Agenda - Council - 09/25/1990 - Laserfiche WebLink

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I I I I I I I i I I i I I I i I I I and analysis completed since that time has the potential to alter this figure. The most recent data should be utilized. o A Response Action Plan (RAP) dated February 1990 is referenced. It was not clear what the current status of this plan is regarding MPCA approval or the anticipated schedule of implementation. The affecLof_the RAP on the groundwaLer .._ flow was also not addressed. Section C: Regional Geology No comments. Section D: Regional Hydrogeology On p. P-95 it states that "results of the area well search for Site P indicates that the St. Lawrence-Franconia (CSLF/CFRN) bedrock formation is the predominant aquifer used based on the results of the well inventory. This aquifer is utilized by about 64% of the wells inventoried." The second sentence is not entirely accurate. The aquifer is utilized by about 64% of the wells for which depth data was available is truly correct. Because of this distinction, statements like the first sentence must also be interpreted accordingly. It is very important that the reader bear in mind that the aquifer usage percentage stated in the document are based on the total number of wells within the study area. The distinction is especially important in this case because only a relatively low number of wells out of the total wells had depth information available (234/718 - 35%: Table P.D.1). As an example, assume that the wells with unknown depths are all completed in the buried outwash. Then, the percentage of wells in the CSLF/CFRN bedrock formation would be 152/718 = 21% rather than 152/235 = 64%. While this example is extreme and not very reasonable, it was merely to illustrate that since well depth 3