Laserfiche WebLink
TRAUTN E R ~ <br />A DIVISION OF 7RIGON~~'13 <br />Mr. Brian Kimmel <br />Southwest Land Service <br />November 29, 2006 <br />~rs......d ~ ~.J <br />f EB 16 2007 <br />842'h Main Avenue Division of Reclamation, <br />Durango, Colorado 81301 Mining and Safety <br />PN 50663GE <br />Subject: Durango Commercial Development Airport Business Park Access Roadway <br />Geotechnical Engineering Clarifications <br />Durango, Colorado <br />Mr. Kimmel, <br />This letter is in response to our November 289, 2006 meting with Mr. Matt Carnahan, Mr. Rob <br />Harries, P.E., Goff Engineering, Mr. Ralph Wegner, Four Corner Materials and Mr. Patrick Breagy, <br />Yenter Companies regarding the subject project. Our geotechnical engineering report for this <br />roadway was submitted on November 20, 2006 <br />On Page 20 of the report we refer to the maximum recommended steepness of the post <br />construction slopes as 2'ha, horizontal to vertical unless a stability analysis is performed. Since the <br />stability analysis, was performed this comment is not appropriate. The proposed cross sections, as <br />shown on the plans prepared by Goff Engineering were analyzed as shown in the report, therefore <br />the 2:1 horizontal to vertical slopes aze appropriate for our analysis of the proposed roadway. <br />The report recommends that 12 inches of existing subgrade be scarified, moisture conditioned and <br />compacted. Mr. Wegner indicated that this depth of scarification and compaction will require <br />removal of about 6 inches of material followed by processing and compaction prior to replacement <br />of the overlying 6 inches to achieve the 12 inch thick prepazed subgrade. Mr. Wegner indicated that <br />they could process a maximum of 8 inches of subgrade soil in place without removal of material. <br />We typically recommend scarification, moisture conditioning and compaction of the subgrade <br />materials so that the field conditions are similaz to those analyzed in our laboratory testing program. <br />The minimum of 8 inches of scarification, moisture conditioning and compaction of the subgrade <br />soils should be considered as appropriate to realize the values and recommendations presented ir_ <br />our report. <br />Please contact us if you have any questions, or if we may be of additional service. <br />Respectfully, <br />TRAU E6~H _~ <br />j ~ _ <br />Da ~ i_, ^ ~r, P..E., CPG <br />1~ . <br />Cc: Mr..Rob Harries, P.E., Goff Engineering <br />Mr. Ralph Wegner, Four Comers Materials <br /> <br />G EDTECHNICAL ENGINEERING, MATERIAL TESTING AND ENGINEERING GEOLOGY <br />214 BODD DRIVE DU RANGD, COLORADO 81303 97D-259-5095 97D-3B2-2515 FAX <br />