Surface · Abandonment
Cut & Cap Below Grade
The final step at surface: the casing strings are cut below the ground and closed with a steel plate, then buried.
What it does
Leaves nothing at surface that can be hit by farm equipment and keeps access closed. In Alberta it must happen within 12 months of the downhole abandonment and only after the tests show no well problems.
Basics
| Cut depth | At least 1 m below final ground level |
| Deeper cut | 2 m on deep tillage or peat land, or within 15 km of urban areas |
| Cap | Fastened steel plate that prevents pressure buildup |
| Timing | Within 12 months of downhole abandonment |
| Rules | AER Directive 020, section 8 |
Common failures
- Capping a well that still has vent flow or gas migration
Troubleshooting
- Symptom
- Pressure or gas found at the plate later
- Likely cause
- Leak not repaired before capping
- What to check
- Re-enter, find the source and re-abandon