Sentence:  The Secretary of the Interior shall submit a report of his findings , together with recommendations for an <WSD>effective</WSD> safety program for metal and nonmetallic mines ( excluding coal and lignite mines ) based upon such findings , to the Congress not more than two years after the date of enactment of this Act . 
Meaning of the word marked with <WSD> tags:  producing or capable of producing an intended result or having a striking effect