We learned a lesson from this tragedy: namely, the enormous role that support from neighboring local administrations and industry associations involved in human waste disposal can play at evacuation shelters.

Another challenge we face is upgrading ageing sewage treatment facilities. The number of accidents occurring due to ageing sewage pipes started to increase in the mid-1970s. Today, the number of accidents per year is steady at somewhere between 4,000 and 6,000 per year.

Furthermore, a significant portion of the world's population still suffers life without appropriate treatment of drinking water or sewage water, causing serious environmental and hygiene-related problems. Japan's water treatment technologies and systems are highly praised around the world and have spread to countries around the globe (see below). Three Japanese companies together account for nearly 50% of the global market share for technologies such as Reverse Osmosis filtration (RO, for desalination of seawater and producing reclaimed water) and Nano Filtration membranes (NFs, used primarily for water purification). In addition, local governments that have experience with large-scale systems are vigorously expanding their sewage treatment businesses in overseas locations in cooperation with major companies.

However, it is not always possible to maintain sustainable water resource management by simply “transplanting” the technologies and systems to particular areas. Cultivating and maintaining an attitude of taking good care of the things around us—even if they are trivial—allows us to maintain a good environment in our daily lives. In addition to Japan’s advanced technologies and systems, it may be useful to spread this attitude to countries working to achieve sustainable societies around the world, thereby creating a “beautiful” global environment.

Business Trends in Overseas Rollout of Water Supply and Sewerage Systems by the Private Sector and Local Government

China	Vietnam	Mongolia	Malaysia	Saudi Arabia	Mexico	Overall activities
Local government	Kawasaki City Nagoya City Kyoto City Kitakyushu City Sapporo City Saitama City Chiba City Yokohama City Fukuoka City Tokyo metropolitan area	○○○	○○○	○	○	<nl>

Note: 2008 performance, amount-based figures, values estimated by Fuji-Keizai

Source: Ministry of the Environment based on the Fuji-Keizai Current Situation and Future Perspective of Water Related Business

2009 Edition and Japan Global Center for Urban Sanitation (GCUS) website.

## (5) Mining of Underground Resources and Sustainability

## a) Limited resources

Various metal resources are used for products around us (Figure 1-3-19). For example, iron is used for car bodies, copper for lead power lines, zinc for preventing corrosion, and lead for storage batteries. Our present convenient life is realized by consumption of these metal resources.

Hardly any of these metal resources are mined in Japan, so Japan depends on imports. For products in Japan, about 130 million tons of iron ore are imported, about 5 million tons of copper ore, about 1 million tons of aluminum ore, and about 1 million tons of zinc ore. Thus, Japan is one of the world's metal resource importing countries.

There are limits to the places where metal resources can be mined and the quantity of production. The US Geological Survey has calculated the following reserves/production ratios as of 2010: 66 years for iron ore; 40 years for copper ore; 21 years for lead ore; and 21 years for zinc ore. Although the reserve/production ratio can be extended due to price hikes or tight demand, that for iron ore, for example, was 166 years in 1990: in the past 20 years, its reserve/production ratio has become one-third of what it was. Focusing on gold or silver, the amount of resources that have been mined (terrestrial resources) is more than the reserves of resources confirmed to date (underground resources): 93,000 tons for terrestrial resources of gold and 42,000 tons for underground resources of gold; 630,000 tons for terrestrial resources of silver and 270,000 tons for underground resources of silver, estimated as of 2004 (Figure 1-3-20).

The quality of ore is declining. In general, mined ore in the depth tends to be lower in quality than that under the surface. Recently, most of the mining process has already

Figure 1-3-20 Main Terrestrial Resources and Underground Resources (% refers to the ratio of terrestrial resources)

Figure 1-3-21 Global Crude Steel Production and Iron Prices (dollars)

Data Source: World Steel Association (crude steel production), Purchasing Magazine (iron prices)

Note: Iron price is given as the annual average market price in the American market.

Figure 1-3-22 Global Copper Consumption (Unprocessed Metal) and Copper Prices (dollars)

Data Source: World Metal Statistics (copper consumption), LME settlement (copper price)

Note: Copper price is given as the annual average market price in the London market.