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HomeMy WebLinkAbout03289 CD ... - ' d) L' - 1 v. .. " tl % cri O iJ � ,S - 7 , 3 i / f ° • O , `CD _ ' • A PD y ` • i. 1 ■ .. , LI I - - -.. /, Co — [� I I ''i s ql . J tr- 1 -----'-i m 3. ` 00 I r. Sz.rol (D x 14 .4 . 4 , -'/ ^ qo 1 s I : ..-- r- IF, p0 CuwtotE�a o > n > 1 1 ... ., \. . r• y o ' 1 M I II 1 1 / 'JL�C c �, 1 Feb -24 -00 031.44P town #of #debebeque 970+283+5205 P.02 • t; moisture requirements; irrigated grass should not be located within 6 feet of the foundation. Sprinklers should not discharge within 6 feet of the foundation and should be directed away from the building. Irrigation should be limited to the minimum amount sufficient to maintain vegetation; the application of additional water will increase the likelihood of slab and foundation movements. 6. Impervious plastic membranes should not be used to cover the ground surface immediately surrounding the residence. These membranes tend to trap moisture and prevent normal evaporation from occurring. Geotextlle fabrics can be used to control weed growth and allow some evaporation to occur. PERCOLATION TESTING We excavated three percolation pits (P -1 through P4) and one profile pit (Profile) in the area of the planned percolation field in the approximate locations shown on Figure 1. Graphic logs of the subsoils exposed in the pits are shown on Figure 2. Percolation tests were performed in excavations made into the bottom of the test pits. Results of our percolation tests are shown on Figures 4 through 6. Percolation test results Indicate that a design percolation rate will be out 20 minutes per inch. We recommend the percolation field be designed by an engineer qualified in septic field design such as Church and Associates, (3113) 463 317 LIMITATIONS Our exploratory pits were spaced to obtain a reasonably accurate picture of Subsurface conditions. Variations in the subsurface conditions not Indicated by our pits will occur. We should observe the completed foundation excavation to confirm the soils are as anticipated from our exploratory pits and suitable for support of the designed footings. Our report was based on conditions disclosed by our exploratory pits, engineering analysis and our experience. Criteria presented reflect our understanding of the proposed construction. We should be advised if the final OAKWOOD HOMES LOT 16, KLOCK 6, ELK CREEK 6VSOIWSION OM OS-1894 8 F_ -24 -00 03!44P town#of#debeboque 9704-2834-5205 P.03 • , 0 8 & § » 0 K K 0 J CO k ( � \¢ \ . . w / k= �@ a 2 — e . .. w 2a )\ F w §\i § rui m O E rig ■F ; « k 0 .. §4,-2 2 § 4 § I- \ • TABLE OF CONTENTS SCOPE 1 SUMMARY OF CONCLUSIONS 1 SITE CONDITIONS 2 PROPOSED CONSTRUCTION 2 SUBSURFACE CONDITIONS 2 SITE EXCAVATION AND GRADING 3 FOUNDATION 4 SLAB -ON -GRADE CONSTRUCTION 6 BELOW -GRADE CONSTRUCTION 6 SURFACE DRAINAGE 7 PERCOLATION TESTING 8 LIMITATIONS 8 FIGURE 1 - APPROXIMATE LOCATIONS OF EXPLORATORY PITS FIGURE 2 - SUMMARY LOGS OF EXPLORATORY PITS FIGURE 3 - EXTERIOR FOUNDATION WALL DRAIN FIGURES 4 THROUGH 6 - PERCOLATION TEST RESULTS TABLE I - SUMMARY OF LABORATORY TEST RESULTS OAKWOOD HOMES LOT 16, BLOCK 5, ELK CREEK SUBDIVISION CTL/T GS -2894 SCOPE This report presents the results of our soils and foundation investigation for the proposed residence on Lot 16, Block 5, Elk Creek Subdivision in New Castle, Colorado. We conducted the investigation to evaluate the subsurface conditions at the site and provide foundation recommendations for the proposed single family residence. Our report was prepared from data developed during our field exploration, laboratory testing, engineering analysis and our experience with similar conditions. This report includes a description of the subsurface conditions found in our exploratory pits, our opinions and recommendations for design criteria for recommended foundation and floor systems, and geotechnical and construction criteria for details influenced by the subsoils. The recommendations contained in the report were developed based on our understanding of the planned construction. Revisions to the anticipated construction could affect our recommendations. A summary of our conclusions is presented below. SUMMARY OF CONCLUSIONS 1. Subsurface conditions found in our exploratory pits consisted of 4 inches of silty clay "topsoil" and 2 feet of silty clay underlain by weathered to comparatively unweathered claystone bedrock to the total explored depth of 9 feet below existing ground surface. Free ground water was not found in our exploratory pits during excavation operations. 2. We recommend constructing the residence on footing foundations. Design and construction criteria for footings are presented in the report. 3. The proposed residence will be modular building with a structural floor system. Slab -on -grade construction will be limited to exterior flatwork at this site. We judge potential differential movement of slabs -on- grade supported by the subsoils at this site will be low. 4. Surface drainage should be designed to provide for rapid removal of surface water away from the proposed residence. OAKWOOD HOMES LOT 16, BLOCK 5, ELK CREEK SUBDIVISION CTLJT GS-2894 • construction. Experience indicates over a period of time, moist conditions can develop in crawl spaces which result in damp, musty smells and standing water. To reduce the risk of accumulation of water in crawl spaces, we recommend provision of a foundation drain. The drain should consist of a 4 -inch diameter, open joint or slotted pipe encased in free draining gravel. The drain should lead to a positive gravity outlet, or to a sump pit where water can be removed by pumping. Gravity outlets should not be susceptible to clogging or freezing. A typical foundation drain detail is presented on Figure 3. The crawl space should be well ventilated. SURFACE DRAINAGE Surface drainage is critical to the performance of foundations and concrete flatwork. We recommend the following precautions be observed during construction and maintained at all times after the residence is completed: 1. Wetting or drying of the open foundation excavation should be avoided. 2. The ground surface surrounding the exterior of the residence should be sloped to drain away from the residence in all directions. We recommend providing a slope of at least 12 inches in the first 10 feet around the residence, where possible. In no case should the slope be less than 6 inches in the first 5 feet. We recommend incorporating a drainage swale above the residence to direct surface water around the residence. 3. Backfill around the exterior of foundation walls should be moistened and compacted to at least 95 percent of maximum standard Proctor (ASTM D 698) dry density. 4. Roof downspouts and drains should discharge well beyond the limits of all backfill. Splash blocks and downspout extensions should be provided at all discharge points. We specifically recommend against burying downspout discharge pipes because it increases the potential for subsurface wetting near the foundation. Snow should not be allowed to accumulate adjacent to the residence. 5. Landscaping should be carefully designed to minimize irrigation. Plants used near foundation walls should be limited to those with low OAKWOOD HOMES LOT 16. BLOCK 5, ELK CREEK SUBDIVISION 7 CTL1T GS.2894 • ' SATURATION AND PREPARATION PERCOLATION TEST DATE: 11/01/99 DATE: 11/024/99 TIME AT START OF SATURATION: 4:43pm WATER IN BORING AFTER 24 HOURS YES X NO PERCOLATION TEST RESULTS DEPTH TO WATER HOLE DEPTH TIME AT TIME CHANGE PERCOLA- NUMBER (INCHES) START OF INTERVAL IN WATER TION RATE INTERVAL (MINUTES) START OF END OF DEPTH (MIN /INCH) INTERVAL INTERVAL (INCHES) (INCHES) (INCHES) P -2 47 1:31 10 0.0 3.0 3.0 3 1:41 10 3.0 4.75 1.75 6 1:51 10 4.75 5.75 1.0 10 2:01 10 5.75 7.0 1.25 8 2:11 10 7.0 8.0 1.0 10 2:21 10 8.0 9.0 1.0 10 2:39' 10 • 0.0 2.5 2.5 4 2:49 10 2.5 3.5 1.0 10 2:59 10 3.5 4.5 1.0 10 3:09 10 4.5 5.5 1.0 10 3:19 10 5.5 6.5 1.0 10 3:29 10 6.5 7.5 1.0 10 3:39 10 7.5 8.0 0.5 20 3:51* 10 0.0 1.5 1.5 7 4:01 10 1.5 3.0 1.5 7 4:11 10 3.0 4.5 1.5 7 4:21 10 4.5 6.0 1.5 7 4:31 10 6.0 7.0 1.0 10 4:41 10 7.0 7.75 0.75 13 Hole refilled with water 1 1 i Q Job No. GS -2894 Fig. 5