\section{Introduction}
Uranium mines generate uranium oxide that is necessary to support the 390 operating nuclear reactors, supplying 10\% of the worlds energy \citep{worldnuclearassociation2024}. Uranium recovery facilities establish contracts with nuclear power plants to purchase set quantities of uranium in future years \citep{camecocorporation2024}.

The uranium mine industry, has undergone a technological innovation that shifts the method of recovery. Some companies have begun extracting uranium from groundwater aquifers. This in situ method was first tested in Wyoming at the Shirley Basin uranium project during the 1960’s \citep{mudd2001,worldnuclearassociation2022b}. This less intrusive extraction method has become the dominate means of uranium recovery the United States. Wyoming produced uranium entirely with conventional mining methods, until the early 1990s but now all mines use in situ techniques \citep{energyinformationadministration2023a}.

While in situ operations do not create as much surface disturbance, the process does increase the amount of dissolved constituents in groundwater. Some of these constituents can be toxic when consumed at high enough concentrations, such as selenium, and uranium. As a result rules propagated by the \ac{NRC} and \ac{EPA} create constraints on in situ recovery projects.

 One \ac{EPA} requirement is that the operation only takes place in low value reservoirs\footnote{The aquifer must be \emph{exempt} which is a \ac{EPA} classification that the aquifer wont be used as a public drinking water source, due to natural pollution, or low economic value}. At the same time \ac{NRC} rules require that after closure mines restore groundwater back to the original level of dissolved solid\footnote{At least 13 constituents are tested for and each independently must reach background levels}. On initial viewing these rules appear to create economically inefficient outcomes. Significant costs must be spent to restore aquifers that are already ruled to have a low economic opportunity costs. 

We seek to answer two questions relevant to policy makers. How do producers of uranium applying in situ technology respond to economic incentives? and; Are current \ac{EPA} and \ac{NRC} in situ regulations economically efficient?

To answer the first question a micro economic model of uranium in situ mining is created. This is used to inform a time series regression that estimates the short run and long run supply elasticities of uranium mining. This model is calibrated using production plan data from five Wyoming mines. The calibration is still a work in progress, but average values are used to provide preliminary results.

To determine if the current in situ regulations are efficient, the cost of regulatory compliance is estimated for each mine. Then assessor data on land values in uranium bearing regions is collected. Under a hedonic pricing model, the value of amenities such as aquifer quality are captured in land sale prices \citep{rosen1974}. By comparing these costs to the value of land in a typical mine, it is found that the net present cost of compliance are 4.5 times larger than the total land value. 

A qualitative review of the regulatory impacts are also provided, which will be built into a quantitative analysis in later work. The structure of in situ mines makes externalities caused by nearby aquifer contamination unlikely. On the other hand, the recovery process required by the \ac{NRC} and \ac{EPA} does create some minor externality costs. 

A analysis that robustly answer these questions is still in progress, and the current estimates are preliminary. However, the results do answer these questions. To our knowledge this is the first economic model of uranium in situ mines. Based on these models dead weight loss from the regulations is expected. The average cost of aquifer remediation is 15 million dollars per Wyoming uranium in situ mine. Most of this is a dead weight loss providing a lower bound estimate of the policy inefficiencies. We also identify a untended consequence of the restoration requirements, that existing mines extract uranium for a longer period of time. This non-obvious policy outcome results in the water remaining polluted for a longer time period.
