{
  "answerability": "evidence_backed_claims_available",
  "claims": [
    {
      "claim": {
        "claim_id": "claim-park-thurgood-marshall-regional-park-home-port-chicago-50-boundary-geometry-20260924",
        "evidence_ids": [
          "evidence-park-thurgood-marshall-regional-park-home-port-chicago-50-boundary-geometry-20260924"
        ],
        "predicate": "managed_land_boundary_geometry",
        "spatial_scope_ids": [],
        "subject_id": "park-thurgood-marshall-regional-park-home-port-chicago-50",
        "temporal_scope": null,
        "value": {
          "boundary_geometry_snapshot": {
            "feature_ids": [
              "ebrpd:123"
            ],
            "path": "geometry/v0/snapshots/ebrpd-managed-land-boundaries-20260924.geojson",
            "sha256": "4e6558956f4f397816d719ff87554289e08dd495314b2d57c83d1634f083e3e5"
          },
          "boundary_type": "managed_land_status_polygons",
          "coordinate_precision_decimal_degrees": 5,
          "coordinate_reference_system": "EPSG:4326",
          "navigation_grade": false
        }
      },
      "evidence": [
        {
          "claim_id": "claim-park-thurgood-marshall-regional-park-home-port-chicago-50-boundary-geometry-20260924",
          "evidence_id": "evidence-park-thurgood-marshall-regional-park-home-port-chicago-50-boundary-geometry-20260924",
          "notes": "Supports the selected source polygons and their retained boundary semantics.",
          "observation_id": "observation-managed-land-boundaries-ebrpd-20260924",
          "stance": "supports"
        }
      ],
      "observations": [
        {
          "artifact_refs": [
            "geometry/v0/snapshots/ebrpd-managed-land-boundaries-20260924.geojson"
          ],
          "content": "EBRPD's open-data layer reports the selected current managed-land polygons; parkland and landbank status remain separate.",
          "observation_id": "observation-managed-land-boundaries-ebrpd-20260924",
          "observed_at": null,
          "observer": "",
          "retrieved_at": "2026-09-24T22:00:00+00:00",
          "source_id": "source-ebrpd-managed-land-boundaries-20260924"
        }
      ],
      "sources": [
        {
          "locator": "https://services2.arcgis.com/jeEP9c9zZoQQwtck/arcgis/rest/services/EBRPD_Parks/FeatureServer/0",
          "publisher": "East Bay Regional Park District",
          "source_id": "source-ebrpd-managed-land-boundaries-20260924"
        }
      ],
      "subject": {
        "entity_id": "park-thurgood-marshall-regional-park-home-port-chicago-50",
        "kind": "park",
        "name": "Thurgood Marshall Regional Park - Home of the Port Chicago 50"
      }
    },
    {
      "claim": {
        "claim_id": "claim-thurgood-marshall-no-public-access",
        "evidence_ids": [
          "evidence-thurgood-marshall-no-public-access"
        ],
        "predicate": "operating_status",
        "spatial_scope_ids": [],
        "subject_id": "park-thurgood-marshall-regional-park-home-port-chicago-50",
        "temporal_scope": {
          "ends_on": null,
          "starts_on": null
        },
        "value": {
          "exception": "occasional public tour events",
          "status": "closed_no_public_access"
        }
      },
      "evidence": [
        {
          "claim_id": "claim-thurgood-marshall-no-public-access",
          "evidence_id": "evidence-thurgood-marshall-no-public-access",
          "notes": "Live EBRPD alert; recheck the official alerts page before travel.",
          "observation_id": "observation-ebrpd-alerts-closures-20260922",
          "stance": "supports"
        }
      ],
      "observations": [
        {
          "artifact_refs": [
            "Alerts and Closures table"
          ],
          "content": "The district alerts page published the park, trail, facility, and water conditions represented by the associated claims. Entries with insufficient page context were not promoted.",
          "observation_id": "observation-ebrpd-alerts-closures-20260922",
          "observed_at": null,
          "observer": "Wayproof live source review",
          "retrieved_at": "2026-09-22T18:30:00+00:00",
          "source_id": "source-ebrpd-alerts-closures"
        }
      ],
      "sources": [
        {
          "locator": "https://www.ebparks.org/alerts-closures",
          "publisher": "East Bay Regional Park District",
          "source_id": "source-ebrpd-alerts-closures"
        }
      ],
      "subject": {
        "entity_id": "park-thurgood-marshall-regional-park-home-port-chicago-50",
        "kind": "park",
        "name": "Thurgood Marshall Regional Park - Home of the Port Chicago 50"
      }
    },
    {
      "claim": {
        "claim_id": "claim-thurgood-marshall-regional-park-home-port-chicago-50-visitor-profile",
        "evidence_ids": [
          "evidence-ebrpd-thurgood-marshall-regional-park-home-port-chicago-50-visitor-profile"
        ],
        "predicate": "visitor_profile",
        "spatial_scope_ids": [
          "scope-thurgood-marshall-regional-park-home-port-chicago-50"
        ],
        "subject_id": "park-thurgood-marshall-regional-park-home-port-chicago-50",
        "temporal_scope": null,
        "value": {
          "future_acreage": 3000,
          "future_facilities": [
            "visitor center",
            "public transit routes",
            "public access points",
            "staging areas",
            "camping",
            "hiking",
            "biking",
            "picnic areas"
          ],
          "location": "Concord Hills",
          "planning_note": "future facilities are planned rather than currently available",
          "public_access": "occasional naturalist-led tours and public events only",
          "purpose": [
            "interpret the Port Chicago disaster and the Port Chicago 50",
            "connect communities",
            "protect habitat and wildlife corridors"
          ],
          "status": "land bank; closed with no general public access"
        }
      },
      "evidence": [
        {
          "claim_id": "claim-thurgood-marshall-regional-park-home-port-chicago-50-visitor-profile",
          "evidence_id": "evidence-ebrpd-thurgood-marshall-regional-park-home-port-chicago-50-visitor-profile",
          "notes": "Direct transcription and conservative structuring of planning-relevant fields from the official park page.",
          "observation_id": "observation-ebrpd-thurgood-marshall-regional-park-home-port-chicago-50-visitor-profile",
          "stance": "supports"
        }
      ],
      "observations": [
        {
          "artifact_refs": [
            "Overview",
            "To Reach The Park",
            "Attractions"
          ],
          "content": "The live park page publishes the visitor profile represented by the associated claim, including access, operating information, facilities, and material restrictions.",
          "observation_id": "observation-ebrpd-thurgood-marshall-regional-park-home-port-chicago-50-visitor-profile",
          "observed_at": null,
          "observer": "Wayproof live source review",
          "retrieved_at": "2026-09-20T07:00:00+00:00",
          "source_id": "source-ebrpd-thurgood-marshall-regional-park-home-port-chicago-50-park-page"
        }
      ],
      "sources": [
        {
          "locator": "https://www.ebparks.org/parks/thurgood-marshall-regional-park-home-port-chicago-50",
          "publisher": "East Bay Regional Park District",
          "source_id": "source-ebrpd-thurgood-marshall-regional-park-home-port-chicago-50-park-page"
        }
      ],
      "subject": {
        "entity_id": "park-thurgood-marshall-regional-park-home-port-chicago-50",
        "kind": "park",
        "name": "Thurgood Marshall Regional Park - Home of the Port Chicago 50"
      }
    }
  ],
  "entity": {
    "entity_id": "park-thurgood-marshall-regional-park-home-port-chicago-50",
    "kind": "park",
    "name": "Thurgood Marshall Regional Park - Home of the Port Chicago 50"
  },
  "gap_details": [],
  "history": [
    {
      "action": "ADD",
      "change_set_id": "wp-20260921-ebrpd-parks-batch-13",
      "evidence_refs": [],
      "knowledge_gap_refs": [],
      "path": "canonical/v0/entities/park-thurgood-marshall-regional-park-home-port-chicago-50.json",
      "reason": "Add a deduplicated planning profile from the live EBRPD preserve page reviewed on 2026-09-20.",
      "record_id": "park-thurgood-marshall-regional-park-home-port-chicago-50",
      "record_type": "entity",
      "summary": "Add four additional previously uncaptured EBRPD park visitor profiles."
    },
    {
      "action": "ADD",
      "change_set_id": "change-managed-land-boundary-backfill-20260924",
      "evidence_refs": [
        "evidence-park-thurgood-marshall-regional-park-home-port-chicago-50-boundary-geometry-20260924"
      ],
      "knowledge_gap_refs": [],
      "path": "canonical/v0/claims/claim-park-thurgood-marshall-regional-park-home-port-chicago-50-boundary-geometry-20260924.json",
      "reason": "Backfill reviewed managed-land boundary geometry",
      "record_id": "claim-park-thurgood-marshall-regional-park-home-port-chicago-50-boundary-geometry-20260924",
      "record_type": "claim",
      "summary": "Backfill reviewed boundary geometry for every published park, national park, and wilderness entity"
    },
    {
      "action": "ADD",
      "change_set_id": "wp-20260922-ebrpd-current-conditions",
      "evidence_refs": [],
      "knowledge_gap_refs": [],
      "path": "canonical/v0/claims/claim-thurgood-marshall-no-public-access.json",
      "reason": "Materialize an unambiguous actionable condition from the district alerts page.",
      "record_id": "claim-thurgood-marshall-no-public-access",
      "record_type": "claim",
      "summary": "Materialize current EBRPD closures and water disruptions for pre-trip rechecks."
    },
    {
      "action": "ADD",
      "change_set_id": "wp-20260921-ebrpd-parks-batch-13",
      "evidence_refs": [
        "evidence-ebrpd-thurgood-marshall-regional-park-home-port-chicago-50-visitor-profile"
      ],
      "knowledge_gap_refs": [],
      "path": "canonical/v0/claims/claim-thurgood-marshall-regional-park-home-port-chicago-50-visitor-profile.json",
      "reason": "Add a deduplicated planning profile from the live EBRPD preserve page reviewed on 2026-09-20.",
      "record_id": "claim-thurgood-marshall-regional-park-home-port-chicago-50-visitor-profile",
      "record_type": "claim",
      "summary": "Add four additional previously uncaptured EBRPD park visitor profiles."
    }
  ],
  "journey": [],
  "knowledge_gaps": [],
  "reference_evidence": [],
  "relationships": [],
  "route_geometry": null,
  "route_geometry_url": null,
  "type": "canonical_entity"
}