Langan Environmental Team on Tour

Our team of expert environmental professionals, headed by Steve Ueland, Managing Principal, is always out and about giving presentations geared towards our industry colleagues. In case you missed any, below is a list of recent presentation topics. For more information or details on upcoming presentations, be sure to stay connected with Langan on Twitter and LinkedIn. For questions, please contact Steve at sueland@langan.com.

Decision Making at Contaminated Sites: Issues and Options in Human Health Risk Assessment
ITRC – National Webinar, 1/28/2015

Environmental Compliance and Self-Auditing: How to Stay Ahead of the Regulatory Curve
South Florida Manufacturer’s Association – Broward College, FL, 1/23/2015

Vapor Intrusion for Lawyers
Webinar, 12/5/2014

NJDEP Data of Known Quality Protocols
Doylestown, PA, 10/25/2014

VI Data Usability – Making Your Case, Maximizing Credibility and Minimizing Exposure
Alpha Analytical’s New Jersey VI Guidance Update – Mount Laurel/Edison, NJ 10/21/2014 and 11/6/2014

Evaluation of the Forensic 1, 1, 1-TCA Ratio Age-Dating Method in Multiple Case Studies
30th Annual International Conference on Soils, Sediments, Water, and Energy – Amherst, MA, 10/21/2014

Source Remediation for TCE Treatment in a Heterogeneous Deposit
Langan Remediation Summit 2014 – Vernon, NJ, 10/14/2014

Geologic Characterization / High Resolution Techniques
Langan Remediation Summit 2014 – Vernon, NJ, 10/14/2014

Transmissivity as a Primary Metric for LNAPL Recovery
International Petroleum Environmental Conference – Houston, Texas, 10/14/20014

Life at Langan: Career Panel
Department of Earth & Environmental Sciences – Lehigh University, 10/9/2014

Techniques, Tools & Tips for Navigating the Ecological Evaluation & Ecological Risk Assessment Process in NJ
New Jersey Society of Women Environmental Professionals – Elmwood Park, NJ, 10/9/2014

Geographic Information Systems (GIS) for Water/Sewer Utility Asset Management
PA American Water Works Association NE District Fall Meeting – Bethlehem, PA, 10/9/2014

Q&A: What were the challenges of the Crescent City Harbor Rehabilitation Project?

Crescent City Inner Harbor

Floating docks and piles were replaced with stronger concrete versions.

A little background information

Four years ago the Crescent City Harbor, named for the crescent shaped beach south of the city, was destroyed by devastating tsunami waves generated from an 8.9 magnitude earthquake in Japan. Langan provided geotechnical engineering services during design, contractor selection, and construction for the rehabilitation of the harbor. The harbor previously consisted of floating docks, which served as slips for commercial and recreational boats, supported by concrete piles with relatively little embedment into the weak bedrock. Most of the concrete piles were sheared off by the forces generated by the tsunami waves. The project included replacing the old piles with piles designed to resist future tsunamis, stabilization of the harbor slopes, and other onshore improvements.

IMG_20130925_104248_554-retouch-LM

New foundations were constructed for the three gangway landings.

Challenges

Langan was a critical part of the project team, working closely with Ben C. Gerwick and Strover Engineering, from 2011 to 2014.  The challenges of this project included designing the facility to resist future tsunamis, shallow highly-fractured bedrock, and high seismicity and potential for strong ground shaking.

Langan’s geotechnical engineering services included developing lateral pile response analyses (L-Pile) to aid in the design of the floating boat docks, providing recommendations and design criteria for the foundations of the gangway landings, and reviewing contractor value engineering, testing, and installation logs. The lateral capacity of the piles included kinematic forces due to a design level tsunami.  In addition to foundation design, we also evaluated the stability of harbor slopes for both static and seismic conditions, and provided recommendations for increasing their stability. We used historical design documents and boring longs, as well as the result of our exploration on land and water.

Crescent City Inner Harbor

A barge-mounted drill rig was used to advance the borings over water.


Today, Crescent City Harbor is completely restored and fully operational. Overall, Langan’s engineering design services were a critical part of assisting the Harbor District in achieving their goal to recreate the harbor better than it was, with the ability to withstand future natural disasters.

 

Answer provided by Haze Rodgers, PE, GE
Haze has over twelve years of professional experience managing, developing, and performing geotechnical studies including explorations, analyses, and construction observation services for various projects throughout California, specializing in offshore design.