Environment Enterprise and Transportation Committee
27th August, 2009
Agenda Item No. 24
Appendix
MOSSMORRAN & BRAEFOOT BAY
INDEPENDENT
AIR QUALITY MONITORING REVIEW GROUP
2008 Annual Report
August 2009
CONTENTS
1.
INTRODUCTION
2.
OBSERVATIONS
3.
CONCLUSIONS
APPENDIX 1
The Review Group: Constitution and Terms of Reference
APPENDIX 2
Membership of the Review Group
APPENDIX 3
Regulatory and Policy changes relating to air quality in
2008
APPENDIX 4
Regulated emissions to air
APPENDIX 5
2008 flaring report
APPENDIX 6
Atmospheric Monitoring Study at ExxonMobil Fife
Ethylene Plant Mossmorran
APPENDIX 7
Glossary
MOSSMORRAN & BRAEFOOT BAY INDEPENDENT AIR QUALITY
MONITORING REVIEW GROUP
2008 Annual Report
1. INTRODUCTION
The Mossmorran & Braefoot Bay Independent Air Quality Monitoring Review Group (the
Review Group) was formed to provide advice and recommendations to Fife Council (formerly
Fife Regional Council and Dunfermline and Kirkcaldy District Councils) regarding the
monitoring of air emissions arising from the operations at the Mossmorran plants and the
Braefoot Bay terminal facilities (operated by Shell UK Limited and ExxonMobil Chemical
Limited). The constitution and terms of reference of the Review Group are described in
Appendix 1. Appendix 2 lists the members of the Review Group during 2008.
Shell UK operates the Mossmorran Gas Fractionation Plant that extracts natural gasoline,
ethane, propane and butane from natural gas liquids pumped from the St Fergus gas plant
at Peterhead. The plant at Mossmorran comprises three identical process units fed directly
from the pipeline. Large atmospheric pressure tanks store propane, butane and gasoline.
These products are supplied by underground pipeline to the Braefoot Bay deep water
loading facility, where they are loaded on to tankers. Ethane is piped to feed the Fife
Ethylene Plant (operated by ExxonMobil) and to the BP site at Grangemouth. The plant also
supplies approximately 5% of the total propane and butane to the Shell Gas Road Loading
Terminal. The ExxonMobil Chemical Fife Ethylene Plant is one of Europe's largest and most
modern ethylene plants. It has the capacity to produce 830,000 tonnes of ethylene a year.
Previous air quality monitoring demonstrated that concentrations of benzene and other
hydrocarbons were low in the vicinity of the facilities. The Review Group concluded in 1999
that its work was nearing completion and that further air quality monitoring was probably not
required. However, the Review Group was reconstituted in 2001 following concern
expressed by local communities, and highlighted in media reports, with regard to perceived
air quality and cancer-related health issues in the vicinity of Mossmorran and Braefoot Bay.
The Review Group continues to liaise with local communities and representatives of the local
health service.
The aims of this Annual Report are to:
Outline any substantive changes in the facilities at Mossmorran and Braefoot Bay
and their likely impact on local air quality;
Describe any changes in air quality regulation and changes in knowledge on health
effects of benzene or any other possible emissions from the plants;
Comment on the results of ambient air quality monitoring undertaken by the National
Physics Laboratory (NPL), on behalf of BP Exploration Operating Company Ltd, in
terms of air quality policy, plant operations and risks to health in the local community;
Comment on the emissions from point sources at the facilities;
Summarise the available data on flaring during 2008;
Review the local air quality measurement study that was undertaken by NPL on
behalf of ExxonMobil during a period of planned flaring.
Page 3 of 20
2.
OBSERVATIONS
The main observations of the Review Group in 2008 were as follows.
i)
There were no significant changes in the plant or its operation during 2008.
ii)
There have been no changes in the regulations governing air quality management
and the prevention and control of emissions to air. The Technical Guidance for local
authorities in relation to Local Air Quality Management was revised during 2008 but
this has no implications for the operations at Mossmorran and Braefoot Bay which
are regulated by the Scottish Environment Protection Agency (SEPA). SEPA have
developed a new scheme to assess operator compliance which is being implemented
from the beginning of 2009. In the future, good operator compliance may be
rewarded by a lowering of inspection frequency and the fees paid to SEPA (Appendix
3).
iii)
Emissions from all regulated sources at Mossmorran and Braefoot Bay in 2008 were
below the emission limits set by SEPA (Appendix 4). Emission limits are set to
ensure that the impact of emissions are minimised through the efficient operation of a
process. As it can be difficult to monitor a substance once it has been released into
the atmosphere, operators are required to carry out periodic measurements of gases
before they exit the stacks. Emission Limit Values (ELVs) are specified in a Permit or
Authorisation and generally focus on the principal emissions from industrial
processes where control is necessary. ELVs can be a direct requirement of
legislation, set in connection with what is achievable in terms of Best Available
Techniques, or be generated on a site specific basis. ELVs are set for the protection
of human health and the environment.
iv)
NPL, on behalf of BP Exploration Operating Company Ltd, reported on 12 months of
air quality monitoring around Hound Point (from 04/01/08 to 31/12/08). These
measurements are made in order to provide information about the impact of BP’s
operation at Hound Point on local air quality. Measurements were made at twelve
sites on the south coast of Fife, between North Queensferry and Burntisland.
Samples are collected over two-week periods throughout the year. The
measurements made in 2008 are not directly comparable with those made in
previous years because samples were collected on a different type of sorbent
material giving an improved retention of lower molecular weight compounds. As a
result of this methodological change, the concentrations of some compounds
(isobutene, n-butane, isopentance, n-pentane) appear to be higher than previously
reported. After taking account of the change in sorbent material, the concentrations
of volatile organic compounds (VOCs) measured in most samples are believed to be
similar to those measured in previous years. Samples collected near The Old Battery
in North Queensferry, however, showed an increase in concentration since last year
and concentrations of all the measured VOCs were higher than those measured
elsewhere. The average benzene concentration at this location was 0.6 ppb, well
below the current National Air Quality objective of 5 ppb (16.25 µgm-3) and the 2010
objective of 1ppb (3.25 µgm-3), but higher than at the other locations where
monitoring was performed (0.2-0.4 ppb). Mean concentrations of total hydrocarbons
over 12 months ranged from 5 ppb at The Belvedere Hotel in West Wemyss to 46
ppb near the Old Battery. Mean concentrations of n-hexane, n-heptane, toluene and
xylene were less than 1 ppb at all locations including the Old Battery. Mean
concentrations of iso-butane were generally less than 2 ppb but were 5.8 ppb at the
Old Battery. Similarly, concentrations of n-hexane were generally less than 1 ppb but
2.2 ppb at the Old Battery. Concentrations of n-butane, iso-pentane and n-pentane
Page 4 of 20
ranged from 1.1 to 30.8 ppb by pollutant and location with the highest mean
measurements for each pollutant reported for the Old Battery. The second highest
mean measurements reported for each of the pollutants were generally made at the
Queensferry Lodge Hotel, North Queensferry. Although hydrocarbon concentrations
at these locations were not clearly elevated in comparison to the other sites in 2007,
higher levels of hydrocarbon have been reported at these locations in the more
distant past, notably in 2001/2002.
v)
The quantities of gas flared in 2008 were greater than in 2007 but within the range
reported in previous years (Appendix 5). Some flaring occurred in each month with
increased levels during April, August and October with the latter two periods being
associated with planned maintenance (Appendix 5). It is noticeable that the quantities
flared over the last three years have been substantially greater than in 2005 or
previously between 2001 and 2003.
vi)
ExxonMobil recently commissioned a study of air quality around the Mossmorran
complex before, during and after a period of planned maintenance and related flaring
activity. The study assessed the quality of the air at 8 different locations, including
three residential areas (Lochgelly, Auchertool and Castlehill, near Cowdenbeath). A
range of pollutants were monitored, including benzene and particulate matter
(microscopic material that is carried in the atmosphere). The assessment was carried
out by the National Physical Laboratory between 21 August and 1 October 2008. The
monitoring study concluded that there was no evidence to show that maintenance
and flaring activities on the Mossmorran site were having a detrimental impact on
local air quality (Appendix 6).
vii)
Fife Council’s air quality review and assessment progress report for 2007/8 indicates
that national air quality objectives are expected to be met in the area around
Mossmorran and Braefoot Bay for all pollutants included in the Air Quality Standards
(Scotland) Regulations 2007. [To date, only one Local Air Quality Management Area
has been declared in Fife. It is over 20 miles from Mossmorran at Bonnygate, Cupar,
where air quality objectives are exceeded for nitrogen dioxide and PM10 as a result of
traffic emissions.]
viii.
ExxonMobil have introduced an e-mail communication which is sent to key contacts if
flaring or unusual operations are taking place. The aim of this communication is to
provide additional information and not to replace the phone messages presently
made to key contacts.
Page 5 of 20
3.
CONCLUSIONS
i)
Emissions from regulated sources within the plants in 2008 remained well below the
limit values set by SEPA for the protection of public health and the environment.
ii)
These results are consistent with the previous work of the Review Group. In the
areas around Mossmorran and Braefoot Bay the 2010 air quality objective for
benzene is being satisfied readily.
iii)
The quantities flared during 2008 were higher than in 2007 but within the range
reported previously. The results of an air quality measurement survey undertaken
during a period of planned plant shutdown indicated that the impacts of flaring on
local air quality were negligible.
iv)
The work undertaken in 2008 demonstrates that emissions from Mossmorran and
Braefoot Bay continue to pose no significant risk to the health of the local community.
Page 6 of 20
APPENDIX 1
The Review Group: Constitution and Terms of Reference
The Review Group reports to Fife Council which requires its operating costs to be financed by
ExxonMobil Chemical Limited (ExxonMobil) and Shell UK Limited (Shell). Review Group members
are appointed by Fife Council.
Professor Sibbett continues as Independent Chair, with representatives from Fife Council, SEPA and
the Institute of Occupational Medicine participating as members. The Review Group also includes
representation in public health from the Dunfermline and West Fife Community Health Partnership
(formerly West Fife Local Health Care Co-operative) on behalf of NHS Fife and two members
represent the local Community Councils. This is designed to ensure that timely and informative
communications can be provided in respect of any relevant health issues that might arise in the local
communities. Representatives of ExxonMobil and Shell attend the Review Group meetings by
invitation.
The full constitution and terms of reference of this reconstituted group are given below. Briefly, the
Review Group’s approach to carrying out its functions has been re-assessed, allowing it to take less
involvement in the monitoring of air quality, but instead to focus attention on the review of such data.
Of particular relevance are issues relating to any health concerns raised by residents within the local
communities and a key role is assisting with the communication of information relating to
environmental air quality.
Detailed Constitution and Terms of Reference
1.0
TITLE
1.1
The Group is known as the Mossmorran & Braefoot Bay Independent Air Quality Monitoring
Review Group (referred to below as the Review Group).
2.0
INTRODUCTION
2.1
The Review Group was formed to provide advice and recommendations to Fife Council
(formerly Fife Regional Council and Dunfermline and Kirkcaldy District Councils) regarding
the monitoring of air emissions arising from the operations at the Mossmorran plants and the
Braefoot Bay terminal facilities. Specific terms of reference which previously pertained were
as required by planning conditions applying to the operation of the plants.
2.2
The Review Group’s approach to carrying out its functions has been re-assessed, allowing it
to take less involvement in the monitoring of air quality, with its primary responsibilities being
re-directed towards reviewing such data. Of particular relevance are issues relating to any
health concerns raised by residents within the local communities, and a key role is assisting
with communications of air quality related information.
3.0
TERMS OF REFERENCE
3.1
The Review Group (as reconstituted in terms of para. 2.2 above) has the following remit:
(i)
To provide advice on air quality related monitoring arrangements.
(ii)
To review air quality monitoring data obtained at sites in the vicinity of the
Mossmorran complex and the Braefoot Bay terminal.
(iii)
To consider, advise and make recommendations on the outcome of monitoring data.
The Review Group intends by inclusion in its membership of public health
representation that timely and informative communications can be provided in respect
of any relevant health issues that might arise in the local communities.
Page 7 of 20
(iv)
To submit reports to Fife Council and to make presentations as appropriate to
representatives of the Community Councils that are local to the Mossmorran plants
and the Braefoot Bay terminal. The Review Group intends inclusion in its
membership of representation from the local Community Councils to assist with this
communications related responsibility.
3.2
These terms of reference shall not imply any responsibility for, control over, or restriction of
the statutory or common law positions of Fife Council, Shell UK Limited (Shell), ExxonMobil
Chemical Limited (ExxonMobil), or any other local authority, statutory authority or agency, or
company, or institution, nor derogate from the rights, powers and responsibilities of such
authorities, agencies, companies or institutions.
4.0
APPROACH
4.1
The Review Group’s approach will be based on:
(i)
Making the Minutes of its meetings publicly available;
(ii)
Ensuring that all reports produced by, or on behalf of, the Review Group are fully
documented and contain source references to all relevant data;
(iii)
Providing regular and non-technical summaries on its activities;
(iv)
Informing the local communities through submissions to existing liaison structures
(i.e. primarily the Mossmorran & Braefoot Bay Community & Safety Committee) and
through direct presentations by Review Group members as appropriate, and
(v)
Being open to approaches from local communities and individuals.
5.0
MEMBERSHIP
5.1
Membership of the Review Group comprises appropriate representation from the following:






An Independent Chair
Fife Council officials
Institute of Occupational Medicine (IOM)
Scottish Environment Protection Agency (SEPA)
Public health services
Community Councils on the Mossmorran & Braefoot Bay Community & Safety
Committee (inland and coastal)
5.2
The Review Group will invite representatives of Shell and ExxonMobil to attend meetings, and
may invite others to address group members on issues related to the terms of reference set
out at para. 3.1 above.
5.3
The Review Group Secretary (see para. 6.2 below) shall maintain a current register of
members, for distribution and information purposes.
5.4
ExxonMobil maintains a list of Community Council contacts who are notified of flaring.
6.0
OFFICE BEARERS
6.1
The Independent Chair may be nominated by any member of the Review Group. If any
change in the appointment as Chair is proposed, the agreement of Fife Council will be
required.
6.2
The Review Group approves the appointment of a Secretary, who prepares a record of
meetings and is responsible, in consultation with the Chair, for preparing agenda papers,
summoning the meetings, and circulating a record of meetings to the membership.
Page 8 of 20
6.3
The finalisation of reports by the Review Group shall be as determined by the Chair.
7.0
MEETINGS
7.1
The Review Group will meet as frequently as is considered necessary by the Chair (normally
at least once a year), having regard to the remit set out at para. 3.1 above.
7.2
The Secretary shall send to all members and others, as appropriate, a record of the previous
meeting, together with notice and agenda papers for all meetings of the Review Group, at
least seven days before the day of the meeting.
7.3
Business shall be in keeping with the terms of reference set out at para. 3.1 above.
8.0
FINANCE
8.1
The companies, having met the cost of monitoring work previously undertaken in fulfilment of
planning conditions, shall meet relevant costs based on the advice of the Review Group.
8.2
The local authority shall meet any reasonable costs of the administration of the Review
Group.
Page 9 of 20
APPENDIX 2
Membership of the Review Group (as at December 2007)
Name
Designation/
Representing
Address
Prof. Wilson Sibbett
Independent Chair
School of Physics & Astronomy,
University of St Andrews
Stuart Wilson
Interim Team Leader
(Development, Promotion and
design) Fife Council
Development Services,
Dunfermline
Douglas Mayne
Fife Council (Environmental
Services)
Environmental Services,
Glenrothes
Liz Box
Committee Administrator, Fife
Council
Democratic Services,
Dr Alison Searl
Institute of Occupational Medicine
(IOM)
Edinburgh
Michelle Hickson
Scottish Environment Protection
Agency (SEPA)
Perth
Lynn Campbell
Dunfermline & West Fife
Community Health Partnership
Lynebank Hospital, Dunfermline
Robert Arnott
Crossgates & Mossgreen
Community Council
Crossgates (Inland)
William Dryburgh
Aberdour Community Council
Aberdour (Coastal)
Barry Jarvis
Shell UK Limited
Fife NGL Plant, Mossmorran
Norman White
Shell UK Limited
Fife NGL Plant, Mossmorran
Alex Baird
Shell UK Limited
Fife NGL Plant, Mossmorran
Ian Hackers
ExxonMobil Chemical Limited
Fife Ethylene Plant, Mossmorran
William Sweenie
ExxonMobil Chemical Limited
Fife Ethylene Plant, Mossmorran
Kenny Bisset
Fife Council (Environmental
Services)
Environmental Services,
Glenrothes
Dr. Alastair
Robertson
Institute of Occupational Medicine
Edinburgh
John Lamb
Air Quality Management
Specialist, SEPA
Edinburgh
Dr Jackie Hyland
NHS Fife, Cameron Hospital
Leven, Fife
Linda Whetren
NHS Fife
A. MEMBERS
B. BY INVITATION
Page 10 of 20
Fintan Hurley
Institute of Occupational Medicine
Edinburgh
Chris Rushton
Auchtertool Community Council
Auchtertool
Alexander
Macdonald
Burntisland Community Council
Burntisland
David Taylor
Cardenden & Kinglassie
Community Council
Cardenden
Alex Haddow
Cowdenbeath Community
Council
Cowdenbeath
Colin McPhail
Dalgety Bay & Hillend Community
Council
Dalgety Bay
Ernest McPherson
Lochgelly Community Council
Lochgelly
Page 11 of 20
APPENDIX 3
Regulatory and Policy changes relating to air quality in 2008
There were no changes in regulation relating to air quality in Scotland during 2008. The
technical guidance for local authorities on how to undertake assessments to meet their
obligations with respect to Local Air Quality Management under the Environment Act, Part IV
(1995) was revised during 2008. A draft copy of the revised guidance made available as
TG(08). There are no implications arising from the revised guidance for the operations at
Mossmorran and Braefoot Bay which are regulated by the Scottish Environment Protection
Agency (SEPA).
During 2008, SEPA adopted a “Better Regulation Initiative” which aims to reduce the
administrative burden and costs to operators and to improve the consistency, transparency
and accountability of regulation. As part of this initiative, SEPA is introducing a new
compliance assessment scheme in 2009. The aim of the new scheme is to create a
consistent approach across various regulatory regimes. It will be used to assess compliance
with the Radioactive Substances Act 1993 (RSA), waste management legislation, the
Pollution Prevention and Control (Scotland) Regulations 2000 (PPC) and the Water
Environment (Controlled Activities) (Scotland) Regulations 2005 (CAR). The scheme will not
apply to the Control of Major Accident Hazard Regulations (COMAH). The new compliance
scheme will be phased in across the different regimes regulated by SEPA and gradually
replace the existing Operator Performance Assessments (OPA). The scheme will apply to
Pollution Prevention and Control (PPC) from January 2009, resulting in the first assessments
of these permits being produced in spring 2010. The final OPA for PPC activities for
calendar year 2008 will be completed in the first half of 2009. The new scheme is not directly
linked to inspection frequency in the way that the current OPA scheme is. The performance
of the site will have an impact on the regulatory effort applied to the site and this may well
take the form of additional inspections where poor compliance is observed. In the future, the
compliance assessment may also be used as a basis to reward operators achieving a high
level of compliance through a lowering of their annual permit charges (subject to the
outcome of a consultation process to be completed in 2009). The scheme will not alter the
basic content of permits.
Page 12 of 20
APPENDIX 4
Regulated emissions to air

Emissions from all regulated sources at Mossmorran and Braefoot Bay
during 2008 were well below the limits set by SEPA.
SEPA authorises the operations carried out by both Shell and ExxonMobil at Mossmorran
under the Pollution Prevention and Control (Scotland) Regulations 2000 (PPC). The PPC
permits are based on the concept of Integrated Pollution Prevention and Control (IPPC) and
define limits for emissions from the facilities at Mossmorran to air, water and land. SEPA has
set permit conditions that ensure that Best Available Techniques are being employed by the
companies to prevent or generally reduce the impact of emissions on the environment.
ExxonMobil’s vapour control unit at Braefoot Bay is authorised under the Environmental
Protection Act 1990.
For airborne emissions from Mossmorran, the Shell and ExxonMobil permits concentrate on
stacks from furnaces, boilers and a gas turbine. They define emission limits for each
regulated source and set out sampling and reporting regimes for assessing compliance with
these limits. The companies must report results to SEPA’s Strathearn Office in Perth for
appraisal. SEPA also make these results available in a public register.
The emissions monitoring measurements for 2008 submitted to SEPA are summarised for
each regulated Shell and ExxonMobil source at Mossmorran in Tables A4.1 and A4.2
respectively, and for Braefoot Bay in Table A4.3. The emission limits, authorised by SEPA
for each emission source, are also listed in these tables. During 2008, emissions from all
regulated sources at Mossmorran were well below the limits set by SEPA.
Table A4.1: Emissions from Regulated Shell Sources at Mossmorran during 2008
CO Concentration (mg/m3)
NOx Concentration
(mg/m3)
SO2 Concentration
(mg/m3)
Authorised
Emissions
Limit
2008
average
Authorised
Emissions
Limit
2008
average
Authorised
Emissions
Limit
2008
average
Furnace
1
100
<20
150
73.8
10
0.62
Furnace
2
100
<20
150
86.2
10
0.20
Furnace
3
100
<20
150
75.0
10
0.68
Page 13 of 20
Table A4.2: Emissions from Regulated ExxonMobil Sources at Mossmorran during
2008
CO Concentration
(mg/m3)
Authorised
PPC
Emissions
Limit
no limit
no limit
no limit
no limit
no limit
no limit
no limit
2008
Average
nm
nm
nm
nm
nm
nm
nm
Furnace 1
Furnace 2
Furnace 3
Furnace 4
Furnace 5
Furnace 6
Furnace 7
Gas Turbine
Stack
no limit
nm
Boiler A
200
0.0
Boiler B
200
0.0
Boiler C
200
0.0
No limit: no emission limit applied by SEPA
nm: not measured
NOx Concentration
(mg/m3)
Authorised
PPC
Emissions
350
350
350
350
350
350
350
550
350
350
350
SO2 Concentration
(mg/m3)
2008
Average
88.9
103.7
99.4
93.3
108.0
91.2
170.9
Authorised
PPC
Emissions
Limit
no limit
no limit
no limit
no limit
no limit
no limit
no limit
2008
Average
nm
nm
nm
nm
nm
nm
nm
148.0
107.6
132.1
122.1
no limit
no limit
no limit
no limit
nm
37.4
14.3
0.5
Table A4.3: Emissions of Benzene and Total Hydrocarbon from ExxonMobil Regulated
Source at Braefoot Bay (Vapour Control Unit) measured in 2008
Benzene (mg/m3)
VOCs (ppm)
(Authorised Limit = 10
mg/m3)
(Authorised Limit = 20
mg/m3)
04-Jan-081
1.4
8.7
02-Feb-08
0.1
0.0
24-Mar-08
0.6
0.1
26-May-08
<0.04
<0.05
29-May-08
<0.05
<0.05
30-Jul-08
<0.043
<0.1
31-Jul-08
<0.045
<0.1
19-Dec-08
<0.07
<0.1
Date
January 2008 readings were taken with a portable analyser known to over-estimate concentrations of
VOCs. The January measurement is expressed in ppm, not mg/m 3. From February 2008 onwards,
concentrations were measured by an external consultant using more accurate procedures.
Page 14 of 20
APPENDIX 5
2008 Flaring Report
A5.2
ExxonMobil Fife Ethylene Plant
Table A5.1, below, indicates the quantities flared during 2008. There were a number of
periods of planned and unplanned maintenance that led to plant shutdown and flaring during
the year.
Table A5.1 Quantities Flared from the ExxonMobil Fife Ethylene Plant
Flaring from
Planned Start
Up/Shutdown
Flaring
Month
Flaring from
Routine, Normal
Baseline
Operations
Flaring from
Abnormal or Non
Routine
Operations
Elevated
Flare
Tonnes
Flared
Ground
Flares
Tonnes
Flared
Elevated
Flare
Tonnes
Flared
Ground
Flares
Tonnes
Flared
Elevated
Flare
Tonnes
Flared
Ground
Flares
Tonnes
Flared
0
0
0
496
2572
667
April
0
0
2800
0
0
1247
7
0
0
266
397
470
613
0
0
324
0
0
May
0
0
21
528
0
0
June
0
0
58
387
0
0
August
0
1425
0
726
0
53
376
549
0
0
0
0
September
2832
4160
0
345
0
0
November
0
0
0
0
0
6
405
359
0
2282
0
2200
December
0
0
4
298
632
240
January
February
March
July
October
Event Reason
Process Compressor R-C-01
unplanned shutdown.
Valve positioner maintenance
No events
Plant shutdown for essential
maintenance
Shell Ground Flares out of
service for maintenance
Shell Ground Flares out of
service for maintenance
Plant shutdown for essential
maintenance
Plant shutdown for essential
maintenance
No events
Gas
Turbine
unplanned
shutdown
The quantity flared varies from year to year depending on circumstances and the quantity
flared in 2008 was greater than in 2007 (7,797 tonnes elevated flares, 10,563 tonnes ground
flares) but within the range reported in earlier years as shown in the graph below. It is
noticeable that the quantities flared over the last three years have been substantially greater
than in 2005 or previously between 2001 and 2003.
Page 15 of 20
40000
Tonnes flared
35000
30000
25000
20000
15000
10000
5000
0
1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008
Year
A5.2
Shell Natural Gas Liquefaction Plant
A total of 392 tonnes of gas was flared from the Shell NGL plant during 2008. There were
no unplanned flaring events during 2008, with all flaring from the NGL plant arising during
planned maintenance and routine events. Table A5.1 summarises the monthly flaring from
the NGL plant.
Table A5.2 Quantities flared from the Shell Natural Gas Liquefaction Plant during 2008
Month
January
February
March
April
May
June
July
August
September
October
November
December
TOTALS
Tonnes Flared
31.8
32.8
27.3
17.2
24.7
41.6
36.1
65.6
25.6
24.2
34.0
31.4
392.3
Page 16 of 20
APPENDIX 6
Atmospheric Monitoring Study at ExxonMobil Fife
Ethylene Plant Mossmorran
Non Technical summary
______________________________________________________________
Introduction
1) ExxonMobil recently commissioned a study of air quality around the Mossmorran
complex before, during and after a period of planned maintenance and related flaring
activity. The study assessed the quality of the air at 8 different locations, including three
residential areas. The assessment was carried out by the National Physical Laboratory
between 21 August and 1 October 2008.
2) It was important to ensure that the monitoring devices were positioned at locations where
pollutants are most likely to be carried by the wind. Whilst the prevailing wind in Fife
generally comes from the south west, north easterly winds are also quite common.
Monitoring devices were therefore located in Lochgelly, Auchertool and Cuttlehill (near
Cowdenbeath). A range of pollutants were monitored, but the two of most concern (with
regards to human health) were benzene and particulate matter (microscopic material that
is carried in the atmosphere).
Benzene
3) The measured concentrations of benzene in the residential areas when flaring was
underway were almost identical to those that were obtained when there was no flaring in
progress. There was no evidence to show that flaring activity increased the
concentrations of benzene at the residential areas.
4) The measured concentrations of benzene at the residential areas were consistently
lower than the maximum permitted level that has been introduced to protect human
health. This Scottish air quality standard is more stringent than the one that applies in
England, Wales and other parts of Europe.
Particulate Matter
5) The monitoring study measured the concentrations of microscopic material carried in the
atmosphere. If the activities on the Mossmorran site were adding to the local
concentrations, this would have been detected by the monitoring device that was located
downwind of the plant at the time. However, the study found that monitors at all locations
measured similar concentrations over the same time period, thus suggesting that the
material is likely to have been carried in from areas outside Fife. This ‘background’ level
will consist of a wide range of materials that have been created by human and natural
activities (for example: dust from agricultural activities, sea salt, smoke from domestic
fires, fungal spores and sand from the Sahara).
6) Again, the Scottish air quality standards for particulate matter are more stringent than
those that apply to the rest of the United Kingdom and Europe. The measured
concentrations indicate that the local concentrations of particulate matter were lower
than the maximum permitted levels that have been set to protect the most sensitive
individuals in society.
7) The Scottish Government has published a method (1) that is used to assess how a
pollutant is likely to affect a person who is sensitive to the effects of air pollution. All the
1)
http://www.scottishairquality.co.uk/about.php?n_action=standards&t=5
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measured concentrations of particulate matter are typical of a rural environment and they
all fell into the lowest categories of the Air Pollution Bandings and Index.
8) There is no evidence to indicate that the activities on the Mossmorran site were making a
measurable contribution to the levels of particulate matter in the residential areas.
Other Hydrocarbons
9) The assessment also measured a range of hydrocarbons that included 1,3-butadiene.
These concentrations were generally so low, that they could not be detected by the
monitoring equipment.
Conclusion
10) The monitoring study concluded that there was no evidence to show that maintenance
and flaring activities on the Mossmorran site were having a detrimental impact on the
quality of the air in Lochgelly, Auchtertool or Cuttlehill. A copy of the monitoring study
was submitted to Fife Council’s Environment Enterprise and Transportation Committee
on 28th May, 2009.
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APPENDIX 7
GLOSSARY
Concentration Units
ppb: parts per billion by volume, concentration unit for gases and vapours, equivalent to one
cubic millimetre of gas mixed with one cubic metre of air.
ppm: parts per million by volume, concentration unit for gases and vapours, equivalent to
µg/m3: microgram per cubic metre, mass concentration unit for particulates and gases.
There are 1,000,000 micrograms in a gram and 25,000,000 micrograms in an ounce.
mg/m3: milligram per cubic metre, mass concentration unit for particulates and gases. 1
mg/m3 = 1,000 g/m3.
Pollutants
PM10: This is the fine fraction of airborne dust, defined by international convention, that can
be deposited in the lung. It is the fraction of airborne dust around which the UK air quality
standard is defined. There are many sources, including road traffic, agriculture, industry and
many personal activities. It includes particles that are approximately less than 10 μm in
diameter.
PM2.5: This is a subfraction of PM10 sometimes referred to as “high risk respirable”. It is the
fraction of airborne particles that can penetrate to the gas exchange region of the lungs in
those with compromised respiratory health. PM2.5 is largely comprised of particles generated
by combustion plus particles that form as a result of reactions in the atmosphere. These
include particles that form from sulphur dioxide and nitrogen oxides.
Benzene: This aromatic hydrocarbon is a minor component of petrol. Fuel distribution and
car exhausts are its most important environmental source. It is present in cigarette smoke,
some foods and drinks and widely in nature. Benzene is recognised as causing cancer in
people.
1,3-Butadiene: Butadiene is a hydrocarbon that arises in air solely from human activity. It is
an important industrial chemical, being used in synthetic rubber manufacture and is found in
some liquid petroleum gases. Its main sources in the environment are, however, from road
traffic emissions. It is considered as capable of causing cancer in people.
Nitrogen Dioxide: This gas is produced by the reaction of oxygen and nitrogen during
combustion. Vehicle emissions are a major source. It is well known as an irritant and, more
recently, has been found to affect health at concentrations that can be found in the
environment and indoors. Nitric oxide always occurs when nitrogen dioxide is formed. The
two gases together are known as oxides of nitrogen, sometimes described in shorthand form
as NOx..
VOCs or Volatile Organic Compounds: Carbon-based (or organic) chemicals that readily
evaporate. Many hydrocarbons, including benzene, butane, pentane and hexane are VOCs.
Organisations/facilities
SEPA: Scottish Environment Protection Agency
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FEP: Fife Ethylene Plant - ExxonMobil Chemical Limited (ExxonMobil)’s production facility at
Mossmorran and ExxonMobil’s Braefoot Bay Marine Terminal.
Fife NGL Plant: Fife Natural Gas Liquids Plant – comprises Shell UK Limited (Shell)’s
production facility at Mossmorran for the fractionation of liquefied natural gas, and Shell’s
Braefoot Bay Marine Terminal.
NPL: National Physical Laboratory
Other
ELV: Emission Limit Value
PPC: Pollution Prevention and Control
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