1110 RAINIER AVE A DOMESTIC VIOLENCE SERVICES OF SNO CO 2018-01-01 MF Import

� Evere(t Nausirg Authoriry May 16, 2012 � JN 12080 Page 3 just above lhe existing grade. Where overexcavations for the building foundations are expected to be approximately fi feet or less, using conventional (ootings for ihe buildings that lhat are placed on the competent native soil or on structural fill placed over the competent native soil would be a standard foundation option. However, where deeper overexcavations would be needed to reach competent soil, avoiding the overexcavalion and using a deep foundation system is likely a more economical system. Because the buildings are not tall and there is little slope at the site, we believe that using driven pipe piies is a very feasible and economical foundation system for this project; additionat informalion regarding the piles is given in a subsequent section of this report. Peat soil was revealed in ihe test borings in approximately the area of the proposed eastern building and the eastern end of the southwestern building. This soil is highly organic and thus is very compressible. Based on the condition of the lo�ver parking lot, it appears that settlement of the peal soil has been occurring since fill soit was placed over it to construcl the parking lot. Seltlement of the peat wi�l likely continue in the future; this would thus negalively affect any fioor slabs constructed for these buildings. For this reason, unless the peat is removed, the pipe piles should also be used to support slabs of these buildings. IF a crawl space syslem is used, lhen ihe piles �vould just be neec�d for foundations. Projects involving small-diameter pipe pites often include the need for lateral resistance from fill placed against the foundations. If this is the case for ihis project, it is important thal the structural engineer indicale this requirement on lhe plans for the general and earthwork contractor's information. Because of the existence of the peat soil on this site, it is likely that some settlement cf the ground surrounding piie-supported buildings will occur over time. In order to reduce the potent�al problems associated with this, we recommend lhe following: Fill to the desired site grades several months prior to constructing on-grace slabs, walkways, and pavements around the buiidings. This allows the underlying soils to undergo some consolidation under the new soil loads before final grading is accomplished. Connect all in-ground utilities benealh the iloor slabs to the pile-supported floors or grade beams. This is intended to prevent utilities, such as sewers, from being pulled out of the floor as the underiying soils settle away from the siab. Hangers or straps can be poured into the floors and grade beams to carry the piping. The spacing of these supporting elements will depend on the distance that the pipe material can span unsupported. Construct all entrance walkways as reinforced slabs thal are doweled inlo the grade beam al the door thresholds. This will allow the walkways to ramp down and away from Ihe building as they settle, wilhout causing a downset at ihe threshold. • Isolate on-grade elements, such as walkways or pavemenis, from pile-supported foundations and columns to allow differential movement. The drainage andlor walerproofing recommendations presented in this report are inteoded only to prevent active seepage From ilowing through concrete walls or slabs. Even in the absence of active seepago into 2nd beneath slructures, waler vapor can migrate through walls, slabs, and floors (rorn the surrounding soil, and can even be lransmitted from slabs and foundation walls due to the concrete curing process. Water vapor also resulls from occupant uses, such as cooking and GEOTECH CONSULT�NTS, INC.