TheOceanoDunesStateVehicleRecreationArea(SVRA)emitssignificantlymoreparticulatematter(PM)dust thanthenaturalbackgroundemissionlevelsmeasuredinnon-ridingduneareas.Thisfactisapparentinthe aerialphotograph(left)oftheNipomoMesa.Thevisible,concentrateddustplumeoriginatesfromtheSVRA riding area and extends over the southwest part of the mesa. No plume is visible north or south of this.UnnaturalPMconcentrationsareemittedfromtheOceanoDunesSVRAanytimethereison-shorewind.However,duringperiodsofhighwindtheconcentrationsfrequentlyexceedthePM10andPM2.5health standardsestablishedbytheCaliforniaAirResourcesBoard,andviolatetheSanLuisObispoCountyAir PollutionControlDistrict(APCD)Rule1001.OnJune12,2017theAPCDAirPollutionControlOfficerissueda Notice of Violation to the State Parks OHMVR Division Acting Deputy Director.PMdustpollutionlevelsaremeasuredbytheAPCDatseveralmonitoringsitesintheSouthCountyarea.ThedatafromthesesitesisusedtoissueforecastPM pollution alerts, and to document violation of air quality standards.
Report summarizing Phase 1 and Phase 2 South County PM Studies. Conclusion: Off-Highway vehicle activity in the SVRA is a major contributing factor to the high PM concentrations observed on the Nipomo Mesa.