Evidence checked 5 September 2026. This is a station-context review; no concentrations were calculated, screened, attributed, or selected as background.
Finding: E304570 / NAPS 101603 is a documented town exposure station, with a nominal 4 m inlet above ground. It is a useful candidate observation record for Squamish receptors. The recovered metadata do not establish a spatially uniform background for the project site, the fjord, or a 20 × 20 km domain. The decisive remaining evidence is dated site/instrument history and a comparison of the meteorological and emissions regimes experienced by the monitor and intended receptors.
| Item | Evidence and interpretation |
|---|---|
| Identity and location | Provincial metadata link E304570 to NAPS 101603 at 38370 Buckley Avenue, 49.70516, −123.15133, elevation 6 m. Owner is recorded as ENV. The _15 and _60 metadata aliases share the ID and coordinates and describe the position as next to the school playing field; they are not evidence of three physical sites. BC station metadata. |
| Inlet and clock | NAPS lists 4 m above ground and UTC−8. Its definition applies the listed inlet height to all pollutants unless otherwise specified. This is one metadata entry, not an installation or modification history. NAPS workbook, Stations2024 row 529; Definitions_Définitions!B16. |
| Monitoring purpose | Codes decode to PE: general population exposure, SU: small urban area, P3: neighbourhood population 10,000–49,999, C: commercial land use, N: neighbourhood scale. “SU” does not mean suburban. Commercial means the dominant category within 400 m. The neighbourhood scale describes roughly 0.5–4 km with relatively uniform land use; it does not delineate a validated circle. The site is classified PE rather than regional background (RB). This classification does not prove absence of traffic or point-source influence. NAPS workbook, definitions B39–B40, B46, B48–B51, B55–B57, B64–B67. |
| Metadata vintage | The NAPS workbook sheet is Stations2024; its file modification date is 25 June 2026, while the companion CSV was modified 9 July 2026. The workbook identifies 2021 census inputs for classifications. BC metadata downloaded from the 2023, 2024 and 2025 folders are byte-identical files with August 2026 modification dates. These are not three independent historical snapshots. See preserved directory metadata and reused-source-manifest.json. |
The NAPS list links Elementary with former NAPS 101601, Squamish Government Building, at 38075 2nd Avenue, 49.700098, −123.154216, elevation 20 m. The workbook defines such combinations as moved sites whose observations may be joined for trend analysis, after provincial/territorial consideration of site characteristics. That is not approval to substitute one location for another as dispersion background. NAPS workbook, rows 528–529 and definition B15.
Dates differ by record: NAPS gives Elementary start 15 December 2015, while BC metadata and the provincial AQHI review give 17 December 2015. NAPS gives Government Building end 31 December 2015; the AQHI review's observation period extends to 6 February 2016. Its Elementary period ends at the review's 2020 cutoff, not a station closure. Preserve these source-specific dates pending the relocation/parameter history; different program scopes may contribute to the discrepancy but have not been reconciled. 2022 AQHI review, Table A.1, printed p. 31 / PDF p. 49.
The preserved provincial hourly records use the same model labels throughout 2023–2025: PM25_SHARP5030i, NOX_TEI42i for NO/NO₂/NOx, O3_APIT400, and SO2_APIT100U. Labels identify a model family, not serial numbers, firmware, settings, replacements or successful audits. The native yearly files and their acquisition manifests remain under work/ambient-baseline/.
| Archive label | Primary method evidence | Still needed for 2023–2025 |
|---|---|---|
| SHARP5030i | Integrated nephelometry and beta attenuation; the BC SOP discusses moisture control, inlet losses, hybrid operation and maintenance. BC Field Sampling Manual, Part B1, Appendix 2, printed pp. 74–77 / PDF pp. 77–80. | Installed size selector, actual heating/RH settings, flow/leak checks, optical/mass checks and changes. Generic SOP settings are not confirmed station settings. |
| TEI42i | Chemiluminescence; the manufacturer lists molybdenum and stainless-steel converter options. 42i datasheet, March 2026, pp. 1–2. | Installed converter, efficiency checks, sampling path, interference treatment, calibration/change history. The model label does not identify the converter. |
| API T400 | UV absorption. Manufacturer T400 sheet, p. 1. | Installed configuration, inlet path, maintenance and calibration history. |
| API T100U | UV fluorescence. Manufacturer product description. | Installed configuration, zero/span history, calibration and validation history. |
The archive README describes the annual data as QA/QC validated, except folders marked _Unverified. RAW_VALUE therefore means full-precision values within the verified archive, not an unverified live feed. The native schema does not expose per-record validation flags or reasons for missingness. Generic BC requirements cover calibration documentation, progressive validation and audits; their existence is not proof that particular station checks passed. Provider README; Field Sampling Manual, Part B1 §§6.6–7.3 and §11, printed pp. 23–28, 39–40.
There is a direct project-specific warning against relying solely on the town monitor: Health Canada's 28 November 2022 comment described Elementary as approximately 8 km from the project and recommended onsite NO₂ and PM₂.₅ monitoring near worker accommodation to verify predictions and establish pre-construction conditions. Woodfibre's 14 February 2023 response committed to floatel monitoring. This documents a reason for local verification, not a measured concentration gradient or attribution of any town event. EAO Floatel TAC record, p. 66.
One specific nearby-activity lead was located: the school's March 2025 newsletter announced playground swing construction over spring break. This does not establish actual work dates, equipment, inlet proximity, dust, or an effect on measurements. School newsletter, “SQE Playground!”. Traffic, shipping, construction and regional smoke contributions remain hypotheses unless supported by contemporaneous source and meteorological evidence. No peak attribution is made here.
BC's July 2026 guideline requires attention to meteorology, terrain, surface characteristics, emissions and changes when using another location. It also warns that ozone used for plume chemistry may be depleted by local NOx. Consequently, the suitability of Elementary PM₂.₅ background and its ozone chemistry input are separate questions. BC dispersion guideline, §§8.1–8.2, printed pp. 70–75 / PDF pp. 77–82.
These are acquisition priorities, not requests sent. Detailed fields, sources and acceptance gates are in evidence-and-gaps.json.
Reviewed the existing BC annual-archive metadata/README, current NAPS station catalogue and its official workbook definitions, BC AQHI network review, BC field and dispersion guidance, primary manufacturer records, the EAO floatel comment record, the BC live station page and the school newsletter. Original successful downloads, URLs, UTC retrieval times, sizes, hashes and HTTP metadata are retained in sources/acquisition-manifest.json; reused files are hashed in reused-source-manifest.json. The two decisive PDF pages were visually checked and retained as sources/aqhi-table-a1.png and sources/tac-pdf66.png. The NAPS CSV/workbook and directory listing are complete original downloads; station-metadata-evidence.json preserves exact target rows and definition cells.
The catalogue's public API provided downloads after its page returned a JavaScript shell. Stable API entry URLs are cited above. For public reuse, use acquisition-manifest-sanitized.json: it retains stable URLs, timestamps, status, sizes and hashes while removing temporary signed-download queries and cookie headers. The raw fetch manifest remains unchanged in work. All 12 successful original downloads were rechecked against their recorded sizes and hashes; results are in provenance-verification.json.
Several Thermo documents returned 403, and one guessed Teledyne specification path returned 404; failures are recorded, not treated as unavailable records generally. The successful BC SOP supplies the PM method evidence. No dated station-specific inlet changes, audit log, equipment serial history or completed source-attribution study was located in this bounded review. That is a search result, not a claim that such records do not exist.