500. UNIT FOUR ENVIRONMENTAL HEALTH AND SAFETY Hazardous Waste Management Handling hazardous waste in the United States has become a big business(see Figure 15.9). There are several approaches to managing hazardous waste. During the 1980s, about 89% of the hazardous waste in the united states was placed in the earth by way of land disposal (57%)or discharged into sewers, rivers, or streams secured landfll(22%). The remaining 11% was processed for recycling(4%), burned in industrial a double ined landfil boilers(4%), chemically treated(1%), land treated(for biodegradable waste)(1%) In ond away Ioi or incinerated(1%). ' While there is now legislation in place that regulates the dis- a fault zone posal of all hazardous wastes, illegal dumping still occurs monitoring pipes for Secured Landfill The least expensive and perhaps least environmentally sound means of disposing primany Tor hazordous waste of hazardous waste is placing it in a secured landfill. Such a landfill differs from a sanitary landfill in its location, design, and ability to be monitored. Some of the requirements for secured landfills are that they must be: (1) located above the 100- year flood plain and away from fault zones, (2) double-lined with clay or a synthetic urface water material, and (3)equipped with pipes that enable them to be monitored for any rafer found on the seepage. The owner must provide for area wells for the monitoring of groundwater, eorth's surfoce, as well as monitor the surrounding surface water (water on the earth's surface ambles oceans rivers, streams There are several drawbacks of the use of secured landfills for the discarding of hazardous waste. Some authorities feel that even the best-built secured landfill will eventually leak because the clay liners will crack or the synthetic liners will break FIGURE 15.9 The management of hazardous wastes is becoming big business