A BIPARTISAN effort has begun to repeal a five-year-old law that levies harsh penalties on employers who hire undocumented workers.Congress members who are backing the appeal acknowledged last week that they will have a tough fight. Introduction of legislation this late in the year is viewed mostly as an attempt to revive this issue. The bill's main authors - Sens. Orrin Hatch (R) of Utah and Edward Kennedy (D) of Massachusetts and Reps. Bill Richardson (D) of New Mexico and Edward Roybal (D) of California - said employer fines under the Immigration Reform and Control Act of 1986 have caused many bosses to shy away from hiring Americans who look like foreigners and who speak with accents. In addition, they said, the bill has failed to deter illegal immigration and has cost small businesses. It also has fostered a cottage industry for false documents making the smuggling of humans across the US border with Mexico increasingly lucrative. "Employer sanctions simply are not worth the price in increased employment discrimination and increased burdens on business," Senator Hatch said. A General Accounting Office experiment last year showed that, under the 1986 law, Anglos were 52 percent more likely to be hired than Latinos, even though they had nearly identical backgrounds and qualifications. The survey also found 461,000 employers who admitted discriminating against applicants because of national origin. Another 430,000 employers said they did not hire "foreign-appearing or foreign-sounding" applicants. Sen. Alan Simpson (R) of Wyoming, an author of the 1986 law, said he will "strongly oppose" the new effort to repeal its sanctions, just as the senator did last year. Under current law, employers can be fined up to $1,000 for not retaining a worker's US residency papers, and up to $2,000 for knowingly hiring an undocumented worker. The new legislation would: * Repeal the employer sanctions. * Authorize, but not finance, an increase in Border Patrol agents to 6,600 from their current 3,800. * Provide $92 million for new equipment and training for patrol officers. * Impose prison terms of up to 10 years for people who smuggle or harbor undocumented workers.