TRADING OF PEFC CERTIFIED SAWN TIMBER AND SAWMILL WASTE (SAWDUST, OFF-CUT, WOOD-CHIPS, BULK, WOOD SLAB) AND WOOD PELLETS UNDER SECTION 6.2, PHYSICAL SEPARATION METHOD AND IMPLEMENTED BASED ON APPENDIX 1 PEFC DUE DILIGENCE SYSTEM (DDS) FOR THE AVOIDANCE OF MATERIAL FROM CONTROVERSIAL SOURCES OF THE CHAIN OF CUSTODY STANDARD