 3A in ARCO portion of API Publication No.



4306, October 1978.  Accordingly, the nozzle-maintenance



failure mode was not included in the analysis of the onboard-



control modified-fillpipe case.



                     B. Hoses



Stage II - The nature of the defect is kinking and flattening



with resultant increase of back pressure in the vapor return



line.  MSED's survey found a defect rate of roughly 32% in

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                           -11-

hoses at District of Columbia service stations.  This

compares to a 29% defect rate determined by the California

Air Resources Board in a 1977 survey of stations in the Bay

Areai/.

     The hoses involved in the surveys were full-length (12

foot) hoses and, as vacuum-assist systems utilize this

length of hose, the expectable rate of hose defects with

such systems was deemed to be in the 25% range.  A reduced

rate of occurrence (10%) was assumed for balance and aspirator

systems, owing to the fact that these systems, as certified

by CARB, employ vapor return hoses only 8 feet long and_thus

less susceptible to being run over by cars—one of the

causes of hose problems.  The hose defects found by MSED

personnel ranged from minor kinks to virtually total "crushes"

(collapsed hoses).  It was conservatively estimated that the

average constriction would cause the same sort of moderate

reductions (20%, 15%, and 10% for balance, aspirator, and

vacuum-assist systems, respectively) in recovery efficiency

as would occur with back-pressure build-ups in misinstalled

systems (non-severe cases).
4/   Report: Harmon Wong-Woo to William Lewis, Subject:.
     Field Survey of Bay Area Air Pollution Control District's
     Phase II Vapor Recovery Program; March 10, 1977.

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                           -12-



                     C. Processing Unit



     The Hasselman vacuum assist system processing unit



consists of an electrically-powered blower, an electronically-



ignited incinerator, and a control apparatus consisting of



a number of solenoids and valves.  While the system is



believed generally reliable, the electronic and mechanical



parts are, obviously, subject to wear and malfunction.



Accordingly, it was assumed that there would have to be



some average downtime associated with these units.  In



lieu of hard information about the durability of the



processing units, a nominal 2% rate was chosen.  It was



assumed that 50% of the downtime would be downtime of the



blower, with resulting 100% recovery efficiency loss, and



50% would be downtime of the incinerator, with a roughly



50% loss in recovery efficiency.  The weighted average



recovery loss is thus 75%.



                     D. Aspirator Units



     These units are deemed highly reliable by Dick Smith



of the S. D. APCD and Mike Manos, of Scott Environmental



Technology.  Accordingly, a nominal 2% failure rate (a



failure being a misadjustment of the aspirator flow



sufficient to affect vapor-return-line vacuum) was assumed,



with a marginal (10%) effect on vapor recovery.

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                           -13-

                      E. Canister System

     Though the canister system portion—'of an onboard

control system will presumably be designed to be maintenance-

free, it seemed resonable to assume that at least some nominal

amount of vehicles (2%) would exhibit some loss in processing

efficiency due to deterioration of some system component

(e.g. crack in a hose, reduced working capacity of carbon

adsorption bed).  The average loss was assigned the midrange

value of 50%.

                      F. Fillpipe Seal

     In the onboard case where a tight seal is achieved

through use of a conventional nozzle and a modified fillpipe,

the fillpipe sealing apparatus will presumably be designed

to function optimally, without maintenance, for the life of

the vehicle.  It is expected, however, that actual field

performance would fall somewhat below optimum.  Potential

recovery-affecting deficiencies include wear of the seals as

a result of nozzle insertions, and deterioration of the sealing

material itself as the result, for example, of exposure to
5/   The "canister system" includes all components installed
     between the vehicle fuel tank and carburetor for the
     purpose of adsorbing and purging vapors trapped in
     the vehicle as a result of the tight seal at the
     nozzle/fillpipe interface.

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                           -14-

gasoline vapors.  Presently, the only experimental data

regarding fillpipe seal durability is that generated for API

by ARCO.  These data show excellent seal durability.  It was

desired, however, to make a more conservative projection of

seal durability than that suggested by the ARCO data.  The

assumption that on average, 10% of the in-use vehicle

fleet will experience problems with fillpipe seals with an

average 50% reduction in efficiency strikes a mid-range

course between the optimistic scenario suggested by the

ARCO data and more pessimistic scenarios which could

be imagined.

                         Tampering

           A,B. Nozzles/Nozzles,Hoses (Stage II)

Balance System -  Observations by Bill Bepsher of MSED and

a study performed for Union Oil Company by the Weitzman

Research Co. of Los Angeles tend to indicate that a

significant number of motorists find balance-system type

nozzles difficult and onerous to use—' .  MSED's survey

of stations in the District of Columbia indicates that

dealers and attendants likewise find the nozzles onerous— .
6/   See Appendix F for discussion of these observations and
     study.  The principal reason for the distaste for the
     balance-system type of nozzle appears to be the No
     Seal-No Flow feature which requires the nozzle to be
     pressed against the fillpipe with a fair amount of
     force in order to obtain product flow.

7/   See Appendix F.

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                           -15-



Stage II nozzles require several hundreds of dollars a



year (at a typical station) to maintain and refurbish.



Stage II systems which have been grossly misinstalled



will, as has been noted, render dispensing of product



difficult. (See discussion of "Misinstallation").  All



three of these factors—inconvenience of system use,



costs of system maintenance, and misinstallations—are



assumed capable of prompting a certain amount of system



tampering. This tampering would assume  the form of



dismantling nozzle bellows or disconnection of vapor re-turn



hoses, or a failure to use vapor recovery-type nozzles—_



each tampering mode having a 100% effect on vapor recovery



efficiency.



     In conducting their survey of service stations in the



District of Columbia, MSED personnel looked for certain



forms of tampering.  At the service stations which utilized



Emco-Wheaton Type 3003 (No Seal/No Flow) nozzles, there



should have been a total of 218 A-3003 nozzles in place and



functioning.  The survey showed, however, that three of the



required nozzles had no bellows whatsoever, and that, in 20



instances, a conventional nozzle had been substituted for



the required vapor recovery nozzle.  (The District currently

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                           -16-

allows the use of one conventional nozzle per product per

            8/
service mode—7. Any such "legal" conventional nozzles were

excluded from the count).

     At the stations utilizing OPW-7VA nozzles, there should

have been a total of 244 vapor recovery nozzles in place and

functioning.  The survey showed, however, that 12 nozzles

had no bellows and that 11 conventional nozzles were being

used illegally.  Combining the figures for the Emco-Wheaton

3003 and OPW-7VA stations, the overall tampering rate was

determined to be:

     Overall
     Tampering    =  23 + 23       =  10%.
     Rate           218 + 244
     (D.C. Survey)

     At the surveyed stations, a total of 63 conventional

nozzles were being legally used.  Assuming that these

conventional nozzles would have been employed regardless

of legal authority, the overall tampering rate would have

been 20%. (46 + 63).  This establishes an outer bound to
          (462+ 63)
the rate of tampering that might be expected to occur in a

voluntary compliance situation.  As a conservative projection,

a midrange figure of 15% was assumed to represent the

actual rate of tampering which would occur.
8/   Provided that there is at least one vapor recovery
     nozzle per product per service mode.   (The two
     service modes referred to are attendant-serve and
     self-serve).

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                           -17-



     As already noted under "Misinstallations", 33%  (i.e. 5%



of 15%) of this tampering would be attributable,  in  the case



of balance systems, to gross systems misinstallations.  As



likewise already noted, this 5% would be reduced,  in the



case of aspirator and vacuum-assist systems,  to 3% and 2%,



respectively.  It is assumed that the remaining 67%  of the



tampering (10% of 15%) would be divided equally among



economic and convenience motivations.  Since  the  differences



in the costs of maintaining balance systems and assist-



system nozzles are not extreme, a 5% tampering rate  attr-ibutable



to economic considerations was assigned to assisted  systems.



As the survey of nozzle use shows—' , however, assisted



systems nozzles do not appear as  onerous to  use  as  the



heavier balance system nozzles (also made more onerous by



the necessity of a no-seal no-flow feature) and thus will



not share in the 5% of tampering attributable to  the user-



convenience motivation.



                 A. Nozzles — Onboard



     Nozzle-modification—As the nozzle employed  in  this



type of system has essentially the same features  as  a



balance system nozzle, the balance system tampering  rate



(excluding misinstallation-motivated) was assumed  applicable.
£/   See Appendix F.

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                           -18-
     Fillpipe-modification—The only nozzle  tampering
applicable to this form of control would occur when an
unleaded nozzle was used to fuel a vehicle designed for
leaded fuel, and therefore containing an oversized  (compared
to the fillpipe seal on an unleaded car) fillpipe seal.
The current estimate of the rate of use of unleaded
nozzles on leaded product dispensers is 3 to 4%—' , and
the current estimate of the percentage of new cars designed
to run on leaded fuel is 5%—•' .  Accordingly,. the amount
of this form of tampering is deemed to be negligible.
     In addition, the effect on recovery efficiency of this .'
form of tampering is deemed to be minimal.  This is because
the fillpipe seals are designed substantially undersized
compared to the convential nozzles with which they are
intended to be compatible.  The API report on onboard
controls, for instance, shows  the inside diameter of
what is taken to be the seal for an unleaded vehicle to be
about .7 inches.  If the seal  for a leaded car were sized
in the same proportion to a leaded nozzle as the seals for
unleaded cars are sized in proportion to unleaded nozzles,
10/  Source: MSED Fuels Section Statistics.
ll/  Source: MSED Fuels Section estimate.

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                           -19-

their inside diameter would be about .78 inches.  Thus, even

if a designed-for-leaded-fuel vehicle were fueled with an

unleaded nozzle, the nozzle would still be larger (by

six-hundredths of an inch) than the seal.  Accordingly, a

nominal (10%) loss in recovery efficiency was attributed to

this failure mode.

                    C. Processing Unit

Stage II - This "failure mode" consists of a user's deliberately

turning off the vacuum-assist secondary unit with resultant

100% loss of vapor recovery efficiency.  As discussed

under the sub-section "Tampering: Nozzles", 15% is the

estimated rate at which balance system-type nozzles would

be tampered with in a voluntary compliance situation, for

the purpose of obviating difficulties associated with the

use of such nozzles and for economic reasons.  Overall,

the incentive for shutting off a vacuum assist secondary

unit would appear to be equally as great.  To begin with,

there is the fact that the unit consumes about $50 worth

of electricity (annually) at a typical station where such

                           127
a system would be installed—'.  More significantly,
12/  Because of the relatively high capital cost involved,
     it is assumed that vacuum assist systems will be  '
     installed only at higher throughput stations.  The
     $50 figure is EPA's estimate for a nine-dispenser,
     60,000 gal. per month station.

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                           -20-



typical annual maintenance costs of the unit are estimated



at $330 per year—.  Particularly at outlets where



maintenance costs run higher than average, this level of



expense will tend to induce cost-saving system shutdowns.



Given the economic incentives and the 15% level of pro-



jected nozzle tampering in the case of balance systems and



onboards (modified-nozzle case), it is not believed that a



15% shutdown rate is unrealistic for a voluntary compliance



scenario.



                      D. Canister System



     The rate of tampering with current evaporative canister


               147
systems is 2.6%— .  As the most typical form of tampering



consists in a disconnected hose— , as a worst-case



scenario it was assumed that the average effect on recovery



efficiency for this failure mode is 100%.



                     E. Fillpipe Seal



     The MSED Draft Tampering Survey shows a 3.4% rate of



fillneck tampering.  It is assumed that the addition of a



seal to the fillneck will neither deter nor increase this



tampering.  The effect on vapor recovery efficiency is



assumed to be total—i.e., 100%.
13/  This is the estimate used in EPA's cost-effectiveness

     study.



14/  Source:  MSED Draft Tampering Survey.



15/  Source:  MSED Technical Support Branch.

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                           -21-

                      Table 20

     In order to determine the actual efficiency of the

Stage II programs, it was necessary to assume the proportion

of regulated throughput which would be covered by each

type of Stage II system.  It was assumed that the cheapest,

although most difficult to use system-i.e., the balance

system-would be installed at all non-retail outlets and, in

addition, would be used on all attendant-serve retail

throughput.  These assumptions result in balance systems

covering 55% of regulated throughput—' . The remaining -.-

45% was split between the assisted systems on a 35%,

10% basis on the assumption that the aspirator assist

system would capture the lion's share of the self-serve

retail market, with the relatively expensive vacuum assist

system being installed only at very high-throughput stations.
16/  The 55% figure is based on the outlet coverage
     pattern of Option V.  According to the November, 1976
     Arthur Little Report, non-retail stations with greater
     than 10,000 gallons per month throughput pump 53% of
     the non-retail throughput which throughput, according
     to the July, 1978 Arthur Little Economic Impact Study,
     is 23% of the national total.  Accordingly, greater-than-
     10,000-gallons-per-month non-retail outlets pump 12% of
     national throughput.

     According to the May 5, 1978 Lundberg Letter, 46% of
     service-station throughput is currently attendant-served,
     Thus, given Arthur Little's 1978 estimate that retail
     throughput is 77% of the national total, attendant-
     serve retail throughput constitutes 35.4% of the
     national total.  Accordingly, the percentage of
     regulated throughput covered by balance systems
     would be 55%. (12% + 35.4%) = (47.4%)
                   ( 77% + 12% )  (89%  ) .

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                           -22-

                         Table 21

     The estimates of total non-compliance were obtained

by using existing rates of non-compliance with Stage I vapor

recovery regulations as a baseline.  Region II estimates a

current total non-compliance rate at service stations of

12%, despite the fact that the Region has been active

in enforcing Stage I, and despite the fact that the regulations

have been in effect for 2 1/2 years.  Stationary Source

Enforcement indicates that the rate of total non-compliance

with Stage I regulations at small bulk plants is quite

large—probably well in excess of 40%.  With'these two

guideposts, the 40%f 30%, 20% estimates of total non-

compliance appear conservative, if anything:

     1.   Stage II regulations are substantially more
          onerous, both economically and as a burden
          on service station operations, than Stage I
          regulations.  (Stage I costs only about $900 per
          station and requires little, if any, operating
          and maintenance costs; Stage II costs $7,000 at
          a typical station for the cheapest system, and
          costs several hundred dollars a year to maintain).

          The economic impact of Stage II at a service
          station is perhaps more comparable to the economic
          impact of Stage I at bulk plants (10 to 11 thousand
          dollar investment) and, accordingly, the rates of
          Stage II non-compliance should be akin to those
          for Stage I at bulk plants.

     2.   The Stage I compliance figures reflect a situation
          where at least 1 in 10 stations per year are
          being checked for compliance, whereas Table 21
          assumes a  voluntary compliance scenario.

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                           -23-

     3.   There are not known to presently be any equipment-
          availability problems associated with Stage I
          implementation.  It must be assumed that there
          will be some delays due to equipment shortages
          if Stage II is implemented on a large scale—
          particularly, if implemented on a nationwide
          basis—7.

                          TABLE 25

     As was indicated on page 8 of §VII, the optimum form

of any Stage II regulation would be an emission limitation

standard, supplemented by minimum equipment and maintenance

standards, and the optimum strategy for enforcing such a

regulation would consist primarily of visual inspections

of vapor recovery equipment at service stations.  (See

Appendix E for rationale.)  As was also indicated on  page-

8, the optimum form of an onboard control (modified-nozzle)

regulation would be a dual performance standard, with the

optimum strategy for enforcement consisting of monitoring

compliance with the standard for the onboard portion of the

apparatus through the certification and in-use testing

programs, and monitoring of compliance with the standard for

the nozzle portion of the apparatus through in-use pressure

testing of nozzle sealing ability.  (See Appendix E). Table

25 sets out, for the various program options, the rates at
17/  In 1976, for example, Arthur Little estimated that'18
     to 24 months lead time would be needed to produce the
     requisite number of nozzles if Stage II were required
     in only 11 AQCR's.  Arthur D. Little, Inc., Economic
     Impact of Stage II Vapor Recovery Regulations, November,
     1976, at 204.

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                           -24-

which gasoline-dispensing outlets could be inspected, using

40 man-years' resources in the optimum enforcement strategy,

with the regulation written in its optimum form.  These

rates of inspections were determined from the total inspections

figures calculated in Appendix E as follows:

1.  Stage II-Nationwide (Option V) —

    Rate of    =    Number of Inspections
  Inspection     Number of Regulated Outlets

              = 19,750   = 1 in 9
               176,000


Onboard - Modified Nozzle Case

    Rate of  =    Number of Inspections	
 Inspection   Number of Regulated Outlets

            =  26,000,n=7 1 in 7
              176,000—'

2.  Stage II - Nonattainment Areas —

    See Discussion of Table 23 following.
18/  Assumes enforcement efforts respecting non-retail
     outlets would concentrate on those with 10,000 gallons
     per month and greater throughput.  Other non-retail
     outlets account for only a small fraction of national
     throughput.  Arthur D. Little 1976 Report.

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                           -25-

                         TABLE 23


            A.  Nonattainment Area Program


     Tables 23 and 24 set forth the assessed effects on

non-compliance rates of the inspections performable under

the optimum enforcement strategy.  Basically, the non-

attainment area columns in Table 23 show 50% reductions

over the non-compliance rates appearing in Table 18.  This

50% rate of reduction was arrived at by the following

reasoning:

     1.   §113(a)(1), under which a non-attainment area

program would be enforced, requires, after the initial

determination of violation, a 30-day grace period and

redetermination of violation before any legal action can

be taken.  It was optimistically assumed that, at a minimum,

any station initially determined to be in violation which

could be re inspected would be brought into compliance.

     2.   The percentage of violators which would initially

be determined to be in violation and which could be

reinspected was determined to be 40% by the following

reasoning:

2 x #of Stations Inspected + 1 x #of Stations Inspected
         Twice                            Once =

                      Total Inspections Performable

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                           -26-

     This formula can be expressed as:

2 x Total ftof Stations Inspected x % of Stations +
        Total # of Stations          Reinspected

Total IStations Inspected x (100%-% of Stations   =
   Total # of Stations             Reinspected)

Total Inspections Performable
     Total t of Stations

The total number of Stage II inspections performable with 40

man-years' resources (see Appendix F) is 19,750.  The total

number of stations covered in a non-attainment area program

is 34,175.  The percentage of stations reinspected

                   197
is estimated at 50%—. Accordingly,

2 x Total tStns. Inspected x 50% + Total ftStns. Inspected .
     Total # of Stns.                 Total # Stations

x 50% = 12,750  = 	1_
        34,175    1.73

And, therefore,

Total #Stns Inspected X (2x50% + 50%) =  1
  Total f Stns.                        1.73
19/  This is the weighted average, by throughput, of the
     reinspection rates for balance, aspirator and vacuum-
     assist systems.  The individual rates are 67%, 30%
     and 50%, respectively, based on the proportion of
     overlap deemed to exist among the failure modes set
     out in Table 16 and the degrees of frequency of the
     failure modes set out in Table 18.

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                           -27-

Thus,

Total ftStns. Inspected =  1    x  1
  Total * Stns.       -.  1.73    150%

                             =  i  IP/
                               T76~  =  40%

     This figure represents the proportion of stations

which will be visited at least once if 50% of the stations

are being reinspected.  This figure accordingly represents

the percentage of violators who will be caught and rein-

spected.

     3.   It was assumed that, in addition to the 40%

reduction in non-compliance attributable to inspection and

reinspection of outlets, there would be a modest (estimated

at 10%) spillover impact on non-compliance produced by the

relatively high (1 in 2.6) overall frequency of inspection,

even though §113(a)(l)'s preclusion of taking legal action

based on an initial determination of violation strictly

speaking militates against creating any deterrent effect.


                  B.  Nationwide Stage II


     The non-compliance rates shown in in the Nationwide

Stage II columns of Table 23 generally show 33% reductions
20/  This ratio of the stations initially inspected to total
     stations constitutes the overall inspection frequency
     for non-attainment area programs appearing in Table 10.

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                           -28-

over the rates appearing in Table 18.  One-third of this

reduction is attributable to forced compliance at inspected

        217
stations—' . The other two-thirds is the estimated result

                                                   22/
of the deterrent effect achievable under §113(a)(3)—'

with a 1 in 9 inspection rate.


           C.  Onboard-Control/Modified Nozzle


     The nozzle tampering and nozzle maintenance non-

compliance rates for the onboard-control, modified-nozzle

option show approximately 40% reductions over the rates.

appearing in Table 18.  About one-third of the 40% reduction

is attributable to forced compliance at inspected outlets—

the inspection rate in the onboard case being 1 outlet  in
 237
1—'.  The remaining two-thirds, as in the case of
2I/  The percentage of violators brought into compliance as
     a result of being caught in an inspection is expressed
     by  the rate of inspection—in this case, 1 of 9, or
     11%.

22/  §113(a)(3), which governs enforcement of NESHAPS
     (§112) regulations, permits legal action to be taken
     upon the initial determination of violation.

23/  The percentage of reductions in non-compliance
     attributable to forced compliance is expressed as in
     the case of Nationwide Stage II, by the rate of
     inspection—in this case, 1 in 7, 14%.

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                           -29-



Nationwide Stage II, is attributable to the estimated



deterrent effect achievable under §113(a)(3), with the 1



outlet in 7 inspection rate.



     Categories of failure modes for which the reduction



in non-compliance rate was estimated to be other than 50%



(for a non-attainment area Stage II program), 33% (for a



nationwide Stage II program), and 40% (nationwide onboard,



modified-nozzle case) include: Aspirator unit (improper



maintenance), Vacuum-Assist Processing Unit (Imp. Maint),



Canister system (imp. maint.),  Canister system  (tampering)



and Misinstallation (onboard/modified-nozzle).  These noji-



compliance rates were not changed as the system defects



involved would not be subject to detection and/or cure using



the enforcement strategies selected as optimum.



                        TABLE 24



     The rates of total non-compliance set out in Table



24 show year-by-year incremental reductions over the rates



set out in Table 21—down to a believed maximum  level of



installation (95%).  The rate by which non-compliance is



reduced each year is 50% for the non-attainment  area



program and 33% for the nationwide program—the  rates



deemed generally applicable to reductions in non-compliance



for other failure modes. See preceeding discussion of Table



23 figures.

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                  APPENDIX E








   Selection of Optimum Enforcement Strategy for Each



Program Option; Calculation of the Numbers of Enforcement



Inspections Achievable Thereby for Each Program Opt'i'on;  .



Costs of Administering Optimum Enforcement Strategy -for



Each Program Option; Administrative Considerations



Respecting Various Enforcement Options

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I.  OPTIMUM ENFORCEMENT STRATEGY FOR EACH PROGRAM OPTION





     In order to assess the impact on compliance rates of



the commitment of 40 man-years of resources to enforcement



of Stage II and onboard (modified nozzle) programs, it is



necessary to determine how those resources would be used.



In order to make this determination, it is in turn



necessary to assess the optimum strategy for enforcement



of the various programs. The success of any enforcement



strategy can be measured by the percentage of non-complying



outlets brought into compliance in a given year.  The



percentage of non-compliance "cured", in turn, depends on



two factors: the percentage of violators who are "caught"



and legally forced into compliance, and the percentage of



violators who, though not caught themselves, are deterred



into compliance as a result of seeing other violators caught



and dealt with under the law.  Both of these factors obviously



thus depend on the percentage of violators who get caught in



a given year which, in turn, depends upon the number of



regulated outlets which can be tested for compliance within



that year.



                 A.  Stage II Programs



     So far as Stage II is concerned, the compliance test



relied upon at the time of the Nov. 1, 1976 proposal

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                         -2-



was the Short Test then under development by the Office of



Enforcement.  The  short test was designed to measure the



mass emission rate (grams per gallon dispensed) of Stage



II systems, and it was proposed to couch EPA's Stage II



standard as a mass emission limitation measurable by the



Short Test.  The enforcement strategy deemed optimum



consisted of field testing regulated outlets using



that test.



     While developmental work on the Short Test is not yet



quite completed, much is known about the manpower and time



requirements associated with this test (and with the Refueling



Emissions Simulation Test [REST] enforcement procedure, also



currently under development). That which is known, when



considered in conjunction with statutory limitations on the



treatment of violators, indicates there is little prospect



of forcing or deterring meaningful percentages of violators



into compliance with either the nationwide or nonattainment



area Stage II programs currently being considered by EPA—



if either the Short Test (or REST) constituted the exclusive



compliance test mechanism.



     The percentage of outlets which can be compliance-tested



in a given year is the ratio of the number of outlets which



can be compliance-tested in that year to the total number



of outlets.  To determine this ratio for the nationwide and



nonattainment area Stage II programs being considered by

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                          -3-


EPA, assuming 40 man-years' resources were devoted to

enforcement, the starting point is the number of compliance

tests which can be performed with 40 man-years' resources

for each type of enforcement mechanism.

     The Short Test measures vapor recovery system emissions

occurring during actual vehicle refuelings.  Vapors emitted

at  the nozzle-fillpipe interface are captured by a

flexible sleeve and fed into recording instrumentation.

     According to MSED and NEIC personnel, the Short Test

requires two people—one to conduct the vehicle refueling

process and one to handle the instrumentation.  As presently-

conceived, the test requires that emissions from 100 cars

be measured in order to establish a violation.  Experience

to date with use of the short test indicates that about 75

cars can be measured at high throughput stations in an

average eight hour workday— .  An average regional

S&A inspector spends about 50% of his time in the
I/   Source: Interim Report on the Stage II Vapor Recovery
     Short Test, December 30, 1976, Table I; March, 1977
     Updated Report, Addition to Table I; Records of Bill
     Rutledge, who was involved in the testing.

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                              -4-

field—' .  Thus, even under the most optimistic of

assumptions, the number of complete short tests which

could be performed by a team of two inspectors in a year

would be roughtly 100— , or 50 per man-year.
2/   A fifty-fifty field-to-office time split was estimated
     by both Jules Cohen (NEIC) and Keith Silva  (a former -
     fuels inspector now working in MSED).  In addition,
     a fifty-fifty split is consistent with information
     supplied by Mark Siegler about the unleaded inspection
     program.  Mark indicates that roughly one hour was
     alloted per inspection and that inspectors  averaged
     about 1,000 inspections per year.  At eight inspections
     per day, 1,000 inspections would require about 125"
     days in the field.

_3/   130 days x 3/4 test/day = 98.  There is no  reason  to
     assume the figure will be any higher.  Indeed, as
     noted, the 75 car per day figure was achieved at
     relatively high throughput stations.  At lower
     throughput stations, attainment of even the 75 car
     per day figure will be impossible.  For example,
     assuming 25 days' a month operating time, a 15,000
     gallon per month facility will dispense about 600
     gallons of gas in an average day.  As automobile
     owners (on average) take about 10.5 gallons per trip
     to the station, a 15,000 gallon-per-month facility
     services only about 57 cars a day.  Thus, even if  all
     cars were utilized, a short test at this size facility
     would consume the better part of two days.  (In
     practice, of course, cars tend to arrive at the
     station in "bunches"—particularly during the morning
     and evening peak periods—and not nearly all the cars
     can be utilized).
          No increases in the ratio of field time to office
     time appear likely, as data reduction for the short
     test takes about two hours. Lastly, it may  be necessary
     to obtain warrants to inspect for vapor recovery
     violations as a dealer who realized his station was in
     violation could gain valuable time for performing
     needed maintenance by turning a warrantless inspector
     away.

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                              -5-


     Based on past experience, 40 man-years of federal

enforcement resources would be allocated as follows:

     50% - field inspectors
     25% - legal support
     25% - administrative, clerical support

The annual number of compliance tests performable with the

Short Test using 40 man-years' resources can thus be

expressed as:

     Short Tests  =  20 man-years x 50 tests   =1000
     Performable                    man-year


     EPA estimtes that the total number of outlets covered

by Option V (Stage II nationwide, with exemptions) would" be

176,000 and that the total number of outlets covered under

Option II (Stage II, nonattainment areas) would be 34,175.

The percentage of outlets which could be compliance-tested

in a given year under these programs, using 40 man-years

resources and the Short Test, would thus be 1 in 176 and 1
     4/
in 50—' , respectively.  The percentage of violators who

can be forced into compliance with such inspection rates are

roughly half-of-one percent and three percent respectively.

It is not believed that such rates of detection of violators
4/   The percentage of total outlets inspectable in a given
     year in a non-attainment area program, where (see p, 8
     below) violators must be inspected twice, was calculated
     using the method set out in Appendix D, at pp. 25-27.

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                              -6-



would deter any substantial numbers of violators into



compliance.



     The alternative compliance test to the Short Test,



known as the REST procedure, would not measure emissions



during actual vehicle refuelings.  Rather, emissions would



be determined by measuring the vapors escaping when gasoline



was dispensed into two portable fuel tanks equipped with a



number of interchangeable fillnecks designed to be represent-



ative of the on-the-road vehicle population.  As in the case



of the Short Test, two persons are required to perform the



procedure.  By eliminating the need for actual vehicle



refuelings, however, the REST procedure achieves a time



advantage over the Short Test.  Mike Manos, the lead engineer



for the REST project contractor, estimates that about three



hours will be required to perform the test at each station.



In addition, a daily calibration of the equipment requiring



about 45 minutes will be necessary.  Adding in travel time



to and from stations, the most reasonable estimate at this



point is that, using REST, two service stations could be



tested per day by each team of two inspectors.  This means



that one team could inspect about 260 stations per year.



(130 field inspection days x 2 tests per day).  Accordingly,



130 tests can be performed per man-year.

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                           -7-


     Using the percentage allocation of enforcement resources

assumed above, the number of REST test procedures performable

in a year with a 40 man-year resource effort comes to 2600.

(20 man-years x 130 tests per man-year).  Accordingly, the

percentage of outlets which could be compliance-tested in a

nationwide Stage II program, using 40 man-years of resources

and the REST procedure, would be 1 in 67.  Like the inspection

rates for the Short Test, this rate is deemed inadequate to

bring about any significant amounts of forced or deterred

compliance.

     For a nonattainment area program, the percentage of" -

outlets which could be inspected in a given year using the

REST procedure would be 1 in 20— .  This inspection rate

produces only 5% forced compliance.  Moreover, given the

statutory procedural limitations on enforcement of a non-

attainment area program, an inspection rate of this magnitude

will produce virtually no deterrence.  The problem is that

nonattainment area regulations would have to be promulgated

under authority of §110 of the Act—i.e., as remedies for
5/   The percentage of total outlets inspectable in a given
     year in a non-attainment area program, where (see p. 8
     below)  violators must be inspected twice, is calculated
     using the method set out in Appendix D, at pp. 25-27.

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                              -8-

deficiencies in state implementation plans.  Under the scheme

of the Act, §113(a)(l) would govern enforcement of such

regulations.  §113(a)(l) requires, before any enforcement

proceeding can be initiated against a violator-

     1.   determination of a violation

     2.   submission to the violator of a notice of such
          violation

     3.   a 30 day waiting period (during which such
          violation may be remedied)

     4.   redetermination of the violation subsequent
          to the conclusion of the 30 day period

     These procedural requirements pose an almost insuperable

barrier to creation of an effective enforcment deterrent" in the

context of a non-attainment area Stage II program—at least

where enforcement depends on a test procedure which can be used

on a regulated outlet only once every twenty years on average.

Under §113(a)(1), the violator has every incentive to wait to

be caught before performing needed system maintenance.  He can

avoid civil penalties merely by performing the maintenance

during the grace period.  Meanwhile, during the 19 years (on

average) between enforcement inspections, the violator can save

substantial amounts of money by neglecting system maintenance.

     The inability of the Short Test and REST procedures to

produce substantial amounts of forced or deterred compliance at

outlets subject to either national or non-attainment area Stage II

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                          -9-



regulations—even with the application of 40 man-years of



resources—serves notice that the in-use emissions testing



enforcement strategy envisioned in the November 1, 1976



Stage II regulatory proposal needs to be altered.  The



problem, in summary, is that the time needed to perform any



emissions test, coupled with limitations on enforcement



resources, will prevent enforcement efforts from achieving



substantial amounts of forced or deterred compliance.



     It should be noted, however, that many of the failure



modes which will occur with Stage II systems (e.g. nozzle



rips and tears, hose defects, nozzle or hose tampering,



shutting off of vacuum assist systems) are matters readily-



visible to the eye.  This suggests that more non-compliance



could be cured if a Stage II emission standard could be



supplemented by a standard specifying minimum maintenance



and  operational requirements for the various types of vapor



recovery systems.



     There appears to be legal authority for imposing such a



standard.  In the case of a nationwide Stage II program,



§112(e)(l) provides that:



     11 [I] f, in the judgement of the Administrator, it is not



     feasible to prescribe or enforce an emission standard



     for control of a hazardous air pollutant... he may



     instead promulgate a design, equipment, work practice



     or operational standard, or combination thereof whicl)



     in his judgment is adequate to protect the public

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                         -10-

     health from such pollutant... with an ample margin of

     safety.  In the event the the Administrator promulgates

     a design or equipment standard... he shall include as

     part of such standard such requirements as will assure

     the proper operation and maintenance of any such element

     of design or equipment."

According to §112(e)(2), the phrase "not feasible to prescribe

or enforce an emission standard" covers an enforcement

situation of the Stage II type as it includes "any situation

in which the Administrator determines that... the application

of measurement methodology to a particular class of sources ••

is not practicable due to technological or ecomonic limitations."

     In the case of a nonattainment area program, §110(a)(2)

(b) specifies that State Implementation Plans contain

"emission limitations... and such other measures as may be

necessary to insure attainment and maintenance of [air

quality standards.]..."  The emphasized languange is believed

broad enough to cover equipment/maintenance standards made

necessary by technological and economic limitations associated

with currently available emissions testing procedures.—
6/There is precedent for EPA's setting equipment standards in
the SIP context.  See, e.g., Stage I regulations requiring
submerged fill pipes and no-connect no-flow features in
addition .to setting a performance standard.  See 40 C.F.R.
§52.1598 for sample Stage I regulation.

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                         -li-

     lt is estimated that as many as ten stations a day

could be visually inspected for compliance with an equipment

(with minimum maintenance requirements) and operational

 tand  d —/ Eac^ inspection would require only one inspector.

The Short Test and REST, by contrast, both require two men

to perform and the numbers of each test which can be performed

in a day are three-quarters and two, respectively.  Accordingly,

substantial advantages in enforcing Stage II programs would

be achieved if the emissions limitation standard were

supplemented (on the rationale of enforcement necessity) by

an equipment (with required maintenance) and operational

standard enforceable by visual inspections.8/
—' See discussion below.

8/
—The emissions limitation standard and emissions testing
could not be eliminated entirely.  Misinstallations which
are not so severe as to result in gross system tampering
would not be subject to visual detection; accordingly, the
threat of emissions tests must be preserved  in order to
promote proper system installations.  In addition, some
amount of emissions testing will be necessary to deter the
installation of system types which, even though properly
maintained and otherwise in conformity with  a general
equipment/maintenance and operational standard, do not
achieve sufficient emissions reductions.  Testing results
would also provide, in the early years of any Stage II
program, information upon which dealers could make purchase
decisions regarding systems and, in later program years,
information upon which updating or revision  of equipment/
maintenance and operational regs could be based.
     It is believed that about 250 emissions tests a year
would be adequate for these purposes.  This  means that,about
25% of field inspection time would need to be allocated to
emissions testing.  (This assumes use of the Short Test.

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                            -12-
Footnote Continued
The number of emissions tests performable can be expressed
as:

tTests     =     % of Inspector   x   Total # of  x  # of
Performable      Time Allocated       Man-Days per   Inspector
In one year      to Emissions         Inspector      Man-Years
                 Tests                Man-Year

                          x Test Performable
                            Per Inspector
                            Man-Day

Thus, the % of Inspector Time allocated to emissions testing

can be expressed as:

% Inspector
Time Allocated =  250 tests  x  	1	
to Emissions           year     130 Man-Days x 20 Man-Years
   Tests                        Per Man-Year
                   x   3/8 Test Per
                           Man -Day

                   =25%  ).

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                         -13-



                 B.  Onboard Programs



Modified Fillpipe .Case — This program option, could be

                                              9 /
enforced, at probably modest incremental cost,—'  by


including the onboard vapor recovery function among those


monitored within the established certification and in-use


testing programs.  The standard would be a performance


standard couched in the form most compatible with measure-


ment techniques employable in conjunction with the Federal


Test Procedure evaporative emissions tests.


Modified Nozzle Case — This program option would add a


tight-sealing nozzle function to the enforcement workload


for an onboard control program.  Fortunately, there appears


to be a mechanism available for effectively dealing with this


problem.  At a July, 1976 briefing of EPA officials, API's


task force on onboard controls demonstrated a pressure test


of nozzle sealing ability.  This procedure was simple,


involving just the insertion of the nozzle  into a standard-


ized fillpipe capable of being pressurized by means of an


electric pump.  Under this procedure the flow of air out of


a leak  (if any) is read from a flowmeter inserted into the


pressurized system.  Nozzle sealing ability can then be


determined from the pressure gauge and flowmeter readings.
9/See subsection III below.

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                         -14-

     This test can be performed very quickly, and the

equipment needed for it is inexpensive.—' This suggests

that, in the case of an onboard-control/modified-nozzle

program, the performance standard for the onboard portion of

the apparatus be supplemented by a performance standard for

nozzle sealing ability, enforced by use of the described

nozzle pressure-testing procedure.

II.  Numbers of Inspections of Fuel-Dispensing Outlets

     Performable With 40 Man-Years' Resources;

     Stage II and Onboard-Control/Modified-Nozzle Options

A.  Stage II (Enforcement Mechanism; Visual Inspections"plus

Short Test)-                                            -  .

     As previously noted, it is anticipated that 75% of

field inspection time would be allocated to visual inspection

of service station vapor recovery equipment; 25% to systems

emission testing.  As likewise already noted, a field

inspector typically spends about 50% of his time, or 130

man-days in the field.  As noted, three-fourths of a short

test can be completed in one day by two people; accordingly,

the rate of emission testing with the Short Test, per man

day, equals 3/8.  It is estimated that visual inspections of

a service station will consume roughly half an hour so

that, adding in fifteen minutes travel time between stations,

about 10 stations can be inspected in a typical eight hour
_10/The entire apparatus—-standarized fillpipe, electric pump,
pressure gauge and flowmeter—is believed to cost $300 at'
most.  MSED Stage II Vapor Recovery Project estimate.

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                         -15-

workday.  Accordingly, the total number of visual inspections

and emissions tests performable with 40 man-years' resources

can be expressed as follows:

Total
Inspections/ =    75%        x  130 man-days  x 20 inspectors
Tests Performable (Inspection    per inspector      man-years  x
                  Alloction)    man-year

                  10 inspections per +  25%     x    130 man-days
                  inspector man-        (Test        per inspector
                  day                   Allocation)  man-year
                  20 inspector
                  man-years
             x  3/8 test per
                inspector man-day
               =  19,500 + 250 = 19,750

B.  Onboard (Modified-Nozzle Case)—

     Under this option, 100% of field inspector time would

be allocated to nozzle pressure-testing.  It is estimated

that pressure-testing of the nozzles at a station would

require roughly half an hour on average and thus,

factoring in travel time, 10 stations could be inspected in

an average 8-hour workday.  These inspections would require

only one man to perform and, accordingly, the total number

of inspections which could be performed with 20 man-years'

resources allocated to field inspections can be expressed as

follows:
Total
Pressure Tests
Performable
130 man-days   x  10 tests
per inspector     per inspector  x
                    man-year

                    20 inspector
                       man-years

                 =  26,000
                  man-day

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                         -16-

III.  Costs of Implementing Optimum Enforcement Strategies


Stage II -  40 Man-Years' Resources

     As noted, 40 man-years of resources would be allocated

to the enforcement -of Stage II programs as follows:  50% for

field inspection, 25% for legal support, and 25% for adminis-

trative/clerical support.  Past experience indicates that the

cost per man-year of such an allocation, when travel costs

are included, comes to about $30,000.  To this must be added

the cost of test equipment figured as follows (Short Test

assumed the operative test) :
     Cost of Test Apparatus Per Unit - $1 ,QQQ=j
     Cost of Transport Van           - $10,000—


Annualized   =  (7,000 + $10,000) x .263—' x 10 teams
Cost of Test
Equipment

                   = $40,000 per year

Accordingly, the annual costs of enforcing either Stage II

option with 40 man-years' resources comes  to $1,240,000.

(40 man-years x $30,000 per man-year + 40,000).
_ll/Sources:  Jules Cohen (NEIC), Mike Manos  (Scott Environmental
Technology).

12/Includes $2,500 to modify the van.  At least a 3/4 ton van
Ts required.

].3_/Capital Recovery Factor for assumed 5 year useful life.

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                         -17-
Onboard

   Modified Fillpipe Case

     As already noted, the onboard-control, modified-fillpipe

option can be enforced through the established certification

and in-use testing programs.  It appears that the amount of

personnel and equipment needed to effectively enforce this

type of onboard control would be much less than that required

for enforcing service station controls.  Marty Reinemann, of

MSAPC, has indicated that testing the onboard control system

would add only about 1/2 man-year to the MSAPC certification

       14/                                                  • i
program—, and would require only about $50,000 in

equipment costs.—  According to Mort Cohen—' and Roy

Reichlen,— monitoring onboard controls would probably not

require any additional personnel in the Recall or Technology

and Testing Sections of MSED.  Additionally, according to

Roy, the increase in the testing budget necessary to accommo-
14/This estimate is based on the assumption  that only several
hundred tests of onboard-equipped vehicles  (about one-half the
number of tests currently used for certifying the evaporative
emissions control system) will be necessary  to certify-onboard
vehicles.

1^5/This would be the cost to equip 2 or 3 SHED's with the
capacity for measuring the onboard vapor control function.

l_6/Acting Chief, Recall Section.

_17_/Chief (at time of communication), Technology and Testing
Section.

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                          -18-

date the monitoring of onboard controls would be modest,

running at most 10% of the FY 79 budget of $1.5 million.

Accordingly, the annualized cost of enforcing this type of
                                                 18/
onboard control program would be about $178, 500.—'


Modified Nozzle Case - -

      The costs of enforcing this option would consist of

the cost of enforcing the performance standard for the

onboard portion of the apparatus and the cost of enforcing

the performace standard for the special nozzles.   The

former cost is the same as the cost of enforcing the modified

fillpipe option.   The latter cost, assuming a 40 man years

years' resource effort, would be the same as enforcing the Stage ]

options, with the exception that the annualized cost of the

equipment needed to pressure-test the special nozzles would be
IJj/Total annual cost =

        10% of $1.5 Million — $150,000
         1/2 Man year —         15,000
        Equipment costs —     $50,000 x .263  (C.R.F. for
                                5 yr.useful life)

       = $150,000 + $15,000 +  $13,500

       = $178,500

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                         -19-

  i    u    eimn 19/ Accordingly, the total annualized cost
only about $1600.—

of enforcing the modified-nozzle option amounts to:


Total Annualized = $178,500 + $1,200,000 + $1200 = 1,379,700.
Cost

     It should be noted that the foregoing costs represent

federal enforcement outlays only.  As noted in footnote

13 of Section VII, it was assumed for purposes of the analysis

therein that the enforement resources deployed were federal

enforcement resources operating under federal enforcement

authority.

            IV.  Administrative Considerations

     From an administrative viewpoint, the onboard-control

modified-fillpipe option presents the least expense and

the least difficulty.  With this form of control, enforcement

could be accomplished through a centralized mechanism using,

for the most part, existing personnel and a relatively

limited amount of testing.  (Vehicles would be tested as

classes, not on an individual basis, with the maximum number

of tests needed for any one class being the number deemed

statistically sufficient to justify a recall action.)
lj)/The unit cost of each test apparatus—consisting of
fillpipe, electric pump, pressure gauge and flowmeter—would
probably be $300 at most.  Assuming a 5-year useful life,
the total annualized cost of 20 sets of apparatus would be
$1600.   (20 sets x $300 per set x .263 Capital Recovery
Factor).

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                           -20-



     With service station controls or with onboard controls,



modified-nozzles, enforcment would be decentralized throughout



the regional offices; the upkeep of the equipment installed



at service stations would have to be monitored and compliance



would be on an individual, case-by-case basis.  Substantial



additions to and training of, inspection personnel would



thus be required, as well as a substantial amount of coordin-



ation and review of inspection personnel efforts.

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              Public Use of Nozzles


     On July 15, 1978, Bill Repsher of MSED visited  three

service stations in the San Diego, Cal. area—one station

where each type of vapor recovery system was  in use—and

observed use of the nozzles by self-serve customers.  The

results were as follows:

        - At the station with aspirator-assisted controls,
     of thirteen customers observed, twelve—' used the
     nozzle correctly without assistance - i.e. inserted
     the nozzle spout sufficiently far that the bellows
     made contact with the fillpipe or surrounding sheet
     metal.  One customer at an unleaded pump started out
     using the nozzle incorrectly - it was not inserted
     far enough to open the "trap door" in the restrictor
     area.  The customer recognized immediately that some-
     thing was wrong, however, as gas poured  back out of-
     the fillpipe, and looked around for help.  Upon being
     instructed as to what the proper technique was, she,
     proceeded to use the nozzle correctly.

        - At the Hasselman system station, each of the 11
     customers—' observed used the nozzle correctly  -
     i.e. inserted the nozzle far enough into the fillpipe
     to cause the bellows to come into close  proximity
     to the fillpipe or surrounding sheet metal.

        - At the station employing balance system controls,
     the nozzle in use was an Emco-Wheaton 3003» the type
     of nozzle conditionally certified by GARB— .  The
     no-seal, no-flow feature was tested by simultaneously
I/   Includes 4 females, 8 males.

2/   Includes 5 females, 6 males.

3/   Before finally certifying the EMCO-Wheaton nozzle,
     GARB is requiring an increase in spout  length and some
     improvement in the sensitivty of the back pressure-
     shut off valve.  Neither of these modifications  should
     affect the no-seal no-flow or sealing features of the
     nozzle, however.

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                           -2-

     compressing the bellows and cocking the nozzle at an
     angle to the fillpipe.  It was determined that gas
     would flow even though the faceplate portion of the
     nozzle boot was not in contact with the entire circum-
     ference of the outer fillpipe surface—to the point
     where escaping vapors could be seen and smelled.

                                      4/
          Of the 14 customers observed—', however, none
     inserted the nozzle at a perceptible angle to the
     fillpipe, all appeared to make a good faith effort to
     shove the nozzle straight in.  Despite this fact, 4 of
     the 14 refuelings observed resulted in substantial 5/
     dripping of fuel from the nozzle/fillpipe interface— .

                 Public Reaction to Nozzles

     At the three service stations surveyed, the customers

were asked to state their feelings about the vapor recovery

system in use at the station they were patronizing.  At the

aspirator-assist station, 9 customers expressed neutral

feelings,—  2 expressed positive feelings—  and 1

                            8 /
expressed negative feelings.—  At the vacuum assist
4/   Included 1 female, 13 males.

5/   Substantial dripping means sufficient to create a
     visible pool of gasoline on the ground.  This phenomenon
     was not observed with either of the assisted recovery
     systems.

6/  E.g, "It's O.K." or "I don't mind using  it".

7/  "It's a good idea"; "I'd rather use it than breathe
     the fumes."

8/  "It squirts gas and the gas doesn't come out fast
     enough."

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                           -3-
                                         9/
station, 6 were neutral, 3 were positive,—' and one was

negative.—'At the balance system station, by contrast,

only four were neutral, one was positive,—'  and five were
         12/
negative.—'in the only formal survey performed to date of

consumer reaction to vapor recovery nozzles, Weitzman

Research Co. found a "statistically significant" preference

for the Hasselman nozzle over an OPW no latch/no flow

balance system nozzle.—'

     The conclusion that may be drawn from this data is that

public reaction to vapor recovery will depend upon the type

of system in use, with reaction to assisted'systems being

essentially neutral and reaction to balance systems being

substantially negative.
9/   E.g., "I don't get fumes; that's why I gas up here";
     "It's better for me.  I don't get spills."

10/  "I don't like it; it dumps gas out."

ll/  "It's harder to fill the tank, but I like it".

12/  "The nozzles are too heavy"; "I hate them (the nozzles).
     They're awkward to use"; "They (the nozzles) are
     ridiculous".  "I hate the nozzles.  My wife can't use
     them—they splash gas and are hard to press".

13/  Report;  Consumer Reaction to the OPW No Latch/No
     Flow Nozzle and the Hasselman Nozzle, Prepared for
     Union Oil Co. of Calif. Weitzman Research Co., December,
     1977.

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                           -4-

                   Attendant Attitudes


     During the October, 1978, field survey of vapor recovery

                                   147
systems in the District of Columbia—' , many station

attendants voiced their opinions regarding the systems.  By

an overwhelming margin, station attendants were dissatisfied

with Stage II.  Positive comments were virtually non-

existent—/.

     Negative comments related to three general areas:

inconvenience of use, high costs, and fuel spillage and

recirculation.  The heavier Stage II nozzles (all systems

in the District are balance systems), with the additionaJL

vapor recovery hoses, were cited as difficult to use,

especially for self-serve customers—.  A number of

dealers noted that the nozzles are more difficult to use on

certain vehicles, owing to particular sheet metal configur-

ations, and it was pointed out that some vehicles were

difficult to fuel because the end-of-bellows to end-of-spout

distance was not long enough.
14/  See discussion in Appendix D, pp. 4 and following.

15/  One attendant, whose attitude was otherwise negative,
     did concede that he expreienced fewer headaches since
     Stage II was put into effect at his station.

16/  One dealer claimed that his business had fallen off
     5% since the advent of the District's vapor recovery
     program, owing to self-serve customers switching to
     uncontrolled stations outside the District.

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                           -5-



     The nozzle bellows were claimed not to be very durable,



ripping rather easily on sharp vehicle sheet metal edges.



Nozzle replacement parts were said to be difficult or



impossible to obtain.  One dealer, assured that the MSED



inspector was not on an enforcement mission, confided that



he had removed some nozzle bellows—partly to avoid maintenance



costs and partly to avoid the inconvenience associated with



use of the nozzles.  Attendants pointed out that instances



of fuel recirculation occurred with existing Stage II



equipment.  In addition, many attendants, citing instances



of spills, spitbacks and leaking nozzles, questioned the



environmental benefits of Stage II.

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                               APPENDIX G

                     CUMULATIVE COST ESTIMATES

1982-1995
     The cumulative cost figures shown in Table 10 represent estimates
of the cash flow expenditures for the period 1982 through 1995.  Cash
flow was choosen as the appropriate cost indicator because this is the
least complicated (in terms of calculations) indicator of a total
expenditure pattern which is very complex because of the various phase-
in patterns assumed for each regulatory option.  The algorithm used in
these calculations is set out below in three subcategories:
     (1)  Onboard (Option III)
          This calculation was the least complex of the six options.
          (a)  No nozzle modifications:
               With no O&M expenditures this cost estimate equals the
          assumed retail price ($16.80 per vehicle) times the number of
          vehicles sold C233.1 million) over the period 1982-1995.
          (b)  With nozzle modification:
               This cost estimate adds vehicle costs ($14.40 x 233.1  million
          vehicles) and nozzle costs.   Nozzle costs include the purchase of
          new nozzles every eight years (.in 1982 and 1990) with annual
          maintenance costs and a rebuilding costs every second year.
          Some adjustment was made for an increase in the number of nozzles
          beyond 1.9 mi 11 ton.

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                            -2-
(2)   Stage II (Options  II, V, VI)
     Stage II cost estimates were  generated as follows:
     (a)   Investment cash flow:
          Using the appropriate number of stations (see  exemptions
     explained for each option), the cost figures of Appendix C
     and  the number of  nozzles per station shown in Table 9A,   ^he
     total investment cost fs simply the sum of the products  of the
     investment costs of each station and the number of  stations  in
     each stze category.   This figure is adjusted for the number  of
     new  stations  (using new station incremental costs)  which will
     replace existing stations over the period 1992-1995.
     (b)   O&M cash flow:                                      _
          Using the appropriate ttme phasing estimate this figure is
     generated by  summing the products of the annual O&M cost
     estimates of  Appendix C and the number of stations  in each size
     category.
     (c)   Adjustments:
          The investment and O&M costs are adjusted to reflect some
     growth in the number of nozzles at service stations.  This growth
     rises, but not proportionally, with the growth in the motor
     vehicle fleet.
          Total investment costs are adjusted for "adverse grade"
     as explained  in Appendix C.
          Total costs are reduced  by the size of the energy credit
     derived from  the energy saved by Stage II systems.   See
                                                              *
     Appendix B for a derivation of the cost saved per 1000 gallon
     throughput.

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                                -3-
     (3)  Onboard and Stage II (Options IV and VII)
          These simply sum the costs of Options II and III and Options
     III and VI as appropriate.
Equilibrium Costs (any 15 year period after 1995)
     The procedures followed in calculating equilibrium costs are
nearly identical to those used for the period 1982-1995.  The only
differences relate to the use of a 15 year period and to the fact that
phase-in schedules have no impact on O&M costs and the size of the
energy credit.

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