By Pamela Wofford, Environmental Monitoring Branch

Lompoc is a small city located in a coastal valley of Santa Barbara County, California, with agricultural fields located in the area between Lompoc and the coast. As with most California coastal valleys, the area is cool with frequent fog or low cloudiness, and winds are predominantly from the west or northwest; Lompoc is downwind from the agricultural area. The Department of Pesticide Regulation (DPR) conducted air monitoring in Lompoc to determine whether, and in what amounts, fumigant pesticides occur in air in residential areas of the city. Three fumigant pesticides are used in the Lompoc area: chloropicrin, methyl bromide, and methyl isothiocyanate (MITC, breakdown product of metam-sodium and metam-potassium). DPR monitored five locations, including two schools in Lompoc, primarily choosing higherrisk sites based on their proximity to agricultural areas. The monitoring plan targeted selected applications, specifically large fumigations in close proximity to Lompoc. DPR monitored six MITC fumigations, and two methyl bromide/chloropicrin fumigations during 2000. For each of the fumigations, DPR monitored for a 72-hour period beginning with the start of fumigation. The 72-hour monitoring period consisted of six alternating 8-hour (day) and 16hou

Inventory of research and development projects.

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Thermocouple readout instrument /

Includes bibliographical references (page 14).Mode of access: Internet