|
Amy Eschberger Reference No. 20144265-REV1
<br /> Colorado Division of Reclamation,Mining and Safety September 4,2020
<br /> 4.0 REPORTING
<br /> 4.1 Field Documentation
<br /> Following the field program and installation for MW-8, a technical memorandum summarizing the well installation
<br /> will be prepared and submitted to the DRMS within 60 days of well installation and development. The
<br /> memorandum will include discussion of the field activities performed and subsurface conditions encountered or
<br /> inferred. The borehole geologic logs, well installation/construction logs, and water level measurements will be
<br /> presented as tables or attachments. The well installation logs will include coordinates, elevations, well installation
<br /> date, well material type, well depth, screened interval, filter pack interval, bentonite seal interval, and the
<br /> interpreted screened unit. The geologic logs will include depths, elevations, descriptions of subsurface materials
<br /> (soil and rock) encountered, and depths to groundwater. Finally, monitoring well permit applications will be filed
<br /> with the Colorado DWR.
<br /> 4.2 Data Evaluation and Reporting
<br /> Monitoring results from MW-8 and MW-9 (if installed)will be presented in the semi-annual monitoring reports.
<br /> Once sufficient data exist to be able to evaluate the MW-8 results by the methods described in Section 3, a field
<br /> investigation summary will be prepared that present this evaluation. The field investigation summary will include
<br /> an evaluation of the water quality data obtained at MW-8, a comparison of this data to water quality observed at
<br /> other site wells screened at similar depths and lithology(MW-4, MW-6, and MW-7), and a discussion of whether
<br /> data obtained from MW-8 indicates that concentrations of any of the parameters evaluated can be interpreted as
<br /> representing natural groundwater conditions and not CKD-impacted groundwater. This evaluation will be
<br /> conducted for barium, boron, chloride, fluoride, gross alpha, iron, manganese, nitrate as N, nitrate + nitrite as N,
<br /> selenium, sulfate, TDS, and uranium.
<br /> If, after concentrations stabilize, a demonstration can be made that the concentrations observed in MW-4, MW-6
<br /> and MW-7 are reflective of background conditions (i.e., similar to MW-8), the field investigation summary will be
<br /> submitted as a Technical Revision to the permit. In this case, the Technical Revision will specify that MW-9 will
<br /> not be necessary and request that MW-6 or MW-7 be classified as the point of compliance.
<br /> If a demonstration cannot be made that the concentrations observed in MW-4, MW-6 and MW-7 are reflective of
<br /> background conditions, the field investigation summary will specify a timeline for installation of MW-9 as a point of
<br /> compliance well. In this case, the field investigation summary will not be submitted as a Technical Revision
<br /> because MW-9 will be installed in accordance with this Technical Revision. If MW-9 is installed and a
<br /> demonstration can be made that the concentrations observed in MW-9 are below the BSGW or reflective of
<br /> background (i.e., similar to MW-8), a Technical Revision to the permit will be issued to evaluate whether existing
<br /> and reasonably potential future uses of groundwater are protected (on the basis that BSGW or background water
<br /> quality is not being exceeded)and, if so, request the discontinuation of the groundwater monitoring program.
<br /> REFERENCES
<br /> Golder, 2010, Groundwater Sampling and Analysis Plan for the Boettcher Limestone Quarry in La Porte,
<br /> Colorado. Golder Associates Inc., Lakewood, Colorado, April 28, 2010.
<br /> Golder, 2018. Request for Technical Revision of Permit M-1977-348: Changes to the Groundwater Analyte list at
<br /> The Boettcher Quarry Golder Associates Inc., Lakewood, Colorado, September 5, 2018.
<br /> GOLDER 6
<br />
|