Diavik Waste Rock Project: Post-emplacement investigation of sulfide weathering from a deconstructed experimental waste-rock pile
Bibliographic record
Abstract
Deconstruction of a 15 m high low-sulfide (0.035 wt% S) experimental waste-rock pile was conducted to obtain a dense, spatially located sample set for characterization of the solid-phase mineralogy, microbiological community composition, and pore-water geochemistry. The experimental test pile, located in northern Canada, was deconstructed 8 years after construction. Pore-water with low pH was generally associated with elevated concentrations of SO 4 and dissolved metals. Regions of differing pH were present within the test pile, indicating heterogeneous distribution of sulfide and carbonate minerals. Most probable number analysis showed that neutrophilic sulfur oxidizing bacteria were the most consistently prolific of populations associated with acid mine drainage at the time of deconstruction. The mineralogical evolution was examined through comparison of unweathered samples collected at the time of pile construction to weathered samples collected during the deconstruction phase. This analysis indicated that the C content of the waste rock was depleted, but the total S content of the waste rock remained relatively unchanged. Neutralization potential ratios calculated using C and total S indicate that regions of low paste pH (as low as 4.0) were generally consistent with the presence of material classified as potentially acid generating or of uncertain acid generating potential. The deconstruction study shows that variable conditions exist within the test pile (e.g., sharp changes in pH over a few meters) suggesting that waste-rock heterogeneity has influenced the geochemical evolution of the pore water within the test pile. • Deconstruction of a 15 m low-sulfide experimental waste-rock pile conducted to obtain a dense, spatially located sample set. • Heterogeneity in mineralogical distribution influenced the geochemical evolution of the pore water within the test pile. • Comparison of total S and sulfide S indicates the importance of considering S source in acid-base accounting. • The greater reactivity of finer particle-size fractions necessitates their consideration in waste rock characterization.
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 distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
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 teacher head, 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".