EDMUND KEELEY'S new book appears to be the first widely distributed novel to try to deal with the events which have taken place in Cambodia since 1975. For whatever reasons, the enormity of what has happened there over the past decade -- the death by execution and starvation of much of the country's population and the annihilation of its ancient traditional culture -- has been virtually ignored here. This silence is all the more striking if one thinks of the four uninterrupted decades of memoirs, dramatizations, histories and philosophical interpretations that have followed the genocidal atrocities of the Nazis.

Given unexploited historical subject matter as emotionally charged as this, no competent novelist who had done his homework could fail to produce a work which would startle and disturb its readers. Edmund Keeley is more than a competent novelist, and A Wilderness Called Peace certainly is disturbing to read, but the book fails, perhaps because the full implications of its subject are beyond the range of Keeley or any other novelist now writing in English.

In gathering material for the novel, Keeley spent time on the Thai-Cambodian border and in Bangkok, speaking with such experts as John Crowley, who played a critical role in the Cambodian rescue effort; Tim Carney, whose photographs manage to capture the refugee tragedy at full force; and relief personnel working right in the border settlements. What he learned lends itself far more to the methods of reportage than to those of responsible fiction. As no westerners who remained in the country after the evacuation of the French Embassy at the end of April 1975 are known to have survived, to brig the events to life, Keeley had to create Khmer characters who could remain in the country after the last non-Khmers were evacuated by the Khmer Rouge from the detention center at that embassy.

Keeley attempts to solve this problem by putting the novel's major revelations into the mouths of two extremely westernized Cambodian characters. Chien Fei, a sophisticated and highly educated (in France) woman of Chinese-English-Khmer extraction contributes the most affecting portions of the book: journals she keeps in the form of extended letters to past lovers, one American, one Khmer. She has changed her name to the properly Khmer Phal Sameth to save herself from the penalties inflicted by the Khmer Rouge on the detested Chinese ethnic minority. A similar journal/letter sent back to her by Tan Young, her Khmer confidant and lover who has resettled in the United States, provides the second Khmer viewpoint.

But Sameth, the only fully projected character in the novel, is far too western a presence to be creas someone who has survived for months under a regime which had as one of its primary policy objectives the extermination of all intellectuals, especially those who had been educated abroad. There is just no way the reader can willingly suspend disbelief to the point of accepting Sameth as a fake peasant, enduring forced marches and slave labor and passing undetected as others are executed around her. In the initial months of the regime, she spends considerable time writing -- in English! -- in her journal, which she clearly directs to an American ex-lover who had been in Phnom Penh with the State Department, and manages to keep the book with her until she escapes over the border into Thailand.

Sameth reveals the extent to which she has abandoned her native traditions on the novel's very first page:

". . . I think (this inelegant little notebook) will most likely go with me into my next incarnation unread by you or anyone else, and since I'm sure that I will appear among the lower orders of life -- at best as a careless scavenger of a bird, at worst as a tick to suck your blood -- even I will not be able to read it after the road ahead turns back on itself. And that too is a certain liberation.

"You didn't know I had such Buddhist leanings, you didn't take them seriously . . ." No Buddhist, regardless of how liberalized in his or her thinking, would throw off such remarks about reincarnation further down on the evolutionary scale. To do so is to curse oneself to such a rebirth, and this is a very different matter from the westerner's, "Well, I'll be damned." Sameth has evidently been away for a long, long time.

NEVERTHELESS, whatever strengths Wilderness possesses are in the sections written by Sameth, which permit Keeley to incorporate a good deal of reportage. Her account at the end of the book of life in Vietnamese-occupied Phnom Penh is fascinating and -- if Keeley's accounts of the Khmer Rouge takeover and of conditions along the border during the refugee exodus can be taken as representative of his reliability -- accurate. (One curious lapse: Sameth and the new lover she meets in the occupied city walk on the "riverbanks" of the Tonle Sap. The Tonle Sap is not a river, but a large lake many miles distant from Phnom Penh.)

The bulk of the novel, into which the Sameth portions are set, is far less satisfying, and its main failures are in the area of characterization. Thirith, the young woman Sameth inherits from a couple who die during the Pol Pot years and raises as a daughter, is a stock character: a fiercely idealistic teen-ager who sneaks off to join the Khmer Serei insurgency. Tan Yong, the Khmer confidant to whom Sameth directs one of her extended journals, is articulately and confidently western in a way his stated journalistic background does not account for. He and Sameth correspond, implausibly, in an English style that would have amazed Henry James: "To say your name again to myself in private with an assurance you are still alive," Tan Young writes to Sameth, "to know that it is not merely a sort of exclamation that signals my hopelessness about ever seeing you again as it so often did during the past five years, this is in any case enough pleasure from the sound and shape of it to fill the moment."

American characters fare even worse. Tom Macpherson, the State Department officer who had been Sameth's lover, and his disaffected son Tim, who sets off for Southeast Asia to straighten out the mess his father and others had made, never come to life at all. The crooked politician Polk, who also makes it from Foggy Bottom to the border to become involved in covert arms supply to the Khmer resistance, is a malefic shadow of the sort usually encountered in television spy dramas.

Obviously missing from this novel of Cambodia in extremis is a truly Cambodian perception. Khmer friends of this reviewer complained after seeing The Killing Fields, a film which covered some of this same territory, that it conveyed the impression that its hero Dith Pran had been somehow ennobled by his contact with westerners. They felt that the film implied that his interaction with westerners gave him access to insights which escaped his fellow countrymen, who were shown suffering like animals. A Wilderness Called Peace, unfortunately, reinforces this impression. The book brings the reader no closer to the feelings of Cambodians who saw one of the most horrifying political transformations in all of history invade and destroy their lives within the course of a few years. Before we can attempt to understand their experience, we will have to wait for Cambodia's survivors to begin forging it into a literature of their own.