All unused and abandoned surface openings shall be effectively closed or fenced against unauthorized entrance.
Code 1950, § 45-71.1; 1954, c. 191; 1966, c. 594, § 45.1-95; 1984, c. 228; 1985, c. 395; 1990, c. 372; 1992, c. 360; 1994, c. 28; 1999, c. 256.