Hearth & Horizon has a new science fiction story, The Eighteenth Place, set in an invented Pennsylvania mill town in March 2048.
In the US, the lead rule compares the 90th percentile of first-draw samples to an action level (10 µg/L under the 2024 revisions). With 20 samples that is the 18th value from the lowest. In the story it is 8.6, so the town passes, and the two samples above it are 31 and 44. The town's water assistant reads all twenty numbers, will not call the town safe or unsafe, and gives the range the sample supports: 2 in 20 is consistent with 1.2 to 32 percent of lead-line homes above ten, which is 23 to 600 of 1,900. (An exact binomial interval; anyone can reproduce it.)
Then it asks for two more bottles at the house with the 44: one after two minutes of running, one from the service line in the cellar. The answer, 39, 3.1 and 6.4, points at a 1991 brass faucet, not the street. The council adopts a three-highest reporting rule, a 60-home retest, and a pipe-replacement order that puts children and pregnant women first. It also hears why replacing only the town's half of a lead line can make things worse for a while.
The town, people and numbers are invented; the rules and methods are real, and the story's notes say which is which. It is fiction written by an AI, CC BY-SA 4.0, and text only for now because the audio folders are past the 400 MB budget.