Ports

State Pier Infrastructure Improvements

gzadan — Mon, 31 Jan 2022 17:58:31 +0000

State Pier Infrastructure Improvements gzadan Mon, 01/31/2022 - 12:58

Challenge

The $235 million project involves the redevelopment of the State Pier facility in New London, CT. The intent of the project is to address the current shortcomings of the facility and provide a purpose-built facility for heavy cargo staging and deployment, specifically offshore wind components. The existing bulkheads and marine structures are being replaced and the area between the State Pier and Central Vermont Railroad Pier, known as “Central Wharf��, is being filled to provide additional staging area at the port. Filling Central Wharf will require about 400,000 cubic yards of material to be placed though about 40 feet of water and then compacted. The compacted fill must support the heavy loads associated with offshore wind components and other heavy cargo, transport vehicles, and cranes. Due to the presence of very soft organic sediment at the mudline within Central Wharf, long-term settlement, and displacement of the sediment during filling presents challenges to both the design and construction of the project.

Solution

In 2021, GZA worked with Kiewit Infrastructure Co., Construction Manager At-Risk, (CMR) to develop an alternative means of placing and compacting the Central Wharf fill. Originally, the design involved soil-mixing and ground improvement with stone columns. GZA’s innovative method involves a staged approach to filling where the first stage of filling is intended to penetrate and stabilize the soft organic sediment. The second stage of filling is mass fill completed by end-dumping and pushing material from land into the Central Wharf, which is a more efficient way to place this volume of material. GZA also recommended an alternate to the stone column method of compaction. The alternate method uses vibro-compaction of the filled materials. This method does not involve the use of crushed stone, which provided significant cost savings to the project. Construction is on-going and GZA is also providing construction oversight on behalf of Kiewit’s CMR team.

Benefit

GZA’s geotechnical value engineering and marine construction experience, knowledge and experience with multiple ground improvement methods, and extensive work within the offshore wind industry, were integral to reducing the estimated cost of and the successful execution of the construction phase of this project.

Geotechnical services for improvements to the State Pier facility in New London, Connecticut to support heavy-lift port operations including offshore wind component staging and assembly, and other heavy cargo
Provided engineering services to the Construction Manager At-Risk (CMR) for alternate design of placement and compaction of in-water fill between the State Pier and Central Vermont Railroad Pier
Provided pre-bid support to CMR and developed innovative alternate approach to in-the-wet placement and compaction methods
Prepared design submittals for the CMR’s alternate approach
Construction is ongoing and GZA is providing construction oversight of the fill placement and compaction

Energy

Waterfront and Coastal Engineering

Geotechnical Engineering Services

Offshore Wind Advanced Foundation Component Facility, Providence, RI

gzadan — Mon, 31 Jan 2022 17:42:01 +0000

Offshore Wind Advanced Foundation Component Facility, Providence, RI gzadan Mon, 01/31/2022 - 12:42

Challenge

GZA provided geotechnical and environmental services for this design-build project involving the construction of a new building for advanced fabrication and assembly of offshore wind turbine foundation platforms at Berth 6 at the Port of Providence. The building will be used by an offshore wind developer for the assembly and deployment of offshore wind turbine components for one of the large-scale offshore wind farms planned for construction in the mid-2020’s. The original design in the bridging documents included deep pile foundations due to the presence of undocumented fill and soft organic soils within the building footprint. The site is also located next to a former municipal solid waste landfill and methane is present in the soil gas. Methane can accumulate to unsafe levels in open excavations and within enclosed spaces, so mitigation procedures needed to be developed for construction and post-construction conditions.

Solution

GZA completed supplemental subsurface investigations and associated geotechnical and environmental testing. GZA developed an alternate foundation design that utilized rigid inclusion ground improvement in lieu of deep foundations which provided a much more cost-effective and efficient foundation system. The foundation and slab design needed to consider the relatively high floor loads due to the offshore wind components, as well as uplift from the relatively tall but lightweight building. GZA also designed and field-tested a sub-slab methane mitigation system that continuously extracts air from below the slab and monitors indoor air for methane. Construction is on-going and GZA is providing construction-phase inspection and environmental health and safety services for the project.

Benefit

GZA’s local knowledge, geotechnical engineering experience with ground improvement and offshore wind, and environmental experience working with landfill gas were all integral to the successful design and construction of the project when completed in 2022.

Geotechnical services for building to be used for the assembly and deployment of offshore wind turbine components
Completed subsurface explorations and geotechnical and environmental laboratory testing
Designed rigid inclusion ground improvement for foundation and slab support considering loading from offshore wind components
Environmental services included management of contaminated soil, design of a sub-slab venting system, and associated indoor methane monitoring system
Prepared the environmental health and safety plan for the project and performed air and dust monitoring during construction
Geotechnical field inspections and testing during foundation construction

Energy

Geotechnical Engineering Services

Waterfront and Coastal Engineering

Rehabilitation of Davisville Pier No. 2

gzadan — Tue, 31 Aug 2021 16:53:33 +0000

Rehabilitation of Davisville Pier No. 2 gzadan Tue, 08/31/2021 - 12:53

Quonset Development Corporation (QDC) manages and operates the Quonset Business Park, including its two WWII era piers. The facility is a major auto import facility and is looking to provide support for the offshore wind industry in New England.

Challenge

Following the discovery of deficiencies in the cellular cofferdams that define Pier No. 2, and with a desire to increase the berth depth and deck load capacity of the existing structure, improvements were required at the pier.

Solution

GZA was engaged by QDC to perform an emergency evaluation of existing conditions. GZA evaluated pier loading, estimated cofferdam interlock tensions, developed allowable interlock stresses and consulted with QDC regarding pier load restrictions. GZA initially designed and detailed a load transfer platform to provide a local increase in allowable pier live load, thereby allowing for the off-loading of heavy offshore wind equipment at designated areas of the pier. GZA completed a subsurface exploration program consisting of test pits and land and water-based test borings to supplement existing subsurface data. GZA prepared a Geotechnical Data Report (GDR) that was included in RFPs and Construction Document packages associated with the design and construction of a new bulkhead, pier extension, heavy lift platform, and fender system. GZA also completed a drivability study to evaluate pile installation conditions for each of the proposed improvements. Phase 1: GZA was subsequently awarded the first phase of a three-phase program to rehabilitate the pier and extend the east face to add another berth. This phase included the design of a new sheet pile wall and support services during construction. Phase 2: GZA provided geotechnical consultant services during the second phase for a pile supported pier extension. Phase 3: GZA designed and provided construction-phase services for new sheeting on the southern face of the pier.

Benefit

The rehabilitated pier has two deep water berths to service the existing auto import industry and provide the heavy deck load capacity needed to support the offshore wind industry.

Project funded in part with a federal grant
Evaluated existing conditions and the ability to accommodate deeper draft and heavier deck loadings
Performed subsurface exploration program to advise design of future improvements
Pier rehabilitation included accommodation for heavier deck loads and deeper berth drafts
Prepared construction documents for repairs to the east and south faces of the cellular cofferdam pier
Provided bid and construction phase support services for sheet pile replacement of the east and south faces of the pier
Provided geotechnical design guidance for pile supported deck extension on the pier’s east face
Construction phased to maintain operations during construction

Institutional

Waterfront and Coastal Engineering

Davisville Pier No. 1 Repairs

gzadan — Tue, 31 Aug 2021 16:29:22 +0000

Davisville Pier No. 1 Repairs gzadan Tue, 08/31/2021 - 12:29

Quonset Development Corporation (QDC) manages and operates the Quonset Business Park, a 3,160-acre multimodal industrial and commercial business park located on Narragansett Bay. The facility includes two World War II era piers that support major auto import operations.

Challenge

GZA was retained by QDC through a qualification-based selection process to provide engineering services for the rehabilitation of Davisville Pier No. 1. A former Navy Pier constructed in the early 1950s; the pier is currently used for berthing Ro-Ro vehicle transport vessels and as a staging area for the import of passenger cars. The pier is approximately 250 feet wide and 1200 feet long.

Solution

GZA prepared design studies and engineering documents for waterfront repairs and improvements including the following:

Topside and underside surveys of structural elements including caps, deck, beams, mooring hardware, and fender system
Identification and characterization of deficiencies
Selection of repair methods and priorities

GZA also completed a value engineering study to evaluate options for upgrading the current fender system as well as plans, details, specifications, and cost estimates for structural repairs to the concrete deck and pile caps; replacement of deteriorated timber framing; repair and replacement of timber foundation piles; and installation of a new fender system including associated structural improvements.

Benefit

The repairs to the pier structure and the upgraded fendering system more readily accommodated the berthing and the unloading operations for the large auto carriers that regularly call on the port.

Performed condition surveys and subsurface explorations and prepared repair cost estimates
Completed a value engineering study and provided recommendations for fender system upgrades
Prepared construction documents for pier repairs and fender system installation
Provided construction administration services
Repairs were sequenced to maintain operations during construction

Industrial

Waterfront and Coastal Engineering

Bridgeport Boatworks

gzadan — Tue, 05 May 2020 18:55:57 +0000

Bridgeport Boatworks gzadan Tue, 05/05/2020 - 14:55

Challenge

In 2005, the Bridgeport Regional Maritime Complex (BMRC) became a milestone brownfield success story for the State of Connecticut, The Bridgeport Port Authority and the City of Bridgeport by enabling 200 high-wage, ship building jobs on an abandoned 48-acre waterfront site located on Bridgeport Harbor and the Yellow Mill Channel. This project addresses three major concerns for the City of Bridgeport and the Bridgeport Port Authority: restoring industrial land to economic vitality; bringing new, water-dependent industries and high-paying employment opportunities into the City; and creating a home for water-dependent businesses displaced by the nearby Steelpoint Harbor, a proposed mixed-use waterfront development project.

TPA Design Group and GZA worked with the City and the Port Authority assessing the site’s redevelopment potential, identifying potential obstacles to reuse, and recommending an environmental remedial strategy. Steel mills had operated on the BRMC site since the 19th century. The most recent occupant, Carpenter Technology (CarTech), relocated its operations and demolished its local facilities in 1991. Cartech’s departure left a valuable piece of waterfront property unused, contaminated, and littered with building remains and debris. In the late 1990s, as the City pursued mixed-use development opportunities on the nearby site, the Bridgeport Port Authority identified the former Cartech site as a suitable relocation site for water-dependent businesses previously operating on Steel Point. The Port Authority acquired the site; the project received federal financial support from the U.S. Economic Development Administration (EDA) and state funding from the Connecticut Department of Economic and Community Development (DECD) and dedicated staff from Department of Environmental Protection (DEP, now DEEP) to remediate the property and prepare it for new occupants on a priority basis.

TPA retained GZA to address the complex environmental and geotechnical challenges. TPA and GZA worked together on this coastal redevelopment project from the initial property condemnation phase in 2000 through land acquisition to permitting to Remedial Action Plan approval and through the completion of construction of the first phase of the redevelopment, Derecktor Shipyards�� boat assembly building and launching full operations in 2003.

Derecktor Shipyards, a world recognized ship builder was attracted to the property to expand and diversify its shipbuilding and repair operations. A long-term lease for a 23-acre parcel was signed in September 2000. Using the only existing building remaining on the site to allow it to begin operations, Derecktor built and launched four aluminum ferries, and started work on two 235-foot high-speed ferries for the State of Alaska. Derecktor’s operations expanded with the completion of a 45,000-square foot assembly building in 2003.

Redevelopment of the coastal site involved meeting several environmental compliance and engineering challenges. Due to the site’s long history of industrial use, subsurface contamination present including metals and petroleum-contaminated soil and groundwater, and an approximately 50,000 cubic yard release of No. 6 fuel oil.

Key geotechnical issues included the presence of unsuitable soils (i.e., unprepared fill) with expansive slag and existing foundations and other buried obstructions. The property was identified by the Bridgeport Port Authority as key to the future of the water-dependent use of Bridgeport’s waterfront. The property had been vacant for 18 years. Past efforts to redevelop the property had been hindered by concerns over environmental contamination and the ability to control project costs. The Port Authority selected to condemn the property, using environmental remedial cost estimates prepared by GZA. GZA consulted with the Port Authority and their outside legal counsel on environmental matters regarding property acquisition, site design, environmental insurance and regulatory approvals through the construction phase.

The property’s appraised value was reduced by the significant estimated cost for site remediation, resulting in a lawsuit by the former property owner which was settled to avoid prolonged litigation. GZA provided environmental site analysis, development of detailed cost estimates and expert testimony during property condemnation. GZA’s analyses and cost estimates also formed the basis for purchasing environmental insurance to help secure financing for the property redevelopment.

Solution

GZA developed a Remedial Action Plan (RAP) to manage the environmental and engineering challenges during the multiyear build-out of buildings and pavement. The RAP was designed to utilize the proposed site development features to cost-effectively achieve regulatory compliance. GZA gained the approval of the Department of Environmental Protection of the Remedial Action Plan (RAP).

Key RAP features included:

Immobilization of the 50,000 cubic yard plume of separate phase No. 6 fuel oil through the construction of a waterfront bulkhead. The bulkhead was lined with bentonite panels placed above the low water table;
Rendering polluted soils inaccessible to direct human contact with buildings and pavement;
Reuse of about 18,000 cubic yards of dredge spoils to increase site grades above the minimum required flood elevations.
Recording of Environmental Land Use Restrictions.

GZA also designed an innovative approach to foundation construction that eliminated the need for deep foundations and maximized the re-use of on-site soils. TPA and GZA’s integrated engineering efforts were essential to achieving success.

Benefit

RAP recommendations (and regulatory approval for these recommendations) resulted in project savings of approximately $16 to $18 million. The project encompassed a range of site improvements, including removal of abandoned foundations; ground improvements for new buildings; waterfront bulkheads and revetment; dredging in the Yellow Mill Channel to facilitate access; pier construction to support a high-capacity mobile boat hoist; site filling to reduce flood hazard; provision of new utility services; and high-capacity pavements. remediation and paving.

Insights

US Economic Development Administration Grant
Redevelopment of a former steel mill to maritime business park
Accelerated DEEP approvals and construction schedule
Pad design and environmental remedial cap created an estimated $16 -18 million savings in the total cost of construction
2003 Eddy Award-winning project for excellence in economic development
2004 Connecticut Real Estate Exchange Grand Prize Award for excellence in real estate development
2005 American Council of Engineering Companies Connecticut Grand Conceptor Award for engineering excellence.

Connecticut

Water

Buildings & Real Estate Development

Waterfront and Coastal Engineering

Environmental Site Investigation & Remediation

New Bedford Marine Commerce Terminal

Anonymous — Thu, 26 Sep 2019 15:39:50 +0000

New Bedford Marine Commerce Terminal Anonymous Thu, 09/26/2019 - 11:39

Challenge

The New Bedford Marine Commerce Terminal was the first U.S. port facility designed for the offshore wind industry. The $133 million project was completed in 2015 for the Massachusetts Clean Energy Center. The design team consisted of Apex Companies, CLE Engineering, Fuss & O Neil, Aspera Associates, and GZA. The terminal was designed to support the staging, assembly, and deployment of offshore wind components. The terminal consisted of development of 26 acres of land requiring removal of ~18,000 tons of contaminated soil. Construction of ~1,000 feet of quayside, including a new cellular cofferdam bulkhead with a pile supported relieving platform with geotechnically-competent, dense aggregate enabling heavy, uniform, and concentrated loads.

Solution

GZA designed the existing shore and new fill areas for bearing capacity of 4,100 psf for extreme crane loading and concentrated loads up to 20,485 psf or 100 metric tonnes per square meter. Bearing capacity design included overexcavation and compaction of existing fill on-land, and vibrocompaction to improve 5 acres of dredged fill placed through the water. GZA provided real time classification of dredge materials and worked with the Contractor to maximize the beneficial reuse of dredged materials onsite, including reuse of dredged till. GZA was onsite for observing all earthwork, ground improvement, and dredging operations. GZA also performed PDA testing on driven piles for support of the cellular cofferdam deck.

Rock blasting to reach the required dredge elevations was required in close proximity to the New Bedford Hurricane Barrier, an earthen embankment owned by the U.S. Army Corps of Engineers. GZA performed seismic analyses to predict the impact of vibrations from blasting on the Hurricane Barrier. GZA developed limits for blasting weights for the project due to the USACE’s concerns regarding liquefaction and settlement of their structure. GZA presented an approach based on real time monitoring of the Hurricane Barrier to USACE to gain approval for the blasting. GZA installed a remote sensing system to monitor pore pressures and vibrations during blasting. Blasting was approved and completed with no exceedances of threshold values due to GZA’s technical analysis, limitations placed on blasting operations, and monitoring of blasting.

Benefit

GZA’s geotechnical engineering experience and extensive work within the offshore wind industry were integral to the development of this first-of-its-kind U.S. terminal, designed to support the unique needs of offshore wind operations. GZA’s ability to interface with government agencies and protect adjacent sensitive structures during construction was another key to the project’s success.

Insights

Project funded in part with a federal grant
Designed site for bearing capacity of extreme crane loading
Designed a vibrocompaction ground improvement program to densify dredged soils
Monitored 24/7 dredging operations (est. 900,000 cubic yards)
Classified dredge material in real time for re-use on site through visual observation and mobilization of an on-site laboratory
Maximized beneficial on-site use of dredged materials
Performed seismic analysis of proposed blasting to assess impacts on adjacent structures for approval by the US Army Corps of Engineers
Performed PDA testing on driven piles

Massachusetts

Energy

Water

Geotechnical Engineering Services

Waterfront and Coastal Engineering

Block Island Wind Farm, Staging Facility

Anonymous — Thu, 26 Sep 2019 14:04:33 +0000

Block Island Wind Farm, Staging Facility Anonymous Thu, 09/26/2019 - 10:04

Challenge

While staging offshore wind operations for Block Island Wind Farm, the developer was confronted with an aging port facility where the bearing capacity of the facility and condition of the quay was largely unknown. GZA was retained by Deepwater Wind and General Electric to conduct a geotechnical assessment of the facility where proposed staging operations would create larger loadings than previously encountered.

Solution

GZA conducted a geotechnical desktop study of existing geotechnical information and data on the century-old granite seawall to provide bearing capacity recommendations for storage and transport of the wind farm components. GZA also conducted a Phase I Environmental Site Assessment; a subsurface geotechnical investigation to fill data gaps; and a top side, above water, and underwater survey of the seawall. A stability analysis of the seawall used anticipated crane loading for transfer and loadout of the tower segments.

GZA recommended a crane offset of the seawall due to the high crane loading and designed a crane pad. A soil information package evaluated the soil conditions in front of the berth during load out of components for stability of the jack-up vessel used for the loadout. GZA designed the foundations for temporary structures used to assemble and store the tower segments. The tower segments—approximately 90�� tall, 60,000 pounds, and designed for wind loading of over 100 mph—were stored upright and fit with electrical components. The storage frame foundations were designed so that a self-propelled modular transporter (SMPT) could be driven under the frame to transport the tower. GZA’s design calculations and drawings were reviewed and approved by the project Verification Agency, ABS Consulting. During construction of the temporary foundations, GZA provided construction observation and conducted concrete and grout testing.

Benefit

GZA’s geotechnical and environmental assessments and foundation design provided the critical information the developer needed to proceed, confident that the facility was able to accommodate the extreme crane loadings and provide support for construction of the offshore wind farm.

Insights

Geotechnical assessment of port facility for offshore wind storage, assembly, and deployment
Geotechnical desktop study
Environmental Site Assessment
Geotechnical investigation and bearing capacity evaluation of crane loading and component storage
On-land and underwater survey of 100-year-old granite seawall
Stability analysis of crane loading on granite seawall
Foundation design for tower assembly and storage structures

Rhode Island

Energy

Water

Geotechnical Engineering Services

Water Resources

Environmental Site Investigation & Remediation

PSEG Pier and Revetment Evaluations

Anonymous — ��Ϸ��d, 25 Sep 2019 13:53:53 +0000

PSEG Pier and Revetment Evaluations Anonymous ��Ϸ��d, 09/25/2019 - 09:53

Challenge

The PSEG power generation station site was significantly damaged from the unrelenting pounding, over the course of several days, from Superstorm Sandy in 2012. The oil dock, shore-based infrastructure, and the south facing revetments sustained damage from the 100-year design storm surge and wave action. GZA was retained to perform an assessment of coastal and structural damage.

Solution

GZA performed inspections and studies to document the damage and determine the return period of the storm and the wind and wave characteristics. Design plans (30% design level) and estimates of probable cost were prepared for the repair of the oil dock to its original condition and design and construction of the oil dock to meet current code requirements. Based on these scenarios, GZA provided insight into the permitting requirements and code upgrade requirements.

GZA conducted numerous inspections and studies, including: underwater and topside structural inspection of an unloading dock; assessment of riprap and coastal damage; a wind and wave study to determine environmental loadings for “Sandy�� loading; repair scenarios and estimated costs; permitting requirements for repair and replacement of resources; valuated code requirements for reconstruction and replacement.

Benefit

GZA’s assessment of coastal and structural damage to this important power infrastructure included coastal flood modeling to design flood resistant, replacement marine structures.

Insights

Assessment of Coastal and Structural Damage to Infrastructure
Design Plans for Marine Structures
Coastal Flood Modeling for Design for Flood-Resistant Marine Structures

Connecticut

Transportation & Infrastructure

Water

Energy

Waterfront and Coastal Engineering

Natural Hazard Risk Management, Climate Adaptation and Resilience

Former Manufactured Gas Plant (MGP), Site Remediation

Anonymous — Mon, 23 Sep 2019 13:59:53 +0000

Former Manufactured Gas Plant (MGP), Site Remediation Anonymous Mon, 09/23/2019 - 09:59

Challenge

In 2010, when coal tar was detected in the harbor adjacent to a former manufactured gas plant (MGP) site, GZA was retained to analyze the preliminary site investigation data previously collected. The redeveloped site now spans upland and in-water properties owned and operated by several different entities. GZA’s services expanded as client’s needs grew on this complex site.

Solution

Based on the initial data review, GZA developed a Conceptual Site Model that formed the basis for subsequent assessment and remedial actions, followed by design development and construction management and oversight of a multi-season upland, nearshore, and harbor remedy implementation.
The selected remedial alternative included the following elements:

Removal of contaminated soil (source material) adjacent to the harbor, requiring earth support and dismantling and rebuilding historical granite block seawalls
Constructing a vertical concrete and sheet pile barrier to prevent migration of impacted groundwater and NAPL, requiring stabilization/underpinning of walls and structures
Dredging approximately seven acres of contaminated harbor sediments
Placing an armored, active marine cap to treat upwelling porewater
Isolating deep MGP-impacted soil via the construction of an engineered barrier
Automated NAPL recovery from overburden and bedrock

Site-specific challenges considered during remedial design included:

The presence of former MGP infrastructure, including buried seawalls within the upland subsurface and debris within the harbor;
Granite boulders and bedrock, which limited the ability to drive sheets for Support of Excavation (SOE);
The instability of existing granite block seawalls;
Dredging sediments surrounding piles that supported an active, historical marine railroad
An expedited timeline to meet short winter working windows, as established by regulators and local restrictions
Concrete design and QA/QC monitoring of concrete pours for/during freezing marine conditions
Requirements to work multiple shifts, up to 24/7, to meet schedule and work within tidal cycles

Benefit

This technically-challenging assessment and remediation project benefitted from GZA’s expertise in a wide range of environmental, engineering, ecological, and construction management disciplines, resulting in successful integration of the NAPL collection system and integration into the seawall construction.

Insights

Waterfront site in busy commercial harbor spanning multiple properties
Non-aqueous phase liquid (NAPL) in shallow and deep soil, fractured bedrock, and harbor sediments
Hydrocarbons and metals impacts in sediments and pore water
Assessment and preparation of comprehensive site assessment and risk characterization report
Remedial design and preparation of Remedial Action Plan, Remedy Implementation Plan, bid specifications and drawings, and Final Inspection Report
Construction management for final remedy that included mechanical and suction dredging across 7 acres, management of 30,000 CY of contaminated sediment; water treatment; stabilization/removal/reconstruction of pile-supported piers and seawalls including concrete pile jacketing; installation of sheet pile DNAPL cutoff wall and impermeable concrete vertical barrier; marine capping; and NAPL extraction from overburden and bedrock

Massachusetts

Water

Institutional

Transportation & Infrastructure

Energy

Geotechnical Engineering Services

Environmental Site Investigation & Remediation

EHS Regulatory Compliance

Land Use and Environmental Planning

Natural Resources and Ecological Services

Waterfront and Coastal Engineering

Construction Management

Manufactured Gas Plant (MGP) Remediation