Sen. Robert Dole (R-Kan.), continuing his attack on tax leasing, yesterday disclosed that public transportation companies received very low rates of return when they sold tax breaks last year to General Electric Co. and Metromedia Inc.

"Through the unintended generosity of so-called safe harbor leasing provisions, profitable companies and middlemen have made millions of dollars in leasing deals with federally funded public transportation companies," said Dole, the chairman of the Senate Finance Committee.

The two deals examined in a study by the Joint Committee on Taxation were the sale of tax breaks on $98 million worth of commuter rail cars and buses by the New York Metropolitan Transit Authority to Metromedia Inc.; and the tax benefits on $215 million worth of locomotives, rail cars and track improvements sold by Amtrak to General Electric.

The tax benefits in the Amtrak deal were worth, according to the Joint Committee, $87 million. Of this amount, $54 million, or 62 percent, went to Amtrak and $33 million, or 38 percent, went to General Electric. In the MTA deal, the value of the tax breaks were determined to be $15.5 million. Of this, $1.4 million, or 9 percent, went to Citibank and others acting as middlemen in the deal; about $4.5 million, or 30 percent, went to Metromedia, and the remaining $9.6 million, or about 61 percent, went to the MTA.

Citing the relatively small percentages received by MTA and Amtrak, Dole said the transactions "were even less efficient than the private-sector leasing deals which many critics are calling scandalously inefficient. This latest tax leasing horror story should remove any doubts that the intent of safe harbor leasing has failed."

The Joint Committee, in a study of 1981 lease deals, found that in the average case, 76 percent of the revenue lost to the federal government went to the target group of marginal, non-taxpaying companies. Of the remainder, the committee found that 22 percent went to profitable firms that bought the tax breaks and two percent went to lawyers, brokers and others who arranged the deals.

The 1981 tax bill allowed companies to buy and sell tax breaks on new investments through paper transactions called "leases." The provision has become highly controversial as a result of disclosures of benefits flowing to highly profitable firms, and Dole has threatened to repeal or severely restrict the practice retroactive to Feb. 19.

"We can't expect Congress to cut back food stamps, medicaid and other social programs while corporations and other third parties profit from the unintended benefits of safe harbor leasing," Dole contended.