902 PINE ST NORTH SOUND BEHAVIORAL HEALTH TREATMENT CENTER 2025-11-04

GeoTest Services, Inc. November 16,2018 North Puget Sound Behavioral Health—Treatment Center Addition Job No. 18-0770 the other. For this reason,we recommend that the owner and design team participate in the I selection of a pavement section for the site. Site grading plans should include provisions for sloping of the subgrade soils in proposed pavement areas, so that passive drainage of the pavement section(s) can proceed uninterrupted during the life of the project. We anticipate that asphalt pavement will be used for new access drives and parking areas. It is assumed that any existing unsuitable fill and organic soils will have been removed I prior to paving activities and that pavement subgrades will consist of firm and unyielding native till, existing fill or properly placed and compacted structural fill overlying firm and unyielding native material or existing fill. We recommend that all areas intended to be paved be proof rolled with heavy machinery prior to the placement of structural fill. Due to the potential moisture sensitivity of the existing native and fill soils, compaction during wet grade or wet weather conditions is not recommended. Overexcavation of subgrade soils or reinforcement of subgrades with geotextile fabrics may be warranted during wet conditions. GTS should be allowed to review a grading plan prior to the start of construction as the I amount of on-site grading has the potential to influence the pavement subgrade recommendations that we have presented below. Light-duty Flexible Pavement Sections We recommend a minimum, pavement section consist of 2.5 inches of Class 1/2-inch HMA 1 asphalt above 2 inches of WSDOT Standard Specification 9-03.9[3] Crushed Surfacing Top Course(CSTC), overlying 4 inches of crushed surfacing base course(CSBC)meeting criteria of the WSDOT Standard Specification 9-03.9[3]. Asphalt, CSTC and CSBC sections should be founded on firm and unyielding native till, existing fill or on properly placed and compacted structural fill overlying firm and unyielding native deposits or existing fill. If overexcavation is not feasible in areas that are found to be deflecting, pumping or yielding, we recommend using a woven geotextile fabric such as TenCate® Mirafi®RS 280i or industry equivalent overlying the existing native or fill soils. Heavy-duty Flexible Pavement Sections We recommend a minimum, pavement section consist of 4.0 inches of Class 1/2-inch HMA asphalt above 4 inches of WSDOT Standard Specification 9-03.9[3] Crushed Surfacing Top Course(CSTC), overlying 4 inches of crushed surfacing base course(CSBC)meeting criteria of the WSDOT Standard Specification 9-03.9[3]. Asphalt, CSTC and CSBC sections should be founded on firm and unyielding native till, existing fill or on properly I placed and compacted structural fill overlying firm and unyielding native deposits or existing fill. If overexcavation is not feasible in areas that are found to be deflecting, pumping or yielding, we recommend using a woven geotextile fabric such as TenCate® 111 Mirafi®RS 280i or industry equivalent overlying the existing fill soils. Concrete Sidewalks and Hardscapes I We anticipate that Portland cement concrete (PCC) will be used for walkways and hardscapes. We recommend a concrete sidewalk and hardscape section consisting of 4 inches of PCC surfacing above a minimum of 4 inches of CSTC. It is assumed that sidewalks and hardscape sections will be placed over a firm and unyielding subgrade as previously addressed herein. Page 14 of 17 i