An Environmental Impact Assessment Framework for Space Resource Extraction

Abstract

Extraterrestrial bodies contain a number of resources that are likely targets for future resource extraction operations. There is an increasing interest in extracting resources from these bodies, particularly to reduce the amount of material that must be launched from Earth and, in turn, the cost of space missions. While the economic and technical feasibility of space resource extraction is the focus of many studies, this work considers the associated extraterrestrial environmental implications. Resource extraction in space is likely to result in a number of environmental impacts, ranging from the generation of dust and changes to landscapes, through to regolith contamination and waste generation. A framework for extraterrestrial environmental impact assessment (EIA) for resource extraction operations is proposed for space resource projects. This framework will allow for the environmental impacts of potential space resource extraction projects to be identified, so they can be avoided or addressed through mitigation measures. Carrying out EIAs for space resource extraction operations is likely to improve the outcome of these operations by reducing environmental risk, and thus reducing the potential for unexpected clean up and mitigation costs in the future, increasing investor confidence and improving chances of acceptance by the public and other stakeholders. There is considerable uncertainty as to what impacts space resource extraction is likely to have on the environment, therefore the proposed EIA framework is intended to be improved upon continually, through feedback from the outcomes of future resource extraction projects.

Introduction

If humanity could start over again, we would likely wish to make wiser choices when it comes to protecting the environment. As we work towards further exploration of celestial bodies, we have the opportunity to apply the knowledge and experience learned from Earth to protecting the extraterrestrial environment. Extraterrestrial bodies, such as asteroids, Mars and the Moon, are an untapped and potentially abundant supply of resources, which may have many uses in space, and, eventually perhaps, on Earth. There are a number of public and private enterprises that have expressed interest in extracting these resources, leading to concerns about a lack of governance and regulation over the extraterrestrial environment [1]. Continued exploration of space, and especially establishing further human presence in space, requires a vast amount of resources. Many of these are already available as natural resources in space, and a number of in-situ resource utilisation (ISRU) schemes have been proposed to extract resources, such as water, for use in space (e.g., Ref. [2]). Motivations for extracting space resources may go beyond human space travel and colonisation, with private organisations evaluating the potential of extracting resources that are becoming increasingly scarce on Earth from space, such as platinum group metals. These resources would then be brought to Earth for use, should it become economically feasible to do so (e.g., Ref. [3]). Although a number of studies have investigated the technical and economic feasibility of extracting resources in space, many of them do not identify and assess the potential extraterrestrial environmental impacts, leading to calls for an environmental protocol for managing these extraterrestrial activities [1,4,5]. Particularly, as the private space sector continues to grow, it is clear that there is no shortage of ambition or excitement surrounding the exploration of outer space. However, as noted by Lin (2006) [6], there is also increasing concern about environmental risks and conservation. Newman [7] notes that a failure to address potential issues in the extraterrestrial environment arising from human activity could have serious implications for space activities in the future. This highlights the importance of extraterrestrial environmental management, ideas for which, have been proposed by several studies (e.g., Refs. [[8], [9], [10]]).

Environmental impact assessment (EIA) is an environmental management tool, which is used to assess the potential environmental consequences of a particular project or action. It has been successfully applied on Earth across a range of projects from mining operations through to assessing impact of space launches on Earth's environment [[11], [12], [13]]. The use of EIA spans many decades, and it has been applied in a number of countries across the world, as well as to address transboundary environmental impacts (e.g., Refs. [14,15]). Because of this, we have identified EIA as a tool with potential to support decision-making and environmental management of off-Earth mining (OEM) operations. EIA provides a means to identify and predict the potential extraterrestrial environmental impacts associated with OEM. This allows for mitigation measures to be developed and put in place [16]. In addition, the comparison of alternative courses of action and stakeholder engagement in the decision-making process are important aspects of the EIA process.

The definition of OEM used in this context is that of Shishko et al. [17], which is the extraction of minerals, volatiles (hydrogen, helium, water oxygen) and other indigenous resources from the Moon, Mars, asteroids and comets. OEM can be divided into three broad categories: resource extraction for use in-situ in space (known as in-situ resource utilisation [ISRU]), resource extraction for use in space (but not in-situ), and resource extraction for use on Earth. ISRU is a term collectively used to describe the process of extracting and processing resources from celestial bodies and utilising the products in space. The key aim of extracting resources in space is to produce consumables for human space missions and space settlements, including rocket propellants, life support gases, reactants for energy production and materials to manufacture infrastructure [18]. The extraction of space resources would lead to considerable reductions in the mass that would be required to be launched from Earth for space missions, so if a spacecraft bound for Mars could refuel near the Moon or a near-Earth asteroid, for example, it would result in significant monetary savings compared to travelling directly from Earth. At present, the main focus of ISRU research is the extraction of volatiles from ice, regolith, and in the case of Mars, the atmosphere [2,19,20]. ISRU is currently the primary focus for OEM, as extracting resources in space for return to Earth, is, at present, not financially viable [21]. Although not yet economically viable, there has been considerable discussion about the potential to someday extract resources in space for return to Earth (e.g., Refs. [[22], [23], [24]]). Metals like platinum and palladium that are relatively rare on Earth and abundant in asteroids are likely to be targets for future resource return operations [25].