Santa Cruz County Watchdog

There has been a lot of talk about how much water South32 has been approved to discharge at the Hermosa Project as part of its dewatering program required to access critical minerals. In fact, the US Forest Service has approved South32 to extract and discharge up to 6.5 million gallons of water per day at the Hermosa Project – that’s 20 acre feet of water per day for the life of the mine which may exceed 50 years.

That’s a lot of water, but it need not be treated as an afterthought. It can be strategically released in the mountains surrounding the Hermosa Project to recharge surface water aquifers that feed Harshaw and Sonoita Creeks and the Santa Cruz River via the San Rafael Valley. Here is a map showing some of the possible discharge locations around the mine:

The ‘blue’ lines represent stream channels, and the ‘orange’ lines represent ridge lines separating catchment basins. Please note that not all stream channels are marked on this map.

Discharging dewatering and treated water directly into washes and constructing low-tech and low-cost natural rock detention structures downstream of the discharge point has the following benefits –

• sequester atmospheric carbon in the soil
• maintain or increase vegetation and biomass
• extend ephemeral duration and surface-water availability
• mitigate floods and associated emergency response expenditures
• promote lateral flows and onsite storage of water
• control erosion and nonpoint source pollution
• improve water quality and reduce torpidity
• reduce ambient temperatures
• ensure access to water for wildlife all along stream channels

But, dewatering and treated water is not going to magically start flowing in these catchment basins on its own. It’s up to us to ensure that water is being discharged responsibly. South32 can only discharge water in the Coronado National Forest with US Forest Service permission, so it is critical that we let them know that we support this proposal. Please visit our Get Involved post and contact Local, State, and Federal governments, State and Federal Agencies and South32 to voice your support for discharging dewatering and treated water in the mountains around the mine.

So, you see, with some imagination, creativity, political will, and a desire to create a brighter future for the next generation of Arizonans, it is possible to turn lemons into lemonade.