The Apsara National Authority (ANA) is repairing three more Buddha statues at Angkor Wat’s “Bakan tower”, the central tower-like spire and one of the most iconic features of the ancient temple.

Experts at the Department of Temple Preservation in Angkor Park say the repairs could take five months or more.

Soy Sophearin, technical officer of the ANA’s Department of Conservation of Monuments and Preventive Archaeology, said the restoration project of the Buddha statues began early this month.

According to the ANA, the project to renovate the statues was financially supported by Seang Chanheng, director-general of Heng Development Co, Ltd. Last November, ANA sculptors completed the restoration of a dilapidated Buddha statue in the south corner of Bakan tower.

Sophearin said the damage to the statues was due to natural factors. The urine of nesting bats created a humid environment, and the moisture and salinity of the environment affected the statues. The department’s team was replacing netting which would prevent the bats from roosting inside the statues.

He added that the three Buddha statues were made of stone, which the ancients had posted on the four gates of Angkor Wat as gestures of immunity. The statues are at high risk because they were losing their protective slate coating.

“It’s not just on the body of the Buddha, the coating is peeling away from the plinth that the statues are mounted on, and the more the statue and plinth are exposed, the more rapidly they deteriorate,” he said.

He said the repairs are designed to prevent the slate from peeling off the stone, while finding a way to replace the slate that had already fallen away. The slate is attached with a mortar – which is beginning to decay – so experts must discover how to prevent the mortar from continuing to decompose.

He said there are two layers of discolouration. The first is black and the second is red. Some parts were originally covered with gold, but the gold almost entirely been peeled off. Now the team is cleaning the statues where they are stained by smoke – from candles and incense – and bat urine.

“The black is mostly caused by smoke damage, but because the stains are so deep, we must clean them very carefully,” he said.

The official suggested that the timetable for restoration may be unrealistic, because this work requires a lot of patience and careful colour matching to achieve the look of the original.

“We cannot set an exact deadline because these statues date from the 15th century. If we approach this task with too much haste, we may undo the good work we have already carried out,” he added.