ENVIRONMENTAL ASSESSMENT
OF GAS ASSET
- 2002 REVIEW AND UPDATE
PETROLEUM DEVELOPMENT OMAN
SULTANATE OF OMAN
Petroleum Development Oman
Gas Asset
Environmental Assessment
2002 Review and Update
Authorized for release by:
Dr. L. M. Akella
Senior Consultant
Date: 12 July 2003
PETROLEUM DEVELOPMENT OMAN
ENVIRONMENTAL ASSESSMENT OF GAS ASSET
- 2002 REVIEW AND UPDATE
HMR Environmental Engineering Consultants
P.O. Box: 1295, CPO Seeb
Postal Code: 111
Sultanate of Oman
Tel: (968) 502506
Fax: (968) 502616
email: [email protected]
www.hmrenv.com
July 2003
©HMR Environmental Engineering Consultants
Oman’s Environmental Consultancy
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Environmental Assessment
2002 Review and Update
EXECUTIVE SUMMARY
Introduction
This report updates the environmental assessment of Gas asset, which is one of the service
assets within PDO's concession area in the Sultanate of Oman. The first environmental
assessment for Gas asset was carried out in September 1999. Since then, several changes with
respect to the facilities, processes and procedures have taken place in the asset. In order to
review the impacts on the environment due to these changes, the environmental hazards and
effects associated with the activities in the asset are reassessed in this study. This study is
conducted, on behalf of PDO by HMR Environmental Consultants during the period of JuneDecember 2002.
Overview of Asset Activities and Facilities
PDO operates over 113,550 km2 of concession area consisting of about a hundred fields,
2,454 oil producing wells and 72 gas producing wells. Currently, PDO produces 843,490
barrels/day of crude and 44 million Sm3 of gas on average per day.
Gas asset is one of the service providers in PDO. It is primarily responsible for providing
support services to an external customer, viz., the government of the Sultanate of Oman,
represented by Oman Gas Company SAOG. On behalf of the government, gas asset operates
and maintains gas handling and treatment facilities within PDO’s concession area gas plant in
Yibal, butane plant located in Yibal, butane storage and loading facility in Yibal, central gas
processing plant in Saih Rawl, gas treatment plant in Saih Nihayda, and gas gathering station
in Barik.
Gas asset works under the overall direction of the Deputy Managing Director, and at the asset
level it is managed by the Gas Manager.
Description of Environment
The facilities operated and maintained by gas asset are located in Yibal, Saih Rawl, Saih
Nihayda and Barik. While Yibal is located within Yibal asset area, Saih Rawl, Saih Nihayda
and Barik are located within Qarn Alam asset area.
The topographical features of Yibal are characterized by flat featureless gravel plains and low
gravel hills with a few rocky outcrops. Low un-stabilized sand dunes and shallow wadis are
also present. The southern part of the asset is a part of a large Sabkha called the Umm as
Samim.
The topography and landscape Qarn Alam is characterised by flat plains interspersed with
small drainage channels and occasional rocky outcrops. The elevation with reference to the
mean sea level ranges from about 140 m. There is one major wadi (Wadi Umayri), which
drains in the north west of the asset, and other smaller wadis (Wadi Majhul, Halibah, Thaylah
and Wadi Qitfah).
Yibal asset area is composed of alluvial gravel and aeolian sand, underlain by chalk and marl.
The underlying rock is almost horizontal mid-tertiary limestone from the Oligocene and
Miocene era. The aquifer system in Yibal is composed of Fars, Dammam, Rus and UeR
formations.
The geology of Qarn Alam comprises mainly of carbonates and clastics and the groundwater
exists in Fars and UeR formations, which is the only water resource in the region.
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The climate in Yibal and Qarn Alam are similar to that in Fahud. The area is characterized by
an arid climate with mean monthly temperatures range from 19.1oC in January to 35.5oC in
June, and extreme temperatures ranging from a maximum of 47.9oC to a minimum of 7oC.
The mean annual rainfall in Qarn Alam area is 1.1 mm.
The native vegetation is composed of desert plants and grasses, and trees, which are rarely
seen. The fauna include a few species of largest mammals including the mountain gazelle and
the Rheem gazelle, both of which qualify under the IUCN world Red List and the regional
Red List threat categories. A few smaller mammals, mostly gerbils, 96 species of birds and
jerboas are likely to be present in the vegetated areas.
There are no major settlements in Yibal asset outside the PDO camp, except for Wadi Al
Umairy. This village has 27 household with a total population of 102 persons. Other than this
village, there are no towns or Bedouin settlements within the asset area.
While in Qarn Alam, there are no towns within the asset area and Bedouin (nomadic or seminomadic) settlements are relatively few in number and nowhere permanent. A total of
approximately 20 families are known to PDO in the area.
The literature search and a walk-through field survey have shown no evidence of
archaeological sites in Qarn Alam asset. Within Yibal asset, Umm as Samim, the largest
sabkha of the Arabian Peninsula, and one of the largest in the world.
Significant Environmental Effects
Based on the existing activities and the current status of the environment in the asset, the
environmental hazards and potential effects are identified. The potential environmental effects
are assessed based on the HEMP methodology outlined in PDO's document GU-195
"Environmental Assessment Guideline". The effects with a risk rating level of medium or
higher are short-listed and the necessary additional mitigation measures are recommended.
The following table summarizes the recommended additional mitigation measures against
each of the environmental specifications of PDO, viz., SP-1005 to SP-1012 and SP-1170.
Specification
SP-1005: Specification
for
Emissions
to
Atmosphere
SP-1006: Specification
for Aqueous Effluents
SP-1007: Specification
for Accidental Releases
to Land and Water
SP-1008: Specification
for Use of Energy,
Materials and Resources
SP-1009: Specification
for Waste Management
SP-1010: Specification
for Environmental Noise
and Vibration
Areas of Non-compliance or
Concern
• No monitoring data are available
demonstrating compliance with
workplace and ambient air
quality standards in and around
gas processing facilities.
• None
Recommended
Additional
Mitigation Measures
• Work place and ambient air
quality shall be monitored
periodically in and around gas
processing facilities.
• Accidental leaks and spills of oils
and chemicals are not monitored
and reported.
• Efficient use of fuel and water in
the field activities of the asset is
not demonstrated.
• None
• All accidental leaks and spills
shall be monitored and
reported.
• Fuel conservation measures
shall be promoted.
• No monitoring data are available
demonstrating compliance with
workplace and ambient noise
standards in and around gas
processing facilities.
• Work place and ambient noise
levels shall be mo nitored
periodically in and around gas
processing facilities.
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• None
• None
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Specification
SP-1011: Specification
for Flora and Fauna
SP-1012: Specification
for Land Management
SP-1170: Specification
for Management of
Naturally
Occurring
Radioactive Materials
Areas of
Concern
• None
Environmental Assessment
2002 Review and Update
Non-compliance or
Recommended
Additional
Mitigation Measures
• None
• None
• None
• None
• None
Conclusion
Based on the present study, it is concluded that no change in PDO’s existing HSE
management system is required. However, it is necessary to modify the HSE plans and
programmes in the asset by incorporating the additional mitigation measures recommended
above. This will ensure that the potential environmental risks are minimized, noncompliances are eliminated and the overall environmental performance in the asset is
significantly improved.
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TABLE OF CONTENTS
Section
1
Title
Page
ABBREVIATIONS
(vii)
INTRODUCTION
1.1
1.2
1.3
1.4
1.5
2
Petroleum Development Oman
Environmental Impact Assessment
Objectives and Scope of Study
Method of Study
Structure of Report
C1-1
C1-4
C1-6
C1-6
C1-6
REGULATORY FRAMEWORK
2.1
2.2
2.3
2.4
3
Omani Regulations
Shell Group Environmental Guidelines
PDO Corporate Environmental Specifications
Environmental Standards
C2-1
C2-2
C2-2
C2-3
ASSET DESCRIPTION
3.1
3.2
3.3
3.4
3.5
3.6
3.7
3.8
4
Introduction
Government Gas Plant
Government Butane Plant
Butane Storage and Loading Facility
Central (Gas) Processing Plant
Saih Nihayda Gas Treatment Plant
Barik Gas Gathering Station
Materials and Utilities
C3-1
C3-1
C3-4
C3-6
C3-6
C3-7
C3-10
C3-11
RELEASES TO ENVIRONMENT
4.1
4.2
4.3
4.4
4.5
4.6
5
Introduction
Air Emissions
Liquid Effluents
Solid Wastes
Noise
Accidental Leaks and Spills
C4-1
C4-1
C4-6
C4-6
C4-7
C4-8
ENVIRONMENTAL SETTING
5.1
5.2
5.3
5.4
5.5
5.6
5.7
5.8
5.9
5.10
5.11
5.12
General
Location and Topography
Geology and Soil
Hydrogeology and Groundwater Quality
Climate
Ambient Air Quality
Ambient Noise
Flora and Fauna
Human Settlements
Land Use
Social Infrastructure and Public Services
Archaeological, Cultural and Recreational Resources
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C5-1
C5-1
C5-4
C5-5
C5-10
C5-14
C5-14
C5-14
C5-16
C5-17
C5-18
C5-19
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ENVIRONMENTAL IMPACTS
6.1
6.2
6.3
6.4
6.5
6.6
6.7
6.8
6.9
Methodology
Potential Environmental Hazards and Effects
Beneficial Impacts
Impacts on Natural Resources
Impacts on Air Environment
Impacts Water Environment
Impacts on Land Environment
Impacts on Ecology and Wildlife
Impact on Social Environment
C6-1
C6-1
C6-2
C6-3
C6-4
C6-5
C6-6
C6-7
C6-7
7
SUMMARY OF SIGNIFICANT EFFECTS AND MITIGATION MEASURES
C7-1
8
REFERENCES
C8-1
APPENDICES
1
Details of Personnel Responsible for Preparation and Review of the Report
2
Fuel Gas Analysis
3
Details of Stacks
4
PDO Environmental Risk Rating Criteria
5
Environmental Hazards and Effects Identification Matrix
A1-1
A2-1
A3-1
A4-1
A5-1
LIST OF TABLES
1.1
1.2
2.1
2.2
2.3
2.4
2.5
2.6
2.7
2.8
2.9
2.10
2.11
2.12
2.13
2.14
3.1
4.1
4.2
4.3
4.4
4.5
4.6
4.7
5.1
5.2
5.3
5.4
5.5
Description of Production Assets in PDO
Description of Service Assets in PDO
Environmental Laws and Regulations in Oman
Shell Group Environmental Specifications
PDO's Environmental Specifications
Air Emission Standards
Ambient Air Quality Standards
Classification of Standards A-1 and A-2 for Reuse of Treated Wastewater
Standards for Treated Wastewater Discharged on Land
Maximum Permissible Metal Concentrations in Sludge
Standards for Treated Wastewater Discharged into Marine Environment
Applicable Requirements for the Use of Energy, Materials and Resources
Classifications of Hazardous and Non-Hazardous Wastes
Ambient Noise Standards
Classification of Environmentally Sensitive Areas
Land Management Requirements
Consumption of Materials, Process Chemicals and Utilities by Gas Asset
Inventory of Stacks Under Gas Asset
Emission Loads from Stacks Under Gas Asset
Inventory of Emissions from Flares / Vents under Gas Asset
Air Emissions from Mobile Sources for Gas Asset
Solid Wastes Generated by Gas Asset Activities
Accidental Leaks and Spills Reported by Gas Asset
Accidental Leaks and Spills Reported by Infrastructure Asset
Physical Boundaries of Yibal and Qarn Alam Assets
Well Yield and Water Quality Data in Yibal and Qarn Alam Assets
Human Settlements in Yibal and Qarn Alam Asset Areas
Land Use in Yibal and Qarn Alam Assets
Environmentally Significant Areas in Yibal Asset
C1-1
C1-3
C2-1
C2-2
C2-3
C2-3
C2-4
C2-7
C2-7
C2-8
C2-9
C2-10
C2-10
C2-11
C2-12
C2-12
C3-11
C4-2
C4-3
C4-5
C4-6
C4-7
C4-8
C4-12
C5-1
C5-9
C5-16
C5-17
C5-19
LIST OF FIGURES
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1.1
1.2
3.1
3.2
3.3
3.4
3.5
3.6
5.1A
5.1B
5.2A
5.2B
5.3
5.4A
5.4B
5.5
Environmental Assessment:
2002 Review and Update
Geographical Map of PDO's Concession Area
Asset Organisation Structure in PDO
Asset Management Structure for Gas Asset
Process Flow Diagram of Governmental Gas Plant in Yibal
Process Flow Diagram of Governmental Butane Plant in Yibal
Process Flow Diagram of Central (Gas) Processing Plant in Saih Rawl
Process Flow Diagram of Gas Treatment Plant in Saih Nihayda
Process Flow Diagram of Gas Gathering Station in Barik
Topographical Map of Yibal Asset
Topographical Map of Qarn Alam Asset
Geographical Cross Section in Yibal Asset
Geographical Cross Section in Qarn Alam Asset
Soil Map of PDO’s Concession Area
Iso-salinity Map of Fars Aquifer
Iso-salinity Map of UeR Aquifer
Climatic Charts for Yibal - Qarn Alam Area
©HMR Environmental Engineering Consultants
Oman’s Environmental Consultancy
C1-2
C1-5
C3-2
C3-3
C3-5
C3-7
C3-9
C3-10
C5-2
C5-3
C5-5
C5-7
C5-8
C5-11
C5-12
C5-13
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ABBREVIATIONS
AP
API
bar(g)
bbl
bpd
Bq
atmospheric pressure (<0.5 kPa gauge pressure)
American Petroleum Institute
unit of gauge pressure (equal to 101.3 kPa gauge)
barrel (equal to about 159 liters)
barrels per day
Bequerel, unit for measurement of radioactivity (One nuclear
disintegration/second)
o
C
degree centigrade
o
K
degree Kelvin
CaCO3
calcium carbonate
CFC
chloro-fluoro-carbon
d
day
DGEA
Directorate General of Environmental Affairs
DLN
dry low NOx
DWD
deep water disposal
ESP
electrical submersible pump
E&P
exploration & production
EPC
engineering, procurement and construction
EU
European Union
h
hour
ha
hectare
HCFC
hydro-chloro-fluoro-carbon
HFC
hydro-fluoro-carbon
HEMP
hazards and effects management process
HMR Consultants HMR Environmental Engineering Consultants
HP
high pressure (>150 kPa gauge pressure)
kg
kilogram
km
kilometer
km2
square kilometer
kPa
kilo Pascal, unit of pressure (1 atm = 101.13 kPa)
LP
low pressure (0.5 – 150 kPa gauge pressure)
m3
cubic meter
mg
milligram
ml
milliliter
MLPS
main line pumping station
MOL
main oil line
MPN
most probable number
mPa.s
milli-Pascal-second (a unit of viscosity equivalent to 1 centipoise or cp)
MD
ministerial decision
MJ
mega-Joule
NOCS plant
North Oman crude stabilization plant
MW
megawatt
MWh
megawatt-hour
MRME&WR
Ministry of Regional Municipalities, Environment and Water Resources
MSDS
material safety data sheet
NAAQ
national ambient air quality
Nm3
normal cubic meter (at 1atm and 0 oC)
NO
nitric dioxide
NO2
nitrogen dioxide
NOx
oxides of nitrogen
NORM
naturally occurring radioactive materials
PDO
Petroleum Development Oman LLC
ppm
parts per million
ppmv
parts per million, volume based
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PM10
PM2.5
RD
RMS
RO
SHOC
Sm3
SOGL
STOIIP
t
TDS
tpa
tpd
tph
TSP
UeR
UNEP
UNESCO
USEPA
WHO
µg
µm
µS/cm
Environmental Assessment:
2002 Review and Update
particulate matter of <10 µm size
particulate matter of <2.5 µm size
royal decree
remote manifold station
reverse osmosis
safe handling of chemicals
standard cubic meter (at 1atm and 20oC)
south Oman gas line
stock tank of oil initially in place
metric tonne (equal to 1000 kg)
total dissolved solids
tonnes per annum (year)
tonnes per day
tonnes per hour
total suspended particulates
Umm er Radhuma
United Nations Environmental Program
United Nations Scientific and Cultural Organisation
United States Environmental Protection Agency
World Health Organisation
micro-gram
micro-meter (also known as micron)
micro-Siemens per centimeter (unit of electrical conductivity)
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1
INTRODUCTION
1.1
Petroleum Development Oman
Petroleum Development Oman (PDO) is the largest petroleum exploration and
production (E&P) company in the Sultanate of Oman, with over 113,550 km2 of
concession area, covering most of the central and southern parts of the Sultanate. The
geographical map of PDO’s concession area is shown in Figure 1.1. Presently, PDO's
concession area is divided into two main administrative assets viz., North Oman and
South Oman. The production assets within North Oman include Fahud, Lekhwair,
Yibal and Qarn Alam, and those within South Oman include Bahja, Nimr and
Marmul. The crude oil export facilities and the administrative head quarters are
located on the coast in Mina Al Fahal.
Currently PDO (including gas asset) operates from about a hundred fields and has
2,454 oil producing wells and 72 non-associated gas producing wells. The total
production of oil (black oil and condensate) currently is about 843,490 barrels per day
and that of gas (associated and non-associated) is about 44 million Sm3 per day as
reported for the year 2002. A network of 9,300 km of pipelines, 28 gathering stations
and 18 production stations feed the produced crude oil into the main storage facility
located at Mina Al Fahal near Muscat (at Muscat coastal area), from where the oil is
loaded into tankers moored offshore. The produced gas is partly utilised within the
assets and the rest processed in three gas stabilisation stations (located in Yibal, Saih
Rawl and Saih Nihayda) and then exported. The asset-wise break-up for land area,
crude oil production, gas production and production water is presented in Table 1.1
below for the current year (2002).
Table 1.1: Description of Production Assets in PDO
Production Asset
Fahud
Lekhwair Asset
Yibal Asset
(Including Gas Asset)
Qarn Alam Asset
Bahja Asset
Nimr Asset
(Including Rima and Al Noor)
Marmul Asset
Total for PDO’s Concession
Area
Land Area
(km2)
11,580
3,560
14,670
14,601
Gas
Production
(10 3 x Sm3/d
average)
5,007
1,550
5,830
18,900
30,560
31,134
14,462
12,347
31,995
3,084
550
154,970
67,255
27,050
16,160
26,960
113,550
35,669
11,221
134,104
780
900
43,866
313,105
41,937
637,533
©HMR Environmental Engineering Consultants
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Crude Oil
Production
(m3/d average)
Produced
Water
(m3/d average)
11,239
21,977
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Figure 1.1: Geographical Map of PDO’s Concession Area
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In addition to the seven production assets, there are service assets in PDO, which
provide technical, analytical, engineering, supply and transportation support to the
production assets. A brief description of the services assets is presented below in
Table 1.2.
Table 1.2: Description of Service Assets in PDO
Service Asset
GeoSolutions
Asset
Well Engineering
Asset
Infrastructure
Asset
Gas Asset
Main Activities and Areas of Operation
- Provide geo-services to frontier exploration and production assets for the
identification and development of hydrocarbon reserves within PDO’s
concession area
- The areas of technical service include seismic data acquisition & processing;
geological support & laboratory services; geomatics support; sub-surface
information management & technology support; exploration business
services; and reservoir characterisation.
- Prepare and update preliminary and detailed designs for new oil wells
throughout PDO’s concession area
- Prepare new oil well construction and completion programmes throughout
PDO’s concession area
- Construct new oil wells and modifying any existing wells as required
throughout PDO’s concession area
- Close out non-producing wells and restore abandoned well sites throughout
PDO’s concession area
TERMINAL OPERATIONS DEPARTMENT
- Operate and maintain the Mina Al Fahal Tank Farm consisting of 10 crude
oil storage tanks with a total storage capacity of 5 million barrels
- Operate and maintain the offshore oil export facilities in Mina Al Fahal
consisting of three single point moorings and two coastal buoy moorings
- Operate and maintain the oil export metering systems and offshore oil
pollution combating equipment in Mina Al Fahal
POWER SYSTEMS DEPARTMENT
- Operate and maintain ten power stations consisting of 22 gas turbines
throughout PDO’s concession area
- Operate and maintain twenty-two 132 kV substations throughout PDO’s
concession area
- Operate and maintain 1276 km long 132 kV overhead electrical transmission
lines throughout PDO’s concession area
PIPELINE DEPARTMENT
- Operate and maintain 1510 km long main oil line for transportation of liquid
hydrocarbons from all production assets to the export terminal in Mina Al
Fahal
- Operate and maintain 670 km long south Oman gas line for transportation of
dry sweet gas hydrocarbons from Saih Nihayda (Qarn Alam Asset) to
Marmul asset
- Operate and maintain the main oil line booster stations in Hubara (Nimr
Asset), Sahma (Bahja Asset) and Nahada (Fahud Asset)
- Operate and maintain, on behalf of the government, gas treatment facilities
(government gas plant, government butane plant and butane storage and
loading facility) in Yibal
- Operate and maintain, on behalf of the government, liquefied natural gas
upstream facilities in Saih Rawl, Barik and Saih Nihayda
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Logistics Asset
Estate Services
Asset
Production
Chemistry Asset
Environmental Assessment:
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Provide dedicated logistics support to all other assets in PDO through subcontracting for the following services:
- Cargo handling and haulage including rig moves
- Passenger commuting by land and air
- Fleet management
- Warehousing including central chemical storage
- Provide and maintain accommodation facilities for PDO staff in Mina Al
Fahal
- Maintain air-conditioning and refrigeration system within PDO area in Mina
Al Fahal
- Provide catering and laundry services for PDO staff in Mina Al Fahal
- Supply potable water and maintain electrical power distribution systems
within PDO area in Mina Al Fahal
- Manage sewage treatment plants, treated sewage re-use and solid waste
disposal for waste generated within PDO area in Mina Al Fahal
- Manage the incinerator located in mina Al Fahal for thermal destruction of
clinical wastes generated throughout PDO’s concession area
- Provide drilling chemistry support including analysis of drilling fluids and
cements, technical specifications for drilling fluids and cements, evaluation
of new drilling fluid and cement products and technologies for all assets in
PDO
- Provide process and treatment support including expert advice on all
chemical and physical processes related to production, treatment and
transportation of gas and oil for all assets in PDO
- Provide laboratory support for physico-chemical analysis of well fluids,
crude oil, gas, produced water, groundwater, treated water, sewage, raw
materials and process chemicals for all assets in PDO
The current asset organisation structure in PDO is shown in Figure 1.2.
1.2
Environmental Impact Assessment
The environmental impact assessment (EIA) for all the production and service assets
was first conducted during the period of 1998–2000, and based on this the
environmental management plans and programmes were developed. The previous
environmental assessment study for gas asset was completed in November 1999
(Reference 1). It is an internal requirement in PDO to review and update of the EIA
once in every three years, in order to periodically reassess the environmental impacts
and appropriately revise the environmental management plans and programmes.
Accordingly, PDO has retained HMR Environmental Engineering Consultants (HMR
Consultants) to carry out the first review and update of the EIA for all its assets.
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MANAGING
DIRECTOR
DEPUTY MANAGING
DIRECTOR
CHANGE
DIRECTOR
EXPLORATION
DIRECTOR
OIL DIRECTORS
(NORTH &
SOUTH)
TECHNICAL
SUPPORT
DIRECTOR
HSE MANAGER
(CSM)
PETROLEUM
ENGINEERING
MANAGERS
ENGINEERING
MANAGERS
OPERATIONS
MANAGERS
HEAD
ENVIRONMENTAL
AFFAIRS (CSM2)
HEAD OF HSE
HEAD OF
CONSTRUCTION
TEAM LEADERS
ENGINEERING
COORDINATOR
AREA
COORDINATOR
SUPERVISORS
SUPERVISORS
HSE
ADVISORS
ASSISTANT
HSE AVISOR
HR DIRECTOR
FINANCE
MANAGERS
FINANCE
DIRECTOR
HR MANAGERS
SOCIAL
INVEST.
MANAGER
OPERATORS/
TECHNICIANS
Figure 1.2: Asset Organisation Structure in PDO
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1.3
Environmental Assessment:
2002 Review and Update
Objectives and Scope of Study
The objectives of the present environmental assessment were the following:
-
Updating the environmental inventories in the asset, taking into consideration all
developments and activities that have taken place since the last environmental
assessment conducted in November 1999.
-
Reviewing the environmental requirements in the asset, taking into consideration
any recent changes in the legislative and corporate regulations and specifications
-
Auditing the environmental performance for the current year.
-
Updating the environmental baseline data, wherever required.
-
Reviewing the significant aspects and reassessing the environmental impacts, in
view of the above.
-
Revising the environmental mitigation and monitoring plan, wherever required.
The social and health impact assessment components were not included in the present
study. The quantitative risk analysis was also not included in the present study.
1.4
Method of Study
The present study was carried out in three stages. In the first stage, the previous EIA
reports (Reference 1) and other available environmental documents were reviewed.
Based on this review, detailed and structured checklists were prepared for asset data
verification and environmental performance audit. Subsequently, a site visit was
undertaken to check the ground realities and to collect all necessary information.
During the site visit, the key operating personnel in the asset including the Area
Coordinator and the Area HSE Advisor were interviewed, and detailed environmental
audit of the various facilities in the asset was conducted. In the third stage, all the data
collected were analysed and the significant environmental hazards (aspects) were
identified. Then the environmental effects (impacts) were reassessed using PDO’s
“Hazards and Effects Management Procedure (HEMP)” as described in the PDO's
document GU-195 "Environmental Assessment Guideline" (Reference 2). Following
the reassessment, the environmental mitigation and the monitoring plans were revised
as appropriate.
1.5
Structure of Report
This report is prepared based on the table of contents suggested for environmental
assessment report in PDO's "Environmental Assessment Guideline" (Reference 2). A
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non-technical executive summary is presented at the beginning of the report.
Following this introductory, the regulatory framework from environmental
assessment is presented in Section 2. The detailed description of activities performed
by gas asset is presented in Section 3. In Section 4, the wastes generated as a result of
these activities are discussed and their treatment and disposal practices are analysed.
A brief description of the current environment status of the areas within which the gas
asset operates is presented in Section 5. In Section 6, the significant environmental
hazards associated with the asset activities are identified and the environmental
effects are reassessed. The summary of significant effects and mitigation plan for
adverse impacts is presented in Section 7. The list of references is presented at the end
of the report under Section 8.
Other useful information not included in the main text is presented in the appendices.
The details of the personnel responsible in the preparation and review of the report are
presented in Appendix 1.
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2
REGULATORY FRAMEWORK
2.1
Omani Regulations
The Omani regulations on environmental protection, control and management are
covered under two basic laws viz., the “Law for the Conservation of the Environment
and Prevention of Pollution” first promulgated in 1982 as Royal Decree (RD) 10/82
and superseded in November 2001 as RD 114/2001 and the “Law on Protection of
Sources of Potable Water from Pollution” promulgated in November 2001 as RD
115/2001. The responsibility for the implementation of this law rests with the
Ministry of Regional Municipalities, Environment and Water Resources
(MRME&WR), which issues regulations, standards and guidelines through
“ministerial decisions (MDs)”. Within MRME&WR, the authority responsible for
environmental permitting, inspection and control in the Sultanate of Oman is the
Directorate General of Environmental Affairs (DGEA).
The current Omani environmental laws and regulations are listed below in
chronological order.
Table 2.1: Environmental Laws and Regulations in Oman
(Presented in Chronological Order)
Title
Protection of certain species of birds
Law on the development of water resources and its
amendments
Omani drinking water standards
Law on national heritage protection
Law for the conservation of the environment and prevention
of pollution and its amendments
Regulations concerning the disposal of liquid effluents to
marine environment
Regulations for the discharge of industrial and commercial
effluents
Regulations for septic tanks and holding tanks
Regulations for air pollution control from stationary sources
Regulations for the registrations of existing wells and new
well permits
Regulations for the management of the solid non-hazardous
wastes
Regulation for the management of hazardous wastes
Regulations for wastewater re-use and discharge
Regulating issuance of environmental permits
Regulation on the removal of vegetation
Regulation on hunting, capture or firing at wild animals
Regulations for noise pollution in public environment
Regulations for noise pollution in the working environment
Law on handling and use of chemicals
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Reference Number
MD 4/76
RD 76/77, RD 82/88, RD 29/00
OS8/98
RD 2/80, RD 6/80
RD 10/82 (superseded), RD 63/85,
MD 5/86, RD 71/89, MD 2/90, RD
31/93, RD 114/2001
MD 7/84
MD 8/84
MD 5/86 (superseded), MD 421/98
MD 5/86
MD 2/90
MD 17/93
MD 18/93
MD 145/93, RD 115/2001
MD 300/93
MD 128/93
MD 207/93
MD 79/94
MD 80/94
RD 46/95
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Title
Regulations for the handling of toxic substances
Regulations for control and management of radioactive
materials substances
Regulation on the use of desalination units on wells
Law on protection of potable water sources from pollution
2.2
Environmental Assessment
2002 Review and Update
Reference Number
MD 248/97
MD 249/97
MD 342/97
RD 115/2001
Shell Group Environmental Guidelines
The Royal Dutch Shell Group has a formulated an extensive HSE management
system covering all Shell’s activities including hydrocarbon exploration and
production. The system includes a series of comprehensive set of guidelines,
standards and procedures. These guidelines have been incorporated into PDO’s series
of specifications where applicable; yet remain as reference documents covering
specific operations and activities.
The Shells Group environmental specifications (standards and guidelines) are listed
below in Table 2.2.
Table 2.2: Shell Group Environmental Specifications
Reference Number
EP 95-0110
EP 95-0120
EP 95-0140
EP 95-0220
EP 95-0300
EP 95-0330
EP 95-0352
EP 95-0370
EP 95-0371
EP 95-0375
EP 95-0376
EP 95-0377
EP 95-0380
EP 95-0381
EP 95-0385
EP 95-0386
EP 95-0387
EP 95-0390
None
2.3
Title
Management of Contractor HSE
Competence Assurance for HSE-critical Activities
Exploration & Production HSE Strategy and Policy Implementation Guide
Concept Selection
Overview Hazards and Effects Management Process
Drinking Water Guidelines
Quantitative Risk Assessment
Environmental Assessment
Social Impact Assessment Guidelines
Environmental Quality Standards - Air
Monitoring Air Quality
Quantifying Atmospheric Emissions
Environmental Quality Standards - Water
Monitoring Water Quality
Environmental Quality Standards - Soil and Groundwater
Monitoring Soil and Groundwater
Contaminated Soil and Groundwater
Waste Management Guidelines
Guide for Risk Based Management of Potentially Contaminated Land
PDO Corporate Environmental Specifications
PDO has established a comprehensive health, safety and environment (HSE)
management system, based on ISO 14001, the international standard for
environmental management and EP: 95-0000, the Royal Dutch Shell group guidelines
on HSE management. PDO has developed environmental specifications for
application throughout its facilities within Oman, based on the Omani regulatory
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standards and Shell Group guidelines. PDO's specifications, which are described in
the following sections, fully comply with the Omani regulatory standards, and in most
cases are more stringent. The list of PDO's environmental specifications SP-1005 to
SP-1012 and SP-1170 version dated 7/2002 is presented below in Table 2.3.
Table 2.3: PDO's Environmental Specifications
Reference Number
SP-1005
SP-1006
SP-1007
SP-1008
SP-1009
SP-1010
SP-1011
SP-1012
SP-1170
Title
Specification for Emissions to Atmosphere
Specification for Aqueous Effluents
Specification for Accidental Releases to Land and Water
Specification for the Use of Energy, Materials and Resources
Specification for Waste Management
Specification for Environmental Noise and Vibration
Specification for Flora and Fauna Protection
Specification for Land Management
Specification for Management of Naturally Occurring Radioactive
Materials
In the following sections, the various environmental standards given under the above
specifications are summarized.
2.4
Environmental Standards
2.4.1
Emissions to Atmosphere
PDO specification SP-1005 on emissions to atmosphere addresses both stationary and
mobile sources and is largely based on MD 5/86 “Regulations for Air Pollution
Control from Stationary Sources” and Shell Exploration and Production International
best practices. These are presented below in Table 2.4.
Table 2.4: Air Emission Standards
Parameter
Hydrogen chloride
Hydrogen fluoride
Oxides of nitrogen (as NO2)
Phosphorus as (P2O5)
Hydrogen sulphide
Total particulates
Note: Nm3 refers to volume at 0 oC and 1atm.
Maximum Permissible Concentration
200 mg/Nm3
100 mg/Nm3
200 mg/Nm3
50 mg/Nm3
5 ppmv (7 mg/Nm3)
100 mg/Nm3
In addition to the above emission limits, PDO has specified the following
requirements to minimise air pollution and fugitive emissions:
(a) There shall be no continuous venting of gas in new projects.
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(b) Fugitive emissions occurring as a result of leaks from components (such as pipe
connections, valves, rotating shafts and other packed components) shall be
minimised through enhanced maintenance programs. There shall be no significant
visible emissions of fugitive dust.
(c) No smoke emitted shall be as dark or darker than shade 1 on the Ringlemann scale
(equivalent to 20% opacity).
(d) No odorous substances shall be emitted to the environment that are recognisable at
residences for more than 150 hours per year.
(e) CFCs, HCFCs or HFCs shall not be knowingly vented to the atmosphere. They
shall be recovered and re-used during servicing and maintenance. No equipment
or product containing CFCs shall be selected for purchase or lease. Further, no
equipment or product containing HCFCs shall be selected for purchase or lease,
unless no alternatives are available in the market.
(f) There shall be no halon releases to the atmosphere for maintenance, testing or any
other purposes. Halon releases are permitted under emergency situations only. No
new halon fire fighting systems in new projects shall be purchased, and no virgin
halons shall be used for recharging any existing halon fire fighting systems in use.
2.4.2
Ambient Air Quality
Presently, there are no Omani standards for ambient air quality. In their absence,
MRME&WR recommends the use of United States Environmental Protection
Agency's (USEPA) national ambient air quality (NAAQ) standards. PDO uses World
Health Organisation (WHO) - European Union (EU) and Netherlands standards,
which are more stringent than USEPA’s NAAQ standards. PDO’s ambient air quality
standards are given as both limit values and guide values. The “limit values” are the
maximum permissible concentrations in the ambient air, which if exceeded will result
in non-compliance. The “guide values” are the desirable upper limits. PDO's ambient
air quality standards are given in Table 2.5 below.
Table 2.5: Ambient Air Quality Standards
Parameter
Oxides of nitrogen as NO2
Sulphur dioxide
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Averaging
Period
1 hour
4 hour
24 hour
1 year
10 minutes
1 hour
24 hours
1 year
Limit Value
(µg/m3)
400
150
500
350
125
50
Guide Value
(µg/m3)
95
30
125
30
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Hydrogen sulphide
Carbon monoxide
Benzene
Total suspended particulate matter
Particulate products of incomplete combustion
2.4.3
Environmental Assessment
2002 Review and Update
30 minutes
24 hours
1 hour
8 hour
1 hour
1 year
1 year
24 hours
1 year
150
40000
6000
10
120
125
50
7
7.5
5
-
Aqueous Effluents
PDO specification SP-1006 on aqueous effluent discharge is derived from a number
of Ministerial Decisions (in particular, MD 7/84, MD 5/84 and MD145/93). The
effluents include production water and other various process waters, sewage and
storm water run-off. The specification covers both land and marine discharges. The
details are presented below.
•
Production Water:
The approved PDO Production Water Management Plan, which has been agreed upon
with the government consists of five principles. These principles govern the disposal
of production water (or other hyper saline brines), and are listed below in the order of
preference.
(a) Minimise the volumes of water produced during oil extraction.
(b) Maximise reuse of such produced waters.
(c) Phase out the use of shallow disposal wells and prevent disposal into useable or
exploitable aquifers.
(d) Return production water to the producing reservoir.
(e) Dispose surplus waters to formations, which have salinity greater than 35,000
mg/L, in conjunction with case-specific monitoring programs.
•
Other Process Effluents:
The disposal of other process (such as reverse osmosis plants, hydrotest, maintenance
etc.) effluents is dependent on the location and degree of the contamination. If the
effluent is to be discharged to land then the quality of the water shall satisfy the water
quality standards as identified in MD 145/93. Where the water is to be disposed of to
the marine environment the effluent shall meet the water quality standards as per MD
7/84. In the event that the water quality standards are not met then the effluent
discharge should be segregated and undergo treatment so as not to impact on the
receiving environment.
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Sewage Effluent:
PDO have developed a strategy to select the wastewater treatment technology for
various operations across the company. The strategy uses the population size of each
camp as a basis for selecting a wastewater treatment option. This approach is
summarised in the flowchart shown in below:
DOMESTIC WASTEWATER
MANAGEMENT STRATEGY
LESS THAN 150
PEOPLE
GREATER THAN 150
PEOPLE
SEPTIC TANK
PERMANENT STP
MOBILE STP
Effluent to be
discharged to a soak-away pit approved by
MRME&WR
Permit to discharge obtained
from MRME&WR stating
treatment capacity and
treatment standard
Effective for use
in temporary
camps or mobile
camps
Effluent from holding tanks
shall be removed by tanker
to a disposal location
approved by MRME&WR
Plant to be monitored
following daily and weekly
monitoring regime as stated
in Permit to Discharge
Permanent STP
Management to
be applied
Must be located 50 m from
any public water source or
falaj and at least 15 m from
any private well
Plant to be operated
according to operation to
meet the standards set in
MD145/93
•
Storm Water Runoff:
There are no legal requirements with respect to the discharge of storm water runoff
uncontaminated by hydrocarbons. Potentially hydrocarbon contaminated storm water
runoff shall be segregated and treated to the standards specified for on land discharge
or marine disposal.
•
On Land Discharge:
The following are PDO’s standards for on land discharge and re-use of treated
wastewater, which are the same as Omani standards (MD145/93 and RD 115/2001).
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There are two types of standards (Standard A-1 and A-2), which differ from each
other based on the intended re-use of treated sewage effluent. They are presented in
Table 2.6.
Table 2.6: Classification of Standards A-1 and A-2 for Re-use of Treated Wastewater
Specification
Crops
Standard A-1
- Vegetables likely to be eaten raw
- Fruit likely to be eaten raw and
within 2 weeks of any irrigation
Grass and
ornamental areas
-
Public parks, hotel lawns
recreational areas
Areas with public access.
Lakes with public contact (except
place which may be used for
praying and hand washing)
Standard A-2
- Vegetables to be cooked or
processed
- Fruit if no irrigation within 2
weeks of cropping
- Fodder, cereal and seed
crops
- Pastures
- Areas with no public access
The treated wastewater if discharged on land shall meet the following specifications
given In Table 2.7.
Table 2.7: Standards for Treated Wastewater Discharged on Land
Parameter
Biochemical oxygen demand
(5 days @ 200C)
Chemical oxygen demand
Suspended solids
Total dissolved solids
Electrical conductivity
Sodium absorption ratio
pH
Aluminium (as Al)
Arsenic (as As)
Barium (as Ba)
Beryllium (as Be)
Boron (as B)
Cadmium (as Cd)
Chloride (as Cl)
Chromium (total as Cr)
Cobalt (as Co)
Copper (as Cu)
Cyanide (total as CN)
Fluoride (as F)
Iron (total as Fe)
Lead (as Pb)
Lithium (as Li)
Magnesium (as Mg)
Manganese (as Mn)
Mercury (as Hg)
Molybdenum (as Mo)
Nickel (as Ni)
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Units
mg/L
Standard A-1
15
Standard A-2
20
mg/L
mg/L
mg/L
µS/cm
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
150
15
1500
2000
10
6-9
5
0.100
1
0.100
0.500
0.010
650
0.050
0.050
0.500
0.050
1
1
0.100
0.070
150
0.100
0.001
0.010
0.100
200
30
2000
2700
10
6 -9
5
0.100
2
0.300
1.000
0.010
650
0.050
0.050
1.000
0.100
2
5
0.200
0.070
150
0.500
0.001
0.050
0.100
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Parameter
Nitrogen: Ammoniacal (as N)
: Nitrate (as NO3)
: Organic ( Kjeldahl) (as N)
Oil and grease (total extractable)
Phenols (total)
Phosphorus (total as P)
Selenium (as Se)
Silver (as Ag)
Sodium (as Na)
Sulphate (as SO4)
Sulphide (total as S)
Vanadium (as V)
Zinc (as Zn)
Faecal coliform bacteria
Viable nematode ova
Environmental Assessment
2002 Review and Update
Units
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
Number
per 100 mL
Number
per L
Standard A-1
5
50
5
0.500
0.001
30
0.020
0.010
200
400
0.100
0.100
5
200
Standard A-2
10
50
10
0.500
0.002
30
0.020
0.010
300
400
0.100
0.100
5
1000
<1
<1
The sludge generated from the treatment of domestic wastewaters may be applied on
land for agricultural use, subject to the conditions set in Table 2.8. After spreading the
sludge, there must be at least a three-week period before any grazing or harvesting of
forage crops. Sludge application on land prohibited in the following cases:
-
On soils while fruits or vegetable crops, other than fruit trees, are growing or
being harvested
-
For six months preceding the harvesting of fruit or vegetables that are normally
eaten raw, and grown in contact with the soil
-
On soils with pH less than 7
Table 2.8: Maximum Permissible Metal Concentrations in Sludge
Metal
Cadmium
Chromium
Copper
Lead
Mercury
Molybdenum
Nickel
Selenium
Zinc
Maximum Permissible
Concentration
(mg/kg dry solid)
20
1000
1000
1000
10
20
300
50
3000
Maximum
Application Rate
(kg/ha/yr)
0.150
10
10
15
0.100
0.100
3
0.150
15
Maximum Permissible
Concentration in Soil
(mg/kg dry solid)
3
400
150
30
1
3
75
5
300
Any sludge containing metal concentration above the following prescribed limits shall
be disposed in sanitary landfills or to other facilities with approval from
MRME&WR.
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Marine Disposal:
Any effluent discharged into the marine environment shall meet the specifications
given below in Table 2.9, which are same as or more stringent than the discharge
limits into the marine environment as per MD 7/84.
Table 2.9: Standards for Treated Wastewater Discharged into Marine Enviro nment
Parameter
Arsenic
Cadmium
Chromium
Copper
Cyanide
Iron
Lead
Mercury
Nickel
Selenium
Silver
Zinc
Chlorine (salt)
Hydrogen ions
Sulfide salts
Sticking solid particles
Sludge
BOD
Oil & grease
Carbolic acids (phenols)
Ammonium nitrates
Phosphates
Faecal coliforms
Faecal streptococci
Salmonella
2.4.4
Discharge limit
0.05 mg/L
0.05 mg/L
0.50mg/L
0.50 mg/L
0.10 mg/L
2.00 mg/L
0.10 mg/L
0.001 mg/L
0.10 mg/L
0.02 mg/L
0.005 mg/L
0.10 mg/L
2.50 mg/L (minimum)
6-9 units
0.10 mg/L
30.0 mg/L
75.0 Jackson sight unit
30.0 mg/L
5.0 mg/L
0.10 mg/L
40.0 mg/L
0.10 mg/L
100 MPN/100 mL (80% samples)
100 MPN/100 mL
Zero MPN/L
Accidental Releases to Land and Water
PDO specification SP-1007 on accidental releases to land and water focuses on
minimising the effect on groundwater, and soil. The requirements are outlined below:
-
Equipment, processes, pipelines etc. containing material harmful to the
environment shall be designed, maintained, operated and abandoned to prevent
accidental releases to the environment
-
In case of a loss of containment to the environment, the contamination shall be
assessed and the soil and groundwater shall be cleaned to a level compatible with
the environmental quality standard of the receiving environment (available EP 950385)
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Environmental Assessment
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Use of Energy, Materials and Resources
PDO specification SP-1008 on the use of energy, materials and resources attempts on
the efficient use of natural resources. The requirements under this specification are
outlined in Table 2.10.
Table 2.10: Applicable Requirements for the Use of Energy, Materials and Resources
Indicators
Energy
Water Resources
Land Use
Use of Chemicals
2.4.6
Requirement
- Efficient use of energy at all times shall be demonstrated
- RD 82/88 controls the exploitation of groundwater in the interest of
agricultural and development plans
- MD 2/90 requires all wells used for the detection or extraction of
groundwater be registered with MRME&WR
- Efficient water use shall be demonstrated for hydrocarbon production
- Under PDO’s concession agreement, land no longer necessary for
operations shall be handed back to the government
- The manufacture, import, storage, handling and use of any chemical
substance shall comply with RD 46/95
- Under RD/248/97, the manufacture, export, transport, storage, handling
use, and disposal of any chemical substance will require a permit from
MRME&WR
- Chemicals shall only be bought with valid Safe Handling of chemicals
(SHOC) card. The chemicals shall be stored with the SHOC card visible
Waste Management
PDO specification SP-1009 on waste management defines what are hazardous and
non-hazardous wastes, and outlines the waste management strategy in PDO. This
specification complies with Omani regulations MD 17/93 and MD 18/93 dealing with
non-hazardous and hazardous waste management. The classification of non-hazardous
and hazardous wastes is specified under SP 1009 as below in Table 2.11.
Table 2.11: Classifications of Hazardous and Non-Hazardous Wastes
Hazardous Wastes
Hazardous empty drums
Waste lubricants
Pigging sludge
Tyres
Batteries
Clinical waste
Naturally occurring radioactive material
Sewage sludge
Oil-based drilling mud and cuttings
Hazardous waste chemicals and lab waste chemicals
Oily sand /soil
Oily sludge
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Non-Hazardous Wastes
Kitchen refuse
Domestic waste
Tree/grass cuttings
Water-based drilling mud and cuttings
Office waste
Non-hazardous waste chemicals
Non-hazardous empty drums
Scrap metal
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PDO’s waste management hierarchy is as below:
-
Pollution prevention: elimination, change or reduction of operating practices,
which result in wastes
-
Source reduction: generation of less wastes through more efficient processes
-
Re-use: the use of materials or products that are reusable in their original form
-
Recycling/recovery: the conversion of waste into usable materials, or the
extraction of energy or materials from the waste
-
Treatment: the destruction, detoxification and/or neutralisation of residues
-
Responsible disposal: depositing wastes using appropriate methods for a given
situation
Based on the above hierarchy, the detailed waste handling and disposal procedures are
given in the specification SP-1009. The procedures for the handling and disposal of
NORM wastes are given under the specification SP-1170. These are discussed in
Section 2.4.10 in this chapter.
2.4.7
Environmental Noise and Vibration
PDO specification SP-1010 on environmental noise and vibration is based on Omani
standards MD 79/94 and MD 80/94. PDO standards on ambient noise, which are the
same as Omani standards (MD 79/94) are summarized in Table 2.12 below.
Table 2.12: Ambient Noise Standards
Maximum Permissible Noise Level
[as Leq in dB (A)]
Type of District
Rural, residential, recreational
Suburban residential
Urban residential
Urban residential with some workshops
or business
Industrial and commercial
2.4.8
Workdays –
Day time
(7am –6pm)
Workdays –
Evening
(6pm –11pm)
45
50
55
40
45
50
Workdays
Night time
(11pm- 7am)
and Holidays
35
40
45
60
70
55
70
50
70
Flora and Fauna
PDO specification SP-1011 on protection of wildlife is developed in response to
several Omani royal decrees and ministerial decisions on environmental protection.
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The specification outlines specific ecological zones and based on their importance,
defines specific requirements for carrying out projects. These are summarized in
Table 2.13 below.
Table 2.13: Classification of Environmentally Sensitive Areas
Ecological Zone
Zone 1: Areas of
Concern
Zone 2: Areas of Interest
Arabian Oryx Sanctuary
2.4.9
Description
National reserves or sanctuaries
Areas that provide habitat to particularly
sensitive wildlife
Areas containing high proportions of
endemic flora or fauna
Woodlands
Areas of exceptional natural beauty
Areas having significant natural features
and beauty
Areas showing features of geological or
climatic history
Artificially created areas to attract
wildlife and migratory birds
Area defined by RD 9/94
Requirements
Activities shall be
restricted
Activities shall be
restricted for those not
compatible with the
protection of the area
Case-specific approval
from MRME&WR
Land Management
There is currently no specific Omani legislation on land management (site
preparation, abandonment and restoration). PDO’s policy on abandonment requires
that redundant assets shall be removed where appropriate and the environme nt
restored to, or as near as reasonably practicable, to its original state. PDO
specification SP-1012 on land management is summarized below in Table 2.14.
Table 2.14: Land Management Requirements
Project Stage
Site Selection
Site Preparation
Requirements
- Selection of a site shall be carried out in accordance with PDO’s
procedure on HEMP and environmental assessment guideline
- Earthmoving shall be conducted to minimize environmental effects
- Trees shall not be felled or removed
- Borrow pits shall not be excavated more than 2m in depth
- Borrow pits shall not be excavated in wadis, in areas used by grazing
livestock or in areas which would cause nuisance to local inhabitants
- A 20m wide right-of-way shall be provided for all pipelines (10m each
side)
- Where pipelines or roads cross wadis, earthmoving shall be carried out
to minimize flow or characteristics of shallow aquifers
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Site Abandonment
and Restoration
Environmental Assessment
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Requirements
- Restored land shall be visually similar to the surrounding landscape
- All waste materials shall be removed
- Hydrocarbon shall be removed from site if concentrations greater than
1% weight
- Areas having less than 1% weight hydrocarbon contamination shall be
covered with 0.6m of clean sand within 6 months of abandonment
- All pipelines, process equipment and instrumentation shall be removed
- All camp facilities shall be removed and site re-graded. Any soak pits
shall be backfilled
- Borrow pits shall be filled with 0.3m of clean sand and graded to match
the surrounding contours
2.4.10 NORM Waste Disposal
Oil sludges, pigging wastes, tubulars and water/well accessories from reservoir
locations are known to contain NORM materials. The monitoring, handling, transport,
storage, treatment and disposal of NORM wastes are specified under SP-1170
“Specification for Management of Naturally Occurring Radioactive Materials”. This
specification conforms to MD 249/97, “ Regulations for the Control and Management
of Radioactive Materials”. Any waste having radioactivity greater than 100 Bq/g (for
solids) and 100 kBq/L (for liquids) is classified as radioactive waste. Such waste shall
be sent to PDO’s dedicated storage facility in Zauliyah as soon as possible. Normal
transport vehicles can be used. However, the waste shall be packaged as per the
detailed procedures given in the specification. Any recyclable items shall be released
only after they are decontaminated by an authorised contractor at the designated site,
such that the radioactivity level is reduced to <100 Bq/g. If decontamination is not
possible, the wastes shall be retained at the storage site until the radioactivity level
drops to <100 Bq/g.
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3
ASSET DESCRIPTION
3.1
Introduction
Environmental Assessment:
2002 Review and Update
Gas asset is one of the eight technical service providers in PDO. While the other
service assets provide support services to customers within PDO (production assets
and other service assets), gas asset provides support services to an external customer,
viz., the government of the Sultanate of Oman, represented by Oman Gas Company
S.A.O.G. On behalf of the government, gas asset operates and maintains the following
gas handling and treatment facilities within PDO’s concession area:
-
Government gas plant located in Yibal
-
Government butane plant located in Yibal
-
Butane storage and loading facility located in Yibal
-
Central gas processing plant located in Saih Rawl
-
Gas treatment plant located in Saih Nihayda
-
Gas gathering station located in Barik
The other government gas facilities including natural gas pipeline system from Yibal
to Sohar, the various spur lines and pressure reducing terminals for natural gas
customers throughout Oman, which were previously under operation and maintenance
by gas asset are now under the full control of Oman Gas Company S.A.O.G.
Gas asset works under the overall direction of the Deputy Managing Director and at
asset level it is managed by the Gas Manager. The asset management structure
including the health, safety and environment (HSE) management structure is shown in
Figure 3.1.
The description of the various facilities operated and maintained by gas asset is
presented in the following sections.
3.2
Government Gas Plant
The government gas plant (GGP) is located in Yibal asset. GGP produces a low dew
point low pressure (LP) gas for export to consumers in the Sultanate. The feed to GGP
consists of raw gas from local gas wells, rich gas from the Yibal-A production station
and lean gas from Yibal and Lekhwair assets. The current production capacity of GGP
is 16.8 x 10 6 Sm3/day. The process flow diagram is shown in Figure 3.2. A brief
description of the process is presented below.
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GAS MANAGER
(GGM)
GAS
PLANNING
ENGINEER
(GGB)
ENGINEERING
MANAGER
(GGE)
HEAD OF
GOVT. GAS
FINANCE
SERVICE
(GGF)
HEAD OF GAS
OPERATIONS
(GGO)
HEAD OF GAS
PETROLEUM
ENGINEERING
(GGP)
GAS HSE
ADVISOR
(GGS)
Figure 3.1: Asset Management Structure for Gas Asset
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GLYCOL
REGENERATION
NONASSOCIATED
GAS
ASSOCIATED
GAS FROM
LEKHWAIR
AND YIBAL
INLET
SEPARATION
INLET
COMPRESSION
CONDENSATE
HANDING
FACILITY
GAS TREATMENT
TRAINS
GOVERNMENT
GAS USERS
CONDENSATE
TO YIBAL A AND
BUTANE PLANT
Figure 3.2: Process Flow Diagram of Governmental Gas Plant in Yibal
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The raw gas from gas wells is first passed through wellhead separators to remove bulk
entrainment and liquid slugs. This gas along with other feed gas is then passed
through filter separators to remove dirt and rust scales. The filtered gas is compressed
in six parallel compressors, driven by gas turbines. In the compressors, the low
boiling hydrocarbons are condensed out. Some condensate is sent to the government
butane plant for the recovery of butane and the rest of the condensate is returned to
the crude export line.
The compressed gas is passed through four parallel turbo-expander gas treatment
trains for water removal. The gas treatment trains are designed to achieve a water and
hydrocarbon dew point of -5°C and 1.5°C respectively. The gas in then further dried
in a glycol absorption unit, with glycol regenerated in a reboiler and recycled. Treated
gas is exported through the government gas pipeline.
3.3
Government Butane Plant
The government butane plant (GBP) is also located in Yibal asset. In the GBP, the
low boiling butane is recovered from the condensate generated in the GGP. The GBP
currently has a design capacity to produce 55 tonnes per day of commercial grade
butane. The process flow diagram is shown in Figure 3.3. A brief description of the
process is presented below.
The GBP consists of a de-ethaniser, a de-butaniser and an off-gas compression
system. In the GBP, the condensate first flows into the de-ethaniser feed drum
operating at a pressure of 3000 kPa. From there it flows into a water coalescer, where
free water is removed to below 100 ppm. The hydrocarbon liquid is then fed into the
top tray of the de-ethaniser column, which operates at a pressure of 2000 kPa. The
overhead vapour from the de-ethaniser is routed to the off-gas contactor, which
operates at a pressure of 1950 kPa. The bottom liquid from the de-ethaniser flows to
the de-butaniser column, which operates at a pressure of 1200 kPa. The overhead
vapour from the de-butaniser is condensed in an air-cooled condenser and is collected
in the de-butaniser overhead accumulator. The heating for columns is provided by a
hot oil system.
The condensed butane liquid is pumped to the storage and loading depot. Off-gas
from the de-ethaniser feed drum and the off-gas contactor is routed to the suction
scrubber. The scrubber operates at a pressure of 1900 kPa. Liquid from the scrubber
flows to the condensate line and the vapour is routed to the compressor.
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FALRE
OFF GAS
CONTACTER
DEETHANISER
GGP
CONDENSATE
YIBAL B. C
CONDENSATE
DEETHANISER
FEED DRUM
DEETHANISER
FEED WATER
COALESCER
BUTANE
LOADING
FACILITY
DEBUTANISER
CONDENSATE
TO YIBAL A
Figure 3.3: Process Flow Diagram of Governmental Butane Plant in Yibal
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3.4
Environmental Assessment:
2002 Review and Update
Butane Storage and Loading Facility
Butane produced from the GBP is stored in three butane storage vessels. Two vessels
are sized for 50 t capacity and the third for 100 t. High capacity loading pumps
transfer butane from the vessels to tankers via the loading arm. Displaced vapour from
the road tanker is returned to the storage vessel being discharged via the vapour return
arm of the loading arm. An odoriser unit injects an odorant into butane.
3.5
Central (Gas) Processing Plant
The central gas processing plant (CPP) is located in Saih Rawl. In the CPP, the gas
produced from the gas wells in the Barik field and the associated gas produced from
the oil wells in Saih Rawl field are stabilized. The CPP is designed for a total gas
processing capacity of 40 x 106 Sm3/day. The process flow diagram is shown in
Figure 3.4. A brief description of the process is presented below.
Barik gas and Saih Rawl well stream fluids are routed to four 3-phase production
separators, for primary separation of gas, free water and condensate. Gas from the
production separators is routed to two identical gas treatment trains and the
condensate to two identical condensate stabilisation trains. Water is disposed of by
export to the Saih Rawl Oil Station, where it is re-injected into the Shuaiba reservoir
for pressure maintenance purposes.
Gas from the production separators is pre-cooled with an air-cooler, to 60 oC and then
is dried in the glycol contactor. The dry gas exiting the glycol contactor is cooled in
exchanger and then further cooled in a turbo expander. Condensate from the cooled
gas is separated in low temperature separator and the gas is compressed in turbo
expander driven recompressor that boosts the gas pressure to approximately 79 bar(g).
Gas from both gas treatment trains is compressed to 90 bar(g) and export to the
natural gas plant at Sur.
Condensate from the gas treatment is fed to the condensate treatment train. The
condensate is cooled in an air-cooler to 60 0C, collected in a condensate flash vessel,
and fed to the stabilising column. The flash gas from the flash vessels, along with the
stabiliser off-gas, is recompressed and returned downstream of the gas treatment train
feed gas inlet air-cooler. The hot condensate bottoms product is cooled in the side
reboiler and further cooled in the condensate run-down air-cooler to 60 oC, before
being pumped to main oil line at Qarn Alam.
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RECOMPRESSOR
GAS
LNG PLANT
GAS
LOW TEMP
SEPARATOR
OIL
GAS
EXPANDER
GAS
GLYCOL
ABSORPTION
GAS
INLET
SCRUBBER
OIL
GAS
SAIH RAWL
GAS
BARIK GAS
GAS
3 PHASE
SEPARATOR
GAS
CONDENSATE
FLASH VESSELS
OIL
WATER
CONDENSATE
STABILISER
OIL
WATER
DEBUTANISER
LPG TO STORAGE
TO MAIN OIL LINE
DEGASSING
VESSEL
OIL TO SAIH RAWL
PRODUCTION STATION
WATER TO
DISPOSAL
Figure 3.4: Process Flow Diagram of Central (Gas) Processing Plant in Saih Rawl
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Part of the bottom condensate from the stabilization column is fed into de-butaniser
column. The de-butaniser is a refluxed column with a total condenser and operates at
a pressure of approximately 9 bar(g) and a bottoms temperature of some 238 oC. The
de-butaniser produces liquefied petroleum gas (LPG) from the overhead and
condensate from the bottom of the column. The condensate is pumped and
recombines with the main stabilized condensate. Finally, the condensate is air-cooled
to 60 oC before being pumped to Qarn Alam. LPG from the de-butaniser is air-cooled
to 60 oC and accumulates in a total condenser vessel. Liquid LPG from this vessel is
partly pumped to the LPG storage facilities and partly used as reflux for the debutaniser.
Electric power required in the plant is generated using six units of Frame 6 gas
turbine-generators. The heat for the reboilers is supplied by a hot-oil circulation
system that takes heat from waste-heat-recovery units installed on the gas-turbine
exhaust gases.
3.6
Saih Nihayda Gas Treatment Plant
A gas treatment plant is located in Saih Nihayda to treat the associated and nonassociated gas generated from Saih Nihayda and Saih Rawl fields. In this plant, the
condensates are removed from the feed gas and dry dew-pointed gas is produced. The
gas treatment plant is designed for a total capacity of 2.4 x 106 Sm3/day. Part of the
treated gas from the plant is fed into the South Oman gas line (SOGL) for export to
production assets in south for use as fuel gas. The rest is directly exported to Saih
Nihayda gathering station, Qarn Alam main production station, Ghaba North
gathering station and Qarat Al-Milh gathering station for use as fuel gas or lift gas.
The condensate recovered from the feed gas in the gas treatment plant is returned to
the crude oil system in Saih Nihayda gathering station. The process flow diagram is
shown in Figure 3.5. A brief description of the process is presented below.
The associated and non-associated gas from Saih Rawl and Saih Nihayda gathering
stations is fed through individual gas lines into free water knockout pots in the
treatment plant. The gas is split into two parallel streams, each feeding into a gas
treatment train. In the gas treatment train, the gas is first cooled with propane
refrigerant and then partially expanded. Glycol is added to the gas for dehydration,
which is separated from the condensate and regenerated. The resulting chilled gas will
be at about 6oC and 6900 kPa(g) pressure. The condensate from the free water
knockout pots and the gas treatment trains is stabilised, first in a high pressure vessel
and then in a low pressure vessel. The temperature in both vessels is maintained at
about 45oC using hot water.
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SOUTH OMAN GAS LINE
GHABA NORTH GATHERING STATION
SAIH NIHAYDA POWER PLANT
SAIH NIHAYDA GATHERING STATION
QARN ALAM MPS
UNASSOCIATED
GAS FROM SAIH
NIHAYDA FIELDS
ASSOCIATED
GAS FROM SAIH
RAWL STATION
GAS/GAS
HEAT
EXCHANGER
HYDROCARBON
KNOCKOUT POT
GAS CHILLER
GAS
FREE WATER OIL
KNOCK OUT
POT
CONDENSATE
ASSOCIATED GAS
FROM GHABA
NORTH STATION
FLARE
CONDENSATE
HANDLING
SYSTEM
SAIH NIHAYDA
GATHERING STATION
Figure 3.5: Process Flow Diagram of Gas Treatment Plant in Saih Nihayda
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The off-gas is routed to a flare. The stabilised condensate is returned to Saih Nihayda
gathering station, where it is mixed with the crude oil and exported to Qarn Alam
main gathering station.
3.7
Barik Gas Gathering Station
In Barik gas gathering station, the gas-rich well fluids produced from the various
wells located in Barik field are dehydrated and stabilised. The stabilized gas is sent to
Saih Rawl CPP for further processing. Barik gas gathering station is designed for a
total gas processing capacity of 16 x 10 6 Sm3/day. The process flow diagram is shown
in Figure 3.6. A brief description of the process is presented below.
GAS TO SAIH RAWL GAS STATION
GAS/GAS
HEAT
EXCHANGER
AIR COOLER
COLD
SEPARATOR
GAS
UNASSOCIATED
GAS FROM BARIK
FIELDS
INLET
SEPARATOR
CONDENSATE
LIQUID TO SAIH RAWL
WATER
WATER TO DISPOSAL
Figure 3.6: Process Flow Diagram of Gas Gathering Station in Barik
The well fluids are brought to the gathering station via flow lines. The fluids through
an inlet manifold enter two 3-phase separators. In the 3-phase separators, water and
condensates present in the well fluids are separated by gravity. The water separated
from the bottom of the separators is sent to the production water system in Al Ghubar
oil station for disposal. The condensates separated in the 3-phase separators are sent to
Saih Rawl main production station for further processing.
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The gas separated from the top of a 3-phase separators is further dehydrated in cold
separators. The cold separators operate at about 60 oC in summer and 40 oC in winter.
The inlet gas to the cold separators is first pre-cooled by the outlet (cold) gas and then
further cooled in an air-cooler. The outlet gas is heated in a line heater such that the
temperature of the gas when it arrives in Saih Rawl will be at least 5 oC above its
water dew point. The water separated in the cold separators is mixed with that
separated in the 3-phase separators and routed to the Al Ghubar oil station for
disposal.
3.8
Materials and Utilities
Gas asset is not a major consumer of materials and chemicals. The major materials
and chemicals consumed are lubricating oils and glycol. Lubricating oils are used in
the various pumps and rotary equipment. Fuel gas is consumed largely in the gas
turbines used for mechanical drive to the compressors in GGP. The hot oil heater used
in the GGP also consumes some fuel gas.
The current average consumption of utilities and materials in the gas asset is given in
Table 3.2 below.
Table 3.1: Consumption of Materials, Process Chemicals and Utilities by Gas Asset
Item
Purpose
Fuel gas (associated gas)
Used as fuel in gas turbines
(compressors) and hot oil
heater
Used for dehydration of gas
Used for lubricating pumps,
compressors, motors
Glycol
Lubricating oils
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Quantity Consumed
(Average for 2002)
153.33 x 10 3 Sm3/d
6 m3/month
1 m3/month
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4
RELEASES TO ENVIRONMENT
4.1
Introduction
Environmental Assessment:
2002 Review and Update
In this section, the various waste products and energies released into the environment
from the various activities performed by the gas asset are discussed. The activities
performed by the gas asset include the following:
-
Operation and maintenance of government gas plant located in Yibal
-
Operation and maintenance of government butane plant located in Yibal
-
Operation and maintenance of butane storage and loading facility located in Yibal
-
Operation and maintenance of central gas processing plant located in Saih Rawl
-
Operation and maintenance of gas treatment plant located in Saih Nihayda
-
Operation and maintenance of gas gathering station located in Barik
The wastes released into the environment from all the activities discussed above may
be classified into the following groups, based on their physical state as well as nature:
-
Air emissions
-
Liquid effluents
-
Solid wastes
-
Noise
-
Accidental leaks and spills
In order to quantify and characterize these releases, the currently available database is
used. In cases where data are not available or insufficient, an attempt is made to
estimate the quantities and characteristics using theoretical or empirical equations.
Where estimates based on theoretical or empirical equations are considered not
reasonably accurate, recommendations are made for direct measurement.
4.2
Air Emissions
4.2.1
Overview
The air emissions in the asset for the purpose of this report are classified into the
following categories:
-
Stack emissions
-
Flare / Vent emissions
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-
Fugitive emissions
-
Mobile source emissions
Environmental Assessment:
2002 Review and Update
The discussion on the emission sources, quantities, characteristics and emission
controls is presented in the following sections.
4.2.2
Stack Emissions
Stack emissions are the most dominant air emissions in gas asset by virtue of their the
quantity. The main sources of stack emissions are the gas turbines in which fuel gas is
burned to generate mechanical drive of the compressors used in the asset. In addition,
some emissions are also released from the stack attached to the hot oil heater in the
GGP. There are also some standby diesel generators used for emergency power
supply. The emissions from standby diesel generators are very infrequent and hence
of no significance. Hence, they are not considered further in this report.
The inventory of stacks under the operational control of gas asset is presented below
in Table 4.1.
Table 4.1: Inventory of Stacks Under Gas Asset
Location
Government gas plant in Yibal
Government butane plant in Yibal
Butane storage and loading facility in Yibal
Central processing plant in Saih Rawl
Gas treatment plant in Saih Nihayda
Gathering station in Barik
Asset Total
Gas Turbine
Stacks
Heater
Stacks
Total Number
of Stacks
6
0
0
0
0
0
6
1
0
0
0
0
0
1
7
0
0
0
0
0
7
The fuel burned in all the above systems is the associated gas produced in the asset.
The detailed analysis of the fuel gas used in the asset is shown in Appendix 2. The
emissions are the products of combustion. The pollutants of concern in these
emissions are oxides of nitrogen (NO X), carbon monoxide (CO) and particulate matter
(PM), which is primarily due to unburnt hydrocarbons (HC) that are released as fine
particulates of <10µm size (PM10) with a significant fraction under 2.5µm size
(PM2.5). Further, the emissions also contain significant quantity of carbon dioxide
(CO2), which is a greenhouse gas. Sulphur dioxide (SO 2) emissions are of no concern,
since the fuel gas used is virtually sulphur free.
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Detailed information on the stack design specifications, exit temperature, exit
velocity, total gas flow rate, heat emission rate and the emission rates of individual
pollutants for each stack is not currently available. The stack emissions are not
regularly monitored. In PDO, stack emissions are estimated based on Tier 3 emission
factors given in the Shell group specification EP 95-0377 on “Quantifying
Atmospheric Emissions” (Reference 3). The emission factors for gas turbines used in
PDO are as given in below :
CO2
CO
NOx as NO 2
SO2
HC
: 2750 kg per tonne of gas burned
: 2.7 kg per tonne of gas burned
: 6.7 kg per tonne of gas burned
: 20 x S kg per tonne of gas burned
: 0.47 kg per tonne of gas burned
where S is the mass% of sulphur in the fuel gas.
The emission inventories for all the assets are summarized in Table 4.2 below.
Table 4.2: Emission Loads from Stacks Under Gas Asset
Location
Government gas plant in
Yibal
Government butane
plant in Yibal
Butane storage and
loading facility in Yibal
Central processing plant
in Saih Rawl
Gas treatment plant in
Saih Nihayda
Gathering station in
Barik
All locations
Quantity of Emissions
CO
SO2
NOX as
(tpd)
(tpd)
NO2
(tpd)
Fuel
Consumed
in 1000
Sm3/d
CO2
(tpd)
153.33
465.26
0
1.08
0.44
0.08
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
153.33
0
465.26
0
0
0
1.08
0
0.44
0
0.08
HC
(tpd)
Particulate emission controls are required only for fuels such as solid fuels and heavy
petroleum residues with significant ash content. Particulate emissions (due to unburnt
HC) from the stacks are not significant. The HC emissions along with CO emissions
are minimised due to high combustion efficiency. SO 2 emissions are dependent on the
sulphur content (or H2S concentration) in the fuel gas. The gas used in the power
plants and booster stations is the dry sweet gas with H2S concentration is negligible.
Hence SO2 emissions will not be significant.
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NOx emissions from standard combustion systems in the gas turbines can be quite
significant. While there are no Omani specifications presently, PDO specification SP1005 requires that NO x emission concentration shall not exceed 200 mg/Nm3. No data
are available on NO x concentrations in the stack emissions and no NO x emission
control systems are provided for any of the existing combustion systems.
4.2.3
Flare / Vent Emissions
Flares and vents are provided in the asset to release into the atmosphere any
associated gas that cannot be utilised or re-injected into the reservoir. PDO has a “no
continuous venting” policy, which requires that gases are flared (combusted at the
flare tip) such that no unburned hydrocarbons are released into the atmosphere.
Venting is permitted only under abnormal conditions such as insufficient gas pressure
or quantity to support the flame. In PDO’s terminology, vent is an unlit (cold) flare
and as such, there is no physical difference between a vent and a flare. Three types of
flares / vents exist in PDO, viz., high pressure (HP) flare / vent, low pressure (LP)
flare / vent and atmospheric pressure (AP) flare / vent. The principal difference is that
the gas pressure is greater than 150 kPa(g) for HP flare / vent, 0.5 to 150 kPa(g) for
LP flare / vent and 0 to 0.5kPa(g)for AP flare / vent.
The constituents in the flare emissions are no different from those of stacks, except
for their composition. Generally, the emission factors (tonnes emission per tonne of
gas flared) for CO and HC from the flares are substantially higher than those for
stacks. The emission factors for flares are estimated in PDO based on Tier 3 emission
factors (Reference 3), as given below:
CO2
CO
NOx as NO 2
SO2
HC
Smoke index
: 27.5 x E kg per tonne of gas flared
: 8.7 kg per tonne of gas flared
: 1.5 kg per tonne of gas flared
: 20 x S kg per tonne of gas flared
: 3 x (100 - E) kg per tonne of gas flared
: Ringlemann 1
where E is the flare efficiency (assumed to be 95%) as percentage and S is the mass
percentage of sulphur in the fuel gas. In the case where the flare is unlit (cold vent),
the emissions have the characteristics as the vented gas.
The concentrations of pollutants, mainly HC, CO and NO x in the flare emissions are
controlled by proper design of the flare tip. The basic principle is to ensure near
complete combustion through good entrainment of air for combustion, good fuel-air
mixing and flame stability. All the flares are currently designed such that the smoke
index, which a measure of combustion efficiency is Ringlemann 1 or lower.
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The details of flares / vents in the asset are presented below in Table 4.3.
Table 4.3: Inventory of Emissions from Flares / Vents under Gas Asset
Area
Government gas plant in
Yibal
Government butane plant
in Yibal
Butane storage and loading
facility in Yibal
Central processing plant in
Saih Rawl
Gas treatment plant in Saih
Nihayda
Gathering station in Barik
Asset total
4.2.4
Number of
Flares / Vents
Quantity of Gas
Flared / Vented
(10 3 Sm3/d)
No. of Hours
Vented per
Year
CO2 Emission
Rate
(tpd)
2
(2 LP)
0
11.95
0
34.33
0
0
0
0
0
0
0
4
(2 LP +2 AP)
1
(1 LP)
1
(1 LP)
8
(6 LP +2 AP)
169.94
0
665.96
6.27
0
24.57
Included in CPP
0
-
188.16
0
724.86
Fugitive Emissions
Fugitive emissions of hydrocarbons are expected from the gas processing and
handling facilities in the asset. Currently, no estimates are available for such fugitive
emissions. Further, no leak detection and repair systems are available in the facilities.
While it is unlikely that mass rates of fugitive emissions are significant, their potential
for adversely affecting the workplace and near-field ambient air quality cannot be
discounted under certain conditions.
4.2.5
Mobile Source Emissions
Road vehicles used by the asset personnel for the transportation of materials and men
within their areas of operation constitute the mobile air emission sources. The
significant pollutants present in these emissions are NO x, CO and unburnt HC. The
emission factors (mass of pollutants emitted per running kilometre) depend on the
type of the motor vehicle, type of the fuel, running speed, load conditions and
environmental conditions. In PDO, the air emissions from mobile sources are
estimated based on Tier 3 emission factors (Reference 3). For the sake of simplicity,
PDO uses common emission factors for all categories of land transport vehicles as
shown below:
CO2
CO
NOx as NO 2
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27 kg per tonne of fuel
38 kg per tonne of fuel
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HC
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8 kg per tonne of fuel
5.6 kg per tonne of fuel
In the above estimates, it is assumed that all vehicles are diesel driven, moderately
aged and the sulphur content in the fuel is 0.4% by mass.
The estimated total emissions from mobile sources in the asset are as given in Table
4.4 below.
Table 4.4: Air Emissions from Mobile Sources for Gas Asset
Parameter
Total quantity of fuel consumed – petrol / diesel*
Total emission of CO2
Total emission of CO
Total emission of NOx
Total emission of SO2
Total emission of HC
Quantity
(Jan- Dec 2002)
2571.0
8227.3
69.4
97.7
14.4
65.8
* Total km by all vehicles for Gas asset for the year 2002 is 432104 km and assuming average mileage of 7km/litre of fuel.
4.3
Liquid Effluents
No continuous liquid effluents are discharged by gas asset. The associated water
(produced water) separated from the well fluids in the gas asset facilities is sent to
other production facilities in PDO for treatment and disposal. The details treatment
and disposal of produced water and its environmental impact are discussed in the EIA
report of the production assets. Therefore, they are not considered in this report.
Similarly, any effluents, such as hydrotest water generated during the laying of new
gas pipelines are also not considered in this report. Laying of any new pipelines for
gas transport is considered as a major project, which requires a separate EIA study
Therefore, any additional effluents that may generated due to any new project
activities will be considered in a separate EIA report.
Accidental spills and leaks of liquids such as fuel oils, chemicals and water may
occur. Such accidental releases are discussed separately in Section 4.6.
4.4
Solid Wastes
In PDO, the solid wastes are classified into broad categories as non-hazardous and
hazardous. The sub-groups in each category are as below:
Non-hazardous wastes: domestic and office waste; water based drilling mud and
cuttings; non-hazardous industrial waste
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Hazardous wastes: oil based mud and cuttings; sewage sludge; waste lubricants; oily
sludges; oily sand; pigging sludge; non-recyclable batteries; recyclable hazardous
batteries; transformers and transformer cooling fluids; clinical wastes; NORM wastes;
chemical wastes (including miscellaneous hazardous wastes)
From the activities performed in gas asset, only a few types of wastes are generated.
Their sources of generation, quantities and methods of disposal are shown in
Table 4.5.
Table 4.5: Solid Wastes Generated by Gas Asset Activities
Waste Type
Source of
Generation
Pigging waste
Gas pipeline
cleaning
Mercury waste
Gas treatment
Waste lubricant oils
Gas
compressors
and motors
4.5
Quantity
Generated per
Year
Unknown
Method of Disposal
Sent to the nearest PDO Waste
Management Centre in PDO for
landfilling
Unknown Presently no waste management
facility.
1.8-2.0 m3/month Sent to the nearest PDO Production
Station or Waste Management
Centre for storage in the oil saver
pit for recycling
Noise
Both continuous and intermittent sources of noise are present in the areas under the
operational control of gas asset. The major noise generating sources are the
compressors in GGP, which generate continuous high level noise. The other
continuous noise sources include rotary pumps, electrical motors, burners, stacks,
flares and other rotating equipment. All these sources are outdoor, stationary point
sources. The intermittent sources include the pressure relief valves, standby diesel
generators and some intermittently operated pumps and motors.
The mobile sources include the road transportation vehicles such as cars, vans, buses
and trucks used by the gas asset staff and contractor staff.
Due to the presence of a large number of noise generating sources in process areas
(turbines in the gas compressor area), it is not possible to measure the noise level at
the source point for each equipment. Therefore, instead of considering all the
individual sources as distinct point sources, a group of them may be treated as an area
source. Currently, no data are available on the noise levels for either point sources or
area sources. It is however noticed during the site visits that at several places the noise
levels are greater than 85 dB(A), which is the permissible workplace noise level. No
information is available on noise levels for mobile sources.
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All the major noise generating equipment such as pumps, motors, compressors,
burners etc. are provided with standard noise control systems such sound insulation,
vibration control and acoustic packages where necessary.
4.6
Accidental Leaks and Spills
In PDO, all accidental leaks and spills shall be promptly reported. There are three
categories of accidental leaks and spills, as below:
-
Oil leaks and spills
Chemical leaks and spills
Water leaks and spills
Release of ozone depleting substances (ODS)
The potential sources of oil leaks and spills for gas asset are condensate lines and
rotating equipment. The use of chemicals is very limited in gas asset activities. Water
leaks and spills, though do not lead to any environmental consequences, are reported
in PDO as a matter of water conservation issue. ODS include CFCs, halons, HFCs
and HCFCs. The use of these substances is currently phased out in PDO due to their
high ozone depletion potential. Some inventories of such substances may still be
found in some air-conditioners and portable fire extinguishers. According to PDO’s
specification SP-1005, these substances are not permitted to be released into the
atmosphere except in uncontrollable situations or emergencies.
For the current year (2002), the leaks and spills reported by gas asset are summarized
in Table 4.6.
Table 4.6: Accidental Leaks and Spills Reported by Gas Asset
Description
Oil Leaks
and Spills
Total number of incidents
Number of spills into wadis
Total volume leaked / spilled
Total land area impacted
Total quantity of soil contaminated
©HMR Environmental Engineering Consultants
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1
0
30 m3
-
Jan – Dec 2002
Chemical
Water
Leaks and
Leaks and
Spills
Spills
0
0
0
0
0
0
0
0
0
0
Releases of
ODS
(CFCs and
Halons)
0
-
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5
ENVIRONMENTAL SETTING
5.1
General
In this chapter, the existing environment in the areas operated by gas asset is
described and analysed. The description is largely based on the information provided
in the previous EIA report (Reference 1). Additional information is sourced from site
reconnaissance surveys conducted as apart of the present environmental assessment
study (refer Section 1.3). For those environmental aspects subjected to very little
change since the last environmental assessment due to the activities in the asset, only
brief description and analysis have presented in this chapter. Detailed description and
analysis are limited to the environment aspects that are likely to have undergone a
noticeable change since the last environmental assessment. The areas where specific
data are required but not available are identified.
The environmental aspects likely to have undergone noticeable change due to the
asset activities include the following:
-
Groundwater resources and groundwater quality
-
Ambient air quality and noise
-
Land use and human settlements
5.2
Location and Topography
The facilities operated and maintained by gas asset are located in Yibal, Saih Rawl,
Saih Nihayda and Barik. While Yibal is located within Yibal asset area, Saih Rawl,
Saih Nihayda and Barik are located within Qarn Alam asset area. The physical
boundaries of Yibal and Qarn Alam assets are given in Table 5.1 below:
Table 5.1: Physical Boundaries of Yibal and Qarn Alam Assets
Site Boundaries
Northern limit
Eastern limit
Southern limit
Western limit
Clarke 1880 System (Easting or Northing (m))
Yibal Asset
Qarn Alam Asset
2471406 N
2420800 N
441344 E
577686 E
2387025 N
2303586 N
339593 E
361961 E
The topographical maps of Yibal and Qarn Alam assets are shown in Figures 5.1A
and Figure 5.1B.
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Figure 5.1A: Topographical Map of Yibal Asset
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Figure 5.1B: Topographical Map of Qarn Alam Asset
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•
Environmental Assessment:
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Topography of Yibal Asset
The northern half of the Yibal area is composed of flat featureless gravel plains and
low gravel hills with a few rocky outcrops. Low un-stabilized sand dunes and shallow
wadis are also present. The southern part of the asset is a part of a large sabkha called
the Umm as Samim. The two main wadis are Wadi Aswad and Wadi Yibal. These
wadis flow southwest from the Hajar mountains and drain into the depression of
Umm as Samim. There is some evidence of surface and subsurface water flow in the
wadis. Flow in Wadi Aswad ceases at about 40 km from Umm as Samim and the flow
of Wadi Umayri extends to about 10 km from Umm as Samim.
•
Topography of Qarn Alam Asset
The topography and landscape of most of the asset area is very similar to many other
areas of central Oman, characterised by flat plains interspersed with small drainage
channels and occasional rocky outcrops.. Most of the Qarn Alam Asset area lies in the
plains south of the foothills of the northern Hajarmountains and consists of alluvial
gravel fans arising from a number of wadis. One of the major wadis is Wadi Umayri,
which drains into the Umm as Samim sabkha in the north west of the Asset. Other
smaller wadis include Wadi Majhul, Halibah, Thaylah and Wadi Qitfah.
5.3
Geology and Soil
Yibal asset area is composed of alluvial gravel and aeolian sand, underlain by chalk
and marl. The underlying rock is almost horizontal mid-tertiary limestone from the
Oligocene and Miocene era. The tertiary formations are about 700 m thick and lie on
the top of oil bearing Shuaiba formation. The water bearing tertiary formations
consists of Fars, Dammam, Rus and Umm er Raduma (UeR) formations. The
geological cross section of the asset is shown in Figure 5.2A.
The geological sequence of Umm as Samim sabkha deposit is halite-bearing sands,
halite and halite-bearing sands from bottom to top. The sabkha deposits consist of a
main zone of salt crust, including heaved crust. Brine is present very close to the
surface. Fresh salt is constantly deposited as a result of evaporation. The crust
accumulates wind blown dust, gradually darkens and often rises to a height of 0.5 m.
Towards the Rub al Khali, soft fine grained sands are saturated with brine 1-1.5 m
below ground level.
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Figure 5.2A: Geographical Cross Section in Yibal Asset
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Most of the exposed surface formations in Qarn Alam asset are tertiary deposits. The
shallowest formation belongs to the Fars group comprising carbonates and clastics.
The deposits are mainly evaporatic in nature. The thickness of the Fars group in this
area varies from approximately 30 to 100 m with the thickness increasing from Qarn
Alam towards Musallim. The UER group consists of a thick assemblage of
carbonates. The Shammar shale, belonging to the Aruma group, underlies the Umm
Er Radhuma and is regarded as an aquitard. The thickness of Shammar shales is
appreciable, ranging from 100 to 150 m in the Saih Rawl and Musallim areas. In the
Qarn Alam area, however, the thickness of the Shammar shale is less than 20 m. The
Wasi Kahmah and Sahtan groups belong to the Cretaceous and Jurassic period. They
contain marine carbonates. The Akhdar group contain carbonates belonging to the
Permian Triassic age and underlie the Sahtan group. The Haushi group, underlying
the Akhdar group contains sediments, which are glacial, shallow marine siliciclastics.
This group contains the hydrocarbon bearing Gharif and Al Aklata formation. The
Haima group consists of clastic sediments and they are the deepest known aquifers.
The oldest known sequence is the Huqf group consisting of siliciclastics, carbonates
and thick evaporites. The geological cross section in the asset is shown in Figure
5.2B.
No site-specific data are available on the soil quality. Generally, the soils in the asset
are classified as unsuitable for agricultural purposes, as per the Ministry of
Agriculture and Fisheries “General Soil Map of Oman". The general soil map of
Oman is shown in Figure 5.3.
5.4
Hydrogeology and Groundwater Quality
The aquifer system in Yibal and Qarn asset areas is composed of Fars, Dammam, Rus
and UeR formations. UeR formation forms the principal aquifer system, which is
artesian, and covers a wide area of the eastern Arabian peninsula. Overlying it, and
sometimes in hydraulic connection with it, is the Rus formation. Where it is
unconnected, this is an aquifer system of little importance and is characterised by high
sulphate levels derived from its evaporitic lithology. Also of little importance is the
Damman aquifer, which is of limited thickness and extent and characterised by highly
saline water.
The Fars Group formation is of greater importance, offering a shallow source of
water, usually of superior quality than anything available at greater depths. Upward
seepage from Tertiary limestones is significant in the Umm as Samim, resulting in the
formation of brines. Groundwater quality remains generally low in Yibal asset area,
with salinity levels rarely below 20,000 mg/L.
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Figure 5.2B: Geographical Cross Section in Qarn Alam Asset
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Figure 5.3: Soil Map of PDO’s Concession Area
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In Qarn Alam asset areas, the water in Fars formation is saline with a TDS ranging
from 15000 to 48000 mg/l. Water wells in this formation have a yield of 700 to 1200
m3/d. The water table is at 76 m below ground level in Saih Rawl water disposal well.
The yield of wells in the UeR varies from 800 to 2600 m3/d. Water quality in this
aquifer is typically in the range of 30,000 to 120,000 mg/l TDS).
The iso-salinity maps of Fars water and UeR water are given in Figure 5.4A and
Figure 5.4B respectively.
The well yield and water quality data for different locations within Yibal and Qarn
Alam asset are summarised below in Table 5.2. The change in water level and water
quality over the past few years has also been shown.
Table 5.2: Well Yield and Water Quality Data in Yibal and Qarn Alam Assets
Location
Representative
water well
Aquifer
Water level in m
TDS in g/L
Yield in m3/h
AL HUWAISAH
AL HUWAISAH
WSW-14
Rus+UeR
3.83/Jul’93
2.27/Jul’96
20.162/Sep’88
-
AL HUWAISAH
AL HUWAISAH
WSW-4
Fars+
Dammam
-
15.466/Mar’81
14.563/Apr’94
-
AL HUWAISAH
AL HUWAISAH
WSW-5
UeR
-
79.176/Mar’82
65.909/Dec’92
-
AL HUWAISAH
AL HUWAISAH
WSW-6
Rus
9.95/Mar’87
1.65/Jul’97
22.392/Feb’83
15.123/Apr’94
-
AL HUWAISAH
AL HUWAISAH
WSW-12
Dammam+
Rus
-
40.675/Jun’88
54.476/Apr’94
-
YIBAL
YIBAL WSW-1
UeR
-
72.001/Jul’80
58.783/Jul’89
-
YIBAL
YIBAL WSW-8
Fars+
Dammam
14.9/Mar’81
27.0/Nov’96
14.134/Jul’80
14.21/Jul’89
22.55/Mar’81
26.5/Nov’96
AL GHUBAR
AL GHUBAR
WSW-4
Fiqa+Natih
74.95/Jan’88
73.92/Mar’96
40.78/Nov’94
-
ALAM
ALAM WSW-4
Fars+UeR
47.92/Sep’89
57.41/May’99
36.541/Jul’88
-
BARIK
BARIK NORTH
WSW-1
Taqa+Rus
59.27/Jan’87
59.08/Jan’97
54.007/Dec’85
73.119/Oct’91
BURHAAN
BURHAAN WSW-1
UeR
9.9/Feb’91
17.53/Jan’01
14.556/Jan’88
16.857/Aug’91
20.0/Dec’00
BURHAAN
BURHAAN WSW-2
Fars+UeR+
Arada
11.86/May’88
13.54/May’99
29.225/Jul’91
18.0/Nov’00
GHABA
NORTH
GHABA NORTH
WSW-2
UeR
51.3/Apr’87
48.71/Mar’96
17.239/Aug’80
16.295/May’89
-
HABUR
HABUR WSW-1
UeR
26.3/May’89
25.44/May’99
121.827/Feb’83
-
MABROUK
MABROUK WSW-3
Dammam
36.05/Feb’97
35.61/May’99
118.149/Feb’97
28.0/Feb’97
MUSALLIM
MUSALLIM WSW1
MUSALLIM WSW5
Rus+UeR
-
44.887/Nov’81
-
-
10.84/Oct’00
-
66.0/Oct’00
QARAT AL
MILH
QARAT AL MILH
WSW-2
Quaternary+
UeR+Fiqa
7.25/Apr’87
6.95/Jun’97
36.702/Aug’85
-
QARN ALAM
QARN ALAM
WSW-3
UeR
35.82/Nov’89
28.76/Nov’00
97.717/Mar’82
19.727/Apr’94
-
MUSALLIM
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RAMLAT
RAWL
RAMLAT RAWL
WSW-1
Fars+UeR
SAIH
NIHAYDA
SAIH NIHAYDA
WSW-1
Fars+UeR
SAIH
NIHAYDA
SAIH NIHAYDA
WSW-2
UeR
SAIH RAWL
SAIH RAWL WSW4
Rus+UeR
57.0/Jun’90
58.37/Jun’99
60.77/Aug’88
52.12/May’99
24.174/Nov’80
97.916/Oct’89
41.414/May’81
55.443/Mar’82
-
60.12/Jun’90
56.65/May’99
55.89/Oct’94
39.58/Oct’02
31.568/May’81
36.243/Aug’86
74.805/May’77
-
-
-
“-“ means data not available
5.5
Climate
Meteorological data are not recorded in Yibal or Qarn Alam assets. The nearest
location where meteorological data are available is Fahud. Fahud is about 50 km to
the east of Yibal and about 120 km to the southwest of Qarn Alam. The climatic
conditions in Yibal and Fahud assets are more or less similar. However, the climate at
Qarn Alam is considered to be somewhat extreme with respect to maximum and
minimum temperatures. According to local reports, the maximum temperatures in the
summer regularly exceed 50 oC and the minimum temperatures in winter may fall
lower than 5 oC.
Based on meteorological data recorded in Fahud for the year 2001, the mean annual
temperature is 29.3°C. The mean monthly temperatures range from 18.6 oC in January
(with mean minimum of 11.2oC and mean maximum of 25.8oC) to 37oC in July (with
mean minimum of 29.4 oC and mean maximum of 43.9 oC). The maximum and
minimum absolute temperatures are 48.2oC and 7 oC respectively.
The mean annual rainfall in Fahud area during the year 2001 is nil. There is very little
inter-annual variation in temperature, but the annual rainfall is exceptionally variable
between years with little indication of seasonality. Rain has been known to fall in
nearly all months of the year, although the mean monthly rainfall was the highest
during February and April, with a secondary peak in August.
Tropical storms and cyclones have been known to enter the Gulf of Oman bringing
torrential rain to the coast, but are rarely so widespread to reach as far west into
central Oman. Storms or cyclones are practically unknown at the height of the
monsoon during the summer months of July to September. However, one rare tropical
storm affected much of central Oman during the last week of July 1995 bringing 200
mm of rain to the Hajar mountains and flooding its alluvial plains. Similar rains were
experienced in central Oman during the winter months of 1998. The climatic charts
are presented in Figure 5.5.
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Figure 5.4A: Iso-salinity Map of Fars Aquifer
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Figure 5.4B: Iso-salinity Map of UeR Aquifer
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MONTHLY ABSOLUTE MAXIMUM & MINIMUM
MONTHLY AVERAGE RAINFALL RECORDED AT FAHUD -
TEMPERATURE RECORDED AT FAHUD - (1985 - 2001)
100
(1985 - 2001)
100
90
90
80
80
70
70
60
60
50
50
40
40
30
30
20
20
10
10
0
0
Max. Temp.
Min. Temp.
MONTH
Monthly Variations at Yibal
(Recorded at Fahud)
MONTHLY ABSOLUTE MAXIMUM & MINIMUM
MONTHLY AVERAGE RAINFALL RECORDED AT QARN ALAM -
TEMPERATURE RECORDED AT QARN ALAM - (2000 - 2001)
100
(2000 - 2001)
100
90
90
80
80
70
70
60
60
50
50
40
40
30
30
20
20
10
10
0
0
Max. Temp.
Min. Temp.
MONTH
Monthly Variations at Qarn Alam
(Recorded at Qarn Alam)
Figure 5.5: Climatic Charts for Yibal - Qarn Alam Area
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Environmental Assessment:
2002 Review and Update
Ambient Air Quality
Very limited air quality studies have been conducted anywhere in PDO concession
area since PDO’s exploration and production activities started. For either Yibal or
Qarn Alam asset, no data are available on the ambient air quality from the previous
EIA reports (Reference 1). It is generally believed that ambient air quality within
PDO concession area is of no significance due to two reasons. Firstly, there are no
human settlements close to any operational facilities in the entire PDO concession
area. Secondly, there are not many air emissions sources in PDO and the emission
loads are not considered very significant.
However, in the absence of any measurements, the significance of ambient air quality
cannot be established. Based on the uneven distribution of the emission sources,
relatively shorter stack heights and atmospheric inversion conditions expected during
winter nights, the concentration of some pollutants in ground level air may be
elevated in certain locations and in PDO camps at sometimes. Therefore, it is
necessary that air quality surveys be undertaken at periodic intervals at selected
locations to determine whether the air quality in the asset is within the permissible
limits.
5.7
Ambient Noise
No data are available on the ambient noise levels within the asset. It is believed that
the ambient noise levels in this region are of no significance due to the fact that there
are no human settlements close to any operational facilities. The high noise generating
sources in the operating facilities of gas asset as well as those of the other production
and service assets in each area are unlikely to have any impact on the human
settlements. However, they may have an impact on the noise levels in the PDO and
contractor camps.
Therefore, it is necessary that noise surveys be undertaken at periodic intervals at
selected locations to determine whether the noise levels in the accommodation areas
are within the permissible limits.
5.8
Flora and Fauna
5.8.1
Flora
With rainfall being very scanty and erratic, the fog moisture largely influences the
vegetation in this region. The native vegetation is composed of desert plants and
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grasses, and trees are rarely seen. The distribution pattern of vegetation is dependent
on the water drainage pattern and the presence of adequate sand or fissures in the
bedrock for plant establishment.
The sabkha of Umm as Samim and the low sand dunes in Yibal asset are unvegetated. Even the gravel plains are mostly un-vegetated, with sparse vegetation in
the wadis. The main trees in the wadis are the ‘ghaf’ (Prosopis cineraria) and ‘samra’
(Acacia tortilis), both of which are native to Oman. Shrubs consist mainly of
unpalatable species such as Rhazya, Tephrosia and Zygophyllum, which are
perennial. Grazing and browsing by camels and goats has altered the natural
vegetation of the area, affecting the composition of both the perennial and annual
species. The trees are heavily browsed and all species show severe browse lines.
The vegetation in Yibal - Qarn Alam areas can be broadly classified as the AcaciaZygophyllum-Heliotropium vegetation type. This vegetation type is typical of the
central gravel plains of Oman. Further classification recognizes two plant
communities occupying two habitats, the gravel plains and the wadis. The gravel
plains have very sparse vegetation consisting of no more than 10 species most of
which are unpalatable subshrubs. The wadis and drainage channels contain trees of
Acacia tortilis and in a few places Prosopis cineraria. There are no endemic or
regionally endemic species in this region.
5.8.2
Fauna
Wildlife is very rare in this region. There are no large mammals, except for domestic
livestock are sited. Rodents and reptiles are the main wildlife recorded in this region.
Among mammals, Red Fox, Ruppel’s Sand Fox ( Vulpes rueppellii sabaea) and Sand
Cat ( Felis margarita harrisoni) are known to occur in Yibal asset area. Ruppel’s Sand
Fox and Sand Cat are both listed in the IUCN Red List and Oman Regional List as
‘Data Deficient’. The largest mammals that occur in the Qarn Alam Asset area are the
mountain gazelle and the rheem gazelle, both of which qualify under the IUCN world
Red List and the regional Red List threat categories. A few smaller mammals, mostly
gerbils, jirds and jerboas are likely to be present in the vegetated areas.
Twenty four species of birds, including sixteen breeding types are recorded in Yibal
asset area.. Breeding status is confirmed for seven species including the Golden Eagle
and Egyptian Vulture. There is no regional Red Data List for birds and their
threatened status in Oman is yet to be established. A number of birds are attracted to
the artificial lake near PDO’s Main Camp, which has increased the total number of
species of migratory birds in the area.
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Bird surveys at Qarn Alam asset area reveal an estimate of 96 species, 78 at Qarn
Alam and 18 at Saih Rawl. The majority of the species are migratory. However, there
are 12 species which are believed to breed in the Qarn Alam Asset. Of these, breeding
records are confirmed for 4 species, 5 species probably breed, and 4 species possibly
breed in the area. There is no regional Red List for birds, and their threatened status in
Oman is yet to be established.
A number of reptiles are expected to be present in both asset areas, mostly in the
vegetated wadis. Several of these species are endemic to Arabia. There are no
regional Red Data lists for reptiles and their status in Oman is not yet established.
Reptiles are not well covered in the IUCN World Red list.
5.9
Human Settlements
There are no major settlements in Yibal asset outside the PDO camp, except for Wadi
Al Umairy. This village has 27 household with a total population of 102 persons.
Other than this village, there are no towns or bedouin settleme nts within the asset
area. Main occupation is date farming and animal husbandry. The livestock include
camels and goats, and they use the wadi plains of Wadi Jibal, Wadi Huwaisa, Wadi
Aswad and Wadi Mutrah to graze. Three water troughs are provided for the camels by
PDO in the asset.
There are no towns within the Qarn Alam asset area and bedouin (nomadic or seminomadic) settlements are relatively few in number and nowhere permanent. A total of
approximately 20 families are known to PDO in the area. These families utilise wadis
in particular, exploiting browsing/grazing opportunities for their livestock, comprising
goats and camels. Additional camels and goats belonging to settlements in the
Fahud/Lekhwair area or from south of the Qarn Alam Asset also use wadis to browse
and graze.
Ghaba Guest House/Motel with accompanying filling station and shop is situated on
the main Muscat-Salalah highway, close to Ghaba North Gathering Station.
Table 5.3: Human Settlements in Yibal and Qarn Alam Asset Areas
Village / Camp
PDO Camp
Contractors Camp
Wadi Al Umairy
Location
Total
Current
Number
Total
of
Population
Housing
Units
YIBAL ASSET AREA
Main Camp
216
180
Outside Main Camp
270
900
60 km southwest of
27
102
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Employment in PDO
Employment in PDO
Dates farming and
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Main Camp
PDO camp
Contractor camp
Wadi Alumayri
Sayh Ar Rul
Wadi Mihul
Ghabah
Al Haqaf
Qarat Al Malh
Wadi Al Ghubur
Bedouin
populations
5.10
animal husbandry
QARN ALAM ASSET
Main Camp
155
201 rooms
Outside main camp
1074
460
130 km west of
102
27
Qarn Alam Camp
40 km west of Qarn
331
7
Alam Camp
45 km northwest of
77
19
Qarn Alam Camp
16km northeast of
23
1
Qarn Alam Camp
40 km northeastof
64
15
Qarn Alam Camp
45 km northeast of
25
9
Qarn Alam Camp
86 km southwest of
15
1
Qarn Alam Camp
Not reported
None
None
PDO staff
Contractor staff
Farming and trading
Farming and trading
Farming and trading
Trading
Farming and trading
Farming and trading
Farming and trading
None
Land Use
The land use in this region had undergone significant change due to PDO’s
exploration and production activities and facilities. Large areas of barren desert land
are converted into industrial areas and significant extent of land area is not vegetated.
There is no subsistence farming or date orchards within the asset area. The wadi
plains are used by local livestock for grazing.
The details of land area developed by PDO for locating the production and associated
facilities are summarised below in Table 5.3.
Table 5.4: Land Use in Yibal and Qarn Alam Assets
Facility
Total Area
YIBAL ASSET
Total asset area
Yibal-A Production Station
Government Gas Plant, Government Butane
Plant and Butane Storage and Loading Facility
Yibal-B Gathering Station
Yibal-B Gathering Station
Yibal-B Gathering Station
Yibal Power Station
PDO Main Camp + Contractor’s Camps
QARN ALAM ASSET
Total asset area
Production stations
Gathering stations
Power stations
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5830 km2
182549 m2
70999 m2
90184 m2
65694 m2
42953 m2
30645 m2
205640 m2
18,900 km2
836,000 m2
132,800 m2
35,000 m2
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5.11
Environmental Assessment:
2002 Review and Update
Social Infrastructure and Public Services
Like most areas in central Oman, Yibal and Qarn Alam asset areas are very thinly
populated and therefore has limited social infrastructure. The recent developments
associated with the oil industry have assisted to provide access to the necessary civic
services.
•
Water and Electricity
Groundwater is the only water resources in the region. Since the groundwater is not of
potable quality, demineralised water from PDO’s RO plant is used for potable water
in PDO and contractor camps. PDO also provides to some local communities potable
water from its RO plant, free of charge.
In both assets, the total power requirements are met with captive power generation. In
Yibal, there is a gas turbine power plant of 80 MW generation capacity. In Qarn Alam
asset, there are two power plants one in Saih Rawl with 60 MW capacity and another
in Saih Nihayda with 30 MW capacity.
•
Roads and Communications
Yibal is connected to Fahud by an undivided two-lane blacktopped road. Qarn Alam
is connected to Fahud by graded road. No major road passes through the Qarn Alam
asset. In addition, PDO maintains an extensive network of graded roads in both assets.
All these roads are accessible to the local populations.
There is an airstrip in Qarn Alam and regular flights are operated from Muscat and
southern assets. There is also an airstrip in Yibal, but no flights are operated at
present. Yibal passengers are transported by bus to/from Fahud airport, which has
regular flights. All flights within PDO’s concession area are restricted to only PDO
staff and its contractors.
PDO maintains a network of telephones lines and radio transmitters in the concession
area. The region is also covered by GSM telephone service.
•
Education
There are no schools in either of the asset areas.
•
Health Services
There are no government health care facilities in Yibal or Qran Alam asset areas.
Private health-care facilities (clinic and ambulance services) are available within
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PDO's residential camps. These facilities are generally made available to the
surrounding communities.
5.12
Archaeological, Cultural and Recreational Resources
The literature search and a walk-through field survey have shown no evidence of
archaeological sites in Qarn Alam asset. The cultural resources are limited to a
mosque located in PDO’s main camp. There are also no recreational facilities, other
than those located within PDO’s main camp.
Within Yibal asset, Umm as Samim, the largest sabkha of the Arabian Peninsula, and
one of the largest in the world, can possibly be classified as a feature of visual
amenity to those who find beauty in wilderness. This area, in the south of Yibal asset
and extreme northwest of Qarn Alam asset and completely featureless, totally unvegetated, with the soil surface breaking into salt-encrusted polygons. There are no
archaeologically or culturally important sites in the asset. The recreational sites are
limited to those present in the PDO main camp. The environmentally significant sites
within Yibal asset are summarised in Table 5.4.
Table 5.5: Environmentally Significant Areas in Yibal Asset
Area
Umm as Samim sabkha
Wadi Al Ayn
Wadi Yibal and Wadi Aswad
Wadi Al Umairy
Archaeological Sites
Cultural sites
Areas of exceptional natural beauty
Significance
The largest salt pan in the Arabian Peninsula; unique historical
formation, hydro-geological and palaeo-climatic history
It is within the area declared as yellow zone of the Water
Protection Zones in Oman.
These wadi plains are used for grazing by livestock and they
provide a habitat for small fauna such as rodents, geckos,
invertebrates and birds
Agricultural land
None
None
None
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6
ENVIRONMENTAL IMPACTS
6.1
Methodology
Environmental Assessment:
2002 Review and Update
In this chapter, the significant environmental hazards and effects present in the asset
are identified and assessed based on the methodology outlined in PDO's document
GU-195 "Environmental Assessment Guideline" (Reference X). In PDO's
terminology, the term "environmental hazard" is used for the sources (causes) of
potential environmental effects, and term “effect” is used for the impact.
The environmental effects may include all those that are beneficial or adverse, short
or long term (acute or chronic), temporary or permanent, direct or indirect, and local
or strategic. The adverse effects may include all those leading to, harm to living
resources, damage to human health, hindrance to other activities, impairment of
quality for use, reduction of amenities, damage to cultural and heritage resources, and
damage to physical structures.
For each identified potential environmental effect, the associated environmental risk
is assessed based on its likelihood and significance. The likelihood (frequency) of
occurrence of an effect, the significance of its consequence and the potential risk level
are evaluated qualitatively as described below:
-
Rating of likelihood (frequency) of occurrence of an effect:
A (very low), B (low), C (medium), D (high), E (very high)
-
Rating of significance of its consequence:
slight, minor, localized, major and massive
-
Rating of potential environmental risk level:
low, medium, high and extreme
The criteria used for rating the environmental risk are discussed in detail in
Appendix 3.
6.2
Potential Environmental Hazards and Effects
The potential environmental hazards and effects associated with the various activities
performed in the asset are presented in Appendix 4. These are presented in the form of
matrices. In the following sections, the impacts identified are qualitatively assessed
according to the methodology presented in Section 6.1.
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6.3
Environmental Assessment:
2002 Review and Update
Beneficial Impacts
Several beneficial environmental impacts accrue from the asset activities. They
include socio-economic, socio-cultural and ecological benefits. These beneficial
impacts outweigh the adverse impacts, which are discussed in the subsequent
sections. The beneficial impacts from the asset are on the economy, employment,
local amenities and ecology. These impacts are discussed below. They are however
not rated or ranked as per the methodology discussed in Section 6.1 since PDO's
rating criteria apply for adverse impacts only. Therefore, only descriptive treatment is
given for the magnitude and significance of the beneficial impacts.
•
Industrial Development and Economy
On behalf of the government, gas asset processes the natural gas (un-associated gas)
produced from gas wells located in Yibal and Qarn Alam assets. The processed gas is
delivered via SOGL to various consumers in Oman and to Oman LNG plant in Sur
for liquefaction and export. Currently, the total quantity of natural gas delivered by
gas asset is about 28.5 million Sm3/d. Within Oman, natural gas is presently used as
fuel gas in the various utility power plants. There are several new power plants under
construction in Oman, which will use the natural gas supplied by gas asset. In
addition, several petrochemical industries are under development in Oman, which
will use natural gas as the feedstock. Thus, gas asset plays an important role in the
industrial development of Oman and consequently the national economy.
•
Employment
The total number of permanent staff directly employed by gas asset is about 100. The
number of permanent staff employed by the contractors working for gas asset is about
400. In addition, a large number of persons, including local populations are also
provided indirect employment to provide a number of supporting services to gas asset.
Providing service to PDO is the only alternative employment for the local
communities, whose main occupation is farming and raising livestock. Therefore, the
beneficial impact on employment is also significant.
•
Amenities
PDO shares several amenities developed within its concession area with the local
populations. They include the access roads, power supply, potable water supply,
clinical facilities and telecommunication facilities. In addition, PDO provides
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financial and other material assistance to local schools, local bodies and cultural
events.
•
Ecology
While some adverse impacts on ecology may be expected from the asset activities, a
few direct beneficial impacts on the ecology also exist. The most significant is the
greening of the desert by re-using treated sewage effluents. The land within the PDO
main camp and the contractor camps is significantly vegetated with trees, shrubs and
lawns. The significant vegetal cover developed in the asset has provided a habitat for
the native fauna, most importantly birds and terrestrial invertebrates.
6.4
Impacts on Natural Resources
The potential environmental effects on the natural resources and the associated
environmental hazards are listed below:
Environmental Hazards
- Consumption of mineral resources
- Land take
Potential Environmental Effects
- Depletion of natural mineral resources
- Claim of local assets
Large quantities of gas (~28.5 million Sm3/d) continuously extracted will result in the
depletion of petroleum reserves in the asset. However, the environmental impact and
risk resulting from this activity is not discussed here since this forms the core activity
of the asset.
It may be noted that gas asset is not a direct consumer of groundwater. Groundwater
is required only for domestic consumption of the gas asset field staff. These staff are
provided accommodation by the production assets in Yibal and Qarn Alam camps.
Similarly, no construction materials are routinely consumed by gas asset.
The land taken by gas asset for locating gas processing facilities may be considered to
have competing users. However, the entire area of land on which gas asset facilities
are located has no alternate use, due to the poor soil quality, lack significant
vegetation and harsh environmental conditions. The total land take of gas asset is less
than 8 ha.
Therefore, the overall potential risk on natural resources is rated as negligible.
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6.5
Environmental Assessment:
2002 Review and Update
Impacts on Air Environment
The potential environmental effects on the air environment and the associated
environmental hazards are listed below:
Environmental Hazards
- Release of gaseous emissions from stationary sources
- Release of gaseous emissions from mobile sources
- Release of fugitive emissions
- Generation of noise from stationary sources
- Generation of noise from mobile sources
Potential Environmental Effects
- Global warming
- Air pollution
- Noise pollution
•
Global Warming
CO2 and methane emissions from the asset have a potential to contribute to global
warming. Since there is virtually no venting in the asset, methane emissions are
negligible. CO2 emissions from stacks, flares and vehicles are of the order of 500 tpd.
This quantity is not large enough to contribute significantly to global warming, when
compared to the land area covered by the asset. Based on the above discussion, the
overall impact on global warming is rated as below:
Impact Rating
Nature of impact (beneficial / adverse)
Duration of impact (short term / long term)
Likelihood of occurrence (very low / low / medium / high / very high)
Significance of impact (slight / minor / localized / major / massive)
Potential risk level (low, medium, high and extreme)
•
Global Warming
Adverse
Short term
Very low
Slight
Low
Air Pollution
Gas turbines and vehicles account for most of the emission loads in the asset. These
emissions release pollutants such as NOx, SO 2, CO and unburnt hydrocarbons into air.
The total emission loads in the asset are estimated to be quite low for each pollutant
(<5 tpd for any species). Considering that they are released over a large area, they are
not expected to lead to any significant degradation of air quality in the airshed.
Further, most of the asset areas are uninhabited. Therefore, it is reasonable to assume
that the overall air quality in the asset areas will be mostly unaffected by the air
emissions from gas asset.
However, the potential adverse impacts on air quality within and near the areas where
the gas processing facilities are located may not be assumed insignificant. Fugitive
emissions from gas processing facilities may release hydrocarbon gases and vapours
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into the workplace and the near ambient. The stack emissions, due to short stack
heights (typically ~15m) may not disperse well in air, particularly during adverse
meteorological conditions (such as inversion). In the absence of any data on
workplace or ambient air quality and regular monitoring of air emissions, the
likelihood of degradation of ambient air quality at locations close to gas processing
facilities in the asset shall have to be considered medium. Based on the above
discussion, the overall impact on ambient air quality is rated as below:
Impact Rating
Nature of impact (beneficial / adverse)
Duration of impact (short term / long term)
Likelihood of occurrence (very low / low / medium / high / very high)
Significance of impact (slight / minor / localized / major / massive)
Potential risk level (low, medium, high and extreme)
•
Air Pollution
Adverse
Long term
Medium
Minor
Medium
Noise Pollution
Both stationary and mobile noise generating sources can adversely affect the ambient
noise levels. Since the noise from mobile sources is intermittent as well as transient,
most of the potential impacts are due to the continuous and stationary sources such as
gas turbines, heaters, air compressors, flares, pumps, motors and other rotating
equipment. While sufficient data on source noise levels are not available, it is
reasonable to expect that their impacts will be highly localized and limited to less than
1 km distance. There are no human settlements in the asset areas except for PDO and
contractors camps. It is however likely that some areas in these camps may be
subjected to elevated noise levels. No data are currently available to check whether
there is any breach of regulatory standards.
Based on the above discussion, the impact on ambient noise is assessed as below:
Impact Rating
Nature of impact (beneficial / adverse)
Duration of impact (short term / long term)
Likelihood of occurrence (very low / low / medium / high / very high)
Significance of impact (slight / minor / localized / major / massive)
Potential risk level (low, medium, high and extreme)
6.6
Increase in Ambient
Noise Levels
Adverse
Long term
Low
Minor
Medium
Impacts on Water Environment
Gas asset is does not extract any groundwater, since the asset activities do not require
any water consumption. Domestic water for gas asset staff is provided directly by the
production asset where the gas asset staff are accommodated. Similarly, no liquid
effluents are generated or discharged in the asset areas. Therefore, gas asset activities
no impact on the water environment.
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6.7
Environmental Assessment:
2002 Review and Update
Impacts on Land Environment
The potential environmental effects on the land environment and the associated
environmental hazards are listed below:
Environmental Hazards
- Land take
- Land disposal of solid wastes
- Accidental spillage of hazardous liquids
Potential Environmental Effects
- Alteration of land use
- Loss of vegetation
- Land contamination
As noted in Section 6.4, the total land take for the installation of gas asset facilities is
less than 8 ha. The land in the asset areas is barren, very sparsely vegetated and has no
alternate use. The extent of land take is marginal compared to the total available land
in the asset. Therefore impacts on land use and vegetation due to the activities of gas
asset will be insignificance.
The land disposal of solid wastes and accidental spillage of hazardous liquids have
potential for land contamination. With respect to solid wastes, only two types of solid
wastes (oil sludge and pigging waste) are generated in the asset, both of which are not
continuous. None of these wastes is disposed on land. Instead, these wastes are sent to
the nearest PDO’s waste management centre for proper disposal.
With respect to accidental spillage of hazardous liquids, no major hazardous
chemicals are used in the asset. Occasional oils leaks occur from the condensate lines
and rotating equipment. Currently no data are available on accidental spills and leaks,
and they are reported in the asset. In the absence of any data, it is assumed that the
likelihood of occurrence is assumed to be medium. However, the significance of
impact will be minor since any contamination resulting from such oil leaks will be
highly localised.
Based on the above discussion, the impact on land contamination is assessed as
below:
Impact Rating
Nature of impact (beneficial / adverse)
Duration of impact (short term / long term)
Likelihood of occurrence (very low / low / medium / high / very high)
Significance of impact (slight / minor / localized / major / massive)
Potential risk level (low, medium, high and extreme)
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Land
Contamination
Adverse
Long term
Medium
Minor
Medium
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6.8
Environmental Assessment:
2002 Review and Update
Impact on Ecology and Wildlife
The potential environmental effects on the ecology and wildlife and the associated
environmental hazards are listed below:
Environmental Hazards
- Land take
- Road travel
Potential Environmental Effects
- Loss of endangered flora
- Loss of endangered fauna
- Threat to wildlife habitats
There are no endangered flora and wildlife habitats in the asset. The populations of
fauna in the asset are very limited. The environmentally significant Arabian Oryx
Nature Reserve boundary is just touches the asset boundaries. The road traffic for
transportation of materials and men is not high. Therefore the impact on ecology is
considered negligible.
6.9
Impact on Social Environment
Under social environment, employment, agriculture, animal husbandry, native
lifestyle, cultural heritage, public health and safety, landscape and aesthetics are
considered. Most of the impacts on social environment are beneficial, which are
discussed in Section 6.2. There are also a few adverse impacts on the social
environment.
The asset area is very thinly populated and there are no human settlements except for
PDO and contractor camps. Therefore, the significance and magnitude of adverse
impacts on social environment are very limited. The only direct adverse impact on
social environment that may need to be considered is the public safety and health of
the transient populations across the asset.
The hazards with potential impact on public safety and health are listed below:
Environmental Hazards
- Handling and storage of hazardous substances
- Road travel
Potential Environmental Effects
- Public safety and health
Storage and handling of gas in the asset facilities have the potential for adverse effects
on public health and safety in the event of significant release into the environment
following structural failure and loss of containment. This may lead to fire, explosion,
and toxicity. Considering that the gas asset facilities are located far away from huma n
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settlements, it is unlikely that general public are not exposed to any accidental
consequences. However, the plant staff will be exposed to these consequences.
The road vehicles used by the asset staff for the transportation of men and materials
within PDO’s concession areas may pose a public safety and health risk in the event
of road accidents. However, the risk is assessed to be low considering that the asset
does not routinely transport hazardous cargo and traffic density on the roads is
generally low.
Based on the above discussion, the impacts on public health and safety are assessed as
below:
Impact Rating
Nature of impact (beneficial / adverse)
Duration of impact (short term / long term)
Likelihood of occurrence (very low / low / medium / high / very high)
Significance of impact (slight / minor / localized / major / massive)
Potential risk level (low, medium, high and extreme)
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Public Health and
Safety
Adverse
Short term
Low
Localized
Medium
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7
Environmental Assessment:
2002 Review and Update
SUMMARY OF SIGNIFICANT ENVIRONMENTAL EFFECTS AND
MITIGATION MEASURES
The identification and assessment environmental hazards and effects in the asset are
discussed in Chapter 6. All adverse environmental effects with medium to extreme
risk are considered as significant environmental effects. In this chapter, the additional
mitigation measures required for minimizing the environmental consequences from
these effects are developed. It may be noted that PDO has a comprehensive
environmental management plan as a part of the HSE management system (refer
Chapter 2), which is implemented in the asset. No change in the existing
environmental management system is required. However, certain additional
mitigation measures will reduce the potential environmental risk and improve the
overall environmental performance.
The significant environmental effects are listed below along with explanatory notes.
Environmental
Effect
Impact Rating
Potential
Risk Level
Comments
Land
contamination
•
•
•
•
Adverse
Long term
Medium occurrence
Minor significance
• Medium
risk
Air pollution
•
•
•
•
Adverse
Long term
Medium occurrence
Minor significance
• Medium
risk
Noise pollution
•
•
•
•
Adverse
Long term
Low occurrence
Minor significance
• Medium
risk
Public safety
and health
•
•
•
•
Adverse
Short term
Low occurrence
Localised
significance
• Medium
risk
• Oil leaks from condensate lines
may occur.
• Accidental leaks and spills of oils
and chemicals are not monitored
and reported.
• Fugitive emissions from gas
processing facilities may occur.
• No monitoring data are available
demonstrating compliance with
workplace and ambient air quality
standards in and around gas
processing facilities.
• No monitoring data are available
demonstrating compliance with
workplace and ambient noise
standards in and around gas
processing facilities.
• Accidental failure of gas handling
and storage facilities can lead to
fire, explosion and toxicity
The recommended additional mitigation measures for reducing the environmental risk
levels and improving the environmental performance are listed below against each of
the environmental specifications of PDO, viz., SP-1005 to SP-1012.
©HMR Environmental Engineering Consultants
Oman’s Environmental Consultancy
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Gas Asset
Specification
SP-1005: Specification
for Emissions to
Atmosphere
SP-1006: Specification
for Aqueous Effluents
SP-1007: Specification
for Accidental Releases
to Land and Water
SP-1008: Specification
for Use of Energy,
Materials and Resources
SP-1009: Specification
for Waste Management
SP-1010: Specification
for Environmental Noise
and Vibration
SP-1011: Specification
for Flora and Fauna
SP-1012: Specification
for Land Management
SP-1170: Specification
for Management of
Naturally Occurring
Radioactive
Environmental Assessment:
2002 Review and Update
Areas of Non-compliance or
Concern
• No monitoring data are available
demonstrating compliance with
workplace and ambient air
quality standards in and around
gas processing facilities.
• None
Recommended Additional
Mitigation Measures
• Work place and ambient air
quality shall be monitored
periodically in and around gas
processing facilities.
• Accidental leaks and spills of oils
and chemicals are not monitored
and reported.
• Efficient use of fuel and water in
the field activities of the asset is
not demonstrated.
• None
• All accidental leaks and spills
shall be monitored and
reported.
• Fuel conservation measures
shall be promoted.
• No monitoring data are available
demonstrating compliance with
workplace and ambient noise
standards in and around gas
processing facilities.
• None
• Work place and ambient noise
levels shall be monitored
periodically in and around gas
processing facilities.
• None
• None
• None
• None
©HMR Environmental Engineering Consultants
Oman’s Environmental Consultancy
• None
• None
• None
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Gas Asset
8
Environmental Assessment
2002 Review and Update
REFERENCES
1.
WS/Atkins, Gas Asset Team Environmental Assessment Report, PDO, November
1999
2.
PDO, HEALTH, SAFETY AND ENVIRONMENT GUIDELINE - Environmental
Assessment GU 195, July 2002
3.
SIEP, EP 95-0377, Quantifying Atmospheric Emissions, September 1995
©HMR Environmental Engineering Consultants
Oman’s Environmental Consultancy
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Gas Asset
Environmental Assessment:
2002 Review and Update
APPENDIX 1: ORGANIZATION RESPONSIBLE FOR PREPARATION OF
THE REPORT
HMR Environmental Engineering Consultants, Oman are responsible for the
preparation of this report on environmental assessment of Gas asset area. HMR is the
leading environmental engineering consultancy in Oman. HMR specializes in the
fields of environmental management, water resources management, environmental
assessment, environmental auditing, environmental monitoring, pollution control and
environmental training.
HMR has a large pool of environmental engineers and scientists, who have work
experience throughout the world and the Arabian Gulf. HMR also has technical
collaborations and associations with a number of international engineering consulting
companies. HMR is registered with the World Bank as well as with the Ministry of
Regional Municipalities and Environment, Sultanate of Oman.
The following HMR Staff are responsible for the technical component of this report.
Name of EIA Team
Member
Dr. Laks M. Akella
Position in HMR
C. S. Shaji
Consultant
Robert Spence
C. M. Sushanth
Babu Krishanan
Krishnasamy
Vinod Gopinath
Senior Consultant
Consultant
Consultant
Consultant
Environmental
Technician
IT Consultant
Shubha Srinivas
Senior Consultant
Position in EIA
Team
Team Leader and
Project Manager
EIA Expert
Role in Project Execution
EIA Expert
EIA Expert
EIA Expert
EIA Expert
EIA Expert
Project management, data
analysis and editorial review
Data collection, site audit and
report preparation
Data collection and site audit
Data collection and site audit
Data collection and site audit
Data collection and site audit
Data collection and site audit
Cartographer
Cartography
On behalf of the client, Petroleum Development Oman, the following individuals are
responsible for the review of the EIA report at all stages of the study.
Name of Reviewer
Mr. Ahmed Al Sabahi
Mr. Fareed Bin Ali Al -Hinai
Position in PDO
Environmental Advisor
Gas HSE Supervisor
©HMR Environmental Engineering Consultants
Oman’s Environmental Consultancy
Role in Project Development
Reviewing the report
Reviewing the report
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Environmental Assessment:
2002 Review and Update
APPENDIX 2: FUEL GAS ANALYSIS
Saih Nihayda
Gas station
GGP
81.70
72.12
Ethane, in % v/v
4.78
9.12
Propane, in % v/v
2.08
7.15
i-Butane, in % v/v
0.61
2.01
n-Butane, in % v/v
0.79
3.25
i-Pentane, in % v/v
0.36
1.05
n-Pentane, in % v/v
0.33
1.18
Hexane +, in % v/v
0.41
0.92
Nitrogen, in % v/v
8.52
2.47
0.42
1.21
0
380
Parameter
Methane, in % v/v
Carbon Dioxide
in % v/v
Hydrogen Sulphide
in ppm
©HMR Environmental Engineering Consultants
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Gas Asset
Environmental Assessment:
2002 Review and Update
APPENDIX 3: PDO'S ENVIRONMENTAL RISK EVALUATION CRITERIA
Rating of Consequence of Effect on Environment
Slight effect : Local environmental damage. Within the fence and within
systems. Negligible financial consequences
Minor effect: Contamination. Damage sufficiently large to attack the
environment. Single exceedence of statutory or prescribed criterion. Single
complaint. No permanent effect on the environment.
Localized effect: Limited loss of discharges of known toxicity. Repeated
exceedence of statutory or prescribed limit. Affecting neighborhood.
Major effect: Severe environmental damage. The company is required to
take extensive measures to restore the contaminated environment to its
original state. Extended exceedence of statutory limits
Massive Effect:Persistent severe environmental damage or severe nuisance
or nature conservancy extending over a large area. In terms of commercial or
recreational use, a major economic loss for the company. Constant, high
exceedence of statutory or prescribed limits
HMR Environmental Engineering Consultants
Oman’s Environmental Consultancy
Rating of Frequency of Occurrence
A.
B.
C.
D.
E.
Very
Low :
Medium High:
Very
low:
Has
Has
Occurs
high:
Not
occurred occurred several
Occurs
heard of in other
in oil
times a
several
but could industry and gas
year in
times a
occur
industry oil and
year in
gas
PDO
industry
LOW RISK
MEDIUM RISK
HIGH RISK
EXTREME
RISK
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Environmental Assessment:
2002 Review and Update
APPENDIX 4: ENVIRONMENTAL HAZARDS AND EFFECTS IDENTIFICATION MATRIX: GAS ASSET
Environmental Sensitivities
Landscape & Aesthetics
Public Health & Safety
Cultural Heritage
X
X
X
Native Lifestyle
X
X
X
Agriculture & Animal Husbandry
Wildlife Habitats
X
X
X
Social
Environment
Employment
Fauna
X
X
X
X
Ecology and
Wildlife
Flora
X
X
X
X
Soil Quality
Land
Environment
Loss of Vegetation
Marine Water Quality
Hydrogeology & Ground Water Quality
Water
Environment
Surface Hydrology & Water Quality
Ambient Noise
Ambient Air Quality
Air
Environment
Climate (Global Warming)
Claim on Local Assets
Groundwater Resources
Mineral Resources
Natural
Resources
Land Use
Environmental Hazards
Land take
For installation of project facilities
For drilling of gas wells
For laying oil/gas pipelines
For laying access roads
X
X
Utilization of Mineral Resources
For production of gas
X
Utilization of Human Resources
X
Employment of permanent workers
Release of Air Pollutants
Gaseous emissions from stationary
sources
Gaseous emissions from mobile
sources
HMR Environmental Engineering Consultants
Oman’s Environmental Consultancy
X
X
X
X
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Environmental Assessment:
2002 Review and Update
Environmental Sensitivities
Landscape & Aesthetics
Public Health & Safety
Cultural Heritage
Native Lifestyle
Agriculture & Animal Husbandry
Social
Environment
Employment
Wildlife Habitats
Fauna
Ecology and
Wildlife
Flora
Soil Quality
Land
Environment
Loss of Vegetation
Marine Water Quality
Hydrogeology & Ground Water Quality
Water
Environment
Surface Hydrology & Water Quality
Ambient Noise
Ambient Air Quality
Air
Environment
Climate (Global Warming)
Claim on Local Assets
Groundwater Resources
Mineral Resources
Natural
Resources
Land Use
Environmental Hazards
X
Accidental release of toxic gases and
vapours
Release of Energy into Atmosphere
Hot gases from flares and stacks
High level noise from stationary
sources
High level noise from mobile sources
X
X
Discharges of Liquid Effluents
Accidental spillage of hazardous
liquids
X
X
Disposal of Solid Wastes
Handling and transport of hazardous
wastes
Functional Activities
Pipeline transport of gas
Road transport of hazardous
substances
HMR Environmental Engineering Consultants
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X
X
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Gas Asset
Environmental Assessment:
2002 Review and Update
Environmental Sensitivities
Bulk storage of hazardous substances
Road travel
Note: Filled-in cells indicate potential interaction and blank cells indicate no or negligible interaction.
HMR Environmental Engineering Consultants
Oman’s Environmental Consultancy
Landscape & Aesthetics
Public Health & Safety
Cultural Heritage
Native Lifestyle
Agriculture & Animal Husbandry
Social
Environment
Employment
Wildlife Habitats
Fauna
Ecology and
Wildlife
Flora
Soil Quality
Land
Environment
Loss of Vegetation
Marine Water Quality
Hydrogeology & Ground Water Quality
Water
Environment
Surface Hydrology & Water Quality
Ambient Noise
Ambient Air Quality
Air
Environment
Climate (Global Warming)
Claim on Local Assets
Groundwater Resources
Mineral Resources
Natural
Resources
Land Use
Environmental Hazards
X
X
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