Warsaw — A quiet exodus is under way here. Some 1,400 former Solidarity internees and other opposition activists have resettled in the West since Polish military authorities offered them passports for emigration about a year ago.
It is difficult to establish exactly how many have left, or how many more may be waiting to go. Not only are there discrepancies between Western and Polish figures, but also the emigrants who have already left this country have scattered among some six or eight Western nations.
A US State Department spokesman said last week that between 300 and 400 former internees are now in the United States. When family members are included, the total comes to some 1,150 people. More than 1,000 other former detainees and their families have gone to Canada, Australia, and West European countries.
When Gen. Wojciech Jaruzelski offered early last year - shortly after martial law was imposed - to let internees emigrate, many Poles were scornful. They saw it as a move by the authorities to rid themselves of uncomfortable and in most cases uncompromising opponents.
Few prisoners elected to avail themselves of the opportunity. And neither the US nor most other Western countries displayed any hurry to accommodate would-be emigrants.
Canada and Australia were the first to open their doors. Among West Europeans , France led the way. Then the US and other European countries followed suit.
As 1982 went on, more and more internees - men and women who had made clear they could not compromise or reconcile themselves with the crackdown on Solidarity - decided to take advantage of the option. Some were given short furloughs from detention camps so they could lodge visa requests for immigration with embassies here.
Following the initial lag, an agreement between the Reagan administration and the West German government made resettlement in the US possible for Poles looking for political asylum. Under US law a request for political sanctuary cannot be accepted while a person is still in his own country. A would-be immigrant must first get to another country.
Thus the agreement with West Germany established a transit point there for Polish emigrants, with the US refugee processing center at Frankfurt determining their status and arranging for their journey to the US. ''West Germany takes them first, and then we can accept them as political refugees,'' a US official here said.
He stressed there is no agreement between the US government and Polish authorities regarding emigration. The procedure is based entirely on the agreement with Bonn and involves the embassy in Warsaw, a Geneva-based intergovernmental committee for migration, and private sponsors.
At the end of April a senior official of the Polish passport department said 2,020 requests for emigration had been made, involving a total of 5,436 persons. Some 4,480 of those people had already received affirmative replies, and the rest were still under consideration.
The official said that 1,571 Poles - including 522 ''opposition activists'' and their families - had already left Poland. He went on to repeat a propaganda point made frequently here: Many departures were delayed by difficulties created by Western governments over visas and by the highly selective criteria they apply to applicants.
The same Polish official claimed this had led ''many'' to abandon the idea of emigration. He claimed further that Polish missions abroad were receiving more requests from emigrants wanting to return home because they were ''disillusioned'' about employment and other aspects of life in the West.
The present US program for Polish immigration is apparently ''winding down,'' although applications for another 800 individuals have yet to be completed. The flow of requests for immigration is thought to be slowing down.
The United States still seems to be the preferred destination, since so many of the internees - like other Poles - have relatives there.