A PERSON REGISTERED IN GST IS DOING BUSINESS OF BLASTING AT CLIENT'S SITE. FOR THIS PURPOSE HE SENDS EXPLOSIVE GOODS FROM HIS GODOWN TO THE SITE ON ESTIMATED BASIS. AFTER COMPLETION OF THIS WORK, THE LEFTOVER GOODS SENDS BACK TO THE GODOWN. MY QUERY IS THAT DOES HE NEED TO GENERATE EWAY BILL, WHILE SENDING GOODS TO SITE AND RETURNING FROM SITE? PLEASE GUIDE