The rating on Rhode Island Health and Educational Facilities Building Corp.'s bonds, issued for South County Hospital (SCH), reflects: A dominant market and competitive position due to low costs, Solid outpatient care business, and A strong balance sheet backed by the guarantee of the hospital's foundation. These strengths are offset by the hospital's small size of only 100 beds and an increasingly restrictive payor mix. The bonds are secured by a gross revenue pledge of the hospital and a guarantee from the hospital's foundation. SCH is a 100-bed acute-care facility located in the Wakefield area of South Kingstown, 30 miles south of Providence and 20 miles away from the nearest hospitals. The hospital's market share in its primary market remains