September 1, 2017

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Geosyntec Staff to Present at Dam Safety 2017

Geosyntec professionals will present at Dam Safety 2017 at the J.W. Marriott San Antonio Hill Country Resort in San Antonio, Texas on September 10-14, 2017.

Melissa Setz (Georgia) will deliver a presentation entitled "Turning Disaster into Knowledge: Assessment of South Carolina Dam Failures Related to Offshore Hurricane Joaquin by the GEER Team," Lelio Mejia (California) will deliver a presentation entitled "Construction of Dam 1E For The Panama Canal Pacific Access Channel," Robert Bachus (Georgia) will deliver a presentation entitled "Similarities and Differences in Kingston compared to Tailings Dams and other Ash Ponds," Raphael Siebenmann (Georgia) will have a poster presentation entitled "Standardized Geotechnical Data Management and the Dam Safety Community," and Dan Schauer will be in attendance.

Geosyntec will also have a booth to meet with the presenters or for service and business inquiries.

The United States Society on Dams (USSD) Committee on Tailings Dams is partnering its workshop with the Association of State Dam Safety Official's (ASDSO) national conference, Dam Safety 2017.

ASDSO is a national non-profit organization serving state dam safety programs and the broader dam safety community, which includes federal dam safety professionals, dam owners and operators, engineering consultants, emergency managers, manufacturers, suppliers, academia, contractors, and others interested in improving dam safety.

Geosyntec Participation

Turning Disaster into Knowledge: Assessment of South Carolina Dam Failures Related to Offshore Hurricane Joaquin by the GEER Team
Presenter: Melissa Setz, Engineer, Geosyntec Consultants
Co-authors: Glenn Rix, P.E., Senior Principal, Geosyntec Consultants; Jeremy Varner, P.E., Civil Engineer, Federal Energy Regulatory Commission; and Hermann M. Fritz, Ph.D., Associate Professor, Georgia Institute of Technology

Extreme rainfall from offshore Hurricane Joaquin caused extensive flooding and the failure of important infrastructure across South Carolina (SC) in October 2015. Several areas experienced precipitation accumulation at a level that occurs once in every 1,000 years. The subsequent floods inundated large areas of SC, specifically around Columbia, and resulted in at least 19 deaths and over $10 billion of flood induced damage. Geotechnical Extreme Events Reconnaissance (GEER), an NSF funded program that investigates geotechnically important extreme events, formed a team to visit SC to document geotechnical issues associated with major flooding, including the failure of dams and damage to bridges.

The overall goal of GEER is to use information collected after a natural disaster to advance engineering practice and research. Extreme events engineering is an experience-driven field. Thus, it is critically important to systematically collect perishable post-disaster data that can be useful in advancing our understanding of extreme events when they happen. The SC GEER Team consisted of consultants (Geosyntec), university professors and students (Georgia Tech and Clemson), and a Federal Energy Regulatory Commission (FERC) representative, who participated in site visits to investigate: (i) dam and bridge failures; (ii) embankment breeches; (iii) a flooded open pit mining operation; and (iv) dam structures that withstood the flooding.

The SC GEER study included the observation of over 15 dams. The bulk of SC GEER observed dam failures were associated with privately owned and maintained (e.g., lake communities) dams. Multiple cases were observed where upgradient dam failures caused water to rush downstream and resulted in downgradient dam failures. The team also visited the Columbia Canal, a source of the City of Colombia's drinking water, which was breached. In addition to documenting site conditions and geotechnical observations, the team completed Unmanned Aerial Vehicle (UAV) surveys to create 3D models of select dam failures. This data is helpful for understanding how mass movements occurred and is a valuable tool for forensic-type analysis which can possibly aid in reconstructing failures. The main findings from the investigation are presented in a report posted on the GEER website,

Construction of Dam 1E For The Panama Canal Pacific Access Channel
Presenter: Lelio Mejia, Ph.D., P.E., G.E., Senior Principal, Geosyntec Consultants
Co-authors: James Toose, Principal Engineer, AECOM; and Jorge Fernandez, Project Manager, Panama Canal Authority

A new key element of the Panama Canal is the Pacific Access Channel, a 6.7-km-long waterway at the Pacific entrance to the Canal. The new channel provides navigation access from the new Post-Panamax locks to the existing Gaillard Cut section of the Canal and required construction of four dams, known as Borinquen Dams 1E, 2E, 1W, and 2W. The dams retain Gatun Lake, the main waterway of the Panama Canal, and are therefore critical to the operation of the Canal, to the economy of Panama, and to world maritime trade.

The dams were designed as rockfill embankments with a central impervious core flanked by filter and drain zones. Design and construction of the dams posed multiple challenges, including: 1) variable foundation conditions with occasional unpredictable weak features, 2) use of residual soils derived from rock weathering as core materials, 3) a wet tropical climate with a short dry season, and 4) geologic faults across the dam foundations.

The largest of the dams, Dam 1E, is 2.4 km long and up to 32 m high. The embankment abuts against a small hill at its southern end, and against the original Pedro Miguel Locks at the northern end. Construction of the dam included the following main elements: 1) erection of a 1.3-km-long, 19-m-high, cellular sheetpile cofferdam, 2) installation of a 30-m-long, 18-m-deep, triple-row jet-grout cutoff wall, 3) construction of a 460-m-long, 18-m-deep, cement-bentonite slurry cutoff wall, 4) dewatering and excavation of the dam foundation, 5) treatment and geologic mapping of the foundation, 6) injection of a 2.4-km-long, double-row grout curtain, 7) installation of performance monitoring instrumentation, 8) placement of a 5.3-million-cubicmeter, zoned rockfill embankment, and 9) construction of a 97-m-long, 26-m-deep, secant pile wall to provide closure against the structure of the Pedro Miguel Locks.

This paper provides an overview of the construction of Dam 1E including the sequencing of the works, borrow of the embankment materials from the required channel excavations and other sources, and the key aspects of construction of the above project elements. The paper will also describe the key challenges met and the most important design changes required during construction of the dam.

Standardized Geotechnical Data Management and the Dam Safety Community
Poster Presenter: Raphael Siebenmann, P.E., Geosyntec Consultants
Co-authors: Dr. Ali Ebrahimi, P.E., Senior Engineer; and Dr. Robert Bachus, P.E., Senior Principal, Geosyntec Consultants

Owners of dams and other critical infrastructure assets face many geotechnical data management challenges, from boxes of old paper records, to digital records in proprietary formats, to ever-growing quantities of real-time data instrumentation data. Owners have the responsibility to maintain and archive these records for use on current and future projects, but the burden of upgrading data management systems to efficiently capture, manage, and store this data using an open and non-proprietary format has until now been often insurmountable. 

This presentation will introduce and focus on a new generation of data management and functionality by introducing a standardized geotechnical data management concept referenced as Data Interchange for Geotechnical and Geoenvironmental Specialists (DIGGS). Adoption of DIGGS by the geoprofessional community, including those involved in geotechnical investigation, testing and performance monitoring for dam safety assessments, will facilitate data management, data transfer, and data visualization capabilities. The Geo-Institute of ASCE (G-I)is hoping that dam owners and owners of other critical infrastructure will become an early adopter of DIGGS and that that agencies focused on dam safety will help guide geotechnical innovation over the coming years.

DIGGS was initially developed by a coalition of government agencies, universities, and industry partners whose focus was on the creation and maintenance of an international data transfer standard for geotechnical data required for transportation-related projects. The initial coalition was coordinated by the Federal Highway Administration (FHWA) and completion of the DIGGS standard was awarded to the G-I in October 2013. One important aspect of the interest in DIGGS by the G-I is that the concept of "standardized geotechnical data management"; is not limited to the transportation community. Rather this concept extends to virtually all geotechnical projects and all geotechnical practitioners. 

This presentation demonstrate the application of DIGGS to the dam safety community. It will include a historical perspective, introduction the DIGGS data schema, examples of DIGGS usage for data from geotechnical borings, CPT soundings, laboratory testing, and geotechnical instrumentation. Importantly, the presentation will show how the adoption of such system will result in long-term benefits to the geotechnical profession and other owners of geotechnical assets.

Similarities and Differences in Kingston compared to Tailings Dams and other Ash Ponds.
Presenter: Robert C. Bachus, Ph.D., P.E., D.GE, Senior Principal, Geosyntec Consultants
Workshop: Lessons Learned from Recent Tailing Dam Failures and Path Forward

Description – Recent tailing storage dam and coal combustion residual impoundment failures have cast a negative light on the mining and power generation industries in the US and around the world. Proper design, operation and regulation of these waste facilities is vital to maintain the public safety of the communities they are located in. Understanding the causes of these recent failures and examining lessons learned from previous historic failures is crucial to adequately respond to public safety and environmental impact concerns.

This 2-day workshop include both presentations by experts as well as break-out groups and discussion. Day 1 will provide insight on the Kingston, Mt. Polley and Samarco failures from a technical standpoint, as well as reactions and follow-up measures being implemented by dam safety officials, owners, engineers and other stakeholders. Day 2 will bring together the diverse group of consultants, owners, dam safety and mine safety officials, regulators and other non-government agencies to discuss the changes being implemented in Canada and elsewhere, and proposed changes which should be implemented in the US. Break-out groups will be formed to discuss design changes and regulatory changes which should be considered in response to the failures. New guidelines such as alternative tailing disposal technologies, minimum slopes and other prescriptive regulations, FMEA and other risk-based design approaches and critical controls and governance systems will be discussed during interactive facilitated sessions.

More Information

For more information regarding the event, visit:
For more information on dam safety, contact Dan Schauer at This email address is being protected from spambots. You need JavaScript enabled to view it..
Learn more about Melissa at:
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