4626 HARBOR LN 2018-01-02 MF Import

Gcotechnical Engineering Evaluation Fox Residence Underpinning and Retaining Wall Design Everett, Washington NGA File No.853512 August 3, 2012 Page 11 'File level spreader should be installed perpendicular to the tightlined pipe, and should consist of a 20-foot long trench, two feet deep, and one -foot wide. A 4-inch rigid perforated pipe should be installed at the bottom of the trench. The trench should be filled with washed rock and covered with filter fabric. A woodet water -treated board should he placed on the downhill side of the trench to help water spread out evenly. The approximate location of the pipes, catch basin, and level spreader are shown on Figure 8. This is approximate and the actual locations can be determined in the field during construction. CONSTRUCTION MONITORING We should be retained to provide construction monitoring services during site grading and block wall construction, to evaluate subgmde conditions, cut conditions, fill compaction, wall installation, and drainage installation. USE OF THIS REPORT NGA has prepared this report for Mr. Logan Fox and his agents for use in the planning and design of the development planned on this site only. The scope of our work does not include services related to construction safety precautions and our recommendations are not intended to direct the contractors' methods, techniques, sequences, or procedures, except as specilically described in our report for consideration in design. 'there are possible variations in subsurface conditions between the explorations and also with little. Our report, conclusions, and interpretations should not be construed as a warranty of subsurface conditions. A contingency for unanticipated conditions should be included in the budget and schedule. We recommend that NGA be retained to provide monitoring and consultation services during construction to confirm that the conditions encountered are consistent with those indicated by the explorations, to provide recommendations for design changes should the conditions revealed during the work differ from those anticipated, and to evaluate whether or not earthwork and foundation installation activities comply with contract plans and specifications. We should be contacted a minimum of one week prior to constnrction activities and could attend pre -construction meetings if requested. Within the limitations of scope, schedule, and budget, our services have been perforated in accordance with generally accepted geotechnictl engineering practices in effect in this area at the time this report was NELSON GEOTECHNICAL ASSOCIATES, INC.