Virgin sand may be added to the salvaged sand as needed and when {HEAD ~ virgin sand} is added to {TAIL ~ the salvaged sand}, the term the salvaged sand before kneading should be broadly interpreted to include mixture of the salvaged sand and the virgin sand 
is added to
Virgin sand may be added to the salvaged sand as needed and when { HEAD ~ virgin sand } is added to { TAIL ~ the salvaged sand } , the term the salvaged sand before kneading should be broadly interpreted to include mixture of the salvaged sand and the virgin sand
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH