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COLORADO LEGACY LAND <br /> Topsoil Borrow Area: <br /> On Thursday November 10, 2022 Ensero Solutions US, Inc. supported by their construction subcontractor, <br /> Kessler Reclamation, dug eight test-pits at two areas within the permit boundary. Five test pits (Sample ID: <br /> Test Pit#1,Test Pit#2,Test Pit#3,Test Pit#4,and Test Pit#5) were dug across Ralston Creek in the former <br /> lay-down area and three test pits (Test Pit#6,Test Pit#7,and Test Pit#8)were dug near the toe of the Mesa. <br /> Figure 6 shows the location of each test pit. The topsoil borrow area across the creek is approximately 0.54 <br /> acres and the test pits in this area extend to approximately 8 feet deep,yielding approximately 6,969 cubic <br /> yards of borrow material. The topsoil borrow area at the toe of the Mesa is approximately 1.87 acres and the <br /> test pits in this area extends to approximately 12 feet deep, yielding approximately 36,203 cubic yards of <br /> borrow material. Soil samples were collected from each test pit for grain size,Atterberg limits,moisture,and <br /> organic content by Ensero Solutions US,Inc.and sent to Energy Laboratories Inc.for analysis on November 10, <br /> 2022. Preliminary analytical sample results (all results except for Atterberg limits) are presented in <br /> Attachment D. The full analytical results are expected back in late-December 2023 and shall be shared with <br /> DRMS when available. <br /> This test pitting exercise coincided with DRMS'fourth quarter inspection of the site. The primary objective of <br /> the test pitting work was to identify an onsite borrow source for topsoil (up to 5,727 cubic yards). In AM-06, <br /> CLL committed to importing topsoil for reclamation if required. These analytical results indicate good sand <br /> content(58%-82%) which classifies these soils as a loamy sand or a sandy loam,and organic matter suitable <br /> for plant growth (1.5%to 3.5%)exists in these soils,and higher organic content(2.5%to 3.5%) in the soils in <br /> the area at the toe of the Mesa. Soils with higher clay content require higher organic content to be good for <br /> plant growth media,but for soils with a sandy loam or loamy sand classification,a range of 2%to 3%organic <br /> matter is considered adequate. Further,for all of these samples,the organic matter content is at least 10% of <br /> the clay content,which is a threshold that is considered important for soils to be classified as"good quality"for <br /> use as a plant growth medium because of the effect this ratio has on soil structure <br /> (hhUps://bsssjournals.onlinelibrary.wiley.com/doi/10.1111/eiss,l3012). Although a typical plant growth <br /> media specification for organic matter varies,particularly in the rocky mountain region,evidence of current <br /> onsite growth suggest that these soils will support growth. As described in Attachment C,CLL is committed to <br /> establishing vegetative cover during reclamation and will achieve the vegetative cover required. <br /> Cut-off Wall,Bypass Pipeline.and Associated infrastructure: <br /> On December 5, 2022 CLL submitted a renewal application for their USACE permit(Corps File# NOW-2011- <br /> 01353-DEN). In this application CLL requested to keep the following infrastructure in place: the cut-off <br /> wall/bridge,as well as the associated rip-rap in Ralston Creek,and the bypass pipeline.The bridge above the <br /> cut-off wall provides good site access along Glencoe Valley road. The bypass pipeline would remain in place <br /> but would be buried for aesthetic reasons. This pipeline provides the site owner and other project stakeholders <br /> a systematic redundancy for when CLL transitions surface water flows back to Ralston Creek at the completion <br /> of the alluvial valley reclamation work and could have other unknown uses in the future. The riprap armoring <br /> in Ralston Creek would also remain in place as this provides stability to the channel during high-flow <br /> conditions. If preparation of this renewal application CLL communicated the contents of the renewal <br /> application to USACE,who provided preliminary approval of these changes to the permit. <br /> Water Treatment Plant Demolition: <br /> On November 28,2022 CLL communicated with Jefferson County's building permit department and established <br /> a path forward for confirming that the existing Water Treatment Plant on the Mesa meets the county building <br /> codes. Due to COVID-19 staffing delays and shortages this process is expected to take a few months'time. Final <br /> documentation from Jefferson County,showing that the structure is consistent with county building codes,shall <br /> be shared with DRMS when available. <br /> In-Situ Treatment: <br /> In AM-06 CLL describes adding phosphoric acid on an as-needed basis as a nutrient for microbes. However, <br /> subsequent to this amendment, CLL has compared the in situ treatment effectiveness for times when this <br /> phosphoric acid was included in the in situ treatment amendment with times it was not utilized and does not <br /> see a correlation between the reduction in uranium or other constituents with when it was or was not used. <br /> This indicates that the mine wall rock and/or the biofilms already grown in the mine pool contains sufficient <br /> PAGE 3 OF 23 <br />