2600 FEDERAL AVE KIMBERLY CLARK Geotech Report 2022-10-25

' May 25, 2017 HWA Project No. 2015-104-21 6 feet thick. A 3.5-foot gap was measured between structures. However, after the explorations were completed, we received structural drawings of the boiler house foundations (Sheet EB60, dated 1929) from Bryan Lust, which showed that the distance between foundations for the same ' tank saddle were approximately 14 feet, so the foundations we encountered were probably adjacent structures. Using GPS location data from the exploration, we believe we located the eastern foundation of Boiler #2 and the western foundation of Boiler #3. The bottoms of the foundations extended beyond 7 feet below current ground surface (Concrete rubble was 3.6 feet thick in this area). ' Wood Stave Storm Water Pipe ' On 4/15, Bryan took us to the pier on the western edge of the site, where an access hatch near the bulkhead showed the general outfall area of the storm pipe. He also pointed out a manhole on the edge of the pier that lined up with the outfall pipe and could be used to orient the exploration near the bulkhead. Excavations were oriented north -south to cut across the orientation of the pipe. In our first excavation, the top of the pipe was located at 5.6 feet below the surface (Pipe #1). We moved to a second excavation area (Pipe #2) 150 feet to the east, using the manhole, ' access hatch, and located pipe as a guide. Bryan mentioned that the pipe alignment changes direction somewhere in the vicinity of the current haul road running through the site. However, ' without accurate measurements, misrepresentation of the true location of the bend could put the second leg of pipe across a wide area of the site. A "best guess" was made and the second trench was excavated. Stem walls and a flat slab were located at 3 and 6 feet, respectively. The second ' excavation totaled 28 feet in length to a maximum depth of 7 feet. The pipe was not located. A third excavation was started (Pipe #3), 50 feet to the east of the first excavation, and for a length of 35 feet. Again, the wood stave pipe was not located during the excavation, however multiple ' stem walls and slab floors were encountered. On 4/16, after importing the GPS data taken in the field on 4/15 into QGIS, we assumed that we had not excavated far enough to the north. With this information, we re -excavated the northern end of the third trench, and moved to the north (Pipe #4). Total excavation to the north was approximately 20 feet, to a depth of 7 feet. Again, stem walls and slabs were observed, but no stave pipe was located. ood Piles Area - Near the southwestern corner of the site, the annotated drawings showed an area where wood pilings remain buried in place. We used GPS coordinates to locate the extent of the drawn area in the field. Excavation was started at the "center" of the drawn area, and the trench was extended toward the south. Total excavation length was 39 feet. Concrete rubble was not ' spread in this area during the recent demolition work, but fill was still observed that contained brick, reinforcing steel, and concrete fragments. Three stem walls (2- to 4-feet wide) and a slab were encountered during the excavation. The excavator operator attempted to dig underneath ' the slab to find any pilings, but was Technical Memorandum 3 HWA GeoSciences Inc.