technical appendix g: geographic exposure, accident and oil

August 31, 2008

TECHNICAL APPENDIX G:GEOGRAPHIC EXPOSURE, ACCIDENT AND

OIL OUTFLOW PROFILES

Assessment of Oil Spill Risk due to Potential IncreasedVessel Traffic at Cherry Point, Washington

Submitted by VTRA TEAM:Johan Rene van Dorp (GWU), John R. Harrald (GWU),

Jason R.. W. Merrick (VCU) and Martha Grabowski (RPI)

Vessel Traffic Risk Assessment (VTRA) - Final Report 08/31/08

Technical Appendix G: Geographic Exposure, Accident and Oil Outflow Profiles G-2

TABLE OF CONTENTS

G-1. Roadmap of Appendix G................................................................................................... G-5

G-2. System Context Presentation........................................................................................... G-8

G-3. Summary Aggregate Results Presentations.................................................................G-20

G-4. Callibration VTRA CASE B Presentations G-4.1. VTRA CASE B: Traffic Density....................................................................... G-45 G-4.2. VTRA CASE B: Aggregate Results.................................................................. G-47 G-4.3. VTRA CASE B: Collision.................................................................................. G-55 G-4.4. VTRA CASE B: Powered Grounding..............................................................G-63 G-4.5. VTRA CASE B: Drift Grounding.................................................................... G-69 G-4.6. VTRA CASE B: Allisions...................................................................................G-75 G-4.7. VTRA CASE B: Accident Probability Presentation.......................................G-81

G-5. VTRA Case Comparison: A-B-C Presentations G-5.1. A-B-C: Exposure Presentation.......................................................................... G-86 G-5.2. A-B-C: Accident Frequency Presentation........................................................G-90 G-5.3. A-B-C: Aggregate Oil Outflow Presentation...................................................G-94 G-5.4. A-B-C: BP Persistent Oil Outflow Presentation.............................................G-98 G-5.5. A-B-C: BP Non-Persistent Oil Outflow Presentation.................................G-102 G-5.6. A-B-C: Interacting Vessel Persistent Oil Outflow Presentation................ G-106 G-5.7. A-B-C: Interacting Vessel Non-Persistent Oil Outflow Presentation.......G-110

G-6. VTRA Case Comparison: B-D-E Presentations G-6.1. B-D-E: Exposure Presentation....................................................................... G-114 G-6.2. B-D-E: Accident Frequency Presentation..................................................... G-118 G-6.3. B-D-E: Aggregate Oil Outflow Presentation................................................G-122 G-6.4. B-D-E: BP Persistent Oil Outflow Presentation..........................................G-126 G-6.5. B-D-E: BP Non- Persistent Oil Outflow Presentation............................... G-130 G-6.6. B-D-E: Interacting Vessel Persistent Oil Outflow Presentation................G-134 G-6.7. B-D-E: Interacting Vessel Non-Persistent Oil Outflow Presentation...... G-138



TABLE OF CONTENTS (Continued)

G-7. VTRA Case Comparison: B-F-G Presentations G-7.1. B-F-G: Exposure Presentation........................................................................G-142 G-7.2. B-F-G: Accident Frequency Presentation......................................................G-146 G-7.3. B-F-G: Aggregate Oil Outflow Presentation................................................ G-150 G-7.4. B-F-G: BP Persistent Oil Outflow Presentation.......................................... G-154 G-7.5. B-F-G: BP Non- Persistent Oil Outflow Presentation................................G-160 G-7.6. B-F-G: Interacting Vessel Persistent Oil Outflow Presentation................ G-162 G-7.7. B-F-G: Interacting Vessel Non-Persistent Oil Outflow Presentation.......G-166

G-8. VTRA Case Comparison: B-H-I Presentations G-8.1. B-H-I: Exposure Presentation.........................................................................G-170 G-8.2. B-H-I: Accident Frequency Presentation.......................................................G-174 G-8.3. B-H-I: Aggregate Oil Outflow Presentation................................................. G-178 G-8.4. B-H-I: BP Persistent Oil Outflow Presentation G-182................................................ G-8.5. B-H-I: BP Non- Persistent Oil Outflow Presentation.................................G-186 G-8.6. B-H-I: Interacting Vessel Persistent Oil Outflow Presentation................. G-190 G-8.7. B-H-I: Interacting Vessel Non-Persistent Oil Outflow Presentation........G-194

G-9. VTRA Case Comparison: B-J-H-K Presentations G-9.1. B-J-H-K: Exposure Presentation.................................................................... G-198 G-9.2. B-J-H-K: Accident Frequency Presentation..................................................G-203 G-9.3. B-J-H-K: Aggregate Oil Outflow Presentation.............................................G-208 G-9.4. B-J-H-K: BP Persistent Oil Outflow Presentation.......................................G-213 G-9.5. B-J-H-K: BP Non- Persistent Oil Outflow Presentation............................G-217 G-9.6. B-J-H-K: Interacting Vessel Persistent Oil Outflow Presentation............ G-223 G-9.7. B-J-H-K: Interacting Vessel Non-Pers. Oil Outflow Presentation........... G-228



TABLE OF CONTENTS (Continued)

G-10. VTRA Case Comparison: B-L-H-M Presentations G-10.1. B-L-H-M: Exposure Presentation................................................................ G-233 G-10.2. B-L-H-M: Accident Frequency Presentation.............................................. G-237 G-10.3. B-L-H-M: Aggregate Oil Outflow Presentation G-.243............................................. G-10.4. B-L-H-M: BP Persistent Oil Outflow Presentation...................................G-248 G-10.5. B-L-H-M: BP Non- Persistent Oil Outflow Presentation........................ G-253 G-10.6. B-L-H-M: Interacting Vessel Persistent Oil Outflow Presentation.........G-258 G-10.7. B-L-H-M: Interacting Vessel Non-Pers. Oil Outflow Presentation........G-263

G-11. VTRA Case Comparison: B-N-H-O Presentations G-11.1. B-N-H-O: Exposure Presentation................................................................G-268 G-11.2. B-N-H-O: Accident Frequency Presentation..............................................G-273 G-11.3. B-N-H-O: Aggregate Oil Outflow Presentation........................................ G-278 G-11.4. B-N-H-O: BP Persistent Oil Outflow Presentation.................................. G-283 G-11.5. B-N-H-O: BP Non- Persistent Oil Outflow Presentation........................G-288 G-11.6. B-N-H-O: Interacting Vessel Persistent Oil Outflow Presentation........ G-293 G-11.7. B-N-H-O: Interacting Vessel Non-Pers. Oil Outflow Presentation....... G-298



G-1. Roadmap of Appendix GThis Appendix is a compilation of the various analysis results that were generated over thecourse of the VTRA project. The VTRA project studies in various levels of detail thedifference cases presented in Table 1 below. The calibration case for this project was the year2005 (VTRA Case B). For this year we are effectively replaying the movement of vesselsrather than having to make use of additional probabilistic traffic arrival generators. Hence,VTRA CASE B is a natural calibration scenario. Also please note that in VTRA CASE B thenorth wing of the Cherry Point dock is in operation. VTRA CASE C runs the same trafficbut without this north wing in operation. A more detailed description of the various cases isprovided in the main report. Within the main report we have distilled the various generaltrends within the analysis results across the different VTRA Cases. Appendix G and itspresentations allow a reader of the report to study the analysis results and comparisonsdiscussed in the main report in more detail.

Table G-1. The 15 VTRA Cases

Case CP Traffic Other Traffic North Wing? Saddlebags? Extend Escorting? Neah Bay? Gate Way?1 A 2000 2000 No Yes No Yes No2 B 2005 2005 Yes Yes No Yes No3 C 2005 2005 No Yes No Yes No4 D 2025 Low 2025 Low Yes Yes No Yes Yes5 E 2025 Low 2025 Low No Yes No Yes Yes6 F 2025 Medium 2025 Medium Yes Yes No Yes Yes7 G 2025 Medium 2025 Medium No Yes No Yes Yes8 H 2025 High 2025 High Yes Yes No Yes Yes9 I 2025 High 2025 High No Yes No Yes Yes

10 J 2005 2005 Yes No No Yes No11 K 2025 High 2025 High Yes No No Yes Yes12 L 2005 2005 Yes Yes Yes Yes No13 M 2025 High 2025 High Yes Yes Yes Yes Yes14 N 2005 2005 Yes Yes No No No15 O 2025 High 2025 High Yes Yes No No Yes

Our study was limited to those vessels that dock at the BP Cherry Point dock. These vesselsinvolve both tankers, articulated tug barges (ATB) and integrated tug barges (ITB) dockingat BP Cherry Point. This class of vessels are here an in the various appendices and mainreport referred to as the BPCHPT vessels.

The summary aggregate results presentation provides a quick overview of aggregate resultsacross all the cases in Table 1 in terms of interactions (i.e. exposure), accident frequency andoil outflow. If a one is intrigued by a particular comparison as a result of this aggregate resultpresentation, one can further study this comparison using one of the comparison



presentations. Each presentation is a power point file with in it various geographic profilesfrom an exposure, accident frequency and oil outflow perspective. Separate presentations areprovided that compare oil outflow by:

• Persistent oil outflow from BPCHPT vessels (specifically crude oil and heavy fuel),• Non-persistent oil outflow from BPCHPT vessels (specifically refined products and diesel fuel).• Persistent oil outflow from interacting vessels (specifically crude oil and heavy fuel) involved in a potential collision with a BPCHPT vessel,• Non-persistent oil outflow from interacting vessels (specifically refined products and diesel fuel) involved in a potential collision with a BPCHPT vessel.

For the VTRA CASE B we analyzed a total annual average oil outflow of about 141 cubicmeters. Of this total, 122.1 cubic meters was average persistent oil outflow from BPCHPTVessels and 15.3 cubic meters was non-persistent oil outflow from BPCHPT vessels.Summarizing, of the total annual average oil outflow analyzed only about 2.5% can beattributed to an oil outflow from interacting vessel involved in a potential collision with aBPCHPT vessel.

The first presentation in the table of contents of Appendix G provides a system context forthe traffic that we were tasked to investigate. From the systems context presentation oneobserves immediately the following very interesting results for the calibration VTRA CASEB:

• Of the total simulated traffic, the CHPT vessel traffic only constitutes 1.1%. • Of the total simulated traffic, all tankers, ATB's and ITB's only constitutes 3%. • Of the total simulated deep draft traffic, the CHPT vessel traffic only constitutes 7%. • Of the total simulated deep draft traffic, all tankers, ATB's and ITB's only constitutes 16%.

As a result a disclaimer is in order: One should tread extremely cautiously when derivingrecommendations from any study that only evaluated 1.1% of the total traffic. One primarylimitation of the VTRA study is that, due to scoping constraints, the results reflect only on asmall percentage of the vessel traffic described in the maritime simulation. If riskinterventions have an appreciable effect beyond the BPCHPT vessels analyzed in this study,they should also be tested against this larger class of vessels to determine their effects on



system wide accident frequencies and oil outflows. For example, a risk intervention thatreduces accident frequency and or oil outflow of BP Cherry Point vessels, but results in alarger potential increase of accident frequency and/or oil outflows from the other trafficshould not be implemented. Conversely, risk mitigation measures that have little or noimpact on the BP Cherry Point vessels accident frequency or oil outflow may in factsignificantly reduce risk to other vessels.

From our oil outflow analysis it followed that in VTRA CASE B 97.5% of the total annualaverage oil outflow originated from BP Cherry Point vessels and only 2.5% from interactingvessels involved in a potential collision with a BP Cherry Point vessels. This class ofinteracting vessels also included tank vessels that do not dock at Cherry Point. Hence, wemay cautiously infer that of the total average oil outflow that we analyzed for VTRA CASEB only a small percentage can be attributed to diesel fuel of heavy fuel losses and thedominant part results from cargo losses. With the observations above, one could argue thatany risk interventions to reduce oil outflow potential that are in place or being considered forimplementation (now or in the future) should first be tested at a minimum for annualaverage oil outflow reduction effectiveness from all tank vessels. It should be noted that thisstudy did not analyze the oil outflow of tank vessels of those accidents that do not involveBPCHPT vessels.

technical appendix g: geographic exposure, accident and oil

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