Tri-Service Remedial Project Manager's Guide for Ecological Risk ...

(&2/2*,&$/5,6.$66(660(17²7+(%$6,&6This section describes the different phases of the ERA and introduces many of theterms and components necessary to manage an ERA. For a more detailed description, pleaserefer to Section 4. (5$$*HQHUDO2YHUYLHZAn ERA is generally performed during the RI phase of a CERCLA/SARA project orduring the RFI phase of a RCRA project, although it may be initiated earlier. Most ERAs aredivided into a screening level (Tier 1) ERA and a baseline (Tier 2) ERA (Figure 1). A screeninglevel ERA is a simplified risk assessment that can be conducted with limited data and usesconservative assumptions to minimize the chances of concluding that there is no risk when infact a risk exists. In a baseline ERA, the conservative assumptions are eliminated and replacedwith best estimates to more accurately assess the site’s risk. When an ERA is conductedearlier than the RI or RFI phase, it is a screening level ERA.Regardless of whether a screening or baseline ERA is being conducted, the followingprocess is always followed: Planning, Problem Formulation, Analysis, Risk Characterization,and Risk Management (Figure 2). During both Planning and Risk Management, it is vital tohave discussions between both the risk assessor (the person responsible for conducting theERA) and the risk manager (the person responsible for the installation’s restoration project as awhole; generally this is the RPM or his/her supervisor) because they both bring importantperspectives to the table. During Problem Formulation, Analysis and Risk Characterization, therisk manager (RPM) will be less involved in day to day decisions, but still should remain awareof what is going on.3ODQQLQJPlanning involves the determination of the level of effort necessary for the ERA. This isaccomplished during discussions among the RPM, risk assessor, risk manager, stakeholders,regulators, and others involved in the decision process. Every attempt should be made incoming to an agreement on the following issues before proceeding into the risk assessment.l Establish management goals (i.e., the plant, animal, or ecosystem we are trying toprotect).l Agree on the scope, complexity, and focus of the ERA. Include expectedoutput/results and what technical and financial support will be needed.l Agree upon methods to be used during the ERA. These methods must bescientifically defensible and should determine if management goals are met.l Establish times in the ERA where major decisions will be made and how thesedecisions will be made. Key decisions should be documented in writing for futurereference.7