a) Generally

a2) Abandoned mine sites as secondary deposit

The height of the costs for safe and sustainable closure of mining facilities are determined with the planning of mining project. Naturally also the opening and mining methods, the surface facilities and mine site infrastructure, the management of stream of mined material, the placement and operation of mills and tailings storage facilities and the age of mine site do determine the costs of mine closure significant. The closure plan of mining legacies have to be an integral part of project planning, its costs included. The closure costs for the abandoned mining (legacies of uranium ore mining) are generally essential higher as for new mine developments, see figures below.

Advice: The uranium price is denoted with 79,25 US$/lb as of 2024-08-30 Source: Ux Consulting Company, LLC, from Sept 2018: Uranium (Globex) - Futures Charts    Ux U3O8 price

b) Requirements on abandoned mine sites reclamation

In order to be able to define the requirements to the reclamation and remediation of abandoned mine sites, the site characterisation is required. Data on site properties and conditions form the basis for current environmental assessments, risk analyses, decommissioning plans, reclamation programs, monitoring programs and final public use of the sites. The quality scopes as well as the procedures for the quality assurance and for quality control [QSP (QC/QA)] can be introduced only when if all location characterisation are present. The quality goals as well as the procedures for the quality assurance and for quality control [QSP (QC/QA)] can be introduced only then if all site characterisation was collected.

Many site factors can influence the reclamation of a mine site:

- Topography, geology, hydrology, hydrogeochemistry, climatology, ecology, operating characteristics, description of radiological    characteristics and socioeconomic characteristics (Social impacts)

- The hydrological and hydrogeochemical characterisation included identification of aquifers, impermeable-strata and depth to water   tables, groundwater contours, hydraulic gradient and flow rates, ground and surface water quality, and changes in surfaces- and  groundwater characterisation over time

-  A mine site (especially uranium mine site) operational and radiological characteristics are prime importance in its reclamation and   remediation

-  Also prime importance is the knowledge how the mine operated for reclamation strategy and the use of reclamation methods and  equipment

-  The geotechnical aspects of the mine (in context with radiological properties), including its stability, will help determine if certain   reclamation options will endanger the workers, and radiological characteristics determine how much reclamation must be conducted

-  The natural background of radiation on special mine site is very important for the development of the closure plan

-  Not to the end, understanding the fauna and flora in the area is very important if the reclamation ought to be good.

Each mine site is unique!!! Each mine closure plan is therewith also unique!!! This basic realization is not new to consider but again and again on the new. The mine closure plans and also the therewith closely connected costs are so comparable and transparent, world wide.

The following  basic philosophy becomes for the mining remediation a further sticking point:

„Have got an effective mine closure plan, follow it and examine it again and again, in particular at the interfaces of the project. Be ready, if necessary, to change the mine closure plan, if the mine closure works ought to show a optimal outcome.”

b1) Mill tailings storage facilities reclamation

The financing of the mine sites reclamation as well as permission, control, project management, execution of the remediation works (included the engineer works) are differently organized in the individual mining countries. A basic organization can be recognized however.

Partner with the closure of abandoned mining and milling sites:

- Independent, public requirement authorities and controlling authorities , also independent project management

- Placing of decommissioning works  (included engineering works) to the companies, development of final closure plan

- Examples: USA, Canada, Australia, Germany, of it  substantially differed in some fields

The mill tailings and their deposit are defined and licensed by the authorizing agencies. The remediation of tailings storage facilities is closely affiliated with the remediation of mine sites, especially of uranium mine sites. Framework guidelines exist in many mining countries, especially framework guidelines for requirements of remediation for tailings storage facilities. These determine to a large extent the costs for the mine site closure. Exemplary the USA are specified here:

Decommissioning of uranium tailings storage facilities follows the environmental protection standards of Environmental Protection Agency (U.S. EPA), and licensing and closure regulations and Guidance of  U.S. Nuclear Regulatory Commission (U.S. NRC) and/or its Agreement States.  The requirements of Department of Energy (DEO) and of Uranium Mill Tailings Radiation Control Act (UMTRCA) are considered in the framework guidelines. Here some documents are specified:

- Standard Review Plan for The Review of a Reclamation Plan for Mill Tailings Sites under Title II of the Uranium Mill Tailings Radiation Control Act of 1978 (U.S. NRC 2004)

- Standard Review Plan for In Situ Leaching Uranium Extraction License Applications (U.S. NRC 2003)

- Design of Erosion Protection for Long-term Stabilization (U.S. NRC)

- Office of Nuclear Material Safety and Safeguards (NMSS) Decommissioning Standard review Plan (U.S. NRC 2006b)

In addition to the tailings storage cover or backfilling of tailings are the water gathering systems, the water treatment plants (alternative or supplementing permeable reactive walls, funnel and gate) as well as the ground-water protection (water protection) the cost-forming factors of the tailings storage facilities reclamation.

b2) Technology of dry in situ cover described as follows:

The tailings are pumped in the tailings storage as slurry. The tailings settle down and consolidate with the covering and over time. To acceleration of consolidation and to lower the water content are inserted vertical wick drains in the tailings-body (improvement of drainage, AMD), see Cofra BV.

-          An alternate way of enhancing dewatering of the tailings is to apply a thin layer of high-density cover material. For example, using a layer of synthetic geotextile and an iron netting increases the surface stability and prevents cracks by compressing the tailings to expel water, see Naue GmbH & Co. KG. In relation with inserted vertical wick drains and with layers construction it is possible to reach a acceleration of consolidation and settlement decrease.

-          The profiling of contour, the landscape design and the final capping needed a best practice of material management. The height of costs for closure works  considerable be influenced by both availability  and as well as characteristics of material. If possible waste rock be used. Finally the requirements to the material are determined by the necessity of limitation of the mobility of acid mine water and of the mobility of the radionuclides, by revegetation and maintenance of closure construction. Especially the requirement to the material are determined of long-life radionuclides and of decomposition products and their quantity and their location in the tailings-body.

Many mill tailings impoundments have simply been capped with dry rock (often waste rock material) without  revegetation, especially in case of not radioactive tailings storages.

The defined maximum concentrations (quality goals) as well as the stewardship of reclaimed areas and the Long-term monitoring have substantial influence on the total costs. Due to not uniform requirements into the German states, some demands of USA are  specified here exemplary. Under UMTRCA requirements, reclaimed uranium tailings storage sites are licensed to the DOE and designed for 1000 years of control.

c) Financing and closure costs for abandoned mine sites

c1) Example for 100% financing by mining company

In the costs presentation and costs comparison should be a difference in ore mining and milling and in uranium ore mining and milling, because the reclamation or the reduction of radiological mining legacies are a special challenge. Of course, are the requirements on the reclamation and remediation for closure of ore mining legacies otherwise the same.

c2) General closure costs presentation for special abandoned mine sites

Of course, each mine closure project is a unique project and is reclaimed with a final mine closure plan, which was developed alone for the abandoned mine site. A even so, which mining procedures and methods, which are used, are world wide similar. Its costs  are so comparable. Because the costs for the necessary closure of abandoned mine determine the efficiency of the mining company, their height determine also, whether a mining project will be started or not. This is the reason, because  the mining industry and the closely connected closure of abandoned mine site as an innovative business field have developed. The description with 3D - Dirty, Dark and Dangerous - for modern mine sites is this not true. The necessity more and more quantity of raw materials to keep ready, at the same time to deal carefully with resources, the mining industry and the closely connected closure of abandoned mine sites were made thereby new demands.

d) Presentation of closure costs for legacies uranium mining and uranium milling sites

     of special mining countries

    and examples

The uranium price has increased distinctly since 2004 [Ux Month-End Spot Prices: March 2004 = 17,50 USD/lb and March 2009 = 42,00 USD/lb]. Nevertheless it is not to be misjudged that after the hype in July 2007 [Ux Month-End Spot Price: July 2007 = 136,00 USD/lb], a distinctly decline in prices have to be recorded. This can not be attributed to the present financial crisis. Rather, this is to lead back to the fact that in the meanwhile production capacities would enlarged distinctly. Apart from the fact that the production capacities go back again. But, both for reasons of environment and for reasons of economy a low uranium price always is unreasonable. It is to hope that the uranium price stabilizes itself in the future on acceptable level. See also bottom uranium price development and annual produced quantities of uranium by mining.

Facts:

Thus the world-wide mined uranium amount was increased by 4,7% of 2006 on 2007. For 2008 Kazakhstan planned to increase the uranium production on 9.400 t (whether this was reached, up to now be unknown). The uranium production should increase to 12.826 t for 2009 and starting from 2010 annually to 15.400 t. Thus Kazakhstan would ascend to the world-wide largest uranium producer, who would mine approx. 37% of the annual world uranium amount. Unbelievably. In 2019, Kazakhstan produced 42.50% of the world's mined uranium, see table below !!!

Here presented costs of closure for mine closure are not complete, but controlled sampling.

The here presented costs for mine closure are calculated on basis of financing of mine closure works by public funds. The mining companies often not disclosed their mine closure costs. In Canada the often used financing method is the financing of abandoned mine site closure to share in two parts. One share by commercial funds the other by public funds- private-public partnership. Thereby the Canadian costs of abandoned mine site closure are not presented here. The reason for the limitation on the closure of abandoned uranium mine sites is because the costs of this closure works are very high in comparison to other mine closure works.

a1) Hazards recognize, which from the closure of mine sites come out and expel these longterm safe

See also category: Tailings ponds

Uranium price development, to enlarge click on it