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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": "2026-08-25T05:29:21+00:00",
  "road_source": "../ne-docs/ma/hessian-lane/hessian-lane.geojson",
  "run_id": "rebatch-manifest-ma-fix-260825",
  "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, MA_Western_B24 (collected 2023-24)",
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  "notes": "NE box session: masked re-batch, NHD flowline-crossing evidence per ne-vdip-mask-manifest.csv (2026-08-25). ADOPTED (NE wave 1, 2026-08-25): clean-steep,qualified-steep. Wales dials per PRODUCTION 'US ADOPTION DIALS'. MASKED RE-BATCH (2026-08-25): culvert-class V-dip masks applied (NHD flowline / xsection channel-crossing evidence, ne-adoption-audits); superseded values in B2 redo trees.",
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  "license": "ODbL-1.0",
  "license_url": "https://howsteep.org/licensing.html"
 },
 "area": {
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  "county": "Massachusetts"
 }
}