MONTICELLO — Local government and economic development leaders said on Friday that Sullivan County is steadily progressing in planning for and luring developers to build two light industrial parks.Of the two sites, a 78-acre, county-owned parcel located in the Town of Thompson and the Village of Monticello, could be developed faster, they said.That land has been vacant since a plan was scrapped a decade ago to expand the nearby Sullivan County Landfill.