China has released an ambitious plan to make 90 per cent of its polluted agricultural land “safely usable” within four years, as it addresses a longtime problem that affects food security and public health. A survey published in 2014 estimated that 20 per cent of China’s arable land was contaminated by decades of unregulated metal smelting, mining and fertiliser manufacturing. The clean-up bill could reach $1tn, by some estimates. While Beijing has promised to tackle soil pollution for some time, it originally planned to do so after addressing the more visible problems of air and water pollution. However, experts have realised that contamination leeching into the soil from abandoned industrial sites will continue to undermine water quality unless tackled at the same time. Greenpeace soil pollution expert Ada Kong lauded the “pragmatic” proposal. “It’s not a realistic plan to have perfect soil in the country, but just to take steps to ensure the contamination won’t lead to major problems”. A second, more detailed survey to pinpoint where the pollution hotspots lie and identify the worst sources is to be completed by 2018. That information was not in the publicly released version of the 2014 survey, which was based on soil samples collected evenly across the nation. Chinese soil experts are divided over the best approach to soil pollution, ranging from the cheapest method of simply not growing edible crops on polluted land to the intensive digging, burning and disposal of contaminated soils from toxic urban industrial sites. Most experts are concerned that improper disposal and other shortcuts could simply spread the problem around. The plan did not specify what methods would be used. Ground pollution is a sensitive topic, with residential neighbourhoods and villages often built in proximity to toxic sites. Local bureaucrats are reluctant to acknowledge the worst sites for fear of compensation claims by sick residents, destroying property values and ruining the market for their agricultural produce. This year reports of nausea and nosebleeds among students at an elite school in Changzhou, an eastern industrial city, led to media revelations that the school’s new campus had been built next to an abandoned pesticides factory. The action plan includes better provisions for disclosing data on soil quality, including a national online platform. It calls for greater penalties for polluters and for mishandling of dangerous chemicals, a problem that grabbed international attention after an explosion at a chemicals warehouse wiped out an industrial and residential neighbourhood in the port city of Tianjin.