Every home in Los Angeles County, drawn by how far it sits from the nearest plant that files a federal Risk Management Plan for the chemicals it holds. One dot is one residential parcel, 2,076,970 of them, and 222,827 are inside a mile of one of the county's 109 active sites. Isolate the cold chain from the water utilities and two different Los Angeleses separate out. Zoom to your block.
Every dot is a home, colored by how far it sits from the nearest facility that files a federal Risk Management Plan. That program covers accidental releases, not routine pollution. A plant can hold ammonia for forty years and release none of it. Nothing here measures the air you breathe, and 85 of the 109 active sites have never filed an accident at all.
The one mile ring is our choice. EPA withholds every facility's own modeled harm distance under federal rule, so nobody outside the agency knows how far a given release would carry. A mile is legible. It is not a blast radius.
The record we do have: 84 accidents at these facilities from 1994 to 2023, no deaths in the record, and 17 people treated offsite in thirty years. Almost all of the sheltering in that history came from one refinery in Torrance.
The register also starts at a threshold, 10,000 pounds for anhydrous ammonia. California's own list reaches down to 500 pounds, though whether a facility at that level has to file at all is a case-by-case call by the local agency, and no statewide list of them is published. Absence from this map is not evidence of safety.
If your home sits inside a ring, what you have learned is who your neighbor is. That is worth knowing. It is not a warning.
Nothing you type leaves your browser. There is no geocoder here: the street index is inside this page.
Scroll to zoom, drag to pan. Street names appear as you zoom in. Hover a facility for what it holds and what it has reported. Choosing a sector or a chemical draws a one-mile ring around each site in it; the homes keep their color, which is always the distance to the nearest active site of any kind.