日本水环境管理概述.doc

日本水环境管理概述木幡 邦男（Kunio KOHATA）日本国立环境研究所水土圈环境领域 领域长日本在20世纪60年代的经济迅速发展的同时也伴随着水污染的范围和程度的日益扩大和严重。这促使了中央政府采取更强有力的措施来控制水污染。水污染控制法于1970年颁布。随即，在第二年（1971），成立了环境厅，负责水环境政策，为环境保护提供一种集中监督。然而，70年代期间，由于人口增长和工业越来越集中，濑户内海周围的环境污染变成一个日益严重的问题。这种污染的后果之一是越来越频繁的赤潮现象。政府对此回应以更强硬的措施来制止水污染。1973年，颁布了濑户海环境保护临时法，并在1978年将临时法改为永久正式法。此外，1978年颁布了一系列全面长远的法律，规定濑户内海、东京湾、伊势湾和其他水体的污染物水平，这些水体中存在有机物污染重复发生的问题。后来在1984年，颁布了湖泊水质保护措施法，用来抗击淡水水域的水污染；但是，到目前为止，这些措施未能产生预期结果。目前，影响水环境的这些问题比以前更严重，而且，正如前面提到的，对策措施许多年以前就有了。2001年1月，环境厅重组为环境部。这代表日本在水污染反击战中又更进了一步。1 环境质量标准环境基本法创建了2种与水污染有关的环境质量标准：保护人体健康质量标准和保护生活环境质量标准。每种标准都创建了达到和维持公共水质量和其他水质量的政策目标所期望的水平。公共水和地下水的统一规定被颁布实施以实现保护人类健康的第一个目标。为了实现保护生活环境的第二个目标，各种水体如江河、湖泊水库、海洋和沿海地区等等都规定有与之相应的标准。公共水体根据类型进行分类在确定适用于它们的环境标准上也有所帮助。目前，就与人类健康有关的26种物质制定了环境质量标准，包括镉和氰化物总量。1997年3月，制定了地下水质量标准。与生活环境有关的环境标准，包括BOD（生物化学需氧量）标准，COD（化学需氧量）标准和DO（溶解氧）标准也已经制定。此外，为了防止富营养化，已经制定了湖泊/水库和海洋/沿海地区的氮磷水平的环境质量标准。2 排放标准规定水污染控制法确定了排放废水进入公共水体的工厂和其他商业设施的污染物排放标准。这些标准设有关于人类和生活环境的各种物质的精确浓度。到2001财年底，这些规定应用到30万个工厂和其他商业设施。此外，区域总污染负荷控制系统被用于封闭水体（海湾和内海）；该系统描述如下：3 富营养化对策3.1 湖泊水库措施1982年，针对富营养化发布了氮磷环境质量标准。国家和地方政府正在研究需要控制的物质的类别；到2000财政年度，确定了在水体中共有81种物质，如琵琶湖。为了防止富营养化，规定了湖泊水库的氮磷统一排放标准，1985年7月，排放规定生效。随后，排放规定被扩展到更多湖泊水库。目前，氮磷排放规定分别在1200个湖泊和201个水库中生效。3.2 海洋和沿海地区措施1993年以来，为了防止海洋和沿海地区富营养化，氮磷排放规定在全国88个封闭盐水水域执行。此外，1998年4月，氮磷水污染环境质量标准在东京湾、依势湾和濑户内海执行，2000年3月在有明海执行。东京湾、依势湾和濑户内海也有了氮磷总污染承载控制标准。图 按年代顺序的日本水环境管理表格4 区域总污染负荷控制系统必须集中致力于有效地降低大封闭水体周围人口密集和工业化地区的污染物负荷来改善其水质。为了确保满足水污染环境质量标准，1978年对水污染控制法进行了修订以实施大封闭水体的区域总污染物负荷系统。区域总污染物负荷系统的目标地区为那些目前排放标准包括严格排放标准不足以达到和维持环境质量标准的地区。目标地区为东京湾、依势湾和濑户内海（图2）。此外，确定了各个指定水体（指定地区）内造成水污染的具体区域。每5年环境部对各指定地区都规定了COD污染物负荷减少目标和将满足这些目标的目标年份。根据总污染物负荷控制标准制订的规定构成了基于区域总污染物负荷减少系统的负荷降低措施的核心。总污染物负荷控制标准适用于每天污染排放量为50立方米或更多的特定商业设施。标准详细说明了每个商业设施的污染物排放的允许限度。COD是有机污染的一个主要指标。尽管区域总污染物负荷控制系统从1979年起已经执行了COD（图3），由氮磷汇入引发的富营养化也造成有机污染。因此，指定地区COD水平事实上仍旧没有改变，而赤潮再次成为问题。因此，2001年12月，第五次区域总污染物负荷控制系统（目标：2004财政年度）确立和一个区域总污染物负荷控制基本政策，将氮磷加入到先前的COD规定中（图1）。2002年7月，为了满足本政策中设定的负荷减少目标，受影响的地方政府创建了一个区域总污染物负荷减少计划。地方政府目前正在开展全面的行动以实现这些目标，包括建筑物的生活污水的对策和适用总污染负荷控制系统标准规定的工业排放物的对策，以及其他对策。图2 区域总污染物负荷控制系统下东京湾、依势湾和濑户内海的受影响地区图3 污染负荷趋势和减少目标参 考 文 献http:/www.env.go.jp/en/water/wq/pamph/index.html, “日本水环境管理”，日本政府环境部，2003An Outline of Water Environmental Managementin JapanKunio KOHATADirector, Water and Soil Environment DivisionNational Institute for Environmental Studies (NIES), Japan (Email:kohatanies.go.jp)Japans rapid economic growth during the 1960s was accompanied by water pollution of increasing severity and scope. This prompted the national government to take stronger measures to curb water pollution. The Water Pollution Control Law was enacted in 1970. Then, in the following year (1971), the Environment Agency was established, which took over the water environment policy in order to provide a centralized oversight for environmental conservation. Nevertheless, during the 1970s, environmental pollution became an increasingly serious issue around the Seto Inland Sea due to overpopulation and the growing concentration of industries. One of the consequences of this pollution was increasingly frequent red tides. The government responded with tougher measures to curb water pollution. In 1973, the Interim Law for Conservation of the Environment of the Seto Inland Sea was enacted, and in 1978, the law was made permanent and the term Interim was dropped. Furthermore, in 1978, a comprehensive and far-reaching series of laws was enacted to regulate the levels of pollutants in the Seto Inland Sea, Tokyo Bay, Ise Bay and other water bodies, wherein organic pollutants were a recurring issue. Then in 1984, the Law Concerning Special Measures for the Preservation of Lake Water Quality was enacted to combat the water pollution in freshwater bodies; however, to date, these measures have failed to yield results. Currently, the issues affecting the water environment are more serious than ever, and as mentioned above, the measures to combat them date back many years. In January 2001, the Environment Agency was reorganized as the Ministry of the Environment. This represents one more step in Japans long battle against water pollution.1 Environmental Quality StandardsThe Basic Environment Law establishes two kinds of EQSs (environmental quality standards) related to water pollution: EQSs for protecting human health and EQSs for protecting the living environment. Each type of standard establishes the levels desirable for achieving and maintaining the policy objectives for public water quality and other water quality. Uniform regulations for public water and groundwater have been enacted to achieve the first goal of protecting human health. In order to achieve the second goal of protecting the living environment, standards are set for each type of water body such as rivers, lakes and reservoirs, sea and coastal areas, and the like. Classification of public water bodies by type also helps in determining the environmental standards applicable to them. Currently, EQSs have been established for 26 substances related to human health, including cadmium and total cyanide. In March 1997, environmental standards for groundwater quality were established. EQSs related to the living environment, including standards for the BOD (biochemical oxygen demand), COD (chemical oxygen demand) and DO (dissolved oxygen), have been established. Furthermore, in order to prevent eutrophication, EQSs have been established for nitrogen and phosphorus levels in lakes/reservoirs and sea/coastal areas.2 Effluent Regulations The Water Pollution Control Law establishes the standards for effluents being discharged from factories and other commercial facilities that have facilities for discharging wastewater into public water bodies. These standards set specific concentrations for the various substances with regard to both human health and the living environment. As of year-end fiscal 2001, these regulations were applied to about 300,000 factories and other commercial facilities. Additionally, an Areawide Total Pollutant Load Control System has been adopted for enclosed water bodies (e.g. bays and inland seas); this system is described below. 3 Measures against Eutrophication3.1 Measures for Lakes and ReservoirsIn 1982, EQSs were promulgated for nitrogen and phosphorusthe two causes of eutrophicationwith the objective of countering eutrophication. The national and prefectural governments are studying the classes of substances to be regulated; as of fiscal 2000, they had identified a total of 81 substances in water bodies such as Lake Biwa. Fig. 1 A chronological diagram of water environmental management in Japan.Uniform effluent standards for nitrogen and phosphorus were defined for lakes and reservoirs in order to prevent eutrophication, and in July 1985, effluent regulations were brought into effect. Subsequently, the effluent regulations were expanded to cover more lakes and reservoirs. Presently, the effluent regulations for phosphorus and nitrogen are in effect for 1,200 and 201 lakes and reservoirs, respectively.3.2 Measures for Sea and Coastal AreasSince 1993, nitrogen and phosphorus effluent regulations were enforced for 88 enclosed saltwater bodies nationwide in order to prevent eutrophication in sea and coastal areas. Additionally, in April 1998, EQSs for water pollution related to nitrogen and phosphorus were enforced for Tokyo Bay, Ise Bay, and the Seto Inland Sea, and in March 2000 for the Ariake Sea. Total pollutant load controls for nitrogen and phosphorus are also in place for Tokyo Bay, Ise Bay, and the Seto Inland Sea . 4 Areawide Total Pollutant Load Control SystemFig. 2 Affected areas under the Areawide Total Pollutant Load Control System inTokyo Bay, Ise Bay and the Seto Inland Sea.Efforts must be focused on effectively reducing the pollutant loads in the populated and industrialized areas around large enclosed water bodies to improve their water quality. In order to ensure that the EQSs for water pollution were met, the Water Pollution Control Law was amended in 1978 to implement an Areawide Total Pollutant Load Control System for such large enclosed water bodies. The Areawide Total Pollutant Load Control System targets regions where the current effluent standards, including the stringent effluent standards, are insufficient for achieving and maintaining the EQSs. The targeted regions are Tokyo Bay, Ise Bay and the Seto Inland Sea (Fig. 2). Furthermore, specific regions contributing to water pollution are identified within each specified water body (specified areas). Every five years, the Minister of the Environment sets the COD pollutant load reduction targets for each specified area, and the target year by which they are to be met. Regulations in accordance with the total pollutant load control standards form the core of the load reduction measures based on the Areawide Total Pollutant Load Reduction System. The total pollutant load control standards apply to specific commercial facilities having effluent volumes of 50 m3/day or more. The standards specify the permissible limit for the pollutant discharge loads per commercial facility.The COD is a major indicator of organic contamination. Although the Areawide Total Pollutant Load Control System has been implemented for the COD since 1979 (Fig. 3), organic contamination is also caused by eutrophication, which is triggered by the influx of nitrogen and phosphorus. Thus, the levels of COD in the specified areas have remained virtually unc