An appraisal of underground gas storage technologies and incidents, for the development of risk ...

350 Pages·2008·6.88 MB·English

Health and Safety
Executive
An appraisal of underground gas storage
technologies and incidents, for the development
of risk assessment methodology
Prepared by the British Geological Survey
for the Health and Safety Executive 2008
RR605
Research Report
Health and Safety
Executive
An appraisal of underground gas storage
technologies and incidents, for the development
of risk assessment methodology
D J Evans
British Geological Survey
Kingsley Dunham Centre
Keyworth
Nottingham
NG12 5GG
with contribution from:
Dr J M West (Microbiology)
This report was commissioned by the Health and Safety Executive to help assess the safety issues associated with the
underground storage of natural gas. This has arisen because of the need to consider a number of applications submitted
by various operators in the UK who wish to develop such facilities. The rising numbers of applications are as a result of
UKCS oil and gas reserves showing rapid decline, to the extent that the UK became a net importer of gas during 2004.
The Government recognises that the UK faces an increasing dependency on imports, yet has very little gas storage
capacity and is, therefore, at a very real risk of supply shortfalls. It notes that the UK’s capacity to import, transport and
store gas and LNG efficiently has to be improved and this will require greater investment in new, timely and appropriately
sited gas (and LNG) supply infrastructure, part of which is likely to include (safe) onshore underground (natural) gas
storage (UGS) facilities.
This report and the work it describes were funded by the Health and Safety Executive (HSE). Its contents, including any
opinions and/or conclusions expressed, are those of the authors alone and do not necessarily reflect HSE policy.
HSE Books
© Crown copyright 2008
First published 2008
All rights reserved. No part of this publication may be

reproduced, stored in a retrieval system, or transmitted

in any form or by any means (electronic, mechanical,

photocopying, recording or otherwise) without the prior

written permission of the copyright owner.

Applications for reproduction should be made in writing to:

Licensing Division, Her Majesty’s Stationery Office,

St Clements House, 2-16 Colegate, Norwich NR3 1BQ

or by e-mail to [email protected]

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Foreword

This report is the product of a study by the British Geological Survey (BGS) into published or reported
problems with and incidents at underground fuel storage facilities. It forms part of a risk assessment of
underground gas storage in the UK for the Health and Safety Executive for which a contribution by
Quintessa is presented in a separate report (Watson et al., 2007).
For ease of use, the BGS report is presented in two volumes. Volume One comprises the text and
appendices. Volume Two contains the figures and tables referred to in Volume One.
The report and results contained are subject to either NERC General Conditions of Contract or, if
appropriate, conditions previously agreed between NERC and the customer. All such agreements include
intellectual property rights (IPR) considerations, including appropriate digital data and copyright
licensing fees.
Disclaimer: this is wholly independent and impartial review and appraisal of the technology of
Underground Fuel Storage (UFS), the incidents or problems encountered at various facilities and the
general geological conditions of those areas, with an overview of the potential or likely areas for
underground gas storage (UGS) in the UK, outlining the form that this might take. The BGS report
neither promotes nor supports UFS, one particular form of UGS or any proposed facility location.
Additionally, it does NOT address the control or prevention of pollution, safety of the surface or
subsurface infrastructure: the assumption here being that the design, maintenance and operation of such
facilities would be subject to the various HSE, waste and environmental regulations covered by such
documents as the COSHH (2002), COMAH (1999) and appropriate British Standards. For specific
elements of an underground gas storage facility, e.g. wells and surface installations, and operational
procedures, it is assumed that UGS applications would be subject to existing BS standards and legislation
for oil and gas exploration and should be applied or referred to in the first instance.
The parallel legislation includes:
• The Health and Safety at Work etc. Act 1974
• The Borehole Sites and Operations Regulations 1995
• The Dangerous Substances and Explosive Atmospheres Regulations 2002
• The Control of Major Accident Hazards Regulations 1999
• The Construction (Design and Management) Regulations 1994 (as amended)
• The Pipelines Safety Regulations 1996
• The Pressure Systems Safety Regulations 2000
These are in addition to the controls imposed under the Planning (Hazardous Substances) Act 1990 and
the Planning (Hazardous Substances) Regulations 1992.
Whilst the BGS has made every effort to provide the HSE with a programme of work and report designed
to meet their needs, this study is part of work in progress. BGS cannot be held responsible for: (i) any
measurements, tests or other activities that have not been included in the work and any resulting report
that subsequently become important at a later date; or (ii) any use which may be made of any part of this
work in progress, nor any reliance placed on any part of this work in progress, nor any advice or
information given in connection with this work in progress.
The British Geological Survey (BGS) has no responsibility for the persistence or accuracy of URL’s for
external or third-party internet websites referred to in this publication, and does not guarantee that any
content on such websites is, or will remain, accurate or appropriate. However, hardcopies of the
documents referenced have generally been made by the report writer(s) and could be obtained by writing
to them.
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iv
Acknowledgements

Many individuals have provided discussion during the project and to whom the author is
grateful. This assistance has been received at all stages of the study and their input or granting of
permission to reproduce data/images in order to illustrate this report is acknowledged below. Dr
Nigel Riley of the HSE is thanked for his detailed review of an early version of the draft report,
comments on which greatly improved the final product. Ron Demaine is thanked for the final
preparation of many of the diagrams contained in the report. The author would like to thank the
following for support and advice during the work:
Drs N Riley and S Welsh of the Health and Safety Executive
Drs S Turner and D Keeley of the Health and Safety Laboratories
Mr E Hough, Drs GA Kirby, S Holloway, R Cuss, AH Cooper & NJ Riley and Professor M
Culshaw (BGS)
Drs S Watson and R Metcalfe (Quintessa)
Jennifer Cunningham, BGS Wallingford (Figure 15 - major aquifers cropping out in England and
Wales)
G Church and R Smith (BGS, IPR section)
Kate Sanderson (SABIC UK Petrochemicals) for information relating to the Teesside brine
caverns and their usage
Richard Stevenson (INEOS) for information relating to operations in the Cheshire saltfield
Schlumberger for permission to reproduce Figure 3
David Lee Photography Ltd, Barton upon Humber for permission to reproduce the photograph in
Figure 8
The Geological Society, London for permission to reproduce both the line drawing and
photograph in Figure 8 and the image of salt core in Figure 10b (From Smith, D.B. 1997;
deceased, July 2007)
NATIONAL TRANSPORTATION SAFETY BOARD (NTSB) for permission to reproduce the images of
the Carlsbad pipeline and Brenham incidents in Figure 25
California History Room, California State Library, Sacramento, California for permission to
reproduce the image in Figure 23a (www.library.ca.gov/calhist/index.html).
Lena Tabilio and the California Division of Oil, Gas and Geothermal Resources for permission
to reproduce the image in Figure 23c (http://www.consrv.ca.gov/index/siteMap.htm#doggr)
Springer Verlag for permission to reproduce Figure 28 (from Scherer et al., 2005, Environmental
Geology)
Kansas Geological Survey for permission to reproduce images and figures from their website
relating to the Hutchinson incident, 2001 (Figures 5c&d, 25 and 35)
Chief Forbes and the Hutchinson Fire Department for permission to reproduce photographs of
the scenes in Hutchinson town immediately following the January 2001 gas storage incident
(Figures 25 and 35)
Mike Heideman and the Kansas Department of Health and Environment (KDHE) for permission
to reproduce the photograph of the S-1 well site at the Hutchinson gas storage facility (Figure
35)
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CUDD Drilling and Shannon Pope of RPC Inc are thanked for permission to reproduce images
in Figures 25 and 35
DS and MJ Jackson for permission to reproduce photographs relating to salt brining activities at
Preesall, Lancashire (Figure 5a&b)
Jeanette Vosberg, Save Ballona Wetlands for permission to reproduce the image of gas bubbling
up along old well (Figures 22d and 44c)
Hertfordshire County Council and the Chiltern Air Support unit for permission to reproduce
images of the Buncefield accident (Figure 27)
Star Energy for permission to reproduce images of the Humbly Grove gas storage facility
(Figure 29)
E. Schweizerbart Science Publishers for permission to reproduce the photographs of the
Teutschental incident (Figure 30)
This product includes mapping data licenced from Ordnance Survey with permission of the
Controller of Her Majesty’s Stationery Office © Crown Copyright and/or database right 2007.
All rights reserved. 100037272
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Contents
1 Introduction ....................................................................................................................... 1

1.1 Background ................................................................................................................ 1

1.2 Risk analysis and risk assessment of UGS .................................................................. 2

1.3 Structure of the report................................................................................................. 3

2 The various types and numbers of Underground Fuel Storage facilities and stored

products .................................................................................................................................... 6

2.1 Hydrocarbon Products ................................................................................................ 6

2.2 The basic concepts and storage scenarios.................................................................... 6

2.2.1 Basic concepts, ‘working’ and ‘cushion’ gases ........................................................ 7

2.2.1.1 Composition of cushion gases and ‘blanket’ materials ...................................... 8

2.2.2 Permeabilities and capillary entry pressures of well cement, shale and salt .............. 9

2.2.3 The process of drilling an exploration well/injection well, well completions and

casing .............................................................................................................................. 10

2.2.4 Damage to gas storage wells and reservoir formations........................................... 12

2.2.5 Depleted oil/gasfields ............................................................................................ 13

2.2.5.1 BS EN 1918-2:1998........................................................................................ 13

2.2.5.2 Background .................................................................................................... 13

2.2.5.3 Drive mechanisms and depleted reservoirs...................................................... 13

2.2.5.4 The Process of Gas Storage............................................................................. 14

2.2.5.5 Presence and effects of hydrogen sulphide (H S) in oilfields........................... 14

2
2.2.5.5.1 Effects of H S ............................................................................................ 15

2
2.2.5.5.2 Incident at Gasfield, Chongquing, China .................................................... 16

2.2.5.5.3 In the UK context ....................................................................................... 16

2.2.5.6 Susidence associated with oil and gas production............................................ 17

2.2.6 Aquifers ................................................................................................................ 17

2.2.6.1 BS EN 1918-1:1998........................................................................................ 17

2.2.6.2 Background .................................................................................................... 17

2.2.7 Salt caverns........................................................................................................... 18

2.2.7.1 BS EN 1918-3:1998........................................................................................ 20

2.2.7.2 Background .................................................................................................... 21

2.2.7.3 The process..................................................................................................... 22

2.2.7.3.1 Well design, spacing, cavern design and shaping........................................ 22

2.2.7.3.1.1 Example of a proposed salt cavern gas storage well casing program at

Preesall, NW England .............................................................................................. 23

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2.2.7.3.2 Salt cavern design and construction............................................................ 23

2.2.7.3.2.1 Cavern stability and damage -minimum and maximum cavern operating

pressures ............................................................................................................. 24

2.2.7.3.2.2 Leaching rates and brine disposal ......................................................... 26

2.2.7.3.3 Subsidence occurring with cavern formation and overburden/caprock

stability ................................................................................................................... 26

2.2.7.3.4 Insoluble (non salt) interbeds......................................................................27

2.2.7.3.5 Summary and examples of proposed UK cavern design and operational

ranges ................................................................................................................... 27

2.2.7.4 Commissioning of caverns – pressure testing .................................................. 29

2.2.7.5 The stored products and cavern operation ....................................................... 29

2.2.7.6 Asymptotic pressurization of a cavern – post abandonment............................. 30

2.2.7.6.1 High pressure brine release, Preesall Brinefield, Fylde, Lancashire............. 31

2.2.8 Other underground fuel storage scenarios.............................................................. 31

2.2.8.1 Abandoned/reconditioned coalmines............................................................... 31

2.2.8.2 Abandoned salt mines ..................................................................................... 31

2.2.8.3 Abandoned limestone mines ........................................................................... 32

2.2.8.4 Rock Cavities other than salt and previous mine operations ............................ 32

2.2.8.4.1 Lined rock cavities (LRC) .......................................................................... 32

2.2.8.4.2 Unlined rock cavities.................................................................................. 32

2.2.8.4.3 UK Mined (Unlined) Cavern Storage – Killingholme, North Lincolnshire.. 33

2.2.9 LNG storage – potential future developments........................................................ 34

2.2.10 Examples of storage of different types of energy in salt caverns and other

geological environments .................................................................................................... 35

2.2.10.1 Hydrogen and Nitrogen storage ...................................................................... 35

2.2.10.1.1 Tees Valley Hydrogen Project and renewable energies ............................. 35

2.2.10.2 Compressed Air Energy Storage (CAES)........................................................ 36

2.2.10.2.1 Huntorf, Germany .................................................................................... 36

2.2.10.2.2 McIntosh, Alabama, USA......................................................................... 36

2.2.10.2.3 Norton, Ohio ............................................................................................ 37

2.2.10.2.4 Iowa stored energy plant........................................................................... 37

2.2.10.2.5 Markham, Texas.......................................................................................38

3 Hydrocarbon seeps in petroleum-bearing basins ........................................................... 39

3.1 Introduction.............................................................................................................. 39

3.2 UKCS oil and gas seeps............................................................................................ 40

3.3 Hydrocarbon Migration ............................................................................................ 42

3.4 Cap rocks, faults and seals........................................................................................ 42

3.5 Hydrocarbon leakages and flux rates ........................................................................ 45

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4 Salt deposits and factors relevant to developing gas storage caverns............................ 47

4.1 Introduction.............................................................................................................. 47

4.2 Salt creep.................................................................................................................. 47

4.2.1 Creep behaviour of halite (rocksalt) in the temperature range 20-200ºC and natural

strain rates.......................................................................................................................... 48

4.2.2 Original brine in salt deposits and its migration through and effects on the rheology

of salt bodies...................................................................................................................... 49

4.2.3 Salt glaciers, rainwater and deformation mechanisms ............................................ 50

4.3 Gases in salt formations............................................................................................ 50

4.3.1 Gas in UK salt deposits ......................................................................................... 51

4.4 Anomalous zones ..................................................................................................... 51

4.5 Presence of gypsum and/or anhydrite........................................................................ 52

4.5.1 Dissolution of gypsum .......................................................................................... 52

4.5.2 Gypsum/anhydrite transition ................................................................................. 53

4.6 Fractures of non-halite interbeds and infilling halite ................................................. 53

4.6.1 Infill of fractures by precipitation from brines ....................................................... 54

4.6.2 Non-brine infill origins (and fractures) .................................................................. 55

4.7 Wet Rockhead and subsidence in onshore UK saltfields ........................................... 55

4.7.1 Definition and origin of wet rockhead ................................................................... 55

4.7.2 Effects of brine exploitation on the features developed at wet rockhead................. 57

4.7.3 Subsidence associated with salt mining activities and unrelated to wet rockhead

conditions .......................................................................................................................... 58

5 Underground Gas Storage and areas most likely for development in Britain (including

Northern Ireland) ................................................................................................................... 59

5.1 Introduction.............................................................................................................. 59

5.2 Oil and gasfields....................................................................................................... 59

5.2.1 Midland Valley of Scotland................................................................................... 60

5.2.2 North West England.............................................................................................. 60

5.2.3 East Midlands Oil Province – Carboniferous play ................................................. 60

5.2.3.1 Enhanced Oil Recovery (EOR) operations in the East Midlands Oil Province . 61

5.2.3.2 Westphalian sandbody dimensions of the southern North Sea, eastern and

northern England ............................................................................................................ 61

5.2.4 Wessex-Channel (including the Weald) Basin ....................................................... 62

5.2.5 North East England (including the Cleveland Basin) ............................................. 62

5.3 Salt basins ................................................................................................................ 63

5.3.1 Non-halite interbeds in UK salt basins................................................................... 63

5.4 Aquifers ................................................................................................................... 64

5.5 Previous investigations into storing gas in porous strata in the UK onshore area ....... 64

5.5.1 Winchester Anticline............................................................................................. 65

5.5.2 Cliffe Anticline ..................................................................................................... 65

5.5.3 Napton .................................................................................................................. 65

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