Senate Finance Committee Chairman Max Baucus, D-Mont., may seek to require some foreigners working in the United States to pay Social Security taxes and to pare back the ethanol tax credit to help offset the cost of proposed new tax credits for farmers.

The tax credits proposal, which would be added to the upcoming five-year farm bill, could cost up to $10 billion, Baucus has said. It is set for markup next week.

The measure would create a disaster trust fund to help farmers who lose crops or livestock to frost, fire, floods or drought. Some estimates peg the cost of that trust fund at $5 billion.

It also would allow farmers with land enrolled in Agriculture Department conservation programs to take a tax credit instead of a federal payment, among other things.

Under Baucus’ offset plan, about $7.1 billion would be saved over 10 years by forcing certain categories of visa holders who work in the United States but are currently exempt from Social Security taxes to begin paying those taxes.

Decreasing the 51-cents-per-gallon ethanol tax credit by 5 cents would save about $854 million over 10 years. That provision would take effect only after annual ethanol production has reached 7.5 billion gallons. Even so, that provision could irritate lawmakers from corn-producing states and senators who pushed for the current law to spur biofuel production in the heartland.

About $3.2 billion would be raised over 10 years from a change to the tax treatment of “sale-in, lease-out” deals, which typically provide tax-loss benefits to investors and brokerage firms.

His plan also would revise the tax treatment of “1031 exchanges,” real estate transactions that allow a deferral of capital gains taxes on property sales if the profit is reinvested in other property within 180 days. Baucus’ bill would bar land buyers from taking advantage of this tax break if they sell developed land and reinvest the cash in undeveloped land.