Federal policies and decisions by dairy farmers have slowed, at least temporarily, the milk-production surges of the early 1980s that led to huge government inventories of butter, cheese and powdered milk.

[Diane J. Durant] cautioned that the projections are tentative and that some authorities cite a possibility that the department will replenish its dairy surplus inventories if farmers continue to increase milk production.

According to the department's Commodity Credit Corp., which controls the government-owned surpluses, uncommitted inventories Sept. 30 included 82.3 million pounds of butter, down from 193.8 million pounds a year earlier; 98.5 million pounds of cheese, down from 558.7 million, and 63.1 million pounds of nonfat dry milk, down from 696.6 million.