Proposed In-Situ Copper Extraction Project in Florence, AZ

Florence, AZ, a small town with big dreams is being threatened by a mining operation in town. Since the mining operation is within the town limits, it does not have the exempt zoning status as in unincorporated ares. The town has adopted a General Plan, as required by State law, that was approved by the residents. The plan included a large development with a Del Webb Sun City and Pulte homes, both have invested millions to comply with the vision of the General Plan. However, one drawback has emerged—an in-situ copper mine in the middle of the area of the new developments. Curis (another Canadian company) has purchased the land in a foreclosure sale that BHP had attempted to mine some 20 years ago. Apparently, Curis did not consult with BHP, for they would have been told it was impossible to mine the site without polluting the water, although they state that they have hired people who worked on the BHP project. Ms. Tekla King, Brown and Caldwell, Mr. Jarrell Southall, Brown and Caldwell and
Mr. John Kline, Environmental Manager, BHP Copper have signed a letter from BHP to ADEQ.

Current Events: A Planning and Zoning hearing was held on Oct. 6, 2011 in Florence in regard to the changing of the General Plan to accomodate a mining operation that would be importing and storing and injecting chemicals into the groundwater. The hearing lasted over 8 hours until 2 a.m. The town residents turned out in full force to defend their community even though they had already attended a 5-hour hearing on the same matter on Sept. 15. They were remarkably well informed about the implications of the mining project. The hearing can be seen at http://www.florenceaz.gov/index.php?option=com_content&view=article&Itemid=420&id=782%3Aoctober-6-2011 .

History: The project had been attempted by BHP some 20 years ago, but they had given up due to the high uranium levels in along with the copper. The sulfuric acid solution would leach the uranium and other heavy metals, along with the copper. This type of leaching would require a closed aquifer, so that it would not enter the public water supply.

A report from BHP in 1999 outlines the environmental challenges: 26 exceedences of mandeated water quality levels. In situ mining requires a closed aquifer so that the chemicals used for leaching do not migrate to contaminate the surrounding water supply. BHP reported that communication between aquifers was determined to be the most likely cause for the exceedances.

The P &L Commission had already voted against the project, as it would require a change in the General Plan, required by the state, and approved by citizen vote. However, Curis came up with a second plan; that is, to obtain a temporary 20-year overlay, to complete the project and then return it to low impact industry and commercial zoning. Curis was represented by a land-use attorneys, Lake and Pew. Mr. Lake stated there would not be any toxic material residue from the processing, so he knew little about the environmental impacts.

Environmental Impacts: Although the illustration of the hydrology provided by Curis Resources in their General Plan amendment application shows a clay layer above and bedrock below, there is imminent danger of lateral movement of the acid off-site. Attached is a graph of the Curis on-site illustration and a graph of the expanded lateral hydrology, provided by Protect Our Water, Our Future group. See Hydrologly characteristics of the site.

A large local development, Merrill Ranch, was represented by land-use attorney, Paul Gilbert. He did understand environmental issues and presented relevant information with documentation on a power point of all his assertions, including the attached hydrology illustrations. He included records from ADEQ showing that Curis had failed to give appropriate information in some 78 instances in their APP application. One problem, which also bogged down BHP, is that there are hundreds of core sample drill sites, which probably penetrated to the aquifer, some of which cannot be located.

Water Pollution: One Curis attorney, Rita Maguire, gave a presentation stating that nineteen permits would be required by the state. However, she failed to mention that the ambient sulfate level is 84 mg/ltr. (source: Johnson Utilities), so the sulfate level and accompanying TDS would triple before the secondary standard could apply. However, Curis did disclose how much sulfuric acid would be going into the aquifer: five billion pounds. The additional chemicals they would be using were listed in the Aquifer Protection Permit: Chemicals to be stored on site. We know that in Green Valley, AZ the sulfate level reached 500 mg/ltr with the Total Dissolved Solids reaching being over 900 mg/ltr before any action was taken by the State. After 3 years of hard work it finally happened: ADEQ announcement of finalized Aquifer Protection Permit in Green Valley.

Water Depletion: Curis has failed to provide any information on the total amount of water they plan to use.Further, Ms. Maguire did not mention water depletion or any regulations about well spacing from existing public supply wells. We did find out that Curis' plans for commercial operation will require 480 to 600 injection and recovery wells per “operational unit”, with injection rates of 11,000 gpm for 20 years.

Land re-use: Over 1,000 well casings sites would make it difficult to recover the property after the mining operation for another use. Also, the residue from the processing would be left to dry in open impoundments, to be removed to a toxic waste dump. If it's not toxic, why wouldn't they be re-using it in their injections wells. There would be a continual threat to air quality and surrounding soil quality from any high wind events in the region.

The Commission vote was tied (2 to 2 with one not voting). The proposal will be heard the Town Council on Monday, Nov. 7, 2011 for their vote.

News from Florence Reminder and Blade:

July 19, 2012: Pinal Partnership board officially supports Florence

May 23, 2012 Arizona A.G. looking into Truth Squad

May 10, 2012 Gila River Council OK's resolution opposing mine

April 19, 2012 Study results point to significant benefits for Florence

(NOTE: Who paid for the study? Why do all university studies support mining?)

April 5, 2012 Town condemns Curis office for health and safety issues

March 1, 2012 Targets of flyers file election complaints

Feb. 2, 2012 If mine is safe, why more tests? opponents ask

Aug. 11, 2011 Ratcheting up the rhetoric

 

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