1209 MADRONA AVE 2016-11-17 - Laserfiche WebLink

Geotechnical Engineering Evaluation Packer Proper[y Retaining u'alis and Steep Slope Evaluation Everett, u'ashington NGA File No. $70113 March 1 l, 2013 Page 9 connect v��ith the lou�est wall ar within a close proaimaty to that w•a1L We have provided recommendations far design and installation of a new pipe pile wall with timber lagging and tieback anchors to pratect the top of the siope and walls. The ancl�or system could consist af either �routed tiebacks �r mechanically installed anchors. We have also provided recommendations for some improvements on the slope to lessen the potential for future sliding. Detailed reconlmendations regarding the proposed wa11 have been included in the Reta�ning Walt Design and Construction subsectioz� of this report. The recent landslide izicludes the Packer praperty and the neighbor's property to the west. We strongly recoi��mend, if possible, that ihe two property ovvner's work to�ether an addressing the stability issues on tl�e two properties since these issues can direct]}� affect the proposed improvements if repairs are not performed on the neighboring western property as u�e1l. Additional similar sIope stability improvements such as e; osion cantrol and drainage systems would need to be conducted on the neighbor's property to help preti�ent future events impacting the new repairs on the Packer's property and to improve overall slope stability within the vicinity of the two properties. All construction c��erations and drainage improvements shouid be planned and completed in a manner tliat enhances the stability of the steep slopes, not reduces i#. Excavation spoils should not be stacicpiled near the top oC the slope, ar be left on the slope. Dependzng on canditions in the field during construction, the excavation spoils may be placed within the gentler ground at the bottom of the slope. This should be evaluated and approved by the geotechnical engineer. Water shauld not be allowed to concentrate or flow over the steep sIope. Future vegetation management on the slope shauld be the subject of a specific evaluation and a plan a�proved by the City of Eve�-ett. The slape should be monitored on an an-going basis, especially duri�� the u�et season, far any signs of instat�ility, and cor�•ective actians promptly taken should any signs of instabi�ity be observed. Lawn clipping and any ather debris should not be cast over the slope. The soits encounte�-ed on this site are considered highl5� moisture-sensitive and v��ill disturb easi2y when wet. To Iessen the potential impacts of construction an the slope and to reduce cost overruns and delays, we recammend that construction take place during the drier suzzuner months if possible. However, the repairs may have to be implemented sooner than that to reduce the potential for additionaJ slides. If construction takes place during tlae rainy months, additiona] ex�enses and delays should be expected. lVELS4?!V GEC)TECNl�IC�1L .�t SSf3ClATES, lNC.