realistically and reasonably made and if they are 

 needed to describe irreversible or irretrievable com- 

 mitnnents of resources or the relationship of short- 

 term uses of man's environment to long-term pro- 

 ductivity, as required by NEPA and the CEQ NEPA 

 regulations (40 CFR 1502.16). 



(g) A without-plans condition should be ex- 

 pressed for several specified future dates, herein 

 after called forecast dates. A sufficient number / 

 forecast dates should be selected to permit ade- 

 quate description of future changes in the indicator. 

 However, the number of forecast dates should not 

 be so large that an unreasonable information 

 burden is created. A proper balance between ade- 

 quate description and information demands should 

 be achieved. Without-plans conditions should not 

 be expressed as an average or median over the 

 period of analysis if such expressions would ob- 

 scure future changes in an indicator. 



(h) A without-plans condition should be the most 

 probable future condition for an indicator. 



(i) Appendix A provides an example documenta- 

 tion format for recording the results of this activity. 



3.4.8 Forecast with-plan conditions activity. 



(a) This activity is performed to develop informa- 

 tion that measures or otherwise describes the 

 future conditions of EQ resource attributes under 

 each of the alternative plans being considered. 

 With-plan conditions should be estimated for each 

 alternative plan in terms of the same quantity and 

 quality indicators used in the previous activity. 



(b) The bases for estimating with-plan conditions 

 include those used in forecasting without-plans 

 conditions: Trend and existing conditions, related 

 forecasts, institutional objectives and constraints, 

 effects of other actions, the effects of natural oc- 

 currences, and the known effects of comparable 

 past actions (see 3.4.7(c)). 



(c) Approaches that should be considered for 

 forecasting with-plan conditions include those used 

 in forecasting without-plans conditions: adoption, 

 scenario writing, expert judgment techniques, ex- 

 trapolation techniques, and analogy and compara- 

 tive analyses. (See 3.4.7 (d) and (e)). 



(d) The subsection on information collection pro- 

 grams (3.4.6(c)) and forecasting without-plans con- 

 ditions over the entire period of analysis (3.4.7(f)) 

 are also applicable to with-plan conditions. With- 

 plan conditions should be estimated for the same 

 forecast dates used for the without-plan conditions 

 (see 3.4.7(g)). 



(e) Appendix A provides an example documenta- 

 tion format for recording the results of this activity. 



3.4.9 Assess effects phase. 



This phase is performed to identify and describe 

 effects of alternative plans on EQ resource attri- 

 butes. In the first activity, without-plans conditions 

 and with-plan conditions are compared to identify 

 differences between them. In the second activity, 

 identified differences (effects) are described in 

 terms cf duration, location, and magnitude. In the 

 third activity, the significance of these effects is de- 

 termined. 



3.4.10 IdcTitify effects activity. 



(a) This activity is performed to identify differ- 

 ences between the without-plans and with-plan es- 

 timates for each indicator. An effect is shown to 

 occur whenever without-plans and with-plan esti- 

 mates of an indicator are different at one or more 

 of the forecast dates. 



(b) If all of the specified indicators for a particular 

 EQ attribute of a resource are shown to be unaf- 

 fected by each of the alternative plans (that is, 

 each indicator's without-plans and with-plan esti- 

 mates are the same for all forecast dates), the un- 

 affected attribute should be eliminated from EQ 

 evaluation. The attribute should be reintroduced 

 into EQ evaluation if it is likely to be affected by a 

 new alternative plan. 



(c) Appendix A provides an example documenta- 

 tion format for recording the results of this activity. 



3.4.11 Describe effects activity. 



(a) This activity is performed to describe each 

 effect identified in the previous activity. Effects 

 should be described in terms of their duration, loca- 

 tion, and magnitude. 



(b) Duration is the time at which, or over which, 

 an effect is expected to occur. It should be de- 

 scribed for the forecast dates and may be summa- 

 rized in terms of a time period beginning at a spe- 

 cific time, such as "20 years beginning in 1990." 

 Duration will usually be confined to a span of time 

 within the period of analysis, but some effects, such 

 as the loss of a distinctive land-form, may exceed 

 the period of analysis (see 3.4.7(f) and 3.4.7(d)). 



(c) Location is the place at which an effect is ex- 

 pected to occur. It should be described in terms of 

 an identifiable geographic location, such as "be- 

 tween river miles 57 and 63." The location of an 

 effect should be described as specifically as possi- 

 ble without revealing the location of sensitive re- 

 sources such as archaeological sites and endan- 



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