Science Applications, Inc. is submitting this technical discussion to DOE/LERC to explore the potential applications and benefits of using high pressure water jets to cut oil shale during the preparation of in situ retorts. If successful, this approach would provide a low cost method of framing the required void volume for expansion of the shale for retorting. This approach would have application to both Wyoming and Utah shales which may not otherwise be exploitable by modified in situ processing.