In Reply Refer To: RP-2-1 MAY I 6 1985

Sohio Petroleum Corpany A t t e n t i o n : Hr . Cary W. Ke r l i n Post O f f i ce Box 51468 Lafayet te . Louisiana 70505

Gentleaen:

Reference 1s aade to your Supplemental PUn of Explorat ion rece iver Kay 9. 1986. fo r Lease OCS-G 6899. Block 930. Viosca Knoll Area. This p lan Includes the a c t i v i t i e s proposed f o r Wells B and C.

In accordance w i t h 30 CFR 250.34, r ev i s . c Decenfcer 13. 1979. and our l e t t e r datec January 29. 1979. t h i s plan has keen detcrtolnetf to be conu\ete as of May 16. 1986. and 1s now being considered f o r approval .

Your plan con t ro l nunber i s S-1837 and should bo referenced In your COMMA 1 ca t ion and correspondence concem iny t h i s p l a n .

A. Donald G i r o i r Deputy Regional Supervisor Rule* and Production

bcc: Lease OCS-G 6899 (OPS-3-2) (FILE ROOM) COPS-3-4 w/Publ ic I n f o . Copy ot the plan (PUBL.REC.)

KJTolbert:gcw:5/12/86 Disk l a

SOHIOJ SOHIO PETROLEUM COMPANY PO BO»51«t8

OIL CSNTW 8TATX3'

April 30, 1986

Offshors Operations Support U.S. Dept. of the Interior Minerals Management Service P. 0. Box 7944

Hr. 0. W. Solanas, Regional Supervisor PUBLIC

INFORMATION

H e t a l r l e , LA 70f 3-7944

Re: Supplenental Plan of Exploration Viosca Knoll Block 990 OCS-G-6899. Wells B&C Offshore Louisiana

Oear Mr. Solanas:

Please find enclosed five (5) Confidential and six (6) Public Information copies of the Supplemental Plan of Exploration (POZ) for the above referenced project. Accompanying this POE are one (1) set of processed seismic line data offsetting each well location. Two (2) copies of the Hazard Study for Viosca Knoll Block 990 were previously submitted with the Initial POE for Viosca Knoll Block 989 on November 2, 1984.

If you have questions or require additional Information, please call Teresa St. Pierre at (318) 989-4200.

Sincerely,

Cary Vf. Kerlin Regulatory Supervisor Lafayette Oistrict

TLS/brg Attachments

cc: Mr. W. 0. Harris Nr. P. R. Judd

SUPPLEMENTAL PLAN OF EXPLORATION

0CS-u-b899

VIOSCA KNOLL BLOCK 990

OFFSHORE LOUISIAHA

April 30, 1986

LIST QF ATTACHMENTS

A. Letter from Sohlo Regional Geophysicist

B. Vicinity & Well Location Plats

C. Structure Map & Geologic Cross Section

0. Projected Air Emission Schedule

E. Mud Components

SUPPLEHENTAL PLAH OF EXPLORATIOH VIOSCA KNOLL BLOCK 990

OCS-G-6899 OFFSHORE LOUISIANA

Pursuant to the requirements of 30 CFR 250.23.1, Sohlo Petroleum Coinpany sub-

mits the following Supplemental Plan of Exploration (POE) for Viosca Knoll Block

990.

(1) EXPLORATIOH ACTIVITY

The proposed exploration activity for the subject tract consists of drilling

Wells "B & C, In addition to the ore (1) well covered In the Initial POE. The

°B & C" locations will be drilled as straight holes. The estimated time to

dril l these two (2) exploratory wells Is about one hundred fi f t y (150) days.

With a January 1, 1987 anticipated spudding date for the " f l " location.

(11) PROPOSED DRILLING RIG

Sohlo does not have a rig under contract for this project; however, these

wells will be drilled with a semi -submersible type drilling unit similar to the

PACESETTER I I I , which Is owned by Western Oceanic. This rig 1s capable of d r i l -

ling to 25,000' in water depths of 1,580*. Specifications and drawings of this

rig's diverter and BOP system have been sent to your office on November 2, 1984

with the initial POE for Viosca Knoll Block 989.

(111) GEOPHYSICAL WORK

All of the geophysical work preparatory to initiation of exploratory opera-

tions has been completed. A velocity survey may be run on these wells when

total depth has been reached. No other geophysical work is planned unless data

obtained from drilling operations necessitates additional definition detail from

conventional reflection seismic methods.

Supplemental Plan of Exploration Viosca Knoll Block 990 Page 2

A shallow hazard report entitled "Hazard Study Blocks 989 to 990, Viosca

Knoll Area" was prepared by John Chance & Associates, Inc. and two (2) copies

were previously submitted with the Initial POE for Viosca Knoll Block 989.

The Viosca Knoll Block 990 Hazard Study has been reviewed by Mr. Jack Golden,

Sohio's Regional Geophysicist. Attachment A Is a letter from Mr. Golden in

which he agrees with John Chance's conclusions and addresses shallow hazards at

the "B & C" well sites in Viosca Knoll Block 990.

Attachment B-l Is a vicinity map depicting the subject tract's position rela-

tive to the Louisiana shoreline. Ho new onshore facilities will be required for

drilling the proposed exploratory well. Existing service company facilities 1n

the Venice Area have sufficient capacity to accommodate this project without

modification or expansion.

Attachment B-2 shows the proposed surface location for Wells "B C" which

will be drilled as straight holes. The total depth, water depth and surface

locations for each well Is as follows:

Mv) VICINITY AHD LOCATIOH MAPS

Well n 8" TD: Water Depth. Surface Location:

10,500' 1,310' 9.850' FNL 13,070' FEL

Well "C" TD: Water Depth: Surface Location:

10.500' 1.295' 10.840' FNL 14,690' FEL

-2-

Supplemental Plan of Exploration Viosca Knoll Block 990 Page 3

(v) STRUCTURE MAPS AND CROSS SECTIONS

Structure maps and cross-sections are Included 1n the five (5) confidential

copies of this Plan as Attachment C. Oepths shown on cross-sections and struc-

ture maps are sub-sea measure

OTHER RELEVANT DATA

(A) 011 Spill Contingency Plan

Sohlo Petroleum Company 1s a member of Clean Gulf Associates (CGA) and

would utilize that organization's equipment to clean up an oil s p i l l . The

closest CGA bases are at Venice, Grand Isle and Houma, Louisiana, respec-

tively. Response times for CGA Fst Response Units from these locations,

would be 8, 11 and 14 hours respectively. Manpower to operate the CGA's

equipment would be provided by Peterson Maritime, Services, Inc., whose

personnel are trained for o i l spill clean up operations. Sohlo's supervi-

sory personnel would direct the clean up operations until successfully com-

pleted. Additional details can be found in Sohlo's 1985 Oil Spill Contin-

gency Plan which has been approved by the Minerals Management Service.

(B) List of Mud Components

Attachment E 1s a l i s t of the proposed drilling mud components and addi-

tives. Including the common and chemical trade name of each additive.

Supplemental Plan of Exploration Viosca Knoll Block 990 Page 4

(C) Gaseous Emissions

Exploratory drilling operations w i l l be conducted from the surface

sites described 1n Section (1v) using the mobile dr i l l i n g unit des-

cribed in Section (11). Operations w i l l be of a maximum duration of

one hundred f i f t y (150) days.

At the d r i l l site, gaseous emissions will be generated by the rig en-

gines, the attendant work boat, stand-by boat, crew boat, and helicop-

ter, and the production testing of possible prospective reservoirs.

Gaseous emissions at the dock site in Venice, Louisiana, w i l l be gener-

ated by the work boot, crew boat and helicopter. Onshore staging for

this operation will be from existing f a c i l i t i e s , so there w i l l be no

significant increase 1n emission: for this activity. Projected emis-

sions from this activity have been calculated and are presented in

Attachment 0 entitled "Projected A1r Emission Schedule".

(D) Coastal Zone Management (CZM) Consistencv Certification

An Environmental Report and Consistency Certification was included in

the i n i t i a l POE. Proposed activities described In this Supplemental

POE w i l l also be conducted in a manner consistent with Louisiana's

approved CZM programs.

-4-

S O H I O P E T R O L E U M C O M P A N Y

TO: Ray Broussard Lafayette

DATE: January 9, 1986

FROM: Jack Golden

SUBJECT: Site Clearance - Viosca Knoll 990 (OCS-G-6899), Propoaed Location 9,850' FNL; 13,070' FEL; W.D. 1,310'

Gulf Coaat Division Geophysicists conclude that no significant shallow d r i l l i n g hazards exist within 500 feet of the Viosca Knoll Block 990 proposed

well location (9,850* FNL, 13,070' FEL; W.D. 1,310*).

The original records and summary report of a shallow hazard survey conducted by John E. Chance and Associates for Sohio Petroleum Company over Viosca Knoll Block 990 have been reviewed. We are in agreement with their findings and conclude that:

1) No obstructions aie observed on the sea floor within 500 feet of the propoaed location.

2) Selamic data indicate a thick sequence of parallel beds (over 1,000 feet) dip to the east. The rate of dip i s approximately 120 feet per mile.

3) No gas accumulations or faults are observed at the proposed well location within the upper 1,000 feet below mudline (2,310 feet below sea level) or within 500 feet of the proposed well location.

Attachments consist of annotated copies of the pinger, analog minisleeve exploder and side-scan sonar for lines 23 and 7 of the hazard survey.

cc: D. Balsinger J. Strasen D. Euddrus M. Neese (w/attachments) R. Hanna (w/attachments)

D. Harris R. Jantzen

971L/RH/mcw ATTACHMENT A

S O H I O P E T R O L E U M C O M P A N Y

TO: Ray Broussard Lafayette

DATE: January 9, 1986

FROM: Jack Golden

SUBJECT: Site Clearance - Viosca Knoll 990 (OCS-C-6899), Proposed "C" Location 10,840* FNL; 14,690' FEL; W.D. 1,295'

Gulf Coast Division Geophysicists conclude that no significant shallow d r i l l i n g hazards exist within 500 feet of the Viosca Knoll Block 990 proposed "C" well location (10,840' FNL, 14,690' FEL; W.D. 1,295').

The original records and summary report of a shallow hazard survey conducted by John E. Chance and Associates for Sohio Petroleum Company over Viosca Knoll Block 990 have been reviewed. We are in agreement with their tiadings and conclude that:

1) No obstructions are observed on the sea floor within 500 feet of the proposed location.

2) Seismic data indicate a thick sequence of parallel beds (over 1,000 feet) dip to the east. The rate of dip i s approximately 120 feet per mile.

3) No gas accumulations c" fauJts are observed at the proposed well location within the upper 1,000 feet below mudline (2,295 feet below sea level) or within 500 feet of the proposed well location.

Attachments consist of annotated copies of th- pinner, analog minisleeve exploder and side-scan sonar for lines 24 and 7 of the hazard survey.

Jack (Joluen

cc: D. Balslnger J. Strasen D. Buddrus M. Neese (w/attachments) R. Hanna (w/attachments)

D. Harris R. Jantzen

971L/RH/mcw

ATTACHMENT A

U.T.M. ZONE 16

BLK. 946

BLK. 989

Sohio Petroleum Compony O.C.S. - G - K899

BLK. 990

VIOSCA KNOLL AREA

BLK. 991

{NH 1 6 - 7

MISSISSIPPI CANYON AREA (NH 16 • 10) B L K . 2 8

VICINITY PLAT

SCALE

ATTACHMENT B-l

i PROPOSED MINERAL DEVELOPMENT

VIOSCA KNOLL AREA GULF OF MEXICO

APPLICATION BY SOHIO PETROLEUM COMPANY OCTOBER 9, 1984 LAFAYETTE, LOUISIANA

OCS-0 -61399

O B « c „ R T.D. -10,5CO

O RTO.-10,500'

LEGE N' D

O PROPOSED WELL LOCATIONS LOCATION "il". 9,8ft'tf FNL, I3,07d FEL LOCATION"C"' iU,340' FNL, 14,690'FEL

ATTACHMENT B-2 SCALS | « 2«000'

fit"**** iOMlO PETROLEUM COMPANY

OULF C04ST | OFFSHORE LOUISIANA

BLOCK 990 VI05CA KMOLL AREA

PROPOSED WELL LOCATIONS

" 8 " 0 "C"

«..»•• B IJQNN A hta»ia*l-M

AIR ' dAin 1 K'eVIEW FOR

tiOSCA XNOU AREA BLOCK 990 0CS-G-6S99

STANDARD OIL PROOUCTTON COMPAKV 3639 AMBASSADOR CAFFEKY PARKW.V LAFAYETTE, '.OU.*SIANA 70508

S»lf .tlTTED TO CARI KERLIN

RE'.HiLÂUK' SUPERVISOR

KAY I , 1986

PREPARED BY: JOHN E. CHANCE * ASSOCIATES, INC.

REGULATORY ANO ENVIRONMENTAL DIVISION LAFAYETTE, LOUISIANA PROJECT NO. W»-«083

John E. Chance 6 Assoc . , inc. -ATTACHMENT D

PROJECT'.'; .uP EMISSION SCHEDULE FOR EY01.ORATION PROJECT

I . Gr.,.eral Information

Location o" raci"! i ty - Viosca Knoll Area Block 990 Name of R'9/Platforn - Semi-submersible

Owner/Operator - Standard Oi 1 Production Company 3639 Ambassador "affery Parkway Lafayette, .ouisiana 70508

Contact Per;on - Cary Kerl in Regulatory Supervisor

P. j j e c t Start Date - January 1, 1987 Project End Oate - May 31, 1987

21,000 f*»et to be d r i l l ed 30 mi le: Offshore

I I . Total Emissions at Rig/Piatform. Dr i l l i ng (Year* 1 - 0)

Al1owabie Projected Emission Twitted Emissions Emissions Sta ti« s

p Substance (tons/yr) (tons/yr) (OK/N6)

1 CO 32826.64 14.38 OK

1 SO, c 999.00 .54 OK i ™* 999.00 91.99 OK VOC 999.00 4.91 OK •v. TSP 999.00 .05 OK

A. Transportation Emissions, Dr i l l i ng

Emitted Su osstance

C:ew Poat

(ton/yr)

Supply Boat

(tons/yr) Hel icopter

(tons/yr)

2

CO

SO

N0X

VOC

TS?

6.4«J

*

45.5i

2.45

•

5.E6

*

39.01

2.10

+

1.23

.04

.12

.11

.05

itehn E. Gh-iwe & Assort kv*

I I I . Transportation Servict* Pat©

Crew b.>at horsepower cf ?,500 Port V'jnfce, Louista".;-Waiting rime 4 hour(s) per t"*fjj 14 Tr*>(s) per Week

Supply boat horsepower cf 3,000 Port of Venice, Louisiana Waiting Time 10 hottr(s per t r i p 4 Trfp(s) per Week

Hel Icopters Po**t of Venice, Louisiana 1 Tr1p(s) per Wc-ik

IV. F'h^ngs of Air Quality Review

As per DOI-MMS regulations, this f a c i l i t y i s exempt from further a i r quality review LS i t has been determined that i t s operation w i l l not have a signif icant adverse environmental impact on a i r qual i fy .

V. Factors Used in Calcul ..MORS

A. Emission ^actors for Power Generation

Emitted Substance(s)

Dr i l l i ng (ib/hp-hr)

Production (ib/hp-hr')

CO .004200 .00084

so2 .001900 .00013 .028000 .0031

VOC .000550 .00031

TSP * .00011

Emission Factors for Transportation

Emitted Sub«stance(s)

Helicopters ("b/engine-LTO)

Boats Ob/gal)

CO 5.7000 .0598

x 2 .1800 *

™* .5700 .4196 VOC .5200 .0226

TSP .2500

. John E. €£- ftoe & Assoc., Inc.

".

DHT I fug Power Generation 60 hp-h ftt

Fuel Cor.sumption .0959 hp-hr / f t by Boats

if I . Methodology

Rfg/Piatfr.m - hurseoower-hour method Boats - horsepower-hour method Helicopte.s - lapding/takeoff (LTO) ryc le method

VH References

"Atmospheric rn-ss1ons from Offshore Oil Development ar.d ^ r o d i ^ o n " Dr i l l ing - EPA-450/3-77-026 (June 1977), pr. 81-92.

"C^npilat'on j f Ai r Pollutant Emission F e t o r s " . Boats, and helicopters - EPA Report AP-42 - (August 1977), 3rd Ec i t ion, pp. 116, 125, 1237.

* The EPA does not provide SO., and TSP emission factors for boats, nor

aces i t provide TSP emltslon factors for d^TMng.

- Job?; L Chance & Assoc., Inc. ^

SOHIO PETROLEUM COMPANY

DRILLING MUD COMPONENTS

Products of IMCO Services and Sun D r i l l i n g Products are l is ted in th is program for I l lus t ra t ion purposes. Equivalent or comparable products are available from other service companies such as NL Baroid, Magcobar, and Miichem.

Trade Name

IMCO GEL

IMCO SURLIFT

IMCO GELEX

IMCO LOYO

IMCO PLUG

IMCO MENTOR-28

IMCO RD-111

IMCO C-COR

IMCO X02

IMCO BAR

CAUSTIC SODA

IMCO LIG

SODA ASH

SUN LUBRA-GLIDE

SUN LUBRA-SEAL

Compos i t i on

Western Bentonite; A natural occuring element containing plates of S i l i ca a alumina ( Iner t )

Preshaped, wet processed, high density chrysot l le asbestos (a native calcium magnesium s i l i -cate)

Co-polymer of polyvinyl acetate & maleic anhydride

Pregelantlnized Starch

Crushed walnut hul ls

Mineral Oil

A proprietary blend containing modified l ignosulfonates, modified l i g n i t e and chromate

An organic f i lming amine

An Inorganic compound of the b i su l f i t e family

Mined bar i te (Ground barium sulfate)

Sodium hydroxide

L ign i te , ground a refined

Sodium carbonate

Stirene, divinalbenzene copolymer spheral beads

Mlcronlzed cal lulose f iber cotton seed hairs

Purpose

Primary wall bu i ld ing, f i l -trate control , a suspending agent for water based d r i l l i n g f l u i d

Viscosif ier fo r upperhole f lu ids

Bentonite extender

Fluid loss control

Lost c i rcu la t ion a b i t bal l ing

Lubricant/Fluid loss control

Thinner and f i l t r a t e control for water base d r i l l i n g f lu ids

Corrosion inh ib i to r and oxygen scavenger

Oxygen scavenger

Weighting agent

A lka l in i ty control

Thinner & water loss control

Removing hardness (calcium) from d r i l l i n g f l u i d

Reduces torque a drag

Improve wall cake

ATTACHMENT E