Section 29(2)(i) in Bihar Minerals (Concession, Prevention of Illegal Mining, Transportation & Storage) Rules, 2019
(i)The quarrying of sand shall be prohibited within 300 (three hundred) meters on both sides of any railway bridge or any bridge falling under any National Highway/ State Highway and shall be prohibited within 100 (one hundred) meters of both sides of any other bridge. However the prohibited zone in respect of any particular bridge may be extended by the State Government through a notification in this regard, if so required for reasons of safety.