Why The Risk to Wells Is So High

Listen to a talk given by Gary Pierazzi, a local resident, during the MineWatch/CEA Foundation December Community Event. Full transcript follows.




Welcome, and thanks for being here tonight.


As a resident whose sole source of water is my well, I'm really concerned about the impacts the Mine could have. There are a large number of private wells in the Idaho-Maryland Mine mineral rights area and hundreds more in the surrounding area. Residents are very concerned that if their wells fail, run dry, or become contaminated, they'll have to find another way to get water. Rise Gold has claimed that other than a small number of wells, the project won't have any significant impact on resident’s wells... … water supply, but here's the thing. They can't promise that because groundwater hydrology is uncertain, and they could only provide predictions and assumptions.


So tonight, I'll talk about the following issues related to residential wells, which will include residential well locations, dewatering, well mitigation measures, hydrological studies, impacts to residential wells, and what is needed to protect the wells.


So let's start with well locations. This map shows the mineral rights boundary for the Idaho-Maryland Mine. It's designated in this black dotted dashed line. And that's the boundary. According to the California Department of Water Resources, there are over 300 domestic wells within a thousand feet of the Idaho-Maryland Mine mineral rights boundary. The Department of Water Resources online database identifies over 1200 private, domestic wells that are located within one to two miles of the project.


Rise Gold believes that there are only 26 wells that can be impacted by dewatering of the Mine. Those wells are located along East Bennett Road shown on this map here outlined in the large blue rectangle in the center of the map. The map also shows the Upper Wolf Creek Watershed in pink and the South Fork Wolf Creek Watershed in green. Moving on to dewatering.


For this mining project, Rise Gold will need to dewater the existing mine workings. Their groundwater analysis report includes the following information. “Before exploration and mining can proceed, the volume of water contained in existing workings must be removed from the underground workings. Removal of the static water within the flooded mine workings is referred to as initial dewatering. Once the initial dewatering is completed, continued pumping is necessary to remove groundwater that will constantly flow into the Mine through fractures within the bedrock. For the purposes of this report. it will be referred to as maintenance dewatering.”


This little chart shows that there's two parts: the initial dewatering, and maintenance dewatering. And the pumping rate in the initial dewatering is 2,500 gallons per minute. And that will be 24 hours a day, 7 days a week, for six months. Bringing the total to 3.6 million gallons being pumped per day, or 657 million gallons within a six-month period of the initial dewatering. Then, they move on to the maintenance dewatering, which is 850 to 1,500 gallons per minute. And there's a range there, because during the rainy season the pumping rate would be higher due to the groundwater inflows. That also will be 24 hours a day 7 days a week, but this will be for the duration of the project. So the gallons pumped during the maintenance dewatering would be roughly one to two million gallons per day or roughly 450 to 750 million gallons per year.


With that amount of water being constantly pumped out of the ground, 24/7, for the life of the project, well owners should be very concerned. I know I am.


Let's look at mitigation measures. Rise Gold believes that there are only a few wells that could be impacted by the dewatering of the Mine. Those are the few wells along East Bennett that I mentioned previously… that we're in the blue rectangle.


Here's Rise’s mitigation measures for impacted wells… from the Rise ground water and hydrology report. It reads as follows: “A buried potable water pipeline will be added to provide water to residents along a portion of East Bennett Road. The existing NID potable water pipeline will be extended on East Bennett Road to provide potable water service to residents currently on wells that may be affected by the project.” And from their land use technical study, it states... “In approving Mine projects which according to expert opinion, may threaten the existing quality or quantity of surface or subsurface water - which supply adjacent homes and businesses - the County shall require the operator to guarantee a comparable supply of water to such homes or businesses through accessible forms of security, or alternative sources of water.” What does that mean? What is a comparable supply of water? They don't say. What is an accessible form of security? I don't know what that means. It's very vague and they don't give us any more information that would clarify. And, what are the alternative sources of water? They don't say. Is it water brought in by trucks? Is it a large tank installed on your property? Will they be delivering water to your home for the life of the project? We don't know what these alternative sources are, or how they'll be delivered.


Those few sentences are the basis of protection for all our wells. This isn't a serious mitigation plan.


The report goes on to say, “Areas near the Mine not currently served by NID and NID's potable water supply system are: East Bennett area, Beaver Drive area, Greenhorn area, Woodrose area”. And all these areas surround the Mine. This means there is no NID water service to hook up to those areas if your well goes dry… with the exception of the proposed East Bennett NID pipeline. And with no NID service, you’re out of luck if your well is impacted.


Let's move on to well impacts. So here's a few possible impacts that could happen as a result of the dewatering and mine activity. Reduced well water output (reducing gallons per minute). Reduced well recharging rate. Contamination of well water. Complete well failure (your well actually going dry). No reliable source of water. Inability to live in your house with no reliable source of water. And loss of investment through devaluing properties without a reliable source of water.


After reading those potential impacts, it's unbelievable that this project would ever be approved without NID service first being made available.


Rise Gold believes that out of hundreds of wells in the area, only 26 that I previously mentioned would be impacted by dewatering. What's that based on? Rise Gold mitigations are based on their hydrology reports. Because they can't see underground and know exactly what's there, and how waterflows will behave, the hydrologists make hydrogeological studies. The hydrogeologic studies create models and uses assumptions to predict where the water will go when the mine workings are dewatered So: They make models. Then they make assumptions based on the models. Then they make predictions…based on the assumptions… based on the models.


In the end, there's no certainty in these hydrological studies… only assumptions. I want to read this from the Todd report, which was a hydrogeological study done in 2007. when the Idaho-Maryland Mine Corporation was applying to get a permit for the Mine. It reads: “Even with assumptions, predictions, and models, it is not possible to know with certainty how the geological system will respond to dewatering, whose hydrogeology is difficult to predict. Monitoring of domestic wells should be maintained outside the potential area of impact that span both the Wolf Creek and South Fork of Wolf Creek watershed. They would be used to monitor the potential expansion of the cone of depression caused by the Mine dewatering and ensure additional areas outside the area of potential impact are monitored. This would account for potential inaccuracies in analysis, especially along known fault zones. It would also allow analysis to determine if dewatering of one watershed, affects an adjacent watershed.”


Also regarding inaccuracies in prediction from another hydrogeologic study I want to read this: From the 1993 final report for groundwater modeling and proposed underground mining at San Juan Ridge, which is just up the hill, and one that the County approved. The report stated: “Water levels in water supply wells surrounding the site are predicted to undergo very little or no impact from mine dewatering.” In reality, their predictions were dead wrong. In 1995, there was a breach of an aquifer at the Mine causing millions of gallons of water. Mine waste discharge spilled into Spring and Shady Creeks. The breach also drained community wells including those of Grizzly Hill School and North Columbia Schoolhouse Cultural Center. And in 1997, the San Juan Ridge Mine was closed.


You can see impacts are unpredictable, and this leaves all wells in our vicinity vulnerable to impacts from dewatering and mining.