No agricultural operation shall be found a public or private nuisance as a result of changed conditions in or around the locality of the agricultural operation, if such agricultural operation has been in operation for one year or more and if it was not a nuisance at the time it began operation. This section shall not apply when any aspect of the agricultural operation is determined to be injurious to public health or safety under N.H. Rev. Stat. § 147:1 or N.H. Rev. Stat. § 147:2.