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  "road_source": "OpenStreetMap (local PBF extract)",
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  "elevation_provider": "USGS 3DEP (The National Map)",
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  "notes": "Coarse pass: max 15.8% over 200 m (Terrain 50), gain 41.3 m over 338 m way. KEPT at seed extent: no ascending continuation (min_avg=2.0%). ADOPTED (NE wave 1, 2026-08-25): clean-steep. Wales dials per PRODUCTION 'US ADOPTION DIALS'.",
  "canopy_check": "unavailable \u2014 no surface model (DSM or point cloud) registered for this coverage",
  "license": "ODbL-1.0",
  "license_url": "https://howsteep.org/licensing.html"
 },
 "area": {
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  "county": "New Hampshire"
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}