Feng Zhiqian, project manager supervising a section of the New Erlang Mountain Tunnel, speaks with reporters, in Sichuan, Oct 12. [Photo by Ma Danning/chinadaily.com.cn]

"Every time I saw my workers staying at their posts when injured or ill, I felt guilty. But I could do little to help. Our construction project has a tight schedule."

"I felt guilty for myself too. More than two years' intensive work in mountainous areas amid extreme, humid weather impaired my health. And as with all the other workers, I live at the construction site, and only visit home four times a year at most. I have long neglected my family duties as a son, husband and father".

Speaking to reporters from Beijing covering the Ya'an-Kangding Highway construction, Feng Zhiqian, the project manager supervising a section of a hazardous tunnel through Erlang Mountain in Sichuan province, recounted the life and difficulties faced by his 450-man team.

The New Erlang Mountain tunnel, with a length of around 13.5 kilometers, is in Luding county on the border of Ya'an city and Garze Tibetan autonomous prefecture in Southwest China's Sichuan province, at an altitude of 1,500 meters.

By mid-September, construction of 5,000 meters was finished and it is expected to open to traffic in March 2018 after 65 months' work.

"The tunnel passes 13 geological fault zones and is in a seismic zone, which means it's subject to potential earthquakes or minor jolts. We reinforced earthquake resistance and built emergency escape routes after cutting new parts of the tunnel." Feng said.

According to the Sichuan transport bureau, for nine months of every year the Erlang Mountain tunnel suffers from rain and snow, which led to constant mud and landslides.

"The complex, delicate geological condition and extreme weather pose great danger to our work and slowed down our construction process." Feng said.

The current Erlang Mountain tunnel, which began construction in 1996 and commenced operations in 1999, is to the north of the new tunnel. At an altitude of 2,182 m, it is covered by snow and ice in winter leading to road closures.

The new tunnel is below the snow line and will remain open year round.

Ya'an-Kanding Highway, the first highway in Garze Tibetan autonomous prefecture is expected to be complete in 2018 and reduce the traveling time from Ya'an to Kangding to two hours from the current four.

The 135-kilometer highway has four-lane dual carriageways with a speed limit of 80 kilometers per hour.