Continual improvement of international well integrity standards

Article published in the Regulator | Issue 2: 2017 

Adopting and applying relevant standards and guidelines is an integral part of a regulator’s toolbox when assessing and inspecting a titleholder’s capability to effectively carry out their well operations. This includes well design, well construction, production, testing, well intervention, suspension and abandonment operations. Whether a regulator administers a prescriptive or non-prescriptive regulatory regime, the standards and guidelines used are tools which help identify if a titleholder is adhering to good industry practice.

Following the Macondo and Montara blowouts in 2009 and 2010, API, ISO, NORSOK, Oil and Gas UK and other bodies have developed and updated standards and guidelines specifically for well integrity in an effort to avoid repeating the costly mistakes of the past. The International Regulators Forum (IRF), of which NOPSEMA is a member, accepts the following as good industry practice:

  • ISO 16530 Well Integrity — Part 1: Life Cycle Governance

  • ISO 16530 Well Integrity — Part 2: Well Integrity for the Operational Phase

  • NORSOK Standard D-010 — Well Integrity in Drilling and Well Operations

  • Oil & Gas UK Well Integrity Life Cycle Guidelines

  • Oil & Gas UK Guidelines for the Abandonment of Wells

  • Oil & Gas UK Guidelines for Qualification of Materials for the Abandonment of Wells.

There are approximately 250 specific well integrity related standards and guidelines that fall under the international standards, written by various standards bodies. The standards and guidelines pertaining to well integrity can be split into the following categories:

  • general guidance — hazards, risks and personnel competencies and technical guidelines such as the management of safety-critical elements and well control operations

  • equipment standards

  • testing standards for materials and equipment

  • high pressure high temperature standards and guidelines

  • drilling and completion fluids standards

  • cementing and cementing equipment standards.

The ongoing challenge for industry is to ensure continual identification of gaps in the standards and guidelines they choose to adopt. NOPSEMA, in collaboration with its international counterparts in the IRF, has identified the following potential gaps to assist industry in this task:

guidance on monitoring of well indicators during drilling such as real-time pore pressure prediction and finger printing on connections and gas indicators

guidance on how sub-surface personnel perform pore pressure fracture gradient predictive work

  • standardisation between various international guidance documents for placement and length of cement plugs

  • guidance on cementing operations, such as cement placement and acceptance criteria for cement jobs 

Well barriers

  • standards for shoe-track as a barrier — consider qualifying float equipment as a barrier

  • surface controlled sub-surface safety valves — guidance on the different statuses such as safety-critical, primary barrier or emergency only

  • guidance on when it is appropriate to use storm chokes

  • quality control of connector bolts (refer to BSEE Quality Control-Failure Incident Team findings)

  • guidance on risk assessment of wells with sub-hydrostatic reservoirs (barrier requirements)

Suspension and abandonment

  • standardised definition is required for shut-in, suspension, temporary suspension, temporary abandonment and abandonment

  • recommended duration of suspension and temporary abandonment periods such as risk of degradation of metallic and elastomeric barriers

  • clearer recommendations on monitoring and inspection of long-term suspended or temporarily abandoned wells

  • guidance on using geological formations as abandonment barriers (based on the Norway/UK/GoM model)

  • standards for epoxy resin plugs to be used as suspension or abandonment plugs

  • more guidance on abandonment with tubing and completion jewellery in place such as adhesion of cement to oil wet tubulars, placement methods of cement barriers using small volumes

It is important for industry to be aware of their duty to continually identify and address any gaps in the existing standards and guidelines in order to manage well integrity risks to as low as reasonably practicable. NOPSEMA encourages industry to assist standards bodies to address the gaps listed above to ensure they continue to understand, demonstrate and apply current good industry practice.