The Senate completed work yesterday on a $13.9 billion supplemental appropriation bill, including money to allow an additional 1,000 Indochinese refugees to enter the United States each month.

The refugee funding steps, proposed by Sen. Rudy Boschwitz (R-Minn.), were the only major changes made in the bill during two days of Senate debate.

Under the amendment, the Senate shifted $15.6 million from U.N. technical assistance program into categories that would allow increased help for the "boat people" fleeing Indochina by the thousands.

Part of Boschwitz' amendment would increase the attorney general's refugee processing fund by some $5.8 million so that the authorized entry level of 8,000 refugees per month could be reached. As written, the bill provided for 7,000 per month.

The remainder of the Boschwitz amendment would put another $9.7 million into a U.S. emergency fund, most of which would be channeled to the United Nations for the care of refugees in camps across Southeast Asia.

Boschwitz, the son of a European immigrant, encountered little resistance to his proposal. A question was raised by Sen. Walter (Dee) Huddleston (D-Ky.), who suggested that other nations should take a greater role in refugee resettlement.

Although differences remain to be worked out with the House, the Senate-passed measure provides additional money for a variety of federal programs to continue through the end of the fiscal year Sept. 30.

The Senate rejected another amendment, offered by Sen. S. I. Hayakawa (R-Calif.), to cut $188.7 million from the food stamp program, for which the bill provided $988.7 million more. The vote was 62 to 28.

By a 67-to-24 vote, on a resolution offered by Sen. Roger W. Jepsen (R-Iowa), the Senate went on record expressing the view that the Department of Health, Education and Welfare should borrow from its next fiscal year funds to avoid a cutoff next week of some Medicaid and welfare payments to the states.

HEW said last week that it would have to reduce payments during the next quarter by $831 million to meet the spirit of the so-called Michel Amendment, which last year ordered HEW to cut spending by $1 billion because of waste, fraud and abuse in some programs.

Jepsen and others contended that HEW's failure to comply with the directive offered by Rep. Robert H. Michel (R-Ill.) was a "contemptuous" disregard of bonafide recipents of Medicaid and Aid to Families with Dependent Children.