Lettis Consultants International, Inc. (LCI) offers high-technology, innovative Earth science consulting services to clients around the world. LCI geologists, seismologists, and engineers have comprehensive worldwide experience providing earthquake hazard analyses, engineering geology and geotechnical services, water resources expertise, and licensing and regulatory strategy and compliance. We have conducted numerous state-of-the-art studies in support of seismic analysis and design for critical facilities (pipelines, dams, nuclear plants, penstocks, hospitals, commercial buildings, bridges). Our professionals bring the methods, technical expertise and focus on quality developed from decades of consulting experience to meet our clients’ objectives in a manner that reflects our strong belief that good science and good engineering result in the best informed decision-making for facility owners and operators.
Seismic Hazard Software (THAZ)
LCI’s seismic hazard software THAZ is a comprehensive software package that performs state-of-the-art seismic hazard analysis, including;
- Calculating frequency of exceedence of ground motion amplitudes using the probabilistic hazard analysis framework;
- Incorporating site response analysis into the hazard results;
- Calculating hazard fractiles and hazard sensitivities;
- Performing hazard disaggregation;
- Representing the activity rate of areal sources as either spatially uniform or spatially variable; and
- Representing integrated hazard results with specific earthquake magnitudes and distances for facility risk evaluation.
THAZ is a QA verified and validated code that is capable of running the CEUS SSC model and 2004-2006 and 2013 EPRI ground motion models for probabilistic seismic hazard analyses (PSHA).
LCI Nuclear Quality Assurance program (NQAP)
LCI’s Quality Assurance Program (QAP) complies with the requirements of 10CFR50 Appendix B “Quality assurance criteria for nuclear power plants and fuel reprocessing plants.” All 19 criteria of Appendix B are included in the LCI QAP. The LCI QAP also complies fully with ASME NQA-1 (1994, 2008) requirements.