TENORM Potential Killer or Potential Snag for Rosemontby Robert Harris on Sep. 04, 2011, under copper mining, Rosemont copper, Tucson
TENORM, an acronym for a process as dangerous as it is mysterious. The entire name of it is, ” Technologically Enhanced Naturally Occurring Radioactive Material”. A well-known phenomenon by the agencies that are supposed to protect the citizens from environmentally hazardous material.
The subject was brought to the attention of the forest service during the scoping comments on the proposed open pit Rosemont copper mine in the Santa Rita mountains. An example was also pointed out in relation to the uranium plume in the Green valley neighborhood. So far I can find no example of the subject being discussed in any of the freedom of information act documents released by the forest service.
At a recent meeting in Corona De Tucson a representative from Pima County Department of environmental quality stated his primary objective was to evaluate dust control. References were also made to the limited number of personnel available. If their primary concern with the Rosemont copper proposal is a dust control then who is going to evaluate the potential effects of radiation enhancement? We are now at the beginning of public comments concerning the Pima County permit for the proposed open pit mine, perhaps we should inquire of the Pima County Department of environmental quality who is studying and evaluating this potential problem.
Following are some excerpts from that report compiled by the United States EPA and the Arizona Department of environmental quality. The data show that dump leaching operations and solvent extraction – electro winning procedures, as well as the practice of recycling raffinate at copper mines may extract and concentrate soluble radioactive materials, the results show increases of up to two orders of magnitude over background levels for all radio chemicals tested except R– 222.
Nearly all rocks, soils, and water contain small amounts of radioactive materials such as uranium, thorium, radium, radioisotopes of potassium, lead, polonium, and their decay products. When naturally occurring radioactive materials in their undisturbed natural state (NORM) become purposefully or inadvertently concentrated either in waste byproducts or in a product, they become technologically enhanced naturally occurring radioactive materials (TENORM). TENORM is defined as any naturally occurring radioactive materials whose radionuclide concentrations or potential for human exposure has been increased above levels encountered in the natural state as a result of human activities.
The EPA and other regulatory entities have become increasingly aware of the immense volume of TENORM produced annually throughout the United States. The potential threat posed by these wastes cannot be dismissed as below radiological concern or below exempt concentration levels. TENORM concentrations often reach levels comparable to typical low-level radioactive waste.
At the dead center of the patented mining claims owned by Rosemont copper, and more specifically dead center of the proposed open pit, there is an abandoned mine, the King mine. It is located in section 24, Township 18 S., range 15 E. and this mine is specifically noted in the report concerning TENORM.
The King mine is an old silver and copper underground operation south of Tucson. The mine is situated in a contact alteration zone, where pitchblende occurs with sulfide ores in quartz-calcite gangue in pockets along a limestone/quartz monzonite contact. Assays show uranium ranging from 0.14 to 0.93 percent. This number is it’s (NORM) natural state. The TENORM numbers after processing will be much higher.
The regulation of radioactive waste has generally been limited to the atomic energy act, the clean air act, the safe drinking water act, and the comprehensive environmental response, compensation and liability act
EPA has been working with the Arizona Department of environmental quality to assemble the available data on TENORM and metal mining sites in Arizona. As part of its groundwater and surface water protection programs, they require mining companies to submit aquifer protection permit applications that include facility specific radiological characterizations. As a result, ADEQ and EPA have accumulated in excess of 3200 analysis of radionuclides at 15 mining sites in the copper industry.
Levels in excess of the federal maximum contamination level and state guidelines were found in groundwater and surface water samples, as well as soil and sediment samples and abandoned and active copper mines. TENORM exceedances were also found in groundwater at active and inactive copper mines.
The solvent extraction process acts to concentrate TENORM. Technological advances in SX – EW procedures have created new waste streams that were not assessed in earlier EPA studies. The natural leaching process tends to extract and concentrate radioactive materials in the acid mine drainage at waste dumps. Dump or heap leaching operations also extract and concentrate the soluble radioactive materials.
The impacts of copper mining are noteworthy because of the unique conditions, such as the presence of trace uranium minerals and the mining and extraction methods that unintentionally extract radioactive materials and enhance its environmental mobility.
Several Arizona copper ore bodies are either too deep or are too low-grade to be mined by conventional surface or underground methods. There are several in-situ solution copper mines in the Arizona copper mining belt. High levels of TENORM have been found in the PLS of two in-situ leach operations in Arizona.
Typically, an in-situ copper mining company will be required to undergo a joint ADEQ-EPA permitting process. EPA issues a federally-administered Class III Underground Injection Control (UIC) permit and an aquifer exemption permit that focus on the subsurface injection and restoration activities. ADEQ initiates an APPA process that focuses on both subsurface activities and the surface facilities and impoundments.
A proposed operation must meet both of the following two criteria for an aquifer exemption: 1) the aquifer must not currently serve as a source of drinking water and 2) the permit applicant must demonstrate that the deposit contains minerals that are expected to be commercially producible. The permit covers the construction, operation, and eventual closure of the injection and recovery wells system and surface facilities and impoundments. The permit also defines the lateral and vertical boundaries of the proposed aquifer exemption.
This information and much more, a total of 124 pages, is available to the general public in report number EPA 402 – R – 99 – 002 .The US Environmental Protection Agency released report number EPA 402 – R – 99 – 002 in October of 1999.