Answer:
Moral ethical obligation
Explanation:
He is morally obliged to report the findings to the authorities in order to protect the community from any impending hazard caused by the discharge into the water body.
Under ethics after any future investigation is carried out and he was found out to have carried out analysis, he might be penalized for conspiracy to conspire even if he states categorically that his contract was terminated by xyz for proofing otherwise. This might lead to serious consequences for him.