OAR Box 1818 

Prepped by Ollie Stewart 

Document Number: 

4) ll-A-21 

Docket Number: 

A-87-11 

Printed 11/6/2008 3:12:41 PM Sheet 4 of 79 

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AIR POLLUTION FROM FILLING 

UNDERGROUND GASOLINE STORAGE TANKS 

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AIR POLLUTION CONTROL DISTRICT COUNTY OF LOS ANGELES 

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P.3 

3 

AIR POLLUTION FROM FILLING 

UNDERGROUND GASOLINE STORAGE TANKS 

RALPH M. BURL IN ' 

ALBERT P. FUDURICH 

DECEMBER 1962 

S. SMITH GRISWOLD 

A I R POLLUTIO N CONTROL OFFICE R 

ROBERT L. CHASS ROBERT G. LUNCHE 

DIRECTO R OF ENGINEERIN G CHIE F ENGINEE R 

AIR POLLUTION CONTROL DISTRICT - COUNTY OF LOS ANGELES 

434 SOUTH SAN PEDRO STREET, LOS ANGELES 13, CALIFORNIA 
P.4 

TABLE OF CONTENTS 

Page 

ACKNOWLEDGMENTS iii 

LIST OF FIGURES vii 

LIST OF TABLES ix 

I. INTRODUCTION 1 

H. SUMMARY . 3 

III. CONCLUSIONS 11 

IV. TEST PROGRAM DESIGN AND FACILITIES 13 

V. GASOLINE VAPOR LOSSES 19 

Filling Losses 

Breathing Losses 

Small Bulk Plant Losses 

Tank Truck Losses 

VI. DATA ON MARKETING FACILITIES '31 

Service Station Facilities 

Bulk Plant Facilities 

Tank Truck Facilities 

VII. COST ESTIMATE OF VAPOR RETURN SYSTEM .. . 41 

Service Station Costs 

Bulk Plant Costs 

Tank Truck Costs 

\T1I. EVALUATION OF NISHKIAN VALVE 47 

Description 

Operation 

Limitations 

L^\ t IA .£* .T -C* i \ E* IN V> lAO * • • • O O O • • Q • O 6 • o o • o OO 

-v-
P.5 

LIST OF FIGURES 

Page 

1. Gasoline Marketing Flow Diagram Illustrating 

Daily Losses Under Present Procedures 4 

2. Gasoline Marketing Flow Diagram Illustrating 

Daily Losses Under Proposed Vapor Return 

riUL-CUUIC O o«o0oooeaooooso«»ee « 0 

3. Experimental Vapor Return System in Operation 

During Gasoline Filling Operations at Temple and 

Grand Facility 15 

4. Vapor Return Line Manifold Mounted on Tank Truck 

±.\JJL X CoLlll t •oo*oooo»oooo»*eoo« « i u 

5. Dome Caps Modified for Returning Vapors to Tank 

Truck Compartments 17 

6. Typical Gasoline Dumping Rates for Splash Fill 

and Submerged Fill 22 

7. Typical Underground Tank Static Pressures for 

Three Types of Filling Conditions . 22 

8. Schematic Diagram of the Two Filling Techniques 

9. Breathing of Underground Gasoline Storage Tank, 

Starting with Tank Full, and Ending with Tank Empty . 26 

10. Air Pollution Control District Vapor Recovery System 

for Service Station Storage Tanks ......... . 43 

11. Exploded View of Nishkian Interlock Vapor Return 

Valve and Dip Tube ............... . 48 

12. Nishkian Return Valve Mounted on Fill Pipe .... . 50 

13. Nishkian Vapor Return Valve in Operation During Tests 51 

•vii-
LIST OF TABLES 

Page 

I. Gasoline Vapor Losses in Los Angeles County 

Resulting from Four Methods of Filling Service 

Station Underground Storage Tanks 6 

II. Cost Estimate for Modification of Existing Marketing Facilities to Accommodate a Displacement Type 

Vapor Recovery System Utilizing the Nishkian Interlock Vapor Return Valve 8 

III. Cost Per Ton of Gasoline Vapor Controlled, Using 

the Nishkian Interlock Valve 12 

IV. Average Composition of Gasoline Vapors Displaced 

from the Underground Tank During Splash and Submerged Filling Conditions. 20 

V. Gasoline Vapor Losses for Different Types of Underground Tank Filling Techniques 24 

VI. Distribution of Service Station Storage Capacities .. . 32 

VII. Distribution of Service Station Monthly Sales Volume. . 33 

VIII. Distribution of Service Station Fill Pipe Sizes .... . 34 

IX. Distribution of Service Station Distances from Fill 

Pipe to Vent Pipe 35 

X. Distribution of Service Station Vent Pipe Sizes 36 

XI. Distribution of Service Station Pumps 36 

XII. Distribution of Service Stations by Company 37 

XIII. Bulk Gasoline Loading in Los Angeles County 38 

XIV. Estimated Costs of Equipping Consumer Facilities 

with a Gasoline Vapor Recovery System 41 

-ix -
P.7 

ACKNOWLEDGMENTS 

This study could not have been completed successfully without the 

assistance and cooperation of the Shell Oil Company Bulk Loading Station, 

under the direction of Mr. Michael Davis, who generously outfitted one 

of their tank trucks and scheduled their deliveries to convenience our 

testing crews; and also of the Los Angeles County Mechanical Department who made available the facilities of the Temple and Grand Street 

station where the tests were conducted. 

Appreciation for assistance in this study is also extended to Mr. 

Joseph Sterk, who supervises the Temple and Grand Street facility; to 

Ivan S. Deckert and Robert C. Murray of the APCD Refinery Section; 

to Robert Neligan of the APCD Gas Chromatography Section; and to 

Robert Goldstein, Robert Ramlo, William Oaks, Howard Linnard and 

William Rogers of the APCD Source Testing Unit. Technical editing and 

graphic arts assistance were provided by John C. Mosher of the APCD 

Evaluation Unit, under supervision of Raymond G. Holmes. 
P.8 

I. INTRODUCTION 

As shown in the most recent total air pollution survey made by 

the APCD (I), marketing of gasoline in Los Angeles County is responsible for about 100 tons per day of hydrocarbon emissions. This amount 

is, to be sure, relatively small when compared with emissions from 

motor vehicles (approximately 1250 tons per day), for instance. However, the importance of this quantity will increase as other, larger 

sources are brought under control. As early as 1950 (2), service stations were recognized as contributing a large portion of the over-all 

marketing emissions, and their importance was underscored, in 1953, 

in the "Beckman Report" (3), which recommended early attention to 

this facet of the problem. 

Currently about 85 per cent of the bulk loading facilities are controlled under provisions of Rule 61 which became effective March 8, 

1956. Since hydrocarbons from automobiles are now in the process of 

being controlled under the jurisdiction of the State of California, hydrocarbons emitted into the atmosphere from the filling of underground 

tanks and automobile tanks remain as the only source of gasoline vapor 

emissions not under some type of regulation. 

As early as 1955, a study of feasibility of controls for this re -

maining source of emissions was initiated. In connection with this 

study, a concentric hose was developed and tested by the APCD. The 

design allowed the gasoline to flow through the inside hose, while the 

vapors displaced from the underground tank were to be returned to the 

tank truck through the annular hose. The system included some rather 

complex valve arrangements and proved to be rather bulky and heavy 

for the truck operator to handle. 

In 1957, another series of tests was initiated on a vapor control 

system submitted by M. A. Nishkian and Company. This system consisted of a vapor return valve so constructed that it enabled gasoline 

to be loaded through the center of a valve, with the gasoline vapors 

returning through a side arm directly into an activated carbon cannister. 

This series of tests was discontinued soon after its initiation because 

of the fire hazard created by overheating of the carbon cannister. 

- I -
P.9 

A somewhat similar interlock vapor return valve was submitted 

in 1961 by the same company, as an another approach to the solution 

of controlling emissions from underground tanks. In order to evaluate 

this particular valve, and any similar device which might be submitted 

at a future time, the general problem of losses during various conditions of filling of service station underground tanks was made the subject of an extensive study by the APCD. Not studied at this time were 

vapor losses from the filling of automobile tanks. 

This report presents data currently available from this study, as 

well as information relating to the economic aspects of the control of 

emissions from this source. Included are estimates of vapor losses 

during filling both with and without a recovery system, of underground 

tank breathing losses, of emissions occurring at the small, as yet uncontrolled bulk loading plants while refilling the tank trucks, and of 

the cost of equipping service stations, tank trucks, and small bulk 

plants with a postulated vapor return system. The effectiveness of the 

interlock vapor return valve, submitted by M. A. Nishkia.n and Company, was also evaluated as an integral part of the postulated recovery 

system, and the results form a part of this report. 
P.10 

n. SUMMARY 

The test program was designed and carried out in two phases: 

(1) a study of current service station filling losses, and (2) determination of variations in these losses using a vapor return system incorporating the Nishkian valve. Data were obtained with the cooperation 

of the Shell Oil Co., who furnished a tank truck to be modified and 

used in all deliveries during the test series. Shell premium gasoline 

was used in all cases, but it is believed that, for calculating tonnage 

losses, it can be considered as representative of all gasoline marketed 

in Los Angeles County. 

Current emissions from the filling of underground tanks at service stations in Los Angeles County are about 37 tons per day, assuming 

that splash loading is being used at all locations. Various combinations 

of equipment and techniques would provide control as follows (see also 

Table I): 

L.•••' 1. Reduction by nearly 40 per cent, to 23 tons per day, merely 

by converting to submerged filling techniques. 

• '/, 2. Reduction to 3 tons per day by returning the vapors to the 

tank truck, but retaining the normal vent line from the underground tank to the atmosphere. 

••••• *"', 3. Essentially complete reduction by using submerged filling, 

returning the vapors to the tank truck, and eliminating the 

atmospheric vent line. 

In addition to control of service station emissions, required auxiliary equipment would provide control of another 5 tons per day now lost 

from tank trucks in transit, and from small bulk loading plants. 

Flow diagrams, illustrating the marketing of gasoline from the 

refinery storage to the consumer, for two types of filling operations 

are shown in Figures 1 and 2. These indicate the difference in liquid 

and vapor flow between the commonly used splash fill technique and the 

suggested closed vapor recovery system. 

-3-
:S::.'.,.. 

P.11 

Legend: Gasoline Flow. Vapor Flow. 

REFINERY 

STORAGE 

6,000,000 gal 

18,600 tons 

1 ton 

Vapor lost 

in transit 

35 . 

tons 

LOO.000 gal 

12U0 tons 

•12 tons 

18,596 

tons 

RETAIL AND CONSUMER ACCOiJNTS 

19,795 

tons 

1236 

tons 

• 37 tons 

AUTOMOBILE TANK 

T 

• 2 tons 

#2 tons 

• 2 tons 

19,758 tons burned as fuel 

Figure 1. Gasoline marketing flow diagram from refinery storage to consumer 

illustrating estimated daily losses to the atmosphere under present 

operating procedures. 

-4-
P.12 

Legend: Gasoline Flow_ Vapor Flow. 

REFINERY 

STORAGE 

6,000,000 gal 

18,600 tons 

3 tons 

• 

31 

tons 

22 

tons 

URGE 

BJLK 

PLANT 

18,628 

tons 

TANK 

TRXK 

18,619 

tons 

liOO.OOO gal 

12U0 tons 

121? 

tons 

RETAIL AND CONSUMER ACCOUNTS 

19,537 

tens •• 37 tons 

AUTOMOBILE TANK 

:2 tons 

tons 

tons 

tons 

19,800 tons burned as fuel 

Figure 2. Gasoline marketing flow diagram from refinery 

storage to consumer illustrating estimated daily 

losses to the atmosphere under proposed vapor 

return operating procedures. 

-D-
P.13 

The losses from the four combinations of methods of filling 

underground tanks, as summarized in Table I, are clearly much lower 

than the emissions of 1250 tons per day from motor vehicle operations, 

and of the 300 tons per day from organic solvent usage. 

TABLE I 

GASOLINE VAPOR LOSSES IN LOS ANGELES COUNTY RESULTING 

FROM FOUR METHODS OF FILLING SERVICE STATION 

UNDERGROUND STORAGE TANKS 

FILLING 

METHOD 

Splash

 a^ 

a) Submerged ' 

Vapor Return 

Open System ^) 

Vapor. Return 

Closed System

 c ) 

Loss 

Weight 

Per Cent 

of Total Gasoline 

0.185 

O.llu 

0.013 

neg. 

GASOLINE VAPOR 

Tons 

Per Day 

37 

23 

3 

neg. 

Recovery 

(Based on splash filling loss) 

'.•/eight 

Per Cent 

0 

37 

93 

100 

Tons 

Per Day 

0 

1U 

sk 

37 

a) Venting to atnosphere. 

b) Open system venting to tank track and atr.osphere. 

c) Closed systems venting to tank track only. 
P.14 

A cost estimate for the conversion of existing facilities to accommodate a displacement type vapor recovery system utilizing the Nishkian 

Interlock Valve reveals that an initial capital investment of nearly 

$26,000,000 would be needed. Based on the 10-year project life commonly assumed for this type of equipment, this corresponds to an annual 

net investment cost (separate from maintenance) of $3,708,000, and 

would necessitate a price increase of 0.16 cents for each gallon of gasoline sold in order to recover this annual cost. These data are summarized in Table II. 

Some of the attractive features of a vapor return system are: 

1. There is a 15 to 20 per cent increase in dump rate due to 

reduced pressure in the underground tank and increased 

static head. 

2. There is an absence of gasoline odors during the filling 

operation. 

3. Vapor losses are reduced. 

4. The undesirable and hazardous splash fill technique is 

eliminated. 

5. The utilization of a tightly sealed, leak-proof connection 

to the underground tank minimizes the possibility of accidental spills during loading. 

6. There is a concomitant reduction in fire hazard. 

However, many problems would have to be overcome before the 

use of a vapor return system could become widespread. The most important of these are: 

1. The various systems in existence would have to be standardized throughout the entire industry, especially as to equipment installed on trucks, so that "for hire" carriers could 

not be limited as to the supplier. 

2. Systems would have to be designed to meet all necessary 

specifications such as vacuum limitations of tank truck 

compartments. 
TABLE II 

COST ESTIMATE FOR MODIFICATION OF EXISTING MARKETING FACILITIES 

TO ACCOMMODATE A DISPLACEMENT TYPE VAPOR RECOVERY SYSTEM 

UTILIZING THE NISHKIAN INTERLOCK VAPOR RETURN VALVE 

OO 

FACILITY 

Retail Service Stations 

Consumor Accounts 

Small Bulk Plants 

Large Bulk Plants 

Tank Trucks 

Total 

GASOLINE 

HANDLED 

{% of total 

volume) 

95 

5 

6 

914 

100 

PRESENT 

GASOLINE 

VAPOR 

LOSS 

(tons/day) 

35 

2 

2 

3 

3 

U5 

GASOLINE VAPOR 

RECLAIMED AT 

FACILITY <0 

(tons/day) 

13d) 

id) 

2 

2i,d) 

2 

U2 

INITIAL 

CAPITAL 

INVESTMENT

 b ) 

(dollars) 

17,190,000 

6,500,000 

35,000 

None 

1,990,000 

25,723,000 

ANNUAL COST 

OF 

INITIAL 

INVESTMENT °) 

(dollars) 

2,808,000 

1,092,000 

6,000 

None 

335,000 

h,321,000 

ANNUAL 

RETURN FROM 

VAPORS RECOVERED AT $i40/T0N 

(dollars) 

190,000 

15,000 

29,000 

350,000 

29,000 

613,000 

NET 

ANNUAL 

COST (OR 

RETURN) 

(dollars) 

2,698,000 

1,077,000 

23,000 

(Return) 

350,000 

(Return) 

306,000 

3,708,000 

NET COST (OR 

RBTURN)/QALL0N 

GASOLINE 

HANDLED 

(mils) 

1.2 

9.2 

0.2 

(Return) 

0.2 

(Return) 

0.1 

1.6 

a) Based on Vapor Recovory of I4.2 pounds per 1000 gallons at retail and consumer accounts, and 7.3 pounds per 1000 gallons at bulk 

plants out of total of 11.5 pounds per 1000 gallons produced. 

b) Capital investment is for displacement vapor recovery system which includes Nishkian inerlock valve, vapor return hose and 

fittings as required. 

c) Based on 10-year life of project, 6,6 rate of return, 2.5^ franchise and real estate taxes, and sinking fund factor at 8.3 based 

on h% interest for life of project: 

Annual Cost - 6.0 * 2.5 + 8.3 x initla l caplta l C03 t 

100 

d) Under proposed system, part of the gasoline is reclaimed by condensation in the service station storage tank, but the majority 

is reclaimed at the bulk plant. 
P.16 

31---

3. Systems would have to be designed to comply with jurisdictional governmental safety regulations pertaining to fire and 

other hazards. 

4. Necessary air pollution legislation would have to be enacted 

to require that such a program be put into effect. This legislation would have to specify the extent of coverage of the control requirements. 

5. A partial control program would be impractical unless there 

were standardization and/or interchangeability of all equipment in present use. 

6. Systems would have to be completely vapor-tight to prevent 

vapor escape at ground level. The more prominent source 

of leaks would be at the hatch covers on the tank truck compartments. 

7. The equities involved in requiring large expenditures to control rather small quantities of air contaminants at any one 

source would have to be carefully weighed. 

• 9 -
P.17 

1 • 

III. CONCLUSIONS 

By adoption of a complete vapor recovery system, an estimated 

42 tons per day of hydrocarbon vapors (37 from service stations, 5 

from transfer sources) could be prevented from entering the atmosphere in Los Angeles County. 

To achieve this, the entire marketing industry would have to participate, with equipment changes and financial expenditures required by 

retail and consumer service station accounts, by bulk plants, and by 

tank trucks. 

An initial capital investment of about $26,000,000 would be necessary, amounting to a net annual cost of over S3, 700,000, prorated over 

a 10-year period. Over 90 per cent of the total capital expenditure 

would be made by the retail and consumer accounts, who would realize 

no net return on their investment. Contrasted to this, the initial capital investment by the bulk plants and tank trucks would amount to less 

than 10 per cent of the total, with only the bulk plants showing a net 

return on their investment. 

As detailed in Table III, the net annual cost per ton for controlling 

these vapors would be extremely high, with the over-all net annual cost 

to the entire marketing industry mounting to some S88,000 per ton of 

gasoline controlled. (In more familiar quantities, this would be about 

$275 per gallon.) 

Whether the expenditures enumerated would be justified to correct this loss to the atmosphere is a decision beyond the scope of this 

report. However, as other sources of hydrocarbon losses come increasingly under control, this source will represent a growing portion 

of the total that remains uncontrolled and, thus, could merit serious 

consideration. 

The Nishkian valve, itself, was found to operate in a satisfactory 

manner as a component of the total vapor recovery system studied; it 

is not, however, a complete control system of and by itself. Its incorporation into an integrated system would provide a complete measure 

of control, provided the expenditures were judged justifiable. 

i l -
P.18 

It should be emphasized that the above system in no way provides 

control for the equivalent amount of gasoline vapors emitted during the 

filling of automobile tanks at the service stations. Such control would 

require development of appropriate equipment and further expenditures 

by the service stations. 

TABLE III 

COST PER TON OF GASOLINE VAPOR CONTROLLED, USING THE 

NISHKIAN INTERLOCK VALVE 

FACILITY 

Retail Service Stations 

Consumer Accounts 

Large Bulk Plants 

Small Bulk Plants 

Tank Trucks 

Entire Marketing Sources 

GASOLINE 

HANDLED 

(,% of total 

volume) 

95 

5 

9U 

6 

100 

PRESENT 

VAPOR LOSS 

(tons/da7) 

35 

2 

3 

2 

3 

NET ANNUAL COST 

(OR RETURN) FOR 

CONTROL a) 

(dollars) 

2,698,000 

1,077,000 

(350,000) 

(Return) 

(23,000) 

(Return) 

306,000 

3,708,000 

NET ANNUAL COST 

(OR RETURN)/TON/ 

DAY OF VAPORS 

CONTROLLED 

(dollars) 

77,000 

538,000 

(b) 

(12,000) 

(Return) 

112,000 

88,000 

a) Based on 10-year amortization of initial cost, and calculated by formula 

detailed in Table II. 

b) Net annual return is accrued with no additional vapor controls for this facility. 

-12-
P.19 

IV. TEST PROGRAM DESIGN AND FACILITIES 

The testing program was designed and carried out in two phases. 

Phase one was conducted to obtain background information on tank 

breathing and filling losses from existing facilities as they are presently 

equipped without vapor control equipment or other modifications. Phase 

two was performed to obtain comparative information on losses when 

using splash filling, sugmerged filling, and filling utilizing the Nishkian 

valve and a vapor return system. 

During each phase, samples were collected and measurements 

were made as follows: 

1. The temperature of the gas and liquid phase in the underground tank, and the atmospheric temperature, were 

simultaneously monitored for a seven-day period. 

2. Samples for determination of vapor composition were collected daily from the vapor phase of the underground tank 

for a seven-day period between fills. These vapor samples 

were collected at the top, middle, and bottom of the vapor 

phase to determine whether stratification in composition 

exists. 

3. The program for each of the gasoline dumps made during the 

testing program was as follows: 

a. The gasoline dump rate and the total amount dumped 

were recorded. 

b. The flow rate and the total volume of gasoline vapor 

displaced were measured. 

c. Gasoline vapor samples were collected from the underground tank, the tank truck, and the vapor vent line both 

when venting to the atmosphere or when returning the 

vapors to the tank truck. 

-13-
P.20 

d. The ambient air temperature was recorded. 

e. The liquid gasoline temperatures were measured in 

the underground tank and in the tank truck both at the 

beginning and end of each dump. 

f. Samples of the gasoline being dumped and of the gasoline in the underground tank, both before and after the 

dump, were collected. 

g. Static pressures were measured in the vent line, the 

underground tank, and the tank truck during each dump. 

The tests were conducted at the Los Angeles County-owned service station facilities at Temple and Grand Streets. These consist of 

two pumps for delivering gasoline to County vehicles and a single underground storage tank with one atmospheric vent line. 

About midway through the testing program it was discovered that 

the underground tank at this station was not the standard type in general 

use at regular service stations. This tank is 43 feet in length and 5 feet 

in diameter, with a capacity of approximately 6, 500 gallons, while 

standard tanks of the same capacity are 17 feet in length and S feet in 

diameter. It is possible that the data on breathing losses for this particular tank might not be wholly representative of data from the standard tanks because of the various factors that affect these losses. It is 

believed, however, that the differences would be small and would not 

substantially affect the over-all results. 

One truck, to be used for all of the gasoline deliveries to the 

Temple and Grand Street station, was assigned by the Shell Oil Company 

for the test series. The District purchased modified tank truck dome 

caps and the necessary fittings, and Shell assembled and installed this 

equipment to make up the vapor return system. The complete vapor 

return system is shown in operation in Figure 3, while Figure 4 provides a close-up view of the vapor return manifold as mounted on the 

tank truck. Each dome cap (see Figure 5) was equipped with two spring 

loaded relief valves. One was a vacuum relief valve usually set for 

about 7 inches water column, and the other was a pressure relief valve 

which was set to open at 3 to 5 psig pressure. The vapor return line 

was connected to the vacuum relief valve port; the relief valve, itself, 

was left intact and in operative condition.. An additional fitting was installed in each dome cap for collecting vapor samples and reading tank 

pressures. 

14-
OI 

Figure 3. Experimental vapor return system in operation during gasoline filling operations at 

Temple and Grand facility. Pressures are being measured in the tank truck compartments, and the gas flow is being determined with a viscous flow meter apparatus. 

1. Tank vapor manifold 

2. Gasoline fill hose 

3. Vapor return hose 

4. Viscous flow meter 
I 

Figure i|. Vapor return line manifold mounted on tank truck for testing. 
P.23 

r 

'• :••:•£-.•.• &.y3 "'•:&: 

-'•• - . -;•'.«*'•. • • , . 

•>^: . r-w V •--•;••:.•'.•. •/• 

• .. s-!/<Ay>+:y>;;-.;.. 

'.• \*a*-, <': •• 

fr ;••-.?'.••. 

Figure 5. Dome caps modified for returning vapors to tank truck compartments. 

1. Vapor outlet line 

2. Vapor outlet for pressure measurements or sampling. 

17' 
P.24 H 

As part of the connection between the tank truck and the underground tank, a valve submitted by Nishkian and Company was used. 

This was an interlock arrangement, so constructed as to enable gasoline to be loaded into the tank through the center of the valve, with 

vapors being returned to the tank truck through a side arm. A more 

detailed description of the system is given in Section VIII of this report. 

Four different types of underground tank fills were made. These 

were the splash or top fill, with the vapors normally vented to the atmosphere through the vent pipe; the submerged or bottom fill, in which 

the gasoline was introduced into the tank through a fill tube extending 

to approximately six inches from the bottom of the tank, and with the 

vapors venting to the atmosphere; a submerged fill with a vapor return 

system, but with the underground tank vent line open to the atmosphere; 

and the same fill with a completely closed vapor return system. The 

latter two types of fills, utilizing vapor return systems, involved the 

use of the Nishkian valve. 

18-
P.25 

V. GASOLINE VAPOR LOSSES 

Filling Losses 

Filling losses are dependent upon certain system or equipment 

variables such as the size and length of the vent pipe, the diameter of 

the fill pipe, the method of filling, and the tank configuration. Other 

conditions affecting filling losses are the temperature, vapor pressure, 

and composition of the gasoline. For this test series, the only experimental condition deliberately varied was the method of filling. 

When using a top or splash fill, the gasoline enters the top of the 

fill pipe and then has a free fall to the liquid surface in the tank. This 

free falling tends to break up the liquid stream into droplets. As these 

droplets strike the liquid surface, they carry entrained air into the 

liquid and a "boiling" action results as this air escapes up through the 

liquid surface. The net effect of these actions is the creation of additional vapors in the underground tank. 

When the tank is bottom filled using a submerged fill pipe, the 

gasoline flows to the bottom of the tank through the fill pipe and enters 

below the surface of the liquid. This method of filling creates very 

little disturbance in the liquid bath and consequently less vapor formation than splash filling, except during the initial stages of filling when 

the liquid level may be below the end of the fill pipe. The fill pipe 

usually extends to within six inches of the bottom of the tank. The 

differences between the concentrations of vapors when using the two 

filling methods are appreciable, as may be seen by referring to Table 

IV. Averages of the tests conducted show that splash filling resulted 

in a volumetric increase of vapors of more than 15 per cent over that 

present when using the submerged filling technique. (Differences also 

appear in the composition of the vapors associated with the two methods, 

and are shown in Table IV. It is problematical, however, whether these 

differences in composition are significant to the air pollution problem.) 

A significant feature of the submerged type of fill used in conjunction with a vapor return system is the increase in filling rate over that 

-19-
P.26 

TABLE IV 

AVERAGE COMPOSITION OF GASOLINE VAPORS DISPUCED 

FROM THE UNDERGROUND TANK DURING SPLASH 

AND SUBMERGED FILLING CONDITIONS 

COMPONENT 

Air 

Hydrocarbons 

Analysis of Hydrocarbons 

Methane 

Ethane and ethylene 

Propane and acetylene 

Propene 

Isobutane 

ri-Butane 

1-Butene, isobutylene and methyl acetylene 

trans-2-Butene 

cis-2-Butene 

Isopentane 

n.-Pentane 

1-Pentene 

2-Methyl-l-butene 

2,2-Di-nethylbutane and trans-2-pentene 

cis-2-Pentene 

2-Kethyl-2-butene 

2,3-Dimethylbutane and 2-methylpentane 

3-Methylpentane and cyclcpentane 

Cyclopentane 

n-Hexane — A 

2 , It-Dime thylpentane 

3-Methylhexane 

2,3-Dimethylpentane 

3-Kethylhexane 

2,2,1(-Trime thylpentane 

2-Methyl-l-pentene 

trans-2-Kexene 

cis-2-Hexene ) 

cis-3-Hexene 

Cyclopentene 

Eenzene 

Toluene 

m- and _o-Xylene 

o.-Xylene 

Methylcyclopentane 

Cyclohexane — ^ 

SPLASH 

FILL 

(volume %) 

60.8 

39*2 

lU.o 

Ii.7 

3.2 

0.7 

3.6 

33.6 

0.7 

0.8 

0.6 

17.5 

5.? 

0.3 

0.? 

1.0 

OA 

1.8 

2.1 

l.U 

03} 

0.5 

6.1 

SUBMERGED 

FILL 

(volume fi) 

66.1 

33.9 

11.3 

5.1 

3.9 

0.6 

3.7 

35.8 

-03$ 

0.9 

0.7 

15.8 

7.2 

'0.1; 

0.5 

1.2 

0.6 

1.1 

2.3 

1.7 

0.1; 

0.7 

5.6 

•20-
P.27 

of the splash type of filling. The graph in Figure 6 illustrates the 

difference between the dumping rates for these two fill conditions; 

underground tank static pressures for splash filling, and for submerged 

filling using both types of vapor recovery, are shown in Figure 7. 

Naturally, with either splash or submerged filling, any vapors formed 

in the tank space above the liquid level are compressed and forced out 

the vent pipe to the atmosphere as the gasoline level in the tank rises. 

When employing a vapor return system in conjunction with filling 

the underground tank, the vapor space of the tank is connected directly 

to the vapor space of the tank truck compartments by means of the 

interlock valve and the necessary hose and fittings. For this study, the 

vapors were returned to the truck compartment through the vacuum 

relief valve located in the hatch cover. Thus, instead of displacement 

air being drawn into the tank truck compartment from the atmosphere 

as it normally would, gasoline vapors were drawn into the compartments from the underground tank, thus preventing these vapors from 

being released to the atmosphere. Vapor return fills were made both 

with and without the underground tank atmosphere vent line open. Figure 8 illustrates the mechanisms of a splash fill and a vapor return 

submerged fill. 

Three methods may be used for connecting the truck hose to the 

tank fill pipe; these are classified as loose, speed cone, and tight connections. With the loose connection there is no seal between the trucK 

hose and the fill pipe. The speed cone connection consists of a coneshaped rubber gasket which seals or partially seals the annular space 

between the hose and fill pipe. For the tight connection, a leak-proof, 

quick-connect coupling is used between the hose and the fill pipe. A 

vapor return system would require a tight connection, with standardized 

parts that would be interchangeable for all trucks, tanks, and bulk plants. 

The speed cone connection is now normally used for filling underground tanks. Usually n^)_dip_tube is present, so splash filling takes 

place. With this technique (as shown in Table V which summarizes the 

vapor losses and potential recovery for the different fill techniques 

tested), gasoline vapor losses amount to 11.5 pounds for each 1000 gallons of gasoline delivered. Use of the submerged filling procedure 

would reduce this loss by approximately 37 per cent. With a vapor re -

turn system in which the underground tank vent line is left open, the 

losses are reduced by 93 per cent. If a displacement type, closed vapor 

return system is employed, the losses can be completely eliminated. 

However, these recovery values refer only to the transfer of the gasoline from the tank truck to the underground tank and can only be totally 

realized if the truck compartments are adequately sealed and there is a 

vapor recovery system at the bulk loading terminal. 

•21-
P.28 

200 

160-

•a 

u 

a> a 

OJ 

C 

o 

H 120 -

60 

8 

Submerged 

Filling 

i 

16 

Splash 

Filling 

24 40 32 

Elapsed Time From Start of Gasoline Fil l (minutes) 

Figure 6. Typical gasoline dumping rates for splash fil l and submerged 

fill . 

Splash fillin g 

Avg rat e 121 gpm 

® 

b 

01 

0) 

tt 

.." a -—- ~ —- - or — 

•. .• •. \ i..... "•*-.. / 

y^'- *• :V. I 

Vapor recovery * \ .• " Vapor 

Open system 

Avg rat e 150 gpm 

12 16 20 24 28 32 36 40 44 48 

Elapsed Time From Start of Gasoline Fil l (minutes) 

Figure 7. Typical underground tank stati c pressures for three types of 

filling conditions. 

•22 -
Current Technique; 

Splash Filling 

Vapors Vented to Air 

Proposed Control Technique: 

Submerged Filling 

Vapors Returned to Truck 

• Vapors To Atmosphere 

CO 

I 

XT r-r 

°A>'°~ 

) 

Vapor Return Manifold 

Gasoline drains by gravity flow from the 

tank truck compartments through a meter. The 

gasoline ha3 a free fall from the hose nozzle 

to the liquid surface of the tank, causing a 

boiling action of the liquid. Air enters the 

compartments through the vacuum relief valves 

in the dome caps to replace the gasoline. 

Vapors from the underground tank are lost to 

the atmosphere. 

Gasoline drains by gravity flow from the 

compartments through the meter and a fill pipe 

extending below the liquid surface, resulting 

in a minimum agitation of the liquid. Vapors 

from the underground tank return to the tank 

truck through the annular space of the interlock valve into the manifold and the vacuum 

relief valves in the dome cap. 

Figure 8. Schematic diagram of the two filling techniques used in this study. 
P.30 

TABLE V 

GASOLINE VAPOR LOSSES FOR DIFFERENT 

TYPES OF UNDERGROUND TANK FILLING TECHNIQUES 

(Per each 1000 gallons gasoline delivered) 

TYPE OF 

FILL 

Splash 

Submerged 

Vapor ReturnOpen System 

Vapor ReturnClosed System 

VOLUME RATIO 

VAPOR FORMED 

TO GASOLINE 

DUMPED 

l.U to 1 

1 to 1 

1.1 to 1 

1 to 1 

Concentration 

In Gas 

Phase 

(vol %) 

39 

V 

3U 

x 3U 

GASOLINE VAPOR 

cu ft 

73 

U6 

5 

0 

Loss 

lb 

11.5 

7.3 

0.8 

0 

vt % 

0.19 

0.12 

0.013 

0 

Recovery 

(Based on splash 

fill loss) 

cu ft 

0 

27 

68 

73 

lb 

0 

li.2 

10.7 

11.5 

vt % 

0 

37 

93 

100 

Breathing Losses 

In this report, breathing of underground tanks refers to the inhaling of air and exhaling of a vapor-air mixture through the vent pipe during normal pumping operation. These emissions are independent of 

vapor emissions that occur during refilling of the underground tank. 

When an automobile is fueled, gasoline is pumped from the underground tank, causing air to be inhaled through the vent pipe, the volume 

being approximately equal to the volume of gasoline withdrawn. The air 

then becomes saturated, more or less rapidly, with gasoline vapors, and 

thus tends to occupy a larger volume. This in turn causes the vapor-air 

mixture to exhaust from the underground tank until a pressure equilibrium is attained. 

-24-
Theoretically, two cubic feet of excess vapor-air mixture are 

exhaled for every three cubic feet of air inhaled during pumping operations, amounting to a loss of about 6 pounds of gasoline vapors per 1000 

gallons pumped, or about 0.1 per cent by weight. This calculation assumes the incoming air will become saturated with gasoline vapors to a 

40 volume per cent level, and that the resulting mixture is exhaled in a 

relatively short time. This is not true in practice under normal service station operation, in which gasoline is pumped at a rate of approximately 10 gallons per minute. Under these relatively slow pumping 

conditions, air is continuously inhaled during a cycle, and becomes 

partially saturated before the pumping is completed. This results in a 

smaller volume of air being inhaled than the volume of gasoline being 

withdrawn, and consequently less volume of air being exhaled after completion of the pumping cycle. 

At times when the underground tank is full, exhaling occurs immediately after the pumping period, and at a rather high flow rate. 

When the tank is less than half full, the exhaling action is slow in starting, and has a very low flow rate. Because of these variations in flow 

rate, and the intermittent nature of the occurrence, it was impractical, 

in this study, to collect representative vapor samples for analysis. 

Consequently, the theoretical value of 40 per cent gasoline vapor in the 

exhaled mixture was applied to the measured volume to obtain the estimated breathing losses. These emissions were calculated to be about 

one-sixth of the theoretical weight, or less than 1 pound per 1000 gallons of gasoline pumped. 

Factors affecting the breathing losses are complex and interrelated, depending upon the service station operation, gasoline pumping 

rate, frequency of pumping, ratio of liquid surface to vapor volume, 

diffusion and mixing of air and gasoline vapors, vapor pressure and 

temperature of the gasoline, the volume and configuration of the tank, 

and the size and length of the vent pipe. Because of these many variables involved, much more data from a number of representative retail 

stations would be necessary before an accurate determination of overall, Basin-wide breathing losses could be made. Using the data available, the estimate for the County is about 3 tons per day, and this small 

amount could be practically eliminated by the installation of a combination pressure-vacuum valve on existing vent lines from the underground 

tanks. 

Experimental results of the breathing loss study on the underground tank at the Temple and Grand Street facility during a regular 6- • 

day period between fills are shown graphically in Figure 9. 

•25-
^ 

f\ 

\

 v 

-26-

V. 

l' 

900 -

800 -

700 -

600 -

-H 

£50 0 -

o 

•H 

3 400 -

300 -

200 -

100 -

0 

Figure 

Final volume 

^79 6 cu ft 

^ y (5960 gal) 

X Final volume 

/ ^51 3 cu f t 

Gasoline pumped X/ ^' y 

^00^^ Air inhaled y 

/ ^,*'''*" Fina l volume 

Day 1 ' hay 2 ' Day 3 ' Day 4 ' Day 5 ' Day 6 ' Day 7 

9. Breathing of underground gasoline storage tank, startin g a t tank full condition (6315 

gallons) and ending with the tank empty (insufficien t for pumping). The underground 

tank used is the facilit y a t Temple and Grand streets. Dimensions are U3 fee t by $ 

feet, with approximately 70 feet of 1^ inch vent line . 

-
P.33 

!• 

During the course of conducting the breathing loss study, data was 

obtained relative to temperature variations of the liquid and vapor phase 

in the underground tank during a 7-day period. During this same period 

the vapor phase was monitored daily to determine whether the composition of the vapor phase varied with time and with the amount of gasoline 

in the tank, and whether the composition varied from the top to the bottom of the vapor phase. The analyses indicated no apparent change in 

vapor concentration with respect to any of the above-mentioned factors. 

The vapor temperature was found to vary about 2 F daily during 

the period between deliveries, generally reaching its maximum about 

2:00 A.M. and its minimum about 2:00 P.M. The vapor temperature in 

the underground tank was usually 4 to 6 F higher than the liquid temperature. During a two-month period (March-April 1962), temperature 

data taken during five gasoline deliveries indicated that the temperature 

of the gasoline being delivered increased an average of 1 F during the 

dump, and that the temperature of the gasoline in the underground tank 

increased an average of 7 F. At the times the five deliveries were being 

made, the air temperature averaged 75 F, the gasoline temperature in 

the underground tank before delivery averaged 68 F, and the gasoline 

temperature in the tank truck before dumping averaged 74 F. 

The vapors in the underground tank were generally 3 F lower and 

the tank truck vapors were generally 3 F higher than the daytime ambient 

atmospheric temperature. The higher temperatures of the truck vapors 

were caused by exposure of the tank truck to the sun's rays. 

The gasoline temperature in the underground tank did not vary 

appreciably between deliveries, afjer an initial temperature drop during the first day after the delivery. The magnitude of this initial 

adjustment depends upon the temperatures of the delivered gasoline, of 

the tank gasoline, and of the surrounding environment. 

Small Bulk Plant Losses 

Vapor losses from small bulk plants are calculated to be about 

2 tons per day, based on estimates that they handle 6 per cent of the 

total consumption of gasoline in Los Angeles County, or approximately 

400,000 gallons per day. Since most of the small bulk plants use a 

submerged fill pipe for loading the tank trucks, it is further assumed 

that the rate of vapor formation during this loading should be the same 

as that from filling an underground storage tank, using the same technique. As previously shown (see Table V) this amounts to 7.3 pounds 

-27-
P.34 

of vapor for each 1,000 gallons of gasoline handled. These losses would 

be reduced nearly 100 per cent, if the bulk plants were equipped with a 

simple displacement type vapor recovery system, used in conjunction 

with modified tank trucks. 

Tank Truck Losses 

No determinations were made, in this study, of actual losses from 

tank trucks while in transit to and from the bulk plants. However, a 

previous study of one truck indicated that the amount of losses which 

occur would be dependent on the distance between the service station 

and bulk plant, the ambient temperature, the tightness of the dome cap 

closure, the composition of the gasoline, and the amount of gasoline 

remaining in the compartment after a dump. 

The composition of these losses is somewhat speculative. Gas 

samples taken during this survey from an empty truck compartment immediately after a gasoline delivery indicated a gasoline vapor concentration of 3 to 5 per cent by volume. If the compartment were completely 

emptied and dry, this vapor concentration would not change materially 

until the compartment was refilled at the bulk loading terminal. In 

practice however, complete emptying of the truck compartment does 

not occur. There is always some hang-up of liquid gasoline in the 

truck compartments after a delivery. 

This remaining liquid volatilizes to a degree governed by the 

residual volume, the ambient temperature, the agitation of the liquid, 

and the transit time between the service station and the bulk plant. 

Usually these conditions are such that only partial saturation of the 

vapor space by gasoline vapors is obtained. However, the degree of 

saturation which does occur results in one of two circumstances: either 

there is a pressure build-up in the compartment, or the partially saturated vapor escapes to the atmosphere, depending on the tightness of the 

dome caps. 

If the compartment is gas tight, the pressure is released when the 

hatch covers are opened for refilling, and the vapors are lost to the atmosphere. For short trips the amount of vapors emitted would be essentially the same in either case. In cases where saturation were 

reached, the loss would be greater from compartments with loose -fitting 

lids, since it would be a continuing process. In theory, assuming the 

compartments were gas tight and saturation was reached, 80 tons per 

day could be lost in delivery and return to all bulk plants. In actual 

-28-
P.35 

hatch ^TZSZ^tto T

 VariaU°n Wa s

 ^ » the flt of th 

Proof, with pressures beSTM^.^*TM6, "

 wa* 'ound to be almost- iOQu 

•29-
P.36 

VI. DATA ON MARKETING FACILITIES 

Service Station Facilities 

Service station data used for this study was extrapolated from a 

field survey conducted by APCD personnel in 1958. A listing of the number of service stations and the number of pumps in Los Angeles County, 

with a breakdown by municipalities, was received in a communication 

dated April 30, 1958, from the State of California, Department of Agriculture, Bureau of Weights and Measures. From this list, 122 were 

selected for a detailed field survey by combining the municipalities into 

areas, and determining the total number of stations in each area. The 

telephone book representing each area was taken, and every fiftieth 

service station, as listed alphabetically in the book, was selected for 

inspection. 

Distributions of these 122 stations according to storage tank capacities and monthly sales volume are shown in Tables VI and VII. It may 

also be noted that the average station surveyed had 3 underground tanks, 

with a median sales volume of 20,000 gallons per month. 

In addition to these retail stations, there also are approximately 

10,000 consumer accounts, dispensing about 5 per cent of the total gasoline volume. Facilities at these consumer accounts usually consist of 

one tank and one pump. 

From reports of the taxable sales issued by the State Board of 

Equalization, and from the vehicle registration data furnished by the 

State Department of Motor Vehicles, it is estimated that, as of January 

1, 1962, nearly 192,000,000 gallons of motor gasoline were used each 

month in Los Angeles County. Subtracting the 5 per cent dispensed 

through consumer accounts shows that 182,000,000 gallons per month 

are sold by retail stations. Using the median sales volume of 20,000 

gallons per month per station determined from the early survey, and 

the 182,000,000 gallons per month total sold in Los Angeles County, a 

projected estimate of 9100 retail stations is obtained for the County for 

January 1962. 

-31-
TA3LE VI 

DISTRIBUTION OF SERVICE STATION STORAGE TANK CAPACITIES

 a ) 

NOMINAL TANK SIZE 

(gallons) 

280 

500 

750— 

1000 

1500 

2000 

2500 

3000 

3500 

Uooo 

5ooo 

55oo 

6000 

6500 

7000 

7500 

8000 

10000 

Total 

NUMBER OF TANKS 

2 

U7 

1-

73 

3 

U9 

6 

12 

6 

95 

38 

1 

23 

1 

1 

8 

1 

15 

382 

PER CENT 

0.5 

12.3 

0.3 

19.1 

0.8 

12.8 

1.6 

3.1 

1.6 

24.8 

9.9 

0.3 

6.0 

0.3 

0.3 

2.1 

0.3 

3.9 

100.0 

CUMULATIVE 

PER CENT 

0.5 

12.8 

13.1 

32.2 

33.0 

1*5.8 

U7.U 

50.5 

52.1 

76.9 

86.8 

87.1 

93.1 

93.U 

93.7 

95.8 

96.1 

100.0 

a) From field survey of 122 stations. 

•32-
P.38 

TABLE VII 

DISTRIBUTION OF SERVICE STATION MONTHLY SALES VOLUME

 a ) 

MONTHLY SALES 

(gallons) 

<u000 

1*000-71*99 

7500-9999 

10,000-121*99 

12,500-11*999 

15,000-171*99 

17,500-19999 

20,000-21*999 

25,000-29999 

30,000-31*999 

35,000-39999 

1*0,000-1*9999 

50,000-71*999 

> 75000 

Total 

NUMBER OF 

STATIONS 

3 

11 

8 

12 

8 

11 

8 

19 

11 

12 

5 

5 

7 

2 

122 

PER CENT 

2.5 

9.0 

6.6 

9.8 

6.6 

9.0 

6.6 

15.6 

9.0 

9.8 

U.l 

U.l 

5.7 

1.6 

100.0 

.CUMULATIVE 

PER CENT 

2.5 

n.5 

18.1 

27.9 

3U.5 

1*3.5 

50.1 

65.7 

71*. 7 

81*.5 

88.6 

92.7 

98.1* 

100.0 

TOTAL SALES 

(gallons) 

9,750 

71,100 

69,600 

135,000 

107,500 

172,000 

11*6,500 

Ul7,000 

289,000 

370,500 

223,000 

213,000 

U08,700 

165,000 

2,799,650 

PER CENT 

0.3 

2.5 

2.5 

1*.8 

3.8 

6.2 

5.2 

ll*.9 

10.3 

13.2 

8.0 

7.6 

ll*.6 

SA 

99A 

CUMULATIVE 

PER CENT 

0.3 

2.8 

5.3 

10.1 

13.9 

20.1 

25.3 

U0.2 

50.5 

63.7 

71.7 

79.3 

93.9 

99.9 

a) From field survey of 122 stations. 

-33-
Based on the average of 3.1 tanks per retail station determined 

from the field survey, there are an estimated 28,200 underground tanks 

at the retail stations. These, plus the 10,000 tanks at consumer account locations, give a total of 38,200 underground storage tanks currently being used in the dispensing of gasoline in Los Angeles County. 

Should existing systems be converted to a vapor return system 

incorporating a unit such as the Nishkian valve, the size of the existing 

fill pipes would become a major factor for consideration. The distribution of fill pipe size for the stations inspected in the field survey is 

shown in Table VIII. It can be seen that diameters range from 2 inches 

to 6 inches, with 19 per cent being less than 3 inches. This latter value 

is the minimum diameter that can be used with the Nishkian valve, with 

anything smaller requiring the installation of a new fill pipe, preferably 

of 4-inch size. 

TABLE Vi n 

DISTRIBUTION OF SERVICE STATION FILL PIPE SIZES

 a ) 

DIAMETER 

(inches) 

2 

2i3 

31 

U 

Ui 

6 

Total 

NUM3ER OF PIPES 

66 

U 

185 

10 

95 

1 

1 

362 

PER CENT 

18.2 

1.1 

51.1 

2.8 

26.2 

0.3 

0.3 

100.0 

a) From field survey at 122 stations. 

-34-
P.40 

During the service station survey, data also were collected on 

the distribution according to vent pipe size, distance of fill pipe to vent 

pipe, number of pumps per station, and company. This information is 

presented in Tables IX to XII respectively. 

TABLE DC 

DISTRIBUTION OF SERVICE STATION DISTANCES 

FROM FILL PIPE TO VENT PIPE

 a ) 

DISTANCE 

(feet) 

0-9 

10-19 

20-29 

30-39 

U0-U9 

50-59 

60-69 

70-79 

80-89 

90-99 

Tota l 

NUMBER 

VENT PIPES 

21 

99 

73 

83 

27 

1U 

26 

13 

5 

1 

362 

PER CENT 

5.8 

27.3 

20.2 

22.9 

7.U 

3.9 

7.2 

3.6 

l.U 

0.3 

100.0 

CUMULATIVE 

PER CENT 

5.8 

33.1 

53.3 

76.2 

83.6 

87.6 

9U.7 

98.3 

99.7 

100.0 

a) From field survey of 122 stations 

•35-
P.41 

TABLE X 

DISTRIBUTION OF SERVICE STATION.VENT PIPE SIZES

 a^ 

NOMINAL 

PIPE SIZE 

1 

If 

if 

2 

2* 

3 

Total 

NUMBER 

VENT PIPES 

30 

11*1 

151 

U9 

1 

2 

37U 

"'" ' PER CENT ' " '' 

8.0 

37.7' 

UO.U 

13.1 

0.3 

0.5 

100.0 

' CUMULATIVE 

PEP. CENT 

8.0 

U5.7 

86.1 

99.2 

99.5 

100.0 

a) From field survey of 122 stations - 2, • i -

TABLE XI 

NUMBER PUMPS 

PER STATION 

2 

3 

U 

5 

6 

7 

8 

9 

12 

lU 

16 

Total 

DISTRIBUTION OF . 

NUMBER 

STATIONS 

12 

27 

36 

U 

26 

1 

7 

3 

2 

1 

3 

122 

SERVICE STATION PUMPS *' 

TOTAL NUMBER 

FJMPS 

2U 

81 

1UU 

20 

156 

7 

$6 

27 

2U 

lU 

U8 

601 

PER CENT 

OF STATIONS 

9.3 

22.2 

29.5 

3.3 

21.3 

0.8 

5.7 

2.5 

1.6 

0.8 

2.5 

100.0 

a)From field survey of 122 stations. 

-36-
TABLE XII 

DISTRIBUTION OF SERVICE STATIONS BY COMPANY

 a ) 

BRAND NAME 

Standard 

Richfield 

Union 

Shell 

General Petroleum 

Texas 

Signal 

Wilshire 

Hancock 

Tidewater 

Independent 

Total 

a) From replies by 12 

Bulk Plant Facilities 

NUMBER STATIONS 

"'li staticns 

15 

19 

20 

11 

17 

13 

7 

U 

2 

5 

ll 

12U 

to r.ail survey. 

PER CENT 

OF TOTAL 

12.1 

15.3 

16.2 

8.9 

13.7 

10.5 

5.6 

3.2 

1.6 

U.O 

8.9 

100.0 

When considering the effectiveness of vapor return systems on 

tank trucks, the bulk loading facilities where the tank trucks are filled 

must be taken into account. Rule 61, which controls gasoline loading 

into tank trucks and trailers, states in part that "this rule shall not 

apply to loading of gasoline into tank trucks and trailers from any loading facility from which not more than 20,000 gallons of gasoline are 

loaded in any one day." Thus, the smaller bulk plants have no vapor 

recovery systems, and any truck containing vapors from a vapor return 

dump system would lose all these vapors to the atmosphere when being 

filled at the smaller facilities. Additional vapor formation by volatilization of the gasoline during loading, is minimized in almost all cases by 

use of a dip tube for the filling of the tank trucks. 

•37-
P.43 

As can be seen from Table XIII, all but 6 per cent of the gasoline 

in Los Angeles County is loaded at the refinery or at the large bulk 

terminals. This leaves only 11,900,000 gallons per month loaded at 

facilities not currently provided with means for controlling the vapors. 

TABLE XIII 

BULK GASOLINE LOADING IN LOS ANGELES COUNTY a) 

CLASS 

Major Refinery 

or Bulk Terminal 

Independent 

Refinery 

Small Bulk 

Distribution 

Plant b) 

Total 

NUMBER OF 

INSTALLATIONS 

22 

5 

71 

98 

THROUGHPUT 

(gal/month) 

166,100,100 

1U,000,000 

11,900,000 

192,000,000 

% TOTAL 

(vol % of total) 

87 

7 

6 

100 

a) Projected to 1962 total throughput of 192,000,000 gallons per month 

from earlier data. Aircraft fueling facility throughput figures were 

eliminated for the 1962 projection. 

b) Each facility handles less than 20,000 gallons per day. 

At the larger bulk plants, where a vapor recovery system is in 

operation, the only appreciable losses would occur when the hatch 

covers were opened for filling. These losses would be equal to the volume change occurring when the pressure built up by volatilization of the 

residual gasoline in the tank truck was suddenly released to atmosphere, 

In most instances, the hatch covers do not make a perfectly effective 

pressure seal, so by the time the truck returns to the loading rack the 

pressure is almost atmospheric. The pressure buildup may, however, 

•38-
P.44 

vary from atmospheric to approximately 3 pounds per square inch, as 

determined by the setting of the spring loaded relief valve bqilt into the 

dome cover. 

Tank Truck Facilities 

According to a compilation made in 1956, there were at that time, 

about 1500 tank trucks being used for hauling gasoline in Los Angeles 

County (4). Assuming that the number of trucks has increased in proportion to the increase in gasoline sales, an estimate of 1700 tank trucks 

was used in making the cost estimates discussed in Section VII. 

It was estimated that about 50 Der cent of the hauling vehicles were 

semi-trucks with 5 compartments each, and the other 50 per cent were 

trailer-trucks with 6 compartments each. The compartment capacities 

varied from 1200 to 1300 gallons, and the majority of the trucks used a 

3-inch diameter hose as a discharge line from the compartments. Hauling operations of this type of vehicle were usually on an around-the-clock 

basis. 

The dome cap on each compartment was usually equipped with two 

spring loaded relief valves. One was a vacuum relief valve, factory-set 

to open at a pressure difference of 7 inches of water. In practice, however, the differential was somewhat lower. The second valve was a 

pressure relief valve, normally set to open at from 3 to 5 pounds per 

square inch pressure difference. 

-39-
P.45 

VII. COST ESTIMATES FOR VAPOR RETURN SYSTEM 

Service Station Costs 

In order to obtain cost appraisals for equipping facilities with a 

vapor recovery system, the Nishkian interlock vapor valve was taken 

as a typical installation. Estimates for equipping newly constructed and 

existing facilities with this valve were obtained from M. A. Nishkian 

and Company in a letter dated March 9, 1961, and are summarized in 

Table XIV. 

TABLE XIV 

ESTIMATED COSTS OF EQUIPPING CONSUMER FACILITIES WITH 

A GASOLINE RECOVERY SYSTEM 

FACILITY 

New Construction 

Service Station: 

Fill pipe diameter, 

3 inches or greater 

Fill pipe diameter, 

less than 3 inches 

Consumer Accounts

 a ' 

NUMBER TANKS 

No estimate 

22,800 

5,Uoo 

10,000 

COST/TANK 

(dollars) 

125 

600 

650 

650 

TOTAL COST 

(dollars) 

No estimate 

13,680,000 

3,510,000 

6,500,000 

$ 23,690,000 

a) Assumed all to be less than 1500 gallons capacity, with fill pipes 

less than 3 inches diameter. 

-41-
P.46 

The estimated cost of converting a typical retail station, with 3 

tanks, to a vapor recovery system would range between $1800 and $1950, 

depending upon the size of the existing fill pipes. In the case of stations 

where the existing fill pipes are 4 inches in diameter (internal pipe size), 

and in sound condition for cutting and rethreading, a cost of $600 per tank 

is estimated. This includes performance of all operations required to 

install the tank fill and vapor removal valve, the tank vent vapor check 

valve, and the tank fill box with traffic cover. 

The tanks that have fill pipes less than 3 inches in diameter would 

require the installation of a new 4-inch fill pipe to accommodate the 

Nishkian valve. The manufacturers quote an estimated cost of $650 per 

tank to replace an existing fill pipe with one of a required diameter, and 

to do all the necessary work described above. Probably all of the consumer account tanks, and approximately 19 per cent of the retail tanks, 

a total of 15, 400 tanks, would be in this category. 

Three alternatives are also possible to reduce the cost to the service station, but still provide a measure of vapor control. The first would 

be to install a modified vapor control system which would not require a 

vapor return valve such as the Nishkian unit. For this installation, a 

submerged fill tube and the existing vent pipe would be the only requirements. It would be necessary to excavate in order to make an underground connection between the vent line and the fill box where the vapor 

return hose connection would be located. Installation of such a system 

would be dependent on the condition of existing pipe and the size of fill 

pipes and vent lines. The average cost probably would be about $500 per 

tank, plus an unknown amount to equip the tank truck. 

A second, simpler, method is to employ the concentric hose arrangement developed by the APCD in 1955, and illustrated in Figure 10. 

Additional control equipment needed with this device consists of a dip 

tube for submerged filling, and a fitting on the fill pipe to accommodate 

the concentric hose. Total costs for this installation would average 

about $200 per tank, exclusive of the expense of equipping the tank 

trucks, detailed in a later section. 

The third alternative would be to utilize a submerged fill only, 

with no vapor return system. Using this method, vapor losses from 

filling operations would be 37 per cent less than the splash fill loss, a 

saving of about 1 gallon of gasoline for each 1000 gallons delivered. 

Although this saving is small dollar-wise, it would accrue to the station 

operator, since the material would not volatilize and be lost, but would 

remain in the tank as liquid. The saving could be realized without the 

-42-
CO 

I 

Figure 10. Air Polluti 

on Control District 

vapor recovery system for 

service station storage tanks. 
installation and use of a vapor return valve, and thus the initial cost 

would be low. The only expenditure required would be the purchase and 

installation of a submerged fill tube in the existing fill pipe, and would 

amount to about $50 per tank. 

Bulk Plant Costs 

As previously stated, there are 71 small bulk distribution plants 

in the County, which handle 6 per cent of the total gasoline used. These 

would require some modifications to enable them to recover the vapors 

from the tank trucks by providing, for instance, a simple system of collecting the displaced vapors in the storage tank from which the liquid 

gasoline is being withdrawn. Modifications in this case would consist of 

some simple pipe work and adequate connector fittings to accommodate 

a vapor return hose from the manifold system which would be installed 

in the tank trucks. 

The estimated cost of outfitting each small bulk plant is $500. This 

estimate is based on the assumption that each sm?ll plant has an average 

of 2 tanks dispensing gasoline, and that 200 feet of 2-inch pipe installed 

with the necessary fittings would be required for each plant. Thus a total 

of $35, 500 would be needed to equip all 71 of the small bulk plants with 

displacement vapor recovery systems. 

As mentioned before, all of the larger bulk loading facilities now 

have vapor control systems of one type or another. These systems adequately take care of the vapors returnee to the bulk plant in the tank 

trucks, and no additional expenditures are necessary. 

Tank Truck Costs 

At the time of the earlier studies made by the APCD in connection 

with the concentric hose system, an estimate of S350 per truck plus 

S150 per compartment was given for equipping a tank truck with that 

particular system. The recovery system under study employs separate 

gasoline fill and vapor return hoses, rather than a single concentric 

hose. However, because current cost estimates could not be obtained 

for this study, the values for the single concentric hose were used. 

This assumption was justified on the basis of the fact th:.t, although construction costs are currently higher than at the time of that study, the 

separate vapor return hose used in the present device would be less 

costly than the earlier complex concentric hose. Thus, the resulting 

•44 -
P.49 

net cost probably would be approximately the same. 

With these assumptions, the cost of equipping the 1700 tank trucks 

(the number estimated in the previous section) for the recovery of vapors 

using a separate vapor return hose system would be: 

850 semi-trucks with 5 compartments each $ 935,000 

850 trailer trucks with 6 compartments each $1,062, 500 

$1,997,500 

This separate hose equipment for the trucks would consist of a vapor 

return hose, a manifold system and the necessary fittings, plus labor. 

-45-
P.50 

Vni. EVALUATION OF NISHKIAN VALVE 

Description 

The interlock valve used in the tests was supplied by M. A. 

Nishkian and Company, 3755 Long Beach Boulevard, Long Beach, California. The intended usage of this valve is as a permanent installation 

on the fill pipes of underground gasoline storage tanks at service stations. It would provide a means whereby the gasoline vapors displaced 

from the underground tank during the refilling operation could be re -

turned to the tank truck to fill the space vacated by the liquid gasoline. 

It should be noted at the outset that the valve itself is only one part 

of an over-all vapor recovery system. The entire system would consist 

of the valve, or some other tight-fit connection to the underground tank, 

a vapor return hose between the tank and the tank truck, and valves and 

piping to each gasoline compartment of the tank truck. 

As submitted, the Nishkian valve assembly consisted of the valve 

body and a submerged fill tube, as illustrated in Figure 11. The 4-inch 

coupling with the attached 1/4-inch static pressure probe was fabricated 

by District testing personnel for use in the current test program. This 

was used as a connecting link between the valve and the fill pipe, and 

also as a means for obtaining the static pressure in the underground tank 

during filling operations. The main features of the valve are a crossarm connecting tube through which the gasoline vapors pass from the 

underground tank to the vapor return line, and an interlock arrangement 

that prevents the flow of gasoline to the underground tank unless the 

vapor return hose is connected to the valve. 

Not included as an integral part of the valve, but intended for use 

with the 4-inch fill pipe of the test facilities, was a 3-inch dip tube or 

submerged fill pipe. A dip tube of 2-1/2 inches could be used without 

restricting the flow of gasoline or vapors unduly, but anything smaller 

than this would be unsuitable. Thus, the valve could be adapted for use 

on tanks with a 3-inch fill pipe, but, as previously mentioned, tanks 

whose fill pipes are smaller than this would require further modification. 

-47-
P.51 

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•48-
P.52 

Installation of the valve on an underground tank is shown in Figure 

12, while Figure 13 illustrates the valve in use during an actual filling 

operation. The 4-inch pipe assembly located to the left of the gasoline 

fill hose and between the valve body and vapor return hose is a viscous 

flowmeter assembly for measuring the vapor flow rate during the testing 

operations. 

Operation 

As stated above, the main function of the Nishkian valve is to provide a means whereby the vapors from the underground tanks can be 

transferred to the tank truck during filling operations for the underground 

tanks. These vapors would then be returned to a collection system at a 

bulk plant, thereby providing an over-all plan for control. In order to 

test the efficiency of the valve as part of this procedure, it was necessary 

to conduct a series of tests with and without it as a component of the filling equipment. Data obtained from these tests, along with data already . 

available in the District's files, were then used to make this evaluation. 

In the function for which the valve was designed, performance was 

quite satisfactory. No major obstacles or difficulties were encountered 

which would make the filling system impractical from an operational 

viewpoint. The tests did, however, disclose two problems, not related 

to the Nishkian valve itself, which should be remedied in the design of 

a complete vapor recovery system: (1) vacuum build-up in the tank 

truck compartments, and (2) difficulty in draining gasoline from the 

delivery hose after the flow has stopped. 

No specifications were obtainable for the maximum allowable 

vacuum in the tank truck compartments. Values observed in the current 

tests reached a maximum of 4 inches water column during normal delivery, with an increase to a maximum of 10 inches water column with the 

vapor return system in operation. Since the tanks of the tank trucks 

collapse rather easily, this vacuum is a critical factor, and limits 

should be accurately measured. Maximum allowable vacuum specifications could then be made, and the size of hose, valves, and fittings of 

the vapor recovery system could be designed so as to prevent any possible tank collapse. 

In one test, when using submerged filling with open vent conditions, 

some difficulty was encountered in draining all the gasoline from the fill 

hose after the flow had stopped. This resulted from the development of 

a pressure differential between the underground tank and the truck 

•49-
&&&» 

Figure 12. Nishkian return valve mounted on fill pipe. 

1. Valve body 

2. Aluminum tubing for actuating mechanical interlock system 

3. Gasoline filling hose 

U. Quick-connect coupling for hose to valve 

5« Bottom section of viscous flow meter and vapor return system 

6. Manometer used in study to measure pressure in underground tank 

during filling 

-50-
P.54 

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-51-
compartment sufficient to hold the liquid in the hose. In this particular 

instance, the truck driver "cracked" (partially opened, then closed 

again) the quick-connect coupling at the connection between the fill hose 

and the meter to allow air to enter. In general, this condition could 

probably be corrected by the use of a small air bleeder, or vacuum 

breaker valve, near the truck meter. This would permit air to enter 

the hose to equalize the pressure and thereby allow the hose to drain 

completely. 

Limitations 

From the results of the current investigation, it would seem that 

the only limitations to the use of the Nishkian valve as .part of a vapor 

return system would be those of installation. Since it is intended to be 

part of the permanent equipment for the filling of the underground tanks, 

the valve should be installed so that it would not project above ground 

and thus restrict vehicle movement in the service station area. For 

new construction this would be easy to do, but in existing stations most 

of the tanks are not at a sufficient depth to permit this manner of installation. Therefore, it would be necessary either to deepen the location of 

the tanks (obviously requiring excavation and increasing the cost estimates previously mentioned), or to redesign the valve to a shorter size. 

A third alternative would be to attach the valve to the system only during 

the filling operations. However, this would be an inconvenience to the 

station personnel, and could well result in disregard of the device during 

the filling operation. ~—-

Incorporation of the valve as part of the tank truck equipment instead of the station facilities would be possible, but all connections would 

have to be standardized throughout the County. This procedure, too, 

would be less convenient, and could also lead to disregard of the use of 

the equipment. 

If a vapor return system, incorporating the Nishkian valve, were 

put into effect, it would necessitate the enaction of additional air pollution legislation. This could possibly consist of an amendment to Rule 61 

deleting the minimum size clause for the loading facilities, thereby extending the coverage to small bulk plants and all service stations. With 

the valve installed as recommended it would be a permanent part of the 

service station equipment. As such, enforcement of its use should not 

be difficult, and only an inspection of the initial installation should be 

required. 

•52 -
P.56 

i 

IX. REFERENCES 

1. Los Angeles County Air Pollution Control District. "Total Air 

Pollution Emitted and Prevented in Los Angeles County." 

(Los Angeles: Los Angeles County Air Pollution Control District, 

January 1962.) 

2. Los Angeles County Air Pollution Control District. Second Technical and Administrative Report on Air Pollution Control in 

Los Angeles Countv. 1950-1951. (Los Angeles: Los Angeles County 

Air Pollution Control District, Q952 ?].) 

3. Beckman, Arnold 0.; Haagen-Smit, A. J.; Kaplan, Joseph; Brantley, 

L. Reed; Poole, John W. Report of Special Committee on Air Pollution. (Report made to Governor Goodwin J. Knight's Air Pollution 

Control Conference, December 5, 1953.) 

4. Western Oil and Gas Association. Cost Survey. (A Report Prepared by the Marketing Subcommittee of the Air Pollution Control 

CommitteeH (Los Angeles: Western Oil and Gas Association, 

August 1956.) 

•53-
P.57 

*y°su% 

flSTtt Ji~B-o! 

UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

ANN ARBOR. MICHIGAN 48105 

JUL I 3 I98T 

OFFICE OF 

AIR AND RADIATION 

MEMORANDUM 

SUBJECT: 

FROM: 

TO: 

Inclusion of Benzene Gasoline Marketing Docket, 

A-84-07 into Onboard Docket, A-87-11 

Richard S. Wilcox, Environmental Scientis 

Standards Development and Support Branch 

Onboard Docket, A-87-11 

The Benzene Gasoline Marketing Docket, No. ^84-07, is 

being incorporated by reference into the Onboard Docket, No. 

A-87-11. The Benzene Gasoline Marketing Docket contains 

considerable background information and relevant data 

concerning the onboard vapor recovery requirement, in addition 

to references for the onboard draft regulatory support 

documents. For these reasons, its inclusion is appropriate. 
P.58 

A)-J 7-// 71-B -oo. 

^ 6 0 SU>. 

<r _ . ** 

iSE 

% PRO*'-' 

^ 

UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

A NN ARBOR. MICHIGA N 48105 

OFFICE OF 

AIR AND RADIATION 

DEC I 7 1986 

MEMORANDUM 

SUBJECT: 

FROM: 

TO: 

THRU: 

Refueling Configuration Criteria 

Robert J. Johnson, Environmental Protection Spec. 

Standards Development and Support Branch 

The Public Record 

Glenn W. passavant, Project Manager • • 

Standards Development and Support Branch 

A /sv 

Chester J. France, rhi pff ^ y//3S t 

Standards Development a^nd Slipppf^t Branch 

,s? v ^ .yi 

Thomas M. Bali, Chief -<^_ ^ . V / / A>n. 

Certification 3ranch /^ ~ 

The refueling proposal provides criteria to be used 

determining refueling 

certification purposes 

§86.090-24 of the 

Family/control system 

manufacturer's product 

similar basic design 

for 

systems for 

contained in 

regulations. 

to divide a 

vehicles with 

families and control 

These criteria are 

proposed refueling 

criteria are used 

line into groupings of 

and deterioration characteristics foe 

purposes of emission control durability demonstration. Within 

each family/system combination, the normal certification 

practice is to then select emission data vehicles for 

compliance testing. These emission data vehicles are selected 

based on configuration criteria which identify the v/orst-case 

emitters in that family/system combination. 

Official configuration criteria for selecting emission 

data vehicles will ultimately be developed using the normal 

Advisory Circular process. However, during the course of the 

analysis used to develop the proposed refueling family/system 

determinants, criteria were also identified that could be used 

to select emission . data vehicles within a given family/system 

combination. These are attached to inform commenters about 

EPA's preliminary ideas regarding refueling configuration 

criteria and also to provide additional information to complete 

the context within which 

family/system criteria. 

commenters can evaluate the proposed 
P.59 

Possible Refueling Configuration Criteria 

Refueling configuration criteria would be used to select 

emission data test vehicles within a given refueling family/ 

control system combination. Application of the deterioration 

factor calculated for the family/system combination to the 

emission data test results determines whether the family/system 

combination is in compliance with the standard, so emission 

data vehicles normally represent the highest emitters within 

that combination. Possible configuration criteria for 

refueling emission data vehicle selection are listed below: 

1. Fuel system type and return line usage determines 

the amount of fuel recirculated to the vehicle tank, which in 

turn affects the temperature of the tank fuel and has a direct 

effect on refueling emissions. All fuel-injected vehicles have 

return lines that recirculate unused fuel to the tank. Some 

carbureted vehicles also have lines that nominally return 

gasoline vapor to the tank to prevent vapor lock. These vapor 

return lines may also return some liquid fuel to the tank, 

although not as much as would be returned in a fuel-injected 

system. Fuel returned to the tank is heated by the compression 

associated with the pumping process as well as by exposure to 

engine compartment heat and, in some cases, exhaust system 

heat. This heated fuel in turn warms the residual fuel in the 

vehicle tank. Since refueling emissions vary inversely with 

the difference between tank fuel temperature and dispensed fuel 

temperature (known as AT), warming caused by returned fuel 

affects the quantity of refueling emissions generated. In 

general, warmer tank fuel results in decreased refueling 

emissions for a given dispensed fuel temperature. 

The amount of returned fuel varies with the type of fuel 

metering, and a hierarchy of fuel volumes can be established. 

High pressure fuel injected systems normally return more fuel 

to the tank than do low pressure systems. Fuel injected 

vehicles normally return more fuel than do carbureted systems 

with return lines. Thus, given identical refueling control 

systems (i.e., tank size, canister size, etc.), a carbureted 

vehicle without a return line could be expected to exhibit the 

highest refueling emissions, while a high-pressure fuel 

injected version could be expected to exhibit the lowest 

emissions. 

2. Fuel tank size, configuration and material also can 

be used to select an emission data vehicle within a given 

family/system combination, since for vehicles with identical 

control systems, the vehicle with the largest tank size would 

obviously represent the worst-case configuration. Tank 

configuration, i.e., shape, fillpipe configuration and internal 

baffling, has also been shown to affect refueling emissions. 

Baffling can break up the natural liquid and vapor flow 

patterns inside the tank and the shape of the tank and fill-
P.60 

- 2-

pipe configuration can affect the amount of fuel splashing (and 

droplet entrainment) during a refueling operation. Tank 

material affects heat transfer and, consequently, heat 

dissipation during vehicle operation. All of these factors 

could therefore have an effect on the amount of refueling 

emissions, and should be considered as configuration criteria. 

3. Canister location can affect adsorption and 

desorption of refueling vapors due to the variation in 

operating temperatures associated with different locations. 

Although most if not all evaporative canisters are located in 

the engine compartment, large refueling canisters may pose some 

packaging problems which could result in their being located 

under the body or in some other location. Location away from 

engine compartment heat produces different canister adsorption 

and desorption characteristics. The effect of heat on canister 

operation is to promote desorption and to inhibit adsorption, 

so that identical canisters could have different loading and 

purging characteristics, depending on where they were located. 

Engineering judgment would be required to select a worst-case 

vehicle for emission data testing. 

4. Canister housing material could affect heat transfer 

and consequently canister operating temperatures. Tests have 

shown that canisters undergo a rapid internal temperature rise 

during a refueling operation, which might vary somewhat 

depending on the heat dissipated through the canister body. 

Different body materials would have different rates of heat 

dissipation, which could affect loading and purging 

characteristics. For example, a body with a high rate of heat 

transfer could run cooler than one with a lower rate of heat 

transfer, allowing the charcoal to adsorb a larger quantity of 

vapor than would be adsorbed at a higher operating 

temperature. Canister body material should therefore also be a 

configuration criterion. 
P.61 

' A. \ 

ft-v-a JT-Q-A 

UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

WASHINGTON, D.C 20460 

MEMORANDUM 

JUN I 2 1987 

OFFICE OF 

GENERAL COUNSEL 

SUBJECT: 

FROM: 

THRU: 

Respons e t o Claim tha t EPA i s Legall y Require d 

t o Impoi?e Stag e I I Gasolin e Controls i n Al l 

Ozone Nonattainmen t Area s 

Ralph J. Collel i Jr.fv. v . 

Richar d B. Ossias, Attorney s 

A ir and Radiatio n Qivisio h (LE-132A) 

rJU fr 

T O: 

Alan W. Eckert 

Associat e GeneraT-'Cduhsel 

Air and Radiation Division (LE-132A) 

Docket No. A-87-11 

:#3f^ 

Background i 

This memorandum evaluates certain legal arguments made 

to EPA by Multinational Business Services, Inc. ("MBS") in 

response to EPA's draft study entitled "Evaluation of Regulatory Strategies for Gasoline Marketing". See 49 Fed. Reg. 

31706 (August 8, 1984). In essence, that study (and EPA's 

current decisionmaking effort regarding gasoline marketing) 

concerns whether control of gasoline vapors released during 

motor vehicle refueling is appropriate and, if so, whether 

control at the pumps ("Stage II" controls) or on the vehicles 

("onboard controls") are desirable. The hydrocarbon compounds 

in gasoline vapor contribute to ozone formation in the atmosphere, 

while benzene and other constitutents of the vapors pose 

risks of cancer. 

Under Section 202(a)(6) of the Clean Air Act, the 

Administrator of EPA is directed to determine the^" feasibility 

and desirability" of requiring onboard controls which would 

avoid the necessity for Stage II controls. \J That provision 

also directs the Administrator, when makirtg that determination, 

4F/ ; ;^:!^M^^^# ^ &^jytA& 

1/ EPA initially complied with this direction in 1981 when 

it decided, at that time, not to require onboard controli 

46 Fed. Reg. 21628-21629 (April 13, 1981). 
P.62 

-2-

to compare the costs and effectiveness of onboard to those of 

Stage II, taking into account such other factors as fuel 

economy, administrative burdens, and.equitable distribution 

of costs. If the Administrator determines that onboard 

controls are "feasible and desirable," then he must require 

such controls by regulation. 

MBS argues, however, that the Administrator has no 

choice but to require Stage II controls by regulation now for 

all nonattainment areas.and, thus, as a practical matter, no 

discretion to reguire onboard controls as an alternative. 

This claim, in brief, is based on the assumption that Stage 

II controls are required by section 172 of the Act to-be 

included as a "reasonably available control measure" (RACM) 

in the ozone SIPs for all nonattainment areas granted extensions 

of the target date for attainment until December 31, 1987. 2/ 

We do not agree with this argument. In particular, we 

do not believe that EPA is required to designate Stage II as 

RACM. Rather, we believe that Congress intended EPA to make 

a careful, reasoned decision, on the merits, as to whether 

onboard or Stage II controls should be imposed. 

Discussion 

Section 172(b)(2) of the Act requires that all 

nonattainment area SIPs provide for implementation of all 

"reasonably available control measures as expeditiously as 

practicable" to ensure attainment of each primary NAAQS by 

December 31, 1982, or, in the case of the ozone and CO standards 

in certain areas, by December 31, 1987. Nothing in the 

statute or EPA implementing regulations expressly defines the 

term "reasonably available control measure" for purposes of 

section 172. Thus, EPA has substantial discretion to determine 

whether and under what circumstances any particular control 

technology should be considered "reasonably available." 3_/ 

I 

' i 

2_l If this claim were correct, it could alter EPA's analysis 

of the relative costs and cost-effectiveness of Stage II 

and onboard controls'^ince additional investments in Stage II 

equipment, and capture of some refueliftg emissions* by Stage 

II controls, would have begun in many nonattainment areas 

before onboard controls could be implemented. At present, 

Stage II has been (or is being) installed only in Washington, 

D.C., certain areas in California, and the St. Louis, Missouri, A 

area. '"* 

3/ Section 108(f) of the Act requires EPA to publish, from • AA& 

time to time, information on methods to control various 

sources of transportation- or mobile source-related pollutants, 

(footnote continued) 
,£,63 

-3-

Cf. Chevron U.S.A. , Inc. v. NRDC, .467 U.S. 837 (1984). 

However, MBS argues, in part,' that Stage II now must be 

considered RACM because Congress implicitly assumed Stage II 

was RACM in 1977 when enacting section 172 and various vapor 

recovery provisions in the Act. Specifically, MBS suggests 

that section 202(a)(5) (authorizing EPA to prescribe vehicle 

fill pipe standards to ensure effective connection between 

fill pipes and any Stage II vapor controls)- and sections 323 

and 325 (providing certain exemptions from any federal Stage 

II requirements and determining which persons must bear Stage 

II costs) imply such a Congressional presumption. 

We do not agree that these statutory provisions indicate 

that Congress intended EPA to declare Stage II to be RACM in 

all nonattainment areas. First, the statutory provisions in 

question corae into play only jLf EPA first requires Stage II by 

regulation, and those provisions clearly do not require EPA 

to take that step. 4/ Second, the argument that Stage II 

must be considered RACM is inconsistent with the clear purpose 

of section 202(a)(6), which was also e.dded to the Act in 

1977. As stated earlier, section 202(a)(6) requires EPA to 

consider the feasibility and desirability of onboard controls 

"which would avoid the necessity of" Stage II vapor controls. 

The statutory language (and the legislative history of that 

section) clearly indicates that Congress intended EPA to 

consider onboard as at least a partial alternative 5/ to 

Footnote 3/ Continued 

including vapor emissions from fueling tranfers. 42 U.S.C. 

7408(f)(1)(A)(ii). EPA did publish such information on 

Stage II emission controls in 1978. "Hydrocarbon Control 

Strategies for Gasoline Marketing," EPA-450/3-78-017, April 

1978). However, neither section 108(f) nor EPA's information 

document states that Stage II controls must be considered RACM 

in all nonattainment areas. Of course, any State may conclude 

on its own initiative that Stage II is an appropriate measure 

for attainment of the ozone standard and incorporate such a 

requirement in a SIP. In fact, as discussed earlier in this 

notice, several states have incorporated such provisions and 

at least two other states have committed to do SJ*» 

4/ Section 202(a)(5) isvexplicitly, and sections 323 and 

325 are inherently, contingent on EFA' first deciding 

whether to require Stage II by regulation. "Thus, although 

Congress in 1977 may have ^thought it likely that EPA would 

require Stage II, it also anticipated that EPA might not do 

so and, as discussed later, clearly intended EPA to consider 

onboard as an alternative to imposing Stage II. 

5/ The legislative history of section 202(a)(6) indicates 

that Congress intended EPA to consider onboard controls, 

as a means to at least minimize, if not completely eliminate, 

irim-iamH^Ui 
P.64 

- -4 -

Stage II, largely because of Congress' concerns about the 

costs, cost-effectiveness and equity of Stage II controls. 

See, e_^g. , H.R. Rep. No. 95-294, 95th Cong., 1st Sess. 24 

Tcriteria for evaluating onboard), 299-300 (concerning costs 

and fairness of Stage II. controls). In fact, section 202(a)(6) 

specifically requires EPA to compare Stage II and onboard 

with respect to those factors. Moreover, by authorizing EPA 

to impose onboard controls only if the Administrator found 

them "desirable", Congress certainly intended EPA to have 

broad discretion in choosing between onboard and Stage II. 

Thus, EPA is entitled to consider all relevant factors in 

deciding whether onboard is a desirable alternative to Stage 

II, including issues (e.g., cancer risks due to vapors) that 

are not necessarily related to whether Stage II is RACM 

for ozone attainment purposes. 6_/ 

This broad mandate could not-be effectively carried, out if, 

as MBS has suggested, EPA were required to declare Stage II to 

be RACM. If Stage II were now required to be incorporated in 

the SIP of every ozone nonattainment area prior to December 31, 

1987, and implemented expeditiously under section 172, onboard 

(which cannot achieve its full potential for emission reduction as soon as Stage II could) could not, as a practical 

matter, "avoid the necessity" of Stage II. Moreover, onboard 

might not be a viable, cost-effective alternative in such a | 

case, given the resources that would have already been invested 

in Stage II. Thus, MBS' argument, in effect, would render 

section 202(a)(6) a nullity. Since every statute should be 

interpreted whenever possible to give full effect to all its 

provisions, and not to render any provision superfluous, 

Norfolk & Western Ry. Co. v. United States, 768 F.2d 373 (D.C. 

Cir. 1985), we do not believe that Congress would have 

intended such a result. Thus, we conclude that the Clean Air 

Act does not compel EPA to require Stage II as RACM in all 

nonattainment areas. 

Our conclusion is not changed by the fact that section 

172 sets December 31, 1987 as the target date for ozone attainment. It does not follow from the existence of that date 

that EPA is precluded from thoroughly considering Stage II 

and onboard under section 202(a)(6) and choosing the more 

"desirable" technology. Nothing in section 202(a)(6), or any 

6_/ As stated above, 

in 1981 not to require 

see n. 1 supra, EPA published a decision 

onboard control*. However, that 

earlier decision does not diminish EPA's authority to reevaluate 

this issue under the criteria and purposes of section 202(a)(6) 

d 

in light of changed and 

American Airlines, Inc. 

(en banc), cert, denied 

to reexamine and adjust 

of experience). 

current circumstances. See, e. g., 

v. CAB, 359 F.2d 624, 633~TD.C. Cir.) 

385 U.S. 843 (1966) (agency obliged 

prior regulatory decisions in light 

&3-

•:<£ 

. ...••i::.^,.xi.„c;-;.. .•.-,.._.,••. -L^ ^ 

• ••••:'i^>,-'.-..l-

:i-'«-feiJWg 
P.65 

-

5 -

other statutory provision, requires that the Administrator 

base his decision on whether to require Stage II or onboard 

solely or primarily on which technology can achieve greater 

progress toward attaining the'standard by December 1987. l_l 

Nor does anything in the Act reguire that he ignore or sacrifice 

the potential long-terra benefits from onboard controls in 

favor of the somewhat greater short-terra ozone reductions 

that Stage II potentially might produce. 8_/ Thus, although 

EPA should consider the need for States to impose additional 

measures to attain the ozone standard by the statutory deadline, 

that is only one factor in the determination under section 

202(a)(6) as to waether onboard is the more desirable control 

method. The need for long-term VOC reductions and other 

health-related concerns, in addition to other relevant economic 

and policy concerns, may also be considered. 

Nor do we agree with MBS' argument that EPA must require 

Stage II as RACM because, purportedly, EPA has previously 

determined that Stage II is presumptively a reasonably available measure. Although some older EPA information and SIP 

policy documents show that Stage II was considered technologically feasible, EPA has never required that a State 

include Stage II as RACM in its ozone nonattainment SIP as a 

condition for SIP approval, or otherwise defined Stage II to 

be RACM in any SIP or other rulemaking. Moreover, even if 

those isolated earlier statements were read as indicating an 

EPA presumption that Stage II was RACM, j)/ those statements 

7/ Congress certainly was aware of both the 1982 and 1987 

ozone attainment dates when it enacted both sections 

172 and 202(a)(6) in 1977. Thus, if Congress had meant either 

date to control the Administrator's decision under section 

202(a)(6), it presumably would have said so. By contrast, 

Congress explicitly listed several factors (e.g., cost, cost 

effectiveness, equity, and safety) that the Administrator 

must consider under section 202(a)(6). 

8_/ Of course, even if EPA required all ozone nonattainment 

areas to impose Stage II as RACM, that in itself would 

not necessarily ensure that all (or any) of the Spates would 

attain the standard by December 31, 1987. 

v > -^ 

9_/ Of course, that purported presumption potentially could 

be rebutted by a State demonstrating to EPA that Stage 

II is not "reasonably available" in a given nonattainment 

area. (For example, the cost and cost-effectiveness of Stage 

II in a particular area might be considered unreasonable if EPA 

reguires onboard controls.) 

• ••--'••••-»»-•' J •'- 'irt L • |• gjjj"^• ••in^'i.-X'.a&Aiii^ii'-wv. . : .„,. .—a;^j^,A3L,.'J.-*^.-j-^i 
P.66 

* " 

depredate the current decisionmaking process. Thus, in light 

of all of the information on vapor recovery now available to 

EPA, it still would be appropriate for. EPA to reevaluate 

whether Stage II is, in fact, now reasonably available. See, 

e.g., American Trucking Ass'n v.. Atcheson, Topeka, & Santa Fe 

Ry., 387 U.S. 397, 416 (1967) (agencies are "neither required 

nor supposed to regulate the present and the future within 

the inflexible limits of yesterday"); International Harvester 

Co. v. Ruckelshaus, 478 F.2d 615, 632 (D.C. Cir. 1973). Such 

a reevaluation is especially appropriate in light of the 

discretion implicitly granted to EPA by section 172 to determine what is reasonably available, and the clear directive of 

section 202(a)(6) to consider onboard as an alternative to 

Stage II. 10/ Thus, EPA remains free to consider this issue, 

and to decide whether Stage II is RACM for any or all nonattainment areas, taking into account the impact that imposition of 

onboard controls would have on the overall reasonableness .of 

Stage II. 11/ 

Conclusion 

The legal arguments made by 

language, structure, or legislat 

Act. Moreover, the clear purpos 

require EPA to consider onboard 

alternative to Stage II. That s 

discretion to the Administrator 

controls are "desirable." In li 

EPA is not required at this time 

to be RACM and that the Administ 

requiring onboard controls. 

MBS are not supported by the 

ive history of the Clean Air 

e of section 202(a)(6) is to 

controls as at least a partial 

ection also grants broad 

to determine if onboard 

ght of this, we believe that 

to declare Stage II controls 

rator is free to consider 

10/ In fact, the argument that EPA previously determined 

Stage II to be RACM depends, in part, on a 1976 EPA 

guidance memorandum of which, MBS claims, Congress may have 

been aware when it enacted section 202(a)(6). However, since 

Congress clearly directed EPA to consider onboard as an 

alternative to Stage II, despite that prior guidarTce memorandum, 

it follows that EPA is not precluded by any purported prior 

RACM guidance from deciding whether onboard is a desirable 

alternative to Stage II. .* 

11/ For example, EPA might1 conclude that Stage II is not 

reasonable in all nonattainment areas, despite its shortterm benefits, given its relatively limited ability to bring 

ozone nonattainment areas into attainment in the short-term and 

that much of the investment in Stage II equipment would be 

wasted once onboard becomes fully effective. 

^•memdt. ;£«*?. *> ^ ir^'^.!$ijl£\ Illifn ff'hl'l ti*i >!!*•• •' 1 'ii»ii*Mfc—» m, itnr i M*i&im*timmit 

•r::..;is^^/&v7*' 
/^7-/r ar-s-o/ 

P.67 

JAN 2 9 I98T 

MEMORANDUM

 U 

SUBJECT: Updated Computer Outputs for Stage II and Onboard 

Analysis 

FROM: Glenn Passavant 

TO: Steve Shedd 

Attached is the revised fuel consumption model output 

which you requested in order to complete the update of the 

Stage II and onboard analysis. After your update is complete, 

we request that you provide us revised information for both 

Stage II and onboard refueling controls for inclusion in the 

NPRM. This note outlines the information needed for various 

control scenarios and also provides the necessary input for the 

computer models. 

Desired Output for Various Control Scenarios 

More specifically, we'd like to obtain the average annual 

VOC emission reduction, annualized costs (including 

enforcement), and cost effectiveness values for the control 

scenarios indicated below. Each of the following control 

scenarios should be evaluated using both 11.5 psi (12.6 psi 

nationwide annual average) and 9.0 psi (11.3 psi nationwide 

annual average) RVP certification and summer in-use fuels (The 

9.0 psi numbers reflect 5 months of RVP control.): 

1. Stage II - Nationwide with exemptions at 

10,000/50,000 gallons per months (gpm). 

2. Stage II - 61 non-attainment areas with exemptions 

at 10,000/50,000 gpm. 

3. Stage II - 61 non-attainment areas with exemptions 

at 2,000 gpm. 

4. Onboard (49-state) - nationwide 

5. Onboard (49-state) - 61 non-attainment areas 

In addition, for the Preamble we'd like to have the 

average total capital cost and annualized net cost (annual cost 

and recovery credit) for service stations to implement Stage II 

controls for the 10,000/50,000 gpm exemption level and the 

incremental cost effectiveness for service stations between 

2,000 and 10,000 gpm. 
P.68 

Finally, we'd like the information necessary to do the 

incremental cost effectiveness analysis with respect to the 

various benefits of Stage II and onboard refueling controls, as 

was done in the OMB briefing. To pinpoint this, we need the 

attainment areas emission reductions and the incidence 

reductions (all 3 categories) for the following scenarios: 1) 

nationwide onboard (49-state) controls, and 2) 61 

non-attainment area Stage II controls with exemptions at 

10,000/50,000 gpm. 

It is also important to note that these new values should 

be included in any revisions to the RIA and that the RVP 

control case results should be included in the RVP sensitivity 

section of the RIA. Also, please note that any reference to 

onboard controls in the RIA should reflect refueling emissions 

control only (i.e., onboard incremental to evap.). The 

following section will provide the necessary input needed for 

the Stage II and onboard computer models to obtain our desired 

output. 

Necessary Input for Computer Models 

Table 1, attached to this note, contains the onboard costs 

for both 9.0 psi and 11.5 psi RVP certification and summer 

in-use fuels. The first line of each table shows the full 

onboard cost for a system controlling both refueling and excess 

evaporative emissions. The second line shows the vehicle-based 

excess evaporative emission control costs and the final line 

gives the net refueling control cost, or onboard incremental to 

evaporative emission control cost, which should be used in this 

analysis. 

For further input, the nationwide annual average RVP for 

9.0 psi certification and summer in-use fuels is 11.3 psi. 

This nationwide annual average value considers fuel volatility 

levels controlled at 9.0 psi from May through September and at 

ASTM volatility limits for the remaining portion of. the year. 

The resulting average annual refueling emission factor is equal 

to 5.17 g/gal for 9.0 psi certification fuel. The nationwide 

annual average RVP and average annual refueling emission factor 

for 11.5 psi certification and summer in-use fuels will remain 

the same values of 12.6 psi and 5.87 g/gal, respectively. 

In addition, Table 2 (attached) contains the onboard 

refueling recovery credits for both 9.0 and 11.5 RVP 

certification and summer in-use fuels. The 9.0 RVP values have 

been revised due to the change in the refuelinq emission factor 

resulting from 5-month volatility control. 

This concludes the necessary input needed for the Stage II 

and onboard computer models to obtain the indicated output 

desired. We would also appreciate copies of the revised 

computer disks reflecting the changes in the programs. If you 

have any further questions, feel free to contact me at FTS 

374-8408. Thanks for your continued assistance. 
P.69 

Model 

Year 

1990 

1995 

2000+ 

Table 1 

9.0 RVP Certification 

Cost 

Category 

Onboard 

Exc Evap 

Net 

Onboard 

Exc Evap 

Net 

Onboard 

Exc Evap 

Net 

LDV 

$19.20 

$- .90 

18.30 

$16.80 

$- .10 

16.70 

$15.40 

$- .10 

$15.30 

and Summer 

LDT 

Single 

$21.10 

$-1.10 

20.00 

$18.40 

$- .10 

18.30 

$16.90 

$- .10 

$16.80 

In-Use Fuel 

LDT 

Dual 

$44.40 

$-1.10 

43.30 

$40.50 

$- .10 

40.40 

$38.30 

$- .10 

$38.20 

s 

HDGV 

$32.20 

$-2.35 

29.85 

$28.80 

$- .20 

28.60 

$28.40 

$- .20 

$28.20 

11.5 RVP Certification and Summer In-Use Fuels 

Model 

Year 

1990 

1995 

2000+ 

Cost 

Category 

Onboard 

Exc Evap 

Net 

Onboard 

Exc Evap 

Net 

Onboard 

Exc Evap 

Net 

LDV 

$20.00 

$-2.90 

$17.10 

$17.70 

$-2.00 

$15.70 

$16.30 

$-2.00 

$14.30 

LDT 

Single 

$22.20 

$-3.80 

$18.40 

$19.60 

$-2.60 

$17.00 

$18.10 

$-2.60 

$15.50 

LDT 

Dual 

$46.60 

$-3.80 

$42.80 

$42.70 

$-2.60 

$40.10 

$40.50 

$-2.60 

$37.90 _ 

HDGV 

$34.30 

$-4.20 

$30.10 

$30.60 

$-3.50 

$27.10 

$30.20 

$-3.50 

- $26.70 
P.70 

Table 2 

Onboard Refueling Recovery Credits 

9.0 RVP Certification and Summer In-Use Fuels (5 months) 

Model year LDV 

1990 5.3 

1995 4.9 

2000 4.4 

2010 4.0 

(x 10"b gallons 

LDT Single 

6.8 

6.6 

6.1 

5.4 

per mile) 

LDT Dual 

2.9 

2.8 

2.6 

2.3 

11.5 RVP Certification and Summer InModel year. LDV 

1990 6.6 

1995 6.0 

2000 5.5 

2010 5.0 

(x IO"* gallons 

LDT Single 

8.6 

8.3 

7.6 

6.9 

per mile) 

LDT Dual 

4.4 

4.2 

3.9 

3.6 

HDGV 

18 

17 

17 

15 

-Use Fuels 

HDGV 

21 

20 

19 

18 
P.71 

i" £%\ UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

| ^V|^Z J? ANN ARBOR. MICHIGAN 48105 

3£~fcoS 

JUL I 7 I987 OFFICE OF 

AIR ANO RADIATION 

MEMORANDUM 

SUBJECT: Analysis of M&D Effects on Refueling Emissions 

FROM: 

TO: 

Robert B. Hawkins, Mechanical Engineering Technician 

Standards Development and Support Branch %UST tf%%*d&»a_ 

The Record 

THRU: Glenn W. Passavant, sr. Project Manager SMSAOHcJ/^i*«^»*>7 

Standards Development and Support Branch 

Chester J. France, chief 

Standards Development and Support// 

Introduction 

Attached are the results of the calculations used to 

estimate the potential malmaintenance and defects (M&D) effects 

for onboard control of refueling emissions. The information 

used in this analysis was taken from EPA's emission factors 

data base for evaporative emissions of 163 fuel injected 

vehicles. The individual data presented here are only for 

those vehicles which might be considered problem vehicles under 

the onboard scenario. Even though 163 FI vehicles were tested 

only 158 total vehicles were used here. Five of the problem 

vehicles had problems which would affect evaporative but not 

refueling emissions (i.e. gas cap leaks, air cleaner 

problems). Rather than include these vehicles as problem free 

for refueling purposes and using the average problem free 

vehicle emission rate, they were simply dropped from the data 

set. Problem vehicles in this analysis J-^-.J 

non-tampered vehicles whose emission control 

are defined as 

devices are not 

on visual 

results are- from using 

at 9.0 RVP fuel. The 

a*. ~*. v.^ e^~~^^... vehicles was approximately 

for problem-free vehicles the average mileage was 

of the volatility NPRM RIA. Emission 

9.0 RVP fuel on vehicles certified 

average mileage of all problem 

60,000 miles; 

about 35,000. 
P.72 

Explanation of Tables and Overview of Exhibits & Methods 

Table 1 shows four types of problem vehicles groups and 

related information. The information pertains to vehicle 

problems, vehicles numbers, test fuel RVP, hot soak, diurnal, 

and average combined emissions, and individual vehicle mileages. 

Table 2 gives the overall results of tests for the fleet 

of cars used for comparison and analysis. This table gives the 

summary information on the 158 fuel-injected cars. 

Table 3 shows emission results on three vehicles which 

were considered problem vehicles in the emissions factor 

program but passed the standard when tested on 9 RVP fuel. 

These vehicles were not considered to be problem vehicles in 

this analysis, but would be in an analysis where 11.5 RVP test 

fuel was used such as in Table 6-B-l in the volatility NPRM RIA. 

Exhibits I and II show the two methods that were used to 

calculate the effects of M&D on onboard efficiency. The first 

method (Exhibit I) shows how the M&D effects related to onboard 

controls would increase fleet average controlled refueling 

emissions. The analysis is done with and without the saturated 

canister problem vehicles, since the liquid/vapor separator in 

the onboard system could eliminate the saturated canister 

problem, if the problem were due to liquid in the canister. 

Depending on whether 9 or 11 vehicles were used, the onboard 

efficiency in use decreases between 0.7 and 0.9 percent. 

Exhibit II calculates the effect of M&D on refueling 

emission control by estimating the loss of efficiency relative 

to uncontrolled evaporative emissions for a FI vehicle (21g) 

for the problem vehicles and then fleet weighting the effect. 

This method is also shown for 9 and 11 vehicles for the reason 

discussed above. Using this approch, M&D would increase 

refueling emissions between 2.1 and 2.4 percent. 

In conclusion the attached sheets give a detailed and 

systematic analysis of the effects of M&D on onboard refueling 

controls, and show that using either approach the impact is 

small. 

Attachments 
P.73 

Table 1 

Vehicle/Emission Data 

Avg. Combined Vehicle Average 

Problem Veh ft RVP H S p_I Diurnal & Hot Soak Mileage Mileage 

Purge System 6006 9.0 2.32 2.85 28,970 

6011 9.0 1.19 2.84 22,410 

6018 9.0 8.16 6.31 7.89 36,580 

Purge Hose 

Disabled 6021 9.0 13.48 2.65 16.13 85,760 

Plugged 

Duty/Filter 5082 9.0 10.47 1.00 47,000 

5135 9.0 0.86 3.04 60,870 

5224 9.0 2.89 11.51 10.50 97,810 

5264 9.0 0.13 12.08 60,350 

Canister 

Damaged 4427 9.0 1.67 0.98 2.65 90,990 58,971 

Tot of 9 Vehicles 530,740 

Saturated 

Canister 4171 9.0 2.14 3.38 56190 

5277 9.0 1.10 10.24 8.43 59830 58,796 

Tot of 11 Vehicles 646,760 
P.74 

Table 2 

Summary of Vehicle Evap. Emission Data 

Problem-Free 

Problem Vehicles 

(Incl sat can) 

Vehicles 

with 

Diurnal 

Problems 

147 

9 

11 

Vehicles 

with 

Hot Soak 

Problems 

147 

9 

11 

Ver dele 

(grams/test) 

Average 

Diurnal 

1.17 

4.81 

5.17 

Emissions 

Hot Soak 

0.68 

4.57 

4.04 

Vehicle 

(Diurnal Hot Soak) 

Combined Avg 

1.85 

9.38 

9.21 

Average 

Emissions 158 158 1.45 .87 2.32 

of all Vehicles* 

Even though 163 FI vehicles were tested only 158 total vehicles were used 

here. Five of the problem vehicles had problems which would affect 

evaporative but not refueling emissions (i.e., gas cap leaks, air cleaner 

problems). 
P.75 

Table 3 

"Problem Vehicles" Which Passed Evap Standard Using 9.0 RVP Fuel* 

Category Veh # RVP H S DI Total Mileage 

Plugged Dirty/Filter 5080 9.0 0.34 0.43 0.77 550 

5132 9.0 0.50 1.34 1.84 9200 

6007 9.0 1.07 0.89 1.96 25920 

Counted as problem free in this analysis. 
P.76 

Exhibit I 

M&D Effects on Onboard Efficiency Based 

on Increases in Controlled Emission Rates 

3(7.89)+1(16.13)+4(10.5)+1(2.65)+3(1.52)+144(1.8) = 2.23g 

156 

2•23g all (problem and problem free vehicle emissions) 

1.79g problem-free vehicle emissions 

=24.4% increase over problem-free vehicle emissions 

Refueling Emissions 5.9g/gal(1-0.97)=0.177 g/gal 

after Control (refueling problem-free emission rate) 

(.177g/gal)(1.244)=.220g/gal 

(refueling emission rate with problem 

vehicles) 

Efficiency: l-(.220)= .963=96.3% 

(5.9) 

Thus efficiency changes to 96.3% from 97% 
P.77 

Exhibit I. 

Continued 

(Includes Saturated Canister Vehicles) 

3(7.89)+l(16.13)+4(10.5)+l(2.65)+2(8.43)+3(1.52)+144(1.8)= 2.31g 

158 

2,31g all (problem and problem-free vehicle emissions) 

1.79g problem-free vehicle emissions 

=29.0% increase over problem-free vehicle emissions 

Refueling Emissions 5.9g/gal (1-0.97)=o.I77g/gal (refueling 

after Control problem-free emission rate) 

(.I77g/gal)(1.29)=.228g/gal refueling emission 

rate with problems 

Efficiency: l-(.228)= .961=96.1% 

(5.9) 

The efficiency changes to 96.1% from 97% 
P.78 

Exhibit II 

M&D Effects on Onboard Efficiency Based on Loss of System Control Efficiency 

(Without Saturated Canister Vehicle) 

(7•89-1.8)(3)+(16.4-1.8)(!)+(10.05-1.8)(4)+(2.65-1.8)(1)=.359=35.9% Eff Loss 

21 

.359 ( 9 ) = 2.1% fleet average efficiency loss 

156 

(With Saturated Canister Vehicle) 

(7.89-1.8)(3)+(16.13-1.8)(1)+(10.50-1.8)(4)+(2.65-1.8)(l)+(8.43-1.8)(2)=.352=35.21b Eff Loss 

21 

. 352 {_1_1) = 2.4% fleet average efficiency loss 

(158) 
AT'PrQie 

P.79 

A 'Af- 'I 

UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

ANN ARBOR. MICHIGAN 48105 

OFFICE OF 

AIR AND RADIATION 

July 31 , 1987 

MEMORANDUM 

SUBJECT: 

FROM: 

TO: 

MVMA Comments on Gasoline Vapor Risk Assessment 

Charles L. Gray, Jr., Director Ay/^^y^1 y 

Emission Control Technology DivrVion / / ' 

William Farland, Director 

Carcinogen Assessment Group (RD 689) 

Attached is a recent letter from the Motor Vehicle 

Manufacturers Association discussing the gasoline vapor issue 

and recent work by the Chemical Industry Institute of Toxicology 

on the effect of hydrocarbons on kidneys of male rats. This 

issue had been raised earlier in the CAG and HEI reports. 

I am reguesting that CAG review the MVMA letter and 

references and let me know if any changes are needed to the most 

recent CAG report released last April. Also, I would appreciate 

any comments on whether any new information here affects the EPA 

rulemaking package. 

Attachment 

cc: Richard D. Wilson (AR 455) 

James B. Weigold (MD 11) 

Steven C. Nesnow (MD 68) 
2 A \ UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

YSSE^J . ANN ARBOR. MICHIGAN 48105 

'"* PWjt * 

OFFICE OF 

AIR AND RADIATION 

JUL 31 1987 

Dr. Fred W. Bowditch 

Vice President 

Technical Affairs Division 

Motor Vehicle Manufacturers Association 

300 New Center Building 

Detroit, MI 48202 

Dear Dr. Bowditch: 

Your letter of July 6th to Administrator Thomas has been 

referred to me for appropriate action and reply. This letter 

discusses the cell proliferation occurring in the kidney of male 

rats following exposure to high levels of certain gasoline 

hydrocarbons. You cite several papers published this year on 

the recent work of the Chemical industry Institute of Toxicology 

giving new information on this phenomenon. You also state that 

you feel this evidence means that EPA should reassess • the 

potential human risk from the refueling process. 

The Administrator as well as staff in the Office of 

Research and Development (ORD) and the Office of Air and 

Radiation had been aware of this phenomenon from the ORD and 

Health Effects Institute reports. in fact, the most recent ORD 

report titled "Evaluation of the carcinogenicity of Unleaded 

Gasoline" released last April has undergone extensive review and 

discusses this phenomenon in detail. 

I agree with your assessment that there is some uncertainty 

regarding the potential carcinogenicity of gasoline vapors and 

expect this to be one issue raised in comments on EPA's recent 

on-board proposal. Following receipt of comments on this issue, 

EPA will reanalyze this issue. Towards that end, I am 

forwarding your letter to personnel in ORD reguesting any 

comments they have on how the information in the recent ORD 

report should be altered based on these new papers. Also, I am 
P.81 

-2-

forwarding a copy of your letter and this response for inclusion 

in EPA Public Docket A-87-11 concerning on-board vapor recovery. 

Sincerely yours, 

Lc€yy. V 

Charles L. Gray, 

Director 

Emission Control Technology Division 

cc: Richard D. Wilson 

William H. Farland 

Steven C. Nesnow 
P.82 

MOTOR VEHICLE MANUFACTURERS ASSOCIATION 

of the United States. Inc. 

300 NEW CENTER BUILDING • DETROIT. MICHIGAN 48202 • AREA 313-872-4311 

TLXNO. 1009770 AUTOMAKERS DET 

DONALD E. PETERSEN. Chairman 

THOMAS H. HANNA, President and Chief Executive Officer 

July 6, 1987 

Mr. Lee M. Thomas, Administrator 

Environmental Protection Agency 

Office of the Administrator 

401 M Street, SW 

Washington, D.C. 20460 

Dear Mr. Thomas: 

The Motor Vehicle Manufacturers Association of the United 

States, Inc. (MVMA) is concerned that the Agency has not taken 

into account important information on the pending regulation of 

refueling gasoline vapors. As the Agency nears its final 

decision on this matter, consideration should be given to the 

most recent scientific data on gasoline and rat kidney cancer. 

These data indicate that there is no significant health problem 

to humans during the refueling process. 

The most recent experimental information from the Chemical 

Industry Institute of Toxicology indicates that tumors in 

male rat kidneys are related to a regenerative process (cell 

proliferation) which occurs following exposure to a specific 

protein unigue to male rats. This protein is formed in male rats 

in response to inhaled hydrocarbons from gasoline. 

The results of these experimental studies were recently 

presented at two national scientific meetings (1,2). These data 

have shown that: 

1) The rat kidney cell proliferation is induced only by high 

concentrations of the inhaled, wholly-vaporized gasoline. 

The cell proliferation increases with the concentration of 

inhaled wholly-vaporized gasoline and at high levels 

correlates well with the number of rats with renal tumors. 

2) The cell proliferation induction is causally connected 

with the presence of high concentrations of specific 

hydrocarbons (trimethylpentane and similar isoparaffinic 

compounds) in the gasoline. 

MEMBERS: 

AMERICAN MOTORS CORPORATION • CHRYSLER CORPORATION • FORD MOTOR COMPANY • GENERAL MOTORS CORPORATION 

HONDA OF AMERICA MFC. INC. • M.A.N. TRUCK & BUS CORPORATION • NAVISTAR INTERNATIONAL TRANSPORTATION CORP. 

PACCAR Inc • VOLKSWAGEN OF AMERICA. INC. • VOLVO NORTH AMERICA CORPORATION 
P.83 

Mr. Lee M. Thomas -2- July 6, 1987 

3) The cell proliferation and increased DNA synthesis caused 

by these compounds occurs in male but not female rats and 

is due to accumulation of a specific protein produced-only 

by male rats (i.e., and not in man). The accumulation of 

protein leads to cell death and a subseguent cell 

proliferation. 

This new information strongly supports a reassessment of the 

potential human risk from the refueling process. The new data 

reaffirmed previous observations that unleaded gasoline is a 

non-genotoxic material and that the tumor production observed in 

long-term animal experiments was caused by a chronic regenerative 

process. 

It should also be mentioned that in addition to high 

concentrations of unleaded gasoline or trimethylpentane, several 

other chemical compounds are capable of producing hydrocarbon 

nephropathy and renal cancer in male rats. For example, 

d-limonene occurs in various ethereal oils, particularly in oils 

of lemon, orange, caraway, dill, and bergamot and has been for 

many years a significant component of normal human diet. Chronic 

administration of d-limonene produces the same male rat specific 

nephropathy observed in animals dosed with unleaded gasoline. 

The most recent studies conclude that "a laboratory rat is a 

uniguely sensitive and inappropriate model for assessing the 

potential human risk of d-limonene because even the lowest used 

dose...produced chronic nephropathy" (3). 

Since similar male rat nephropathy was a prereguisite for the 

renal tumors observed after long-term exposures to unleaded 

gasoline vapors, the use of the same animal models seems to be 

egually inappropriate for assessing the potential impact of 

refueling vapors on human health. The data from the long-term 

exposure of laboratory rats to wholly vaporized unleaded gasoline 

should, therefore, not be used in the assessment of the public 

health risk from the refueling process. 

We believe that this information demonstrates that refueling 

vapor does not pose any significant health risk to humans. We 

urge you to consider this in deciding on the need for controls on 

retail gasoline marketing. More detailed information and 

references are available on all of the scientific results 

mentioned above. Please feel free to have EPA scientists contact 

me or Richard T. Paul of MVMA staff for further information. 

Thank you for your consideration in this matter. 

Fred W. Bowditch 

Vice President 

Technical Affairs Division 

/tlw 
P.84 

REFERENCES 

1. Swenberg, J.A.: "Species and Sex Difference in Renal 

Carcinogenicity: The Relevance of Specific Proteins and 

Increased Cell Turnover", Presented in the Symposium on 

Biochemical mechanism of Sopccies Differences in Target Organ 

Carcinogenicity, the 26th Society of Toxicology Annual Meeting, 

Washington, D.C., February 23-27, 1987. 

2. Charboneau, M. Short, B.G., Lock, E.A. and Swenberg, J.S.: 

"Unleaded Gasoline-Induced Protein Droplet Nephropathy: 

Relevance of a Male Rat Specific Syndrome Humans", Presented at 

the 1987 Annual Meeting of the Air Pollution Control Association, 

New York, N.Y., June 21-26, 1987. 

3. Ridder, et al, 1987, Webb and Aldeu, 1987. 
P.85 

i A \ UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

\^l4rj

 AN N ARBOR. MICHIGAN 48105 

OCT I 41966 

OFFICE OF 

AIR AND RADIATION 

Mr. Ralph Hitchcock / 

Director, Office of Vehicle 

Safety Standards ' 

National Highway Traffic 

Safety Administration (NRM-10) 

400 7th Street, SW 

Washington, DC 20590 

( ^-ICC-o^Lf^ 

Dear Mr. Hitchcock: 

As promised in our past discussions, enclosed is a copy of 

our technical analysis of onboard vapor recovery systems. As 

part of our continuing coordination on the safety of onboard 

systems, I would appreciate your review of this analysis and 

welcome any comments or suggestions you may have. Specific 

discussions of the safety issues can be found in part 5 of the. 

onboard control technology section. in the near future we will 

be sending you the draft preamble language on the safety issuesand the consultation process prescribed in the Clean Air Act, 

and we will be seeking your concurrence on that language. if 

you have any guestions, please feel free to contact Chester 

France of my staff at 374-8338. 

Sincerely yours, 

yy 

-..^. y y /—:?'-/yy.s^. 

Charles L. Gray, Jr. 

Director 

Emission Control Technology Division 

Enclosure 
i d \ UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

ANN ARBOR. MICHIGAN 48105 

2 21986 

OFFICE OF 

. . T „ . AW ANO RADIATION 

Mr. Kenneth L. Pierson 

Director, Office of Motor 

Cartrier Standards (HMC-1) 

Department of Transportation 

Washington, D.C. 20590 

Dear Mr. Pierson: 

This letter is in follow-up to your re'Cent phone 

conversation with Paul Laing of my staff regarding fuel system 

safety standards for heavy-duty gasoline fueled vehicles. As 

you are now aware, EPA is presently evaluating the feasibility 

and safety implications of controlling refueling emissions 

using an onboard vapor recovery system. To date, our safety 

analysis has focused primarily on the overall crash safety 

implications of onboard controls as evaluated by Federal Motor 

Vehicle Safety Standard 301 tests. However, through recent 

correspondence from Ralph Hitchcock of NHTSA's Office of 

Vehicle Safety Standards, we were informed that your office has 

responsibility for regulations on the safety testing of fuel * 

systems for vehicles over 10,000 lbs. GVWR. We would greatly 

appreciate your cooperation in helping us address any onboard 

safety issues specifically related to these heavier vehicles. 

Along with this letter, we are sending you some general 

background information on onboard refueling control systems and 

the most recent draft of our safety analysis. Although most of 

the current safety analysis deals with issues related 

specifically to light-duty vehicles and trucks, we believe the 

same general safety concerns will apply to heavy-duty vehicles 

as well. The information we requested from your office on 

heavy-duty safety standards will be used to revise our current 

safety analysis to specifically address any heavy-duty vehicle 

concerns. Shortly thereafter, we would appreciate your review 

of our revised safety analysis. 

If you have any questions, please feel free to contact 

Glenn Passavant of my staff at 374-8408 (FTS). We would be 

happy to meet with you in the future to discuss these issues 

further if you believe it would be helpful. Thank you for your 

time and assistance. 

Sincerely yours, 

/' y 

• / 

Charles L. Gray, Jr. 

Director 

Emission control Technology Division 

Enclosure