Know your data sources.

Illinois EPA site remediation, leaking USTs, landfills, brownfields, and federal-facility cleanup via geoservices.epa.illinois.gov. - searchSiteRemediation ⭐ ~6.6K SRP cleanup sites with County + SiteType (64 distinct) - searchLeakingUST ⭐ ~31.3K LUST sites — NO county column upstream - searchLandfills ⭐ ~1041 landfills across 6 status-typed layers - searchBrownfields, searchFederalFacilities, getServiceInfo §0: Environmental/LeakingUST and Environmental/IEPA_BOL_SiteRemediationProgram are DEAD (layers=[], 500s). Live equivalents: Land/LeakingUST, Land/SrpSites. FederalFacilities canonical is layer 1 (parent 0 is group). Active 0/1 ↔ SiteActive Yes/No same partition. All four services in EPSG:4326.

Indiana IDEM Superfund, cleanup, voluntary remediation, hazardous waste, LUST, brownfields, solid-waste via gisdata.in.gov state Hub. - searchSuperfundSites ⭐ ~85 federal NPL & SF list (program=SF) - searchCleanupSites ⭐ ~1.5K State Cleanup Sites (program=SC) - searchVoluntaryRemediation ⭐ ~653 VRP sites (program=VR) - searchBrownfields (~2.3K w/ county), searchHazardousWasteSites, searchLustSites, searchSolidWasteFacilities §0: maps.indiana.edu (build-plan brief) is unreachable (TCP timeout). Canonical data on gisdata.in.gov Hosted/IDEM_Land_Sites — IDEM/ folder requires auth. Layers 1500/1600/1800/1900/2300 share schema and have NO county column (municipality only); 1100 + 1000 have county. agency_interest_id is Double.

NM Environment Department permits + remediation. Native ArcGIS REST FeatureServers, no auth. - searchGroundwaterDischargePermits ⭐ — Permian produced-water + UIC permits (~1.1K) - searchAirQualityPermits ⭐ — 7-class layer: major (default, ~37K) / minor / synthetic-minor / ... - searchHazardousWasteFacilities (21 RCRA-permitted sites, no county) - searchVoluntaryRemediation — VRP brownfield-style cleanups (~163) - getServiceInfo quirks: GWDP STATUS has 13 distinct values (Active / Pending / Ceased / Terminated / Withdrawn / Denied / ...). VRP STATUS dirty (Termin / ActIve / Closed / closed / Condit / Applic / CCOC) — case-insensitive. Air Facilities split across 7 FACILITY_CLASS layers; non-major returns millions of emission units, always pass county/bbox.

Oklahoma DEQ wellhead protection + remediation + monitoring. Native ArcGIS REST MapServers, no auth. - searchWellheadProtectionAreas ⭐ — drilling-restriction polygons (~5.9K) around PWS - searchRemediationSites ⭐ — Institutional Controls (~890) under formal cleanup programs - searchVoluntaryCleanupSites, searchAccreditedLabs (~151), searchAirQualitySites (28) - getServiceInfo quirks: WHPA has NO name / county / facility id — only ZONE (A/B/C) + SOURCE_IND. Filter zone or bbox. Remediation County values dirty (Garfeld vs Garfield, "Tulsa" vs "Tulsa County") — handler LIKE-matches + Title-Case strips trailing " County". LabAccred Lab_Type has typos. Base_Certification_Status always 'Accredited'. Air POLLUTANTS comma-joined; LIKE-matched.

WVDEP consolidated. Marcellus heart — EQT, Antero, Range, Southwestern. 11 services in one enterprise folder, 9 layers via 8 methods. - searchWells (~153K) ⭐ county (→FIPS), operator, status, wellType, formation, marcellus/horizontal flags - searchPermits ⭐ orderBy issuedate desc; permitType, yearFrom/To - searchAirEmissionSources (~2.6K), searchAbandonedMineLands (~10K), searchRemediationSites (VRP+SEMS), searchMiningReclamation (~11K), searchDamSafety (~395), searchWatershedAssessment (~34K 303d), getServiceInfo upstream quirks: county on wells = FIPS suffix (Wetzel='103'). marcellus 'y'/'n'/'u' string. Mining columns are type/per_status. SEMS columns 10-char truncated. AML status bracketed variants. Air/AML/VRP/Mining/Dam/Watershed have NO county column — bbox/near only.