In iej> ly Rtftr Tor bS-2-2 SEP 14 1983

Gulf 011 Exploration and P, "ction Company

AtttnJon: Nr. R. L. Ntlntrt Poat Office Box ol590 Now Orleans, Louisiana 70161

Gentleman:

Reference is made to your Init ial Plan of Exploration ond Environmental Report received September 13, 1983, for Lease OCS-G 5631, Block 259, South Timbalier Area. This plan Includes the dri l l ing of five wells.

In accordance with 30 CFR 290,34, revised OeceOer 1979, and oer letter dated Jenuary 29, 1979, iMs plan has been determined to bn complete as of September 14, 1983, and 1s now being considered for approval.

Your plan control number 1s N-1320 and should be referenced In your ccwwunlca-tlon and correspondence concerning this plan.

Sincerely yours.

Original Signed John L Ward

^ 0. M. Solanas Regional Supervisor Offshore Operations Support

bcc: Leese OCS-G 5631 (OMS-2-3) '0MS-2-2 w/PubHc Info. Copy of the plan and ER

HHekmatdoost:gtj:«/14/83 Disk 3b

R9cor<is Mm

• • » . S - H o r v a t h

E n p l o r a t l o n Manager Nav Or laaaa Araa

P O Boa 61BOO Naw Oriaana. LA 701«1

September 12, 198p

/ f

LSD

Deputy Minerals Manager Offshore, Operations Support U. S. Department of the Interior Minerals Management Service Gulf of Mexico, OCS Region Post Office Box 7944 Metairie, LA 70010-7944

Dear S i r :

B t CfOtOCfCW sevrv

SEP 13 1983 urilUTlOfta sjwotr

CUtf flf MEXICO REGION MCTAMK, w.

Plan of Exploration Block 259, OCS-G-5631 South Timbalier Area Offshore, Louisiana

Gulf Oil Corporation plans to d r i l l 5 wildcat wells on the subject block. Tbe wells are A, B, C, D, and E.

Well "A" wi l l be a straight hole at site 4950' from the south line and 5950 f om the east line of the block. We proposed to begin work with the J. S orn No. 7 type rig between October 1 and December 31, 1983. As a dry hole the raeration should last about 200 days. As a producer about 245 days will le required.

Well "B" wi l l be a straight hole at site 4450' from the north line and 1200' from the east line of the block. As a dry hole the operation should last about 200 days. As a producer about 245 days should be required.

Well "C" wi l l be a straight hole at site 6400' from the north line and 500' from the east line of the block. As a dry hole the operation ahould last about 200 days. As a producer about 245 days should be required.

Well "D" w i l l be a straight hole at site 8550' from the north line and 1200' fron the east line of the block. Aa a dry hole the operation should last about 200 days. As a producer about 245 days should be required.

Well "E" w i l l be a straight hole at site 1550' from the eouth line 1200' from the east line of the block. As a dry hole the operation should last about 200 days. Aa a producer about 245 days should be required.

The rig w i l l be equipped and operated in compliance with OCS Order Nos. 2, 5, and 7. A l i s t of the drilling mud omponents and additives is included among the enclosures to this letter. Other enclosures illustrate the Opjfggigs of this test relative to the block lines and shoreline. a r i ageinent S

Manment

* O'vi»io* or out* On co»ao»*r.oN

D . p « y M i n . r . l . f U » U . r - 2 - September 12, 1983

Ir/site wi l l be about 67 miles from Leeville, La. Our operation wi l l be serviced by boats and helicopters using existing fac i l i t i e s at Morgan City and Leeville. The helicopters wi l l use the PHI heliports et Morgan City and Leeville. The boats wil l ut i l ize existing dock fac i l i t i e s maintained by Gulf. Our oi l s p i l l contingency plan I s on f i l e with your office. Gulf i s a member of Clean Gulf Associates (CGA). CGA maintains equipment at Grand I s l e , La. about 67 miles from this location. The response time within a 100 mile radius is 12 hours.

I f the test I s successful, l t v i l l be left with a buoyed casing stub covered by a protective dome. The stun w i l l facil itate the installation of a platform to accomodate surface producing equipment and possible additional dr i l l ing . Oil that may be discovered v i l l be bazged, at least in i t ia l ly . We wi l l seek a pipe­line connection for Gas. I f the well i s not a success i t wi l l be abandoned ac­cording to the terms of OCS Order Nos. 3. Any additional dri l l ing that ls pro­posed subsequent to this test w i l l be described by a nev plan.

Gulf has collected the data required by the notice to Lessees and Operators No. 75-8 (Dril l ing Hazards). These data are being forwarded to you under separate cover. An air emissions statement is also attached. We have evalua­ted the data and find no evidence of any shallow hazards to dri l l ing or any­thing of cultural or archaeological Interest. Please contact this office for any additional information you may require.

GULF OIL CORPORATION

Exploration Operations Manager

RF/RLM/ec

Enclosures:

Shoreline Veclnity Plat Location Plat List of Mud Additives Air Emission Data Rig Description Consistency Certification Anomaly Plat Site Clearance Letter for

Shallow Dri l l ing Hazards Environmental Report Public Notice Certification

SHORELINE VICINITY PLAT

SCALE I tl W II M 111

I I I I I I MILES

SOUTH TIMBALIER BLK. 259 BATHYMETRY MAP M M

0 6000 FEET

259

SOUTH TIMBALIER BLK. 259 LOCATION PLAT

O IOOO

DRILLING HUP COMPONENTS AWD ADDITIVES J

I

'i bentonite

Ben-ex

starch

Drispac

barite

defoamer

Desco

11 gno Sulfonate

clay !

floeculant and clay extender

non-fermenting

polyanionic celulose

barium sulphate

alcohol base

organic thinner

dispersive agent

Projected Air Emissions

Major Sources

Emissions In (lbs/day) tons per year

CO VOC NOx S0 2 * . TSP

Power onboard drilling vessel (Total footage drilled - 24,000' (26.33) 4.81 '9.73) 1.78 (121.66) 22.20 (8.09) 1.48 (8.68) 1.58

(1) Based on 60 hp hr/ft from Table 4-3, "Atmospheric Emissions from Offshore Oil and Gas Development and Production*, EPA No. 450/3-77-026, June 1977.

(2) Emission factors from Table 3.3.3-1, "Compilation of Air Pollutant Emission Factors", Third Edition, EPA Report AP-42, August, 1977.

Minor Sources

Includes helicopter landings and takeoff, one trip p;r day; supply and crew boats at dockside, one trip per day; fuel storage and transfer; loading and unloading operations; and incineration of waste paper (average 750 lbs/mo.) for duration of project of 1225 days.

Emission in tons/year

CO VOC NOx so 2 TSP

Minor Sources 5.60 1.20 2.90 0.70 0.50

Total a l l Sources 10.41 2.98 25.10 2.18 a 2.08

Emission Exemption (tons per year)

CO Exemption - E - 3400 D2/3; NOx, VOC, S02# TSP Exemption - E - 33.3 D

O - Distance from shore = 58 miles

CO E -50,945tons; NOx, VOC, S0 2 TSP E -1,931 tons

The projected air emissions during tbe drilling of the five proposed wells are considered below the exemption levels for each of the pollutants; hence no further air quality reviews ar_ indicated. Onshore Sources

No new fa c i l i t i e s will be installed at the onshore base.

I «

Rig Description

i J. Storm VII ; Marine Drilling Company

Thii Is a Bethlehem mat supported cantilever iackup drilling unit. The rig power ie mechanical. Three (3) Superior PTDS-8 diesels power the drawworks and rotary table. Two (2) General Motors EMD 12V-567 diesels mach drive a generator rated at 700 KW, three phase, 480 VAC. The mud pump system is driven by two (2) GMC EMD 16V-567 diesels.

Other equipment using diesel engines are two (2) Link-Belt ABS 138 cranes, each powtred by a GMC 6V-92N diesel engine and a Schlumberger Cyber Service wireline unit which is powered by a GMC 4-7IT diesel engine. A 150 KW, three phase, 480 VAC standby generator iw powered by a GMC 8V-71N.

Attached is schematic of this rig with a drawing of the surface diverter system for rig safety in accordance with OCS Order No. 2. A l i s t follows of the rig's blowout preventer system for safety and pollution prevention as required by OCS Orders 2 and 7.

1 - 20" Hydril, 2000 pei W? w/diverter spool

1 - 13-5/8" Hydril G.K., 5000 psi WP

4 - 13-5/8" 10,000 pel WP; 3 pipe rams and 1 blind ram; BOP's actuated with 2- 80 gal. 3000 psi accumulators with control console at driller's station and remote located

J STORM" 301

DEKCO SERIES 150

r I T I A I R - 0

BUITUFLY

DEKCO '"SlR IES II>0

-OPERATED

VALVE 1

12- AIR-OPERATED

BUTTERFLY VALVE 12" NOMINAL

^ Valve] i l l y Cpen

— 12" >*>iDyLL

N3TE: AIR-CP VALVES 70 BE CLOSED AS REODIRZD FOR KJ**?XND DIVERSION.

DTVLKJ LH LIKE ABCVT BELL NIPPLE

t<—< Hydraulic Acornulitor

I ? " N W W l — '

•pivixiu< c?rj Ticy pyrrnRS 1. At f i r s t f^gn of kick, pick up kelly Above 20"

Hydril. 2. 'Cpen any norniAlly closed valve in diverter line.

• dose BCP. 3. Divert any flew to down-wind side of rig by

closing Appropriate valve in diverter l ine.

8" Ncrninal

DEMCO SERIES BDO

8" rrDTuuuc B" Iterninal

KorjTAlIy Cpen

VTALVE RSttlKS CPEN AT ALL TIMES 20" x 3D" Swage

VALVE REMAINS CPD* AT ALL TIMES

: • • • 1 1 •

1*7'o" DERRICK

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MD3ILE DRILLING BARGE oV> SIDE ELEVATION :

DIMENSIONS OF PIATFORM i V ' M "i

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WIDTH AT COLUMNS-ISO*

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0 ' • •

f COASTAL ZONE MANAGEMENT

CONSISTENCY CERTIFICATION

Exploration Type of Plan

South Timbalier Black 259 Area and Block

OCS-G-5631 Cease Numoer

The proposed activit ies described 1n detail 1n this Plan conply with

L o u i s i a n a approved Coastal Managenent Program(s) and will be

conducted 1n a manner consistent with such Program(s).

G u l f o n F v p l n r a r i rm A, P ^ M p r i r n Company Lessee or operator

August 30, 1983 uate

Figure 4

ST 259/ 16

•». • H o r v t

August 29, J933

Exploration M«B«g«r N«* OTlatna Araa

P. O • e n 619BO N . w O r l e a n s . LA ? O l « 1

IOTl

It ineral Management Service 'Area Office for Operations Support P. 0. Box 7944.

'Metairie, Louisiana 70010 Attention: D. W. Solanas

Mineral Management Service Houma District P. 0. Box 10145 Houma, Louisiana 70361 Attention: Mr. John D. Borne

Re: Shallow Hazard Clearance from High Resolution Geophysical Data South Timbalier Are, Block 259 OCS-G - 5631, Wells A, B, C, D and E, Gulf of Mexico

Gentlemen:

Ve have reviewed the high resolution geophysical data in the vicinity of Gulf's five proposed wildcats on this lease and find that there are no shallow hazards at these locations.

WELL WATER DEPTH LOCATION

A 303 ft. 4950* FSL, 5950* FEL B 296 ft. 4450' FNL, 1200* FEL C 300.5 ft. 6400* FNL, 500* FEL D 304 f t . 8550* FNL. 1200' FEL E 316 ft. 1550* FSL, 1200' FEL

Although the contractor Interpretation Indicates location A to be within a sone of chaotic reflections, the digitally processed sparker data shows good bedding continuity to as deep as 500 milliseconds tvo way time or about 1400 ft. subsea.

Very truly yours,

W. H. Murphy \ —-V Technical Manager - Exploration

WHM:rm

A D i v i s i o n OF GULF OIL CO*»0»ATiON

- \

Environmental Report (Exploration)

for

South Timbalier Area Block 259, OCS G-5631

Lessee

Gulf Oil Exploration and Production Company

September 12, 1983

Contact Person:

Mr. L. R. Henry P. 0. Box 61590 New Orleans, LA 70161 (504) 569-3430

, . (2)1 DESCRIPTION OF PROPOSED ACTION

(a) TRAVEL MODES AND ROUTES j

Transportation of material, supplies and personnel between

South Ti^bklier Block 459 bases at Leeville and Morgan City,

Louisiana v i l l be by boat and helicopter. Boats from Leeville v.. j

terminal will travel to the d r i l l site via Bayou Lafourche outlet

through the Gulf of Mexico. Boats from the Morgan City terminal

will travel to the d r i l l site via the Atchafalaya River outlet

through the Gulf of Mexico to the d r i l l site. Helicopters will

generally travel the most direct route from PHIs bases at Leeville

and Morgan City to the d r i l l site, although weather conditions may

sometimes alter this route. Helicopter flights transferring crew

members to and from the d r i l l site will be done weekly. If severe

weather conditions prohibit these flights, the crews v i l l be trans­

ferred by cuv boats. Other service company and operator personnel

travel may require approximately 10 round trip flights of the heli­

copter (Bell 206 and 212 models) per veek. The supply boat v i l l

make daily runs from Leeville or Morgan City to the d r i l l site.

(b) SUPPORT BASE

The onshore support base for any proposed drilling operations

on Block 259 v i l l be from the existing Gulf dock at Leeville and

Morgan City, Louisiana. No enlargement or changes in these fa c i l i t i e s

v i l l be needed to accommodate the proposed drilling activity. Approxi­

mately 40 rig crev members, and supervisory personnel v i l l be required

on each seven day tour. In addition, about 25 other service company

people will be required diring the course of the drilling operation.

Radio dispatchers working on 12 hour shifts v i l l be located at

the shore bases. Other personnel located at each the shore base

- 1 -

include a shore basd supervisor and three transportation supervisors

to handle the loading and transfer of supplies and material onto

workboats for use at the d r i l l site. Workboats require a crew of

(c) NEW'SUPPORT FACILITY K. j

It Is not known if the proposed exploratory effort will

be productive of o i l and/or gas; however, i t would not be

expected that any additional expansion of the onshore base

would be needed in any event since the existing facility

i s not being operated at ful l capacity.

(d) DESCRIPTION OF NEW TECHNIQUES OR UNUSUAL TECHNOLOGY

There will not be any new techniques or unusual technology

required in carrying out the proposed drilling operation.

(«) MAP OF THE PROPOSED ACTIVITY WITH RESPECT TO STATE'S COASTAL ZONE

A shoreline vicinity plat showing the location of South

Timbalier Block 259 with respect to the coastline of the State

of Louisiana is attached. Also attached is a plat showing the

location of the d r i l l site within Block 259.

(f) FOR PLANS OF DEVELOPMENT/PRODUCTION, THE MEANS OF TRANSPORTATION

OF OIL AND GAS

The proposed activity Is to conduct an exploratory Investigation

for oil and gas. I f hydrocarbons are discovered, a development/

production plan w i l l be submitted at that time describing the

plans for transporting oil and gas to shore and to markets on the

mainland.

tours of 7 to 14 days

(3> DESCRIPTION OF THE AFFECTED ENVIRONMENT AND IMPACT

(a) PHYSICAL AND ENVIRONMENTAL

(1) Commercial Fishing

- 2 -

«

The lease site is' approximately 54 statute miles offshore

Louisiana in water depths ranging from 268' in the northwest corner

of the blodk to 324' in the southeast corner of the block.

Offsptjre Louisiana* ranked f i r s t in both commercial fish

landings and dollar value in 1979 in comparison with catches

from other states in the Gulf Region. The Louisiana parishes

(Lafourche and Terrebonne) adjacent to the d r i l l site harvested

approximately 47.7Z of the total shrimp harvest taken from a l l

of the Lousisiana coastal parishes in 1978. The Gulf fishery is

dominated by the shell fisheries; i.e., shrimp, crabs, and

oysters with small amounts of clam and scallops. The doi lai.'

value is twice that of the finfish harvest although the finfish

landings are much greater. The shrimp fishery in the Gulf includes

brown, white and pink shrimp and are taken almost exclusively by

trawl fishing in water depths from 6 to 250 feet. Smaller amounts

of sea bobs and royal reds from deep water are also taken (3Z).

These species of shrimp spawn in the open ocean and undergo A

series of larval phases in the plankton, followed by migration in

the post-larval phase to an estuarine nursery area, then return to

the ocean as adults.

The crab is also an important commerial fishery offshore

Louisiana. The blue crab makes up 98Z of the crab harvest for the

Gulf Region (Riley, 1970). Its l i f e cycle is similar to the shrimp

in that i t undergoes the planktonic, estuarlne, and open ocean

phases. Gravid females migrate to the open Gulf and release their

eggs in the spring and summer months. The adult crabs are found

in the estuarines and thus inland from the leased area.

- 3 -

The South Timbalier area is also an important commercial fish­

ing ground for finfish. Among the more important species off

Lafourche Parish coast include the red drum, black drum, sheephead,

Sea trout, both silver and white, are bottom fish in the Northern mm

Gulf and are usual ly taken by bottom trawls. Other important

species include red snapper and grouper which are taken by hook

and line in water depths from 5' to 1000'. The Atlantic croaker

i s an abundant f i shery in Lousisana's estuarine waters. The

Flor ida pompano i s an inshore f i s h taken in the surf or at passes

and is seasonally abundant from January to Apri l in shrimping areas.

The proposed d r i l l i n g operation may degrade the water quality

i n the immediate v i c in i ty of the d r i l l s i te temporarily due to

discharges of d r i l l mud and cuttings. Such a change in water

qual i ty may cause some species to avoid the area surrounding the

d r i l l site during this period while active d r i l l i n g operations

are underway. Once d r i l l i n g i s completed the population should

re turn to the area.

Some larvae and eggs of certa in species could als > ie adverse­

l y affected in the immediate area of the d r i l l s i te due to tem­

porary degradation of water qual i ty . This condition would be short

term and would not be expected to have any measurable effect on

any fishery.

The impact from the discharge of d r i l l cuttings would be to

smother sess i le benthic organisms in the area around the wel l .

The^e f i sh species are usually tiken ntc*r shore.

- 4 -

Studies have shown that these deposits are quickly re-colonized

(Zingula, 1975). Also, heavy solids contained in d r i l l mud dis-

charges may also be deposited on the bottom as a light coating

whiihl may have spine temporary adverse effect. These areas appar­

ently* are quickly repopulated indicating no persistant toxicity of

the mud sediments. (Reigh et a l , 1980; Gilbillau et al, 1980)

An oil s p i l l could also cause water quality degradation due

to the introduction of possible toxins into the water column.

Most adult fish, however, would probably avoid such areas and

no significant or persistent direct effect on fish population

would be expected. Any s p i l l would be subject to immediate con­

tainment and clean-up. Oil sp i l l s have a low probability of

occurring during exploratory drilling. (Dannenberger, 1976)

(2) Shipping

There are no designated shipping safety fairway or anchorage

area crossing or located within South Timbalier Block 259. (U.S.D.I.,

FREIS, 1983, Visual No. 11)

(3) Small Craft Pleasure Boating, Sport Fishing, and Recreation

Studies have shown that fish which would normally be scattered

throughout large areas are often concentrated in small areas

surrounding petroleum platforms and are attracted by the food

and shelter which the structure offers. Many of the fish species

that congregate around petroleum structures are prime sport fishing

targets including snapper, grouper, mackerels, cobia, etc. I t is

believed, too, the new a r t i f i c i a l reefs have l i t t l e , i f any,

effect on the carrying capacity or the size distribution of fish

on the natural reefs (Stone - 1979). It could, therefore, be

- 5 -

assumed -that the qulality and quantity of offshore fishing would

be further enhanced by any increase in petroleum structures on the

Mexico Pishery Management Council (G.M.F.M.C) recently published

data indicating that red snapper stocks were on the decline and

ihis condition was possibly due to over fishing by the recreational

fisher (1980 b). The GMFMC report suggested the possiblity, too,

that the apparent decline in snapper population may not be a real

one but rather the population spread out over greater areas due to

increasing numbers at platforms being installed. According to the

report, natural reef fishing habitat in the Gulf provides approximately 2

39,000 KM . The habitat provided by 2,000 petroleum platforms,

assuming an area of 50 meters by 50 meters each, would provide

another 5,000 KM2 of habitat.

(4) Cultural Resources

S.uth Timbalier Block 259 is located approximately 21 miles

seaward of the line marking the outer limits of the zones

designated as "high probably lines for prehistoric and historic

cultural resources" (U.S.D.I., FREIS, 1983, Visual 11) and, as

such, the requirements of Lease stipulation No. 1 were not invoked

as being applicable to the block (Letter to the Lessees by MMS,

Gulf of Mexico Region, July, 1983). Ti:e side scan sonar and magneto­

meter interpretation indicated many very small depressions or pock-

marks, particularly in the south half of the block. No magnetic

anomalies were observed in the block (Recal Geophysics, 1983).

OCS. As> a result, thes'. structures provide both sport and commercial

abundant fish population*. The Gulf of

- 6 -

I

The most widely accepted theory advanced as a cause for these pock-

marks is tfiat they are due to the removal of surface sediments by

the upward' flow of gas or liquids i n which the sediments were swept i

away b> f>o|ttom currents. (King and MeLean, 1970). No active seeps

were detected in the water column above these features.

(5) Ecological Sensitive Features

There are no biologically sensitive features or areas of

particular concern i n the project area. The closest designated

b i o l o g i c a l l y sensitve area (Diaphus Bank) is approximately 32

miles to the southwest. (U.S.D.I., FREIS, 1983, Visual No. 10)

A l l the coastal area of Louisiana has been included in the

state's coastal zone management plan. As such, any proposed OCS

a c t i v i t y must be reviewed by the state's CZM authorities and, as

provided by Federal law, such a c t i v i t y must be consistant with

the state's management plan before a permit for the project can be

issued hy the responsible Federal agency.

(6) Existing Pipeline and Cables

There are no pipelines or no known cables crossing the project

area. (U.S.D.I., FREIS, 1983, Visual No. 7)

(7) Other Mineral Uses

There are no known miner. 1 resources on Block 259 other than

possible o i l and gas deposits.

(8) Ocean Dumping A c t i v i t i e s

The leased area i s not located within any EPA designated ocean

dumping site or any interim dumping sit e that has been so designated

by EPA. (U.S.D.I., FREIS, 1983, Visual No. 11).

(9) Endangered or Threaten Species

Seven species of marine mammals that have been sighted i n the

Gulf of Mexico have been c l a s s i f i e d as endangered species (Federal i

Regisjt^r, 1975). "'. Tfrese are the sperm whale, r i g h t whale, humpback

s e i whale, f i n whale, blue whale, and the West Indian manatee.

Five species of marine t u r t l e s that occur i n the Gulf area are

also on the endangered or threatened species l i s t . These are the

loggerhead, green, A t l a n t i c r i d l e y , hawksbill, and the leatherback.

According to Hildebrand, a major feeding area f o r the A t l a n t i c

r i d l e y may be o f f the Louisiana coast and reports have indicated

t h a t portunid crab com^ricis a large p o r t i o n of the diet of the

specimen examined. Except f o r reported occasional nesting along the

southern Texas coast, t h i s species nests e n t i r e l y along a 14 mile

s t r e t c ' i of the Mexican coast near Tamaulipas, Mexico. The number

of nesting females has declined from over 40,000 i n the 1940's to

about 400 - 500 i n 1976 and the species is t r u l y an endangered one.

The le.-therbac^, also l i s t e d as an endangered species,

ran *.cughout the Gulf of Mexico and western North A t l a n t i c

as f a r north as Nova Scotia. The species has also been observed i n

inshor waters during c e r t a i n periods of the year i n areas where

j e l l y f i h are found i n abundance, presumably which they f o l l o w and

feed upon.

Any impact of th*. proposed a c t i v i t y on marine mammals and

t u r t l e s cannot be accurately assessed but would appear to be somewhat

dependent upon the p r o b a b i l i t y of an o i l s p i l l , the population size

and d i s t r i b u t i o n of the species, as well as the size and l o c a t i o n of

the sea impacted by the s p i l l e d o i l . Recent studies, however, have

- 8 -

indicated that oil remaining on a beach for one year after a spill

did not significantly affect mortality of sea turtle eggs. The

effect of petroleum on the development and survival of turtle embryos

is s t i l l iicbnclusive,'a^though fresh o i l on top of the sand may cause

(b) SOCIQ-ZCONOMIC

No new personnel or other significant changes that might other­

wise affect the coastal communities are contemplated by the proposed

exploration effort.

Most of fhe unavoidable adverse impacts are of a temporary

nature and the environment should be completely restored soon after

drilling operations have ceased. Discharges of d r i l l mud and cuttings

may cause some water quality degradation while drilling. Similarly,

the deposition of d r i l l cuttings on the ocean floor could smother

sessile benthic organisms but these, LOO, should quickly re-colonize.

Air quality will be temporarily degraded due to emissions from the

exhaust of diesel engines and possibly hydrocarbon vapors from

diesel storage tanks. Any hydrocarbons vented to the atmosphere

while testing the well may also cause some degradation of air

quality. Any blowout of a well which caught fire may also

introduce into the atmosphere large amounts of carbon particulates,

and other pollutants such as oxides of sulphur and nitrogen. In

most cases, such a condition would be dissipated rather quickly by

climatic conditions ard would not seriously impair air quality at

the shoreline.

can be expected within the foreseeable future.

incubating sea turtle eggs.

(4) UNAVOIDABLE ADVERSE IMPACT

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Because of. the c r i t i c a l need to develop new energy reserves for

the economy and securi ty of the United States, the proposed ac t iv i ty

should be implemented without Jelay. No new feasible technology that

wouljdjtend to mfrtigate these minimal and temporary adverse impacts

can be expected within the foreseeable future.

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(5) REFERENCES

Recal Geophysics, Incorporated, July, 1983, A High Resolution Geophysical Survey of South Timbalier Block 259, Houston, TX.

nenberger, E. P., 1976, Oil Spills, 1971 - 1975, Gulf of Mexico Outer Continental Shelf, Geological Survey

United States Department of the interior, Bureau of Land Management, and Minerals Management Service, Various, Final Environmental Impact Statement, Outer Continental Shelf Oil and Gas Lease Sale

United Stated Department of Commerce, 1980, Final Environmen il Impact Statement for Louisiana Coastal Resources Program, Office of Coastal Zone Management, Washington, D.C.

(6) STATEMENT

The proposed activity 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 a l l applicable re­

quirements for equipment types, general project layout, safety

systems, and equipment and monitoring systems.

(2) All operations will be covered by an MMS approved oil s p i l l

contingency plan.

(3) All applicable Federal, State, and Local requirements regard­

ing air emissons and water quality and discharge for the proposed

activities, as well as any other permit conditions, will be complied

with.

COASTAL ZONE MANAGEMENT

CONSISTENCY CERTIFICATION

Exploration * Type of Plan

!

South Timbalier Area, Block 259 Area and Block

OCS G-5631 Lease Number

The proposed a c t i v i t i e s described in deta i l in th is Plan comply with

Louisiana approved Coastal Management Program! s) and w i l l be conducted

in a manner consistent with such Program(s).

Arrangements have been made with the State-Times in Baton Rouge,

Louisiana to publish a public notice of the p cposed Act iv i t i e s no

later than September 15, 1983.

G u l f O i l E x p l o r a t i o n and P r o d u c t i o n Company Lessee or Operat:>r

R. F. Thomas Certifying 61Flciml

September 12 . 1983 Date

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"lenient