Rockland County legislators voted unanimously last night to appoint Moshe Hopstein to fill the District 13 seat left vacant by former legislator Aron Wieder, who was elected in November to the state Assembly. Hopstein currently serves as Chairman of the Village of Spring Valley Zoning Board of Appeals, and has served on the East Ramapo Central School District Board of Education. District 13 includes a large part of Spring Valley and portions of unincorporated Ramapo.