Utility companies in New Jersey have the legal authority to levy fines???!
No, it is a civil fine but the utility could be the one that reports you.
The Act subjects violators of its provisions to civil penalties of not less than $1,000 and not more than $2,500 per violation per day. N.J.S.A. 48:2-88. In addition, the violator may be assessed the cost of any Board investigation, inspection or monitoring survey which leads to the establishment of a violation and for the reasonable costs of preparing and litigating the matter. N.J.S.A. 48:2-86(b)(2)
It's pretty much the same all over, if you don't simply call the free utility marking number and go ahead and dig up a utility you will be liable for all damages and the fines.