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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, RI_Statewide_D22 (collected 2022)",
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  "notes": "Coarse pass: max 8.5% over 200 m (Terrain 50), gain 68.4 m over 4153 m way. EXTENDED by graph walk: +0 segment(s) at base, +2 at top (stop: base=no_descending_continuation, top=no_ascending_continuation; min_avg=2.0%). Review before adopting. ADOPTED (NE wave 1, 2026-08-25): big-gain. 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": "Rhode Island"
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}