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Deep-sea polymetallic nodules are considered as animportant potential resource for Nickel, Copper, Manganese and Cobalt.The research has showed that they contain alarge variety of other metals, including molybdenum, zinc, zirconium, lithium, platinum,titanium, germanium, yttrium, and REEs, which increased the nodules combined value as analternative supplies for expanding economies, high technology and emerging green energy technologies.
The highest nodule abundance (more than 10 kg/m2) with the high average percentageof metals (at least 2.5 % content for Ni+Cu, 0.2% Co, 30% Mn, 0.15% Zn,0.07% Mo, etc.) were found at seafloor in the eastern equatorial Pacific (Clarion-Clipperton Fracture Zone, CCZ) and in the central equatorial Indian Ocean.

Within the recent decade, the International Seabed Authority (ISA) granted several national and multinational entities exclusive 15-years contracts for polymetallic nodules exploration in the claim areas, each covering75000 km2 in the international seabed area. The commercial viability of nodule mininghas yet to be established, but the size of deposits, the grade of several metals containedin nodules as well as the promising trends in metal market continue to motivatecontractors to carry out their exploration activity.

Ocean Mining for Environment
Polymetallic nodules are a source of metals for engineering conducive to the environment. Many modern devices are based on a highly innovative technologies. They are impossible to achieve without the use of copper, nickel, cobalt, manganese and other metals, which are found in the nodules.

Copper, as well as its alloys commonly accompany us in modern life and technically balanced civilization. Certain uses of it, such as for example plumbing, corrosion-resistant coating or food industry are obvious and visible to everyone. Copper is, however, of considerable importance in the development of emerging green technologies. Copper has excellent characteristics of current conducting hence, its great role in energy production by means of the advanced methods for a modern but sustainable society. Unconventional methods of renewable energy production, require the development of innovative technologies for the collection and processing of various forms of energy. Generating the same amount of energy with the help of a modern wind turbine compared to a power industry based on fossil fuels, requires the application of even a dozen or more copper in the case of the wind turbine. The percentage of copper in the terrestrial deposits decreases, and the high concentration of this metal in nodules provides the potential for the efficient and sustainable management of subsea deposits. Copper has a key role in the efficiency of energy - it is estimated that the prudent use of one tone of copper in the energy sector, may radically reduce the CO2 emissions by up to 200 tons per year.

Nickel, is used primarily for the production of corrosion resisting steels, protective and ornamental coatings and special super-alloys used in efficient, cutting-edge and cost-effective engines with low emissions and low specific fuel consumption. The future use of nickel is primarily ecological nickel-metal hydride battery. The batteries what is innovative, do not contain toxic cadmium compounds as rechargeable nickel-cadmium batteries and have one of the highest energy densities. Nickel foams are applied to the production of the alkaline fuel cell (AFC). The AFC is one of the complex, most highly-developed fuel cell technology. They use solely hydrogen and pure oxygen to produce electricity, water and heat. Alkaline fuel cells based on nickel foams is a technology completely fulfilling the expectations of a future sustainable energy conversion technology. This technology has such features as for instance, high efficiency electric trace emissions, the possibility of use the cogeneration processes and materials applied in its construction are environmentally friendly.

Manganese is an element, primarily without which it is impossible to manufacture durable and lightweight steel, used for example, in the engineering of transport means. Its use vastly reduces fuel consumption, CO2 emissions and make possible the high energy efficiency operations. Potassium permanganate (Potassium permanganate) is applied in cutting- edge, external water treatment processes. In the situation of its universal accessibility is relevant to the development of civilization in countries with restricted access to water.

Cobalt is a component of alloys resistant to very high temperatures, which enhances the progress of low-carbon technologies with high thermal efficiencies. What is more cobalt is the innovative material used for the sophisticated construction of catalytic converters applied in the process of hydrogen generation.

Sustainable development of the progressive engineering based on advanced science requires a constant metal supply, contained in polymetallic nodules. Deep ocean mining, is therefore an unconventional, forward-thinking, technologically advanced, alternative sourcing of raw materials for environmentally friendly technologies. The innovative process of extracting deep-sea minerals from the point of view of the environment, is more favourable than the mining operations, conducted on land-based deposits.

Firstly, in the case of the ocean mining, there is no risk of disruption of the social structure in the area for work. Such a risk is always there when the mining operations are on land. The land mines, especially open-pit type, occur in a large area anddeeply interfere in the social and environmental system. Changes may even lead to a regional loss or degradation of the local cultural societies. Notwithstanding, this threat does not occur in the case of the highly-advanced ocean mining.On the contrary, in accordance with the planned mining licensing policy, cooperation between the IOM and the International Seabed Authority UN may include a hybrid social business model (Hybrid Social Business - HSB). The HSB business model is based on the benefits for the mankind, a positive social impact as well as promoting progressive, sustainable human development programs.

Another vitally important factor in favour of the deep ocean mining is that the deposits lie directly on the seabed. There is no need for conducting such devastating operations as pre-strip. Operations of this type in the case of the land mining can lead to a significant environmental devastation and the destruction of the landscape on a regional scale. Ocean deposits are polymetallic-type with greater metal content than terrestrial deposits which give significantly more advantageous extraction efficiency. In the case of terrestrial deposits mean values of copper in the ore are now 0.5%, whereas in the polymetallic nodules there are two times more of it. The deposits of lateritic nickel ores are mainly located in the equatorial belt, so the development of the mine often leads to degradation and equatorial rainforests.

In the case of innovative technology of the ocean mining the engineering methods will be more advanced and efficient than usual. The use of ships and oil platforms ensures the high efficiency of the process. After completion the project provides one of the most advanced, optimal possibilities for reuse or recycling of materials.

The IOM during his long research activities, has thoroughly studied the environmental background as well as the potential impact of mining on marine organisms. Geological data concerning the abundance of the nodules and economic pre-feasibility studies prove that the real mining works will concern only a fraction of the area which is the subject of the contract with the ISA. The nature of the deposit guarantees a large amount of area not affected by mining. It strongly promotes the preservation of a vital biodiversity of the Clarion-Clipperton region.

The Environmental Management Plan for the Clarion-Clipperton Zone approved by the Decision of the 18th Session of the International Seabed Authority introduces 9 zonesof particular environmental interest, which together hold a surface areamany times greater than the surface of the potential mining. Additionally, the IOM in accordance with the ISA standards, has introduced the impact reference zone and preservation reference zones within its research area.

In these areas a pioneering, constant monitoring of factors which might affect the environment, will be conducted. Such a widespread activity of providing advanced technical assistance to the environmentally sustainable exploitation of marine resources has no visible equivalent in other types of the natural resources exploitation.

The Interoceanmetal has for a long time been carrying out a scientific research strictly related to the formal, experimental evaluation of the mining impact on the environment. The long-term studies involving the creating of stress on the benthonic environment, have been conducted between the year of 1994 and 2000. The BIE (Benthic Impact Experiment) experiment was carried out at a depth of 4200-4500 meters with a test of excitation of plume of sediments and strong physical impact on the bottom layer, using disturber of the same type as a collector potentially used for mining process.

The following have been studied:

disturbance thickness,
suspension and re-settlement of sediment,
near-bottom currents characteristics,
changes in the sediment properties,
pore waters chemistry (nutrients and heavy metals),
biological response to the disturbance.
Results of the advanced research did not show the threats from the experiment to the biodiversity in the area. Upon a completion of the BIE experiment, this region is periodically monitored during many research cruises. It is planned to obtain an additional data during the next cruise in 2014.

Nowadays, the IOM has been conducting numerical studies on the spread of the sediment plume particles, in the course of mining operations from the sediment excavated with nodules. This might be in particular one of the elements indicated as an potential risk for the natural environment. Preliminary results suggest a quite fast fading of the sediment plume in time. However in parallel, advanced conceptual design works on the closed-circulation type vertical transport system are carried out. This should reduce the risk of discharge to minimum. Moreover, the potential for the application of biorenewable and degradable biopolymers as modifier for a rheological and sedimentation characteristics of the slurry and sediment plume is under investigation.