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Wattenberg Mine, Exhibit G—Water Information May 2023 Holcim's Wattenberg Lakes facility complies with applicable requirements in the Colorado Discharge Permit System (CDPS) General Permit COG500000 for Sand &, Gravel Mining Wastewater& Storm Water combined. The Colorado Department of Health and Environment (CDPHE) Water Quality Control Division (WQCD) considers stormwater runoff combined with mine dewatering water to be process water. The available monitoring well data will be used to observe changes in alluvial groundwater flow associated with mining and reclamation activities. Baseline data collected from the monitoring program will provide a range of water levels for comparison with groundwater levels during site activities under this permit amendment. These data will be utilized to evaluate the nature and extent of the change to the prevailing hydrologic balance and, if necessary, provide for the development of corrective actions. Well owners in the section below refer specifically to owners of wells from which extracted water is put to beneficial use, such as water wells, irrigation wells, etc. Owners of monitoring wells are not considered well owners in this context since a change in water levels for these wells does not represent material damage in cases where water extraction is not being conducted. In the event of a well owner complaint, Holcim commits to reporting any complaints received from well owners to the DRMS within 48 hours, investigating the complaint as soon as practical, and submitting the results to the DRMS for evaluation within 30 days. For the investigation, the first level of response will be to review water level data from the monitoring well network and, if available, a measurement of the water level in the well of those making the complaint. Information will be evaluated to determine if the complaint may be tied to dewatering or the slurry walls. If the data indicates that there is no reason to believe the well of those making the complaint was impacted by dewatering or the slurry walls, that will conclude the action taken by Holcim. If the data does not clearly show there is no impact, as a second level of response Holcim will present a contract to the well owner requesting access to the well to perform mechanical and electrical inspection and testing of the well and associated system, e.g., the pressure tank. The agreement will explain that if the problem with the well is not due to a lower water level and is instead due to a mechanical or electrical issue, the well owner will be responsible for the repairs. If the well is determined to be in good working order and the problem is due to a lower water level, then the mining-associated impacts will be addressed to the satisfaction of the DRMS. If the DRMS determines that the impact on a well for which temporary mitigation has been initiated is not a result of Holcim's activities or is not solely a result of Holcim's activities, Holcim will reduce or cease mitigation accordingly. In the event of a complaint that a well has become unusable, and based on the inspection results described above, Holcim will implement mitigation measures within 7 days. Mitigation measures would include providing a temporary alternative water supply that meets the documented historic well production or need until further investigation can be conducted to determine if the well condition is due to the mining activities. The DRMS, and potentially the Mine Land Reclamation Board (MLRB), are responsible for determining if mitigation is required, as well as when and how any mitigation measures are implemented and discontinued after the initial complaint is received. Should DRMS or MLRB conclude that mitigation action is required, Holcim will begin to implement one or more mitigation measures. Temporary mitigation measures may include, but are not limited to: • Compensation for well owners to use their existing treated water system to replace the well production loss. • Provision of a water tank and delivery water as necessary to meet documented historic well production or need. • Other means acceptable to both the well owner and Holcim. Long-term mitigation measures may include, but are not limited to: • Cleaning a well to improve efficiency. • Providing an alternative source of water or purchasing additional water to support historic well use with respect to water quantity and quality. If needed, water quality parameters will be checked in affected wells to ensure alternative sources support the historic use. OTETRA TECH Page 7 1 8