STOS 2017: Relevant Issues not Disclosed in Expert Reports for - - PowerPoint PPT Presentation

STOS 2017: Relevant Issues not Disclosed in Expert Reports for Shell Taranaki

Clark Thomborson

1971-5: BS(Hon.) Chemistry, Stanford University 1973-5: Ass’y Language Programmer for FT-NMR spectrometers, Nicollet Instruments 1996- : residence in New Zealand 2012- : citizen of New Zealand

Contaminants in Aqueous Solution

• To date, no expert evidence provided to the DMC has discussed the

bio-available contaminants in aqueous solution, at dangerous concentrations, which will be released by the proposed activity.

• Polycyclic aromatic hydrocarbons (PAHs) are dangerous to biota, in part,

because they are very slightly soluble in water.

• The PAH content of any crude-oil slick will dissolve. Contrary to the

assumptions made by Sharon De Luca when preparing her report, the dangerous effects of an oil slick are not limited to biota which come into direct contact with the slick. (Ref: Brussaard et al, in Nature Comms, 10.1038/ncomms11206, 2015)

• Some of the PAH content of any dispersed sediment will dissolve, and will be

bioaccumulated in nearby biota.

Chronic vs Acute Toxicity

• To date, no expert evidence provided to the DMC has discussed the

chronic effects of sub-lethal exposure to ecotoxins, such as PAHs.

• Cumulative effects may increase to dangerous levels, if sublethal

concentrations of PAHs are released over an extended period of time.

• Evaluation of this risk will require careful modelling – we should not just

ignore the possibility, even though the Shell Taranaki experts to date have not addressed it.

• No bio-accumulation data has been provided. (Has Shell Taranaki not been

monitoring PAH content in shellfish or phytoplankton near MPA and MPB, or are they not disclosing the results of their monitoring?)

Rate of Ecotoxin Accumulation

• To date, no expert evidence provided to the DMC has discussed the

rate at which PAHs and other ecotoxins will accumulate in non-mobile biota and benthic sediments, as a result of the proposed activity.

• “TPH levels in the sample from the S250 station reached 210 mg/kg, which

was an increase from the levels detected at this station in 2015 (119 mg/kg), but was still below the ecological protection trigger value for TPH (275 mg/kg - as set out in Simpson et al., 2015) which indicate the level where negative ecological effects might occur.” Source: MPA Benthic Survey Report, 2016, p. 38.

Current Science or ISQG?

• To date, no expert evidence provided to the DMC has discussed any

risk-assessment measure more recent than the ISQG.

• The 2000 ISQG are based on the scientific findings that were summarised in a

survey article by Long et al. in 1995.

• Is it permissible for any expert witness in this hearing to ignore any directly

relevant and widely disseminated scientific finding published after 1995, when making their risk assessment?

• Is it permissible for any expert witness in this hearing to ignore the directly-

relevant TPH risk-assessment metric used in the Benthic Survey report for 2016?

• In my current professional capacity, I lecture on risk assessments for

computer systems to postgraduates.

• Generally: if two risk assessment methodologies produce significantly different results

for an important asset at risk, in my field of expertise it would be prudent to assess the cost-benefit of deploying a third methodology.

Locations of Contaminated Sediment

• To date, no expert evidence provided to the DMC has disclosed any

reason to be confident that the proposed relocations of sediment will not occur in highly-contaminated locations.

• There must be cutting piles in the vicinity of MPA and MPB.
• There is evidence of hydrocarbon leakage from prior activity at MPA, as

discussed in the Benthic Survey report 2016.

• Should there be a consent condition on the placement of jack-up rigs, to

lessen the probability that a highly-contaminated sediment will be disturbed – and its contaminants released into aqueous solution?

Acenapthylene and Acenapthene

• These are commonly occurring PAHs in crude oil.
• There was an unfortunate typo in the Benthic Survey tables, providing

concentrations for “acenapthlene”. From context, and from accurate spelling elsewhere in the report, I am now confident it is

• acenapthene (but not acenapthylene) has been detected at elevated

concentrations in several locations near MPA in 2015 and 2016.

• Sharon De Luca did not consider it relevant to discuss the multiple

detections of acenapthene at biologically significant levels near MPA in 2015.

Expertise in completion products and muds?

• “Given the high proportion of low risk substances available (based on the

OCNS List), it is reasonable to assume that in most cases Shell Taranaki will be able to implement the approach to minimise the use of high-risk chemicals.” Will any of the low-risk mudding and completion products be economic, effective, and safe ways for Shell Taranaki to perform the proposed activities?

Any expertise in petrochemical selection?

• “Given the high proportion of low risk substances available (based on the OCNS

List), it is reasonable to assume that in most cases Shell Taranaki will be able to implement the approach to minimise the use of high-risk chemicals.” (Expert for Shell Taranaki)

• I believe it would be possible for an independent expert to estimate the average

number of high-risk non-CHARMABLE chemicals, and their volumes, which will be

• n the proposed jack-up rig during the proposed activities whenever a well is

being stimulated.

Sediment Grain Size

• I fail to understand why the small grain-size components of the

benthic sediments have not been characterised – instead they are lumped together as “silt and clay” – when these components will be highly relevant to estimates of dispersion of PAHs released by the proposed activities.

Jack-up Rig Fatigue? Solvency of Operator?

• Will you require an independent inspection of the structural integrity of

the jack-up rig, at least every five years?

• “A study to demonstrate life extension of an approximately 20 year old semi-

submersible rig for a further five years, without port inspection, is described.” [Pisarski et al., “Life Extension for a Semi-Submersible Drilling Rig”, in Life Extension Issues for Ageing Offshore Installations, DOI 10.1115/OMAE2008-57411, 2008]

• Will you require Shell Taranaki (or its successor) to post a bond or to

purchase insurance, so that if there is a major accident there will be sufficient funds for environmental remediation?

• Note: Hercules Offshore recently declared bankruptcy a second time, see

http://www.offshorepost.com/offshore-drill-crew-at-fault-for-catastrophic-blowout/ and http://money.cnn.com/2016/05/27/investing/hercules-going-bankrupt-again. “Hercules already reached a $196 million deal to sell a jack-up rig that operates in harsh environments to Maersk Highlander.”