Final payments totaling about $100 million are going out to states as their share of 1990 national forest sales receipts, the Agriculture Department said Friday. F. Dale Robertson, chief of the Forest Service, said the money is in addition to a preliminary payment of $246 million which went to the states on Sept. 19, bringing the total for the fiscal year that ended on Sept. 30 to more than $346 million. By law, 25 percent of the revenues collected by the Forest Service for the sale of timber and other use of national forest resources must be returned to the states where the forests are located. Actual receipts in fiscal 1990 totaled $1.38 billion. The states are required to use the funds for schools and roads. Oregon is the biggest recipient of total forest receipts for 1990 with $150 million, followed by California, $64 million, and Washington, $37 million.