Comments on Proposed Nash Road Quarry Reclamation Plan
Mine ID# 91-35-0015
Sierra Club Loma Prieta Chapter
April 25, 2024
The following are initial comments on the Proposed Nash Road Quarry Reclamation Plan (Plan). We ask the appropriate party to address these items in the Draft Reclamation Plan. Thank you for your sincere consideration of these comments.
General Comments on Proposed Reclamation Plan
- The Reclamation Plan should include a schedule with milestones and detailed specifications for interim reclamation. Areas that will not be affected by mining (all Reclamation Areas except B and E) should be reclaimed as early as possible during Phase 1 mining. We believe more active reclamation is necessary in these areas since no reclamation has been performed to date to restore damage from previous mining.
- As proposed, habitat restoration through natural recruitment is insufficient. Some active habitat restoration will be needed given the extent of disturbance on the property, particularly within the riparian corridor. In the absence of mining one can only presume the habitat on this stretch of the river could support the diversity of species found surrounding the property. It is mining and the lack of reclamation that contributes to the lackluster habitat recorded in the biological surveys. Therefore, the Reclamation Plan should include additional measures to revegetate reclamation areas to provide habitat for endemic species. Special attention should be given to the use of native plants since that is a best practice.
- Monitoring of erosion in the river channel should extend beyond 2,000 feet upstream and 2,000 feet downstream of the mining area (Plan, pg. 21). The erosional effects of instream gravel mining can be manifested miles upstream and downstream from the site of operations.
- The Reclamation Plan should be more specific about monitoring and reporting requirements, and how the information is used for adaptive management, as follows.
- Mining below the thalweg increases the risk of upstream and downstream degradation and therefore should occur in a very cautious manner, allowing only small increases in depth every year (for example, .5 foot per year).
- Triggers for adaptive management are either lowering of thalweg upstream and downstream, or scour at adjacent bridges (Plan, pg. 23). Please explain how the required monitoring measures scour and changes in thalweg. A thalweg and scour survey using benchmarks should be conducted every year before any decision to recommence mining.
- Please explain what information provided by plan-form mapping will be used to adaptively manage mining operations.
- The Reclamation Plan needs to specify monitoring to ensure that reclamation is successful, including metrics of success such as extent of revegetation, and additional actions to be taken if measures fail to meet specified metrics.
- Monitoring should be conducted by an independent third party (paid for by the applicant).
- Adaptive management (Plan, pg. 22) should be improved as follows.
- Monitoring and adaptive management is needed during Phase 1 because Phase 1 is the bulk of the mining which will occur. Degradation can occur due to any instream mining and needs to be addressed if it occurs.
- Mining should cease if degradation occurs, whether it is caused by mining or not. At least there should be specific requirements to show whether mining caused any problems (e.g. independent report by expert hydrogeologist hired by the County and paid for by the applicant).
- The Reclamation Plan needs to specify what happens if adverse impacts are found. Will mining be allowed to recommence once certain actions are taken and certain conditions are reached? Or will the quarry close and be reclaimed?
- Reclamation soil coverage requirements seem insufficient as follows.
- Under Reclamation Plan Content Checklist, the Plan says “No compaction planned for any end use” (Plan, pg. 142). However, the Checklist also says requirements for urban (residential) use include that “fill shall be compacted in accordance with Uniform Building Code, local grading ordinance, or other methods approved by the lead agency” (Plan, pg. 142) and “Areas to be developed for ... residential shall be revegetated for the interim period” (Plan, pg. 149). Reclamation measures for Reclamation Area E need to be updated to meet these requirements.
- The Checklist says “non-prime agricultural land must be reclaimed to be capable of sustaining economically viable crops common to the area” (Plan, pg. 151). Specific reclamation requirements to sustain crops need to be analyzed and documented in the Reclamation Plan to ensure proper reclamation of Reclamation Area D for agricultural uses.
Requests for Additional Information in Reclamation Plan
- The Reclamation Plan should clarify the width of the flow channel at each phase of the mining process. Is it the entire riverbed or a narrower subset of the riverbed?
- More information is needed about the materials to be stockpiled and the process for utilizing or disposing of these materials (Plan, pg. 70).
- What is the content of the materials and how will the materials be used?
- Will mining waste be stockpiled?
- What happens to the removed material at the end of each mining year? Will the material be disposed of off-site and if so, where?
- More information is needed about the operation of the settling pond as follows.
- Provide information about pond capacity and estimated inflow.
- Address how silt that builds up in settling ponds is managed and how water is disposed of once materials have settled.
- Include analysis to show that the pond is self-sealing (Plan, pg. 13).