ZIP 19344: your water comes from Aqua PA Uwchlan
Aqua PA Uwchlan is the only community water system that reports serving ZIP 19344 (Chester County and Lancaster County, Pennsylvania) under EPA's UCMR 5 (reported by the system to EPA). PFAS-4 at the latest sample (2024): 13 ng/L. Systems report their own ZIP lists to EPA; if your water bill names another utility, that utility's page carries its own results.
Where this ZIP is
This site is a data project, not an official source. If in doubt, check with your water supplier or local authority.