Monarch Quarry

I understand that most mining and quarry operations do not completely cease, because the owners would then have to do some expensive enviornmental restoration. Does anyone know the circumstances of the DRGW discontinuing service to the Monarch Quarry. Did the volume diminish that quickly that the railroad could not justify continuing operations or did the quarry switch to trucking their product. You can still see some loaders and trucks at the quarry, but I have not seen any serious activity at the quarry in years. Does anyone know if they are moving anything out of the quarry today.