Resource and Energy Economics ( IF 3.553 ) Pub Date : 2021-05-23 , DOI: 10.1016/j.reseneeco.2021.101246 Sara Aghakazemjourabbaf , Margaret Insley
This paper studies the impacts of an environmental bond, which fully covers waste cleanup costs, on a mining firm's optimal actions over the full life cycle of a mine, when bankruptcy may shift cleanup costs to the government. A firm's stochastic optimal control problem is described by an HJB equation with the resource price modelled as an Ito process. A theoretical result shows that under certain assumptions, an environmental bond can ensure that the option to declare bankruptcy has no impact on the firm's optimal actions. A numerical solution is implemented for a hypothetical copper mine using two different models of bankruptcy risk. Numerical results show that when bankruptcy is an option and no bond is required, the firm produces too much waste relative to a benchmark case, resulting in an efficiency loss and a cleanup liability imposed on government. In the presence of bankruptcy risk, a bond ensures that the firm acts optimally and no efficiency loss is imposed on society.
中文翻译:
留下尾矿:环境债券、破产和废物清理
本文研究了完全涵盖废物清理成本的环境债券对矿业公司在矿山整个生命周期内的最佳行动的影响,当破产可能将清理成本转移给政府时。企业的随机最优控制问题由一个 HJB 方程描述,资源价格被建模为一个 Ito 过程。一个理论结果表明,在某些假设下,环境债券可以确保宣布破产的选择权对公司的最优行为没有影响。使用两种不同的破产风险模型为假设的铜矿实施了数值解。数值结果表明,当破产是一种选择并且不需要债券时,相对于基准案例,公司产生了过多的浪费,导致效率损失和强加给政府的清理责任。在存在破产风险的情况下,债券可确保公司以最佳方式行事,并且不会对社会造成效率损失。