Well intervention and production improvement project.
- Well engineering & operations
- Expert technical advice
- Project delivery
Lochard Energy manages the Iona gas storage and production complex in the Otway Basin. The North Paaratte 5 well is part of the North Paaratte Gas Field, which forms part of the Iona gas storage complex. The well was drilled in 1999 and is used for both production and injection within the overall gas storage project. The well had been experiencing subsurface issues that was limiting its injection capability. We were engaged to design and execute a well intervention project in 2019.
We designed a well intervention program to resolve historical issues of a solid, brown sticky substance across the perforations that limited the injection capacity of the well. The scope included the engagement of various service companies to carry out the program of work over a number of weeks.
The high-level sequence we designed and executed included:
- High pressure jetting of the formation at the perforations area, cleaning up across the perforations and the cleaning out of the lower perforations and rat hole. The jetting was assisted by gel sweeps, designed to lift any suspended particles that may still be in the cased hole section and raise them to the surface.
- Coiled tubing clean-out, breaking up residual solids and providing velocity to lift and unload the solids.
- The coil tubing unit was used again to unload the well of liquids using nitrogen injection, then the well was flowed to flare to finalise the well clean-up.
- At the conclusion of the clean-out and flow-back, wireline ran in the hole and reperforated the affected interval.
The intervention was a technical success, with no HSE issues reported during what was a complex and changing operational phase. Upfront project planning to define the project objectives was a key factor in achieving the project’s objective. The months of planning we undertook in the lead-up to mobilisation made the implementation of the planned work considerably more efficient. Many potential issues were predicted and equipment requirements covered, so despite poor weather and deteriorating site conditions, the project was able to stay consistent with predicted timelines.