Topic
Well Integrity
Containment and structural integrity of wells throughout their life cycle.
Documents
- 202631 Mar
ALARP in the context of well integrity guidance note
Guidance for titleholders on demonstrating reasonably practicable reduction of well-integrity risks within well operations management plans. It explains gross disproportion, recognised good practice, well-specific risk assessment and precaution under uncertainty. Supported arguments, proportionate analysis and continuing control effectiveness underpin the demonstration; no single methodology is prescribed.
- 202631 Mar
Change to the titleholder with operational control of activities guidance note
Guidance for petroleum titleholders on maintaining regulatory compliance when operational control changes. It explains continuing obligations under well operations management plans and environment plans, revised submissions, coordination with NOPSEMA and NOPTA, information access and transitional arrangements. It recommends aligning acceptance of revised plans with the transfer of operational control.
- 202631 Mar
Hazard identification and risk assessment guidance note
Guidance for titleholders on assessing well integrity risks throughout the well lifecycle. It discusses subsurface assessment, independent design review, qualitative and quantitative analysis, FMECA, bow-tie methods and risk registers. Risk profiles inform monitoring and maintenance regimes, anomaly management, change assessment, and planning for well suspension and abandonment.
- 202631 Mar
Source control planning and procedures information paper
This information paper sets out regulatory expectations for offshore loss-of-well-control preparedness across environment plans, well operations management plans and safety cases. It covers capping-stack selection and deployment, relief-well design and dynamic kill analysis, plume modelling, subsea dispersant supply, water-column monitoring, response-time modelling, coordinated operations and readiness exercises.
- 202631 Mar
Staged WOMP submission process
NOPSEMA describes its preferred phased submission of well operations management plans, separating lifecycle management processes from construction, production and abandonment detail. The paper explains concept-selection and detailed-design submissions, risk registers, barrier acceptance criteria, change management and regulatory inspections, while allowing titleholders to retain their existing submission structure.
- 202631 Mar
Well integrity control measures and performance standards guidance note
Guidance for developing and implementing well operation management plans addresses selection, assessment and assurance of well-integrity controls throughout the lifecycle. It explains links between risk assessment and measurable performance standards, periodic effectiveness reviews, functional testing, procedural assurance, contingency measures and relief-well planning, with quality checks for documented control performance.
- 2026Mar
Production PINCs
Numbered regulatory inspection questions address production safety systems, well barriers and casing-pressure diagnostics. Checks cover shutdown valve operation, gas and fire detection calibration, firewater pumps, pressure relief and protective devices on process equipment. Conditional approval requirements and specified testing intervals support inspection of production facilities and subsea components.
- 202627 Feb
Well status and surveillance definitions
This information paper standardises well-status and surveillance terminology for the Commonwealth petroleum and greenhouse gas storage industry. Drawing on international well-integrity standards, it distinguishes abandoned, suspended, shut-in and operational wells, defines boreholes and wells, and describes continuous barrier monitoring and visual inspection.
- 2026Jan
D-PINCs (Operators Version - Jan 2026) — Drilling
A regulatory checklist for oil and gas drilling, linking numbered compliance questions to statutory authorities and enforcement actions. It addresses approvals, diverter configuration and testing, casing installation, cement placement, drilling-fluid management and monitoring. Further checks cover ventilation, gas detection, ignition prevention and retention of drilling and test records.
- 2026Jan
Decommissioning
A regulatory checklist for temporary and permanent well abandonment under Subpart Q. Questions cover prior approval, isolation of open-hole zones and perforated intervals, cement plugging, conditional pressure testing, plug integrity, residual fluid density and wellhead removal. It also checks installation of two independent wellbore barriers, including a mechanical barrier.
- 2026Jan
Well Operations
An inspection guide presenting compliance questions for well operations under Subpart G, with regulatory authorities and enforcement codes. It covers casing and liner integrity, surface and subsea blowout preventer configuration, pressure and function testing, maintenance and records, alongside specific requirements for coiled tubing and snubbing systems.
- 2025May
Downhole Commingling Fact Sheet
This fact sheet explains downhole commingling in offshore oil production and BSEE’s increased pressure-differential allowance for deepwater Paleogene reservoirs. It outlines anticipated recovery benefits, crossflow risks, fluid compatibility and intelligent completions, alongside requirements for monitoring, surveillance and reporting and plans for further research.
- 202321 Nov
EI 158 Fatality Failure to Use Safety
An offshore worker died when surface casing failed during pressure testing supplied by a high-pressure well. The explosion involved pressure release without signs of ignition. BSEE identifies omitted pressure safeguards and deficiencies in planning and change management, and recommends operators consider equipment compatibility checks, gauge training and improved hazard assessment.
- 202123 Apr
Failed Seal on Subsea Safety Valve Causes Leak
A subsea safety-valve seal failure allowed hydrocarbons into hydraulic lines at a Gulf of Mexico production platform, releasing an estimated three to 50 barrels of hydraulic fluid and oil. The alert describes ROV sampling and leak isolation, and recommends considering hydraulic-system monitoring, alarm configuration and pressure management during leaks and platform evacuation.
- 20195 Dec
Safety Alert 371 - Conductor Failures Put Workers' Safety and the Environment at Risk
BSEE highlights well conductor failures observed during inspections and in industry incident reports. It describes internal corrosion associated with water and air entering the annulus, alongside inadequate structural support. Recommendations for operators to consider address water ingress, lateral support, cathodic protection and recurring ultrasonic or laser inspection for metal loss.
- 201819 Sep
Well Integrity (Operate Phase)
Inspection guidance for assessing well integrity during operation through management-system document review and role-specific interviews. It examines barrier verification, annulus pressures, operating and load limits, maintenance, change management and end-of-life review. Optional risk-assessment scrutiny covers qualitative assessment, QRA and FMECA, while enforcement guidance links inspection findings to compliance scoring.
- 20171 Oct
Well Examination Scheme - Issue 4
Inspection guidance for assessing well operators’ examination schemes across the well life cycle. It addresses documentary assurance, examiner independence and competence, management of changes, barrier verification and interfaces with installation verification. Interview material and success criteria support consistent recording of findings, compliance scoring and regulatory intervention planning.
- 20176 Jul
Well annulus leaks gas-lift inventory from failed instrument line
An instrument tubing failure released production-annulus hydrocarbon gas for 3.5 hours. Its position between the wellhead and gas-lift shutdown valve prevented shutdown from isolating the annulus inventory. The alert discusses small-bore integrity, secondary barrier vulnerability, two-barrier practice and recommended shutdown-valve placement and activation.
- 201628 Jun
Environmental Assessment
Final environmental assessment comparing regulatory alternatives for exploratory drilling in the Beaufort and Chukchi seas. It evaluates direct, indirect and cumulative effects of drilling-waste capture, well monitoring, source control, relief rigs and spill preparedness, balancing potential environmental benefits against additional operational disturbance and risks associated with more frequent BOP testing.
- 2015Dec
The Offshore Installations (Offshore Safety Directive) (Safety Case etc) Regulations 2015. Guidance on Regulations
HSE guidance explains the offshore safety-case regime for oil and gas installations in external waters. It covers submissions, acceptance, notifications, lifecycle reviews and transitional arrangements, alongside independent verification and well examination. Detailed guidance addresses major-accident risk evaluation, environmental protection, management systems, combined operations and emergency arrangements.
- 2015
Hydraulic Fracturing Primer 2015
An American Petroleum Institute overview presents hydraulic fracturing and horizontal drilling alongside their claimed energy and economic benefits. It explains well construction and stimulation, state and federal regulation, groundwater protection, water reuse, methane emissions and seismic monitoring, with examples of technologies intended to reduce environmental impacts.
- 2014Oct
guide to the health and safety regulatory regime
Guidance for planners explains HSE’s regulation of shale gas wells and its relationship with planning authorities and environmental regulators. It describes lifecycle well integrity, steel casing and cement, abandonment plugs, advance notifications, weekly reporting and independent well examination, alongside hydraulic fracturing consent requirements and routes for raising site concerns.
- 20145 Jun
Macondo Volume 1 Final Report
Volume 1 examines the Macondo blowout during temporary abandonment aboard Deepwater Horizon. It explains deepwater drilling, cement barriers, drilling-fluid pressure and positive and negative pressure tests. The report describes inadequate barrier assurance, separator overload and drillpipe buckling that inhibited BOP sealing, followed by explosions, fire and fatal injuries.
- 201217 Feb
Report - Montara investigation: Volume one
Volume one of an expert witness investigation into the Montara hydrocarbon release sets out the appointment, factual timeline and assessment framework. It examines well construction and suspension, cement isolation, barrier requirements, regulatory comparators and risk-management methods, introducing WAiT integrity assessment and documenting limitations in the supplied records.
- 201217 Feb
Report - Montara investigation: Volume three
Third volume of an expert witness investigation into the Montara hydrocarbon release. It reconstructs the operational timeline, charts H1-ST1 integrity during construction, suspension and re-entry, and evaluates barrier acceptance and verification. Technical responses examine corrosion caps, annular seals, cement isolation, change management and opportunities for risk assessment.
- 201217 Feb
Report - Montara investigation: Volume two
The second volume of an expert witness investigation examines nine issues surrounding the Montara hydrocarbon release. It assesses cement volumes, slurry properties, over-displacement, casing-shoe testing and corrosion-cap handling. Documentary analysis considers well suspension, barrier adequacy and programme changes, with proposed improvements to verification, contingency procedures and risk assessment.
- 2009Sep
A guide to the well aspects of the Offshore Installations and Wells (Design and Construction etc) Regulations 1996. Guidance on Regulations
Explains the well provisions of DCR 1996, covering life-cycle integrity, subsurface assessment, material suitability, well-control equipment and examination schemes. It addresses operator responsibilities, reporting and competence, including suspension and abandonment, and clarifies interfaces with offshore safety cases and installation verification across offshore and land-based operations.
- 200928 Jan
Safety Alert 275 - Wellhead Damage Caused by Hurricane
Following Hurricane Ike, damaged flanged wellhead connections leaked, and one subsurface safety valve initially failed to isolate downhole pressure. The alert examines hurricane loading and failed supports, and recommends visual inspection before restarting wells, followed by isolation, repair and wellhead pressure testing where excessive loading is suspected.
- 200812 Nov
Safety Alert 272 - Corroded Ring Gasket Causes Loss of Well Control
An MMS alert describes natural gas escaping through a corroded ring gasket during well scale-removal work. An inoperable subsurface safety valve prevented containment, and the platform was evacuated without injury. Acid treatment possibly accelerated gasket failure. Recommendations address acid-operation policies, emergency plans and gasket history or condition.
- 2008Nov
2008-054 Investigation of Loss of Well Control, South Pelto Block 10, Well No. 10, OCS-G02925, 14 February 2008, Gulf of Mexico off the Louisiana Coast..
Investigates natural-gas release during wireline scale removal and acid treatment at South Pelto Well No. 10. The panel identified ring-gasket corrosion, likely acceleration by acid treatment and an inoperable subsurface safety valve prolonging the event. It examines wellhead testing, integrity inspections and platform evacuation, recommending reviews of acid-operation policies and emergency plans.
- 20088 Oct
Safety Alert 269 - Loss of Well Control from Sustained Casing Pressure
An offshore well leaked gas at the mud line after earlier casing-pressure observations went unreported through required channels. Diagnostics suggested tubing-to-casing communication, but the investigation could not establish definitively how or why failure occurred. The alert recommends reviewing casing-pressure policies and clarifying reporting expectations in writing.
- 2008Oct
2008-053 Investigation of Blowout, Main Pass Block 91 Platform A, OCS-G14576, August 23, 2007, Gulf of Mexico, Off the Louisiana Coast.
Investigation of a gas blowout at Main Pass Block 91 Platform A, followed by platform subsidence. The report examines sustained casing pressure, poor cement quality, diagnostic testing and procedural communication failures. It describes unsuccessful kill attempts and relief-well abandonment, while leaving the precise casing-failure mechanism unresolved and recommending abandonment of remaining wells.
- 20051 May
Inadvertent Unlatching of Wellhead Connector
A semi-submersible inadvertently unlatched a subsea wellhead connector on a recently perforated well. Differential pressure separated the stack and broke the seal, allowing riser fluid levels to equalise with seawater pressure. Reduced hydrostatic pressure permitted crude oil influx; prompt relatching restored the seal and averted a catastrophic well-control and environmental situation.
- 200528 Jan
Safety Alert 226 - Pressure Rise to Surface after Cementing Leads to Burst Casing and Loss of Control
An offshore well lost control when worn surface casing burst following pressure migration from a previously pressure-charged shallow reservoir. Misleading hydraulic gauge readings concealed rising annulus pressure. The alert recommends examining logs and cementing coverage, checking rig alignment and casing-wear indicators, and routinely checking hydraulic gauges for full lines and leaks.
- 200429 Nov
Safety Alert 223 - Loss of Well Control
A workover involving nitrogen washing removed a sand bridge from a well shut in for approximately ten years. Gas escaped through a corroded wellhead injection port where a seal assembly was absent, causing a minor condensate spill. The alert recommends reviewing maintenance and improving written instructions and job safety analysis.
- 20038 Jan
Safety Alert 210 - Blowout After Cementing Surface Casing
An alert describes gas flow after surface casing cementing, increasing annulus pressure and subsequent gas emergence from adjacent wells. The platform was safely evacuated. Investigators identified probable cement-density regression and/or channel formation associated with delayed pumping. MMS recommends prompt cement pumping after landing casing and circulating at least one casing volume.
- 19953 Apr
Safety Alert 165 - Shallow Gas Flows While Cementing Surface Casing
This alert examines four shallow-gas incidents following surface-casing cementing, attributed to formation-fluid migration before cement developed compressive strength. It discusses diverter removal, annular flow and well-killing methods, and considers cement properties, location selection, back pressure and shut-in options. Laboratory testing is suggested as a better basis for determining cement waiting time.
- 197926 Dec
Safety Alert 92 - Testing of Subsurface Safety Valves
This alert describes occasional laboratory test failures of two sizes of tubing-retrievable, surface-controlled subsurface safety valves for high-flow-rate gas wells. Accumulated manufacturing tolerances caused internal parts to grab. It records tightened manufacturer specifications and case-by-case well reviews, and highlights the advisability of additional laboratory testing to verify operation against design.
- 19781 Dec
Safety Alert 81 - Blowout
A water injection well intersected a gas-lifted producing well during drilling, causing a blowout and platform evacuation. One roustabout sustained minor injuries, and the drilling rig suffered considerable damage. The alert describes directional surveys, interference plotting and monitoring drilling parameters to recognise and halt impending well interference.
- 19776 Dec
Safety Alert 69 - Blowout, Platform Loss
An offshore development well suffered a gas blowout during attempts to kill a deep saltwater flow. Gas jetting formed a seabed crater, undermining the platform legs; personnel evacuated safely before it toppled. The alert reviews drilling warning signs and planned casing-integrity checks, cement evaluation, well-control training and reassessment following operational deviations.
- 197726 Sep
Safety Alert 66 - Blowouts from Surface Casing, Conductor Casing Annulus
This alert describes delayed shallow gas flows between conductor and surface casing after cementing, sometimes requiring abandonment or vessel relocation. It attributes the flows tentatively to reduced cement-column hydrostatic head and outlines logging, casing movement, slurry selection, returns monitoring and conditional retention of blowout-preventer capability.
- Undated
Mixed-Fluid Release from a Subsea Well
BSEE investigates a mixed-fluid release from Shell’s PN003 subsea well at Mississippi Canyon 943. ROV diagnostics identified the leak, and valve closure and pressure testing restored two barriers. Tubing and control-line separation was suspected, pending recovery and analysis. The report records revised release estimates and planned tubing replacement.
- Undated
Well-Control Event and Hydrocarbon Spill During Coiled Tubing Work
BSEE investigates a well-control and pollution event at West Delta 80 D during coiled tubing work. The report examines tubing-to-casing communication, probable corrosion-related alignment pin plug failure, delayed remediation and reporting, and inadequate fluid-handling capacity. An estimated 107 gallons of hydrocarbons spilled; all 19 personnel evacuated without injury.
- Undated
Casing Weld Failure During Well Abandonment
Investigation of a casing weld failure during well abandonment. Reverse circulation following bit plugging led to casing rupture at recently welded seams. The report examines pressure testing, unchanged pump safety-device settings, inadequate job safety analysis and unapproved welding in place of cold cutting. No injuries or environmental spills occurred.
- Undated
Gas-Lift Tubing Rupture Injured Technicians During Casing-Valve Maintenance
Investigates injuries to two technicians during casing-valve maintenance on Main Pass 311 B. Unexpected casing pressure ruptured gas-lift tubing, knocking both workers down. Findings address misleading SCADA readings, unmonitored casing pressure, omitted diagnostics and pre-job checks, and discrepancies between installed equipment and approved drawings. Subsequent changes introduced direct pressure readings.
- Undated
Shallow Water Flow from Wellhead Cement Port During Riserless Drilling
BSEE investigates shallow water flow from a wellhead cement port during riserless drilling at Garden Banks Block 962. Fluid analysis detected limited hydrocarbons. Logging and ROV monitoring examined cement channelling; investigators identified salt contamination as the probable cause. Shell subsequently decided to temporarily abandon the well.
- Undated
Synthetic Drilling Mud Pollution Following Casing Installation and Cementing
BSEE investigates synthetic drilling-mud pollution at the Tiber #3 well in Keathley Canyon. The report traces casing installation, cementing, pressure tests and severe mud losses, identifying breakdown at the 22-inch casing shoe as the probable cause. It discusses possible contributing mechanisms, enforcement findings and a proposed district-notification condition for extreme losses.
- Undated
Loss of Well Control During Plug and Abandonment
BSEE investigates a well-control loss during plug and abandonment at West Delta 90 B. An estimated 20 barrels of well fluids escaped, followed by uncontrolled gas and evacuation. Findings identify a spooling-head breach, tubing communication and deficient use of historical well information; the precise origin of the tubing failure remains unresolved.
- Undated
Oil Release from Shut-In Subsea Well
BSEE investigates an oil release from Shell’s shut-in subsea VA007 well at Mississippi Canyon 940. ROV diagnostics and valve closures stopped the leak; subsequent e-line work identified parted production tubing at a coupling. The spill was estimated at seven barrels over several days. The reason for tubing failure remained unknown.
- Undated
Well Kick During Plugging Back for a Sidetrack
Investigation of a well-control event during plugging back for a sidetrack at Green Canyon Block 236. Packer leakage and embrittled elements were reported, with inadequate mud weight contributing. The kick was estimated at over 100 barrels; drilling mud arrived after roughly 30 hours and killed the well uneventfully.
- Undated
Subsea Gas Release During Hot Tapping for Well Abandonment
Investigates a subsea gas release during hot tapping for abandonment of a hurricane-toppled well. A diver inadvertently cut production tubing with a hydraulic hole-saw after concerns about cutting depth were overridden. The report examines supervision and stop-work failures, describes subsequent well-killing operations, and records no injuries or liquid hydrocarbon discharges.
- Undated
Gas and Oil Leakage from Well Released Oil into Gulf
Investigation of gas and oil leakage from Vermilion 279 well A3/A3D, with an estimated 0.67 gallons of oil entering Gulf of Mexico waters. The report traces earlier leak diagnostics and isolation attempts, attributing plug failure to reservoir shut-in pressure and describing deteriorated tubing and successive casing leaks.
- Undated
Loss of Well Control During Temporary Abandonment
Investigation of lost well control during temporary abandonment of the B002 well at Ship Shoal 225. Pulling a plug without checking pressure beneath it preceded hydrocarbon escape through leaking tubing and casings. The report examines deficient records review, testing, procedure changes, site-specific hazard analysis and supervision, and recommends stronger abandonment controls.
- Undated
Oil and Gas Release During Well Plug-and-Abandonment Work
Investigation of an oil and gas release during plug-and-abandonment work on well SS 204 A-13. The report attributes casing-patch failure to cyclic loading and excessive system weight, and describes a well kick with gas escaping through corrosion holes. Non-essential personnel were evacuated; no regional recommendations were made.
- Undated
Casing Rupture Released Hydrocarbons During Abandonment Remediation
BSEE investigates a casing rupture during abandonment remediation at Ship Shoal Block 114. Liftboat cranes and a hydraulic Vibro Hammer were used to straighten a damaged well. An estimated 56 gallons of hydrocarbons escaped into the Gulf of Mexico. The report describes personnel mustering, subsequent well stabilisation and installation of a pollution dome.
- Undated
Condensate and Gas Release Beneath Hurricane-Toppled Platform
Investigation of a condensate and gas release from Well C-9 beneath a platform toppled by Hurricane Ike. The report examines a broken master valve, uncertain subsurface barrier failures and a proposed trapped hydraulic-pressure mechanism. It describes limited condensate recovery, valve replacement and cement squeezing to secure the well.
- Undated
Well Toppled During Hurricane Isaac
Investigation of a well toppled during Hurricane Isaac at MP 116 beneath Ensco 81. Sonar identified the well resting on the seabed; failure appeared near a weld above the mud line. Findings discuss hurricane preparations, absent ultrasonic weld inspection and possible welding and drive-pipe design deficiencies. No recommendations were made.
- Undated
Shallow Gas Vented Between Conductor and Drive Pipe During Drilling
This investigation examines a drilling incident involving apparent conductor-casing cement sheath failure and shallow gas venting between the conductor and drive pipe. Possible contributors include slurry contamination, gas migration, thermal expansion and mechanical vibration. The report records no personnel injuries or pollution of Gulf waters.
- Undated
Gas Release and Surface Casing Collapse During Well Abandonment
BSEE investigates a gas release during well abandonment on South Marsh Island Block 281C. Corrosion and loss of conductor casing led to surface casing collapse at Well C-11, damaging valves and decking. The report describes evacuation, well securing and subsequent abandonment, and records noncompliance with immediate incident-notification requirements.
- Undated
Casing Leak Released Oil and Gas into Sea
BSEE investigates a casing leak at South Pass 28 13(V) that released oil and gas into Gulf of Mexico waters. The report traces unsuccessful well-killing attempts, bridge-plug isolation and welded repair. It identifies inadequate preventive maintenance, corrosion and erosion as probable causes, alongside rough seas and shallow water as contributing conditions.
- Undated
Hydrocarbon Release During Casing Cutting for Subsea Well Abandonment
Investigation of hydrocarbon leakage during abandonment of a temporarily abandoned subsea well in the Gulf of Mexico. Cutting casing strings released trapped annular gas and liquid hydrocarbons. The report describes spill response, a pollution dome, remedial cement plugging and subsequent clearance, and identifies primary casing cement as the only annular barriers.
- Undated
Vessel Lost Station Keeping and Severed Production Tree During Wireline Operations
Investigation of Endurance’s loss of station keeping during wireline operations at Eugene Island 355A. Vessel movement severed the production tree through connected rigid pipework, causing an oil spill and deck damage without reported injuries. Suspected communications-tower interference and absent emergency disconnection are examined, alongside equipment-separation measures and proposed vessel evaluation procedures.
- Undated
Vessel Collision Sheared Wellhead and Ruptured Gas Lift Line
An unidentified vessel struck Chevron’s satellite well structure No. 138, shearing the wellhead and rupturing a gas lift line. Dry gas escaped, with no injuries or pollution reported. The investigation attributed the collision probably to loss of vessel control; weather and navigational-aid performance remained undetermined.
- Undated
Two Drilling Kicks During Deepwater Well Operations
Investigation of two drilling kicks on Maersk Valiant in Walker Ridge Block 578. The first discharged approximately 55 barrels of mud onto the rig floor; shut-in fractured the formation and casing shoe. ROV checks and wireline logs assessed containment. The second kick remained contained. Neither incident caused injuries or pollution.
- Undated
Wellhead Gas Leaks During Production Restoration After Hurricane
Investigation of wellhead gas leaks during restoration of platform production after Hurricane Ike. Stretched flange studs compromised seals, while Well G-4’s SCSSV initially failed to seal. The report describes flaring, component replacement and testing, and recommends post-event inspections, isolation and wellhead pressure tests before reopening SCSSVs.
- Undated
Casing Failure Released Drilling Mud During Deepwater Well Operations
This investigation examines casing failure and drilling-mud pollution during deepwater well operations. Drill-pipe wear at a buckled liner connection caused leakage, with synthetic-base mud reaching the seabed. It describes diagnostic logging, cement plugging and leak squeezing, alongside proposed improvements to casing design, wear monitoring, change management and engineering training.
- Undated
Condensate Release During Plug and Abandonment and Salvage Operations
Investigation of a condensate pollution event during plug and abandonment and salvage operations at Grand Isle Block 47. The report attributes the release to wellhead mechanical failure, rather than the initially reported impact. It records containment attempts, wellhead installation and testing, subsequent annulus leakage, and differing spill-volume estimates.
- Undated
Ejected Master Valve Stem Injures Contractor During Temporary Well Abandonment
Investigation of a manual master valve failure during temporary well abandonment at EI 252-G. An ejected valve stem struck a contractor’s hand, fracturing his thumb tip. Personnel were evacuated because well stability was unknown. Findings address a missing retainer nut, valve servicing, contractor oversight and management of change.
- Undated
Drilling Mud Released to Seafloor Following Casing Disconnection
This investigation examines synthetic-base drilling mud losses during diagnostic and well-abandonment operations in the Gulf of Mexico. Casing disconnection released mud to the seafloor. The report identifies inadequate casing make-up torque and poor surface-casing cementing as probable causes, and records recommendations concerning torque, cement volume, rig heading changes and connector design.
- Undated
Gas Leakage from Master-Valve Flange During Platform Renovation
An investigation examines gas leakage from a well’s master-valve flange during platform renovation. Findings suggest installation over-torque weakened two bolts, with high-sea motion believed to contribute to failure. A closed subsurface safety valve limited the release. Personnel evacuated by boat before specialist repairs; no injuries or pollution were reported.
- Undated
Oil Release from Permanently Abandoned Subsea Well
Investigation of an oil release from a permanently abandoned subsea well in the Gulf of Mexico examines drilling, cement placement, plug verification and delayed well-control response. The specific cause remained unresolved because deeper plugs could not be reached. Findings identify possible contributing factors and propose research and regulatory changes.
- Undated
2023-004 158 Investigation of May 15, 2021, Fatality
BSEE investigates a fatal casing pressure test on Eugene Island Block 158’s platform. Gas supplied from an adjacent well without pressure regulation or a pressure safety valve overpressurised the casing. The report examines incomplete job safety analysis, absent management of change and possible confusion between gauge display units.
- Undated
Engineered Safety and Environmental Aspects of Well Construction and Fracturing Design
Presentation on engineering well construction and hydraulic fracturing for pressure containment and groundwater protection. It covers casing and liner design, cement evaluation, treating-line ratings and testing, staged pump shutdowns, relief arrangements and wellhead valves. Surface planning addresses fluid storage, spill berms and logistics, alongside examples of fracturing-fluid ingredients.
- Undated
Environmental Regulation and Planning Conditions for Onshore Oil and Gas well sites in the UK
Presentation outlining environmental regulation and planning approval for UK onshore oil and gas wells. It addresses surface pollution, well design and hydraulic fracturing risks, extractive waste permits, waste management plans and monitoring after decommissioning. It also explains regulator coordination, protected areas and local planning conditions.
- Undated
Equinor - Deepsea Bollsta - investigation of well control incident
Investigation of a gas release during permanent well abandonment on Deepsea Bollsta at Troll. Casing cutting released reservoir gas behind the casing, causing minor injury to one person and equipment damage. The report examines cement barriers, ultrasonic logging interpretation, BOP operation, gas detection, ventilation pressures and escape difficulties.
- Undated
Health and Safety Regulatory Regime in the UK
HSE presentation explaining regulation of onshore oil and gas through well notification, independent examination, safety documentation, operational reporting and enforcement. It follows well integrity from design to abandonment, including cement barriers and verification methods, and outlines safeguards for hydraulic fracturing and protection against respirable crystalline silica exposure.
- Undated
Hydraulic Fracturing and Onshore Oil and Natural Gas Development - Industry Standards for Safe and Responsible Development
Erik Milito’s presentation outlines API standards and regulatory frameworks for onshore oil and gas development, including hydraulic fracturing. It discusses groundwater protection through well construction, environmental management, chemical disclosure and community engagement, alongside occupational safety standards and hydrocarbon vapour hazards when opening storage-tank hatches.
- Undated
ND Regulations, Planning and Permissions
Presentation explaining hydraulic fracturing technology and North Dakota regulation across the well lifecycle. It examines water supply sustainability, geological confinement, well construction, chemical disclosure and flowback management. Specific measures include cemented casing strings, pressure testing, witnessed well plugging, restrictions on open-pit storage and permitted underground disposal.
- Undated
Statoil - Visund - Investigation of well-control incident
Investigation of a well kick during washing at Visund A examines liner-barrier verification, BOP configuration and jammed kelly cock valves that obstructed conventional well killing. Control was restored after the valves opened. Findings address maintenance, risk assessment and exercises; direct and underlying causes remained uncertain.
- Undated
Waste Water Disposal and Abandonment Philosophy
This presentation outlines saltwater disposal challenges, chemical and operational treatments, and monitoring of corrosion, scale and injection economics. It explains fluid migration risks from abandoned wells and North Dakota cementing methods, including low-pressure squeeze and balanced plugs, with preparation steps and typical Bakken and Three Forks isolation arrangements.
- Undated
working together agreement of the shale regulator group
A non-binding agreement between the Environment Agency, HSE and Oil and Gas Authority sets out coordinated regulation of shale gas developments. It describes operator coordinators, joint inspections where appropriate, assistance to planning authorities and public engagement, while preserving each regulator’s independent powers. An advisory steering group oversees cooperation.
- Undated
Working together agreement on regulating unconventional oil and gas developments
Joint Environment Agency and HSE statement sets out coordinated regulation of unconventional oil and gas developments, focusing on shale gas. It describes environmental permitting, well-design assessment, weekly construction reports and joint inspections of hydraulic fracturing operations. A November 2014 review retained the agreement without changes.