The Acid Deposition System (ADS) data base for North American wet deposition data is used to provide an overview of the major North American monitoring networks: NADP, CANSAP, APN, MAP3S/PCN, EPRI/SURE, UAPSP and APIOS daily and cumulative. Individual site annual statistical summaries for calendar years 1980, 1981, and 1982 are given for pH, specific conductance, hydrogen ion (derived from pH) and ion species sulfate, nitrate, ammonium, calcium, chloride, sodium, magnesium and potassium. The summaries are prepared under common valid sample screening criteria and four criteria used to determine the reporting of individual sites. Based on the annual summaries, 1980, 1981, and 1982, North American spatial isopleth maps are constructed for precipitation weighted mean pH, sulfate ion and nitrate ion concentrations and annual deposition of hydrogen, sulfate and nitrage ion species. The Acid Deposition System (ADS) for data storage and statistical reporting of atmospheric deposition data has been established by the EPA at the Pacific Northwest Laboratory (PNL). ADS provides an integrated centralized data bank for data collected by all atmospheric deposition monitoring networks in North America. The centralized data base facilitates access to deposition data collected by different organizations; provides annual inventories of available data; and maintains the data for the assessment of long-term national trends.