P.1 

OAR Box 1147 

Prepped by Ollie Stewart 

Document Number: 

16DIV-E-34 

Docket Number: 

A-87-11 

Printed 4/22/2008 2:42:56 PM Sheet 161 of 242 
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i> -tW- \ UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

ANN ARBOR. MICHIGAN 48105 

OFFICE OF 

AIR AND RADIATION 

MAR 3 I mo. 

MEMORANDUM 

SUBJECT: 

FROM: 

TO: 

Briefing to the Staff of the Environment and Public 

Works Committee 

Chester J. France, Chrar 

Standards Developmen' 

The Record 

On March 17, 1988, EPA staff gave a briefing to several 

staffers of the Senate's Environment and Public Works 

Committee. The briefing was requested by the committee staff 

and mainly focused on refueling emissions. The topics covered 

included the need for control of refueling emissions, refueling 

control options, and onboard hardware designs. A copy of the 

overheads used at the briefing are attached. In addition, EPA 

answered several questions concerning other mobile source 

issues such as inspection and maintenance programs, useful-life 

and vehicle emission standards. 

Attachment 
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Why Control Refuelinq Emissions? 

Provides a two percent VOC reduction 

Few remaining VOC control strategies can provide more 

reduction 

Reduction can be achieved cost effectively when compared 

to other available control alternatives 

Reduces exposure to toxic vapors during refueling -

benzene is a known human carcinogen and gasoline vapors in 

general are a concern 

Our annual incident reduction estimates for controlling 

refueling emissions are 4 with just benzene, 14 if benzene 

and >C6 are included, and 42 if benzene and all gas vapors 

are included 
T" P.4 

Refueling Options 

Onboard 

0 49 - state or nationwide strategy 

0 No exemptions 

0 2 to 3 years of manufacturers' leadtime 

0 ' Phased in as fleet turnover occurs - 50 percent in 5 years 

Stage II 

0 Nationwide or non-attainment areas only strategy 

0 Federally mandated exemptions in Clean Air Act of 10,000 

gpm majors/50,000 gpm independents. States could impose 

less generous exemption levels 

0 Installed in 3 to 7 years 
VACUUM CONTROL SOLENOID 

REFUEUNQ VAPOR 

CARBON CANISTER 

3/16 IN. 1.0. VAPOR UNE 

CONDENSATE CHECK VALVE AND 

LIQUID 8HUT-OFF VALVE 

FUEL TANK 

NOZZLE-ACTUATED 

VENT VALVE 

VACUUM PURGE VALVE 

3/4 IN. 1.0. VAPOR LINE 

X OEBl 

VAPOR/LIQUID SEPARATOR 

MKMPTMM MAT! MAL ATIC* . 

REFUEUNQ VAPOR RECOVERY SYSTEM 

CHEVROLET CAPRICE 

UUgLLgW AHOC1AT11 . IMC »Alllmor». MP 

wiio*tT|lcmt»OA/ £ ISHETIH |>AOIIO»I . 
P.6 

EVAPORATIVE/REFUELING 

VAPOR RECOVERY 

SYSTEM 

MANIFOLD PRESSURE 

VEHICLE SPEED 

COOLANT TEMPERATURE 

• • © 

RPM 

TIME 

DISTANCE 

THROTTLE POSITION 

SYSTEM COMPONENTS 

CA? 

C

*L-ER ~w5E - TCP '.ENTED 

2

 r'_:Ei. "'ANK VENT - INTERNAL PASS. CAR 

- FUEL "A\K VENT - EXTERNAL TRUCK 

i> 2iF==.=E.\r.AL PRESSURE CHECK VALVE 

6 ~uEi.TANK 

7 REFUELING VAPOR CANISTER 

8 FILTER 

3 PURGE AlR INLET - REMOTE 

PASS. CAR - REAR SUSPENSION CROSSUEUEEa 

TRUCK - UNDERHOOD 

'0 VAPCRUNE - S/8 •! D. 

: '• TANK VENT-ROLLOVER VALVE 

•2 PURGE UNE -5/"*6' 

'3 PURGE LINE - V«-

M PURGE SOLENOID - DUTY CYCLE CONTROLLED 

15 ELECTRONIC CONTROL UNIT 

16 EVAPORATIVE VAPOR CANISTER 

17 TO BI-LEVEL PURGE 

18 MANIFOLD VACUUM LINE 

19 VACUUM SOLENOID-ON/OFF 

REFUELING FILLER TUBE FEATURES: 

- NOZZLE SEALING DEVICE 

- =EFUEL;NG EVENT CEVlCE 

- PRESSURE RELiEF DEVICE.S) 

NOZZLE SHUT-OFF (LIQUID! 

VAPCR CONNECTION TO CANISTER 

LIQUID CARRYOVER PREVENTION 
Typical Current Evaporative System 

PRESSURE/VACUUM 

RELIEF CAP 

EXTERNAL VENT LINE 

tf I 

FLOAT/ROLLOVER 

VALVE 

V 

ANTI - SPITBACK 

VALVE 

/ 

3/8" DIA. 

8' LONG 

& 

PURGE VALVE 

1 LITER 

CARBON. 

CANISTER 

TO PURGE 

INDUCTION 

POINT 

FUEL TANK 
REMOVE 

Onboard Modifications 

SHORTEN 

VAPOR LINE 

MODIFY 

ENLARGE 

CARBON 

CANISTER 

. 00 
Onboard Plus Evaporative System 

PRESSURE/VACUUM 

RELIEF CAP 

NO 

EXTERNAL 

VENT LINE SHORTER 

VAPOR LINE 

V 

MODIFIE vD \ 

FLOAT/ROLLOVER 

VALVE 

X 

ANTI - SPITBACK 

VALVE 

& 

PURGE VALVE 

TO PURGE 

INDUCTION 

POINT 

ENLARGED 

CARBON 

CANISTER

 N 

FUEL TANK