Solatium hurdle to AAI Sikkim airport project

Kolkata: An attempt by Airports Authority of India to fix landslides on the hill slope along Sikkim’s Pakyong airport runway by undertaking a mountain stabilization project has run into rough weather with residents refusing to allow work till their demand for compensation of nearly Rs 250 crore is met.
The project is critical for safety of flight operations at the airport, particularly during monsoon, when landslides could lead to desposition of earth and rubble on the runway.The project is also necessary to increase the clearance between the runway and the hill slope from 40m to 75m to let ATR aircraft operate from the airport. At present, only Q400 Bombardiers, that have a shorter wingspan, can fly into Pakyong.
“Pakyong airport’s runway, half of which is carved out of a hill and the rest created by levelling the hillside leading to the valley, is designed for category 3C aircraft. To enable all such aircraft to operate, we need to stabilise the hill slope and strengthen the bottom reinforcement wall. Work on the latter for Rs 25 crore has started, but the Rs 105-crore slope-strengthening work has been held up. We have approached the Sikkim government for early resolution,” said AAI regional executive director S P Yadav.
Strengtening the bottom reinforcement wall involves drilling piles into the hill side. While both projects were to be completed by year-end, sources said the job, requiring nine months, was unlikely to meet the deadline as Sikkim gets heavy rain from mid-May to September-end.
Locals who lived at Upper Dikling village on the hill before the airport was built and who still own farmland there, have refused to allow the stabilisation work till they are compensated. They feel compensation will never be paid if they let the work proceed.
Sources said 60 people had initially claimed compensation, but the number has swelled to nearly 200, with regular reports of subsidence, sliding of earth and cracks. For two years, the state government has paid Rs 76 lakh in crop compensation, but residents now want to be compensated for the land they say is no longer fit for farming.
The civil aviation ministry had earlier paid Rs 64-crore compensation to rehabilitate the 60-odd families residing atop the hill following an MoU between the state and the Centre. “Thereafter, everything was to be taken care of by the state government. Now, there is a fresh demand for compensation. The airpo-rt director and state chief secretary will meet to find a sol-ution,” another source said.
SLIPPERY SLOPE
* Pakyong airport, inaugurated by PM Narendra Modi on Sept 24, is situated at a height of 4,500ft
* About 200,000sq m of hills had to be shaved off to get a flat and even surface for the airport with a table top runway
* Heavy rain, heavily weathered ground conditions, high seismicity, balance of cut and fill and land availability constraints made the 9yr project extremely challenging
* The reinforced soil structure, that serves as a retention embankment for the runway, is one of the world’s tallest reinforced structures (almost 80m)
* To make level ground for airport construction, the mountainside slope up to around 110m high had to be excavated and the valley side slope required retention structures up to 74m high
* Due to the geology of the site (a mix of sedimentary and metamorphic rocks that are highly weathered), the design was challenging
* The structure also had to deal with very high seismic loading and 4-month monsoon period with one of the world’s highest annual rainfall (about 2,500 mm)