PHOENIX, Ariz. - The Arizona Department of Environmental Quality issued permits on Sept. 1 to Denison Mines (USA) Corp. for parts of three proposed uranium mines in Northern Arizona that will protect groundwater and air quality in the Grand Canyon National Park region, including visibility in the Canyon.
Among the permits issued to Denison are an air quality permit for the proposed Arizona 1 Mine, north of the Grand Canyon, which is the last permit the company needs before beginning operations. Aquifer protection permits are also issued for Denison's proposed Pinenut Mine, north of the Grand Canyon, and Canyon Mine, south of the Grand Canyon. Additional permits for air and water quality are expected to be required for both the Pinenut and Canyon mines.
The air quality permit for Arizona 1 Mine, after extensive analysis, requires safeguards to ensure that mine operations -- including hauling uranium ore 37 miles on dirt roads to Arizona Highway 389 and mine vent and emergency generator emissions -- will not result in reduced visibility at the Grand Canyon, and to ensure that mine operations do not violate any of the National Ambient Air Quality Standards (NAAQS) established by the U.S. Environmental Protection Agency.
In particular, Denison will use tracking devices to monitor truck speed to ensure that haul trucks do not exceed 25 mph to reduce particulates. The haul routes were included as part of the ambient air quality modeling which demonstrated that no violation of NAAQS would occur from mine operations.
The aquifer protection permits require the continuous removal and monitoring of the volume and quality of water from underground mining operations. The results of the monitoring for contaminants conducted by an independent laboratory will be sent to ADEQ quarterly in the first year of operation and annually each year thereafter. ADEQ maintains the right to inspect the mines at any time and to take ADEQ's own samples for laboratory testing from the underground mine water at any time.
The aquifer protection permits also require protections against groundwater infiltration to ensure that Denison and ADEQ are made aware of any conditions that could result in migration of pollutants toward groundwater. The permits require rock and soil permeability testing at the bottom of the shafts and sumps, along with necessaryprotections to prevent the migration of pollutants.
The permits also require financial assurance funding be posted with ADEQ by Denison to assure there are funds to close, and test the environment at, the surface impoundments after mine closure. Additional financial assurance will be required when more discharging facilities are permitted at either of the mines.
"We're adding important new safeguards to ensure existing mines protect air and water quality near one of Arizona's most precious resources - the Grand Canyon - and we will be watching these facilities closely," said ADEQ Director Benjamin H. Grumbles.
The permits were issued after a thorough public process including a public event near the proposed Arizona 1 and Pinenut mine sites in Fredonia that included oral and written public comment, a public meeting with questions and answers, and a public hearing to accept oral comments with a court reporter and verbatim record. The Department responded in writing to all comments received.
ADEQ also conducted consultations with tribal leadership and members of the Havasupai Tribe in the village of Supai, with members of the Hualapai Tribe in the village of Peach Springs, and with members of the Kaibab Paiute Tribe in the village of Moccasin.
For more information, visit www.azdeq.gov/environ/air/permits/denison.html.