If in the case of any crossing it appears that the placing of such signs is impracticable or unnecessary, the department of transportation, on petition of the governmental authority responsible for maintaining the highway on which such crossing is situated, may release such governmental authority from the obligation of placing and maintaining the same.
RSA 246:13
1915, 4:3. PL 249 :17. RL 299:20. 1951, 203:58 par. 13. RSA 373:13. 1977, 41:2. 1985, 402:6, I(e)(5).