Robert F.Matthews;62;of 221 Dull St.;Fairhope;Belle Vernon;died Friday;Aug.24;1990;at 8:30 p.m.;in Shadyside Hospital;Pittsburgh.  Born May 18;1928;in Monessen; he was the son of the late Fred Matthews and Eva Ruby Matthews of Fairhope;Belle Vernon;who survives.  A law enforcement officer for approximately 18 years;Mr.Matthews had been chief of the Washington Township Police Department for the past seven years.  He retired from that post June 1;1990.  He was also a retiree of Wheeling-Pittsburgh Steel Corp.;with a total of nearly 40 years at both the Allenport and Monessen plants.  A graduate of Monessen High School;Mr.Matthews had spent much of his adult life in the Fairhope area.  He was a member of St.Sebastian Roman Catholic Church;Belle Vernon.  A U.S.Army veteran of the Korean Conflict;he was a life member of Uniontown Veterans of Foreign Wars Post 4.  He was also a member of the Fraternal Order of Police and the Western Pennsylvania Chiefs of Police Association.  He was president of the Mon Valley Chiefs Association.  In addition to his mother;he is survived by his wife;Barbara Kudlac Matthews;one son and daughter-in-law;Capt.Robert M.and Karen Matthews of Ellsworth Air Force Base;Rapid City;S.D.;one daughter;Mrs.Robert (Robyn) Roche of West Mifflin;one grandson;Robbie Roche;two brothers;Fred Matthews of Martinsburg;W.Va.;and Bernard Matthews of Monroeville;and two sisters;Claudia Rossi of Long Branch and Donna Jodon of Monongahela.  Friends will be received Sunday and Monday from 2 to 4 and 7 to 9 p.m.in the Ferguson Funeral Home Inc.;700 Broad Ave.;Belle Vernon;where a Blessing service will be held Tuesday at 9:30 a.m.;followed by Mass of Christian Burial at 10 a.m.in St.Sebastian Roman Catholic Church;Belle Vernon.  Interment will follow in Belle Vernon Cemetery.  Arrangements are being handled by the Ferguson Funeral Home Inc.