Aerial pesticide spraying in Uintah Basin, UT continued to be an issue of public concern in the summer of 1980. A number of developments occurred in the Vernal-Maeser area, and Utah in general, regarding aerial spraying near residential communities: (i) the extension pesticide coordinator for the state issued a memorandum recommending the use of less toxic pesticides than the parathions, (2) a community meeting, organized by the Federal Aviation Agency, was conducted in the Uintah Basin, (3) this laboratory agreed to share the results of a spray monitoring study under way with the public, and (4) one aerial applicator in the Uintah Basin closed his operation. The present report describes a spray drift study conducted in Maeser, UT on 5 and 6 June 1980. This study employed highvolume air sampling equipment and meteorological instruments not available in an earlier study of parathion spraying (DRAPER & STREET 1981); only foliar residues were measured in the previous investigation. The pesticide applied in 1980 was carbofuran, possibly as a result of the University's recommendation. The objective, as with the previous year's study, was to obtain an estimate of the extraneous exposure that a bystander might be subjected to. Specifically, inhalation and dermal exposure during and immediately subsequent to aerial spraying were to be estimated. The experimental format and assumptions made in the data treatment were oriented toward obtaining a "worst-case" estimate. EXPERIMENTAL