Montara Oil Spill

Inquiry Analysis –

Oil Spill Response

Report to WWF-Australia 

February 2010

Prepared By:

Contract Reference # 122305

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Montara Oil Spill Inquiry Analysis – Oil Spill Response 

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P.O. Box 175 

Seldovia, Alaska 99663 

tel 907.234.7821 

fax 509.278.4406 

contact@nukaresearch.com

Front cover photo credit: Skytruth.org 

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Executive Summary 

This report was developed by Nuka Research and Planning Group, LLC under contract 

#122305 to provide WWF-Australia with analysis relevant to the Terms of Reference 

developed by the Montara Commission of Inquiry (the Inquiry) into the Uncontrolled 

Release of hydrocarbons at the Montara Wellhead Platform that commenced on 21 August 

2009. 

The objective of this report is to provide WWF-Australia with analysis of those Terms of 

Reference (TOR) that relate specifically to the adequacy of spill response and 

environmental impacts during the Montara Wellhead Platform Uncontrolled Release. The 

Terms of Reference related to the Adequacy of Response and Environmental Impacts are 

TOR 5 (Adequacy of Blowout Response), TOR 6 (Adequacy of Regulatory Obligations), 

and TOR 7 (Environmental Impacts Monitoring Activities). 

Nuka Research and Planning Group, LLC has reviewed documentation available via the 

Montara Commission of Inquiry including all Submissions and supporting documentation, 

the Terms of Reference, and the Hearing Schedule and Policies established by the 

Commission of Inquiry. This report represents our observations and recommendations 

regarding the response to the Montara incident. 

There are a few areas relating to the Adequacy of Response to the Uncontrolled Release 

(TOR 5) that should be further explored through the Inquiry process. 

• Voluntary well ignition does not appear to have been considered as a well 

control measure, although this may have been a viable option, as it could 

have been implemented more quickly than relief well drilling. 

• The time required to mobilize and transport the relief well drilling rig (3 

weeks) could have been reduced if a rig had been locally available closer to 

the spill site. 

• The Commission should review the operators’ exploration plans and oil spill 

contingency plans to determine whether these plans made any specific 

commitments regarding blowout control resources or decision-making. If 

so, then this represents a need for stricter oversight. 

There are a few areas relating to the Adequacy of Regulatory Obligations (TOR 6) that 

should be further explored through the Inquiry process. 

• National well control standards and requirements for operators should be 

reviewed. Operators who have identified a relief well as a blowout control 

measure could be compelled through regulation or permit to have a rig on 

standby to drill relief wells, thus avoiding delays like the initial delay at 

Montara while the rig was mobilized from Indonesia to Singapore and 

finally to the spill site. 

• The response techniques used during the response were primarily 

dispersants, and very little oil was mechanically recovered with boom and 

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skimmers. While there does not appear to have been any violation of 

national policy, the heavy reliance on dispersants is not entirely consistent 

with the stated national policy that mechanical recovery is the preferred 

method of clean-up. The National Plan policies on response technique 

selection should be reviewed to provide additional clarity about the use of 

dispersants vs. mechanical recovery for offshore spills. 

• The National Plan policies on Dispersant Application should be reconsidered regarding the potential for combinations of various dispersant 

chemicals to pose additional environmental toxicity. The national 

dispersant policy should also include some testing for environmental 

toxicity, particularly in instances where such a large volume of dispersants 

is applied over such a long period of time. 

• Decisions about response technique selection were made without public 

input or review. The National Plan could be modified to include a better 

mechanism to allow either ad hoc or standing bodies of citizens and 

stakeholders to communicate their priorities and concerns to response 

decision-makers. 

• Future oil and gas exploration operations should include stricter parameters 

for environmental monitoring and sampling, including requirements for 

baseline studies, and operators should have a clear understanding of the 

types of environmental monitoring studies that should be initiated and 

conducted during and after a release. 

There are a few areas relating to the Adequacy of Environmental Monitoring (TOR 7) that 

should be further explored through the Inquiry process. 

• The Environmental Monitoring Plan that establishes both the Operational 

and Scientific Monitoring Studies was developed through negotiation 

between PTTEPA and DEWHA. It is unclear the level to which this process 

may have compromised the scientific diligence of the monitoring studies. 

Overall, the Operational monitoring conducted to date and the Scientific 

Monitoring proposed is weak and vague and is not consistent with the 

Precautionary Principle. 

• There appears to have been a significant lack of transparency in the design, 

implementation, and data reporting for many environmental monitoring 

activities. The DEWHA website contains only superficial information and 

initial reports from Operational Modeling. Methodologies for the Scientific 

Monitoring studies do not appear to be within the public domain. 

• The fact that environmental monitoring was delayed and in many cases, 

superficial, results in a loss of valuable information that is needed to fully 

understand the extent of the spill’s impacts. Absent this knowledge, it is 

nearly impossible to effectively remediate those impacts and restore 

injured species, habitats, and ecosystems. 

• There appears to have been a lack of baseline data for the spill region. 

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Baseline studies should be conducted in all areas of oil and gas 

development. 

• Given the heavy application of dispersants over a long duration, the lack of 

water quality sampling seems particularly negligent. There does not appear 

to have been any rigorous sampling below the dispersed slick for the 

purpose of quantifying the levels of dispersed oil, to ensure that they did 

not exceed the expected range. 

• Information and data on spill trajectory and delineation was poorly 

captured and communicated. It is extremely difficult to find any plume or 

slick diagrams within the official incident documentation. 

• Water quality sampling was extremely limited and conducted over a short 

duration, after a significant delay. 

• Wildlife response activities appear to have been delayed, and wildlife 

impact surveys were not initiated until over a month after the spill was 

initiated. 

• Fisheries sampling methodologies and results have not been 

communicated. It is unclear whether the sampling has been initiated, what 

type of sampling will be conducted nor the level of analysis. It is important 

that fisheries sampling continue long enough to assess any potential 

impacts to larval or embryonic fish. 

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Table of Contents 

Executive Summary...............................................................................................3

Table of Contents ..................................................................................................6

Introduction .........................................................................................................8

Objectives ............................................................................................................8

Progress...............................................................................................................8

TOR 5: Adequacy of the Response to the Uncontrolled Release ...................................9

Summary of the TOR and Focus of the Inquiry ......................................................9

Discussion of the Issues Raised in the DOR ........................................................ 10

Background ............................................................................................ 10

Why the owner/operator chose to tackle the Uncontrolled Release in the way that 

it did? .................................................................................................... 10

Alternative ways of stemming or stopping the release of hydrocarbons ......... 11

Decision-making regarding selection of well control options .......................... 13

Relationship between the owner/operators and regulators and governments and 

impacts on response adequacy ................................................................. 14

Conclusions and Recommendations on TOR 5 ..................................................... 14

TOR 6. Assess the Adequacy of Regulatory Obligations ........................................... 15

Summary of the TOR and Focus of the Inquiry .................................................... 15

Discussion of the Issues Raised in the DOR ........................................................ 16

Adequacy of National Marine Oil Spill Contingency Plan to address worst 

case/blowout scenarios ............................................................................ 16

Balance between operators/agencies/public interest. Was the public interest 

served?.................................................................................................. 19

Interplay/coordination between agencies and regulatory regimes .................. 20

Whether the specific agency responses were appropriate. ............................ 20

Improvements to regulatory regimes for future incidents ............................. 20

If the location, magnitude, etc. of the spill had been different would the response 

authorities have had other options? ........................................................... 20

Implications for future oil & gas exploration operations ................................ 21

Conclusions and Recommendations on TOR 6 ..................................................... 22

TOR 7. Environmental Impacts and Monitoring Activities .......................................... 23

Summary of the TOR and Focus of the Inquiry .................................................... 23

Discussion of the Issues Raised in the DOR ........................................................ 24

Assessment of Operational Monitoring ............................................................... 25

Monitoring of Oil Distribution and Marine/Coastal Resources ......................... 25

Monitoring of Oil Character Fate and Effects Study ...................................... 26

Shoreline Assessment Ground Surveys ...................................................... 27

Monitoring of Dispersant Efficiency and Fate of Dispersed Oil ........................ 27

Wildlife Impact Monitoring ........................................................................ 28

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Scientific Monitoring Programs .......................................................................... 29

Marine Megafauna Aerial Assessment Surveys ............................................ 29

Shoreline Ecological Assessment Aerial Surveys .......................................... 29

Assessment of Fish Catch for Presence of Oil .............................................. 29

Assessment of Effects on Timor Sea Fish and Fisheries ................................ 30

Offshore Banks Assessment Survey ........................................................... 30

Shoreline Ecological Ground Surveys ......................................................... 30

Oil Fate and Effects Assessment ................................................................ 30

Conclusions and Recommendations on TOR 7 ..................................................... 31

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Montara Oil Spill Inquiry Analysis – 

Adequacy of Oil Spill Response 

Report to WWF-Australia 

February 2010 

Introduction 

This report was developed by Nuka Research and Planning Group, LLC under contract 

#122305 to provide WWF-Australia with analysis relevant to the Terms of Reference 

developed by the Montara Commission of Inquiry (the Inquiry) into the Uncontrolled 

Release of hydrocarbons at the Montara Wellhead Platform that commenced on 21 August 

2009. 

Objectives 

The objective of this report is to provide WWF-Australia with analysis of those Terms of 

Reference (TOR) that relate specifically to the adequacy of spill response and 

environmental impacts during the Montara Wellhead Platform Uncontrolled Release. The 

Terms of Reference related to the Adequacy of Response and Environmental Impacts are 

TOR 5 (Adequacy of Blowout Response), TOR 6 (Adequacy of Regulatory Obligations), 

and TOR 7 (Environmental Impacts Monitoring Activities). 

 Progress 

Nuka Research and Planning Group, LLC has reviewed documentation available via the 

Montara Commission of Inquiry1

 including all Submissions and supporting documentation, 

the Terms of Reference, and the Hearing Schedule and Policies established by the 

Commission of Inquiry. We have also reviewed related information and documentation 

available in the public domain, including the following: 

o Web log entries at skytruth.org, which include satellite imagery from the 

release,2

 

o Reports by the Department of the Environment, Water, Heritage, and the 

Arts relating to the environmental monitoring studies conducted,3

o The Australian Marine Safety Authority (AMSA) website documenting the 

 

1

 http://www.montarainquiry.gov.au/index.html 

2

 http://blog.skytruth.org/search/label/Timor 

3

 http://www.environment.gov.au/coasts/oilspill.html 

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Montara incident and response,4 

o The Australian Marine Safety Authority National Plan to Combat Pollution of 

the Sea by Oil and Other Noxious and Hazardous Substances,5

 and 

o The Australian Marine Oil Spill Centre (AMOSC) oil spill response resource 

inventory including their availability, location, and whether or not they were 

mobilized to the Montara response.6

It is important to recognize that this analysis was all developed based on review of 

written documentation. The authors were not firsthand participants in the Montara 

response, although we have firsthand experience in responding to a number of major 

U.S. oil spills. We have focused our analysis on issues related to spill response tactics 

and technologies, best practices, and recognized international standards for spill 

response. We have not provided comment on the TOR Inquiry issues that relate to 

agency performance or interactions among spill response agencies and organizations, as 

this is beyond our knowledge and experience base. 

TOR 5: Adequacy of the Response to the Uncontrolled Release 

Summary of the TOR and Focus of the Inquiry 

In the Issues paper published by the Commission of Inquiry, it was noted that the Inquiry 

developed TOR 5 to gain an understanding of: 

a. Why the owner/operator chose to tackle the Uncontrolled Release in the 

way that it did? 

b. Whether there were alternative ways of stemming or stopping the release 

of hydrocarbons and why these were not pursued? To what extent was the 

decision influenced by safety, commercial, environmental, technical or 

other considerations? 

c. Might decisions taken have been different in the event of a larger 

uncontrolled release of hydrocarbons, an alternative location, or if the 

consequences of that release had been thought to have been greater? How 

were decisions in that regard made? 

d. The effectiveness of the relationship between the owner/operators and 

regulators and governments, and how this relationship may have impacted 

the adequacy of the response to the Uncontrolled Release by the 

owner/operators. 

 

4

 

http://www.amsa.gov.au/Marine_Environment_Protection/Major_Oil_Spills_in_Australia/Montara_Wellhead/ind

ex.asp 

5

 http://www.amsa.gov.au/Marine_Environment_Protection/National_plan/ 

6

 http://www.aip.com.au/amosc/ 

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Discussion of the Issues Raised in the DOR 

Background 

An Uncontrolled Release, or well blowout, occurs when an uncontrolled flow of gas or 

fluids is released to the surface when the oil and gas reservoir pressure exceeds the 

hydrostatic pressure of the drilling muds and fluids contained in the wellbore, releasing oil 

into the atmosphere. When a blowout occurs, well control is necessary to stop the flow of 

oil or gas. Several approaches exist: additional surface control measures (well capping); 

ignition of the well blowout; subsea control measures; and drilling a relief well. 

Following the Uncontrolled Release, the operator of the Montara Platform, PTTEPAA, 

contracted with a well-recognized well control contractor (ALERT) to implement well 

control. ALERT’s first recommendation was for equipment and vessels to be sourced and 

dispatched to provide deluging capability (dousing the well with seawater to reduce the 

ignition risk). The ALERT Team arrived in Perth (from Singapore) on August 22, 2009 and 

after a brief assessment recommended, in addition to the use of deluge, the 

implementation of well control activities to include surface capping and relief well 

operations. On that same day, the National Offshore Petroleum Safety Authority (NOPSA) 

issued Prohibition Notice #0222, prohibiting any personnel from working at the WHP or 

West Atlas facilities. This prohibition cancelled any opportunity for surface well capping, 

which requires that personnel work at or near the drill rig and platform facilities. During 

the period of September 7 – 11, NOPSA expressed concern regarding the safety of 

personnel involved in deluge operations, and these activities were subsequently curtailed 

by PTTEPAA, with a few firefighting personnel and resources retained near the blowout 

site. 

Although PTTEPAA and ALERT began to implement the relief well plan immediately, 

response time was slowed due to the lack of availability of a drill rig to drill the relief well. 

Several nearby rigs were occupied and could not be released. The nearest available rig 

was the West Triton in Indonesia, which was transferred to Singapore to be prepared for 

the job. It was en route to the spill site on 27 August, 6 days after the spill began. It 

arrived at the spill site on 11 September, and began drilling on 14 September - 24 days 

after the start of the uncontrolled release. If a back-up drill rig had been required to be 

present in the area, this time could have been significantly reduced. Estimates of the oil 

release rate in this spill range from 64 to 480 tons per day, so each additional day of 

delay added a significant amount of oil to the environment. 

Why the owner/operator chose to tackle the Uncontrolled Release in the way 

that it did? 

PTTEPAA and ALERT considered several options for stemming the uncontrolled flow from 

the wellhead, initially recommending deluge followed by a combination of surface control 

measures and relief well drilling. Well ignition was not considered. A prohibition issued 

by NOPSA removed the possibility of surface well control activities, due to potential risks 

to personnel safety, leaving drilling a relief well as the only remaining option. 

A relief well intercepts the subsurface wellbore of the out-of-control well. A relief well is 

often not the first or sole choice to control the well because of the time it takes to 

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mobilize a relief well rig into the area where the blowout is occurring. If a rig is on 

location or nearby, it may be possible to shut down drilling operations to aide in the 

blowout response. If there are no nearby rigs capable or willing to assist in the response 

operations, then it will take substantial time to move a second rig into the area. In the 

interim, other well control operations may be initiated, although this was not the case in 

the Montara release. 

Once the relief well drilling rig is moved into the area, it still can take days to weeks to 

drill a well into the subsurface to a depth sufficient to intercept the wellbore that is 

actively blowing out. This was the case during the Montara release, where several 

unsuccessful attempts to drill a relief well occurred before they were successful. Once the 

wellbore is intercepted by the relief well, fluids are pumped into the well to control the 

blowout. Depending on the nature of the blowout these fluids may consistent of brine, 

drilling mud, or polymers; these fluids are often referred to as “kill fluids” because they 

serve to “kill” the well blowout. When the blowout is killed, the well may then be closed 

in. 

The benefit of choosing to drill a relief well was that it presents the lowest safety risk to 

personnel. The drawback of relief well as well control is the amount of time required to 

drill the well. In the Montara incident, this was exacerbated by the long distance that the 

drill rig had to travel before it reached the spill site and by challenges in drilling the well. 

If a more proximate drilling rig had been made available to the incident, the 3-week 

mobilization timeframe may have been reduced; however, it is impossible to speculate as 

to whether another rig would have had quicker success in drilling a relief well. 

The unanswered question in the Inquiry submissions is whether or not it would have been 

feasible to intentially ignite the well to control the blowout. It is obvious, since the 

platform did in fact catch fire during the incident, that there were sufficient flammable 

vapors present so support voluntary well ignition. PTTEPAA’s submission does not discuss 

voluntary well ignition, therefore it is unclear whether this option was considered and 

dismissed, or whether it was not considered at all.

Voluntary well ignition is a rare occurrence, and certainly presents safety hazards. 

However, the major drawback from the perspective of many operators is the fact that 

voluntary well ignition results in significant financial losses, as the fire typically damages 

or destroys the well, rig, and/or platform. If voluntary well ignition was a viable option 

for the Montara Relase but was dismissed due to financial concerns, then the decision to 

use a relief well bears closer scrutiny. Otherwise, there do not appear to have been other 

viable options for well control during this incident. Most of the documentation available 

through the Inquiry suggests that personnel safety was the primary driver in most of the 

decision-making regarding well control, and this is consistent with international best 

practices. 

Alternative ways of stemming or stopping the release of hydrocarbons 

There are a few alternative approaches to drilling a relief well: surface control (well 

capping), subsea measures, and voluntary ignition. The Inquiry Submission by PTTEP on 

TOR #5 states that the well control measures that were considered for the Montara 

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incident were: deluge, well capping, and subsea options. Of these, deluge was conducted 

during the first few weeks of the response. Well capping and subsea options were both 

dismissed for various reasons, discussed below. Voluntary ignition was not considered 

and is not addressed in the PTTEP submission. 

Capping Option

In order to cap and control a well, the well control specialist must be able to access the 

wellhead to either repair the blowout prevention system (BOP) or remove the defective 

BOP to control the well pressure. Therefore one of the first challenges, and often the most 

time consuming, is to remove the rig structure and wellhead debris from around the well, 

while it is actively blowing out hydrocarbons and drilling muds and at risk of possible 

explosion. In some cases, the wellhead can be exposed by clearing away the damaged 

rig or offshore platform components; however, in some cases rig removal may also be 

required. 

Well capping requires specially trained personnel and specialized equipment to operate in 

these hazardous conditions. Compared to onshore well capping, controlling a blowout on 

an offshore platform presents additional challenges. The PTTEP submission summarizes 

the complications and challenges that would have been involved in capping the H1 Well. 

PTTEPAA ruled out the Capping Option for the following reasons: fire risks, risks of 

injuries or fatalitites, and NOPSA prohibition on personnel operations near the West Atlas 

and WHP. 

Subsea Options

PTTEPAA considered two options to use sub-sea technology to control the blowout: 

fabricate a machine to crush the casing and block off the well flow; or cut the casing and 

cap it underwater. Both options were dismissed within 3 weeks of the release for several 

reasons, again linked mostly to safety. Cutting the casing was also considered to have a 

lower chance of successfully controlling the well than other options. 

Voluntary Well Ignition 

Voluntary Well ignition may be used during oil and gas blowouts, especially if there is a 

toxic component to the released hydrocarbons. Voluntary well ignition is differentiated 

from the spontaneous well ignition that may occur during a blowout because the operator 

chooses to ignite the well as a means of controlling the release. 

The explosive limit of differing blowout flows varies with chemical composition. There is a 

minimum ratio of hydrocarbon vapor to air below which ignition will not occur; however, if 

hydrocarbons are released near the wellhead, gas will be present in the air, and some of 

the oil will flash evaporate, forming an aerosol of liquid droplets and vapor. Heavier 

hydrocarbon liquids that do not flash evaporate will continue to pool around well and 

release vapors. Hydrocarbon vapors will mix with air and form a combustible vapor cloud. 

Once this explosive vapor is exposed to an ignition source, combustion will start and a 

flame front will propagate through the flammable zone. 

The high level of concern regarding unintended ignition during the Montara release, and 

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the fact that spontaneous ignition ultimately did occur, both indicate that there were 

sufficient ignitable vapors present to support voluntary well ignition. However, this option 

is not discussed in PTTEPAA’s submission, therefore it appears that this option was not 

considered. 

Significant personnel and property safety issues are associated with well ignition during 

an ongoing (uncontrolled) well blowout, and operators are often reluctant to voluntarily 

ignite a well since it may result in complete loss of the well, rig, platform or facility. From 

a spill impact perspective, voluntary well ignition may reduce the overall spill volume to 

water, although it creates air pollution in the form of the smoke plume. 

If well ignition was identified by PTTEPAA in their oil spill contingency plans as a viable 

option for mitigating a well blowout, than it is important to raise the question as to why 

this response option was not considered. It is possible that safety considerations, which 

were a major component of the response decision-making, would have precluded this 

option entirely. However, there is not enough information in the publicly available 

documentation to understand whether or not well ignition was ever considered. It has 

been our observation in US offshore oil and gas operations that operators often identify 

voluntary well ignition as a viable response option in their contingency plans, but almost 

never apply this option, in large part because of the major financial losses they would 

suffer in the event of complete loss of the well, rig, and/or platform. 

Decision-making regarding selection of well control options 

Most of the documentation available through the Inquiry suggests that personnel safety 

was the primary driver in most of the decision-making regarding well control. The fact 

that there were such significant delays in mobilizing a rig to drill the relief well and then 

successfully drilling that well do not appear to be linked to any specific parameters of the 

blowout (location, size, etc.) although the distance that the relief drilling rig was required 

to travel to the spill site did play a part in the overall delays. 

It is difficult to speculate as to whether a more proximate drilling rig might have been 

released to the Montara Release if it had occurred in a different location (i.e. closer to 

shore) or if the blowout volume had been more significant. Oil and gas exploration and 

production plans are developed based on the assumption that all available and necessary 

resources would be brought to bear to clean up a spill, regardless of its size or location. 

The problem with relief wells as a source control measure is that unless a drilling rig is 

situated nearby and the operator has immediate access to that rig, the operator must 

work through locating and then negotiating the release of an available drill rig, and that 

rig often must travel significant distances to the spill location. 

A review of other major oil well blowouts worldwide show that the controlling the well is 

often a problematic and time-consuming prospect. For example, the largest blowout in 

history, the 1979 Ixtoc I incident in Mexico, took nine months for the well to be 

completely shut in, with two relief wells drilled. A 1987 natural gas well blowout in Cook 

Inlet, Alaska required nearly 8 months to control, again due to delays in mobilizing rigs 

and drilling relief wells. 

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Relationship between the owner/operators and regulators and governments and 

impacts on response adequacy 

Based on a review of the available documentation, there do not appear to have been any 

major deficiencies or disconnects between the operators, AMSA, and AMOSC that 

impacted the adequacy of the response. 

It is important to try to understand whether regulators held the operators to the 

appropriate standard with respect to the well control component of the response. 

According to the DEWHA Submission, Montara’s oil spill contingency plan (OSCP) did not 

commit to a timeframe for controlling a well blowout. It is unclear, not having reviewed 

the OSCP firsthand, whether it committed to considering other types of control, such as 

voluntary ignition. If so, then the authorities may have had some justification to ask 

PTTEPA to consider voluntary ignition, which might have allowed the release to be 

controlled more quickly. 

Conclusions and Recommendations on TOR 5 

• The decision to drill a relief well was made on the basis of personnel safety 

considerations. Several other options were considered and dismissed for 

seemingly valid reasons. However, voluntary well ignition does not appear 

to have been considered. 

• The amount of time that lapsed between the initiation of the release and 

the drilling of a relief well (10 weeks) is not atypical. It is not uncommon 

for relief well operations to require considerable time, which is why relief 

wells are not typically the first or sole choice to control the well. 

• Delays in the relief well were caused both by the time required to mobilize 

and transport the rig (3 weeks) and the time required to successfully drill 

the well. The first timeframe could have been reduced if a rig had been 

locally available closer to the spill site. 

• The Inquiry should clarify whether voluntary well ignition was considered as 

an alternative to a relief well. If it was not, the Commission should explore 

whether this option was dismissed due to financial considerations on the 

part of the operator. 

• The Commission should review the operators’ exploration plans and oil spill 

contingency plans to determine whether these plans made any specific 

commitments regarding blowout control resources or decision-making. If 

so, then this represents a need for stricter oversight. 

• The Commission should consider whether the regulatory agencies had the 

authority to intervene in the process of securing a drilling rig in a more 

timely manner. If such authority was present but un-exercised, this may 

be cause for concern. If such authority does not exist, it might be an area 

to improve regulations. 

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TOR 6. Assess the Adequacy of Regulatory Obligations 

Summary of the TOR and Focus of the Inquiry 

The Commission has identified the following key legislation and regulations that appear to 

bear on the response to the Uncontrolled Release: 

a. The National Marine Oil Spill Contingency Plan, managed by AMSA. 

b. The Offshore Petroleum and Greenhouse Gas Storage Act 2006. 

c. Schedule 3 to the Offshore Petroleum and Greenhouse Gas Storage Act 

2006 and the Petroleum (Submerged Lands) (Management of Safety on 

Offshore Facilities) Regulations 1996. 

d. The conditions of approval of the Montara Field Development under the 

EPBC Act. 

The Commissioner wishes to understand the interplay between the actions of the 

owner/operator and the various regulators over the period and how this affected the 

options available to the owner/operator. 

a. Whether the National Marine Oil Spill Contingency Plan adequately 

envisaged an uncontrolled release of hydrocarbons of the magnitude and 

duration of the Uncontrolled Release and in such a remote location in 

Commonwealth waters, or at least provided an adequate framework that 

could be adapted effectively to cope with differing events. 

b. The extent to which the response should have been left to the 

owner/operator, or should have been subject in certain circumstances to 

direction by regulators. In other words, to what extent does the existing 

regulatory regime strike an appropriate balance between the commercial 

interests of the owner/operator compared with broader public interest 

considerations? 

c. To what extent did the decisions by the owner/operators and regulators 

alike comprehend the overall picture, especially since there are a number of 

regulators, with differing responsibilities? What steps did regulators take to 

ensure that they had a shared understanding of emerging events? And to 

what extent did regulators work separately or jointly with the 

owner/operator to ensure an appropriate response? To what extent could 

other response mechanisms available within the regulatory regime have 

been used if the attempts to stop the Uncontrolled Release had continued 

to fail, and at what stage would these mechanisms have been 

implemented? 

d. Whether the responses from the NT Department of Regional Development, 

Primary Industry, Fisheries and Resources; the Commonwealth Department 

of Resources, Energy and Tourism; the Commonwealth Department of the 

Environment, Water, Heritage and the Arts; NOPSA; and AMSA were 

appropriate. 

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e. Whether any steps taken by other regulatory agencies to respond to the 

incident, including the Western Australian Department of Fisheries and the 

Australian Fisheries Management Authority, were appropriate. 

f. To what extent might the regulatory regime and specific obligations under 

the regulatory regime be improved upon in order to more effectively deal 

with future incidents? 

The Inquiry also seeks to understand the extent of consultation undertaken by regulatory 

agencies and between those agencies and the owner/operator (or other parties) in 

determining the chosen course of action. 

a. If the Uncontrolled Release had been of a greater magnitude, if the location 

of the incident had been different (including its proximity to other response 

equipment), or if the environmental or other consequences of the 

Uncontrolled Release had been greater, were there alternative avenues that 

regulators may have been able to pursue with the owner/operator (and 

other parties) to stem or plug the Uncontrolled Release? 

b. Was the response appropriately determined between regulators and 

owner/operators, especially in view of the fact that public interest 

considerations may not necessarily align with commercial considerations or 

the specific interests of individual regulators? 

c. Alternatively, if there were no other appropriate alternatives, what 

implications might this have for the way offshore petroleum developments 

should be regulated in the future? For example, might consideration need 

to be given to a more searching examination of what is proposed for 

offshore petroleum developments at the preapproval stage (covering 

environmental, safety or operational considerations)? 

Discussion of the Issues Raised in the DOR 

Adequacy of National Marine Oil Spill Contingency Plan to address worst 

case/blowout scenarios 

The National Marine Contingency Plan plans for three levels of incidents, including Tier 3, 

or large spills of over 1,000 tons. The level of planning in place in Australia is on par with 

that of the US, Canada, and the EU. Australia’s spill response program integrates 

multiple agencies and jurisdictions, and this is a common arrangement in oil spill 

response in nearly any nation. Large oil spills nearly always involve multiple agencies, 

organizations, and jurisdiction. There are a number of tools and agreements in place in 

Australia to facilitate these interactions. In our professional opinion, the fact that the 

Montara spill occurred and the delays in drilling the relief well were not directly related to 

any deficiencies in the National Marine Oil Spill Contingency Plan. 

The response options utilized during the Montara Release favored chemical dispersants, 

which are a group of chemicals sprayed or applied onto oil slicks to accelerate the process 

of natural dispersion. They are usually used in oil spill response when it is desirable to 

reduce the amount of floating oil to minimize damage to shorelines, wildlife, and other 

sensitive resources. Chemical dispersants are most commonly used for offshore or 

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nearshore spill responses, often when conditions are too rough to conduct mechanical 

recovery. Chemical dispersants require a certain level of mixing energy to work 

effectively; they are least effective during calm conditions. The stated goal of dispersant 

use during the Montara Release was to reduce the likelihood of floating oil impacting on 

marine parks of Ashmore and Cartier Reefs. 

AMSA's submission to the Inquiry states that the "window of opportunity" for dispersant 

use "may be as little as only a few hours. If the conditions are favourable, as in this 

incident, the window of opportunity may be up to two days." However, no dispersant was 

sprayed until two days after the spill began. If this release had been a large 

instantaneous spill (as opposed to a continuing release), AMSA's resources may have 

been unable to effectively mobilize a dispersant response within the window of 

opportunity. 

The first response equipment to arrive on the scene was a C-130 Hercules helicopter from 

Singapore, which sprayed dispersant from 2 days post spill to 4 days post spill. Single 

engine aircraft were judged to be more effective for the purpose, and they took over the 

dispersant response for the next nine days. After that, dispersant was sprayed from 

offshore support vessels with directions from aircraft, targeting concentrated patches of 

oil, and continuing operations over two months beyond the start of the spill. Six different 

dispersant chemicals were applied; all are approved under the National Plan, although it 

is unclear whether the National Plan Dispersants guidance ever envisioned a spill where 

multiple dispersants would be applied over time. 

In deciding to use dispersants, AMSA determined that “the National Plan approved 

dispersants will likely have success on the unweathered fresh oil being released from the 

platform.” AMSA conducted a Net Environmental Benefit Analysis (NEBA) to aid in 

dispersant use decision-making, and DEWHA provided input into this process regarding 

environmental impacts. DEWHA recommended using dispersants only on fresh oil slicks 

and in conjunction with mechanical collection, and away from coral habitat or major 

marine megafauna. NEBA is a common decision tool used in spill response, although it 

has been criticized in the context of dispersants because it does not always take into 

account the potential acute and long-term toxicity, particularly in a case such as Montara 

where the applications were ongoing for such a long duration. 

Continuous dispersant operations is a plausible approach to an offshore blowout, where 

fresh oil is continuously being released. However, the decision to apply dispersants can 

have implications on the potential success of other response options, like on-water 

mechanical recovery. Once a slick is chemically dispersed, it will be much more difficult 

to corral, concentrate, and recover the remaining un-treated oil. And on-water recovery 

operations cannot be safely conducted in an area where aerial dispersant spraying is 

ongoing. Because the response favored dispersants so heavily, there may have been 

some lost opportunity for mechanical recovery. 

Oil recovery vessels did not enter the area until 5 September, over two weeks from the 

start of the spill. This is not completely in alignment with the National Plan, which 

designates dispersants as a secondary response option, with mechanical recovery of oil 

the preferred option. It is important to understand the decision-making that led to a 

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dispersant-dominated response approach; however, there is little information in the 

Submissions that inform on this process. Because dispersants are a much less expensive 

and less labor-intensive response option than mechanical recovery, it is relevant to 

consider whether dispersants were emphasized to minimize cleanup costs. The Inquiry 

should attempt to determine what the driving factors were in relying on dispersants over 

other clean-up methods. 

As discussed under TOR 7, the National Plan does not provide the same framework for 

environmental monitoring and natural resources damage assessment as, for example, the 

US system provides. Some of the delays in implementing monitoring and weaknesses in 

the monitoring programs (discussed under TOR 7) might be addressed in the future if the 

Australian requirements for spill environmental monitoring were strengthened to the level 

of the Natural Resources Damages Assessment (NRDA) requirements in the US under the 

Oil Pollution Act of 1990 and the US National Contingency Plan. 

DEWHA’s comments on TOR 7 also note that the environment plan developed by Montara 

“did not foresee the need for immediate or long term environmental monitoring in the 

event of an oil spill. While this would not have prevented or foreseen the management of 

risk, it would have acted as a contingency measure, providing baseline and long-term 

monitoring to assist in response operations and in identifying and addressing impacts. 

DEWHA intends to impose such a condition in future oil and gas approval decisions as 

part of its more conservative approach.” 

There are several facets of this incident and the response that may have broader 

planning/policy implications, some of which may relate to the National Plan and/or future 

operator oil spill plans or permits. 

National requirements for relief well drilling could be implemented to require that 

operators have a rig on standby to drill relief wells, thus avoiding delays like the initial 

delay at Montara while the rig was mobilized from Indonesia to Singapore and finally to 

the spill site. The National Plan could be amended to provide additional authority to spill 

control agencies to intervene when there are delays in securing a drilling rig, if they do 

not currently hold that authority. 

The Dispersant Guidelines under the National Plan includes a list of approved dispersants 

based on their estimated effectiveness from laboratory tests and their chemical 

composition/toxicity (again based on laboratory tests). Beyond the initial laboratory 

toxicity testing, there is no further requirement for field monitoring for toxicity impacts. 

In a case like the Montara, where there were several weeks’ worth of ongoing dispersant 

applications and where 6 different dispersant chemicals were applied, this would have 

been at the very least an opportunity to collect field data on toxicity. It appears that 

there were some dispersant operations in the vicinity of shallower bank/reef areas, and it 

would have been particularly useful to monitor those areas, which are less appropriate for 

dispersant use than open water areas. 

The National Plan would be improved by including requirements that toxicity 

testing/monitoring be conducted concurrent with any future dispersant applications. The 

National Plan should also specify whether it is appropriate for multiple dispersant 

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chemicals to be applied to the same spill. While it appears that the different chemicals 

were applied at different times during the spill, the National Plan does not appear to have 

considered whether there might be aggregate toxicity issues associated with using 

multiple chemicals, or other unforeseen consequences. 

The National Plan could include stricter parameters for requiring responsible parties to 

initiate and fund environmental monitoring studies, and could provide guidance on 

acceptable sampling procedures and protocols. Operator plans could be required to 

include both baseline studies pre-operation and robust scientific monitoring if a release 

should occur. 

Balance between operators/agencies/public interest. Was the public interest 

served? 

The Commission appears to be interested in whether or not the balance between the 

operators and the regulatory agencies is adequate to serve the public interest, which in 

this case we presume to be minimizing the adverse impacts of the oil spill. A key factor 

in making this determination lies not in the interactions at the time of the incident, but in 

the governmental oversight that went on during the planning stages of this exploration 

operation. The operators are all required to develop oil spill contingency plans that 

outline how they would manage a blowout or other emergency. The oil spill contingency 

plan for Montara/West Atlas does not appear to be in the public domain. However, it 

would be worthwhile for the Commission to consider whether those plans set out any 

criteria for selection of well control techniques, and then assess whether those criteria 

were followed. The plan may also establish a timeline for drilling relief wells; in many 

areas of the US, operators are required to have a relief well drilled within 30 days. Did 

the operators set any time limit on drilling a relief well? If they did make some 

commitment in their plans that they did not meet in the real world, then the planning 

process (and regulatory oversight of industry planning) is not serving the public interest. 

Also, the decision to favor dispersants over mechanical recovery resulted in a higher total 

volume of the oil remaining in the marine environment, in various states. Because 

dispersants were used so persistently during the response, very little of the oil released 

during the blowout was actually recovered. AMSA estimates are that approximately 433 

tons of the total spill were recovered. This means that the rest of the crude oil has either 

evaporated (possibly leaving behind waxy residues that would persist in the 

environment), remained in the environment untreated, or has been chemically dispersed 

into the water column, where it may have other toxicity impacts. Dispersant and 

dispersed oil toxicity are issues associated with dispersant application, and these are 

discussed under TOR #7. 

Perhaps the most important consideration here is whether or not there was any 

mechanism provided for stakeholder input into response decision-making. A review of 

the incident documentation does not appear to show that there was any level of 

stakeholder input or review. Comments from one of the fishing organizations (WAFIC 

Submission) states that they were denied opportunities for government consultation. 

Submission comments from the University of West Australia cite a lack of transparency in 

the communication of environmental monitoring and sampling data and results. There 

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are mechanisms in place in other nations such as Regional Stakeholder Committees in the 

US where either ad hoc or standing bodies of citizens and stakeholders are provided with 

a mechanism to communicate their priorities and concerns to response decision-makers. 

As discussed under TOR 7, delays and shortfalls in environmental monitoring may make it 

difficult for the public and the government to fully understand the extent of the spill’s 

impacts, which in turn will compromise the ability to remediate those impacts and 

restored injured species, habitats, and ecosystems.

Interplay/coordination between agencies and regulatory regimes 

There does not appear to be any clear cut examples of where jurisdictional conflicts 

reduced the response effectiveness. Firsthand participants may provide better insight 

into this issue. 

Whether the specific agency responses were appropriate. 

As discussed above in the context of public interest, there are a few components of the 

spill response that bear further scrutiny: consideration of alternate well capping 

technologies (discussed in TOR 5); selection of spill response technologies (specifically 

the emphasis on dispersants over mechanical clean-up); environmental monitoring 

(discussed under TOR 7); and delays in mounting both an on-water response and 

environmental monitoring. Lack of adequate oversight or management by one or more of 

the involved agencies may have contributed to any or all of these situations. 

Improvements to regulatory regimes for future incidents 

In order to provide meaningful recommendations regarding improving regulatory regimes 

for future incidents, it is important to first get some consensus on what the successes and 

failures of the response were. Based on our review of the documentation, we believe the 

major response failures/challenges appear to have been: 

• Delays in establishing well control; 

• Insufficient on-water recovery operations; 

• Relatively low amounts of oil recovered; 

• Lack of dispersant toxicity monitoring; and 

• Delays in initiating environmental monitoring and sampling programs. 

There may be regulatory fixes for some of these issues. Stricter regulations and 

requirements for well capping/drilling relief wells may be effective. With most of the 

other response issues, the solution may not lie in new regulations, but in developing 

better mechanisms for ensuring that response decisions address stakeholder concerns 

and considerations. This might be done through development of stakeholder review 

committees or similar bodies. 

If the location, magnitude, etc. of the spill had been different would the 

response authorities have had other options? 

If the spill had occurred in closer proximity to major response resource centers, then 

obviously the mobilization and deployment of equipment, vessels, aircraft, and personnel 

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would have been quicker. This question seems to focus in again on whether there might 

have been a different well control solution if the spill scenario (location, size, severity) 

had been different. We can only assume that there has been some speculation that initial 

reports underestimating the release volume and/or the fact that the release happened so 

far offshore (and away from the public eye) somehow led the operators and regulators to 

somehow delay the response? This is beyond our knowledge base, but if the Inquiry 

shows that the response efforts were anything less than full-scale effort on the part of all 

parties, then there has been some negligence. 

An uncontrolled well blowout is a worst case spill, regardless of whether it is releasing 60 

or 400 tons a day. While the distance from shore certainly plays into decisions about 

what types of cleanup operations to conduct, it should not have any impact on the top 

priority, which would be to bring the blowout under control. If the platform had been 

located elsewhere, it may have been in closer proximity to another rig that could have 

drilled a relief well more quickly. The other well control factors discussed under TOR 5 

were more safety related and would apply in most situations. The Inquiry should 

consider whether any effort was withheld early on in the response, for any reason, but 

particularly because of an underestimate of the severity of the release. It is equally 

important to ensure that PTTEP met any spill response obligations made in their oil spill or 

operational plans. 

The key issue that the Commission seems to be concerned with here is source control; 

however, the parameters discussed (spill location, severity) typically relate more to 

decisions about spill cleanup tactics, sensitive area protection, and wildlife response than 

they do to source control. Response managers will typically utilize different response 

techniques, equipment, and tactics based on the spill location, trajectory, type of product, 

on-scene conditions, and size. Source control decisions may be influenced by the 

particular circumstances of the blowout, but regardless of the size of the blowout, the 

priority should be to bring it under control as quickly as possible. It is relevant for the 

Inquiry to consider whether voluntary ignition of the well might have provided a more 

effective source control option, as discussed under TOR 5. It is important to ensure that 

the decision-making on well control did not prioritize the well infrastructure over the 

potential for environmental harm. 

Implications for future oil & gas exploration operations 

There are a number of implications to future oil and gas explorations that relate back to 

prevention of future incidents, and these are being covered in the analysis conducted by 

Harvey Consulting, LLC. 

From a response perspective, the major issue here is well control. The other spill 

response planning and policy considerations reach beyond oil and gas exploration to oil 

spills from other sources. However, the unique aspect of oil and gas exploration 

operations is the potential for a loss of well control and the need to be able to regain 

positive control of the well as quickly as possible. This can be achieved through enhanced 

regulations, more diligent oversight, and periodic field verification of well control 

technologies. No blowout prevention technology will be effective 100% of the time, but 

the government and operators should maximize their efforts to prevent blowouts, 

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because as the Montara illustrated, responding to them can be quite challenging. 

As discussed under TOR 7, environmental monitoring was not an immediate priority 

during the response, and there was no clear understanding regarding PTTEPA’s role or 

responsibility in conducting environmental monitoring. DHEWA’s submission suggests 

that future exploration permits include the requirement that the operator commit to 

carrying out the required environmental monitoring and impacts studies in the event of a 

release. 

A broader question is whether the risks clearly illustrated by the Montara Release 

outweigh the benefits of future exploration activities. In the US, offshore oil and gas 

development plans often cite the extremely low probability of a well blowout, and this low 

probability is typically factored into early environmental assessments of the potential 

impacts from development projects. The Montara Uncontrolled Release demonstrates 

that low probability is not zero probability. Any oil drilling operation can experience a 

blowout, and when it occurs, it may take weeks or months to control. 

Conclusions and Recommendations on TOR 6 

• The National Plan is consistent with other similar national plans in North 

America and the EU. 

• National well control standards and requirements for operators should be 

reviewed. Operators who have identified a relief well as a blowout control 

measure could be compelled through regulation or permit to have a rig on 

standby to drill relief wells, thus avoiding delays like the initial delay at 

Montara while the rig was mobilized from Indonesia to Singapore and 

finally to the spill site. 

• The response techniques used during the response were primarily 

dispersants, and very little oil was mechanically recovered with boom and 

skimmers. While there does not appear to have been any violation of 

national policy, the heavy reliance on dispersants is not entirely consistent 

with the stated national policy that mechanical recovery is the preferred 

method of clean-up. The Inquiry should consider the decision-making 

process that led to a dispersant-based response. 

• The National Plan policies on response technique selection should be 

reviewed to provide additional clarity about the use of dispersants vs. 

mechanical recovery for offshore spills. 

• The National Plan does not provide an equivalent framework for 

environmental monitoring as other nations. The US Natural Resource 

Damage Assessment requirements should be reviewed as a possible model. 

• The National Plan policies on Dispersant Application should be reconsidered regarding the potential for combinations of various dispersant 

chemicals to pose additional environmental toxicity. The national 

dispersant policy should also include some testing for environmental 

toxicity, particularly in instances where such a large volume of dispersants 

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are applied over such a long period of time. 

• Decisions about response technique selection were made without public 

input or review. The National Plan could be modified to include a better 

mechanism to allow either ad hoc or standing bodies of citizens and 

stakeholders to communicate their priorities and concerns to response 

decision-makers. 

• The major future implication of this incident, from a response perspective, 

relates to well control. It is possible to develop stricter parameters to 

ensure that future operations proceed with a more reliable mechanism for 

well control, such as a second drill rig on standby to drill a relief well. 

• The Montara drilling plans did not adequately consider the need for 

environmental monitoring in the event of a spill. Future oil and gas 

exploration operations should include stricter parameters for environmental 

monitoring and sampling, including requirements for baseline studies, and 

operators should have a clear understanding of the types of environmental 

monitoring studies that should be initiated and conducted during and after 

a release. 

• The most important implication of this incident is the fact that there is no 

blowout prevention technology that can be 100% effective; the risk of 

another catastrophic blowout cannot be removed unless oil and gas 

exploration is ceased. 

TOR 7. Environmental Impacts and Monitoring Activities 

Summary of the TOR and Focus of the Inquiry

The Inquiry also seeks submissions on the adequacy of the environmental response, 

including: 

a. The adequacy of the “Monitoring Plan for the Montara Well Release Timor 

Sea as agreed between PTTEP Australasia and the Department of the 

Environment, Water, Heritage and the Arts, 9 October 2009” (the 

Monitoring Plan) (see http://www.environment.gov.au/coasts/oilspill.html). 

Relevant to this issue is the fact that: 

o The Monitoring Plan includes an Operational Monitoring Programme, 

with the monitoring to be undertaken by AMSA in accordance with 

the National Marine Oil Spill Contingency Plan. 

o The Monitoring Plan also incorporates a Scientific Monitoring 

Programme, which will be managed by the owner/operator. Specific 

studies under this Programme will require approval by the 

Department of the Environment, Water, Heritage and the Arts prior 

to initiation. 

b. How effective was the Operational Monitoring Programme and what lessons 

have emerged? 

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c. Is the Scientific Monitoring Programme adequate; and are there worthwhile 

enhancements that could be made to it? 

d. It is noted that the Department of the Environment, Water, Heritage and 

the Arts is required to approve study proposals under the Scientific 

Monitoring Programme, which will then be managed by the owner/operator. 

What role will the Department of the Environment, Water, Heritage and the 

Arts be taking in assessing or reviewing the veracity of the studies that are 

being commissioned? What will be the Department’s role in determining 

how the studies might be modified or evolve as circumstances change over 

time? Will there be independent peer reviews of the studies? 

e. What public reporting is envisaged to flow from the Operational and 

Scientific Monitoring Programmes? 

f. What, if any, other action is envisaged following receipt of outcomes from 

the Operational and Scientific Monitoring Programmes? 

Discussion of the Issues Raised in the DOR 

An Environmental Monitoring Plan was published jointly by DEWHA and PTTEPA in 

October 2009, and it outlines the ongoing monitoring activities as well as future plans. 

The Environmental Monitoring Plan focuses on two areas: Operational and Scientific 

Monitoring. Operational Monitoring (Type I) which is focused on providing information 

that assist with executing the spill response in a manner that minimizes adverse 

environmental impacts. The Scientific Monitoring (Type II) involves data collection for 

short and long term monitoring of environmental impacts. The primary distinction 

between Type I and Type II monitoring (which may overlap in terms of methodologies 

and data collection/analysis) is that Type I monitoring provides rapid results that can be 

fed into the incident decision-making process to influence the response. Type II 

monitoring is less time-critical, and while the data may be used to determine overall spill 

impacts or assess damages, it is typically not considered in the context of day-to-day 

response operations. At a certain point in a large spill, Type I monitoring may become 

Type II monitoring, as the response winds down. 

The Environmental Monitoring Plan called for five areas of Operational Monitoring: 

• Monitoring of Oil Distribution and Marine/Coastal Resources 

• Monitoring of Oil Character Fate and Effects 

• Shoreline Assessment Ground Surveys 

• Dispersant Efficacy and Fate of Dispersed Oil Monitoring 

• Wildlife Impact Monitoring 

The Scientific Monitoring Plan included seven proposed studies: 

• Marine Megafauna Aerial Assessment Surveys 

• Shoreline Ecological Assessment Aerial Surveys 

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• Assessment of Fish Catch for Presence of Oil 

• Assessment of Effects on Timor Sea Fish and Fisheries 

• Offshore Banks Assessment Survey 

• Shoreline Ecological Ground Surveys 

• Oil Fate and Effects Assessment 

Assessment of Operational Monitoring 

DEWHA’s Submission states that their key concerns for operational monitoring were to 

determine the effect of the oil and response operations on water quality, habitats and 

wildlife through the following: 

• profile of the oil, dispersants and oil-dispersant mixes in the water column 

(including vertical and horizontal distribution); 

• fate of the oil, dispersants and oil-dispersant mixes; and 

• timeframe in which impacts to wildlife, islands, reefs, shoals and coasts 

may occur. 

As discussed below, the overall operational monitoring efforts appear to have been 

somewhat uneven and not well reported in the public domain. The Submission by the 

University of Western Australia characterized the monitoring efforts as “tardy and 

superficial.” The biodiversity studies conducted by WWF Australia provided more in-depth 

information and analysis than the spill-sponsored monitoring reports. And the spill 

delineation done by skytruth.org using satellite imagery appears to have been more 

comprehensive and accurate than the slick delineation by AMSA. More timely and 

intensive operational monitoring should have been conducted and vigorously reported to 

the public. During the M/V Selendang Ayu oil spill in the US Aleutian Islands, water 

quality and fisheries sampling programs and results were quickly communicated out to 

the public; this type of transparency is critical during a large spill.7

 

Monitoring of Oil Distribution and Marine/Coastal Resources 

The Monitoring of Oil Distribution and Marine and Coastal Resources has included 

trajectory modeling and aerial and on-water surveillance of the release. This study is a 

typical component of any spill response, where ongoing reconnaissance is conducted to 

delineate the slick, direct response resources, and monitor for shoreline or wildlife 

impacts. According to the DEWHA submission, results from this study were provided to 

DEWHA and used to target wildlife monitoring and response operations. This information 

should be provided for review by the Commission of Inquiry, particularly in light of the 

biodiversity studies conducted by WWF Australia, which showed significant concentrations 

of marine mammals, reptiles, and birds in the vicinity of oil slicks. 

Interestingly, unlike major US oil spills in which the authors have participated, where GIS 

maps are frequently produced and published to summarize information about spill 

location and impacts, we could not readily locate such mapping for the Montara release. 

 

7 http://www.dec.state.ak.us/SPAR/PERP/RESPONSE/SUM_FY05/041207201/041207201_index.htm 

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The best source of spill imagery seems to come from the Skytruth web log. It is likely 

that this information was captured and mapped in some format, but it does not appear to 

be available for review. By comparison, during the M/V Selendang Ayu spill response in 

the US Aleutian Islands, daily maps were produced to show the results of aerial 

overflights.8

 The Inquiry should review the overflight maps that were produced during 

the incident, and should also compare that information to the Skytruth.org satellite 

imagery. There is a significant discrepancy between the estimated slick size offered by 

AMSA (6,000 km2

) as compared to the Skytruth estimate (10-25,000 km2). 

Monitoring of Oil Character Fate and Effects Study 

This study incorporated the collection of oil samples from the sea and any impacted 

shoreline areas. DEWHA describes this study as including water and oil sampling and 

monitoring, but recognized that their efforts to determine the horizontal and vertical 

distribution of oil and oil dispersant mixes was hampered by contamination of samples. 

only four dispersant operations were monitored for oil-dispersant mix distribution and of 

those operations, three different dispersants were applied. 

Of the small number (11 total) of water samples collected and analyzed, two were taken 

from beneath oil slicks, and one from beneath a slick of "white waxy droplets." One of 

the samples taken beneath an oil slick showed TPH 0.8-0.12 at all measured depths (1, 2, 

3, 5m), while TPH was undetectable in all other samples. Another study looked at 6 

sampling locations in the Timor Sea, with no hydrocarbons detected. A final study 

sampled locations on the Australian coast, with no hydrocarbons detected. This sampling 

data is of extremely limited utility because of the very small sample size. The DEWHA 

submission admits that “more timely provision of better quality information would have 

been beneficial in terms of assessing potential impacts on coral and fish spawning events 

that were occurring in the general vicinity of the Montara well.” 

While it is unclear why water quality sampling was so delayed and limited, and why so 

many of the samples were contaminated, it does seem clear from the DEWHA Submission 

that there was some disagreement between DEWHA and other response authorities 

regarding the importance of water quality monitoring. The Submission states, “DEWHA 

requested on numerous occasions that water quality monitoring, to assess the vertical 

and horizontal distribution of oil and oil/dispersant mixes, be undertaken. These requests 

were actioned in late September 2009 and results were received in early November 

2009.” The cause for these delays and shortcomings bear further consideration. 

Independent sampling conducted by a local Senator (detailed in a Submission) identified 

dissolved hydrocarbons consistent with the gas chromatography “fingerprint” for Montara 

oil as far away as 112 km from the well location. Satellite imagery taken over the course 

of the release shows a significant plume from the spill, and a considerable spill area. This 

information suggests that additional whole water sampling from other locations might 

have provided more information about how quickly the oil was dispersing, and whether 

there were any areas where TPH concentrations posed a specific threat to local wildlife or 

sensitive areas. 

 

8

 http://www.dec.state.ak.us/SPAR/PERP/RESPONSE/SUM_FY05/041207201/041207201_flt_index.htm 

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Shoreline Assessment Ground Surveys 

The Environmental Monitoring Plan envisioned that surveys would be conducted to assess 

impacted shorelines or shorelines at risk, in order to characterize their “sensitivity and 

amenability to cleanup operations.” According to the DEWHA submission, shoreline 

assessment surveys have been conducted at Hibernia Reef and Ashmore and Cartier 

Reserves, with results not yet received beyond the reporting of visual observations. Postimpact surveys are supposed to continue at Browse and Cartier Islands and at Ashmore 

Reef in early 2010. 

A shoreline assessment study took place from 20 to 25 October (2 months after the 

uncontrolled release began), and sampled sediments on the islands of Ashmore Reef, 

Cartier Islet and Hibernia Reef. No oil was observed on the shorelines at that time. 

However observations made from the boat included many observations of oil sheens, 

some very near the reefs being studied, observations of dispersant as a white gloss of or 

white globs on the water, and observations of animals near or within the oily areas. 

Monitoring of Dispersant Efficiency and Fate of Dispersed Oil 

The DEWHA submission notes that this study, which was conceived as a separate 

endeavor under the original Environmental Monitoring Plan, was merged with the 

Monitoring of Oil Character and Fate Effects study. As discussed above, this study has 

yielded virtually no relevant information that could be used to assess the efficiency of 

dispersant applications nor the fate of dispersed oil. 

A plan was in place early on to study the effectiveness of dispersants through 

fluorometry. However, the correlation between TPH and field fluorometry readings was 

poor, which is a common problem with fluorometry.9

 Visual cues were used instead to 

determine dispersant effectiveness, and to track the movement of oil. A quote from 

DEWHA's submission states "The water quality monitoring undertaken was of limited 

assistance to DEWHA in determining the horizontal and vertical distribution of oil and oil 

dispersant mixes because of the limited number of useable (i.e. not contaminated) 

samples collected. In particular, only four dispersant operations were monitored for oildispersant mix distribution and of those operations, three different dispersants were 

applied. More timely provision of better quality information would have been beneficial in 

terms of assessing potential impacts on coral and fish spawning events that were 

occurring in the general vicinity of the Montara well." 

As a result, although the Monitoring Plan called for detailed plume modeling of the 

dispersed oil, no such plumes were ever charted because the information was not 

collected. More detailed monitoring and reporting of the concentration and location of oil 

in the water could have helped determine the impact of dispersant use, and the potential 

impacts of the dispersed oil on the Timor Sea ecosystem. 

Perhaps the most significant gap in the dispersant monitoring was a lack of consideration 

for the potential toxicity impacts of the intense dispersant application. Chemically 

 

9

 Flurometry provides a general measurement of the presence of substances that fluroesce, which includes oil, 

chemically dispersed oil, and a number of naturally occurring substances. It is extremely difficult to calibrate a 

fluorometer so that it provides quantitative measures. 

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dispersed oil has been demonstrated to be more toxic to some marine organisms than 

untreated oil. Researchers have also found that the undispersed oil residue that is left 

behind following a dispersant application may be more toxic than the untreated oil. The 

toxicity of chemically dispersed oil may be enhanced by exposure to sunlight, and 

chemical dispersion of oil has been shown to enhance oil uptake and bioaccumulation. 

Direct exposure to misapplied dispersant can also harm birds and mammals. None of the 

monitoring or sampling conducted to date has addressed any of these possibilities. 

Wildlife Impact Monitoring 

No wildlife response began until August 27, after a report of an oiled bird was received. 

DEWHA states they did not initiate wildlife response earlier than that because it was not 

within their authority. This was extremely reactive and not typical of best practices; 

usually, wildlife response is initiated immediately, before impacted animals are reported. 

The first noted survey of environmental impacts was the rapid aerial survey of "mega 

fauna," defined as cetaceans, birds and marine reptiles (turtles and sea snakes) 

commissioned by DEWHA on 24 September 2009 - nearly five weeks after the spill began. 

Daily inspections of Ashmore Reef and its surrounds were conducted by Wildlife Response 

and Customs Officers. These inspections found 29 oil affected birds (19 deceased), and 

at least 2 oil affected sea snakes (deceased). Hydrocarbons from the Montara spill were 

observed on Ashmore Reef and Browse island shorelines. Biodiversity studies conducted 

by WWF Australia during roughly the same timeframe as the DEWHA surveys found 

widespread surface slicks, many in the vicinity of vulnerable wildlife populations. The fact 

that documented wildlife impacts appear low could be due to a lack of diligence in 

monitoring and sampling. 

Aerial monitoring was the primary method for assessing megafauna impacts. The Inquiry 

should consider whether this method provided ample visibility to monitor potentially 

impacted species, based on the flight elevation and speed, and the records of observers 

(photographs, etc.). Is it possible that another methodology would have provided a more 

accurate view? 

On 4 September, four fish of four different species were landed by a commercial 

fisherman and later analyzed for hydrocarbons. The report does not indicate the exact 

location where these fish were caught, or what prompted the analysis of these particular 

fish. It does not appear that the analysis was part of any monitoring plan, although the 

Scientific Monitoring Plan does indicate that additional fish samples would be taken. No 

other fish were sampled during the operational studies. These fish were frozen before 

analysis, preventing any analysis of their bile, which would have been a much more 

sensitive indicator of hydrocarbon impact. A program designed to capture and analyze 

bile from fish in a number of different locations around the spill as the release was 

occurring would have provided a much better indication of the spill's immediate impacts 

to fish stocks. 

Overall, wildlife impact monitoring appears to have been rather cursory. Considering that 

this information was considered in assessing the “triggers” for long-term megafauna 

surveys, the Inquiry should consider whether the lack of documented impacts reflects a 

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lack of diligence in carrying out monitoring. 

Scientific Monitoring Programs 

According to the DEWHA Submission, the scientific monitoring programs identified in the 

Environmental Monitoring Plan are to be implemented based on certain “triggers” that are 

related to potential impacts to vulnerable species as identified in the EPBC Act Policy. Of 

the seven scientific monitoring programs proposed, five have been initiated, two have not 

been triggered. 

The Environmental Monitoring Plan indicates that there was some level of peer review in 

the evaluation of the Scientific Monitoring Programs. The Inquiry should review those 

evaluations to help determine whether the long-term monitoring studies incorporate the 

peer review recommendations and comments. The Submission from the University of 

West Australia raises some serious concerns about the quality of the science proposed 

and conducted. 

Marine Megafauna Aerial Assessment Surveys 

These surveys are designed to assess any disturbance or harm to megafauna in the open 

sea. Marine megafauna aerial assessment surveys have not been initiated. 

According to the Environmental Monitoring Plan, the trigger for these surveys was to be 

“harm or elevated risk or concern” to marine megafauna. It is interesting that this trigger 

was not activated, given the results of the WWF Australia biodiversity survey and even 

the DEWHA surveys. It is impossible to find impacts if you are not really looking for 

them. The EPBC Act Policy Statement (Attachment A to DEWHA Submission) repeatedly 

cites the Precautionary Principle as underlying the agency’s policy. Yet, the opposite 

standard appears to have been applied in this case. The reliance on triggers to 

implement monitoring completely contradicts the precautionary principle, which would 

presume that there have been impacts and set out to try to gather as much information 

as possible on those impacts, rather than forestall monitoring based on extremely limited 

data. Perhaps if the operational monitoring had been more diligent, the triggers for longterm megafauna assessment would have been realized.

Shoreline Ecological Assessment Aerial Surveys 

These studies are designed to assess any disturbance of harm to shoreline habitats 

including ecological character of the mainland shorelines and associated islands, Ashmore 

Reef and other reefs, Ramsar wetlands or other coastal areas that may be disturbed by oil 

discharge. According to the DEWHA Submission, this study has been triggered for a 

baseline survey of the Kimberley Coast between Darwin and Broome. The field work for 

this survey was conducted between 8 and 18 November 2009 and the report is expected 

in early 2010 (no report published as of 26 February 2010). Further activation of this 

study will depend on the results of operational monitoring study one. 

Assessment of Fish Catch for Presence of Oil 

These studies are designed to determine whether commercial fish have acquired a taint 

or other undesirable characteristics through contact with the spilt oil. The proposal for this 

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study was approved on 10 December 2009. Field work is expected to be conducted in 

January 2010, following postponement due to weather conditions in the region during 

December 2009. No further information on this study (including a methodology) is 

available. It is unclear what type of sampling will be conducted nor the level of analysis. 

The collection of live vs. frozen samples would facilitate a more meaningful level of 

analysis. 

Assessment of Effects on Timor Sea Fish and Fisheries 

This study is designed to assess any effects on fish species (all life stages) of impacted 

waters. This study has been triggered for during and post response assessments. Field 

work for assessments during the response was conducted between 6 and 19 November 

and the report is expected in early 2010 (no report available as of 26 February 2010). 

No information is available regarding the methods to be used to assess the impacts to 

fish species, but in order to truly assess these impacts, long term studies are required. Oil 

has a more severe impact on embryonic and larval stages of fish than it has on adult 

individuals. In order to reveal the impacts to the fishery, young fish must be studied, and 

the study must be continued long enough to allow impacted larvae to grow into marketsize adults. There has been some research done on hydrocarbon exposure to herring 

embryos which shows that even low levels of polycyclic aromatic hydrocarbon (PAH) 

exposure in embryonic fish can cause severe developmental problems.10

 

Offshore Banks Assessment Survey 

This study is to determine whether there has been any impact of, or effect on, the marine 

banks in the region. Offshore banks assessment surveys have not been initiated. 

According to the Environmental Monitoring Plan, the trigger for these surveys was to be 

“harm or elevated risk or concern” to offshore banks. 

The Inquiry should evaluate the determination that the offshore banks were not at any 

elevated risk for harm, particularly given the widespread application of dispersants and 

the potential for dispersants or dispersed oil to impact these areas. 

Shoreline Ecological Ground Surveys 

This study is designed to quantify any effects on coastal fauna or flora. As a priority, the 

study will look at resources and areas identified as sensitive. DEWHA expected to receive 

proposals for the implementation of these studies in December 2009. There is no further 

information available about these studies. 

Oil Fate and Effects Assessment 

This study is meant to build on the Operational Oil Character Fate and Effects study by 

investigating the distribution, weathering fates and effects of residual (post response) oil 

at sea. It encompasses an assessment of untreated oil and dispersant treated oil and oil 

in waters and sediments, to include trajectory and exposure assessments, analysis of 

sediment plume modeling, dispersant application and fate modeling, and water and biota 

 

10 The following link contains videos comparing the embryonic development of healthy herring embryos with 

those exposed to low levels of PAHs. http://www.research4d.org/projects/herring/herring.html 

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sampling. According to DEWHA, as of 22 December 2009, proposals were being 

reviewed. 

It is important that the Fate and Effects Assessment addresses some of the discrepancies 

between spill documentation of the total footprint of the spill and information presented 

through other media, such as the Skytruth satellite imagery. The images at the link 

http://www.flickr.com/photos/skytruth/sets/72157622226354812/detail/ and the image 

at http://blog.skytruth.org/2010/02/timor-sea-drilling-spill-cumulative.html show an 

estimate of the extent of cumulative slicks from the blowout (with US State of Virginia 

shown for scale). According to this image, the spill footprint covered more than 57,000 

km2

. This is a much greater area than is described in the spill documentation, and bears 

further research. 

Conclusions and Recommendations on TOR 7 

• The Environmental Monitoring Plan that establishes both the Operational 

and Scientific Monitoring Studies was developed through negotiation 

between PTTEPA and DEWHA. It is unclear the level to which this process 

may have compromised the scientific diligence of the monitoring studies. 

Overall, the Operational monitoring conducted to date and the Scientific 

Monitoring proposed is weak and vague. The Submission by the University 

of Western Australia points to potential conflicts of interest among the 

consultants hired for much of the monitoring and sampling work.

• There appears to have been a significant lack of transparency in the design, 

implementation, and data reporting for many environmental monitoring 

activities. The DEWHA website contains only superficial information and 

initial reports from Operational Modeling. Methodologies for the Scientific 

Monitoring studies do not appear to be within the public domain. 

• The fact that environmental monitoring was delayed and in many cases, 

superficial, results in a loss of valuable information that is needed to may 

fully understand the extent of the spill’s impacts. Absent this knowledge, it 

is nearly impossible to effectively remediate those impacts and restored 

injured species, habitats, and ecosystems. 

• There appears to have been a lack of baseline data for the spill region. 

Baseline studies should be conducted in all areas of oil and gas 

development. 

• Given the heavy application of dispersants over a long duration, the lack of 

water quality sampling seems particularly negligent. The AMSA Submission 

states that "no significant impact would be expected to species within the 

upper 5 metres of the water column given predicted levels of dispersed oil 

(30-50ppm). This compares with a regulated discharge level of 30ppm for 

produced water formations from facilities." However, no further analysis 

was done to verify that levels of dispersed oil stayed within these 

parameters. There does not appear to have been any rigorous sampling 

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below the dispersed slick for the purpose of quantifying the levels of 

dispersed oil, to ensure that they did not exceed the expected range. 

• Information and data on spill trajectory and delineation was poorly 

captured and communicated. It is extremely difficult to find any plume or 

slick diagrams within the official incident documentation. 

• Water quality sampling was extremely limited and conducted over a short 

duration, after a significant delay. 

• Wildlife response activities appear to have been delayed, and wildlife 

impact surveys were not initiated until over a month after the spill was 

initiated. The scientific monitoring program indicates that no further 

megafauna or offshore bank assessments will occur because of a lack of 

triggers. 

• Fisheries sampling methodologies and results have not been 

communicated. It is unclear whether the sampling has been initiated, what 

type of sampling will be conducted nor the level of analysis. The collection 

of live vs. frozen samples would facilitate a more meaningful level of 

analysis. It is also important that fisheries sampling continue long enough 

to assess any potential impacts to larval or embryonic fish. 

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