Laserfiche WebLink
Metro Wastewater Reclamation District <br />The County also requested information <br />regarding the type of soils anticipated to be <br />encountered during pipeline construction. The <br />project is primarily along the South Platte River <br />corridor with soils consisting of fine or coarse <br />alluvium underlain by the Denver Formation. <br />The Denver Formation is generally <br />uncemented claystone and sandstone. <br />Groundwater is generally found above the <br />pipeline invert and will require dewatering prior <br />to trenching. Geotechnical Data Reports have <br />been provided to Adams County under <br />separate cover. <br />Hazardous materials studies were completed <br />along the pipeline alignments with sampling <br />and laboratory analysis conducted in select <br />areas. No evidence of hazardous materials has <br />been found to date along the pipeline corridor; <br />however, a plan for handling any materials <br />encountered during construction is included in <br />the bid documents. <br />An analysis has been completed to determine <br />the approximate available staging area at the <br />Debetz Pit site to facilitate the stockpiling of <br />spoils, reducing the staff commitment required <br />by Adams County to deposit the fill into the <br />site. The spoils staging area, shown in Figure <br />1, is assumed to be at the northeast corner of <br />the existing pit, and it is assumed that the <br />entirety of the 3 -acre site can be stockpiled to <br />an average height of two feet. The results of <br />this analysis indicate approximately 9,500 CY <br />of material can be stockpiled on -site prior to <br />requiring movement into the Pit to allow <br />additional spoils to be delivered. If the <br />stockpiled spoils are not removed to allow <br />additional spoils to be delivered, the SPI <br />contractor will dispose of the spoils in an <br />alternate location. It should be noted that a <br />portion of the 3 -acre site is within the South <br />Platte River floodplain and will require the <br />County to obtain a Floodplain Use Permit to <br />allow stockpiles to remain in place between its <br />activities to move the spoils into the Pit. <br />In order to ensure that spoils delivery can <br />occur at any time during construction, it is <br />recommended that only 50% (approximately <br />5,000 CY) of the staging capacity be filled prior <br />to Adams County placing the fill. This allows <br />for the Contractor to continue delivering spoils <br />SPI -14 <br />Table 1: Anticipated Spoils Quantities <br />Month <br />SPI Spoils <br />Minimum <br />(LCY /week) <br />Maximum <br />(LCY /week) <br />Cumulative <br />Average <br />Volume (LCY) <br />September -13 <br />320 <br />400 <br />1,918 <br />October -13 <br />150 <br />1,460 <br />4,213 <br />November -13 <br />1,420 <br />3,500 <br />14,314 <br />December -13 <br />1,720 <br />3,620 <br />27,246 <br />January-14 <br />1,070 <br />3,180 <br />34,338 <br />February -14 <br />640 <br />2,360 <br />40,251 <br />March -14 <br />1,290 <br />2,310 <br />49,312 <br />April -14 <br />1,110 <br />1,680 <br />54,753 <br />May -14 <br />620 <br />1,630 <br />59,199 <br />June -14 <br />470 <br />1,480 <br />63,809 <br />July -14 <br />0 <br />1,190 <br />65,538 <br />August -14 <br />0 <br />950 <br />67,550 <br />September -14 1 <br />0 <br />170 <br />67,752 <br />