It's true that this is a civil matter, and the police were right to refuse to get involved. As far as liability is concerned, in North Carolina “Generally, one who employs an independent contractor is not liable for the independent contractor's negligence․” Woodson v. Rowland, 329 N.C. 330, 350, 407 S.E.2d 222, 234 (1991). However, if the work to be performed by the independent contractor is either (1) ultrahazardous or (2) inherently dangerous, and the employer either knows or should have known that the work is of that type, liability may attach despite the independent contractor status. Id. at 350-51, 356, 407 S.E.2d at 234, 238. This is because, in those two areas, the employer has a non-delegable duty for the safety of others. Canady v. McLeod, 116 N.C.App. 82, 88, 446 S.E.2d 879, 883, disc. review denied, 338 N.C. 308, 451 S.E.2d 632 (1994).
Dumping of fertilizer, making tire tracks, etc..., while awful, are not inherently dangerous or ultra-hazardous, and under NC law, the landowner / employer doesn't have the liability for the contractor's negligence, I'm sorry to say. There's no "vicarious liability" that would be imputed to the landowner in this regard. You'd have to show that the owner actually did something negligent, that was foreseeable beforehand, that actually caused the harm. Negligent hiring would not work unless you could show that the same type of harm had occurred before AND the owner knew or should have known of that probability of harm. So unfortunately I don't think that you would have a case against your neighbor, but only against the contractors.
I know this is probably not what you wanted to hear, but it is the law. I hope that clears things up anyway. If you have any other questions, please let me know. If not, and you have not yet, please rate my answer AND press the "submit" button, if applicable.
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