a decision relating to the method to be used by the operator of an authorised landfill site to determine the weight of material for the purposes of landfill disposals tax
penderfyniad sy’n ymwneud â’r dull sydd i’w ddefnyddio gan weithredwr safle tirlenwi awdurdodedig i bennu pwysau deunydd at ddibenion treth gwarediadau tirlenwi