Grouting Techniques Used to Decommission a Flowing Artesian Well
Bibliographic record
Abstract
In 1965, during drilling of an investigative borehole located on the Coldstream Ranch lands in the interior of British Columbia, Canada, a previously undiscovered, strongly flowing artesian aquifer was encountered at approximately 61 m below ground surface. The encounter resulted in a blowout that compromised the two overlying aquitards, referred to as the Upper and Lower Aquitards, and was followed by several attempts to plug or contain the uncontrolled flow of approximately 38 L/s. These attempts resulted in the final well configuration of the coldstream ranch well (CRW): a nominal 16-inch casing with a telescopic screen at a depth of about 52.7 m surrounded by a nominal 30-inch open-ended casing pile driven to a depth of 44.5 m. The low-strength Upper Aquitard overlain by the upper (surficial) Unconfined Aquifer was washed out during the initial blowout and the installation of the 30-inch casing, which resulted in a large surface crater and consequent loss of materials and drilling equipment. The connection to the flowing Lower Aquifer is inferred to have been by a large “breach” in the competent Lower Aquitard, infilled with winnowed sand and gravel from the Lower Aquifer. In 2013, a large diameter, high-flow relief well was installed adjacent to the CRW to assist in lowering the piezometric surface of the Lower Aquifer as part of a new decommissioning attempt. Due to the potentially high aquifer pressures relative to the depth of the relief well, it was designed and constructed using three telescoping casings, grouted in place using oilfield methods. Following relief well installation and prior to plugging of the CRW, the near surface soils surrounding the CRW required improvement and stabilization to develop an adequate seal around the 30-inch surface casing that was to remain in place. Compaction grouting was conducted in two concentric, offset ring patterns to consolidate and stabilize the Upper Aquitard and Unconfined Aquifer. To plug the CRW and stop the associated flow, the 16-inch casing and screen were pulled and the permeable sediment filling the Lower Aquitard breach was drilled out. Thereafter, the hole was sealed by injecting low mobility grout from the Lower Aquifer up through the Lower Aquitard, across part of the Middle Aquifer, and into the base of the 30-inch casing. The final step of decommissioning the CRW was perforation of the 30-inch casing and backfilling the casing and its annulus with a flowable grout to fill any voids between the casing and the formation. This paper describes the techniques used to install the relief well, including telescoping casing, as well as the various grouting methods used to successfully plug the CRW, resulting in a final shut-in pressure of 340 kPa at the RW3 wellhead.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.001 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.002 | 0.001 |
| Science and technology studies | 0.001 | 0.001 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.000 | 0.001 |
| Insufficient payload (model declined to judge) | 0.008 | 0.003 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".