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 "diagnostic_note": "Windows <=3 m are at raster-noise scale (1-sigma raster noise alone is roughly +/-7 pp at 2 m and +/-5 pp at 3 m on a 1 m DTM). Diagnostic use only: never a headline or ranking value.",
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  "calculated_at": "2026-08-24T20:55:37+00:00",
  "road_source": "OpenStreetMap (local PBF extract)",
  "road_attribution": "\u00a9 OpenStreetMap contributors, ODbL",
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  "osm_snapshot": "2026-08-21T20:21:11Z",
  "run_id": "redo-nh-1-260824",
  "elevation_provider": "USGS 3DEP (The National Map)",
  "elevation_licence": "Public domain \u2014 USGS 3DEP 1 m DEM, courtesy of the U.S. Geological Survey",
  "elevation_dataset": "USGS 3DEP 1 m DEM, NH_Umbagog_LiDAR_2016_D16 (collected 2016)",
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  "notes": "Coarse pass: max 13.4% over 200 m (Terrain 50), gain 142.4 m over 2672 m way. EXTENDED by graph walk: +0 segment(s) at base, +5 at top (stop: base=no_descending_continuation, top=no_ascending_continuation; min_avg=2.0%). Review before adopting. DEDUPE: absorbed 5 overlapping proposal(s): black-mountain-road, black-mountain-road, discovered-lane-44-1700-71-1582, east-field-road, moody-farm-road ADOPTED (NE wave 1, 2026-08-25): big-gain. Wales dials per PRODUCTION 'US ADOPTION DIALS'.",
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   "ept_source": "https://s3-us-west-2.amazonaws.com/usgs-lidar-public/NH_Umbagog_2016",
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  "license": "ODbL-1.0",
  "license_url": "https://howsteep.org/licensing.html"
 },
 "area": {
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  "county": "New Hampshire"
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}