API PUBL 4709-2001 pdf free download

API PUBL 4709-2001 pdf free download.Risk-Based Methodologies for Evaluating Petroleum Hydrocarbon Impacts at Oil and Natural Gas E&P Sites.
Risk-based decision-making is the process of making environmental management decisions based upon an assessment of the potential risks that chemicals at a site may pose to human health and the environment. The Environmental Protection Agency of the United States (U.S. EPA) has developed a general framework for health risk-based decision mak- ing and has established general guidelines for determining what constitutes acceptable risk. These guidelines can be used to determine when some type of action is required at a site. The general framework for risk-based decision making was originally developed by the U.S. EPA, largely in response to the requirements of the Comprehensive Environmental Response and Contingency Liability Act of 1980 (CERCLA). A major goal of this framework is to make certain that management decisions for environmentally impacted sites provide an adequate level of protection for human health and the environment. As part of this framework, a health risk evaluation process was developed and the overall risk characterization is used to guide site management decisions. The risk evaluation process, as originally set out by USEPA, involves four elements: ? Hazard identification ? Exposure assessment ? Toxicity (or dose-response) assessment ? Risk characterization It is complete, comprehensive, and can be used to evaluate health risks at all types of contaminated sites. Although the process was developed for use at sites impacted by hazardous materials, in reality it is equally applicable to all types of sites, including oil and gas industry E&P sites.
However, since none of these goals is directly tied to the actual risks posed by the chemicals of concern, there is no way to determine whether or not these goals actually protect human health and the environment. T RADITIONAL A PPROACHES M AY M ISALLOCATE R ESOURCES There is no way to determine the cost/benefit associated with achieving the management goals listed above, since the benefit of the action cannot be determined. Without any knowledge of the benefit resulting from a given action, there is no way to prioritize actions to focus them on those problems where the greatest potential for risk reduction exists. This could conceivably result in a portion of the public being left at risk, and in the misallocation of both the technical and financial resources of this country. This represents a problem because there is a limit to the resources that the United States has available to solve the environmental problems in the oil and gas, or any other, industry. R ISK -B ASED A PPROACHES P ERMIT C OST -B ENEFIT A NALYSES In contrast, risk-based approaches to site management clearly describe the potential health benefits that might result from a particular environmental management decision. Consequently, the actions that are taken at a site can be evaluated and prioritized based on the actual reduction in risk that would be achieved and technical and financial resources can be allocated appropriately. S HOULD I T B E U SED A T A LL S ITES ? Like all technical methodologies and protocols, risk-based decision- making is not necessarily applicable to every situation at every E&P site. For example, there may be instances where a risk-based assess- ment concludes that TPH concentrations at a specific site do not pose a health risk. However, these same concentrations may produce unsight- ly conditions that may influence site management decisions.
One drawback of the risk-based decision-making process, as originally developed by U.S. EPA, is that it can require a substantial investment of technical and financial resources, as well as time. Also, the data required to complete the risk evaluation are often not readily available. For these reasons, tiered strategies tailored for specific types of sites have recently been developed by regulatory agencies and by indepen- dent organizations to permit its cost-effective use. One example of this type of effort is that developed by the American Society for Testing and Materials (ASTM).