Kampuchea's Viet settlers: binding Hanoi's rule or avoiding it?

''When I first came here in 1979,'' says Y, one of the oldest Vietnamese residents in the port section of Phnom Penh, ''there were just a handful of Vietnamese here. Now there are more than 900 families.''

Y (his real name, pronounced ''ee'') is a pedicab driver. He is one of the growing number of Vietnamese who are slipping quietly into Kampuchea to make a living.

He lives in the Little Market section of this Kampuchean capital. On one side of the road are two- and three-storied shop houses, inhabited by Khmers or Sino-Khmers. On the other side, on red, sun-baked earth sloping down to the Mekong River's edge, are the Vietnamese. They now number about 4,500 in this little community.

Nearly all new arrivals, the Vietnamese immigrants live in small wooden or bamboo huts or on boats on the river.

Y paid the captain of a Vietnamese government-owned river boat 600 dong (about three months' salary at the time) to take him upriver from the Vietnamese border to Phnom Penh. The boat, he says, was full of unofficial passengers, ''mostly traders going to sell on the black market in Phnom Penh or to buy from Sisophon (in western Kampuchea near the Thai border) but also (there were) some Vietnamese born in Phnom Penh who were going back.''

In more peaceful times about 500,000 Vietnamese lived in Kampuchea. They were merchants, electricians, mechanics, restaurateurs. Outside the cities they worked in the rubber planations or, together with the Muslim Cham minority, monopolized commercial fishing in Kampuchea's great lake, the Tonle Sap. Most left in 1970, when a massacre of Vietnamese residents followed Lon Nol's seizure of power; those who clung on afterward either fled back across the border when Pol Pot took over in 1975, or perished.

Now the Vietnamese are settling in again. Vietnamese cafes and restaurants have existed here for several years. Around town you meet Vietnamese mechanics, electricians, and pedicab drivers like Y. Other Vietnamese are back fishing the Tonle Sap, running sewing shops, or driving trucks.

How many Vietnamese are in Kampuchea now is unclear. Fewer than 50,000, the Kampuchean foreign minister recently claimed; an American diplomat in Bangkok suggested the figure was around 150,000 to 200,000. US diplomats and Thai intelligence sources quoted in the Bangkok press are, in fact, warning of Vietnamese efforts to absorb or colonize Kampuchea.

Much of the evidence for these claims stems from two official documents purportedly smuggled out of Kampuchea late last year. Both lay down guidelines for the treatment of Vietnamese coming to live and work in Kampuchea. Basically the documents say that Vietnamese, both former residents and newcomers, may live and work in Kampuchea as long as they behave themselves. The documents acknowledge the sensitivity of the issue and warn against enemy ''psychological warfare to split our two peoples.'' They also speak of increasing measures to control the border and ''prohibit illegal transits.''

The documents were translated and distributed by the US Embassy in Bangkok. An embassy cable on the subject notes that the Vietnamese settlement in Kampuchea ''may be a proper subject for appropriate UN committee action.''

The same cable notes, however, that ''so far not all the ASEANs (members of the Asociation of Southeast Asian Nations) are convinced of the scope of settlement, nor aware of the PRK (People's Republic of Kampuchea) role in fostering a Vietnamese influx.'' The cable's writer speculates ''that Vietnamese impatience with the slow pace of development of PRK institutions may have caused Hanoi to opt for settlement with the goal of absorbing Cambodia if the PRK regime cannot pull itself together.''

If this is true, it should be a cause of rejoicing for Vietnam's adversaries, as nothing is more likely to inflame Khmer nationalism than Vietnamese land-grabbing. Few educated Kampucheans have forgotten that most of Vietnam's Mekong Delta was once part of the Khmer Empire.

Colonization or absorption of Kampuchea would also complement earlier claims that Vietnam was exporting slave labor to the Soviet bloc. The problem with the absorption argument is that, at least as far as Phnom Penh is concerned, the Vietnamese moving into Kampuchea seem to be trying to avoid Hanoi's authority, not impose it.

Y, for example, is a former soldier in the old South Vietnamese army. He doesn't like Kampuchean food, lifestyles, or women.

''Life here is not as much fun as in Vietnam,'' he says, ''but the economy is easier.'' He pays 25 riels a day for his pedicab - ''I hire it from a rich Khmer'' - but says he can clear 100 riels a day. ''That's 300 Vietnamese dong a day, I'd never make that much at home. Other newcomers are delighted by some of Kampuchea's special benefits: no taxes (the government still has not been able to devise a tax system), no rents, free electricity, and free water.

Some of the settlers are almost certainly dodging the draft: Two young men of military age dropped their heads and mumbled with embarrassment when asked by this reporter if they had done military service.

Even more ironic is the fact that the settlers choose to build their homes near Vietnamese soldiers' camps. ''We feel safer with the soldiers around,'' said one person, ''the soldiers do not encourage us to come, but they are happy to see us. Vietnamese like to live among their own.''

When the troops go, people here say they will think about going, too. Memories of earlier massacres are still fresh. ''I'll stay here as long as I can ,'' says Y. ''But when the last Vietnamese soldier goes, I'll go, too.''