Contaminated Runoff. 3.7.3 If the asbestos roofing is removed, the interior of the building can be exposed to rainfall. Contaminated runoff may be generated from the precipitation in contact with the contaminated equipment, floor slab, soil and debris. The runoff may cause off-building migration of contaminants and this will have surface and groundwater impact. Detailed proposal of the mitigation measure is given in Section 5.
Contaminated Runoff. 5.2.3 There are environmental mitigation measures to minimize the contaminated runoff. The registered asbestos contractor and site engineers shall be briefed of the precautions and responsibility to prevent contaminated run-off and the asbestos abatement work will be avoided during rain events. Technically, temporary roofing will be provided for the building with the asbestos roofing removed. The temporary roofing shall have the following features; • Temporary solid roofing, such as plastic panels should be provided to withstand against heavy wind or rain; • The temporary roofing should be in a slant orientation to prevent accumulation of rainwater; • Joints/ overlaps of the roofing panels should be sealed and duct-taped to ensure water- tightness; • The roofing panels should be securely tied up to the existing roof frame and regularly maintained of their integrity.
Contaminated Runoff. Various sites contribute to the contamination of runoff into the Port. Discharge from these sites is continuous or intermittent during warm weather but essentially ceases in winter when the ground is covered with snow. Runoff from residential, commercial, and industrial sites can carry oils and fuels, metals, and a variety of other chemicals into the Port. Sites where runoff can become contaminated include various large and small-scale petroleum-related industries, storage and fueling facilities, high density residential and commercial areas within the city, municipal and construction waste landfills, the airport, residential sub-divisions where septic tanks are used, active and inactive mines, and roads and highways. The Xxxxxx Small Boat Harbor on the north shore of the Port receives much of the stormwater from the city and from the harbor grounds where boats are repaired and stored on land. Old Valdez and areas to the north and east are zoned for industrial use (City of Xxxxxx, 1992). The airport, which uses de-icing chemicals, is located in this area and a municipal and construction waste landfill operate north of the Valdez Glacier Stream. There was an old landfill in Old Valdez that was closed and covered in the early 80s. Leachates from the landfills are possible, especially when ground water levels are high. The deposition of air contaminants also increases the potential for surface water contamination. In Xxxxxx, air pollution occurs on a local scale through industrial emissions, fuel and wood burning for home heating, and vehicle and vessel emissions. Industrial emissions include volatilization of hydrocarbons during crude oil loading at the Xxxxxx Marine Terminal and during treatment processes at the BWTP (Xxxxx, 1992; Xxxxxxxxx et al., 1992). Hydrocarbons which enter the atmosphere as vapors are rapidly dispersed and photo-oxidized; however, hydrocarbons (especially PAH’s) which are adsorbed onto soot particles eventually settle back onto land or water. Regionally, forest fires can release particulates and gases, including PAH’s, on an irregular basis. Aerial transport of PAHs and metals over long distances has been shown to contribute to marine pollution (Xxxxxxx and Xxxxxxxx, 1991; Xxxxx et al., 1980). Pesticide use is probably low, except for insecticides applied by the city and private companies to kill mosquitos and black flies in the summer. In June and July of 1994 the City applied 6 gallons of Multicide in approximately 33 hours of spra...
