UKOOA Drill Cuttings Initiative Issue 5 - Summer 2001

Welcome to the newsletter for the UKOOA Drill Cuttings Initiative. In this issue we bring you an update on the R&D programme Phase II, as well as news of the next Stakeholder Dialogue meeting which is scheduled for 20 November. By then, we will have had final reports for nine of the ten R&D tasks, as well as an interim report for the long-term disturbance modelling work (Task 4), which is due to be completed by the end of December.

Feedback from the stakeholder meeting is an important part of the process of our defining “best environmental practice” for dealing with cutting accumulations on the sea floor. The final assessment will be based on a comparative study of all the various options for managing the cuttings and to help in this process, a comparative assessment framework has been drawn up highlighting some of the issues that need to be considered in reaching a decision. We would welcome your views on this process. Further details may be found overleaf.

Finally, the independent Scientific Review Group has been busy evaluating research and reports as well as advising on scope and methodology. The Group’s chairman, Professor John Shepherd, director of the Earth System Modelling Initiative in Southampton, describes its most recent activities.

R&D UPDATE

Offshore trial

The cuttings lifting trials are now underway at BP’s North West Hutton platform in the northern North Sea and will last a total of ten days. State of the art environmental survey instruments have been installed both on the platform and at strategic points on the sea floor around the installation to record the performance of the lifting equipment and the dispersal of the plume. The cuttings are being reinjected into an abandoned well.

Peer Review

The independent Scientific Review Group (SRG) has now commented on three reports and is about to evaluate a further two. These are, respectively: the cuttings accumulations characterisation study by Rogaland Research (Task 1); AEA Technology’s feasibility study into the practicality of using an in-situ bio-reactor system as a technique for treating contaminants within accumulations (Task 5a); Dredging Research Ltd’s work with CEFAS on the option of covering the cuttings on the seabed (Task 5b); the toxicokinetics work by ERT (Scotland) on water based mud (WBM) deposits (Task 2a); Cordah’s assessment of the environmental impacts of representative oil based mud (OBM) and WBM cuttings piles (Task 2b).

In response to comments from the SRG, further testing for endocrine disrupters, as well as studies relating to the geotechnical and mineralogical properties of the accumulations are now planned. All comments will be incorporated into the final reports before being released on the initiative’s web site (www.oilandgas.org.uk/issues) in the autumn.

(See overleaf for further news from the SRG Chairman)

Water column and food chain effects

Tests conducted by URS-Dames and Moore (supported by TNO) to determine whether cuttings accumulations have any measurable impact on the food chain (Task 2c) were completed at the end of May, using chambers to simulate the conditions of OBM accumulations on the seabed. Analysis of contaminant levels in various biota introduced into the chambers, including lugworms, molluscs and bottom feeding fish, has begun.

Time series data

In Task 3, Rogaland–Research’s work with SINTEF seeks to determine the criteria that affect an accumulation’s characteristics over time. Scientists have completed the large-scale erosion studies and the results will be factored into the mathematical model BMT is building to predict changes in accumulation characteristics over time (Task 4). Experiments to establish the effects of bioturbation and recolonisation of piles by marine life are underway while the study into rates of natural degradation is also progressing, following adjustments to the experiment design, approved of by the SRG.

Long Term Fate Model

The timetable for BMT’s Long Term Fate mathematical model is dependent on the delivery of data from Task 3 and the lifting trials. However, the development phase should be completed and tested by late summer, with the final report due by the end of the year.

STAKEHOLDER DIALOGUE

A meeting will be held in London on Tuesday, 20 November 2001 to consult stakeholders on the findings of the initiative’s second phase of research and development. The session, together with feedback from the Scientific Review Group, will help to shape the Industry’s final recommendations for “best environmental practice” which will be presented by the DTI at the next meeting of OSPAR’s Oil Industry Committee in February 2002.

The Environment Council will again be managing the dialogue event on our behalf. Details will be sent out nearer the time.

ASSESSING BEP

A key aim of the UKOOA drill cuttings initiative is to provide information to stakeholders, including the general public, about the environmental consequences of a range of various management options for dealing with cuttings accumulations and the predicted ultimate fate of the cuttings material under those options. The options will be decided by comparative assessment, and will be undertaken for four characteristically different drill cuttings accumulations i.e., large and small, both with either oil or water based mud.

To help, the UKOOA steering group has prepared a comparative assessment framework which highlights a number of issues that need to be taken into account. These include environmental impacts at sea and on land, safety considerations, use of energy, impacts on amenities and communities as well as economic and legal factors. Results of comparative assessments will not be fixed, since technology advances as well as economic and social factors change.

The SRG will be invited to comment on the framework. If you would like to add your views, please contact the steering group chairman, Ian Silk, or Bob Hemmings on Tel. 01224 882000.

A REPORT FROM THE SRG

Professor John Shepherd, chairman of the Scientific Review Group (SRG) writes: The SRG (see Newsletter issues 1 and 2 for details) is continuing to provide a critical overview of the scientific aspects of the programme. It has reviewed and evaluated the proposals for the work being undertaken in Phase 2, and is reviewing the draft reports of the work as they are received. The SRG has also acted more pro-actively on several issues, providing advice to the programme managers and the sponsors on the future content and direction of the research programme. In particular, the SRG advised that much more emphasis should be given to the long term fate of the piles (and any material eroded from them), since this will be extremely important for the proper evaluation of any possible "leave in place" option. This initiative has led directly to a new task on the construction of a Long Term Fate Model to supplement the existing Short Term Fate Model. The SRG was able to suggest an outline of the structure of this model, and put the contractors (BMT) in contact with an expert on sedimentary diagenesis modeling to ensure that the work could be based on the latest and most efficient methodology in this field. The SRG has also advocated that continued serious consideration should be given to a possible Covering option, which was not originally considered to be a very promising approach. The work undertaken in Phase 2 on this has been reviewed, and the SRG considers that this is now likely to be among the short-listed options for the final evaluation, later this year.

UKOOA Drill Cuttings Web Pages

You will find full details of the R&D programme, the scientific review group and the stakeholder dialogue on the UKOOA Drill Cuttings web pages at www.oilandgas.org.uk.

Your contribution to the initiative is important and we value your comments and suggestions. Email Trisha O’Reilly at UKOOA on toreilly@ukooa.co.uk or call her on Tel. 020 7802 2422

20/07/01