This database ranks Arkansas' 643 conventional water utilities based on the lead level in tap water testings — measured in parts per billion — for the last available testing period of each utility. The database shows the date of the last sampling, how many samples were taken, and of those how many tested above the action level.
The federal "action level" is considered any score over 15 parts-per-billion.
The second column of the database shows a utility's "90th percentile score," which means that at least 90 percent of the samples tested at or below that value. This is how the scoring is kept by the Arkansas Department of Health.