APR 01 1985 n V p l y lienor To: wP-?-l

Shell i>tf$hcr»! I r e . KXtfiM I on : ^ r . ' . A. py Pus: O f f i c e e< •» 1*9 £ew Or leans , Louisiana '•

Centlew n:

toferew 4 * aaoe t f your i n i t i a l Plan < ' Exp lorat ion r e c e i v e ! March l*s, U ' for L.'««*s t m and u l o c > 5 A - M on-( A - U 3 , r c j m j t v e l ^ Mustawj Is land Arse . This plan Includes the a c t i v i t y proposed fo r a t l I f A, p, ana

IP accordance w i t h '.; CFjJ ZS0.34, rev ised Jcccurer 13. 1971. i « W K ' t t j r date* January 2<-. 1-7", t h i s p lan MS been detcrwlned to M c o l l e t * as fcf A"" »» 19*S, ano Is « w b« ing considered fo r approva l .

Your p lan c o n t r o l nua*er Is H-2071 and should n« referenced I r yowr craw n lca •Jon and correspondence concerning th i s r i a n .

S n c r e l y you rs ,

Oris Sod 1 Dannld Giroir

D. tf. Sotanas &egtonal Sup . ' r vUj r

an.-* Product i r -

bcc: Least OCS-G 71R5 (OPS-3-1) (FILL POOH) Lease OCS-C 7183 (OPs-3-2) (FILE * >')

(QPS-3-4 w/PubllC i n f o . Copy t h . plan (PUBLIC RECORDS W W )

00-7

;UTo1bcrr : qt} :3 / l9 /o5:L. , 1sl t 3b

Office of Program Services

APR 2 1985

Recordi Management Sec: 'cn

Shell Offshore Inc. ^ • £ * S . r v , . - c o - w , N t * O r l e « n , U . u . $ « n a 70t6C

O ' t s n c e West P fOQuCl ion D iv is ion

"MAR 1 4 '385

Mr. D. W. Solanas Deputy Minera ls Marager Operations Support Minerals Management Service P. 0. Box 794* M e t a i r i e , LA 70C1C

Dear Mr. Soianas:

SUBJECT: PLAN OF EXPLORATION MUSTANG ISLAND A-94; A-113 OCS-G 7185; 7189 0FFSH0KE TEXAS

Shell Of fshore Inc. request your approval of the Plan cf Exp lo ra t ion fo r the above capt ioned l oca t i on .

Enclosed are attachments which d e t a i l the intended operat ions along w i th the necessary suppor t ing data and i n fo rma t i on . Those attachments which we desi re to be exempt from disc losure under the Freedom of In format ion Act are so noted wi th the stamp "For Government Use Only".

Should you r e q u i r e add i t iona l i n f o rma t i on , please contact P P (Dick) Gramer, J r . o f t h i s s t a f f at (504) 588-6012.

Yours very t r u l y ,

R. A. Haley

D iv is ion Product ion Admin is t ra t ion Manager

RPG:CLB

Attachments

CADH8505203

INDEX r ATTACHMENTS

PLAN OF EXPLORATION

Attachment No. Descript ion No. of Copies

1 Descr ipt ion and Sequence of A c t i v i t i e s 9

2 Pla*. of Surface Locat ion of * e l 1 i ! 9 Structures

3* Plet of Bottom Hole Location of Well 5

4A* Geologic S t ruc ture tiep 5 4B* Geologic S t ruc ture Map 5

5A* Schematic Cross Sect ion 5 5B* Scheme t i c Cross Section 5

6* Shallow D r i l l i n g Hazard Rt. . r t 5

7 Rig Descr ip t ion g

8 Mud & Completion F lu id Components & Add i t i ves 9

9 Oi l S p i l l Contingency Plan 9

10 A i r Emissions Data c

11 Location Mop w i t h Shorebase Descr ip t ion 9

•These attachments are stamped "FOP GOVERNMENT USE ONLY" ard are considered to be exempt from disc losure under the Freedor of In format ion Ac t .

CADH85C 2C2

DESCRIPTION & SEQUENCE OF ACTIVITIES

Shell Plans t o d r i l l up to three (3) exp lo ra to ry wel ls on Mustang Is land A-94, A-113, OCS-G 7189 and OCS-G 7185. The jack -up d r i l l i n g r i g "Mr. Mel" w i l l be used f o r t h i s d r i l l i n g e f f o r t and i s expected to be on l o c a t i o n f o r the f i r s t wel l on or about May 1 , 1985. I f the w e l l s are successful they w i l l be temporar i ly abandoned using mud-l ine c...spension equipment. A l l d r i l l i n g operat ions w i l l be conducted under t p rov is ions of OCS Order No. 2 and other appl icable r e g u l a t i o n s and not ices i - e l u d i n g those regarding the avoidance of po ten t ia l d r i l l i n g hazards, s a f e t y , and p o l l u t i o n prevent ion and c o n t r o l . An t ic ipa ted sequence of a c t i v i t y i s as f o l l o w s :

Lease No. Well No. "Start Dri l l ing Time

Tn3 Lapse

OCS-G 7189 OCS-G 7169 OCS-G 7185

Loc. "A" Loc. "B" Loc. "C"

05/01/85 08/30/85 12/27/85

08/3 '/>5 1 2 , : / , 85 C4/27/86

120 Days 120 Days 120 Days

CADH85C39C3 ATI AG

Y - - 45 .390

OPEN

A93

OPEN

A I M

OPEN

A119

A. 610' E ft • 7 0 0 ' M OF SVV/C

B 2800' E I 5300 S OF H W C

C 6011 ' E 4 200 N OF SW.'C

4000

t =

SURFACE LOCATION MAP OFFSHORE TEXAS

MUSTANG ISLAND A 94. A 113 OCS-G 71U5 7189

ATTACHMEN1 Z

Mr. Mel Self-Elevating Mobile Platfonn

f •

Specifications Length

230 feet (70 1 meters)

freed* 200 feet (61 0 meters)

Pagan 26 feet 17 9 meters)

Drilling Slot 50*41 feet (15.2 »12 5 meters)

Quart art Sleeping accommodations for 74 men with

ynpiefe messing facilities Air conditioned

n m p o n 71 foot (21 6 meter) diameter

Depth Rating Operating Water Depth 350 feet (106 7 meters) non-hurncane season. 275 feet (83 3 meters) hurricane season Drilling Depth 30.000+ feet (9.144 meters)

Cteu tnca t ton Constructed in accordance with Amencan Bureau of Shipping rules A 1 $ Drilling Platform United States Coast Guard certificated

Storage Capacities Bulk Material

Si* 1.050 cu f t (29 7 cube meters) *P" Tanks

Sack Malar ia l 5.000 sacks

Liquid Mater ia l 1.700 DDIS

Drilling Water 5 425 DBS

Nat OS 3.170 bbis

Potable Water 945 bbls

Drilling Equipment Derrick

LeeC Moore 147x30*30 toot (44 8x91x91 meters) 1.320 000 lbs capacity designed for 100 MPH wind load with 18.000 feet (5486 4 meters) o« 5" drtf pipe racked

Substructure Longitudinal and transverse skidding to permit drilling of 5 wells from 1 location.

Orawworiu National C-1625 DE driven by 3-1000 HP motors

Rotary Table National C-375 driven by 800 HP motor

Pi tana Movers 3- EMD SR 16 Diesel Engines Driving 3-1500 KW Alternators and Hutchison-Hayes SCR System

Auxiliary Power 2-EMD SR8 Diesel Engines Driving 2-700 KW AC Generators

Mud Pumpa 2-Nalional 12P-160-71/2" x l2 " Tuple* driven by 2-800 HP motors 1 -National 9P-100-6Vi"x9'i" Triplex driven by 2-800 HP motors

Mixing Pumpa 2- 6*8 Centrifugal each wMOO HP motors

Cc man ting Twin HT-400 Halliburton Cementing Unit

Electric Log Schlumberger

Blowout Prevention •>0" Hydnll 2.000* 13V(" Hydnl Type *GK" 5000 H ;S service 13V Cameron - U" double 10.000 H,S service 13'-*" C jrneron ' U ' single 10.0u0 H2S service Ai' oper 'ted by 2 • 80 gallon Koomey Pieventor Control System with Master Panel on Rig Floo-and Remote Controls

Moor i ng

4- LeTourneau W-1 SOOTS Electric anchor winches

3- 45 Ton LeTourneau electric cranes w'100 foot (30.5 meters) booms

S C K ^ W K i I ant ml Of M»r 19*$ MoOWcteons ana t j D i ' W n n i m i , " . L F btt-- mmO* iuO:«ouf* ,

MUD & COMPLETION FLUID COMPONENTS &

ADDITIVES

I . ITEMS USED ON A ROUTINE BASIS:

T R A D E N A M i". S

IMCO BARCID MILCHEM MA ̂ COB/. DESCRIPTION

Itnco Bar Barite/Baroid B a r i t e / K i l b a r Barite, Mage aar Barite (Barium Sulfate)

Imco Gel Aquagel ! ! i l p e l Magcogel Bentonite Imco Lip Carbonox Ligco Tannathin L i g n i t e RD-111 Q-Broxin Uni Cal Spercene Blended Lignosulfonate Caustic Soda Caustic Soda Caustic Soda Caustic Soda Sodium Hydroxide Aluminum Aluminum Aluminum Aluminum Aluminum

Stearate Stearate Stearate Stearate Stearate Lime Lime Lime Lime Calcium Hydroxide Imco Thin CC-16 Ligcon XP-20 Modified L i g n i t e Soda Ash Soda Ash Soda Ash Soda Ash Sodiun Carbonate

Bicarb Bicarb Bicarb Bicarb Bicarbonate of Soda Poly Rx Durenex Chemtrol-X Resinex Selected Polymer Blend Imco MD Con Det. M.D. D-D Detergent Foamban De f earner LP- 8 Magconol Defoamer (Usual}y alcohol

based)

I . ITEMS USED LESS FREQUENTLY:

DMS Ak t a f l o s DM? DMS Nor.ionic Mud Surfactant

Imco Loid Ir.nernex Mi .starch My Lo Gel Frefrt l a t i n i z e d Starr?

CMC Cellex 0>*C CMC Sodium Carboxy Kethv'l Cellulose

Cypari Cypan Cypan Cypan Sodium Polyacr l a t e

Perr.ai.oid Dextrid Perma-Lose Poly Sal Organic Polymer Drispac Drispac Drispac Drispac Polyanionic Cellulose G>T Gyp Gyp Gyp Gypsum (Plaster of Paris) HME'Superdril KME/Superdril KME/Superdril HME'Superdril G i l s o n i t e (treated) -

Natural Hydrocarbon * Wetting Agent

Black Magic Black Magic Black Magic Black Magic Mud Concentrate f o r Supermix Supermix Supermix Supermix s p o t t i n g f l u i d

Lubrikleen Torq Trim Lubrisal Ma golube Organic Lubricant Imco Myca Mica T o Mil-Mica Mago-Mica Mica-Flakes Imco Plug Wall-Nut Mil Plug Nut Plug Ground Walnut or other

nut h u l l s I r o n i t e I r o n i t e I r o n i t e I r o n i t e Synthetic I r o n Oxfde,

Scavenger _ - Mil Gard - H2S Scavenger (Zinc

Carbonate) Separan S( ̂ aran Separan Separan Polyacrylamide Polymer

ATTACHMENT

I I . I l g iLUSED LESS rREPlTvnv . (CONTINUED)

Salt SAPP

Sa l t SAPP

KCL KCL

1 1 1 • OIL BASE MIT):

IMCO

Imco Spot

Ker.ol-S

Ken-Gel

Ken- Cal-L

VR

BAROID

Skot Free

Invermul

Geltone

D r i l l t r e a t

Duratone

Salt SAPP Shale Trol KCL

MILCHEM

Mil-Free

Carbo-Tec

Salt SAPP

KCL

MAGCOBAR

Pipe- Lax

Oilfaze £ V e r t c i l

Carbo-Gel VG-69

Carbo-Mul

Carbo-Trc:

DV-33

DV-22

OIL BASE

SFT L Supermix

OB Gel

SA-4 7

Chem V

Sodium Chloride Sodium Acid Pyrophosphate Organo/Aluminum Compound Potassium Chloride

DESCRIPTION

Emulsifiers for spot t i n g f l u i d s

E m u l s i f i e r s , g e l l i n g agents and f l u i d loss agents f o r o i l ir.uds

O r g a n i p h i l l i c clays f o r v i s c o s i f y i n g

Asphaltic V i s c o s i f i e r

Organic wetting agents

Fluid loss agents I V - Pl'MP-DOU-N I INHIBITOR FT l'Tiw

Norco No. 6 Refined Oil L Ko. 2 Diesel + 1' v r - uiesel + l„-3. Corrosion I n h i b i t o r s .

V. METHOD OF DTSP.^M •

OIL SPILL CONTINGENCY PLAN

Shell's current "Sp i l l Prevention, Containment, and Counterneasure Plan" was approved by the MMS on October 16, 1984. The wcrk proposed herewith rel ies primarily on the s p i l l equipment stored at the Clean Gulf Associates' bases in Port O'Connor, Texas. A l i s t of available equipment at these bases, plus other bases from which additional equipment can be drawn, is itemized 1n our approved SPCC Pin-.. Section I I I of the approved SPCC Plan l i s t s the preventive measures to be tjktrn to minimize o i l sp i l l s and the reporting procedures to be followed in th.- event one occurs. Section VI provides a detailed discussion of clean-up proc Cures to be i n i t i a t e d , indudir.g a l i s t of the personnel which make up the cle?n-up organizat ion. The training of these personnel 1s summarized in Section V I I I . Assuming two hours to load out the equipment and a 12 knct cruising, a Fast Response Unit can normally be on location wi th in 7 hours.

CADH8505201 ATTACHMENT

PROJECTED EMISSIONS OCS-C 7185 & 718? LEASE

MUSTANG ISLAND BLOCKS A-94 & A-l13

DRILLING RIG

Table 4-2 of EPA 45073-77-026 report entitled "Atomospheric Emissions from Offshore Oil and Gas Development and Production" shows that for a typical d r i l l i n g r i g , 3400, 1900 and 300 horsepower are required for (1) d r i l l i n g ; (2) t r i p p i n g , casing and coring; and (3) surveys and logs, respectively. Table 4-3 of this same report provides a scenario of a 30-day, 10,000-foot wall indicating a total horsepower usage of 597,200 hp-hr. I f i t Is assumed that the same breakdown of r i g a c t i v i t y and power requirements is applicable to the proposed exploratory program, then the power usage w i l l be approximately 2,388,800 hp-hr/well. Based on the emission rates for o i l -fired reciprocating engines (Table 4-A), the following gaseous emissions would be generated for each well during the 120-day d r i l l i n g operation:

DISCHARGE (METRIC TONS)

PEP. WELL ANNUAL RATE

30.82 93.7

so2 2.08 6.3

HC 1.03 3.1

CO 4.51 13.7

Particulates Unknown Unknown

WATER TRANSPORTION

The horsepower usage of the two vessels to be used ln connection with operation i s as follows:

190 Ft. Cargo Vessel

2400 hp X .75 (load factor) X 10 hrs. X 14 tr i p s X 4 months - 990,670 hp-hr.

t r i p s month

80-100 Ft. Standby Vessel

165 hp X .80 (load factor) X 23 hrs. X 120 davs - 364,320 hp-hr. day

1000 hp X .75 (load factor) X 1 hr. X 120 days - 90,000 hp-hr. day

TOTAL 1,444,790 hp-hr.

CADM8501A05 ATTACHMENT /

Based on Table the goseous emissions generated by water t r a n s p o r t a t i o n as follows:

DISCHARGE (METRIC TONS)

PER WELL ANNUAL RATE

N Ox 18.64 56.7

so. 1.26 3.8

HC 0.62 1.9

CO 2.73 8.3

Particulates Unknown Unknown

TOTAT ANNUAL DISCHARGE (METRIC TONS)

CO 22.0

TSP, S02, N0X, VO 165.6

The cargo vessel may serve other fields so that Laa gaseous emissions from vessels chargeable to the operation would be somewhat less.

Emission Exemptions

The proposed location is A2 miles free the nearest shoreline. Therefore, th emission exemption (E) for the various pollutants i s as follows:

C 0 E - 3400 ( 4 2 ) 2 / 3 - AI.081 Tons/yr.

TSP

so2

N 0 X E - 33.3 (42) - i ,399 Tons/yr .

VOC

CADM8501405