Mortuary Service Administration Act Article 30

Ownerless graves in public cemeteries or other publicly owned land in the area of the special municipalities, counties (cities) or townships (towns, cities) competent authorities shall be cremated or have the ashes (skeletons) deposited in ashes (skeletons) storage facilities after a three-month announcement and when disinterment is determined necessary.
中文原文 殯葬管理條例第30條
直轄市、縣(市)或鄉(鎮、市)主管機關對轄區內公立公墓內或其他公有土地上之無主墳墓,得經公告三個月確認後,予以起掘為必要處理後,火化或存放於骨灰(骸)存放設施。

English translation for reference only; the Chinese text prevails. Not legal advice.