Schools matter most here: they concentrate the sensitive receptor (children), they sit on the same former ranch land, and, under California's 2000 school-siting law, they are the one land use that triggers a mandatory environmental look. So what that look tested for is the whole question. The headline: where school soil was sampled at all, the analytes were chosen for orchards and landfills, never for the cattle-dip signature. Arsenic trioxide, the poison used in dipping, has never been an analytical target at any school in these communities.
| Site (area) | Review / borings | Analytes actually tested | Arsenic tested? | Which signature |
|---|---|---|---|---|
| Oso Grande ES, Ladera Ranch | Phase 1 + Phase 1 Addendum (2003), records + walk, no soil borings [A2] | None, no soil sampled | No | - |
| Ladera Ranch ES / MS, Chaparral ES, Ladera | No DTSC school-investigation soil study located [A2] | None located | No | - |
| Carl Hankey ES, Mission Viejo / Ladera edge (former orchard + row crops) | EnviroStor school investigation, soil sampled, No Further Action [A1] | Arsenic · Lead · Methane | Yes | Lead-arsenate (orchard), arsenic read with lead, as crop-pesticide residue. NOT the low-lead dip signature |
| TTM 17325, Coto de Caza (adjacent tract, former shooting range) | Phase II + Remedial Action Plan (2011) [A2] | Lead · PAH (clay-target debris) | No | (metals suite did not target arsenic) |
Read this table carefully. Only one nearby school (Carl Hankey) ever had soil tested for arsenic and that was because it sat on a former orchard, so the investigation looked for lead-arsenate (arsenic bound with lead, the orchard pesticide). A cattle dip leaves the opposite chemical fingerprint: arsenic trioxide, arsenic with little or no lead. No school study has ever tested for that. The dip signature has never been ruled in or out anywhere in these communities. That is the single most important, and most fixable, gap in the record.
| School | Operator | Grades | Opened | EnviroStor |
|---|---|---|---|---|
| Chaparral Elementary | Capistrano USD | TK-5 | 2001 (first Ladera school) | none located |
| Ladera Ranch Elementary | Capistrano USD | TK-5 | 2003 | none located |
| Ladera Ranch Middle | Capistrano USD | 6-8 | 2003 | none located |
| Oso Grande Elementary | Capistrano USD | PK-5 | 2005 | ID 30020004, Phase 1, paper-only |
| Montessori of Ladera Ranch | Private | PK-2 | - | none located |
| The Goddard School | Private | Infant-PK | - | none located |
| Ladera Ranch KinderCare | Private | Infant-PK | - | none located |
| Pacific Preschool | Private | PS-K | - | none located |
| Discovery Montessori | Private | Preschool | - | none located |
| Stoneybrooke Christian (Ladera campus, closed 2015) | Private | Elem+JH | 2003 | none located |
| School | Operator | Grades | Opened | EnviroStor |
|---|---|---|---|---|
| Wagon Wheel Elementary (Wagon Wheel village, west of the Joplin patent ground) | Capistrano USD | K-5 | 1997 | none located |
| Trabuco Elementary (Trabuco Canyon) | Saddleback Valley USD | TK-6 | 1980 site | none located |
| Robinson Elementary (Robinson Ranch) | Saddleback Valley USD | TK-6 | 1994 | none located |
| Portola Hills Elementary | Saddleback Valley USD | K-6 | 1992 | none located |
| Dove Canyon Montessori | Private | Infant-3 | - | none located |
No school exists inside the Coto de Caza gates; Coto children attend the schools above plus Tijeras
Creek ES / Arroyo Vista TK-8 / Tesoro HS in neighboring Rancho Santa Margarita. Full rosters for
Rancho Santa Margarita (15), Las Flores (2), Newport Coast (2), and Eastbluff/Santa Ana Heights (6)
are in research/schools/AREA_SCHOOL_ROSTERS.md.
"None located" is not a clean bill of health, it means no DTSC school-investigation soil study was found in the public record, and EnviroStor's per-school pages were bot-gated to automated search on the compile date (a data gap flagged for interactive verification). For most of these schools, no mandatory soil look was ever triggered at all. Absence of an entry means the question was never opened, not that it was answered.