WASHINGTON a week ago issued new regulations governing the entry of immigrants into the United States.These stem from the passage last fall by Congress of the first comprehensive bill governing legal immigration in 25 years. The 274-page measure was welcomed by business since it opened the door somewhat wider not only to the "huddled masses yearning to be free," as stated on the pedestal of the Statue of Liberty, but even more to the educated, skilled, and moneyed. Coming into effect Oct. 1, the law permits a total of 700,000 immigrants annually in 1992, 1993, and 1994, and 675,000 a year thereafter. That's up from 500,000 a year. Within the 700,000 new immigrants, 465,000 will be relatives of either American citizens or permanent resident aliens. The number of visas allotted mostly to high-skill professionals such as researchers, engineers, scientists, and others with advanced degrees, "exceptional ability," or special skills in short supply in the US will be incr eased from 54,000 to 140,000. "There is a lot of talent around the world and we need to use it," says Phyllis Eisen, an immigration expert at the National Association of Manufacturers. "We need to bring in those skills that are needed. It is long overdue that Congress, in this bill, took into consideration business concerns. We think immigration is good for this country." Some of the new talented immigrants, she adds, will help American business maintain a "competitive edge," creating jobs in this country for those with less skills. The admission of the new immigrants will not do much to relieve developing country population pressures. The world is adding around 100 million people a year. Even if refugees (not counted in the 700,000) and illegal immigrants bring the total number of new entrants into the US to 1 million per year this decade, this would amount to only 1 percent of world population growth. Nor will the "talented" immigrants be numerous enough to relieve the US of the need to improve the education and training of its people. "Immigrants will only be a modest supplement or complement," says Rick Swartz, who was founder of the National Immigration Forum, a coalition of pro-immigration groups that helped shape the new legislation, and who is now a Washington consultant. "We are really not talking big numbers." The 140,000 visas open for the "brainy" and skilled shrinks quickly because that number includes their families - about 1.5 members on average per primary immigrant. The number also includes 10,000 visas for investors who plow at least $1 million into the economy and create 10 full-time jobs or who invest $500,000 in targeted areas. Another 10,000 visas will be given to "special immigrants" such as ministers and religious workers. So it boils down to about 55,000 to 60,000 visas for the talented immigran ts sought by business. Moreover, those companies seeking to bring in immigrants or temporary employees to fill various job slots will have to jump through "more technical hoops," as Warren Leiden, executive director of the American Immigration Lawyers Association, put it. The new law requires more "attestations" that the new employee is being paid the "prevailing wage," or that a genuine effort has been made to find an American for the slot, or that the individual meets other requirements. Mr. Leiden expects the 3,000 lawyer members of his association to get more business from the new legislation. If, for instance, a firm sponsors a project manager or engineer to get a new assembly line launched, and somehow violates the rules, the penalty could be denial of the right to bring in anyone else for a year. The result, Leiden speculates, could be a long delay in getting the project going. There is also a question of whether the bureaucracy will be able to grant the new visas for immigrant tale nt expeditiously. None of the agencies involved have been given extra help to handle the anticipated extra work. "We have no increase in personnel," notes an INS official. Nonetheless, the bill is significant to the US. It means an even greater variety among its citizens. It means more money flowing abroad as remittances. An estimated $400 million to $700 million per year go to El Salvador alone. Despite a low birthrate among native-born Americans, the additional influx of immigrants will maintain a growing US population.