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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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  "elevation_dataset": "USGS 3DEP 1 m DEM, VT_Statewide_A23 (collected 2023)",
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  "notes": "Coarse pass: max 15.8% over 200 m (Terrain 50), gain 61.9 m over 635 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'.",
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  "license": "ODbL-1.0",
  "license_url": "https://howsteep.org/licensing.html"
 },
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}