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UKOOA DECOMMISSIONING COMMITTEE

DRILL CUTTINGS INITIATIVE

PHASE II RESEARCH & DEVELOPMENT PROGRAMME

UKOOA Decommissioning Committee Drill Cuttings Initiative - Phase II Programme

21st August 2000

CONTENTS

1. SUMMARY 1

2. INTRODUCTION 2

3. SUMMARY OF PHASE I 3

4. OUTLINE OF R&D PROGRAMME 4

5. REFERENCES 19


21st August 2000

1. SUMMARY This document represents an invitation to research and development groups to participate in the second phase of an investigation into the issue of legacy drill cuttings on the North Sea bed at the sites of multi well developments. The proposed work follows on from the laboratory- and desk-based exercises undertaken during Phase I. This work intends to fill the gaps identified in phase I that would allow sound scientifically-based recommendations for the destiny of cuttings accumulations at the end of a production development’s life. The primary objective of Phase II is, therefore, to collect sufficient data to enable a Best Environmental Practice (BEP) and Best Available Technology (BAT) to be determined for the present time, by method of comparative assessment.


5th May 2000 Page 2

2. INTRODUCTION Following completion of the UKOOA Phase I JIP on issues related to sea bed accumulations of drill cuttings, the Phase II programme has been developed to fill some of the major gaps identified. A summary of the Phase I findings follows in Section 3. The primary objective of Phase II is therefore to collect sufficient data to enable a Best Environmental Practice (BEP) and Best Available Technology (BAT), as defined by OSPAR, to be determined for the present time (Reference 1). In order to do this, the proposed work comprises both survey work, laboratory testing and offshore trials of lifting and possibly re-injection equipment. The major cost item of Phase II is the pilot lifting operation (Task 6). The specific objective of this activity is to understand the shortcomings of equipment and areas to be improved. In addition, Task 6 will also provide data to help understand the environmental impacts of the lifting operation, in the short term through survey, and in the longer term by use of the modelling tools.

The themes for Phase II are:

• Consistent sampling and surveying protocols;

• Toxic effects of cuttings as a whole as indicated by local biodiversity impact;

• Better understanding of natural degradation;

• Field trial of lifting – feasibility and environmental performance;

• Calibration of disturbance modelling; and

• Modelling of degradation, erosion and re-colonisation.


5th May 2000 Page 3

3. SUMMARY OF PHASE I Phase I of the project was undertaken between April 1999 and February 2000 and was essentially a desk top study to determine what data then existed on the content, effects and potential treatment and disposal methods. This work was successfully completed despite an aggressive schedule, and has identified a number of gaps in our knowledge of drill cuttings as well as providing pointers towards equipment that might be developed to lift, treat and dispose of cuttings.

The findings of Phase I are summarised as:-

• We have improved definition of the scale of cuttings piles, but there is still a paucity of data and inconsistent sampling techniques

• UKCS volumes are estimated at 700,000 m3 in the Central North Sea and 500,000 m3 in the Northern North Sea – both for multi-well installations only.

• Toxic effects are not known, but we have 30,000 mg/kg of Hydrocarbons in the cuttings (3%), compared with a NEC (No effect concentration) for mud shrimps of 10 mg/kg (10ppm).

• Heavy metals do not seem to be leaching or bio-available as long as the pile is not disturbed

• The top 5mm decomposes rapidly

• Opportunistic re-colonisation by Bristle worms occurs in 1 year

• The surface layer is continually changing due to erosion, consolidation, Bioturbation, sedimentation etc

• The bulk of a pile remains inert

• Disturbance mechanisms can be modelled.

• There is no proven remediation method

• Enhanced bio-remediation too theoretical as yet, but should be kept under review

• Covering is still a potential solution

• Re-injection is technically feasible but maybe operationally limited and of uncertain legal status

• Natural degradation still merits consideration

• Questions about secondary contamination and water volumes if recovery attempted

A summary report (Reference 2) has been prepared by DNV and both this and the full text of all the researchers reports is available at the UKOOA web site: www.ukooa.co.uk


5th May 2000 Page 4

4. OUTLINE OF R&D PROGRAMME The items to be studied in Phase II are derived from the results of the Phase I desk top exercise. The scopes of these items are described in more detail in the following pages. The table below summarises the items and gives a preliminary indication of the costs.

Task Title 1 Characterisation of cuttings piles 2a Toxicokinetics of WBM Drill Cuttings Contaminants in

Marine Sediment 2b Assessment of the Actual Present Environmental Impacts

of Representative OBM and WBM cuttings piles 2c Water Column and Food Chain Impacts 3 Initiate comparative time series data on factors determining future pile

volume from representative OBM&WBM cuttings piles. 4 Adaptation and evaluation of mathematical model 5a In-situ solutions: enhanced bio-remediation 5b In-situ solutions: covering 6 Pilot lifting operation 7 Evaluation of options for slurry handling; offshore, transport to shore and

onshore processing. 8 Comparative assessment: towards BEP/BAT options

The inter-relationship between the activities is shown on the figure.


5th May 2000 Page 5

PHASE II R&D PROGRAMMECHARACTERISTION & IMPACTS PROJECTS HANDLING/PROCESSING PROJECTS

3.Comparative time series data determiningfuture pile volume.

4.Modelling Adaption & Evaluation

5b.Covering

1.OBM/WBM RepresentativePile characteristics(OLF & Operators)

2.a. WMB Toxicokinetics effectsb. Impact assessment of present effectsc. Water column & food chain impacts

6.Offshore Lifting Trials Impacts

7.Slurry Handling; Offshore Transport;Onshore Processing

5a.Bioreactor & lab trials

8.Comparative Assessment (BEP/BAP)

1.1

1.2 2.1 2.2 2.3

6.1 6.3

7.1 7.2

3.1 3.2

4.1

5.1

1.2 2.1 2.2 2.3

Applicable Phase I R&D Project

9.1


5th May 2000 Page 6

Title Characterisation of cuttings piles Task 1

Objective Obtain more detailed data on the physical, chemical and biological composition of cuttings piles

Method Using OLF guideline protocols (including all geo-technical issues), carry out full characterisation of large WBM pile (Ekofisk) and large OBM pile (Beryl A). Obtain existing characterisation data from small WBM pile (Blenheim and Bladon) and small OBM pile (Maureen).

Timescale May - September, (for a limited number of different piles to be accurately characterised). Possible candidates (to be discussed with respective operators) may include NW Hutton, Maureen, Blenheim & Bladon, Brent Alpha, Linnhe, Hutton TLP plus Norwegian data i.e. Ekofisk & Frigg.

Inputs/outputs Phase 1 information / use OLF protocols to obtain requisite data from the range of pile types. Information acquired should be capable of being used by other Phase II research tasks in particular 2a, 2b, 2c, 3, 4, 5a, and 5b (including geo-technical issues identified as a gap in Phase 1 area 1.1 i.e. sheer strength and porosity); This information is necessary to form the basis for comparative assessments in determination of BEP.

Other issues • In addition to OLF characterisation, sediment samples should also be analysed for PCBs, endocrine disrupters (indicators) and anaerobic degradation (indicators).

• Co-ordination and communication of who is doing what & when, to avoid gaps and overlaps and management of new data. This would include liaison with UKOOA environment committee on sea bed survey data base.

• As part of Task 1 survey work, samples will be collected for Phase II R&D tasks 2a, 2c, 3, and 5b, as per requirements defined by lead contractor.


5th May 2000 Page 7

Title Toxicokinetics of WBM Drill Cuttings Contaminants in Marine Sediment

Task 2a

Contractor ERT (Scotland) Ltd

Objectives Determine the exposure/uptake/toxicity relationship for WBM cuttings-derived contaminants in sediments and those eluted into the water phase.

Method Identify WBM threshold levels for chronic and acute effects on sensitive test species (i.e. corophium volutator) including the use of the test protocols as followed in the variation work in Phase I research area 1.2

Timescale 6 months

Inputs/outputs Phase 1 knowledge, OLF protocol contaminants. Information acquired should be available for other Phase II research tasks (2c, 3, & 5a). Determination of contaminant significance, bio-availability, & chronic effect. Report should be useable in any comparative assessment.

Other issues • Closely integrate with Task 1 • OLF work on metals • Sample collection (from Ekofisk) will take place during Task 1 survey

(according to ERT’s instruction) and will be transported to ERT’s lab in Flotta.

Checklist of questions to be answered

1. Can contaminants other than oil be demonstrated as having no significant environmental impact?


5th May 2000 Page 8

Title Assessment of the Actual Present Environmental Impacts of Representative OBM and WBM cuttings piles

Task 2b

Contractor Cordah (with Akvaplan-Niva)

Objectives Develop an assessment of the environmental impacts of cuttings pile sets to provide the basis for a comparative assessment of management options

Method Using information obtained during Research Task 1, identify the extent of contamination for 4 base case piles (Ekofisk, Beryl A, Blenheim/Bladon, and Maureen) Once the extent of contamination for these 4 piles is estimated, summarise the environmental impacts on the whole of the North Sea. Convey these impacts in the context of other environmental issues within the North Sea, to enable stakeholders to understand the extent and significance of the drill cuttings impacts.

Timescale 6 months

Inputs/Outputs • Information from Cordah report from JIP Phase I (R&D Area 1.1) • Cuttings pile information from selected operators • OLF report (Guidelines for physical, chemical, and biological

characterisation of offshore drill cuttings piles) • Information obtained through other Phase II research areas • Dutch studies • Report should provide input the Phase II research task 8.

Other issues • Closely integrate with Task 1


1. What is the environmental impact of cuttings piles at present, compared with other environmental management problems faced by the North Sea?


5th May 2000 Page 9

Title Water Column and Food Chain Impacts Task 2c

Contractor URS Dames & Moore (with TNO)

Objectives Demonstrate (or not) the hypothesis that cuttings piles impacts are localised and limited to the sediment, with no effects on the water column (assuming no disturbance) or the food chain.

Method Determine the exposure/uptake/toxicity relationship for OBM cuttings-derived contaminants (inc. endocrine disrupters & NORM) eluted into the water phase are of low risk in the water column Develop trials (in–situ & lab based) to sample & analyse or expose indicator species (e.g. nephrops, & dab) to OBM sediments to determine any uptake into the food chain Sediment samples for this work will be collected from Beryl A during the Task 1 survey. Interface with Task 1 survey contractor (Rogaland) to define sample collection, storage, and transport requirements. Frozen/refrigerated samples of collected OBM pile material will be transported (via truck) from Stavanger to TNO’s lab in Den Helder, Netherlands

Timescale 6 months – 12 months

Inputs/outputs • Phase I knowledge • E&P Forum studies (1996) • OLF 3 year (1996/97/98) review of seabed surveys • Dutch studies • Information obtained through other Phase II research Tasks 1, 2a, 5a &

6 • Report should be useable in any comparative assessment

Other issues • Interface with OLF metals work to prevent duplication • Prevent Task 6 monitoring duplication


1. Can cuttings pile impact, if any, on the food chain be quantified?


5th May 2000 Page 10

Title

Initiate predictive time series data on factors determining future pile characteristics from representative OBM&WBM cuttings piles.

Task 3

Contractor Rogaland (with SINTEF)

Objective Initiate time series data on factors that determine future pile characteristics of cuttings pile sets.

Method Using all current knowledge including that from Tasks 1, 2, 3, 5 & 6, establish predictive time series data on microbial processes, re-colonisation, bio-degradation, settlement, erosion (including natural and operational disturbance) and sedimentation. Laboratory/ In-situ erosion experiments. Operators, in time, will take measurements to validate predictions.

Timescale 1year for predictive data analysis to meet JIP deliverables with contingency to cover gap analysis and one year for operator validation (improvements in data set will be an ongoing process beyond JIP)

Inputs/outputs • Phase I knowledge E&P Forum 1996 studies, information feed from Task 6 lifting trials

• Information acquired should be available for other research areas namely Tasks 1, 2, 4 & 5. Determination of rates of microbial processes, re-colonisation, bio-degradation erosion & sedimentation to allow evaluation of effect on range of pile types. Report, should be useable in the comparative assessment.

• Data necessary for predictive modelling

Other issues • Develop acceptable protocols (see OLF work) to ensure comparability of data from different piles

• Develop protocol for time series measurement, i.e. what samples/tests to repeat and how often

• Maximise data acquisition from Task 1 • Ensure data format is useable in modelling • Erosion rates could form part of modelling scope • Critical thickness for processes contributing to bio-degradation requires

definition. • Outer fringe where natural remediation works – implications for rate limiting

steps • Samples required for Task 3 experiments will be collected during Task 1

survey Checklist of questions to be answered

1. What is the rate of natural degradation in the surface layers of the cuttings piles?

2. What is the rate of erosion to the surface layers of the cuttings piles? 3. Does degradation influence the rate of erosion? 4. What is the rate of re-colonisation of the OBM contaminated sites? 5. What is the rate of sedimentation? 6. How would cuttings piles, if left to degrade naturally, be characterised in 50

and 200 years time? 7. Is there a difference between OBM and WBM with regard to natural

degradation? 8. What would be the appropriate monitoring programme for a natural

degradation ‘solution’? 9. How much would natural degradation cost (in terms of monitoring etc)? 10. What would be the energy consumption for natural degradation?



Title Adaptation and Evaluation of Mathematical Model Task 4

Contractor BMT

Objectives Incorporate and validate relevant activities and processes into existing mathematical model to allow prediction of redistribution of pile components following natural and operational disturbance events.

Method 1. Upgrade existing model to include effects from: • Erosion • Sedimentation • Compaction • Aerobic/anaerobic degradation • Bioturbation

2. Provide redistribution prediction following disturbance events, which should be compared with lifting trial results.

3. Calibrate the model according to lifting trial results. 4. Perform model runs on potential solutions (covering, leaving, in-situ

treatment, or lifting) for 4 base case piles (identified from Task 1).

Timescale 12 months

Inputs/outputs • Information obtained from Phase I • Information obtained from JIP Phase II R&D Programme Tasks 1, 3,

5a, 5b, and 6 • Improvement in scope and reliability of model to enable accurate

prediction of redistribution of pile components following natural and operational disturbance. Report information to be useable for comparative BEP/BAT analysis.

Other issues • Interface with lifting trials (i.e. data format)

• Test model prediction of lifting trials by comparison with actual results • Real data from current redistribution of cuttings material (Marine Lab

trial) • Influence of physical presence of installation not to be included • Define scope of work for long-term fate modelling


1. What is the environmental impact of trawling events over 10 and say 50 years?

2. What would be the impact of jacket removal? 3. How would cuttings piles, if left to degrade naturally, be characterised

in 50 and 200 years time? 4. How would cuttings pile site following retrieval be characterised in 50

and 200 years time?



Title In-situ Solutions: Enhanced Bio-remediation

Task 5a

Contractor AEA Technology

Objective To determine the upper boundaries of enhanced bio-remediation as a technique for degradation of pile contaminants and assess their potential environmental impact. Determine and compare with natural degradation, and consider the benefit added for the resources consumed.

Method Desk and lab-based feasibility study to determine cost, time & resource consumption and end point boundaries for a bio-reactor on a NW Hutton pile type (without jacket).

Timescale 3-4 months

Inputs/outputs Phase I knowledge, info from area (1) (2) (3)& (5), OLF “sandwich” experiment / Determination of upper boundaries on rates of enhanced bio-remediation mechanisms their impacts and comparison with natural degradation Report information acquired should be useable in the comparative assessments (determination of BEP) task 8.

Other issues • Interface with areas (1) (2)(3) &(5) • Toxicity of transition organics (partially oxidised aromatics) • Sufficient volume of sample recovered from offshore survey to allow lab

testing (this will control start time). It may be possible to start testing with existing samples (e.g. leftover samples from the Beryl survey)


1. What is the fastest possible rate of bio-remediation? 2. How long will each batch take to bio-remediate to a level of 100-10 mg/kg

(assume pile content is 300,000 mg/kg)? 3. How would you know when each batch was remediated? 4. What marine spread would be required to operate the sub-sea bio-reactor? 5. To what depth would bio-remediation be effected? 6. Could the bioreactor be deployed from a platform? 7. What would be the impact of jacket removal prior to remediation? 8. How would the bioreactor manage pile debris? 9. Could the platform footprint be bio-remediated with the platform in place? 10. How much would bio-remediation cost? 11. What would be the energy consumption be for bio-remediation? 12. Would the bioreactor work effectively for both OBMs and WBMs?



Title In-situ Solutions: Covering

Task 5b

Contractor Dredging Research Ltd

Objective To determine the limitations of relevant covering options on range of pile types for effectiveness against disturbance.

Method Desk study looking at the characteristics of the 4 base case pile types, to determine the following for each pile type: • Cap design, integrity for leach resistance trawlability • How the design would be implemented • Time, costs and resource consumption for implementation. • Study should consider the use of WBM cuttings for protection and shear

strength limitations as guidance for its suitability. • Evaluation of the impacts of pore water leaching from potentially compressed

cuttings pile

Timescale 6 months

Inputs/outputs Phase I knowledge, info from Phase II Tasks 1 and 3 Determination of limitations and impacts (including the leaching of pore space water) of covering techniques on range of pile types. Report information acquired should be useable in any comparative assessments (determination of BEP).

Other issues • Interface with Tasks 1 and 3 • Very long term stability – integrity warranty for suggested designs


1. What would be the minimal thickness for a cover? 2. What would the cover be constructed from? 3. What would be the maximum gradient over which a cover would be stable? 4. How would the cover be constructed? 5. How would you know it is working over the long term? 6. What kind of monitoring would be required? 7. What would be the impact of jacket removal prior to covering? 8. What would be the impact of trawling and storms to the cover? 9. How much would the covering cost? 10. What would be the energy consumption for covering?



Title Pilot Lifting Operation

Task 6

Contractor BP (with Halliburton and SWACO as main subcontractors) Objective 1. Verify and define removal systems and technology currently available.

2. Perform system test to confirm operability. 3. Implement an offshore test of equipment to determine the operating

parameters, feasibility and cost of (OBM) cuttings retrieval. 4. Understand the short and longer term environmental impacts of pile cuttings

disturbance. Method Using North West Hutton as a suitable location for the pilot programme the

following will be conducted (N. W. Hutton has been selected due to its availability and the expected timing of full decommissioning): • Engage contractor market to determine availability and costs of cuttings

removal systems • Develop equipment and conduct a “wet” trial of up to four systems and select

the two most efficient (and effective) for trial offshore. • Implement an offshore trial of max. two systems at N. W. Hutton to test

recovery efficiency of cuttings in and around jacket footings and debris. Obtain all necessary data and samples; this data would include operational data (volume and flow rates, density, etc.) and carrying out full characterisation of lifter material to support Task 7. 2x24 hour recovery duration trials are being targeted which will remove up to a maximum of 900m3 (plus recovered sea-water) of cuttings (Approx. 3.6% of the total).

• Dispose of the material generated in an environmentally responsible manner. (Base case is to re-inject the cuttings and all associated fluid).

• Implement a thorough environmental monitoring programme to assess the impacts of disturbance (An option could be to have the environmental monitoring listed as a separate item to separate the hardware issues from the environmental issues).

• Conduct a thorough evaluation of all results for application to full scale removal.

Timescale 9 months

Inputs/outputs Prior BP-A study on hardware potential (Note BP-A considered the ability to

safely execute such an offshore trial in summer 2000 as ‘go’/ ‘no go’ criteria for being included on the bid list. Phase I knowledge, info from Tasks 2 and 3 and comprehensive reporting requirements on: • Details of the current availability and effectiveness of cuttings lifting

equipment • Operating parameters obtained during the “wet” trial • Information on equipment performance offshore and comparison • Cuttings pile behaviour under removal conditions • Assessment of the environmental impact of disturbance (useable in any

comparative assessments) • Details of the disposal operation • Data for correlating plume (component) dispersion modelling • Accurate assessment of the technical and financial implications of complete

recovery • Removal at the edge of the pile, to ascertain ‘when to stop’ and how quickly

the seabed recovers



Other issues • Interface between JIP and BP-A as operator, particularly w.r.t. gateways for equipment selection and decisions to award, selection for offshore trial and readiness to go offshore

• If required, provide slurry/water samples for onshore treatment (Task 7) • Strong interfaces with Task 7 • Acceptability of data format for modelling (Task 4) • SRG input to monitoring programme • Other types and sizes of piles • Site restoration (possibly for scope of Tasks 2 or 3) • Marine Laboratory tests on single well site (May/June)


1. What is the typical rate at which cuttings can be removed from the sea-bed? 2. What is the range of composition of the slurry as it arrives at the surface? 3. What determines the ratio of solids to water and how can it be minimised? 4. What is the degree of secondary pollution (i.e. water column impact and area/

thickness of cuttings re-settlement) due to re-suspension caused by the dredge-head and the ROV/ crawler? What is the environmental impact of secondary pollution?

5. How much would removal to surface cost? 6. What is the energy consumption for removal? 7. What is the condition of the sea-bed under a cuttings pile? 8. How do you know when removing sea-bed rather than cuttings i.e. can you

see at dredge head or do you need to sample slurry at surface? 9. Can the rov/ crawler operate/ be controlled reliably within the jacket

footprint? 10. What are typical down-times for weather and system reliability (i.e. debris

blockages etc.)? 11. What is the best way to clear new debris as it is uncovered by pile removal? 12. Is it possible to remove a large 'conical' pile without major slumping, if so

how?



Title Evaluation of Options for Slurry (lifted pile material) Handling

Offshore, Transport to Shore, and Onshore Processing.

Task 7

Contractor ERM Objective Establish the implications and effects of handling large volumes of slurry

associated with lifting techniques at all stages from entrainment to final disposal both offshore or onshore. Establish the implications and effects of lifted pile material composition on all on-shore processing technologies

Method Use defined scenarios (as outlined below) to review the implications and effects arising as the result of lifting a cuttings pile similar to the one at NWHutton. Failure risk and environmental impact assessments should be carried out for each scenario. Assessments should identify cost, time, energy consumption, and environmental implications. Scenarios: • Re-inject slurry, re-inject cuttings • Treat slurry offshore and discharge, re-inject cuttings • Treat slurry offshore and discharge, ship cuttings back to the beach for

treatment and disposal • Ship slurry back to beach for treatment and discharge, ship cuttings back to

the beach for treatment and disposal The study will also include: • Supply data summary of characterised lifted material (from Task 6) to onshore

treatment technologies and assess the effect of sample composition on each technology

• Identification of slurry handling logistics requirements (including interfaces between the lifting techniques, fixed installation site, and offshore/onshore transport)

• Evaluation of vessel-based operations for offshore scenarios • Identification of slurry (& water discharge) issues relating quayside storage

and handling prior to treatment • Identification of potential slurry treatment technologies and sites

Timescale 9 months (to capture feed from Task 6)

Inputs/outputs Phase I knowledge, info from areas 6 & 7.1. Input from Phase II Task 6 for determination of issues and impacts of handling associated water at all possible stages in the process. This will include evaluation of vessel-based lifting operations, which could equally apply to multi-well sites not in the vicinity of a platform. Report information acquired should be useable in any comparative assessments (determination of BEP). Report information acquired should include: • Comprehensive information on process equipment performance and operating

parameters • Assessment of environmental impacts

Other issues • Interface with offshore lifting trial • Water removal techniques to be identified • Sample volume requirements • Validation of data output • Effects of scaling (increased volume) up




Relating to reinjecting slurry offshore ‘Need to Knows’ will predominantly be determined by the composition of the slurry as it arrives at the surface and the injection reservoir characteristics. 1. How much would reinjection cost? 2. What is the energy consumption for reinjection? 3. What legal issues would require addressing? Relating to reinjecting water offshore and shipping solids to shore 1. How would water be best separated from solids offshore? 2. How would solids be shipped back to shore e.g. skip and ship vs bulk loading

to dedicated vessel? 3. How much would reinjecting water and shipping solids cost? 4. What is the energy consumption for reinjecting water and shipping solids? 5. What legal issues, if any, would require addressing around the reinjection of

water? Relating to shipping slurry to shore, treating and disposing water 1. How would water be best separated from solids onshore? 2. How would the water be treated? 3. What are the discharge standards for the separated water? 4. How would slurry be shipped back to shore e.g. skip and ship vs bulk loading

to dedicated vessel? 5. How much would shipping slurry to shore, separating, treating and

discharging the water cost? 6. What is the energy consumption for shipping slurry to shore, separating,

treating and discharging the water? Relating to disposal of oily solids 1. Where, today, could the oily solids be land-filled? 2. Could a purpose built special waste land-fill facility be constructed? 3. What would be the long-term impact of the oily solids in the land-fill site? 4. How much would disposing of the oily solids cost? 5. What is the energy consumption for disposing of the oily solids? Relating to treatment and disposal of solids 1. What processes could treat the oily solids? 2. What existing plants could treat the oily solids? 3. Could a purpose built land-fill facility be constructed? 4. How is the oil disposed of? Can the oil be re-used? 5. What would be the long-term impact of the cleaned solids in the land-fill site? 6. How much would treating and disposing of the cleaned solids cost? 7. What are the throughput capacities of existing facilities (compared with the

volume to be treated)? 8. What is the energy consumption for treating and disposing of the cleaned

solids? Relating to treatment, disposal of oil and re-use of solids 1. What re-use opportunities are there for cleaned solids e.g. Scotoil cat litter

project? 2. What would be typical characteristics of the solid by-product? 3. What processes are required to realise these opportunities? 4. How much would re-use of the cleaned solids cost/ save? 5. What is the energy consumption for re-using the cleaned solids?



Title Comparative Assessment: Towards BEP/BAT Options Task 8

Contractor (on hold) Objective To determine, based on the results of Phase I and Phase II. the BEP/ BAT for

typical drill cuttings piles.

Method Provide specs for BEP/BAT inputs/outputs for the other tasks (quantitative and qualitative aspects such as cost, energy, & time) Collate data relating to in-situ, recover and re-inject and recover and ship to shore solutions. Review BEP/ BAT frameworks. Construct assessment for each of the above 3 potential solutions in terms for criteria suggested ‘for consideration’ under above frameworks. Conclude BEP/ BAT for a number of characteristically different piles. Review results (and sensitivities) to see if rule sets can be concluded (instead of case by case).

Timescale 8 months initially, but to be developed as technology develops and more data becomes available, particularly information relating to natural degradation.

Inputs/outputs • CTRs one to seven • Stakeholder value judgements • MADM theory • BEP/BAT determination / guidance for three main themes of in-situ; removal

to shore; remove to reinject. • SEBA paper

Other issues None



REFERENCES

1. OSPAR Convention 1992, Appendix 1

2 DnV Technical Report, Drill Cuttings JIP, Phase I summary report, Revision 2, 20th January 2000, Project 29003500



ATTACHMENT

OSPAR BEP/ BAT Definition



Ospar Convention

APPENDIX 1 - CRITERIA FOR THE DEFINITION OF PRACTICES AND TECHNIQUES MENTIONED IN PARAGRAPH 3(b)(i) OF ARTICLE 2 OF THE CONVENTION

BEST AVAILABLE TECHNIQUES

1. The use of the best available techniques shall emphasise the use of non-waste technology, if available.

2. The term "best available techniques" means the latest stage of development (state of the art) of processes, of facilities or of methods of operation which indicate the practical suitability of a particular measure for limiting discharges, emissions and waste. In determining whether a set of processes, facilities and methods of operation constitute the best available techniques in general or individual cases, special consideration shall be given to:

a. comparable processes, facilities or methods of operation which have recently been successfully tried out;

b. technological advances and changes in scientific knowledge and understanding;

c. the economic feasibility of such techniques;

d. time limits for installation in both new and existing plants;

e. the nature and volume of the discharges and emissions concerned.

3. It therefore follows that what is "best available techniques" for a particular process will change with time in the light of technological advances, economic and social factors, as well as changes in scientific knowledge and understanding.

4. If the reduction of discharges and emissions resulting from the use of best available techniques does not lead to environmentally acceptable results, additional measures have to be applied.

5. "Techniques" include both the technology used and the way in which the installation is designed, built, maintained, operated and dismantled.

BEST ENVIRONMENTAL PRACTICE

6. The term "best environmental practice" means the application of the most appropriate combination of environmental control measures and strategies. In making a selection for individual cases, at least the following graduated range of measures should be considered:

a. the provision of information and education to the public and to users about the environmental consequences of choice of particular activities and choice of products, their use and ultimate disposal;

b. the development and application of codes of good environmental practice which covers all aspect of the activity in the product's life;

c. the mandatory application of labels informing users of environmental risks related to a product, its use and ultimate disposal;



d. saving resources, including energy;

e. making collection and disposal systems available to the public;

f. avoiding the use of hazardous substances or products and the generation of hazardous waste;

g. recycling, recovery and re-use;

h. the application of economic instruments to activities, products or groups of products;

i. establishing a system of licensing, involving a range of restrictions or a ban.

7. In determining what combination of measures constitute best environmental practice, in general or individual cases, particular consideration should be given to:

a. the environmental hazard of the product and its production, use and ultimate disposal;

b. the substitution by less polluting activities or substances;

c. the scale of use;

d. the potential environmental benefit or penalty of substitute materials or activities;

e. advances and changes in scientific knowledge and understanding;

f. time limits for implementation;

g. social and economic implications.

8. It therefore follows that best environmental practice for a particular source will change with time in the light of technological advances, economic and social factors, as well as changes in scientific knowledge and understanding.

9. If the reduction of inputs resulting from the use of best environmental practice does not lead to environmentally acceptable results, additional measures have to be applied and best environmental practice redefined.

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