In Reply Refer Tot RP-2-1 13 m

ttcratoon Oil Coax«ny Attentions P i . P. R. Schneider Poet Office Bo* S3266 Lafayette, Louisiana 70S05

Ge*-Ueuen«

Pe. ..-.cc it ti&de to youi init ial Plain a Bsi/loretion and Enviiomental Report received Fecenbei 30, IMS, aaeoded January 13, 1986, for Least OCS-G 56C5, Hlock 109, Grand Ii>le Area. Tbia i inn n.clucec the activities proioaed fee Weils A, fc, C, C, and Li.

In accordance vith 30 CfP. 250.34, revit.ee? racer^er 13, 1979, enu our lettar cate*. January 29, 1979, thie flan I'UB been determined to be ooiui/lete us» of January 13, 1986, ano it, now bein« considered for an roval.

Tout i lan control number ia n—2375 anu iliofcld be referenced in your conmunAcaLion and cor restvendmi>ce concerning tbia plan.

Sincerely youti,

BajMlSpd: mm*" Acting Regional £ui/crvi*or Rules and Pzcductlon

bcci Leaae OC6-0 5665 (OPS-3-2) (PILE ROOM) 10JP8-3-4 w/PuLiic Info. Copy of the plan and BP (PUBL.REC.)

ttJTolbcrttrbrt1/13/86 Disk la

Pr

JAN i: w&

Information Service! IMeaan

Off i f WHS District Houston Division Exploration Unrtad Sutw

Marathon Oil Company

P.O. Box 3128 Houston, Texas 77263 Tetophon. 713/629-8800

January 6, 1986

Minerals Management Service • - ;.M.. P.O. Box 7944 Metairie, LA 70010-7994 .....

Attention: Mr. D.W. Solanas

Re: Plan of Exploration 0CS-G-5665 Grand Isle Block 109

Dear Mr. Solanas:

In response to your request to limit Plan of Exploration wells to no more than five locations, we request that the following three locations be deleted from the Plan of Exploration submitted December 2c, 1985 on the above referenced block:

Location D 6100' FSL & 2400' FEL Location E 1800' FNL & 5500' FEL Location F 1200' FNL & 500' FWL

Very truly yours.

E. M. Dauernhelm, Manager Joint Venture Leasehold

EMD/JLH/pd LSE005V

xc: E. D. Sneed F. F. Schneider D. K, DePrlest W. J. Shortle/M.L. Mouton A. Morale Amerada Hess Corporation Phi l l ips 011 Company TXP Operating Company

Gulf Coast Offshore District Houston Offshore Division Production Operations United States

.A/-2

2 V l \ Marathon ' Oil Company

P.O. Box 53266 OCS Lafayette. Louisiana 70505-3266 Telephone 318/233-8240

Decanber 26, 1985

Minerals Management Service Mr. D. W. Solanar, P. O. Box 7944 Metairie, IA 70010-7944

PLA'J OP EXPLORATION OCS-C-5665 GRAND ISLE AREA BLOCK 109

Pursuant to Part 250, Title 30, Section I , CFR 250.34, the attached Exploratory Drilling Plan for Grand Isle Area Block 109 i s respectfully submitted. The f i r s t well w i l l be spudded by Pebruary 15, 1986.

The Exploratory Plan includes:

1. A description of proposed activity. 2. A shallow hazards letter (proprietary). 3. A l i s t of proposed locations (proprietary). 4. A schematic of proposed locations (proprietary). 5. A seismic horizon, abnormal pressure and cross section schematics

(proprietary). 6. A non-proprietary plat of surface locations and lease block relative

to shore line. 7. A typical semi-submersible r i g , a diverter system, and a typical

blowout preventer schematics. 8. A l i s t of water base and o i l base mud components. 9. Environmental report.

I f additional information is required, please advise.

F. F. SCHNEIDER DISTRICT DRILLING SUPERINTENDENT EASTERN OPERATIONS

pdh

Attachments

EXPLORATORY DRILLING PLAN GRAND ISLE AREA BLOCK 109

OCS-G-5665

Jt i s proposed to d r i l l at least eight (8) exploratory wells pn the subject lease, OCS-G-5665, for the purpose of evaluating the potential of the lease to produce comnercial quantities of oil and gas.

Odom offshore Surveys, Inc. conducted a high resolution geophysical survey on Grand Iale Area Block 109 fbr Marathon Oil Company. The survey was performed with a magnetometer, a sub-bottan profiler, a side scan sonar, an echo sounder, and a DFSV digital seiamic system with a 160 cubic inch water gun as che energy source.

Interpretation of the seismic information allowed the generation of the attached structure maps and a cross sectional schematic of che area showing the expected depths of marker formations. Additional geophysical data will be obtained as warranted as new inforraation is gained during drilling activity.

Based on the present interpretation of seismic information, locations of the proposed wells are listed in ths attached proprietary information copy.

The exploratory vork is to bs done with one or more semi-suhmersible type mobile drilling rigs. As each well is drilled and new information is obtained, the locatior. and number of subsequent wells on the block may change. This contingency is required in order to ontLaize the evaluation of the block with a minimum cf wells in the most strategic locations.

Eoch exploratory well ie projected to require a minimum of 60 days to dr i l l and evaluate. Present scheduling indicates that the f irst well will be spudded approximately February, 1986. Because ar eight (8) well program will require at least 480 days of continuous drilling activity, the complete program as affected by present and future rig scheduling, is projected to extend through May, 1987.

The service base for this exploration program will be Venice, Louisiana. Numerous service facilities, including storage areas, pipe yards, mud companies, helipads, docks, and other related services, are located here and are deemed adequate to support this exploration program.

The Oil Spill Contingency Plan for Marathon Oil Ccmpany WAS approved December 27, 1984. Marathon is a nwraber of Clean Gulf Associates. In the event of an oil sp i l l . Clean Gulf's service ecui-vmint from Venice, Louisiana will be utilized for cleanup operations. Oil spil l respond time is astimated to be ten (10) hours for ths Workboat Mounted Fast Response Systems and twenty (20) hours for the Boas Barge Open Sea Skimmer System.

Gaseous Air Emission projections are located in the attached environmental report.

OLC.iO 1985

Surface Location

6400-4750' 2100' 6100 • 1800' 1200' 5400' S400'

FSL 6 FNL 5 FSL Q FSL 6 FNL 6 FNL 6 FSL a FSL $

5300' 6100' 3800' 2400' 5500' 500' 4700' 5700'

FEL FWL FEL FEL FEL FWL FEL FWL

2 30

257

108

Marathon Oi l Company

O C S - G - 5 6 6 5

BLK. 109 A 6

IIO

I 17

VICINITY PLAT PROPOSED MINERAL DEVELOPMENT

GRAND ISLE AREA G U L F CF M E X I C O

APPLICATION BY DECEMf.f*-

M A P A T H ON O i i . CCMFANY . . A F A Y E T ' E , L <i

i I

J M L'rt J r r r r TTmrrrr -~7 "Mi&W; •:/•>,:. V'V.?(riv/ i

' 1 I TYPICAL SEM I-SUBMERSIBLE RIG

PROPOSED MINERAL DEVELOPMENT GRAND ISLE AREA G U L P OF M E X I C O

MARATHON U L ~.G. LAFAYETTE. LA .

WATER BASE MUD Q31P0NENTS

GULF OF MEXICO

Category

Gelling Agent

Weight Material

Thinner

Viscosifier

Lost Circulation Material

Corrosion Inhibitor

pH Control

Lubricants

Various O.enicais

Composition

Wyoming Bentonite Clay Attauulgite

Barium Sulfate Barite

Sodium Acid Pyrophosphate Leanardite Phosphate Lignite Resign Soaps Sodium Tetraphosphate Ferrochrome Lignosuifonate Chrome Lignosuifonate Polymeric Lignosuifonate Aluminum Chrome Lignosuifonate Calcium Lignosuifonate Hemlock Bark Extract Gilsonite Quebracho

Starch Carboxymethyl Cellulose Sodium Hexametaphospnate Pelletited Asbestos

Cellophane Mica Flakes Ground Nut Hulls Expanded Perlire Diatcmaceous Earth Shredded Leather Rice Hulls

FiL-aing Amine

Potassium Hydrate Caustic Soda

Detergent Castor Oil Alcohol

CaCU CaCo:

OIL BASE MUD CXMPONEHTS

GULF OF MEXICO

- Category

Gelling Agent

Weighting Agent

Thinner or Bnulsifer

Water Loss Control Agent

pH Control

Lost Circulation Material

Various Chemicals

Composition

Organophylic Clay

Barite or Barium Sulfate

Organic Fatty Acid Amines

Modified Asphattine

Lime

Cellophane Mica Flakes Ground Nut Hulls Expanued Perlite Oiatcmaceous Earth Shredded Leather, Rice Hulls

Oil Diesel CaQ2

ENVIRONMENTAL REPORT

PLAN OF EXPLORATION

GRAND ISLE BLOCK 109

OCS-G-5665

MARATHON OIL COMPANY

DECEMBER 31, 198F

COMPANY CONTACT PERSON: MR. ROBERT J. COROES MARATHON OIL COMPANY P. 0. BOX 53266 OCS LAFAYETTE, LA 70505 PHONE (318) 233-8240

INTRODUCTION

Marathon 011 Company plans to conduct exploratory d r i l l i n g

operatlonr at Grand Isle Block 109. This area Is located

approximately 58 miles south of Grand I s l e , Louisiana.

The objective of the proposed a c t i v i t y 1s outlined 1n the Plan of

Exploration. Bri e f l y , the objective is to d r i l l 8 straight

exploratory »e11s. A semisubmersible exploratory d r i l l i n g r i g

w i l l move on location by February, 1936. The duration o' ihe

d r i l l i n g a c t i v i t y Is estimated at 60 days per hole for a tocal

project duration of 480 days. The exploration a c t i v i t i e s w i l l be

completed by May, 1987.

NOTE: The information included in this Plan follows the

Guidelines for Preparation of Environmental Reports for Coastal

Management Consistency Determination by the States of Alabama,

Louisiana and Mississippi. Sections are designated in this

report to conform with those of the Guideline.

DESCRIPTION OF THE PROPOSED ACTION

a. Travel routes for supplies and personnel w i l l be from Venice,

Louisiana to the project area u t i l i z i n g workboats and

crewboats.

One round trip per boat will usually occur every one to

two days. Helicopters will provide air service averaging one

flight per day.

manned and will not require additional personnel. Similarly,

no significant adjustment in activity levels or faclli'.i >s Is

expected In tnrfllsry companies such as warehouses, mud

companies, pipe storage yards, heliports, and other service

companies.

A l i s t of employees to be used in the proposed operations

offshore and onshore Is listed below. The list is typical,

though the exact number of employes. ».?v vary day by aay.

Offshore

b. The Marathon shorebase at Venice, Louisiana is already

Posltion {*•:.».: j " of Em pi oyees

2 2 5 2 1 2 S 1

1 2

1 i

Total, 2 ".rv>ts = 56 persons

Onshore

Posi t i on Number of employer

Warehouse and wharf Helicopter Crewboat Supply (work ) boat

6 3 < 7

T o t a l , 1 , 2 crews « 40 persons 20

The d r i l l i n g r i g v t l l i z e d in Lhe project w i l l be occupied by

approximately 66 pe.'.ns. These workers are currently

assigned to the d r i l l i n g r i g . No additional personnel w i l l

be required as a resuH of the d r i l l i n g a c i t v i t i e s .

c. No new support f a d l i t i t ' , w i i 1 be needed for the propose^

actl v1 ty.

d. No new techniques or unusuai techno,o^y w i l l be used.

e. Travel w i l l be from Venice to Graic Isle Block 109. V-rual

No. i shows the location of the project with respect tr v e

nearest coestal areas.

f. Pipel ne routes, et:. sr« not applicable at this tim;*.

AOPITiCHAI INP Or.MAT iC^

Potential wast.' products from the project w i l l include domestic

solid wastes, sanitary wastes, and d r i l l i n g f l u i d s . D r i l l i n g

flulas u t i l i z e d in the project may be both o i l based and water

based d r i l l i n g muds. Onsnore disposal of d r i l l i n g r • w i l l

depend on che composition of the mu-?. °otential components of

the d r i l l i n g f l v i i d system wil'. include these components commonly

uti l i z e d in this ty Pe of a c t i v i t y . These components are listed

in the Plan of Exploration.

The Marathon 01 ! pany Gul f Coast Offshore D i s t r i c t Oi l S p i l l

Contingency Plan; submitted to .he M.M.S. on Decmeber 5, 1984

and approved December 27, 1 9 f t . d.;cusses contingency puns fo r

p reven t i ng , r e p o r t i n g , and d e f i n e , up s p i l l s of o i l or waste

m a t e r i a l s . The Contingency Plar describes p o l l u t i o n prevent ion

procedures and r e s p o n s i b i l i t i e s for Marathon Oi l Company

employees and cont rac t personnel . p e c l f l c dut ies fo r Marathon

employees involved 1n the Implementation of contingency plans are

o u t l i n e d 1n the Oi l S p i l l Contingency Plan. The dut ies of

con t rac t o i l s p i l l cleanup companies JU- also addressed.

Marathon 01" Company I * * member of Clean Gulf Associates (CGA).

: che event of a major s p i l l , equipment owned by CGA would be

u t i l i z e d in the s p i l l con t ro l and cleanup e f f o r t . CGA maintains

s p p i roftt.ral and cleanup equipment at var ious coastal

comauTn't' s on t..e fijtf Coast (Clec.n Gui f A i : o c f a t e s , Operation

Manual. 983) i n c l u d n i j Grand I s l e , Venice, Gf«» ia , and Houma,

Lou is iana . Each of tr.ese l oca t i ons is r e l a t i v e l y nrcximate to

the p r o j e c t s i t e .

I t is Marathon Oi l Company's po l i cy that a l l employees a.r»d

con t rac to rs w i l l comply w i th the p o l l u t i o n prevent ion

requirements of ICS Orders 5 and 7.

- 4 -

3. DESCRIPTION OF TH£ AFFECTED ENVIRONMENT AND IMPACTS

a. (1) Grata Isle Block 109 ir not know , to be in an

environmentally sen itive area While the d r i l l i n g rig is

located over the proposed well sites, 2.5 to 5.0 acres of

seafloor will be removed from commerlcal bottom fishing.

Grand Isle B1 oc* i'j? Is not located near any major oyster

area?. The block lies within the limits of the industrial

bottomflsh harvest areas as well as the principal menhaden

harvest area as shown on Visual 4-1 of the Mineral

Management Service Environmental Impact Statement Visuals.

The project is not expected to impact commerlcal fishing

slgni fIcantly.

(2) Grand Isle Block 109 lies outside of any maj.u-

dipping fairway, anchorage area, or transit lane.

(3/ The use of pleasure craft in the project area may be

directly affected by the presence of the dr i l l i n g rig. A

discussion of these impacts can be found in ..he Final

Regional Environmental Impact Statement for the Gulf of

Mexico published in January 1983.

Maratiion 011 Company was a participant of the Minerals

Management Service sponsored study of the recreational use

a s soc4 * ved with petroleum structures. The objective of

the stu^; was to document the number or pleasure boati

asset *' a: »d with OCS recreational fisning. Although the

study .as '>een concluded, Mv *. Wor, will continue to

suppo< • pleata.** -nd sport f'^.tng on tho OCS

5-

(4) Orard a'aclc 100 1s located outside the historical

cultural resources probability l i n e . The proposal' well

t1te; ap •ar to be located In an area with no unmanageable

sri«*low d r i l ' ng hazard: or arcr.eelogical Sites* The

block seafloor *'*cws ;.o evidence or drowned archeological

or cultural resorccs.

(5) The project cr*a 1s not proximate to earlne sanctuaries or

breeding grounds. Wildlife refuges, breeding and spawning

grounds, and marine and estuarine sanctuaries w i l l not be

affected by a c t i v i t i e s associated with this project.

(6) There Is no Indication of pipeline., or other lanmade

structures near the proposed well sites. No (noun cables

or pipelines exist on Grand Isle Block 109.

(7) There are no other known alnera's uses at Grand Isle Block

109.

(8) The geology of Grand isle Block 109 i : variable, surface

geology consists s-iaarily of s i l t y 'ay sediments.

Geologic featu'i'i Include coastal anc Shelf Deposits.

Specifics of the block geology are Included In the Plan of

Exploration.

-6-

Tht •ost significant source of solid wastes for the proposed

activity 1s cuttings from the bore hole and associated

drilling fluids. The cuttings are normally dumped at the site

and consist of rock particles ranging from grain to pebble

size. The amount of cuttings from a 10,000 foot well Is

estimated to be 1,000 tons.

Impacts on the environment from these cuttings would Include a

burying of benthic organisms found at the rig site. Duration

of this Impact would be short as the cutties will settle to

the bottom. The overall impact on benthic organisms will be

of a localized and temporary nature. A 11st of drilling mud

additives utilized t*. tte* -t/ojecI Is Included In the Plan of

Exploration.

The cuttings are processed over a shale shaker and washed to

remove drilling mud and oil from them. Some of the mud may

become entrained with che drilling fluids and cause a

turbidity plume. The long term effects of the plume are not

known a'though localized impacts on the phytoplankton

population can be expected. No oil based drilling fluids will

be discharged overboard.

Wintt- and summer currents In Grand Isle Block 109 run

generally to the northwest at 36-41 cm/sec with occasional

variances.

-7-

Grand Isle Block 109 does not lie In a U.S.E.P.A. approved

Ocean Dumping Site.

(9) Four species of aarine turtle occur in the Gulf of Mexico.

These are the loggerhead, green sea turtle, Atlantic

Ridley, and hawksbill. These turtle species are on the

endangered species l i s t . Turtles In the vicinity of the

project area would be vulnerable to major oil spills and

possible collisions with boats. The potential for an oil

spill 1s remote. No turtle nesting grounds are located in

the vidnity of the project area, transportation routes,

or shore support base. There Is little reason to suspect

disruption of turtle migrations.

Of the marine mammals occurring in the Gulf of Mexico, the

sperm whale, black right whale, sei whale, fin whale, and

blue whale are on the endangered species l i s t . Lowery

(1974) presents a discussion of the state of knowledge of

the marine mammals off the coast of Louisiana and Texas.

From the Information presented, It appears that any

endangered whales discovered in the project area would be

strays, if they occurred at all. Resident populations of

these whales are either In colder waters, deep waters, or

more tropical waters. Porpoises of the genus Stannella,

Tursiops, and Del phi nus are expected to commonly occur 1n

the project area.

-3-

The whooping crane and brown pelican were listed as

endangered In 1967 and 1970, respectively. The

transportation routes fron the project area to the

shorebase (Venice, Louisiana) are not in the vicinity of

the critical habitat for these species.

-9

b. No socio-economic data beyond that already provided

Is required.

UNAVOIDABLE ADVERSE IMPACTS

An unavoidable and Irreversible Inpact to the geology will

occur due to the removal o* rock cuttings froa the

subsurface strata. This impact is considered negligible.

The water quality In the immediate vicinity of the drilling

rig will be temporarily degraded by the turbidity resulting

froa the drilling fluids and cuttings. Iapacts on the biota

of the area will be of aixed quality and duration. The

negative Iapacts will Include the burying of Lenthlc

organlsas by the cuttings and the minor decrease In

phytoplankton productivity due to the drilling aud plume.

Organism recovery rates would be dependent upon seasonal

reproduction cycles and recolonization by Indigenous and

other spedes. Estimates for recolonization range froa

aonths to several years.

These Impacts are justified due to the temporary nature of

the effects of cuttings disposal on local water clarity and

benthic organisms.

5. REFERENCES

The following information sources were used in the

preparation of this document:

Clean Gulf Associates, Operations Manual, 1983

Lowery, G. H., Jr., The Mammals of Loulsi ana and Its Adjacent Waters, LouTsTana stateUm versi ty, T9T4

Marathon Oil Company, Gulf Coast Offshore District Oil Spill Contingency Pl an, Lafayette, Louisiana, 19IT4"

U. S. Department of the Interior, Minerals Management Service, Final Regional Environmental Impact Statement, Gulf of Mexico c

U. S. Environmental Protection Agency, Compilation of A1r Pollutant Emission Factors, 3rd Edition, AP-42, 19/7

Zingula, R. P., "Effects of Drilling Operations on the Marine Environment," Environmental Aspects of Chemical Use i_n Well Dr i l l ing Operations, EPA SCOil-;5-00T,T7T5

The proposed activity on OCS-G-5665; Grand Isle Block 109

will be carried out and completed with the guarantee of the

following Items:

1. The best available and safest technologies will be

utilized throughout the project. This Includes meeting

all applicable requirements for equipment types, general

project layout, safety systems, and equipment and

monitoring systems.

There will be no new or unusual technologies utilized

throughout the project.

-11-

No new employment for related onshore fa c i l i t i e s w i l l be

required as a result of this projected activity.

All operations wil l be covered by a M.S.S.-approved oil

spill contingency plan. Marathon's Gulf Coast Offshore

District Plan dated December, 1984, for the preventing,

reporting, and cleaning up spills of oil or waste

materials, was approved December 27, 1984.

(See Appendix I)

All applicable Federal, State, and local requiremencs

regarding air emission and water quality for the

proposed activities, as well as any permit conditio:*,

will be complied with.

COASTAL ZONE MANAGEMENT

CONSISTENCY CERTIFICATION

PLAN OF EXPLORATION

Grand I s l e B lock 109

OCS-G-5665

The pi d e s c r i b e d i n d e t a i l i n t h i s p l a n comply

w i t h the S t a t e o f L o u i s i a n a ' s approved Coas ta l Zone Management

P r o g r d * and w i l l be conduc ted i n a manner c o n s i s t e n t w i t h such

program. A r e q u e s t f o r p u b l i c a t i o n o f P u b l i c N o t i c e o f a P lan

E x p l o r a t i o n has been made w i t h the S t a t e T imes , the o f f i c i a l

Lou i s i ana s t a t e j o u r n a l . The n o t i c e w i l l be p u b l i s h e d i n the

l e g a l Ad S e c t i o n of the S t a t e Times i n J a n u a r y , 1986.

MARATHON OIL COMPANY

W. Z. rfourke D i b t r i c t P r o d u c t i o n Manager Eas te rn Area

APPENDIX I

Notice of U. S. Geological Survey (Minerals Management Service)

Approval of the Marathon Gulf Coast Offshore District Oil Spill

Contingency Plan.

-14-

PLAN OF EXPLORATION GRAND ISLE BLOCK 109

GASEOUS AIR EMISSION PROJECTION TOTAL SOURCES

rborne pollutants In thi? j-ojecc will be generated by engines on the drilling g, supply and transport » 'ts, ana helicopters. Attached are summaries of the

rejected emissions from ea* of *nese sources for one year as well as for the .tion of the project. Th* s n of these projected emissions were used to

calculate the total projected r.«i$sions and the exemption status as listed below.

EMISSION EXEMPTION TOTAL PROJECTED EMISSION, PARAMETER AMOUNT (Tons/Year) T Yr. Duration (Tons) STATUS

S02 1931.40 13.33 EXEMPT

TSP 1931.40 14.33 EXEMPT

N0X 1931.40 239.81 EXEMPT

CO 50,944.39 44.41 EXEMPT

VOC 1931.40 16.07 EXEMPT

Emission exemption amounts are calculated based on the following formulas from CFR 30, Part

2570.5/-».

E « 33.3D (For SO2, TSP, N0X, and VOC)

E - 3400D2/3 (For CO) Where E is the emission exemption amount in tons per year and D is the distance of the facility from the closest onshore area of a State expressed In statute miles."

-is.

PLAN OF EXPLORATION GRAND ISLE BLOCK 109

GASEOUS AIR EMISSION PROJECTION DRILLING RIG EMISSIONS

PROJECTED 480 DAY EMISSION FACTOR* PROJECTED ONE YEAR PROJECT DURATION

PARAMETER (lb./Hp-hr.) EMISSIONS (Tons) EMISSIONS (TONS)

SO2 2.0507 x IO" 3 4.88 6.42

TSP 2.2026 x IO" 3 5.23 6.87

N0X 3.0337 x IO" 2 73.16 96.21

CO 6.674 x IO" 3 15.83 20.82

VOC 2.467 x 10 5.85 7.70

TOTAL PROPOSED DEPTH ON POE * 8(13,000') = 104,000' •

PR0JEC1ED ONE YR. EMISSIONS • (365 DAYS)(104,000')(60 HP-hr) 480 DAY5 f t

**(EMISSI0N FACTOR lbs)( TON ) HP^fir ZOOO TB".

TOTAL PROJECTED EMISSIONS = (104,000')(60 HP-hr)(EMISSION FACTORH TON )

f t 2000 lb.

* Emission factors taken from "Compilation of Air Pollutant Emission Factors", 3rd Edition. AP-42, U.S.E.P.A., 1977, pgs. 150-151.

** 60 Hp-hr d r i l l i n g power requirement taken from "Atmospheric Emissions from Offshore Oil and Gas Development and Production, EPA-450, 1977, pg. 86.

-16-

PLAN OF EXPLORATION GRAND ISLE BLOCK 109

GASEOUS AIR EMISSION PROJECTION WORKBOAT SOURCES

Workboats w*y consume up to 45,000 gallons of fuel per month. Based on this quantity of fuel consumed, the projected emissions from this source w i l l be as follows:

PARAMETER

S02

TSP

EMISSION FACTOR* (lbs/1000 gal fuel)

31.2

33.5

PROJECTED OWE YEAR EMISSIONS (Tons)

8.<

9.05

PROJECTED EMISSIONS 460 DAY PROJECT DURATION

11.08

11.89

N0X

CO

V'JC

469.0

102.0

37.5

126.63

27.54

10.13

166.51

36.21

13.31

PROJECTED EMISSIONS -(45000 GAL/MOMNO. OF MONTHS ON PROJECT)(EMISSION FACTOR)( TON )

1000 GAl 2000 l b .

'Emission factors are based on data from "Compilation of Air Pollutant Emission Factors, "3rd Edition, AP-42, U.S. EPA, 1977.

PLAN OF EXPLORATION GRAND ISLE BLOCK 109

GASEOUS AIR EMISSION PROJECTION HELICOPTER SOURCES

Helicopters used 1n this operation are expected to Make one trip per day during the 480 day project duration. While In the immediate vicinity, emissions wili occur during takeoff and landing. Projected Emissions are as follows:

EMISSION FACTOR* PROJECTED ONE PROJECTED EMISSIONS PARAMETER (lbs per cycle) YEAR EMISSIONS (Tons) 480 DAY PROJECT OURATION (Tons)

S02 0.18 0.03 0.04

TSP 0.25 0.05 0.06

N0X 0.57 3.10 0.14

CO $.7 1.04 1.37

VOC 0.52 0.09 0.12

POROJECTEU EMISSIONS - (EMISSION FACTOR)(TOTAL HO. DAYSH TON )

2000 lb. 'Emission factors are based on du a from "Compilation of Air Pollutant Emission Factors, "3rd Edition, AP-42, U.S. EPA, 1977.

-18-