The department is authorized to fix a maximum speed limit at which trains may be run over any grade crossing of a highway or other way and, when the limit has been fixed by the department, no engine or train may be run over the crossings at a greater speed than that fixed by the department and no way may be unreasonably and negligently obstructed by engines, tenders or cars. Any railroad corporation forfeits not more than $100 for every violation of this section.   [PL 1989, c. 398, §8 (NEW).]