Laserfiche WebLink
f. Representative cross sectional diagram Please provide a representative cross-sectional <br />diagram of a typical monitoring well installation. Please note that piezometcrs may be adeyuatc <br />for measurement of groundwater monitoring levels. <br />g. Length of Monitoring l'he applicant has proposed monitoring groundwater elevations for a <br />period of I? months following completion oC the slurry wall installation. If after 12 or more <br />months of monitoring the applicant believes there is sutlicient data to demonstrate that <br />groundwater monitoring is no longer needed at the site, the applicant may submit a request to the <br />Division to discontinue the groundwater-monitoring program. The Division will review such <br />request and dctemtine i f the rcyuest may be granted. <br />3. The applicant has specified that the velocity and volume o(tlows expected on sift from a iOU- <br />year floxf event, as well as the elevation of the f 00-year bate flood event and its relation to the <br />elevation of the spillways and lakcshore berm is provided in the Conditional Letter of Map <br />Revision (C'LOMRI previously provided. Please clarify where in the CLOMR this information is <br />located, or provido i f not previously submitted. Also, plcasc quantify or characterize the <br />expected groundwater surface behvicen the stream channel and the adjacent floudplain to the <br />north undersuch an event. <br />4. The applicant has proposed installation of three (3) spillways along the riverside of the <br />reclaimed pond embankment(s) during final reclamation. Please specify wherein the CLOMR <br />document the Division may find the criteria used to determine the number of spilhvays to install <br />in the reclaimed lake(s) and the spacing between spillwavs. Since the reclaintcd lake and slurry <br />wall installatiom will be adjacent to a reach of the St. Vrain River that is over 1 mile in length, the <br />applicant will need to verify the number of spillways needed and the spacing interval needed to <br />ensure that floodwaters from a 1 tH)-year flood event will be discharged back safely to the main <br />channel of the SL Vrain River within a reasonable period of time and also maintain the stntctural <br />integrity of the slurry wall installation as well as the surrounding area. Please respond. <br />5. Please commit to providing an "As Built" certification from a registered, professional engineer <br />or other qualified person within Gll days ofcomplction of the embankment stabilization project <br />that the embankment stabilization has been completed according to the approved designs so as to <br />provide adequate protection against abank-full stream flow event or front floodwaters resulting <br />from a 100-year flood event, whichever is greater. Also, the applicant will need to comnnl to <br />providing revised maps and engineering designs for any significant changes required due to <br />unforeseen field conditions. plcasc responJ. <br />6. The applicant hat specified two (2) distinct scenarios fire the height of riverside embankment <br />to receive nprap installation, and these scenarios arc haled on the proximity of the St. Vrain <br />River to the existing ponds. Please clarify the criteria that the applicant well use to differentiate <br />when each trcatmcnt will be applied, and plcasc commit to providing riprap armoring or other <br />slope protection measures for any riverhank location that is not currently stable from either <br />vegetation or existing riprap or corn rete installation. <br />