# Project No. 1106-1257b SECTION 3

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# Seafloor Furrows. Dense seafloor furrows are present in the s outheastern portion of the Cascade area. The

furrows are evident in the multi-b eam data as linear features trending parallel to the Escarpment (see Map 4a). In general individual furrows average about 100 ft wide and 30 ft deep and have relatively steeply dipping walls. The furrows are tightly spaced, averaging between 75 and 100 ft apart.

10 ms

~25 ft 1,000 ft

Seafloor Furrows

Seafloor Flukes

T R

I P L

E T 

### 10 ms

~25 ft 1,000 ft

Seafloor Furrows

Seafloor Flukes

T R

I P L

E T



# Figure 15. Subbottom profiler line 138 shows the transiti on between “fluked” and “furrowed” seafloor.



# The right of the figure illustrates the subbottom profiler expression of the furrows while the left side of the figure illustrates the flukes. The fu rrows incise into the otherwise undisturbed stratigraphic section. They are amorphous on the profiler as they act as closely-nested point sources that attenuate the profiler signal creating beam spreading and focusing. This is fu rther expressed by the interference evident in the otherwise parallel and continuous st ratigraphy below the furrows. The side-scan data show a striped seafloor of alternating light and dark areas illustrati ng the shadowing effect produced by regularly spaced, parallel linear furrows (see Map 7A). The soil properties are presented in Figure 16 below.

A number of box core and short piston core samples were recovered from this region. Typically the piston core samples were less than 20 ft in length. Table 1 lists the cores recovered from the furrowed region of the UCR province. Results of the standard geotec hnical testing are shown in Figure 16 with a more detailed presentation of results in Appendix B.

Piston Core Box Core

CPC-1 and CPC-1R CBOX-1

CPC-2 and CPC-2R CBOX-2

CPC-3 CBOX-3

CPC-4 CBOX-4

CPC-10 CEXP1-BOX1

CPC-14 CEXP1-BOX2

CPC-15 CEXP1-BOX3

CPC-16 CEXP2-BOX1

CEXP1-PC1 CEXP2-BOX2

CEXP1-PC2 CEXP2-BOX3

CEXP2-PC-1

CEXP2-PC-2

Table 7. List of cores for the seafloor furrows of the UCR province. 

# PROPRIETARY

# Project No. 1106-1257b SECTION 3

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### Sensitivity

0 500 100 200 300 400 

### MV Shear Strength (psf)

0 2.5 0.5 1 1.5 2 

### Liquidity Index (LI)

0 200 40 80 120 160 

### Moisture Content (%)

20 0

18 16 14 12 10 8 6 4 2Penetration below Seafloor(ft)



# Figure 16. Geotechnical test results for the seafloor furrows of the UCR province



# The near surface soils within this area are generally ve ry soft, highly plastic, normally consolidated clays. The soils are fairly uniform over this region of the province as is expected from soils that have been differentially eroded and slightly scoured due to cu rrents. There is excellent correlation between the geologic observations and th e ground-truth soils data.

As can be seen in Figure 16, the moisture conten t data follows a decreasing trend from generally over 120% at the seafloor to about 80% at 18 ft. The LI also decreases with depth. Shear strength was measured with miniature vane testing and fall with in a narrow range that increases with depth. The strength of the surficial sediments varies between 25 and 75 psf increasing to 150 to 200 psf at 18-ft penetration. Soil sensitivity generally ranges between 2 and 4. Figure 16 does show occasional sensitivity results below 2 indicating some sample disturbance at depth. In general, the sample quality was good.

Future facilities planned for this region of the U CR include one FPSO mooring cluster and the potential Gas Export Option 2 pipeline. The final selection of th e pipeline route has yet to be determined and may

never occur. The conditions in Seafloor Furrows area of the UCR are favorable for FPSO clusters and pipeline installation and performance. Attention s hould be given to the placement of the individual moorings with respect to the crests and troughs of the furrows.

Seafloor Flukes. An area of seafloor flukes is observed between the Escarpment and the furrowed region. Individual flukes are about 150 to 200 ft in length and can be up to 10 ft in height, but more typically average between 5 and 8 ft high. The flukes are randomly distributed but do tend to cluster in linear to sublinear grouping perpendicular to the Escarpment and the northeasterly to southeasterly direction of current

flow.

The current velocity is thought to be stronger in fl uked regions relative to furrowed regions. This arises from observations of bedforms gene rated in marine clays in flume tests (Allen, 1950). The increase in current velocity in this area may arise from a je t effect as the currents compress around a bend in the Escarpment to the north. The subbottom profiler data in Figure 15 shows ~ 20ft of the shallow stratigraphic section has been removed from this region exposing olde r, presumably stiffer clays at the seafloor. The side-scan sonar data show a mottled appearance indica ting a high variability in strength or composition of

surficial sediments. Darker areas on the side-scan mosaic (Map 7A) indicate areas where erosion has exposed sediments down to the level of the Triplet. 

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# Several box cores and short piston core samples were recovered from the seafloor flukes area of the UCR province (see Table ). Typically the piston core recove ry was about 15 to 18 ft in length. Results of the standard geotechnical testing are shown in Figure 17 with a more detailed presentation in Appendix B.

Piston Core Box Core

CPC-5 and CPC-5R CBOX-5

CPC-6 CBOX-6

CPC-7 CBOX-7

CPC-9 CEXP1-BOX4

CPC-10 CEXP1-BOX5

CPC-12 CEXP1-BOX6

CPC-13 CEXP1-BOX7

CEXP1-PC3 CEXP1-BOX11

CEXP1-PC4 CEXP1-BOX13

CEXP1-PC8 CEXP1-BOX14

CEXP1-PC9 CEXP1-BOX15

CEXP1-BOX16

Table 8. List of cores for seafloor flukes of the UCR province.

0 6 12345



### Sensitivity

0 500 100 200 300 400 

### MV Shear Strength (psf)

0 2.5 0.5 1 1.5 2 

### Liquidity Index (LI)

0 200 40 80 120 160 

### Moisture Content (%)

20 0

18 16 14 12 10 8 6 4 2Penetration below Seafloor(ft)



# Figure 17. Geotechnical test results fo r seafloor flukes of the UCR province.



# The soils in this area are very soft to soft, highly plas tic, normally consolidated clays. The soils are fairly uniform over the province as is expected from soils that have been differentially eroded due to currents. The geotechnical data correlates well with the geologi c observations from the AUV and 3D-seismic data of erosion and exposure of older, stronger strata.

The moisture content and LI results tend to d ecrease with depth corresponding to the increasing shear strength. The measured shear strengths for this sub-pr ovince are very similar, but slightly higher than the furrowed area of the UCR. The surficial strength of the fluked sediments ranges from 25 to 100 psf and increases to 150 to 300 psf at 18-ft depth. Soil sensitivity ranges from 2 to 5 indicating good sample quality with little sample disturbance.

Future facilities planned for this region of the UCR in clude the FPSO, riser bases, two mooring clusters and

the East Drill Centers and infield flowlines. The conditions in seafloor flukes area of the UCR are favorable for installation and performance of these fac ilities. Attention should be given to the locally 

# PROPRIETARY

# Project No. 1106-1257b SECTION 3

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# increased gradients on the sides of the flukes and the periodically intense seafloor currents resulting in the

erosion and formation of the flukes.

Seafloor Flukes and Furrows. Seafloor flukes with furrows superim posed on them are evident at the base of the Escarpment. This “furrowed flukes” region is more extensive along the base of the Escarpment in the south of the Cascade area, extending out from the E scarpment about 3.5 miles, while, to the north the region thins, limited to the seafloor within about 2,000 ft of the Escarpment. The furrows in this region are similarly formed as the furrow in th e southeastern “furrowed” region; however, their appearance is quite different. In the multibeam data, the furrows are ob served as linear features trending sub-parallel with the Escarpment in the south and merging with the Escarpmen t in the north. A hypothesis is that this is a transitional current velocity zone with slightly lowe r current velocities in the shadow of the bend in the Escarpment to the north.

A combination of thrust fault related uplift, lo cal slump deposition derived from the Escarpment, and seafloor erosion result in a high degree of variability in seafloor soils and shallow stratigraphy. Dark, subcircular areas seen in the side-scan data indicat e slump derived debris aprons extending up to approximately one mile out from the Escarpment (Map 7A). Linear, dark and light striping in the side-scan records can represent variable soils exposed along th e walls and floors of furrows; however, it may also represent the shadowing effect of the furrows. Thrust faulting at the toe of the Escarpment has uplifted and exposed older strata which, further from the Escarpm ent’s base, become buried in areas by slide deposits derived from the Escarpment.

The soils within the Seafloor Furrowed Flukes area of the UCR province was sampled with the box corer and short piston corer (see Table for listing). Typically the piston core samples were less than 20 ft in length. Results of the standard geotechnical t esting are shown in Figure 18 with a more detailed presentation in Appendix B.

Piston Core Box Core

CPC-8 CBOX-8

CPC-11 and CPC-11R CEXP2-BOX4

C-ESC-PC-1

C-ESC-PC-10 and C-ESC-PC-10R

Table 9. List of cores for the seafloor furrowed flukes region of the UCR province.

0 6 12345



### Sensitivity

0 1000 200 400 600 800 

### MV Shear Strength (psf)

0 2.5 0.5 1 1.5 2 

### Liquidity Index (LI)

0 200 40 80 120 160 

### Moisture Content (%)

20 0

18 16 14 12 10 8 6 4 2Penetration below Seafloor(ft)



# Figure 18. Geotechnical test results for the se afloor furrowed flukes region of the UCR province. 

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# Project No. 1106-1257b SECTION 3

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# The soils in this area are very soft to soft, highly pl astic, normally to slightly overconsolidated clays. The soils within this area, as expected, are similar to t hose observed in the two other areas of the UCR province, except where encountering a local slide deposit or exposur e of stronger stratigraphy above the thrust front. There is excellent correlation between the geol ogic observations and the ground-truth soils data.

The moisture content and LI results, presented in Figur e 18, show a general decreasing trend with depth. The strength of the surficial sediments varies betw een 75 and 150 psf and increases with depth to about 300 psf at 17 ft. Two cores (C-ESC-PC1 and E-ESC-PC10R ) have a shear strength peak at ~9 ft. This is likely to arise from either encountering a shallow-burie d debris flow or stronger soils related to uplifted strata above the thrust front. Soil sensitivity results are generally between 2 and 4. Figure 18 does show occasional sensitivity results below 2 indicating some dist urbance, due either to sampling or possibly slide deposits.

The West Drill Center is the only future facility pla nned for this region of the UCR. The geologic and geotechnical conditions observed appear to be favorable for placement of this facility.

Topographic Low. A ridge, with approximately 50 ft of seabed relief, is located along the southwestern edge of the Cascade area (Maps 2A and 4A). The ridge represents the northern limit of a topographic low which extends southward out of the survey area. The low is possibly the now-filled remnant of a paleochannel that focused mass transport events coming from above, or on, the Escarpment. The flukes and furrows are present within the low; however, their effect on the seafloor is less pronounced than it is in the “furrowed” and “fluked” regions to the north.

The subbottom profiler data, shown in Figure 19 below, shows a series of shallow anticlines in the shallow subsurface. Mass-transport deposits underlie the dr ape within synclines between the anticlines and older strata, down to the Triplet in places, are exposed acr oss the crests of the anticlines at the seafloor. These outcrops are evident as darker areas in the side-scan mosaic (Map 7A). The anticlines likely arise from dewatering of the larger, deeper slide deposits and differential compaction of the overlying stratigraphic

section.

# Project No. 1106-1257b SECTION 3

- 27 - Figure 19. The subbottom profiler data within the topographic low show folded strata in the shallow subsurface. Darker region s on the side-scan mosaic (Maps 1C-4C) indicate areas where the “Triplet” outcrops.



# No shallow piston core or box core samples were specifi cally taken in the area. However, the soils are expected to be consistent with those observed for th e Seafloor Furrowed Flukes area of the UCR province. A composite of soil properties for the UCR province is presented in Figure 20 to provide a general range of expected properties for the Topographic Low sub-province.

0 6 12345



### Sensitivity

0 500 100 200 300 400 

### MV Shear Strength (psf)

0 2.5 0.5 1 1.5 2 

### Liquidity Index (LI)

0 200 40 80 120 160 

### Moisture Content (%)

20 0

18 16 14 12 10 8 6 4 2Penetration below Seafloor(ft)



# Figure 20. Composite soil information to estimate condi tions for the Topographic Low region of the UCR province.



# As mentioned above mass-transport sediments underlie the drape within the synclines and the older strata in this area. A Jumbo Piston Coring program was recently completed that sampled this area. The JPC core 10 ms

~25 ft 1,000 ft

TRIPLET

ANTICLINES OUTCROPS OF THE “ TRIPLET ” COORESPOND TO DARKER

AREAS ON THE SIDE

- SCAN MOSAIC (MAP X) 

# 10 ms

~25 ft 1,000 ft

TRIPLET

ANTICLINES OUTCROPS OF THE “ TRIPLET ” COORESPOND TO DARKER

AREAS ON THE SIDE

- SCAN MOSAIC (MAP 7A)



# PROPRIETARY

PROPRIETARY

# Project No. 1106-1257b SECTION 3

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# is undergoing laboratory testing. In addition to the JPC program, a soil boring and PCPT program have recently been completed for this area.

Future facilities planned for this region include an FPSO mooring cluster. We believe the conditions will prove to be favorable for placement of the mooring. Consideration should be given to the potential for soil variability until the results from the additional geotec hnical programs mentioned above are available. These additional data will subsequently be integrated to further assist in facilities layout and foundation engineering.



# Chemosynthetic Communities

LCS Province. Several mound features, possible gas expulsion mounds, are identified in WR 160 as shown on Map 8A and in Figure 21.

10 ms

~25 ft 1,000 ft

Expulsion Mounds



## TRIPLETBlanking 

## 10 ms

~25 ft 1,000 ft

Expulsion Mounds



## TRIPLETBlanking



# Figure 21. Subbottom profiler line 117 sh owing mounds in the LCS province.



# The mounds are potentially favorable locations for ch emosynthetic communities to exist. The planned Cascade field development will not impact this area as the entire development is below the Escarpment on the Upper Continental Rise. Darker regions of the side-scan sonar mosaic (Map 7A) correspond with outcrops of the Triplet. There does not appear to be any other locations, away from the mounds, in this province which could support significant, high density chemosynthetic communities. The potential Gas Export Option 2 route is over a mile to the south-southwest from this area.

SE Province. The Escarpment is heavily faulted and most of the faults are salt rooted. The possibility for migration of fluids along these faults to the seafloor exis ts. It is difficult to distinguish, in the side-scan mosaic (Map 7A) areas of potential chemosynthetic co mmunities from outcrops of older, firmer strata as both will display a darker texture in the mosaic. Previous ROV studies have observed very local, small, dense chemosynthetic communities on the steep slopes of the Escarpment. The Cascade infield facilities layout does not get near the Escarpment. Howeve r, the potential Gas Export Option 2 route crosses the Escarpment and potential future MODU anchors are laid out to fall on the Escarpment. When necessary, to place subsea architecture on the Escarpment, operators in the past have selected to perform site specific ROV investigations to confirm the sites are clear.

UCR Province. There does not appear to be any areas of significant, high density chemosynthetic communities in this province, nor areas that have conditions conducive to supporting those communities. Seafloor currents have, and continue to, erode and re deposit the seabed sediments throughout this province. 

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# Project No. 1106-1257b SECTION 3

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# Therefore, it is unlikely that organisms would find su itable locations with the necessary firm substrate to anchor themselves to the seabed. Additionally, there does not appear, in the geophysical or geotechnical data, to be shallow gas or active venting of fluids to th e seafloor in this province. The darker regions of the side-scan mosaic (Map 7A) correspond to areas where the Triplet outcrops. The proposed Cascade field layout is entirely on the UCR and should not encounter or be constrained by chemosynthetic organisms.

# Project No. 1106-1257b SECTION 4

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# SECTION 4: SHALLOW GEOLOGIC CONDITIONS IN THE

CHINOOK DEVELOPMENT AREA

Petrobras America Inc. (PAI) is evaluating development of the Chinook area in Walker Ridge Area (WR) in the Gulf of Mexico. PAI has proposed placing a subsea drill center in Block 425 and tie-back flowlines extending from the drill center to the Cascad e FPSO (Section 3). The area surveyed for the Chinook Development area includes WR Blocks 425, 426, 469, and 470 (Map 1B).



# Bathymetry and Seafloor Gradient

Water depths in the Chinook Development area ra nge from 8,607 ft in the northwestern corner of WR 425 to 9,260 ft in the southeastern corner of WR 470 (Map 2B). Water depths increase relatively uniformly across the area from northwest to southeast. An exception to this is in central WR 426 and northeastern WR 470 where water depths increase into a topographic low (Map 2B).

Seafloor gradients range from nearly 0o over much of the southwestern two-thirds of the area to locally 50° along the walls of furrows in the northeastern third of th e area (Map 3B). Seafloor gradients up to about 6°

are common in the southeastern third of the area associ ated with seafloor anti-dunes. A discussion of these features is presented later in this section.



# Physiographic Province, Seafloor Morphology, and Stratigraphy

The Chinook Development area is located on the Upper Continental Rise (UCR) approximately 12 miles south-southeast of the Sigsbee Escarpment (see Figure 3). The area exists entirely within the UCR province as defined in Section 3 of this report. The following three sub-provinces, as shown in Figure 22

have been identified within the Chinook area based on th e occurrence of seafloor features: (UCR) Seafloor Furrows; (UCR) Seafloor Anti-Dunes; and (UCR) Topographic Low.

WR

425 WR

426

WR

469 WR

470 

# SEAFLOOR FURROWS

SEAFLOOR ANTI SEAFLOOR ANTI

- DUNES T O

P O

G

R

A

P

H

I C

L O

W T O

P O

G

R

A

PH

I C

L O

W 

## WR

425 WR

426

WR

469 WR

470 

# SEAFLOOR FURROWS

SEAFLOOR ANTI SEAFLOOR ANTI

- DUNES T O

P O

G

R

A

P

H

I C

L O

W T O

P O

G

R

A

PH

I C

L O

W



### CHINOOK

DRILL

CENTER CHINOOK

TiE-BACK

ROUTES



# Figure 22. Physiographic sub-provinces within the Chinook Development area.

# Project No. 1106-1257b SECTION 4

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# (UCR) Seafloor Furrows

. Seafloor furrows are present in the northern portion of the area (WR 425 and 426) as shown in Figure 23 below and on Map 4B.

10 ms
~25 ft 1,000 ft

Seafloor Furrows



## TRIPLET



# Figure 23. Subbottom profiler line 641 showing seafloor furrows in the Chinook area.



# The seismic stratigraphy is composed primarily of parallel and continuous reflectors. The image above

illustrates the incisive nature of the furrows into existing parallel stratigraphy. As observed at Cascade, there is some attenuation and focusing of the profiler en ergy in the tightly spaced, very steep furrows. The “Triplet” is mapped in the Chinook area, Map 5B show s depths bml to the base of the transitional late Pleistocene (low-stand) and current Holocene (high-stand) sediments.

The furrows are evident in the multi- beam data as linear features trending northeast to southwest (Map 4B). In general, individual furrows average about 100 ft wi de and 30 ft deep and have relatively steeply dipping

walls. In the northwestern corner of WR 425 the furrows are more tightly spaced, often with less than 25 ft between them. Further to the southeast (in the central portion of WR 425) the furrows become more spread out, up to 200 ft apart. These furrows also appear to branch and merge with each other. The exact nature of the seafloor current responsible for the varying appearance of the furrows in this area is not well understood at this time; however, it is possible that th e dominant direction and/or intensity of the currents may vary over time (Maps 2B and 4B).

The side-scan data show a striped seafloor of altern ating light and dark areas (Map 6B). Soils will be similar to those observed in the furrowed sub-provi nce at Cascade, varying from normally consolidated clays in the areas between the furrows to stiffer, slightly over-consolidated clays, silts, and possible foraminiferal sands along the furrow floors.

The Chinook Tie-Back routes will cross the furrowed area as they traverse north-northeast to the Cascade FPSO (see Figure 22). The routes appear feasible give n the observed geologic and geotechnical conditions. The topography of the furrows, and seafloor currents that cause them, should be considered with respect to the route engineering.

(UCR) Seafloor Anti-Dunes. The remaining portions of the Chinook area, which are free of furrows, contain seafloor anti-dunes (Figures 24 and 25 and Ma p 4B). Anti-dunes are defined as low, undulating bedforms whose crests are in phase with the seafloor cu rrents; therefore, they migrate by accretion in the upstream direction. The anti-dunes in the Chinook area are typically 2 to 5 ft in height and spaced about 500 to 700 ft apart. They are randomly distributed, but do seem to become less prominent on the seafloor in the southwestern portion of the area. The side-scan data in this region displays a mottled appearance (Map 4B), with lighter areas indicating where anti-dunes are located. 

# PROPRIETARY

# Project No. 1106-1257b SECTION 4

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# The subbottom data show parallel and continuous reflectors in the shallow stratigraphy beneath this region as shown in Figure 24 below.

10 ms

~25 ft 1,000 ft

T

R

I P

L

E

T Seafloor Anti-Dunes Offset 160 ft NW

JPC-9

54.33 ft Offset 45 ft NW

CPC-4

16.17 ft 

# 10 ms

~25 ft 1,000 ft

T

R

I P

L

E

T Seafloor Anti-Dunes Offset 160 ft NW

JPC-9

54.33 ft Offset 45 ft NW

CPC-4

16.17 ft



# Figure 24. Subbottom profiler line 641 showing seafloor anti-dunes in the Chin ook Development Area.



# A series of low anticlines exist in the southern portions of the WR 469 and 470 shown below in Figure 25.

Figure 25. Subbottom profiler line 725 show ing anticlines in WR 469 and 470.



# The folds are approximately 30 ft in height and roughly 5,000 ft between crests. These folds affect the seafloor and shallow stratigraphy evenly to the limit of the subbottom data. The cause of this deformation is not evident in the data. It is possible these feat ures are related to compaction of large, regional masstransport deposits deeper in the stratigraphic section.

The Chinook Drill center and southern end of the Chinook Tie-Back routes will be in this sub-province (see Figure 22). The geologic and geotechnical conditions are favorable for these facilities. The currents should be considered with respect to the development engineering.

(UCR) Topographic Low. A topographic low with a maximum of 140 ft of seabed relief is located in the central portion of WR 426 (Maps 2B and 4B). This low is a continuation of the topographic low discussed in Section 3 of this report. Figure 26 on the next page is an annotated subbo ttom profiler of this subprovince. 10 ms

~25 ft 1,000 ft

TRIPLET 

# 10 ms

~25 ft 1,000 ft

TRIPLET 

# Seafloor Anti-Dune 

# PROPRIETARY

# Project No. 1106-1257b SECTION 4

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# 10 ms

~25 ft 1,000 ft Seafloor Furrows

Seafloor Anti-Dune within the Topographic Low



### T

RI

P

L

E

T 

# 10 ms

~25 ft 1,000 ft Seafloor Furrows

Seafloor Anti-Dune within the Topographic Low



### T

RI

P

L

E

T



# Figure 26. Subbottom profiler line 720 showing th e topographic low in the Chinook area.



# The figure shows a series of low folds or anticlines in th e shallow subsurface. As with Cascade, the feature may be the shallow expression of a deeper paleo-cha nnel that focused both regional mass-transport deposits and landslides emanating from the Escarpment to the north and east of the Chinook area.

The near-surface sedimentary section (above the triplet, Map 5B) thickens, by approximately 10 to 15 ft within the low, possibly as a result of erosion of st ratigraphy on the higher, more exposed portions of the stratigraphic section. The side-scan data show little va riation of surficial sediments, apart from the striping due to furrows in the north, within this feature. Fu rrows are present in the northwestern portion of the low; however, they terminate abruptly at the edge of the low to the southwest. This suggests that the current regime responsible for the furrow formation may not ex tend down to the seafloor within this portion of the topographic low. Anti-dunes are present within the lo w; however, their effect on the seafloor is less pronounced than it is to the south.

A short portion of the Chinook Tie-Back routes will cross the furrowed topographic low (see Figure 22). Engineering of the routes appear feasible in this area with respect to the observed geologic and geotechnical conditions. The seafloor currents shoul d be considered with respect to the routes.



# Geotechnical Data

The Chinook area consists of a drill center that will tie-back to the Cascade FPSO via flowlines and umbilicals. The tie-back line traverses through the fu rrowed region. Three box cores were recovered from this area (Appendix B). The soil properties in the furrowed region are similar to those found in the furrowed region of the Cascade area (Section 3, Figure 13).

Two short cores, one jumbo piston core, and one box core were recovered from the future Chinook drill center location (Appendix B). All the geotechnical lab da ta is not available at this time. Based on the limited box core data, the moisture contents near surface seem to follow similar profile with depth as observed in the Cascade area, i.e., closer to 150% at surface and reducing to 65%-100% at 12-ft depth. The liquidity index also follows similar trends indicating ga in in strength with depth. The Chinook site consists of normally consolidated clays similar to those obser ved in the Cascade “Fluked” region (Section 3, page 22). 

# PROPRIETARY

# Project No. 1106-1257b SECTION 4

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# The soil sensitivity along the tie-back route based on the limited data appears to be low. However, the sensitivity of soils at the drill site based on one data poi nt appears to be low to medium. The strengths with depth based on all the data to date in this region are provided in the Figure 27 below.

Piston Core Box Core

CHPC-1 CHBOX-1

CHPC-2 CHBOX-2

CHPC-3 CHBOX-3

CHPC-4 CHBOX-4

CHBOX-5

CHBOX-6

CHBOX-7

CHBOX-8

Table 10. List of cores for the Chinook area, UCR province.

0 12 2 4 6 8 10



### Sensitivity

0 500 100 200 300 400



### MV Shear Strength (psf)

0 2.5 0.5 1 1.5 2 

### Liquidity Index (LI)

0 200 40 80 120 160 

### Moisture Content (%)

20 0

18 16 14 12 10 8 6 4 2Penetration below Seafloor(ft)



# Figure 27. Geotechnical test results for the Chinook area, UCR province.



# The strength of surficial material in certain areas can be expected to be as high as 200 psf. This results from the amount of erosion and reworking of the soils taking place within this area. The fluked region of the topographic low in the Cascade area shows signifi cant erosion, down to the “Triplet” (as defined earlier) in many places exposing older sediments with higher strengths at the seafloor. Whereas, the topographic low in Chinook as mentioned earlier shows a slight thickening of surficial sediments resulting in slightly lower strengths in this area.



# Chemosynthetic Communities

Chemosynthetic Communities are not expected w ithin the Chinook Development area. There is no evidence of hydrocarbon seepage to the seafloor in th e geophysical data. The multibeam data reveal an eroded seafloor exhibiting furrows and anti-dunes. Th e side-scan data does not indicate areas of hard seabed or expulsion features. The subbottom profile r data show generally parallel and continuous stratigraphy. 

# PROPRIETARY

# Project No. 1106-1257b SECTION 5

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# SECTION 5: SEAFLOOR AND SHALLOW GEOLOGIC CONDITIONS

OF THE CHINOOK TIE-B ACK PIPELINE CORRIDOR

Petrobras America Inc. (PAI) is evaluating development of the Chinook area in Walker Ridge Area (WR) in the Gulf of Mexico. PAI has proposed placing a drill center in Block 425 and tie-back flowlines extending from the drill center to the Cascade FPSO (S ection 3). The area surveyed for the tie-back corridor includes WR Blocks 249, 293, 337, 381 and 425 (Map 1C).

The planned pipeline corridor genera lly trends south to north from the Chinook drill center located in

south-central WR 425 to the Cascade FPSO location in southeastern WR 249. Two pipelines are planned in the corridor. The proposed pipelines are planned as straight line runs departing the Chinook drill center on a north-northeast bearing and crossing WR blocks 381, 337, 293, and ending at the Cascade FPSO riser

base PLETS located in WR 249.



# Water Depths and Gradient

Water Depth in the route corridor ranges from a bout -8,170 ft near the Cascade FPSO location in WR 249 to about -8,820 ft south of the Chinook drill cen ter in WR 425 (Maps 2C and 3C). Water depths increase relatively uniformly southward from the Cascade FPSO location to the Chinook drill center, shallowing slightly in northern WR 425.

Seabed gradients range from nearly flat to about 32° with an average along the west and east routes of 9° and 10°, respectively. The furrowed region of the corri dor contains irregular topography with the furrows exhibiting high slope angles along their walls. Seabed dip angle and orientati on will vary rapidly over short distances. The following table lists the range in water depth and average seabed gradient for the two

routes:

West Route
Minimum Water Depth -8,185 ft Sta. 690+66.71
Maximum Water Depth -8,794 ft Sta. 480+00 to 540+00 

# Average Seafloor Gradient 9o (15.7%) South



# East Route
Minimum Water Depth -8,190 ft Sta. 690+66.71
Maximum Water Depth -8,794 ft Sta. 480+00 to 540+00 

# Average Seafloor Gradient 10o (17.5%) South

Table 11. Water depth and gradient along the Tie-Back routes.



# Seafloor Currents

Seabed anti-dunes and furrows are present within th e pipeline corridor and cannot be avoided. The erosional nature of these features indicates the pr esence of potentially strong bottom currents (possibly exceeding 2 knots) within the tie-back corridor. These cu rrents may, at least in part, originate from strong eddies that spin off the Loop Current and “feel” bottom along the Escarpment.



# Seafloor Morphology and Soils

The route corridor has been divided into th ree soil provinces based on seafloor morphology and core data. The provinces are designated as Seafloor Anti-dunes, Seafloor Furrows, and Seafloor Flukes. Soils data from each province are provided by cores collected along the routes length.

Seafloor Anti-dunes. Anti-dunes are defined as low, undulating bedforms whose crests are in phase with the seafloor currents; therefore, they migrate by accre tion in the upstream direction. The anti-dunes in the within the corridor are typically 2 to 5 ft in height and spaced about 500 to 700 ft apart (Maps 2C and 3C). The side-scan sonar data in this portion of the corri dor show generally light reflectivity from the Chinook

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# drill center to the start of the furrow field (Map 2C a nd 3C). This correlates with the core data (i.e., CHBOX-5, CHPC-1, and CHPC-4) which collected primarily very soft clay from the seabed to 17 ft bml. Although, CHPC-1 did collect 0.42 inches of sand at the seabed demonstrating that some variability of soils can be expected.

Seafloor Furrows. Seafloor furrows are present along much of the route corridor and cannot be avoided.

The furrows are evident in the mu lti-beam data as linear features trending northeast to southwest. In general, individual furrows average about 100 ft wide and 30 ft deep and have relatively steeply dipping walls. The side-scan data show a striped seafloor of alternating light and dark areas (Maps 2C and 3C). Soils will vary from normally consolidated clays in th e areas between the furrows to stiffer, slightly overconsolidated clays, sand, and shell fragments along the furrow floors. The seafloor currents and resulting furrows should be considered with respect to pipeline engineering.



# Sediments

The surficial sediments along the proposed route w ill vary from silty and clayey sand to very soft clays, occasionally with shell fragments. Primarily soft clays are expected from the start of the routes to the furrows in the Chinook area. Silty sands, clayey sands, sandy clays, and clays mixed with shell fragments are expected along the route where furrows ar e present. North of the furrowed area to the end of the route in WR 293, the surficial sediments are compo sed of very soft clays over sandy clay grading to very soft clay westward.

Two short cores, one jumbo piston core, and one box core were recovered from the future Chinook drill center location (Appendix B). All the geotechnical lab da ta is not available at this time. Based on the limited box core data, the moisture contents near surface seem to follow similar profile with depth as observed in the Cascade area, i.e. closer to 150% at surface and reducing to 65%-100% at 12 ft depth. The liquidity index also follows similar trends indicating gain in strength with depth (Section 4, Figure 27). The strength of surficial material in certain areas can be expected to be as high as 200 psf. This results from the amount of erosion and reworking of the soils taking place within this area.

The near surface soils within this area are mainly very soft to soft high plastic clays becoming firm to stiff with depth (Appendix B). The strengths near surface are in the range of 15-50 PSF with maximum at some locations reaching up to 100 psf, a few inches below th e surface (Section 3, Figure 16). Interestingly, the CBOX-2 indicates strengths greater than 150 psf. It is believed that this sample is possibly sandy. A thin drape of foraminiferal clayey-sand is commonly observe d in furrowed areas. Ripple marks, indicative of a sandy seabed, have been observed in other furrowed re gions below the Escarpment. The moisture content varies between 150% near surface decreasing to 100% around 5-ft depth. The liquidity index near surface is in excess of two and drops to one at depth. Th e sensitivity data indicates low sensitivity over the entire

site

. The soils appear favorable for inst allation and operation of the flowlines.



# Man-made Features and Conditions

There are no man-made features or conditions that are considered to be a constraint to pipeline installation and operation. The proposed routes will not cross any shipping safety fairways, ordnance or waste disposal sites, or military areas. No shipwreck s are reported within the survey corridor or along the proposed route. No other man-made features or conditions occur along the proposed route that would hinder or constrain pipe-lay activities or operation.



# GEOLOGIC CONDITIONS ALONG THE PROPOSED WEST FLOWLINE ROUTE

The proposed West Gas Flowline begins at a PLET (p ipeline end termination) structure north of the Chinook drill center (start-of-line, Sta.00+00) and conti nues in a straight line segment to a PLET near the south riser base at the Cascade FPSO location (end-of- line, Sta. 611+81.01), Map 2C. From Sta. 00+00 to

Sta. 37+45 the route traverses seafloor anti-dunes in th e Chinook development area. Seafloor furrows are

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# present from Sta. 37+45.96 to Sta. 538+29.16. North of Sta. 538+29.16 to the end of the route the seafloor

contains flukes.

The following tables outline the coordinates for the be ginning, termination point, and block crossings as well as water depth and seafloor gradient along the West Flowline route.

Proposed 9 5/8-Inch Gas Pipeline West Route Description
Designation

Points X Coordinate (ft) Y Coordinate (ft) Latitude (degrees North) Longitude (degrees West) Station

Number
Start of Pipeline 2,446,912.87’ 9,633,069.91’ 26° 31’ 34.55” 90° 31’ 59.20” 00+00.00 

# Block Crossing

WR 425/381 2,448,319.95’ 9,646,560.00’ 26° 33’ 47.81” 90° 31’ 40.86” 135+63.28



# Block Crossing

WR 381/337 2,449,972.15’ 9,662,400.00’ 26° 36’ 24.29” 90° 31’ 19.29” 294+89.21



# Block Crossing

WR 337/293 2,451,624.34’ 9,678,240.00’ 26° 39’ 00.77” 90° 30’ 57.71” 454+15.14



# End of Pipeline 2,453,259.93’ 9,693,920.80’ 26° 41’ 35.67” 90° 30’ 36.32” 611+81.01

Table 12. West Tie-Back block crossings.



# Minimum Water Depth Maximum Water Depth Average Water Depth Maximum

Seafloor

Gradient Average Seafloor

Gradient

-8,185 ft -8,794 ft 32.7o / 57.1%

STA. 690+66.71 Sta. 480+00 to

540+00 -8,530 ft
STA. 184+35 9o / 15.7%

Table 13. Water depth and gradient along the west Tie-Back route.



# Man-made Features and Conditions

The proposed West Flowline will not cross any ex isting pipelines or wellsites. The locations of side-scan sonar targets relative to the proposed route are show on Maps 1C. The sonar targets are small

contacts with little or no relief and are believed to be unknown man-made debris. The nearest sonar targetis Target No. 24, located 316 ft east of the flowline route at Sta. 385+36.86 (Map 2C, Sheet 2). The preinstallation ROV survey should be able to identify th is potential debris and ascertain whether removal is required.



# Chemosynthetic Communities

Chemosynthetic communities are not expected along the West Flowline route. There is no evidence of hydrocarbon seepage to th e seafloor in the geophysical data. The occurrence of periodic strong

bottom currents in this area have scoured and eroded the seafloor. The multibeam data reveal an eroded seafloor exhibiting furrows, anti-dunes, and flukes. The side-scan data does not indicate areas of hard seabed or expulsion features.



# GEOLOGIC CONDITIONS ALONG THE PROPOSED EAST FLOWLINE ROUTE

The proposed East Gas Flowline begins at a PLET (p ipeline end termination) structure north of the Chinook drill center (start-of-line, Sta.00+00) and conti nues in a straight line segment to a PLET near the south riser base at the Cascade FPSO location (end-of-line, Sta. 610+61.81). From Sta. 00+00 to Sta.

38+88.70 the route traverses seafloor anti-dunes in the Chinook development area. Seafloor furrows are present from Sta. 38+88.70 to Sta. to Sta. 544+88.34. North of Sta. 544+88.34 to the end of the route the

seafloor contains flukes.

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# The following tables outlines the coordinates for the be ginning, termination point, and block crossings as well as water depth and seafloor gradient along the East Flowline route.

Proposed 9 5/8-Inch Gas Pipeline East Route Description
Designation

Points X Coordinate (ft) Y Coordinate (ft) Latitude (degrees North) Longitude (degrees West) Station

Number
Start of Flowline 2,447,145.93’ 9,633,044. 60’ 26° 31’ 34.25” 90° 31’ 56.64” 00+00.00 

# Block Crossing

WR 425/381 2,448,586.97’ 9,646,560.00’ 26° 33’ 47.76” 90° 31’ 37.92” 135+92.01



# Block Crossing

WR 381/337 2,450,275.86’ 9,662,400.00’ 26° 36’ 24.23” 90° 31’ 15.95” 295+21.79



# Block Crossing

WR 337/293 2,451,964.76’ 9,678,240.00’ 26° 39’ 00.70” 90° 30’ 53.96” 454+51.57



# End of Pipeline 2,453,619.77’ 9,693,762. 26’ 26° 41’ 34.03” 90° 30’ 32.39” 610+61.81

Table 14. West Tie-Back block crossings.



# Minimum Water Depth Maximum Water Depth Average Water Depth Maximum

Seafloor

Gradient Average Slope

-8,190 ft -8,794 ft 32.0o / 55.9%

STA. 690+66.71 Sta. 480+00 to

540+00 -8,531 ft
STA. 510+00 9o / 15.7%

Table 15. Water depth and gradient along the east Tie-Back route.



# Man-made Features and Conditions

The proposed East Flowline will not cross any ex isting pipelines or wellsites. The locations of side-scan sonar targets relative to the proposed route are show on Maps 1C. The sonar targets are small contacts with little or no relief. The nearest sonar target is Target No. 24, located 6.8 ft west of the flowline route at Sta. 385+37.94 (Map 3C, Sheet 2). The pre-inst allation ROV survey should be able to identify this potential debris and ascertain wh ether removal is required.



# Chemosynthetic Communities

Chemosynthetic communities are not expected along the East Flowline route. There is no evidence of hydrocarbon seepage to the seafloor in the geophysi cal data. The occurrence of periodic strong bottom

currents in this area have scoured and eroded the seaf loor. The multibeam data reveal an eroded seafloor exhibiting furrows, anti-dunes, and flukes. The side- scan data does not indicate areas of hard seabed or expulsion features.

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# SECTION 6: FINDINGS AND RECOMMENDATIONS

The Cascade and Chinook development has a planned FPSO facility to be emplaced in the southeast corner of WR 249, drill centers in WR 205, 249, and 425, a tie-back pipeline between the drill center in WR 425 and the FPSO, and various infield flowlines and umb ilicals. The proposed Cascade, Chinook, and Chinook Tie-Back flowlines appear feasible for development.

GEMS conducted an integrated geologic and geotechni cal study for the Cascade and Chinook Prospects. GEMS coordinated a geophysical survey conducted by C&C Technologies, Inc., using their AUV system to acquire multibeam swath bathymetry, sidescan s onar, and subbottom profiler data. An extensive geotechnical program has also been conducted. All data were used to assess the site conditions for the planned drilling and production activities.



# Cascade Development Area

The Cascade area displays a variety of seafloor and geologic features resulting from past salt-related structural deformation as well as past and present seafl oor erosion. The most prominent feature is the Sigsbee Escarpment, which crosses the northwestern part of the area. The Escarpment itself has variable gradients and thickness of sedimentary cover overlying ol der, very stiff to hard soils. Faulting in many places along the Escarpment results in a rough topogra phy, has uplifted and exposed older strata, and contributed to numerous past failures.

In the area of the development itself, below the Escarpment on the Upper Continental Rise, seafloor currents have significantly eroded the seabed below the Escarpment resulting in extensive furrows and flukes on the seafloor. The furrows average about 100 ft wide and 30 ft deep and have relatively steeply dipping walls and are tightly spaced, averaging between 75 and 100 ft apart. The flukes are about 150 to 200 ft in length and can be up to 10 ft in height, but more typically average between 5 and 8 ft high.

The following findings are made based on examina tion of available data for the Cascade area:

1. The water depth in the Cascade area varies from 5,637 ft to 8,510 ft and seafloor gradients range from nearly 0o to approximately 70° along the steeper portions of the Sigsbee Escarpment.

2. The area consists of three geomorphologic provin ces, the Lower Continental Slope, the Sigsbee Escarpment, and the Upper Continental Rise w ith the Escarpment crossing the northwestern portion of the area.

3. The Escarpment displays high slope angles and rugged topography.

4. Seafloor furrows and flukes are present over most of the proposed Cascade, Chinook, and Chinook Tie-Back proposed facilities areas.

5. Periodic strong seabed currents are responsible fo r the formation of the furrows and flukes.

6. Several gas expulsion mounds are observed on th e Lower Continental Slope in the northeast portion of WR 160, but these are over a mile from any possible future architecture (Export Option 2) and far from the main development below the Escarpment.

7. The shallow stratigraphy over the area consists ge nerally of parallel-bedde d, differentially eroded hemipelagic clays resulting in varying soil proper ties at the seabed. Sands and coarse lag deposits may exist in the bottom of the furrows and be distributed throughout the area.

8. Slump deposits from the Escarpment form debris apr ons that extend ~1.0 mile from the base of the Escarpment. The nearest proposed facility is 0.5 mile from the most distal apron.

9. There are no geologic constraints such as active fa ulting, gas venting, or hard bottom conditions that would impact field development. The pot ential for encountering chemosynthetic communities

is remote.

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# 10. .With the exception of the existing exploration wellsites, there are no other man-made structures reported in the Cascade area.



# Chinook Development Area

The Chinook Development appears feasible based on th e observed geologic and geotechnical data. The following findings are made based on examination of available data for the Chinook area:

1. Water depths in the Chinook Development area ra nge from 8,607 ft 9,260 ft and seafloor gradients range from nearly 0o to about 50° along the walls of furrows.

2. The shallow stratigraphy over the area consists ge nerally of parallel-bedde d, differentially eroded hemipelagic clays. Sands are present along the floors of the furrows.

3. The Chinook area displays active erosional seafloor features consisting of furrows and anti-dunes.

4. Periodic strong seabed currents are responsible fo r the formation of the furrows and anti-dunes.

5. The furrows are located in the northern portion of the area and the anti-dunes are present in the

south and west.

6. The furrows are similar in size and spaci ng as those identified in the Cascade area.

7. The anti-dunes are typically 2 to 5 ft in height and spaced about 500 to 700 ft apart.

8. The proposed Drill Center lies in the anti-dune area.

9. The proposed Chinook Tie-Back routes begin at the Drill Center in the anti-dune area and will encounter the furrows as they traver se north-northeast to the Cascade FPSO.

10. There are no geologic constraints such as active fa ulting, gas venting, or hard bottom conditions that would impact field development. The pot ential for encountering chemosynthetic communities

is remote.

11. With the exception of the existing exploration wellsites, there are no other man-made structures reported in the Cascade area.



# Chinook Tie-Back Corridor

The Tie-Back corridor traverses the seafloor between the Chinook Drill Center and the proposed Cascade

FPSO location. The seafloor within the corridor is furro wed over much of its length. Seafloor flukes exist at the northern end of the corridor, near the FPSO location, and anti-dunes are present at the Chinook Drill

Center in the south.

The following findings are made based on examination of available data for the Chinook area:

1. There are two proposed gas tie-back pipelines and one production umbilical in the corridor.

2. Water depths in the corridor range from -8,820 ft to -8,170 ft and seabed gradients in the corridor range from nearly 0o to locally approaching 32°, with an average along the west and east routes of 9° and 10°, respectively.

3. The shallow stratigraphy beneath the corridor consis ts generally of paralle l-bedded, differentially eroded hemipelagic clays. Sands are present along the floors of the furrows.

4. Periodic strong seabed currents are responsible fo r the formation of the furrows and anti-dunes.

5. Irregular seafloor consisting of anti-dunes, furrows, and flukes are present at various locations along the entire length of the corridor.

6. Sonar Contact No. 24 lies 6.8 feet from the proposed East Gas Pipeline Route at about Sta. 385+37.94. This target, which has no measurable height, is 4-ft wide, and 10-ft long, and may be modern debris. No other sonar contacts lie directly along the proposed pipeline or umbilical routes.

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# 7. There are no geologic constraints such as active faulti ng, gas venting, or hard bottom conditions that would impact pipeline lay operations. The potentia l for encountering chemosynthetic communities is

remote.



# Summary of Geologic and Geotechnical Findi ngs With Respect to Proposed Field

Architecture

The table beginning on the next page provides a summary of the geologic processes and geotechnical conditions for each of the physiographic provinces defi ned in sections 3, 4, and 5 of this report and describes which proposed facilities will fall into these conditions.Project No. 1106-1257bSECTION 6- 42 -Table 16. SUMMARY TABLE:PhysiographicRegionGeologic Conditions Geotechnical Properties Comments Planned Infrastructure

LOWER CONTINENTAL SLOPE1) The shallow stratigraphy, toapproximately 260 ft belowthe mud-line consists of welllayered to amorphousreflectors.2) The base of this surficial unitis identified as the “Triplet”.3) Carbon-14 dating of the threedistinct silt-rich layersindicate that the layers weredeposited between ~18.9 –20.2 ka (1ka=1000 yrs)slightly before the end of thelast low stand, i.e.,Pleistocene/Holoceneboundary.1) Soils in these areas aregenerally high plastic,clays with a lowsensitivity.2) The soils are fairlyuniform over the arealextent and are normallyto slightly overconsolidated.3) The moisture contentnear surface is in excessof 100% and it reducesto approximately 70% at20 ft depth.4) Shear strength increaseslinearly with depth. Thestrength of the surficialsediments variesbetween 40 psf and 70psf. At some locationsstrengths in surficialsediments have beenmeasured up to 150 psf.1) The Triplet is an importantmarker horizon in the areabecause it both marks the baseof the transitional latePleistocene (low-stand) andcurrent Holocene (high-stand)sediments. Both of these arepresent above and below theSigsbee Escarpment.2) Faults are present, caused bythe underlying salt movement,and have resulted in the upliftand erosion of the sedimentsabove the triplet in variousportions of the area. Belowthe Triplet the stratigraphy canbe characterized by parallelcontinuous layers.3) Occasionally, strengths insurficial sediments can beexpected to be as high as150 psf.The potential Gas Export Option 2route is the only plannedinfrastructure in this region. Thegeologic and geotechnicalconditions are favorable for pipelineinstallation and operation.

SIGSBEE ECARPMENT Upper Scarp1) The upper scarp is rugged,faulted, and steeply dipping.2) Faults are salt rooted, trendparallel to the Escarpmentface, and are typicallydownthrown to the southwest.Throw across the faults ishighly variable, but is asmuch as 20 ft.3) Thin to absent drape, oroutcropping stratacharacterize the upper andlower scarps.1) The moisture content ofnear surface sedimentsis in excess of 100% butdrops rapidly 50%within few inches.2) The shear strengths varybased on sampling ofthe normallyconsolidated drape orthe much stiffer,overconsolidatedunderlying strata.1) The currents are exposing thestiffer layers due to erosion.The potential Gas Export Option 2route will traverse the Upper Scarp.Spans and flowline stability shouldbe considered with respect toengineering. Future additional, sitespecific studies may be pertinentwith respect to topography, soils,stability, and chemosyntheticcommunities.Project No. 1106-1257bSECTION 6- 43 -PhysiographicRegionGeologic Conditions Geotechnical Properties Comments Planned Infrastructure

Bench1) The bench is widest andsmoothest in WR 205 andthins and becomes morerugged to the north and south.2) A possible drop in currentvelocity allows for thedeposition and ponding andpreservation of sediments, ofvarying thicknesses, over thebench.1) The strength of thesesediments is lower thanthe ones observed inboth the Upper andLower scarps. Thismaterial is underlain bystiffer material, probablythe continuation of thesequences observed inthe Upper and LowerScarps.2) The shear strengths varybased on sampling ofthe normallyconsolidated drape orthe much stiffer,overconsolidatedunderlying strata.1) The Bench is the transitionbetween the Upper Scarp andLower Scarp.The potential Gas Export Option 2route will traverse the Bench. Spansand flowline stability should beconsidered with respect toengineering. Future additional, sitespecific studies may be pertinentwith respect to topography, soils,stability, and chemosyntheticcommunities.

Lower Scarp1) Numerous slumps and gulliesincise the lower scarp withdebris aprons extending up toapproximately 1 mile out ontothe Upper Continental Rise.1) The liquidity index ofsurficial layer is slightlyless than 0.52) The shear strengths varybased on sampling ofthe normallyconsolidated drape orthe much stiffer,overconsolidatedunderlying strata. Thestrength of thisunderlying strata isobserved to be strongerthan that of the UpperScarp and Bench.1) Furrows are present on theEscarpment and indicateseabed currents are activelyeroding and re-depositing thesurficial sediments.2) Seafloor expression of athrust wedge is evident at thebase of the Lower Scarp.The potential Gas Export Option 2route will traverse the Lower Scarp.Spans and flowline stability shouldbe considered with respect toengineering. Future additional, sitespecific studies may be pertinentwith respect to topography, soils,stability, and chemosyntheticcommunities.Project No. 1106-1257bSECTION 6- 44 -PhysiographicRegionGeologic Conditions Geotechnical Properties Comments Planned Infrastructure

Furrows & Flukes1) This region is more extensivein the south, extending outfrom the Escarpment about3.5 miles, while to the norththe region thins, limited to theseafloor within about 2,000 ftof the Escarpment.2) A combination of thrust faultrelated uplift, slumpdeposition derived from theEscarpment and currenterosion result in a high degreeof variability in shallowseafloor soils.1) The near surfacemoisture content in thisregion is approximately100% reducing to 60%at depth.2) The soils are normallyto slightly overconsolidated.3) The liquidity index hasa value of 1.5 nearsurface and drops belowone at twelve feet depth.1) The area is between theEscarpment and “Fluke”region to the south. Thisforms the part of the “UpperContinental Rise”.2) The soils within this entireregion are generally uniformwith subtle differences intheir geotechnical properties.The SW Cascade drill center andinfield flowlines and umbilicalsassociated with the SW drill centerare located in this province.The geologic and geotechnicalconditions are favorable for shallowfoundations.The seafloor currents should beconsidered in this area.The topography of the furrows andflukes should be considered withrespect to placement of theindividual field architecture.

UPPER CONTINENTAL RISE Flukes1) Flukes are about 150 to 200 ftin length and can be up to 10ft in height, but moretypically average between 5and 8 ft high.2) Seafloor currents are thoughtto be stronger in flukedregions.1) High plastic normally toslightly overconsolidated clays atdepth.2) Moisture content inexcess 0f 100% nearsurface decreasing closeto 30% at 500 ft depth.3) Soils near surfaceslightly stiffer than“Furrowed” area.1) The side-scan sonar data showa mottled appearanceindicating a high variabilityin surficial sediments.2) Seafloor currents have erodedsurficial layer and exposedstiffer material near surfacein some areas. Strengthscloser to 400 psf can beexpected in those areas.3) Based on the current data, thestrength estimates determinedusing overall strengthrelationship with theexception of lower boundstrength, are expected to bewithin +25% of the locationspecific data.Infrastructure located within thisprovince include: the riser bases forthe FPSO, the north and southwestFPSO mooring clusters, infieldflowlines and umbilicals, and theChinook tie-back pipeline.The geologic and geotechnicalconditions are favorable for shallowfoundations.The seafloor currents should beconsidered in this area.The topography of the flukes shouldbe considered with respect toplacement of the individual fieldarchitecture..Project No. 1106-1257bSECTION 6- 45 -PhysiographicRegionGeologic Conditions Geotechnical Properties Comments Planned Infrastructure

Furrows1) In general individual furrowsaverage about 100 ft wide and30 ft deep and have relativelysteeply dipping walls.2) The furrows are tightlyspaced, averaging between 75and 100 ft apart.1) The soils are normallyto slightlyoverconsolidated2) The moisture content of150% near surfacedecreasing to 100%around 5ft depth.3) L.I. >2 near surface anddecreasing to one atdepth.4) The sensitivity dataindicates low sensitivity.1) Along the furrow floorsstrengths near surface can beexpected to be in excess of100 psf.2) Foraminifera sand may coverthe furrow floors as well asbe randomly distributed overthe area. This sand is mobile,being eroded and reworkedby periodic active seafloorcurrents.The FPSO southeast mooring clusteris located withinthis province.The geologic and geotechnicalconditions are favorable for shallowfoundations.The topography of the furrowsshould be considered with respect toplacement of the individualmoorings.The seafloor currents should beconsidered in this area.

Topographic Low1) The low is possibly theremnant of a filled channel orresults from landslidesemanating from theEscarpment to the south andeast of the Cascade area.2) The flukes and furrowscontinue into the low;however, their effect on theseafloor is less pronounced.1)The soils are normallyto slightlyoverconsolidated.1) Soils in this area are generallystronger than the soilsobserved in “Flukes” area.2) The strength estimatesdetermined using overallstrength relationship with theexception of lower boundstrength, are expected to be20-30% lower than thosedetermined using locationspecific data.The southwest FPSO mooringcluster and the Chinook tie-backpipeline are located within thetopographic low.The results of this study should beintegrated with the in-process deepgeotechnical investigation results toaddress foundation design for theFPSO moorings at Cascade.The topography of the furrows inthis area at Chinook should beconsidered in the pipeline design.The seafloor currents should beconsidered in this area.

UPPER CONTINENTAL RISE Seafloor Anti-Dunes1)The anti-dunes are typically 2to 5 ft in height and spacedabout 500 to 700 ft apart.2)The anti-dunes are randomlydistributed, but become lessprominent to the southwest.1) Normally consolidatedclays similar to the“fluked” province.2) The moisture content of150% near surfacedecreasing to 65%-100% at 12ft depth.3) The sensitivity dataindicates lowsensitivity.The Chinook drill center and the tieback pipeline are located in thisprovince.The geologic and geotechnicalconditions are favorable for shallowfoundations.The seafloor currents should beconsidered in this area.

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# Recommendations

The observations of the geologic and geotechnical conditions in the Cascade, Chinook, and Chinook TieBack Corridor appear feasible for development. We provide the following recommendations based on the observed conditions and our previ ous experience on deepwater projects below the Sigsbee Escarpment:

1. Consider the local seabed topography in the fu rrows, flukes, and furrow/flukes soil provinces at Cascade with respect to the placement of individual pieces of seafloor and shallow-founded field architecture such as FPSO moorings, PLETS, PLEMS, manifolds, pumps, and riser bases.

2. Consider the topography in the furrows, flukes, and furrow/flukes soil provinces at Cascade with respect to the design of infield, tie-back, and gas export flowlines.

3. Consider the periodically strong currents that have caused the erosion over this broad region with respect to scour and overall facilities engineering.

4. Conduct current monitoring studies to fully establish the range of velocities of these currents near

the seabed.

5. If Export Option 2 is selected, consider more site-sp ecific, detailed studies with respect to the local topography, soil conditions, slope stability, and pot ential presence of chemosynthetic communities on the Sigsbee Escarpment crossing.

6. Conduct a future slope stability assessment for the Sigsbee Escarpment to assess the slope conditions with respect to the locati on of the proposed facilities at Cascade.

7. Consider the topography through the furrowed regi ons with respect to detailed design of the Chinook Tie-Back flowlines upon completion of the planned higher-resolution bathymetric survey along the Chinook Tie-Back corridor.

8. Integrate the results of the Jumbo Piston Core and Rotary Soil Borings and PCPT geotechnical investigations with the existing geophysical and sh allow geotechnical data to assist in engineering design of the various seabed and shallow foundations.

If the facilities layouts for the various developments ar e modified, this report can be used as a basis to assess the geologic and very shallow geotechnical site conditions with respect to the new layout(s).

# Petrobras America, Inc. Development Operations Coordination Document Cascade / Chinook Development Project



# APPENDIX 3

Air Emissions Worksheets

# This page left blank intentionally.DOCD AIR QUALITY SCREENING CHECKLISTOMB Control No. 1010-0049OMB Approval Expires: August 31, 2006COMPANYPetrobras America, Inc.AREAWalker RidgeBLOCK206*LEASEOCS-G 16965*PLATFORMFPSOWELLCascade Wells No. 6 and 7COMPANY CONTACTGregory D. RolandTELEPHONE NO.(713) 808-2495REMARKSLEASE TERM PIPELINE CONSTRUCTION INFORMATION:YEAR NUMBER OF TOTAL NUMBER OF CONSTRUCTION DAYSPIPELINES2012020130201402015020160* Workbook details construction and production for thefollowing areas :Walker Ridge Block 206, Lease OCS-G 16965Walker Ridge Block 249, Lease OCS-G 16969 -->Location of FPSO (used for distance in exemption calculation)Walker Ridge Block 425, Lease OCS-G 16987Form MMS-139 (August 2003)Page 1 of 8AIR EMISSION CUMPUTATION FACTORSFuel Usage Conversion FactorsNatural Gas Turbines Natural Gas Engines Diesel Recip. Engine REF. DATESCF/hp-hr 9.524 SCF/hp-hr 7.143 GAL/hp-hr 0.0483AP42 3.2-1 4/76 & 8/84DrillshipGAL/hp-hr 0.0061Actual fuel burn - Email - Petrobras -USA 2/24/11Workboat (12,400 Hp)GAL/hp-hr 0.0100Actual fuel burn - Email - Petrobras -USA 2/24/11CrewboatGAL/hp-hr 0.0125Actual fuel burn - Email - Petrobras -USA 2/24/11Sea-going TugGAL/hp-hr 0.0145Actual fuel burn - Email - Petrobras -USA 2/24/11Diesel Generator - Essential & EGGAL/hp-hr 0.0478Actual fuel burn - Email - Petrobras -USA 2/24/11Main Engine (Sulzer)GAL/hp-hr 0.0366Actual fuel burn - Email - Petrobras -USA 2/24/11Diesel fire water pump (Fischcon)GAL/hp-hr 0.0511Actual fuel burn - Email - Petrobras -USA 2/24/11Turbine Solar Titan 130SCF/hp-hr 9.339Actual fuel burn - Email - Petrobras -USA 2/24/11Equipment/Emission FactorsunitsPMSOxNOxVOCCOREF.DATENG Turbines gms/hp-hr 0.00247 1.3 0.01 0.83AP42 3.2-1& 3.1-1 10/96NG 2-cycle lean gms/hp-hr 0.00185 10.9 0.43 1.5AP42 3.2-1 10/96NG 4-cycle lean gms/hp-hr 0.00185 11.8 0.72 1.6AP42 3.2-1 10/96NG 4-cycle rich gms/hp-hr 0.00185 10 0.14 8.6AP42 3.2-1 10/96Diesel Recip. < 600 hp. gms/hp-hr 1 1.468 14 1.12 3.03AP42 3.3-1 10/96Diesel Recip. > 600 hp. gms/hp-hr 0.32 1.468 11 0.33 2.4AP42 3.4-1 10/96Diesel Recip. > 600 hp. gms/hp-hr 8.1MARPOL 73/78* 3/07Crude Fired Recip. < 600 hp. gms/hp-hr 1 9.909 14 1.12 3.03AP42 3.3-1 10/96Crude Fired Recip. > 600 hp. gms/hp-hr 0.32 9.909 11 0.33 2.4AP42 3.4-1 10/96Diesel Boiler lbs/bbl 0.084 2.42 0.84 0.008 0.21AP42 1.3-12,14 9/98HFO Boiler lbs/bbl 0.42 16.335 2.31 0.012 0.21AP42 1.3-12,14 9/98NG Heaters/Boilers/Burners lbs/mmscf 7.6 0.593 100 5.5 84AP42 1.4-1, 14-2, & 14-3 7/98NG Flares lbs/mmscf 0.593 71.4 60.3 388.5AP42 11.5-1 9/91Liquid Flaring lbs/bbl 0.42 6.83 2 0.01 0.21AP42 1.3-1 & 1.3-3 9/98Tank Vapors lbs/bbl0.06AP42 5.2 7/08Fugitives lbs/hr/comp.0.0005API Study 12/93Glycol Dehydrator Vent lbs/mmscf6.6La. DEQ 1991Gas Venting lbs/scf0.0034Helicopter - Sikorsky H-60 Class lbs/hr 3.13 0.30 5.28 0.41 3.10AESO Memo 6/99Agusta Westland AW-139 lbs/hr 0.22 0.30 7.80 3.02 3.68FOCA 3/2009Sulfur Content Source Value UnitsFuel Gas 3.33 ppmDiesel Fuel 0.4 % weightHFO / Crude Oil 2.7 % weightProduced Gas( Flares) 3.33 ppmProduced Oil (Liquid Flaring) 1 % weight1.) "Deep Ocean Mendocino" MODU emissions based onmanufacturer's guarantee meeting regulation 13 ofANNEX VI of MARPOL 73/78 - 45 x (engine rpm)-0.2g/kWh.2.) "Dragon Quest" MODU emissions based on manufacturer's guarantee meeting regulation 13 of ANNEX VI of MARPOL 73/78 - 45 x (engine rpm)-0.2 g/kWh.4.) AW-139 Emissions: Swiss Confederation, Guidanceon the Determination of Helicopter Emissions, Federal Department of the Environment, Transport, Energy and Communications DETECFederal Office of Civil Aviation FOCA Division Aviation Policy and Strategy Edition 1 - March 2009. NoSO2emisisons are provide. Therefore, the emissions for a Sikorsky H-60 Class were used.3.) FPSO and Shuttle tank emissions are calculatedusing the vapor pressure curves(vapor pressure vs temperature) for each type of crude (AP42, Chptr 5).In cases where a vapor curve is notavailable for a given crude, the vapor curve for Arabian Light is used by Petrobras for internationaloperations (anything produced outside of Brazil).The US EPA, however, uses the vapor curvesassociated with Crude RVP5. Therefore, the emissions listed under Crude (RVP 5) should be considered as most representative of the FPSO operations.Form MMS-139 (August 2003)Page 2 of 8AIR EMISSIONS CALCULATIONS - 2012COMPANYAREABLOCK LEASE PLATFORM WELL CONTACT PHONE REMARKSPetrobras America, Inc. Walker Ridge206 OCS-G 16965 FPSO Cascade Wells No. 6 and 7 Gregory D. Roland (713) 808-2495 0OPERATIONSEQUIPMENTRATING MAX. FUEL ACT. FUEL RUN TIME MAXIMUM POUNDS PERHOURESTIMATED TONSDiesel EnginesHP GAL/HR GAL/DNat. Gas EnginesHP SCF/HR SCF/DBurnersMMBTU/HR SCF/HR SCF/D HR/D DAYS PM SOx NOx VOC CO PM SOx NOx VOCCOPRODUCTION FPSO - RECIP.> 600hp (1 Solar Titan 130 Total hp) standby 0 0 0 0 0 0 0 0 0 0 0 0 0 0FPSO - TURBINES Natural Gas (2 Solar Titan 130 Total hp - 57%) 22,167 207,020 4,968,487 24 365 0.12 63.47 0.49 40.53 0.53 278.02 2.14 177.50FPSO - RECIP.>600hp diesel Main (Sulzer) 100%11,828 433.2 10397.59 24 13.1 8.34 38.24 286.58 8.60 62.53 1.311 6.012 45.050 1.351 9.829FPSO - RECIP.>600hp diesel (2 Cummins QSK60-D(M) 1 100% /1 backup) Gen 2548 121.8 2922.65 24 12.5 1.80 8.24 61.731.85 13.47 0.269 1.236 9.260 0.278 2.020FPSO - RECIP.>600hp diesel (Cummins QSK60-D(M)) EG 1274 60.9 1461.33 1 26 0.90 4.12 30.87 0.93 6.73 0.012 0.054 0.4010.012 0.088FPSO - BURNER diesel (2 Dual Fuel Pyro Steam Boilers 1standby - 60%)) 21.524 365 0.38 14.62 2.07 0.01 0.19 1.65 64.03 9.05 0.05 0.82FPSO - RECIP.>600hp diesel (Fischcon Fire Pump - 50%) 701 35.8 859.31 1 26 1.54 2.27 21.61 1.73 4.68 0.02 0.03 0.28 0.020.06FPSO - IGG System burner (A & B)3224 52 0.57 22.05 3.12 0.02 0.28 0.35 13.76 1.95 0.010 0.18Shuttle Vessel - RECIP.>600hp diesel (Loading from FPSO) 3264 157.7 3783.6 24 52 2.30 10.55 79.08 2.37 17.25 1.44 6.59 49.35 1.48 10.77Shuttle Vessel - RECIP.>600hp diesel (Transit within 25miles) 11424 551.8 13242.7 24 20 8.05 36.94 276.79 8.30 60.391.93 8.87 66.43 1.99 14.49Shuttle Vessel - RECIP.>600hp diesel (Loading from FPSO) 3264 157.7 3783.6 24 52 2.30 10.55 79.08 2.37 17.25 1.44 6.59 49.35 1.48 10.77Shuttle Vessel - RECIP.>600hp diesel (Transit within 25miles) 11424 551.8 13242.7 24 20 8.05 36.94 276.79 8.30 60.391.93 8.87 66.43 1.99 14.49VESSELS >600hp Diesel (PSV Workboat 12400 hp, used at60%) 12400 124.2 2980 20 108 8.74 40.10 300.44 9.01 65.55 9.44 43.30 324.48 9.73 70.79VESSELS >600hp Diesel (PSV Workboat 12400 hp, used at60%) 12400 124.2 2980 20 108 8.74 40.10 300.44 9.01 65.55 9.44 43.30 324.48 9.73 70.79VESSELS >600hp Diesel (PSV Workboat 12400 hp, used at60%) 12400 124.2 2980 20 108 8.74 40.10 300.44 9.01 65.55 9.44 43.30 324.48 9.73 70.79VESSELS >600hp diesel (FSV Crew Boat)4120 51.67 1240 11 156 2.90 13.32 99.82 2.99 21.78 2 11 86 3 19VESSELS >600hp diesel (FSV Crew Boat)4120 51.67 1240 11 156 2.90 13.32 99.82 2.99 21.78 2 11 86 3 19VESSELS >600hp diesel (Sea-going Tug)5784 84.00 2016 24 365 4.08 18.70 140.14 4.20 30.58 18 82 614 18134DRILLING PRIME MOVER>600hp diesel (Drill Rig - 20%) Deep Ocean Mendocino 12840 394.0 9456 24 365 9.05 41.52 229.089.33 67.88 39.64 181.85 1003.39 40.88 297.30PRIME MOVER>600hp diesel (Drill Rig - 20%) Dragon Quest 12840 394.0 9456 24 365 9.05 41.52 229.08 9.33 67.88 39.64 181.85 1003.39 40.88 297.30MISC.BPD SCF/HR COUNTFPSO - TANK (Vapors @ Production Rate)72,000 24 365178.93197.10Shuttle tanker Loading - 50% IG330,000 24 52410.06128.70FLARE- (upset considered insignificant)0 0 0 0.00 0.00 0.00 0.00 0 0 0 0PROCESS VENT0 0 0 0.00 0.00FUGITIVES-11420.0 3655.7125.01GLYCOL STILL VENT-0.1471 24 3659.71E-074.25E-06AW-139 Helicopter (Production Operations)3060 139 3336.0 3 365 0.22 0.60 15.61 6.04 7.36 0.12 0.33 8.55 3.31 4.03DRILLING OIL BURN00 0 0.00 0.00 0.00 0.00 0.00 0 0 0 0 0WELL TEST GAS FLARE0 0 0 0.00 0.00 0.00 0.00 0 0 0 02012 YEAR TOTAL88.65 433.91 2896.08 691.61 697.60 140.91 715.26 4349.43 499.44 1223.34EXEMPTIONCALCULATIONDISTANCE FROM LAND IN MILES5494.50 5494.50 5494.50 5494.50 102282.55165.0Notes:1.) The air emissions worksheet only captures Shuttle Vessel air emissions while the Shuttle Vessel is within 25 miles of the FPSO.2.) Offloading from FPSO (20%), transit within 25 miles of FPSO (80%).Based on 1 Shuttle Vessel offloading every week.AIR EMISSIONS CALCULATIONS - 2013COMPANYAREABLOCK LEASE PLATFORM WELL CONTACT PHONE REMARKSPetrobras America, Inc. Walker Ridge206 OCS-G 16965 FPSO Cascade Wells No. 6 and 7 Gregory D. Roland (713) 808-2495 0OPERATIONSEQUIPMENTRATING MAX. FUEL ACT. FUEL RUN TIME MAXIMUM POUNDS PERHOURESTIMATED TONSDiesel EnginesHP GAL/HR GAL/DNat. Gas EnginesHP SCF/HR SCF/DBurnersMMBTU/HR SCF/HR SCF/D HR/D DAYS PM SOx NOx VOC CO PM SOx NOx VOCCOPRODUCTION FPSO - RECIP.> 600hp (1 Solar Titan 130 Total hp) standby 0 0 0 0 0 0 0 0 0 0 0 0 0 0FPSO - TURBINES Natural Gas (2 Solar Titan 130 Total hp - 57%) 22,167 207,020 4,968,487 24 365 0.12 63.47 0.49 40.53 0.53 278.02 2.14 177.50FPSO - RECIP.>600hp diesel Main (Sulzer) 100%11,828 433.2 10397.59 24 13.1 8.34 38.24 286.58 8.60 62.53 1.311 6.012 45.050 1.351 9.829FPSO - RECIP.>600hp diesel (2 Cummins QSK60-D(M) 1 100% /1 backup) Gen 2548 121.8 2922.65 24 12.5 1.80 8.24 61.731.85 13.47 0.269 1.236 9.260 0.278 2.020FPSO - RECIP.>600hp diesel (Cummins QSK60-D(M)) EG 1274 60.9 1461.33 1 26 0.90 4.12 30.87 0.93 6.73 0.012 0.054 0.4010.012 0.088FPSO - BURNER diesel (2 Dual Fuel Pyro Steam Boilers 1standby - 60%)) 21.524 365 0.38 14.62 2.07 0.01 0.19 1.65 64.03 9.05 0.05 0.82FPSO - RECIP.>600hp diesel (Fischcon Fire Pump - 50%) 701 35.8 859.31 1 26 1.54 2.27 21.61 1.73 4.68 0.02 0.03 0.28 0.020.06FPSO - IGG System burner (A & B)3224 52 0.57 22.05 3.12 0.02 0.28 0.35 13.76 1.95 0.010 0.18Shuttle Vessel - RECIP.>600hp diesel (Loading from FPSO) 3264 157.7 3783.6 24 52 2.30 10.55 79.08 2.37 17.25 1.44 6.59 49.35 1.48 10.77Shuttle Vessel - RECIP.>600hp diesel (Transit within 25miles) 11424 551.8 13242.7 24 20 8.05 36.94 276.79 8.30 60.391.93 8.87 66.43 1.99 14.49Shuttle Vessel - RECIP.>600hp diesel (Loading from FPSO) 3264 157.7 3783.6 24 52 2.30 10.55 79.08 2.37 17.25 1.44 6.59 49.35 1.48 10.77Shuttle Vessel - RECIP.>600hp diesel (Transit within 25miles) 11424 551.8 13242.7 24 20 8.05 36.94 276.79 8.30 60.391.93 8.87 66.43 1.99 14.49VESSELS >600hp Diesel (PSV Workboat 12400 hp, used at60%) 12400 124.2 2980 20 108 8.74 40.10 300.44 9.01 65.55 9.44 43.30 324.48 9.73 70.79VESSELS >600hp Diesel (PSV Workboat 12400 hp, used at60%) 12400 124.2 2980 20 108 8.74 40.10 300.44 9.01 65.55 9.44 43.30 324.48 9.73 70.79VESSELS >600hp Diesel (PSV Workboat 12400 hp, used at60%) 12400 124.2 2980 20 108 8.74 40.10 300.44 9.01 65.55 9.44 43.30 324.48 9.73 70.79VESSELS >600hp diesel (FSV Crew Boat)4120 51.67 1240 11 156 2.90 13.32 99.82 2.99 21.78 2 11 86 3 19VESSELS >600hp diesel (FSV Crew Boat)4120 51.67 1240 11 156 2.90 13.32 99.82 2.99 21.78 2 11 86 3 19VESSELS >600hp diesel (Sea-going Tug)5784 84.00 2016 24 365 4.08 18.70 140.14 4.20 30.58 18 82 614 18134DRILLING PRIME MOVER>600hp diesel (Drill Rig - 20%) Deep Ocean Mendocino 12840 394.0 9456 24 365 9.05 41.52 229.089.33 67.88 39.64 181.85 1003.39 40.88 297.30PRIME MOVER>600hp diesel (Drill Rig - 20%) Dragon Quest 12840 394.0 9456 24 365 9.05 41.52 229.08 9.33 67.88 39.64 181.85 1003.39 40.88 297.30MISC.BPD SCF/HR COUNTFPSO - TANK (Vapors @ Production Rate)80,000 24 365198.82219.00Shuttle tanker Loading - 50% IG330,000 24 52410.06128.70FLARE- (upset considered insignificant)0 0 0 0.00 0.00 0.00 0.00 0 0 0 0PROCESS VENT0 0 0 0.00 0.00FUGITIVES-11420.0 3655.7125.01GLYCOL STILL VENT-0.1471 24 3659.71E-074.25E-06AW-139 Helicopter (Production Operations)3060 139 3336.0 3 365 0.22 0.60 15.61 6.04 7.36 0.12 0.33 8.55 3.31 4.03DRILLING OIL BURN00 0 0.00 0.00 0.00 0.00 0.00 0 0 0 0 0WELL TEST GAS FLARE0 0 0 0.00 0.00 0.00 0.00 0 0 0 02013 YEAR TOTAL88.65 433.91 2896.08 711.50 697.60 140.91 715.26 4349.43 521.34 1223.34EXEMPTIONCALCULATIONDISTANCE FROM LAND IN MILES5494.50 5494.50 5494.50 5494.50 102282.55165.0Notes:1.) The air emissions worksheet only captures Shuttle Vessel air emissions while the Shuttle Vessel is within 25 miles of the FPSO.2.) Offloading from FPSO (20%), transit within 25 miles of FPSO (80%).Based on 1 Shuttle Vessel offloading every week.AIR EMISSIONS CALCULATIONS - 2014COMPANYAREABLOCK LEASE PLATFORM WELL CONTACT PHONE REMARKSPetrobras America, Inc. Walker Ridge206 OCS-G 16965 FPSO Cascade Wells No. 6 and 7 Gregory D. Roland (713) 808-2495 0OPERATIONSEQUIPMENTRATING MAX. FUEL ACT. FUEL RUN TIME MAXIMUM POUNDS PERHOURESTIMATED TONSDiesel EnginesHP GAL/HR GAL/DNat. Gas EnginesHP SCF/HR SCF/DBurnersMMBTU/HR SCF/HR SCF/D HR/D DAYS PM SOx NOx VOC CO PM SOx NOx VOCCOPRODUCTION FPSO - RECIP.> 600hp (1 Solar Titan 130 Total hp) standby 0 0 0 0 0 0 0 0 0 0 0 0 0 0FPSO - TURBINES Natural Gas (2 Solar Titan 130 Total hp - 57%) 22,167 207,020 4,968,487 24 365 0.12 63.47 0.49 40.53 0.53 278.02 2.14 177.50FPSO - RECIP.>600hp diesel Main (Sulzer) 100%11,828 433.2 10397.59 24 13.1 8.34 38.24 286.58 8.60 62.53 1.311 6.012 45.050 1.351 9.829FPSO - RECIP.>600hp diesel (2 Cummins QSK60-D(M) 1 100% /1 backup) Gen 2548 121.8 2922.65 24 12.5 1.80 8.24 61.731.85 13.47 0.269 1.236 9.260 0.278 2.020FPSO - RECIP.>600hp diesel (Cummins QSK60-D(M)) EG 1274 60.9 1461.33 1 26 0.90 4.12 30.87 0.93 6.73 0.012 0.054 0.4010.012 0.088FPSO - BURNER diesel (2 Dual Fuel Pyro Steam Boilers 1standby - 60%)) 21.524 365 0.38 14.62 2.07 0.01 0.19 1.65 64.03 9.05 0.05 0.82FPSO - RECIP.>600hp diesel (Fischcon Fire Pump - 50%) 701 35.8 859.31 1 26 1.54 2.27 21.61 1.73 4.68 0.02 0.03 0.28 0.020.06FPSO - IGG System burner (A & B)3224 52 0.57 22.05 3.12 0.02 0.28 0.35 13.76 1.95 0.010 0.18Shuttle Vessel - RECIP.>600hp diesel (Loading from FPSO) 3264 157.7 3783.6 24 52 2.30 10.55 79.08 2.37 17.25 1.44 6.59 49.35 1.48 10.77Shuttle Vessel - RECIP.>600hp diesel (Transit within 25miles) 11424 551.8 13242.7 24 20 8.05 36.94 276.79 8.30 60.391.93 8.87 66.43 1.99 14.49Shuttle Vessel - RECIP.>600hp diesel (Loading from FPSO) 3264 157.7 3783.6 24 52 2.30 10.55 79.08 2.37 17.25 1.44 6.59 49.35 1.48 10.77Shuttle Vessel - RECIP.>600hp diesel (Transit within 25miles) 11424 551.8 13242.7 24 20 8.05 36.94 276.79 8.30 60.391.93 8.87 66.43 1.99 14.49VESSELS >600hp Diesel (PSV Workboat 12400 hp, used at60%) 12400 124.2 2980 20 108 8.74 40.10 300.44 9.01 65.55 9.44 43.30 324.48 9.73 70.79VESSELS >600hp Diesel (PSV Workboat 12400 hp, used at60%) 12400 124.2 2980 20 108 8.74 40.10 300.44 9.01 65.55 9.44 43.30 324.48 9.73 70.79VESSELS >600hp Diesel (PSV Workboat 12400 hp, used at60%) 12400 124.2 2980 20 108 8.74 40.10 300.44 9.01 65.55 9.44 43.30 324.48 9.73 70.79VESSELS >600hp diesel (FSV Crew Boat)4120 51.67 1240 11 156 2.90 13.32 99.82 2.99 21.78 2 11 86 3 19VESSELS >600hp diesel (FSV Crew Boat)4120 51.67 1240 11 156 2.90 13.32 99.82 2.99 21.78 2 11 86 3 19DRILLING PRIME MOVER>600hp diesel (Drill Rig - 20%) Deep Ocean Mendocino 12840 394.0 9456 24 365 9.05 41.52 229.089.33 67.88 39.64 181.85 1003.39 40.88 297.30PRIME MOVER>600hp diesel (Drill Rig - 20%) Dragon Quest 12840 394.0 9456 24 365 9.05 41.52 229.08 9.33 67.88 39.64 181.85 1003.39 40.88 297.30VESSELS >600hp diesel (Sea-going Tug)5784 84.00 2016 24 365 4.08 18.70 140.14 4.20 30.58 18 82 614 18134MISC.BPD SCF/HR COUNTFPSO - TANK (Vapors @ Production Rate)80,000 24 365198.82219.00Shuttle tanker Loading - 50% IG330,000 24 52410.06128.70FLARE- (upset considered insignificant)0 0 0 0.00 0.00 0.00 0.00 0 0 0 0PROCESS VENT0 0 0 0.00 0.00FUGITIVES-11420.0 3655.7125.01GLYCOL STILL VENT-0.1471 24 3659.71E-074.25E-06AW-139 Helicopter (Production Operations)3060 139 3336.0 3 365 0.22 0.60 15.61 6.04 7.36 0.12 0.33 8.55 3.31 4.03DRILLING OIL BURN00 0 0.00 0.00 0.00 0.00 0.00 0 0 0 0 0WELL TEST GAS FLARE0 0 0 0.00 0.00 0.00 0.00 0 0 0 02014 YEAR TOTAL88.65 433.91 2896.08 711.50 697.60 140.91 715.26 4349.43 521.34 1223.34EXEMPTIONCALCULATIONDISTANCE FROM LAND IN MILES5494.50 5494.50 5494.50 5494.50 102282.55165.0Notes:1.) The air emissions worksheet only captures Shuttle Vessel air emissions while the Shuttle Vessel is within 25 miles of the FPSO.2.) Offloading from FPSO (20%), transit within 25 miles of FPSO (70%).Based on 1 Shuttle Vessel offloading every week.AIR EMISSIONS CALCULATIONS - 2015COMPANYAREABLOCK LEASE PLATFORM WELL CONTACT PHONE REMARKSPetrobras America, Inc. Walker Ridge206 OCS-G 16965 FPSO Cascade Wells No. 6 and 7 Gregory D. Roland (713) 808-2495 0OPERATIONSEQUIPMENTRATING MAX. FUEL ACT. FUEL RUN TIME MAXIMUM POUNDS PERHOURESTIMATED TONSDiesel EnginesHP GAL/HR GAL/DNat. Gas EnginesHP SCF/HR SCF/DBurnersMMBTU/HR SCF/HR SCF/D HR/D DAYS PM SOx NOx VOC CO PM SOx NOx VOCCOPRODUCTION FPSO - RECIP.> 600hp (1 Solar Titan 130 Total hp) standby 0 0 0 0 0 0 0 0 0 0 0 0 0 0FPSO - TURBINES Natural Gas (2 Solar Titan 130 Total hp - 57%) 22,167 207,020 4,968,487 24 365 0.12 63.47 0.49 40.53 0.53 278.02 2.14 177.50FPSO - RECIP.>600hp diesel Main (Sulzer) 100%11,828 433.2 10397.59 24 13.1 8.34 38.24 286.58 8.60 62.53 1.311 6.012 45.050 1.351 9.829FPSO - RECIP.>600hp diesel (2 Cummins QSK60-D(M) 1 100% /1 backup) Gen 2548 121.8 2922.65 24 12.5 1.80 8.24 61.731.85 13.47 0.269 1.236 9.260 0.278 2.020FPSO - RECIP.>600hp diesel (Cummins QSK60-D(M)) EG 1274 60.9 1461.33 1 26 0.90 4.12 30.87 0.93 6.73 0.012 0.054 0.4010.012 0.088FPSO - BURNER diesel (2 Dual Fuel Pyro Steam Boilers 1standby - 60%)) 21.524 365 0.38 14.62 2.07 0.01 0.19 1.65 64.03 9.05 0.05 0.82FPSO - RECIP.>600hp diesel (Fischcon Fire Pump - 50%) 701 35.8 859.31 1 26 1.54 2.27 21.61 1.73 4.68 0.02 0.03 0.28 0.020.06FPSO - IGG System burner (A & B)3224 52 0.57 22.05 3.12 0.02 0.28 0.35 13.76 1.95 0.010 0.18Shuttle Vessel - RECIP.>600hp diesel (Loading from FPSO) 3264 157.7 3783.6 24 52 2.30 10.55 79.08 2.37 17.25 1.44 6.59 49.35 1.48 10.77Shuttle Vessel - RECIP.>600hp diesel (Transit within 25miles) 11424 551.8 13242.7 24 20 8.05 36.94 276.79 8.30 60.391.93 8.87 66.43 1.99 14.49Shuttle Vessel - RECIP.>600hp diesel (Loading from FPSO) 3264 157.7 3783.6 24 52 2.30 10.55 79.08 2.37 17.25 1.44 6.59 49.35 1.48 10.77Shuttle Vessel - RECIP.>600hp diesel (Transit within 25miles) 11424 551.8 13242.7 24 20 8.05 36.94 276.79 8.30 60.391.93 8.87 66.43 1.99 14.49VESSELS >600hp Diesel (PSV Workboat 12400 hp, used at60%) 12400 124.2 2980 20 108 8.74 40.10 300.44 9.01 65.55 9.44 43.30 324.48 9.73 70.79VESSELS >600hp Diesel (PSV Workboat 12400 hp, used at60%) 12400 124.2 2980 20 108 8.74 40.10 300.44 9.01 65.55 9.44 43.30 324.48 9.73 70.79VESSELS >600hp Diesel (PSV Workboat 12400 hp, used at60%) 12400 124.2 2980 20 108 8.74 40.10 300.44 9.01 65.55 9.44 43.30 324.48 9.73 70.79VESSELS >600hp diesel (FSV Crew Boat)4120 51.67 1240 11 156 2.90 13.32 99.82 2.99 21.78 2 11 86 3 19VESSELS >600hp diesel (FSV Crew Boat)4120 51.67 1240 11 156 2.90 13.32 99.82 2.99 21.78 2 11 86 3 19VESSELS >600hp diesel (Sea-going Tug)578484.00 2016 24 365 4.08 18.70 140.14 4.20 30.58 18 82 614 18 134DRILLING PRIME MOVER>600hp diesel (Drill Rig - 20%) Deep Ocean Mendocino 12840 394.0 9456 24 365 9.05 41.52 229.089.33 67.88 39.64 181.85 1003.39 40.88 297.30PRIME MOVER>600hp diesel (Drill Rig - 20%) Dragon Quest 12840 394.0 9456 24 365 9.05 41.52 229.08 9.33 67.88 39.64 181.85 1003.39 40.88 297.30MISC.BPD SCF/HR COUNTFPSO - TANK (Vapors @ Production Rate)80,000 24 365198.82219.00Shuttle tanker Loading - 50% IG330,000 24 52410.06128.70FLARE- (upset considered insignificant)0 0 0 0.00 0.00 0.00 0.00 0 0 0 0PROCESS VENT0 0 0 0.00 0.00FUGITIVES-11420.0 3655.7125.01GLYCOL STILL VENT-0.1471 24 3659.71E-074.25E-06AW-139 Helicopter (Production Operations)3060 139 3336.0 3 365 0.22 0.60 15.61 6.04 7.36 0.12 0.33 8.55 3.31 4.03DRILLING OIL BURN00 0 0.00 0.00 0.00 0.00 0.00 0 0 0 0 0WELL TEST GAS FLARE0 0 0 0.00 0.00 0.00 0.00 0 0 0 02015 YEAR TOTAL88.65 433.91 2896.08 711.50 697.60 140.91 715.26 4349.43 521.34 1223.34EXEMPTIONCALCULATIONDISTANCE FROM LAND IN MILES5494.50 5494.50 5494.50 5494.50 102282.55165.0Notes:1.) The air emissions worksheet only captures Shuttle Vessel air emissions while the Shuttle Vessel is within 25 miles of the FPSO.2.) Offloading from FPSO (20%), transit within 25 miles of FPSO (70%).Based on 1 Shuttle Vessel offloading every week.AIR EMISSIONS CALCULATIONS - 2016COMPANYAREABLOCK LEASE PLATFORM WELL CONTACTPHONE REMARKSPetrobras America, Inc.Walker Ridge206 OCS-G 16965 FPSO Cascade Wells No. 6 and 7 GregoryD. Roland (713) 808-2495 0OPERATIONSEQUIPMENTRATING MAX. FUEL ACT. FUEL RUN TIME MAXIMUM POUNDS PERHOUR ESTIMATED TONS PER YEARDiesel EnginesHP GAL/HR GAL/DNat. Gas EnginesHP SCF/HR SCF/DBurnersMMBTU/HR SCF/HR SCF/D HR/D DAYS PM SOx NOx VOC CO PM SOx NOx VOCCOPRODUCTION FPSO - RECIP.> 600hp (1 Solar Titan 130 Total hp) standby 0 0 0 0 0 0 0 0 0 0 0 0 0FPSO - TURBINES Natural Gas (2 Solar Titan 130 Total hp - 57%) 22,167 207,017 4,968,405 24 365 0.12 63.47 0.49 40.53 0.53 278.01 2.14 177.50FPSO - RECIP.>600hp diesel Main (Sulzer) 100%11,828 433.2 10397.59 24 13.1 8.34 38.24 286.58 8.60 62.53 1.311 6.012 45.050 1.351 9.829FPSO - RECIP.>600hp diesel (2 Cummins QSK60-D(M) 1 100% /1 backup) Gen 2548 121.8 2922.65 24 12.5 1.80 8.24 61.73 1.85 13.47 0.269 1.236 9.260 0.278 2.020FPSO - RECIP.>600hp diesel (Cummins QSK60-D(M)) EG 1274 60.9 1461.33 1 26 0.90 4.12 30.87 0.93 6.73 0.012 0.054 0.4010.012 0.088FPSO - BURNER diesel (2 Dual Fuel Pyro Steam Boilers1 standby - 60%)) 21.524 365 0.38 14.62 2.07 0.01 0.19 1.65 64.03 9.05 0.05 0.82FPSO - RECIP.>600hp diesel (Fischcon Fire Pump - 50%) 701 35.8 859.31 1 26 0.49 2.27 16.98 0.51 3.70 0.01 0.03 0.22 0.010.05FPSO - IGG System burner (A & B)3224 52 0.57 22.05 3.12 0.02 0.28 0.35 13.76 1.95 0.010 0.18Shuttle Vessel - RECIP.>600hp diesel (Loading from FPSO)3264157.7 3783.6 24 52 2.30 10.55 79.08 2.37 17.25 1.44 6.59 49.351.48 10.77Shuttle Vessel - RECIP.>600hp diesel (Transit within 25miles)11424551.8 13242.7 24 20 8.05 36.94 276.79 8.30 60.39 1.93 8.87 66.43 1.99 14.49Shuttle Vessel - RECIP.>600hp diesel (Loading from FPSO)3264157.7 3783.6 24 52 2.30 10.55 79.08 2.37 17.25 1.44 6.59 49.351.48 10.77Shuttle Vessel - RECIP.>600hp diesel (Transit within 25miles)11424551.8 13242.7 24 20 8.05 36.94 276.79 8.30 60.39 1.93 8.87 66.43 1.99 14.49VESSELS >600hp Diesel (PSV Workboat 12400 hp, used at60%)12400 124.2 2980 20 108 8.74 40.10 300.44 9.01 65.55 9.44 43.30 324.48 9.73 70.79VESSELS >600hp Diesel (PSV Workboat 12400 hp, used at60%)12400 124.2 2980 20 108 8.74 40.10 300.44 9.01 65.55 9.44 43.30 324.48 9.73 70.79VESSELS >600hp Diesel (PSV Workboat 12400 hp, used at60%)12400 124.2 2980 20 108 8.74 40.10 300.44 9.01 65.55 9.44 43.30 324.48 9.73 70.79VESSELS >600hp diesel (FSV Crew Boat)4120 51.67 1240 11 156 2.90 13.32 99.82 2.99 21.78 2 11 86 3 19VESSELS >600hp diesel (FSV Crew Boat)4120 51.67 1240 11 156 2.90 13.32 99.82 2.99 21.78 2 11 86 3 19VESSELS >600hp diesel (Sea-going Tug)578484.00 2016 24 365 4.08 18.70 140.14 4.20 30.58 18 82 614 18 134DRILLING PRIME MOVER>600hp diesel (Drill Rig - 20%) Deep Ocean Mendocino12840394.0 9456 24 365 9.05 41.52 229.08 9.33 67.88 39.64 181.85 1003.39 40.88 297.30PRIME MOVER>600hp diesel (Drill Rig - 20%) Dragon Quest12840394.0 9456 24 365 9.05 41.52 229.08 9.33 67.88 39.64 181.85 1003.39 40.88 297.30MISC.BPD SCF/HR COUNTFPSO - TANK (Vapors @ Production Rate)48,00024 365119.29131.40Shuttle tanker Loading - 50% IG330,000 24 52410.06128.70FLARE- (upset considered insignificant)0 0 0 0.00 0.00 0.00 0.00 0 0 0 0PROCESS VENT00 0 0.00 0.00FUGITIVES-11420.0 3655.7125.01GLYCOL STILL VENT-0.1471 24 3659.71E-074.25E-06AW-139 Helicopter (Production Operations)3060 139 3336.0 3 365 0.22 0.60 15.61 6.04 7.36 0.12 0.33 8.55 3.31 4.03DRILLING OIL BURN00 0 0.00 0.00 0.00 0.00 0.00 0 0 0 0 0WELL TEST GAS FLARE0 0 0 0.00 0.00 0.00 0.00 0 0 0 02016 YEAR TOTAL87.60 433.91 2891.45 630.75 696.63 140.89 715.26 4349.36 433.72 1223.32EXEMPTIONCALCULATIONDISTANCE FROM LAND IN MILES5494.50 5494.50 5494.50 5494.50 102282.55165.0Notes:1.) The air emissions worksheet only captures Shuttle Vessel air emissions while the Shuttle Vessel is within 25 miles of the FPSO.2.) Offloading from FPSO (20%), transit within 25 miles of FPSO (80%).Based on 1 Shuttle Vessel offloading every week.AIR EMISSION CALCULATIONSOMB Control No. 1010-0049OMB Approval Expires: August 31, 2006COMPANY AREA BLOCK LEASE PLATFORM WELLPetrobras America, Inc. Walker Ridge 206 OCS-G 16965 FPSO Cascade Wells No. 6 and 7Emitted SubstanceYearPM SOx NOx VOC CO2012 140.91 715.26 4349.43 499.44 1223.342013 140.91 715.26 4349.43 521.34 1223.342014 140.91 715.26 4349.43 521.34 1223.342015 140.91 715.26 4349.43 521.34 1223.342016 140.89 715.26 4349.36 433.72 1223.32Allowable5494.50 5494.50 5494.50 5494.50 102282.55* Workbook details construction and production for the following areas :Walker Ridge Block 206, Lease OCS-G 16965Walker Ridge Block 249, Lease OCS-G 16969 --> Location of FPSO (used for distance in exemption calculation)Walker Ridge Block 425, Lease OCS-G 16987

# Petrobras America, Inc. Development Operations Coordination Document Cascade / Chinook Development Project



# APPENDIX 4

O il Spill Response Equipment
Response Times

# This page left blank intentionally.WCD Scenario– BASED ON WELL BLOWOUT DURING DRILLING OPERATIONS(165 miles from shore)18,135 bbls of crude oilAPI Gravity 23°APPENDIX 4– Equipment Response Time to WR 206Dispersants/SurveillanceDispersant/SurveillanceDispersantCapacity (gal)StorageCapacityPersonsReq.From HrstoProcureHrs toLoadoutTravel to siteTotal HrsCGABasler 67T 2000 NA 2 Houma 1 1 1.0 3.0ASIDC 3 1200 NA 2 Houma 1 1 1.3 3.3DC 3 1200 NA 2 Houma 1 1 1.3 3.3Aero Commander NA NA 2 Houma 1 1 1.0 3.0Offshore ResponseOffshore Equipment NoStagingEDRCStorageCapacityVOOPersonsRequiredFromHrs toProcureHrs toLoadoutHrs to GOMTravel toSpill SiteHrs toDeployTotalHrsCGAHOSS Barge 43000 4000 3 Tugs 8 Harvey 7 0 5 19.6 1 32.6Recovered Oil Storage NoStagingEDRCStorageCapacityVOOPersonsRequiredFromHrs toProcureHrs toLoadoutHrs to GOMTravel toSpill SiteHrs toDeployTotalHrsEnterprise Marine Services LLC (available through contract with CGA)CTCo 2605 NA 20000 1 Tug 6 Amelia 4 12 4 26.43 1 47.43CTCo 5001 NA 47000 1 Tug 6 Amelia 4 12 4 26.43 1 47.43Staging Area: VeniceOffshore Equipment WithStagingEDRCStorageCapacityVOOPersonsReq.FromHrs toProcureHrs toLoadoutTravel toStagingTravel toSiteHrs toDeployTotalHrsCGAFRU (1) + 100 bbl Tank (2) 3770 200 1 Utility 6 Belle Chasse 1 2 2 13.3 1 19.3FRU (3) + 100 bbl Tank (5) 11310 500 1 Utility 6 Houma 1 2 3 13.3 1 20.3FRU (1) + 100 bbl Tank (2) 3770 200 1 Utility 6 Lake Charles 1 2 5.5 13.3 1 22.8FRU (2) + 100 bbl Tank (4) 7540 400 1 Utility 6 Venice 1 2 0 13.3 1 17.342” Auto Boom (5000’) NA NA 10 Crew 20 Belle Chasse 1 2 2 13.3 1 19.342” Auto Boom (5000’) NA NA 10 Crew 20 Galveston 1 2 8 13.3 1 25.342” Auto Boom (5000’) NA NA 10 Crew 20 Houma 1 2 3 13.3 1 20.342” Auto Boom (2500’) NA NA 6 Crew 12 Ingleside 1 2 11 13.3 1 28.342” Auto Boom (5000’) NA NA 10 Crew 20 Lake Charles 1 2 5.5 13.3 1 22.842” Auto Boom (2500’) NA NA 6 Crew 12 Pascagoula 1 2 4 13.3 1 21.31000’ Hydro-Fire Boom NA NA 8 Utility 40 Harvey 1 4 2 13.3 6 26.3Nearshore ResponseNearshore EquipmentNo StagingEDRCStorageCapacityVOOPersonsRequiredFromHrs toProcureHrs toLoadoutHrs to GOMTravel toSpill SiteHrs toDeployTotalHrsCGA46’ FRV 5000 65 NA 4 Venice 1 0 1 2.0 0 4.0Enterprise Marine Services LLC(available through CGA contract)CTCo 2606 NA 20000 1 Tug 6 Amelia 4 12 4 15 1 36Staging Area: VeniceNearshore and InlandSkimmers With StagingEDRCStorageCapacityVOOPersonsReq.FromHrs toProcureHrs toLoadoutTravel toStagingTravel toDeploymentHrs toDeployTotalHrsCGASWS Egmopol 3000 100 NA 3 Galveston 1 2 8 2 0 13SWS Egmopol 3000 100 NA 3 Houma 1 2 3 2 0 8SWS Marco 3588 34 NA 3 Houma 1 2 3 2 0 8SWS Marco 3588 20 NA 3 Lake Charles 1 2 5.5 2 0 10.5Rope Mop 77 2 0 3 Belle Chasse 1 2 2 2 0 7RO Storage Barge NA 249 Towed 0 Galveston 1 2 8 2 0 13RO Storage Barge NA 249 Towed 0 Houma 1 2 3 2 0 8RO Storage Barge NA 249 Towed 0 Lake Charles 1 2 5.5 2 0 10.5RO Storage Barge NA 249 Towed 0 Venice 1 2 0 2 0 5Shoreline Protection18” Shoreline ProtectionBoomVOOPersonsReq.Storage/WarehouseLocationHrs toProcureHrs toLoadoutTravel toStagingTravel toDeployment SiteHrs toDeployTotal HrsStaging Area: CameronUSES (available through Letter of Intent)6000’ 18” Boom 5 Crew 14 Meraux, LA .5 .5 4.75 2 2 9.755000’ 18” Boom 3 Crew 8 Mobile, AL .5 .5 6 2 2 111000’ 18” Boom 1 Crew 3 Geismar, LA .5 .5 3.5 2 1 7.54500’ 18” Boom 3 Crew 8 Houston, TX .5 .5 2.5 2 2 7.54000’ 18” Boom 2 Crew 6 Venice, LA .5 .5 6.25 2 2 11.252000’ 18” Boom 1 Crew 3 Jackson, MS .5 .5 5.75 2 1 9.752000’ 18” Boom 1 Crew 3 Southaven, MS .5 .5 8.75 2 1 12.751000’ 18” Boom 1 Crew 3 Nashville, TN .5 .5 12.25 2 1 16.251500’ 18” Boom 1 Crew 3 Birmingham, AL .5 .5 9.25 2 1 13.251000’ 18” Boom 1 Crew 3 Biloxi, MS .5 .5 5.5 2 1 9.5Staging Area: GalvestonMiller (available through Letter of Intent)14,000’ 18” Boom 6 Crew 12 Sulphur, LA .5 1 2.75 2 2 8.2514,000’ 18” Boom 6 Crew 12 Beaumont, TX .5 1 2 2 2 7.560,000’ 18” Boom 10 Crew 20 Corpus Christi, TX .5 2 4.25 2 8 16.75Staging Area: VeniceAMPOL (available through Letter of Intent)42,000’ 18” Boom 16 Crew 40 New Iberia, LA 2 2 4 2 12 2220,000’ 18” Boom 8 Crew 20 New Orleans, LA 2 2 2 2 6 14Oil Mop (available through Letter of Intent)10,000’ 18” Boom 4 Crew 10 New Iberia, LA 1 1 4 2 3 1110,000’ 18” Boom 4 Crew 10 Houston, TX 1 1 7.5 2 3 14.510,000’ 18” Boom 4 Crew 10 Port Arthur, TX 1 1 6.25 2 3 13.2520,000’ 18” Boom 8 Crew 20 Belle Chasse, LA 1 1 1.75 2 6 11.7510,000’ 18” Boom 4 Crew 10 Port Allen, LA 1 1 3.5 2 3 10.510,000’ 18” Boom 4 Crew 10 Houma, LA 1 1 3.5 2 3 10.515,000’ 18” Boom 6 Crew 14 Gretna, LA (Warehouse) 2 2 2 2 4 12Staging Area: VeniceBeach Boom EDRCStorageCapacityVOOPersonsReq.FromHrs toProcureHrs toLoadoutTravel toStagingTravel toDeploymentHrs toDeployTotalHrsCGABeach Boom (2000’) NA NA NA 6 Galveston 1 2 8 1 2 14Beach Boom (1000’) NA NA NA 4 Ingleside 1 2 11 1 2 17Beach Boom (2000’) NA NA NA 6 Pascagoula 1 2 4 1 2 10Wildlife Response EDRCStorageCapacityVOOPersonsReq.FromHrs toProcureHrs toLoadoutTravel toStagingTravel toDeploymentHrs toDeployTotalHrsCGAWildlife Support Trailer NA NA NA 2 Houma 1 2 3 1 2 9Bird Scare Guns (24) NA NA NA 2 Belle Chasse 1 2 2 1 2 8Bird Scare Guns (12) NA NA NA 2 Galveston 1 2 8 1 2 14Bird Scare Guns (24) NA NA NA 2 Houma 1 2 3 1 2 9Bird Scare Guns (12) NA NA NA 2 Ingleside 1 2 11 1 2 17Bird Scare Guns (24) NA NA NA 2 Lake Charles 1 2 5.5 1 2 11.5Bird Scare Guns (24) NA NA NA 2 Pascagoula 1 2 4 1 2 10Response Asset TotalOffshore EDRC 69,390Offshore Recovered Oil Storage 72,300Nearshore / Shallow Water EDRC 18,253Nearshore / Shallow Water Recovered Oil Storage 21,317

# Petrobras America, Inc. Development Operations Coordination Document Cascade / Chinook Development Project



# APPENDIX 5

Oil Spill Risk Analysis (OSRA) Report

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# Petrobras America, Inc. Development Operations Coordination Document Cascade / Chinook Development Project



# APPENDIX 6

Worst-Case Discharge Evaluation

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