Identification and Monitoring of Safety Critical Activities in Drilling New Wells while concurrently Producing Existing Ones in OML 26 (Onshore Nigeria)


When NPDC and FHN joint venture partners proposed to drill five wells in existing wells pad with two producing wells, it needed help in understanding the health, safety and environment implications. This Simultaneous Operation (SIMOPS) which involved producing one gas lifted well, drilling new ones and tying them in to increase production has some safety components that required critical review.

The Ogini simultaneous production and Drilling Campaign which is within OML 26 is located about 63 km east of the town of Warri, Delta State, onshore Nigeria.

Our Approach

A multi-disciplinary team/ committee comprising of some experienced client staff and Kogzytech Associates Limited (KAL) consultants were instituted- to evaluate the simultaneous operations (SIMOPS) more critically and come up with a safety case for these operations.

An Opportunity Framing Workshop was used to identify Five Key Modules and Elements, which led to the generation of a HAZARD Identification Sheet for the drilling campaign SIMOPS. On completion, the HAZARD Identification table was ranked using a Risk Assessment Matrix (RAM) and finally progressed to a hazard/risk register for the campaign.

The identified modules and elements for this unique exercise were:

  1. Drilling and camp-site preparations
  2. Interface between the flowline and the well
  3. Well delivery and production during drilling
  4. Rig move (in and out)
  5. Flowline constructions

All risks associated with various activities from drilling, flowlines design, engineering, construction and continuous production were completely assessed and controls as well as related remedial action plans were put in place to reduce risk to as low as reasonably practicable while profitability is not sacrificed.

Benefits and Value

By working with KAL to conduct a thorough assessment of risk and related hazards, NPDC/FHN was able to:

  • Identify and manage all associated HSE challenges in concurrent drilling and production operations during the campaign.
  • Five new wells were successfully drilled and are presently flowing with the existing wells on that same well pad.

Recommended HSE management and monitoring systems for operating multi-well location onshore are used to support activities in that field.