Key Technical Issues with the Cargill Shaft #4 Project
1. Leakage water – Amounts:
Independent geologists have reviewed available documents relating to the mine and permit for Shaft #4 and are alarmed. There is a demonstrated risk of flooding Shaft #4 and the mine during drilling due to a hydraulic connection between an aquifer that would be drilled through and the Lake.
2. Leakage Water – Storage:
Cargill’s current plan is to store in the mine under the lake leakage waters collected both during the drilling Shaft #4 and once the shaft is in operation. However, in 2015, a Cargill consultant expressed concern that leakage waters from Cargill’s existing shafts are causing pillar erosion under the Town of Lansing, and that this poses a risk of mine collapse which could damage the existing shafts and the lake shoreline. We would add that any hydraulic connection between the lake and the mine poses the risk of salinizing lake water. Therefore, Cargill should not be allowed to store any additional water or brine in the mine.
3. Gas Handling:
The drilling of Shaft #4 will intersect several rock formations which commonly host natural gas in New York State. Cargill’s proposal of pulling the gases into the mine to then be vented to the atmosphere with mine exhaust is unacceptable. This complete lack of transparency regarding likely impacts to the climate, is intolerable and alone necessitates a positive declaration under SEQR for the Shaft #4 application.
4. Breach of DEC State Environmental Quality Review (SEQR) Process:
The drilling of Shaft # 4 and northward mining expansion are indisputably linked. Cargill has segmented these two pieces of the same project in breach of SEQR protocol. This breach should be reason enough to require a DEIS and public hearing. In such a hearing the DEC should correct Cargill’s improper application process by recombining Cargill’s improperly segmented permit application so that matters having to do with the mining of the tunnel as well as the mineshaft can be properly considered.
5. Depletion of Bedrock Groundwater Resources:
Groundwater leakage into Shaft #4 is likely to significantly aggravate the already widespread drainage and depletion of bedrock groundwater caused by inflows to the existing shafts over many decades of their operations. A measurement taken in Corehole 18 at the Shaft #4 location four miles miles from the existing shafts indicates that a potentiometric water level (the level to which water rises in a well) at the base of the Onondaga Formation has already been lowered by more than 100 ft. Cargill has failed to evaluate the existing and additional impacts from Shaft #4 on the bedrock groundwater resources in the region. No monitoring of such impacts has been proposed.