Gyong La, Yarma La (6,100m), and (5,800m). Pakistan controls the glacial valleys immediately west of the Saltoro Ridge. According to TIME magazine, India gained over in territory because of its 1980s military operations in Siachen. In February 2016, Indian Defence Minister Manohar Parrikar stated that India will not vacate Siachen, as there is a trust deficit with Pakistan and also said that 915 people have died in Siachen since Operation Meghdoot in 1984. According to official records, only 220 Indian soldiers have been killed by enemy bullets since 1984 in Siachen area. India has categorically stated that India will not pull its army from Siachen until the 110-km long AGPL is first authenticated, delineated and then demarcated. The 1949 Karachi agreement only carefully delineated the line of separation to point NJ9842, after which, the agreement states, the line of separation would continue "thence north to the glaciers". According to the Indian stance, the line of separation should continue roughly northwards along the Saltoro Range to the west of the Siachen glacier beyond NJ9842; international boundary lines that follow mountain ranges often do so by following the watershed drainage divide such as that of the Saltoro Range. The 1972 Simla Agreement made no change to the 1949 Line of Control in this northernmost sector. Drainage The glacier's melting waters are the main source of the Nubra River in the Indian region of Ladakh, which drains into the Shyok River. The Shyok in turn joins the 3000 kilometre-long Indus River which flows through Pakistan. Thus, the glacier is a major source of the Indus and feeds the largest irrigation system in the world. Environmental issues The glacier was uninhabited before 1984, and the presence of thousands of troops since then has introduced pollution and melting to the glacier. To support the troops, glacial ice has been cut and melted with chemicals. Dumping of non-biodegradable waste in large quantities and the use of arms and ammunition have considerably affected the ecosystem of the region. Glacial retreat Preliminary findings of a survey by Pakistan Meteorological Department in 2007 revealed that the Siachen glacier has been retreating for the past 30 years and is melting at an alarming rate. The study of satellite images of the glacier showed that the glacier is retreating at a rate of about 110 metres a year and that the glacier size has decreased by almost 35 percent. In an