Mining means extraction of valuable minerals. It is the extraction of valuable minerals or geological materials from the earth crust which forms the mineralized package of economic interest to the miner [1] [2] . There are four main stages associated with any mining project, which are: mineral exploration, actual mining, mineral beneficiation and project decommissioning (rehabilitation) [3] . The first stage involves all activities related to searching for valuable minerals that can be mined at a profit. These include area selection, target generation, resource evaluation and reserve definition, all of which aim at defining a mineral reserve with a high confidence level in order to allow a profitable mining project to be undertaken [3] . All the other three stages depend on the first stage (mineral exploration) for their existence.

Exploration means search for resources. Exploration is the act of searching or travelling a terrain for the purpose of discovery of resources [4] . Mineral exploration involves the search for mineral accumulations which can be profitably mined [3] . According to [5] , mineral exploration is the process undertaken by companies, partnerships or corporations in the endeavor of finding ore (commercially viable concentrations of minerals) to mine. It may be defined as the activities of evaluating a geologic prospect to determine its size, shape, grade, and profit potential [2] . Mineral exploration is a much more intensive, organized and professional form of mineral prospecting and, though it frequently uses the services of prospecting, the process of mineral exploration on the whole is much more involving. Every new mine must undergo mineral exploration before its economic viability can be established.

Unfortunately, the extent of the significance of the impacts of mineral exploration activities to the environment is not very clear to a number of stakeholders [3] . This is possibly due to the fact that exploration activities are either not very much understood or being ignored [3] [6] [7] . In the context of environmental management, mineral exploration can be divided into three main phases; the first phase is area selection that involves activities such as geological literature studies, map compilation, geological field studies and land acquisition. This initial phase is believed to have almost zero impacts due to the fact that all activities involved are either office work or half office and half field visit. The second phase is target generation which involves sampling through geophysical methods, geochemical methods and remote sensing. This phase is believed to have minimal and short term impacts that can all be reversible since it involves low-flying aircraft and few earth disturbing activities such as trenching and pitting. These activities are field based and are always associated with hydrocarbon spillage (minimal use of light vehicles and other smaller machines), few leftovers such as sample bags, food remains, and fuel drum [3] . The third phase involves detailed studies for assessment of mineral deposits through resource evaluation and reserve definition. This stage has very significant environmental and social-economic impacts (depending on the life span and the size of that particular exploration project). Activities such as drilling of boreholes (both core samples and rock chips drilling), trenching, site clearance, camp construction and the increase in the number of workers at site may cause substantive environmental impacts including air, water, noise and land pollution, disturbance to flora and fauna, camp garbage, hydrocarbon spillage, generation of metallic and plastic scrappers at site, land alienation, erosion as well as acid mine drainage [3] .

As it has been defined earlier, mineral exploration simply means “the search for mineral resources” while mining means “the extraction of resources”. Mineral exploration is usually performed before mining and in that way mineral exploration stands as an independent project that may or may not result into a mining project [8] . The only major difference between the two is that a mineral exploration project has a shorter lifespan (usually 4 years) compared to a mining project that may take up to 25 years. Also, the former is normally regarded as a temporary endeavor while the latter is considered permanent. Unlike mining projects which have several tools for their environmental assessment, exploration projects in Tanzania lack such tools. In the mining projects, there are special tools such as Environmental Impact Assessment, Environmental Audit, Environmental Accounting, Environmental Management and Monitoring and many other [9] [10] . The situation is different when it comes to exploration projects. There are neither special tools nor mandatory requirements that may offer a methodological guide for environmental assessment in the exploration projects.

This research work intends to analyze the current environmental regulatory framework on mineral exploration projects in the United Republic of Tanzania (URT). In line with that, this study shall use data from other studies conducted on one Uranium exploration project (in URT) to discuss environmental challenges that may arise during minerals exploration. Finally, this study reviews environmental regulatory frameworks from other few countries in comparison with existing environmental regulatory framework prevailing in URT.

The principal Act that regulates all mining (including mineral exploration) projects in URT is called the Mining Act, 2010 [11] . This principal legislation was then equipped with regulations, providing for its clear guidance for administration and enforcement. The regulations that are associated with the Mining Act, 2010 are known as “The Mining (Environmental Management and Protection) Regulations, 2010” [12] . Likewise, all environmental aspects in all projects, before and after their commencement are regulated according to the Environmental Management Act, 2004 [9] and the Environmental Impact Assessment and Audit Regulations, 2005 [10] . This act triggered the establishment of the National Environment Management Council (NEMC) that was then given power to undertake enforcement, compliance, review and monitoring of environmental impact assessment and in that regard, to facilitate public participation in environmental decision making, exercise general supervision and coordination over all matters relating to the environment. In 2005, the Environmental Impact Assessment and Audit Regulations were made. The document provides all the necessary requirements, steps, procedures and guidelines to be followed by an individual or organization wanting to undertake a project that might cause adverse impacts to the surrounding environment once undertaken, be it small, medium or large scale. The document also outlines a list of all projects that require undertaking of both Environmental and Social Impact Assessment (ESIA) and Environmental Management Plan (EMP) [13] . Unfortunately, mineral exploration projects are not discussed thoroughly in any of the two principal documents mentioned above.

Research [6] [14] - [16] has shown that mineral exploration projects may bring adverse impacts to the indigenous communities and the natural environment. This is the main reason for European countries i.e. Australia; and other African countries i.e. South Africa, Zambia and Zimbabwe have decided to consider mineral exploration projects as the type of projects that are likely to cause significant adverse environmental impacts to the communities, in and around the prospecting licenses [17] - [20] . Table 1 describes typical significant adverse impacts that are likely to be caused by each of the three main stages of a mineral exploration project.

Source: [3] .

In the last decade, significant Uranium ore reserves have been discovered in URT, welcoming potential investment opportunities for the establishment of new mining projects in the country [15] [16] . Taken as a case study, the Mkuju River Uranium (MRU) exploration project is one of potential mineral exploration projects that are expected to result into a mega mining project in the future [3] . Two independent studies were undertaken in 2009 and 2010 to assess the significance of adverse environmental impacts that were likely to be caused by MRU exploration project. Results of these two studies were reported in two different Masters’ Degree Dissertations in 2010 [3] and 2011 [7] consecutively. A review of the two studies has revealed the following important facts.

This study has revealed a significant loophole in the current regulatory framework in URT in relation to

^*Source: [11] [12] [22] ; Red highlight means “above the limits”.

environmental issues in the mineral exploration sector. Activities related to such projects may cause a significant detrimental impact to the natural environment if proper and timely measures are not taken. The fact that, the two principal legislative documents (Environmental Management Act, 2004 and Mining Act, 2010) that regulate both Mining and Environmental matters in the country are completely silent on this matter, adds more fuel towards the danger of destructions to our natural environment. Furthermore, studies by Wilfred (2010) and Mwalongo (2011) described in this report have vividly shown that mineral exploration activities may cause a significant level of negative environmental impacts. Not only that, but also other countries including Australia and other African countries earlier mentioned in this report provide further emphasis on the need for URT to improve its mining and environmental legislative framework to accommodate issues related to environmental protection in mineral exploration projects. To start with, mineral exploration projects should be listed in Type B projects stipulated in the Environmental Impact Assessment and Audit Regulations, 2005. This is a list of projects that require preliminary environmental assessment before they are undertaken. This category contains projects which are likely to have some adverse environmental impacts but that the magnitude of the impacts is not well-known. In this category, a preliminary environmental assessment is required to decide whether the project can proceed without a full environmental impact assessment or not.

Meserecordias Wilfred Lema, (2016) Analysis of Challenges Related to Poor Environmental Regulatory Framework on Mineral Exploration Projects: A Case of Tanzania. Journal of Geoscience and Environment Protection,04,89-96. doi: 10.4236/gep.2016.47010