Design constraints of a closure design basis and cover options assessment for a gold mine tailings facility in the Canadian Shield
Bibliographic record
Abstract
A design basis was developed to guide closure design decisions for a tailings facility at an operating underground gold mine in the Canadian Shield of Ontario, Canada. An interdisciplinary design team made up of subject matter experts in geotechnical engineering, groundwater and surface water hydrology, geochemistry and ecology collaborated with site personnel through a series of workshops to develop the design basis, which was subsequently used to inform a structured screening-level options assessment for alternate closure cover scenarios. Various end land uses were considered in developing the design basis, which resulted in 19 site-specific closure goals organised within six overarching focus areas: 1) geotechnical performance; 2) geochemical performance; 3) surface water; 4) groundwater; 5) land use and ecology; and 6) earthworks, landform design and active care. Design constraints identified in the design basis included a limited appetite for disturbing new areas for borrow material, a preference for a dry landform, and the desire to limit net percolation in a humid continental climate, lower groundwater levels in the tailings and curtail degradation of groundwater quality. Regulatory guidelines, the expectations of local communities and First Nations people, economic feasibility and land capability were also recognised as potential constraints. A range of conceptual cover designs were developed within the identified constraints, incorporating modelling of projected post-closure ecosystems. A qualitative options assessment framework was used to provide relative rating of the cover options based on their technical merits in relation to the design goals set out in the closure design basis. The screening-level options assessment highlighted the need for the closure design to balance the potentially competing demands of a low-permeability cover system with the desire to minimise land disturbance and use of borrow materials.
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 | 0.009 | 0.008 |
| Meta-epidemiology (narrow) | 0.001 | 0.001 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| Bibliometrics | 0.002 | 0.001 |
| Science and technology studies | 0.003 | 0.002 |
| Scholarly communication | 0.003 | 0.001 |
| Open science | 0.002 | 0.002 |
| Research integrity | 0.002 | 0.001 |
| Insufficient payload (model declined to judge) | 0.005 | 0.001 |
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".