{"schemaVersion":2,"id":"us-MA4221000","communeId":"MA4221000","name":"Oak Bluffs Water District","slug":"oak-bluffs-water-district-ma4221000","country":"us","region":"Massachusetts","supplier":"OAK BLUFFS WATER DISTRICT","networks":[{"code":"00012/EP001","name":"Entry Point to Dist. System (Well 1 Lagoon Pond TP)"},{"code":"00013/EP002","name":"Entry Point to Dist. System (Well 2 Farm Neck Road TP)"},{"code":"00014/EP003","name":"Entry Point to Dist. System (Well 3 State Forest TP)"},{"code":"00015/EP004","name":"Entry Point to Dist. System (Well 4 Alwardt)"},{"code":"00016/EP005","name":"Entry Point to Dist. System (Well 5 Randolph)"}],"latestSampleDate":"2023-12-13T00:00:00Z","conformity":{"conclusion":null,"bacteriological":"unknown","chemical":"unknown"},"source":{"name":"U.S. Environmental Protection Agency, Fifth Unregulated Contaminant Monitoring Rule (UCMR 5) occurrence data, final dataset (August 2026)","url":"https://www.epa.gov/dwucmr/occurrence-data-unregulated-contaminant-monitoring-rule","license":"Public domain (U.S. federal government work, 17 U.S.C. § 105)","kind":"open_data_file","verified":true,"retrievedAt":"2026-09-19T19:22:35.464Z","note":"UCMR 5 results do not indicate compliance or noncompliance with the PFAS drinking water standards. Samples are taken at the entry point to the distribution system, not at the tap; the system may have changed sources or installed treatment since. Treatment reported to EPA for PFAS: no PFAS treatment (NMT). 5 entry points sampled, 10 sampling events between 2023-06-21 and 2023-12-13. The page's PFAS values come from the newest sample at Entry Point to Dist. System (Well 1 Lagoon Pond TP) (00012/EP001), the entry point with the highest PFOA + PFOS + PFNA + PFHxS sum; the other entry points' maxima are listed as separate rows. Non-detects are shown as \"<\" followed by EPA's minimum reporting level (3 to 20 ng/L); PFAS-4 sums quantified compounds only, so it is a lower bound when a compound was not detected. Registry (name, population, counties, ZIPs) from EPA SDWIS/ECHO; service-area centroid from EPA ORD."},"pfas":{"status":"measured","sum20":null,"pfas4":{"value":null,"valueText":"<0.015","unit":"µg/L","limit":0.004,"limitUnit":"µg/L","status":"ok","sampleDate":"2023-12-13T00:00:00Z","sampleId":"L2374216-01","nonDetect":true,"upperBound":0.015},"pfas4DetectedCount":0,"lowerBound":true,"sampledAt":{"commune":"MA4221000","name":"Entry Point to Dist. 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