In June 2009, the New York Times published an article about the public fear of geothermal development causing earthquakes. The article highlighted a project funded by the U.S. Department of Energy's (DOE) Geothermal Technologies Program bringing power production at The Geysers back up to capacity using Enhanced Geothermal Systems (EGS) technology. The Geysers geothermal field is located two hours north of San Francisco, California, and therefore, the article drew comparisons to a similar geothermal EGS project in Basel, Switzerland believed to cause a magnitude 3.4 earthquake. In order to address public concern and gain acceptance from the general public and policymakers for geothermal energy development, specifically EGS, the U.S. Department of Energy commissioned a group of experts in induced seismicity, geothermal power development and risk assessment to write a revised Induced Seismicity Protocol. The authors met with the domestic and international scientific community, policymakers, and other stakeholders to gain their perspectives and incorporate them into the Protocol. They also incorporated the lessons learned from Basel, Switzerland and other EGS projects around the world to better understand the issues associated with induced seismicity in EGS projects. The Protocol concludes that with proper study and technology development induced seismicity will not only be mitigated, but will become a useful tool for reservoir management. This Protocol is a living guidance document for geothermal developers, public officials, regulators and the general public that provides a set of general guidelines detailing useful steps to evaluate and manage the effects of induced seismicity related to EGS projects. This Protocol puts high importance on safety while allowing geothermal technology to move forward in a cost effective manner. The goal of this Protocol is to help facilitate the successful deployment of EGS projects, thus increasing the availability of clean, renewable and domestic energy in the United States. Project developers should work closely with the National Environmental Policy Act (NEPA) compliance officials of the involved Federal agency(ies) to align information needs and public involvement activities with the NEPA review process. The authors emphasize this Protocol is neither a substitute nor a panacea for regulatory requirements that may be imposed by federal, state or local regulators. I would like to acknowledge everyone who gave their time and expertise at the induced seismicity workshops (see Appendix D) that led to this updated Protocol. Their input was critical to develop an informed and useful document. In addition, I would like to thank the authors of this document, whose ideas and support came together to write a clear and concise Protocol. This document was put out for public comment and reviewed by NEPA, the U.S. Department of Energy and General Counsel. Special thanks to Christy King-Gilmore and Brian Costner for their guidance.

Probabilistic seismic hazard analyses were conducted to estimate both ground motion and fault displacement hazards at the potential geologic repository for spent nuclear fuel and high-level radioactive waste at Yucca Mountain, Nevada. The study is believed to be the largest and most comprehensive analyses ever conducted for ground-shaking hazard and is a first-of-a-kind assessment of probabilistic fault displacement hazard. The major emphasis of the study was on the quantification of epistemic uncertainty. Six teams of three experts performed seismic source and fault displacement evaluations, and seven individual experts provided ground motion evaluations. State-of-the-practice expert elicitation processes involving structured workshops, consensus identification of parameters and issues to be evaluated, common sharing of data and information, and open exchanges about the basis for preliminary interpretations were implemented. Ground-shaking hazard was computed for a hypothetical rock outcrop at -300 m, the depth of the potential waste emplacement drifts, at the designated design annual exceedance probabilities of 10-3 and 10-4. The fault displacement hazard was calculated at the design annual exceedance probabilities of 10-4 and 10-5.

S U M M A R YWe present a physically based methodology to predict the range of ground-motion hazard for earthquakes along specific faults or within specific source volumes, and we demonstrate how to incorporate this methodology into probabilistic seismic hazard analyses (PSHA). By 'physically based,' we refer to ground-motion syntheses derived from physics and an understanding of the earthquake process. This approach replaces the aleatory uncertainty that current PSHA studies estimate by regression of empirical parameters with epistemic uncertainty that is expressed by the variability in the physical parameters of the earthquake rupture. Epistemic uncertainty can be reduced by further research. We modelled wave propagation with empirical Green's functions. We applied our methodology to the 1999 September 7 M w = 6.0 Athens earthquake for frequencies between 1 and 20 Hz. We developed constraints on rupture parameters based on prior knowledge of the earthquake rupture process and on sources within the region, and computed a sufficient number of scenario earthquakes to span the full variability of ground motion possible for a magnitude M w = 6.0 earthquake with our approach. We found that: (1) our distribution of synthesized ground motions spans what actually occurred and that the distribution is realistically narrow; (2) one of our source models generates records that match observed time histories well; (3) certain combinations of rupture parameters produced 'extreme,' but not unrealistic ground motions at some stations; (4) the best-fitting rupture models occur in the vicinity of 38.05 • N, 23.60 • W with a centre of rupture near a 12-km depth and have nearly unilateral rupture toward the areas of high damage, which is consistent with independent investigations. We synthesized ground motion in the areas of high damage where strong motion records were not recorded from this earthquake. We also developed a demonstration PSHA for a single magnitude earthquake and for a single source region near Athens. We assumed an average return period of 1000 yr for this magnitude earthquake and synthesized 500 earthquakes distributed throughout the source zone, thereby having simulated a sample catalogue of ground motion for a period of 500 000 yr. We then used the synthesized ground motions rather than traditional attenuation relations for the PSHA.In this paper, we present a physically based methodology to predict a range of ground motions at a particular site that may occur from a particular magnitude earthquake along a specific fault or within a specific source volume, and demonstrate a means to incorporate this into traditional probabilistic seismic hazard analyses (PSHA). The prediction methodology is based upon the work first presented by Hutchings (1991Hutchings ( , 1994 and further developed by . The physical model proposed by the previous studies has been further developed in this study and the methodology expanded to include PSHA. We apply the methodology to the M w = 6.0, 1999 Athens earthquake. The full methodology i...

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The Advanced Tokamak capability of the FIRE burning plasma experiment is examined with 0D systems analysis, equilibrium and ideal MHD stability, RF current drive analysis, and full discharge dynamic simulations. These analyses have identified the required parameters for attractive burning AT plasmas, and indicate that these are feasible within the engineering constraints of the device.