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| Volcanic tuff pozzolan exposed at Kirkland Mine |
Return of Arizona Mining Review
Following a 15-month hiatus, the Arizona Mining Review (AMR)
filmed and its 40th episode, Pozzolan mining in central Arizona, on
28 Aug 2017. The Arizona Geological Survey’s Geologic Extension Service launched
the Review in Jan. 2013. With a few lapses, we released monthly episodes until
May of 2016. In May, the Review went on hiatus as we moved from State Agency
status to the College of Science at the University of Arizona. Plans to restart
the program in Aug. 2016 were put on hold after host Lee Allison’s tragic death.
We are now back in business and ready to explore and
broadcast developments in Arizona’s mining and mineral industry.
Developing a Pozzolan Mine in central Arizona with Areta Zouvas and Al Burch (Kirkland Mining
Co.) (https://www.youtube.com/watch?v=NrWV2c5YPGw)
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| Project map for pozzolan at Kirkland Mine. |
The small mine in the low hills north of Kirkland encroaching
on the southern edge of Skull Valley, Yavapai County, Arizona, has been worked
on-and-off for more than 100 years. It’s seen half-a-dozen name changes to
reflect changes in use of its mining products. In the 1950s, it was the Arizona
Capital Mine, as cutters carved out dimension stone for the Arizona State Capital
building. In the 1970s, it was the Kitty Litter Mine, as a more prosaic product
was harvested.
Currently, Kirkland Mining Co. president Areta Zouvas and
project manager Al Burch are working with the Bureau of Land Management (BLM)
to re-permit the quarry to mine pozzolan. (The Zouvas family has owned the
Kirkland Mine claims since 1989.) An environmental assessment of the mine and
environs, a requirement of the BLM, is underway and expected to take 12- to 18-months
to complete. If approved, the quarry could open shortly thereafter.
Pozzolan is a geologic
material – a volcanic tuff or ash – that when admixed with water, lime, sand
and gravel makes a superior and long-lived concrete. Pozzolan is named for the
town of Pozzuoli in Italy. Two thousand years ago, the Romans mined pozzolan
near Pozzuoli to enhance concrete of new buildings and pillars, some of which
still stand today.
Kirkland’s pozzolan deposit is hosted in Miocene-age
volcanic tuff. The tuff is a white to tan, massive crystal-lithic tuff in
excess of 250 feet thick that dips gently to the northeast. Extraction of the
tuff requires simple earth-moving equipment to quarry and crush the stone. The
mine operators anticipate extracting ~500,000 tons of ore annually at peak
production at an astounding 95% rate of yield for as much as 40 years.
The resulting pozzolan mine will find a market in the western U.S., where it likely will be processed and sold as a Supplementary Cementitous Material (SCM) added to cement and concrete to replace or be blended with Fly Ash to enhance the durability and strength of concrete.
The resulting pozzolan mine will find a market in the western U.S., where it likely will be processed and sold as a Supplementary Cementitous Material (SCM) added to cement and concrete to replace or be blended with Fly Ash to enhance the durability and strength of concrete.
Online Resources
- ‘BLM invites comments on ‘pozzolan’ mine in Skull Valley, Central Arizona’ Arizona Geology Blog post.
- BLM Resources – FAQs, Documents: Mine Process & Anticipated Equipment; Draft Mining and Reclamation Plan of Operations; Conceptual Mine Plan; Biological Evaluation, and more. How to get involved: Public scoping period.
- Kirkland High Quality Pozzolan Mine – Fact Sheet, Project Timeline & FAQs
M. Conway
