Lịch sử của ô nhiễm môi trường do các chất độc hại IS Tham gia và phức tạp. Mặc dù Một số Of Những chất trong môi trường tự nhiên có rất nhiều, rất nhiều là kết quả của công nghệ và con người manipu-lation các nguồn tài nguyên của trái đất. Một định nghĩa viết tắt cho các chất độc hại là "Bất kỳ, rắn, lỏng, hoặc khí nào là độc hại, dễ cháy, ăn da, phản ứng / nổ, và / hoặc phóng xạ." Hôm nay của sản phẩm công nghệ May Be Bất kỳ một hoặc kết. | Chapter 2 An Historic Overview Introduction The history of environmental contamination by hazardous substances is involved and complex. Although some of these substances abound naturally in the environment many are the result of technology and human manipulation of the earth s resources. An abbreviated definition for hazardous substances is any solid liquid or gas which is toxic flammable caustic reactive explosive and or radioactive. Today s technological products may be any one or a combination of these and greater than 80 of all industrial chemicals can be classified as hazardous. Past reports have given press to aquatic graveyards resulting in a usage ban for those who would avail themselves of the water for fishing drinking or recreation. Rivers lakes and streams have been contaminated with industrial waste. Fish populations have been destroyed or rendered inedible and communities have reported noxious odors emanating from local surface waters. Many of these sites are in the process of being remedied or have already been cleaned. Groundwater has shown signs of hazardous chemical migration through the soils both horizontally and vertically. Many of these occurrences develop as a result of contaminants in the soil for twenty years or more. Soil and surface water contamination past and present are an ever-present threat to potable drinking water. Hazardous materials have been quietly discharged through industrial effluent dumping into sanitary sewers industrial automotive air emissions and ground soil contamination through mismanagement of hazardous wastes. Many of the discharges can and have been corrected. Yet ongoing activities and contamination continue to be the result of carelessness and criminal activities. The . government response has been to identify locations for remediation and prevent further incidents from occurring. Identification of these locations requires investigation . environmental site assessments and prevention comes in the form of .
