Farm Environmental Passport: a status-and-gap method for screening the environmental pathways of a single farm, with PFAS as the first module

Methods note (preprint, version 1). The Farm Environmental Passport is a repeatable screening procedure for one specific farm. It reconciles open data and existing analyses against thresholds stored with their legal status and date; only measured objects receive a colour status, everything else stays grey and enters a gap registry with the sample that would close it. Doses are computed for four mandatory scenarios, including an infant fed formula prepared with well water and a resident young child, with Monte Carlo uncertainty and sensitivity indices that rank the next samples by the value of the information they add. The method is demonstrated on a synthetic dairy farm in Delaware County, New York; all laboratory values are synthetic. It has not yet been validated on a real farm; version 2 will report a field pilot. The passport is screening and expert opinion, not a compliance determination or medical advice.