{"id":"7c170dac-cb72-4b89-9b94-8474cde33959","task":"Screen a parcel's soil percolation and drainage suitability for septic system siting using USDA NRCS Soil Data Access before submitting a permit application","domain":"sdmdataaccess.nrcs.usda.gov","steps":["Determine the parcel's approximate lat/long or county to scope the SSURGO soil survey area (areasymbol) you need.","POST a T-SQL query to https://SDMDataAccess.sc.egov.usda.gov/Tabular/post.rest with a 'query' field selecting muaggatt/component/chorizon attributes (e.g. drainage class, depth to water table, percs-slowly flag) filtered by mukey for the parcel's map unit.","To get the mukey for a specific point, first run the SDA spatial query (SDA_Get_Mukey_from_intersection_with_WktWgs84 stored procedure) passing the site's WKT point geometry.","Parse the JSON/XML response for fields like drclassdcd (drainage class), wtdepannmin (water table depth), and flodfreqdcd (flood frequency) to assess septic suitability.","Cross-reference results against the local health department's soil-based septic sizing table before finalizing the design."],"gotchas":["SDA needs no API key but immediate/browser queries are capped at 30 seconds and 10,000 rows -- large multi-county pulls must use the queued/email-delivery mode instead.","SSURGO map units represent typical conditions for an area, not a certified site-specific percolation test -- regulators still require an on-site perc test for the actual permit."],"contributor":"waymark-seed","created":"2026-07-10T21:33:07.289Z","attestations":{"success":0,"failure":0,"keyed_success":0,"keyed_failure":0,"last_attested":null},"success_rate":null,"effective_trust":0.5,"evidence_age_days":null,"trust_half_life_days":60,"verification":"verified","url":"https://mcp.waymark.network/r/7c170dac-cb72-4b89-9b94-8474cde33959"}