{
  "site_name": "Springhill Regional Landfill (FL panhandle)",
  "landfill_id": 409,
  "lat": 30.92104,
  "lon": -85.42854,
  "source": "hand_run",
  "measurement": {
    "hard_fail": false,
    "native_srs_label": "UTM16N NAD83(2011) EPSG:6345",
    "epoch_a_date_nominal": "2007",
    "epoch_b_date_nominal": "2020",
    "epoch_dates_independently_verified": true,
    "usable_coverage_pct": 55.8,
    "n_stable_control_cells": 55573,
    "evidence_refs": [
      "epoch_a: kind=ept label='FL_NWFWMD_5-Counties_2007' n_ground_points=496138 runtime_s=7.4",
      "epoch_b: kind=ept label='FL_HurricaneMichael_6_2020' n_ground_points=8918068 runtime_s=46.1"
    ],
    "meta": {
      "epoch_a": {
        "runtime_s": 7.384306466206908,
        "n_points": 496138,
        "text_bytes": 14884152
      },
      "epoch_b": {
        "runtime_s": 46.10752067435533,
        "n_points": 8918068,
        "text_bytes": 267542052
      },
      "grid_nx": 500,
      "grid_ny": 500
    },
    "stable_control_offset_m": 0.2009,
    "stable_control_sigma_m": 0.4602,
    "detection_threshold_m": 1.3807,
    "volume_change_m3": 627.7,
    "uncertainty_m3": 16.4,
    "uncertainty_to_change_ratio": 0.0261,
    "classification": "DECISION_USEFUL_CHANGE_DETECTED",
    "site_note": "poligono sintetico (buffer 200x200m sobre coordenada LMOP real), NO el parcel legal exacto"
  },
  "verdict": {
    "verdict": "CHANGE_CONFIRMED",
    "confidence": 0.974,
    "declared_state": "Epoch A (2007) - reference/baseline surface",
    "observed_state": "Epoch B (2020) - current surface",
    "delta": {
      "volume_change_m3": 627.7,
      "uncertainty_m3": 16.4,
      "unit": "m3"
    },
    "sensor_agreement": {
      "status": "not_applicable_single_sensor",
      "note": "physical_change compares two epochs of the same sensor modality (LiDAR vs. LiDAR) - there is no second independent sensor to cross-check against today, unlike china_industrial_reality's multi-signal (NDVI/NDBI/SAR) discipline. The stable_control_offset_m/stable_control_sigma_m fields are a real internal consistency check (calibration against known-stable ground), not a second sensor."
    },
    "evidence": [
      {
        "source": "epoch_a: kind=ept label='FL_NWFWMD_5-Counties_2007' n_ground_points=496138 runtime_s=7.4",
        "nominal_date": "2007",
        "dates_independently_verified": true,
        "n_ground_points": 496138,
        "hash": null,
        "hash_note": "No cryptographic hash of the source point cloud is computed today - real gap, not hidden.",
        "method_version": "measure_physical_change (unmodified core function across all 4 validated sites)",
        "uncertainty_m3": 16.4,
        "rights": "CC-BY 4.0"
      },
      {
        "source": "epoch_b: kind=ept label='FL_HurricaneMichael_6_2020' n_ground_points=8918068 runtime_s=46.1",
        "nominal_date": "2020",
        "dates_independently_verified": true,
        "n_ground_points": 8918068,
        "hash": null,
        "hash_note": "No cryptographic hash of the source point cloud is computed today - real gap, not hidden.",
        "method_version": "measure_physical_change (unmodified core function across all 4 validated sites)",
        "uncertainty_m3": 16.4,
        "rights": "CC-BY 4.0"
      }
    ],
    "recommended_next_action": "None - result is decisive.",
    "raw_measurement": {
      "hard_fail": false,
      "native_srs_label": "UTM16N NAD83(2011) EPSG:6345",
      "epoch_a_date_nominal": "2007",
      "epoch_b_date_nominal": "2020",
      "epoch_dates_independently_verified": true,
      "usable_coverage_pct": 55.8,
      "n_stable_control_cells": 55573,
      "evidence_refs": [
        "epoch_a: kind=ept label='FL_NWFWMD_5-Counties_2007' n_ground_points=496138 runtime_s=7.4",
        "epoch_b: kind=ept label='FL_HurricaneMichael_6_2020' n_ground_points=8918068 runtime_s=46.1"
      ],
      "meta": {
        "epoch_a": {
          "runtime_s": 7.384306466206908,
          "n_points": 496138,
          "text_bytes": 14884152
        },
        "epoch_b": {
          "runtime_s": 46.10752067435533,
          "n_points": 8918068,
          "text_bytes": 267542052
        },
        "grid_nx": 500,
        "grid_ny": 500
      },
      "stable_control_offset_m": 0.2009,
      "stable_control_sigma_m": 0.4602,
      "detection_threshold_m": 1.3807,
      "volume_change_m3": 627.7,
      "uncertainty_m3": 16.4,
      "uncertainty_to_change_ratio": 0.0261,
      "classification": "DECISION_USEFUL_CHANGE_DETECTED",
      "site_note": "poligono sintetico (buffer 200x200m sobre coordenada LMOP real), NO el parcel legal exacto"
    }
  },
  "independent_cross_check": {
    "mass_run_hard_fail": false,
    "mass_run_volume_change_m3": 627.7,
    "mass_run_offset_m": 0.2009,
    "mass_run_sigma_m": 0.4602
  }
}