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SHale gas Exploration andExploration and Exploitation induced RisksRisks
Risk assessment and environmentalRisk assessment and environmental monitoring related to shale oil and gas with
particular reference to groundwater
A d G i
particular reference to groundwater
Second Annual MeetingAndrew Gunning
Second Annual MeetingBlackpool - June 5-7, 2017
This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 640896.
Risk assessment and environmental monitoring related to shale oil and gasrelated to shale oil and gas
What this talk is about:What this talk is about:
• Risk management related to shale oil & gas;
• Perceptions of risk related to energy;
• Establishing the link between risk management site characterisation and theEstablishing the link between risk management, site characterisation and the monitoring regime;
• How effective characterisation and monitoring can reduce risk in shale oilHow effective characterisation and monitoring can reduce risk in shale oil and gas.
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The Risk management process in SHEER
Context:H d li f t i f thHydraulic fracturing for the exploitation of shale gas
Risks:Environmental: air quality, induced seismicity, groundwater contamination
The ISO 31000:2009 risk management process
Analysis:Case studies of previous events The ISO 31000:2009 risk management process
(ISO, 2009)Case studies of previous eventsData acquisition, analysis and interpretation The Process is iterative and ongoing
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g g
Evaluating riskEvaluating risk
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Evaluating riskEvaluating risk
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Risk matrix – probability vs scale of impact
COMPARE SHALE OIL AND GAS TO:
• Nuclear, Oil & Gas - HIGH IMPACT LOW PROABILITY EVENTS:− Fukishima, Chernobyl, Three Mile island− Deepwater offshore conventional oil and gas – Macondo GoM
• Public perception of shale risks
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• Risks to drinking water aquifers from shale E&P eg EPA Report
Risk matrix – probability vs scale of impactp y p
The SHEER Project (and other programmes) is closely evaluating the risk profile for shale oil and gas
dand…………then looking at ways to reduce risks through recommendations for best practice and risk mitigation
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Overall Objectives for SHEER WP5: Groundwater
WPEU AUS USA
Canada
Review of literature, global risks and EU Basins
WP 5.1
Assess Shale Basins in EU and develop
Generic Risk SettingsGeneric Risk SettingsWP5.2 Data collection, modelling and assessment
f f ll i
WP 5 3
of a frac well - site
D l5.3 Develop Recommendations For Best Practice
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Groundwater Risk AssessmentDeveloped the strategy for the project using the standard approach to groundwater risk assessment : the source - pathway – receptor approachJackson et al (2012) identified the need for baseline hydrogeological conditions to beestablished in areas of the US where unconventional oil and gas developments areplanned and also the need for field testing of potential pathways by which drilling andtesting related to unconventional oil and gas might contaminate drinking wateraquifers.
S b tl th US EPA d t d t d t b tt d t d t ti l
Receptor
Subsequently the US EPA conducted a study to better understand any potential impacts of hydraulic fracturing for oil and gas on drinking water resources.
What they are unable to do in North America is to establish baseline conditions In
Pathway1,000 to 4,000m
What they are unable to do in North America is to establish baseline conditions In Europe, where the development of unconventional oil and gas is still in its infancy, there is an opportunity to establish baseline hydrogeological conditions.
The potential risks to drinking water aquifers as a result of shale developments are related to:1 Contamination through surface spills;
Source
1. Contamination through surface spills;2. The near-well zone, through connection to the formation as a result of casing deformation or a failure in well construction;3. The frac zone, through connection to a drinking water aquifer via an
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3. The frac zone, through connection to a drinking water aquifer via an enhanced permeability pathway.
Risk Screening: Baltic Basin
Parameter Value Risk
D th t T t Sh l 3000 d d
g
Depth to Target Shale ~ 3000 m and deeper
Depth of Drinking Water To 800 m
Shale-Water Separation 2200 m or greater: Wide LOW
S OTectonic Setting Limited LOW
Anthropogenic Activity Conventional Oil & Gas, extensive HIGH
Groundwater Value HighGroundwater Value High
Groundwater Sensitivity High HIGH
Further Investigation MODERATE
Confidence Level GoodConfidence Level Good
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WYSIN Wellsite – Northern Poland
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WYSIN Horizontal Wells
W3H 11 Frac stages June 2016Ordovician sequence at
W2H 11 Frac stages June 2016
3974 mbgl
11 Frac stages June 2016Lower Silurian sequence at 3865mbgl
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Wysin Site – Northern PolandyNESW
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Site planCommunal Water Abstraction from Quaternary sediments 3,500 m3/dayp Quaternary sediments 3,500 m /day
Wysin 3H3H
Wysin Monitoring wells
2H
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WP5.1 2 of 3
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Data Collection and processingContinuous data
p g
Barometric probe: Patm & Tair
D h l b P T & S C dDownhole probes: Pabs, TGW & Spec. Cond.
Intermittent dataSet-up for purging and sampling GW3
One-time GWL measurements
Groundwater samples:
o Purging of well & recording physico chemical parametersRecording physico-chemical parameters during purging ofo Purging of well & recording physico-chemical parameters
o Collection of samples / QA / alkalinity test,
A dit d l b ti i t l t & di l d
parameters during purging of GW4
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o Accredited lab: cations, anions, trace elements & dissolved gases; SUERC for isotopes 16
Groundwater chemistryy
Major ions 5 5 meq/l0Major ions
• Groundwater− Ca-HCO3
Ca
Mg
HCO3
SO4
− Manganese > 50 µg/l− Traces of As, Ba, F- & Sr
• Frac fluid
Na Cl
5 5 meq/l0
• Frac fluid− Na-HCO3?
• Flowback fluid− Na-Cl− Rich in metals: Ba, Br, Li, Mn and Sr focus of post-
frac monitoring
1000 1000 meq/l0
Scale 1:200
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Scale 1:200
Perspectives on data from Wysin so farp y
Typical Quaternary aquiferTypical Quaternary aquifer
• Semi-confined to confined, with limited variations of groundwater levels => heterogeneities
• Recharge mainly occurring in Autumn (2016 data)
• Similar chemistry: Ca-HCO3 water type, with limited temporal variability
Signature of flowback fluid completely different
• No short-term impacts on GW resources from the exploration well / hydraulic fracturing
Groundwater model
• Aquifer behaviourq
• Scenarios for potential impacts – eg timescales
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Wysin monitoring
Monitoring and analysisMonitoring and analysis
of dissolved methane
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Next steps….p
Development of best practice in• Development of best practice in groundwater monitoring
• Risk assessment
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Well Integrity a risk area:g y
Must look at this in the full cycle of exploration, production and decommissioning.
Production can continue for over 25years
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Groundwater contaminationC St d Di k P l i USACase Study : Dimock, Pennsylvania, USA• Cabot Oil & Gas paid US$4.2 million in a settlement over methane pollution of
local groundwater (Osborn et al., 2011)
Three possible causes:1. Leakage through well
casing2 Ph i l di l t f2. Physical displacement of
gas-rich solution3. Hydraulic stimulation of
e isting fract resexisting fractures
• Methane was unrelated to the hydraulic fracturing
• Insufficient baseline studies for proof
(Hammond, 2016)
• Reinforced by retrospective studies
(US EPA, 2015)
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Anthropogenic Featuresp gEg Abandoned wells
Weald BasinWeald Basin
Slide on Wealdon
Site Characterisation needs to take into account:• determining safe stand-offs between frac wells and
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gwater abstraction wells
• estimate risk of anthropogenic features
Risk management processg p
Robust site characterisation d b li it i illand baseline monitoring will
make it much easire to fix problems at an early stage I the projectthe project
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WP 5 Main Team Members
Professor Paul Younger Andrew Gunning
Dr Neil Burnside Dr Catherine Isherwood
Dr Nelly Montcoudiol Tom KellyDr Nelly Montcoudiol Tom Kelly
Dr David Banks Brian Anderson
& others Support staff
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Risk assessment and environmental monitoring related h l il d i h i l fto shale oil and gas with particular reference to
groundwater
ThanksThanks
Andrew GunningAndrew Gunning
Partner, RSKWa t e , S
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