Somewhere in the centre of Vietnam, roughly halfway between Hanoi and Saigon, lies the small province of Quang Tri. Palm trees line its white-sand beaches, water buffaloes lounge in its many ponds and farmers bring harvests home in ox-drawn carts.

It was here, at around 10am on one sweltering hot morning in 1988, as Nguyen Dinh Thu was hoeing the small piece of land his parents had given him, that he struck the unexploded US military bomb that had lain undisturbed there for 15 years. Nguyen had no knowledge of this, or the 11 other bombs that were later dug up from the ground on which he'd been standing.

Quang Tri is a poor province now and was poorer in 1988. In the absence of an ambulance or any available taxi, Nguyen's friends and relatives had no choice but to carry him the 25km to the nearest medical facility in a hammock. It was here, some time later, that Nguyen, a farmer in a developing country, came round to find both his hands had been blown off –his right at the wrist and his left halfway down his forearm – and his face and legs were riddled with shrapnel which will stay inside him permanently.

The Vietnamese government estimates that around 14m tonnes of ordnance, nearly three times that used by the Allies in the second world war, was dropped on Vietnam between 1959 and 1975. Between 10% and 30% of it failed to detonate. According to the most recent official figures, explosions caused by buried bombs and mines claimed around 105,000 civilian victims between 1975 and 2007. In total, the Vietnamese government estimates that around 15% of the total surface area of the country is contaminated by unexploded ordnance (UXO). For Quang Tri, nestled as it is on the wartime division between what was North and South Vietnam, that contamination is closer to 84%. What that means for the families in its many farming communities is that a war they did nothing to start and knew little about has never really ended.

For Le Van Tra, the technical operations co-ordinator for the Mines Advisory Group (MAG) in Quang Tri, this legacy of war is an everyday fact of life. Le Van has been working for the group for 13 years. He and his colleagues investigate the unexploded bombs located by the group's community liaison teams and work out how to make them safe. If Le Van's knowledge of the ordnance found on the ground in Quang Tri can sometimes appear to border on the psychic, it's because it's had to be. Before working for the mines group, he was one of many people – untrained and uneducated in the workings of unexploded bombs – who trawled the forests and beaches of Quang Tri hunting for the metal casings that could be traded for scrap. It's an activity both illegal and lethal, but for many in the poor and isolated regions of Quang Tri, the 25,000 Vietnamese dong ($1) a shell casing can fetch is tempting.

Given the nature of the work, accurate casualty figures are impossible to come by, but they're high. "My wife and family were scared," Le Van explained. "They knew that a lot of scrap metal collectors were being killed, but there was a lot of UXO to be found then and scrap metal collecting, for many, was just another part of farming." But for every piece of ordnance found came the risk of another explosion, and it was with relief as well as pride that Le Van's wife and family greeted his decision to join the mines group.

It's early in the morning at one of MAG's field offices in An My village. Already, most of the adults are at work in the fields, bringing in this year's harvest. Like everywhere in Quang Tri, the scene is an idyllic one: there's no sound but that of the birds and the rhythmic beating of breakers on the nearby shore. Conical-hatted farmers work away in rice paddies as has been done for centuries, and 12-year-old Duong Ba Tien wants to show the MAG team one of the bombs he's found. Duong doesn't know how long it's been there or even how it got there; it's where he grazes his family's water buffalo.

His father has told him not to go near it. A 13-year-old boy was killed in An My by an unexploded bomb four years ago as he played in his garden, and the shock waves still reverberate through this tiny community. Duong's bomb is a big one, Le Van explains; it has the capacity to level everything within a 150-metre radius, with shrapnel extending its killing range by a further 350 metres.

Le Van, with the confidence of a surgeon outlining a particularly tricky procedure, kneels down beside it to explain how the rust has made the detonator in this particular piece of ordnance unstable.

Removing the unexploded bombs, as well as the other items the MAG expects to find in An My, will leave this land safe for Duong, his family and the families of many others throughout the village, as well as removing a shadow that's been hanging over An My for the last 37 years.

This is a benefit that Nguyen is well aware of. It's now 24 years since the bomb blast that took his hands and the mines group has cleared his small, 500 sq m piece of land. Roots of Peace, another NGO, will shortly plant pepper trees, providing Nguyen, his wife and two young children, with a livelihood that a forgotten bomb took away from them all those years ago.

Nguyen's voice cracks as he describes the difference the NGOs' work will make to their lives. At last, he has land. At last, he can support his family. He has no grievance, he explains, against the Americans who caused a war and left the consequences to the Vietnamese people. He's just grateful to have his land.

Nobody is sure how many unexploded mines and bombs lie beneath Vietnam's picturesque landscape. The government predicts the cleanup work may go on for a further 100 years. In the meantime, farmers and their families will continue to pay the heaviest of costs, in terms of both lives and land, for a war that few of them will ever understand.