According to Section 5511 of the Pennsylvania Code, it's against the law to abandon an animal under the state's cruelty to animals statute.

Abandonment includes depriving an animal of necessary sustenance, which given the age of the kittens abandoned on the Broad Mountain, particularly the younger ones, was clearly what happened in this situation. It also includes depriving the animal of shelter, veterinary care or protection from inclement weather.Fines and penalties could be even greater in this situation since not only were the kittens abandoned, they were "placed in imminent risk of serious physical harm" since they were left near a heavily wooded, busy highway and could have wandered into the roadway and been struck by a passing vehicle or maimed or eaten by a predatory animal.The person who abandons an animal could be charged with a summary offense, but since the kittens were left in imminent danger, the act could include aggravating circumstances, which could make it a third-degree misdemeanor.The fine if convicted of a summary offense could run from $50 to $750 and/or up to 90 days imprisonment, or both. The penalty for a third-degree misdemeanor could be much greater.