Sustainability

Introduction

As the old saying goes, if you don’t have your health, you don’t have anything. At Tetra Tech, we use our Leading with Science® approach every day to support healthy people, healthy communities, and healthy environments. Using the latest technologies and advanced analytics, our technical specialists are helping to make buildings and infrastructure smarter, ecosystems more functional and resilient, and our complex world a little safer, healthier, and more sustainable.

Smarter Buildings for Healthier People

COVID-19 sharpened everyone’s focus on the importance of modern public health facilities. Tetra Tech projects in the United States and Australia illustrate how innovation and technology in infrastructure development can be delivered with speed, ingenuity, and safety.

Gearing up for COVID-19 in New Jersey

When the novel coronavirus began sweeping through New York and New Jersey in March 2020, state and local officials began scrambling to accommodate the anticipated influx of patients. New Jersey Governor Phil Murphy and his public health team worked with the U.S. Army Corps of Engineers (USACE) and the Tetra Tech team to renovate the 250-bed East Orange General Hospital to supplement existing facilities and planned field hospitals.

“We had a team at the site within 12 hours after receiving the notice to proceed,” said Jeff Jones of the Tetra Tech office in Huntsville, Alabama. “Our group included specialized design engineers and construction management professionals from across the company, supplemented by staff from the Cutting Edge Group and Archstone Builders. It was an ‘all hands on deck’ rapid response project, and we went all out to get it done.”

The team designed and installed new patient care rooms, upgrades to water and sanitation systems, emergency power and fire protection systems, and wireless communication networks for the six-story building. Up to 200 people worked in rotating teams 24 hours a day to complete the job.

“This was all happening against the backdrop of a spreading pandemic,” said Steve McGee, Tetra Tech’s project lead. “Before starting work, we had to develop a detailed COVID-19 Infectious Disease and Preparedness Plan. We had dedicated crews on-site to disinfect high-touch surfaces, and personal protective equipment, including masks, was mandatory for all personnel. We instituted social distancing requirements and used infrared thermometers to take the temperatures of people entering the site. Our entire team met the challenges without missing a beat.”

Just weeks after project initiation, the facility opened for patients. The Tetra Tech team worked approximately 25,000 field hours to finish the job.

Award-winning work down under in Victoria

When an average month at this hospital can include 1,400 medical operations, 5,000 educational presentations, more than 100 births, and thousands of other health care services, you’d better be ready. When the Victorian State Government in Australia needed new hospital facilities to serve the needs of a growing population in Bendigo and the Loddon-Mallee region, they turned to a project development group that included Norman Disney & Young, A Tetra Tech Company (NDY), as a key player.

Development of the new $630 million Bendigo Hospital was a massive and complex undertaking. “Our role was integrated throughout the full range of design and construction work,” said Alex Rodger, health sector leader for NDY. “We were engaged as consulting engineers for mechanical, electrical, hydraulic, fire protection, information and communications technology, sustainability, security, specialty lighting, and vertical transportation services.”

The design integrates modern technology and calming green spaces with a highly functional medical center. Notable design elements developed by NDY include a rainwater harvesting system that captures 80 percent of roof runoff for reuse; uninterrupted power source generators for clinical and technical loads; and heat rejection via new adiabatic cooling technologies that save on water and power usage.

Ensuring Safe and Sustainable Water Supplies

Concerns over chemical contaminants in drinking water engage Tetra Tech experts across the spectrum of our water projects, from diagnosing the sources of contamination to designing innovative treatment solutions that protect water supplies.

PFAS analysis and risk management support

The historical use of per- and poly-fluoroalkyl substances (PFAS) that has resulted in groundwater contamination at military bases and other facilities has been in the news in the past few years. PFAS are a group of man-made chemicals used in many consumer goods and manufacturing processes as a surfactant and to create waterproof or stain resistant coatings. PFAS have been used in products like cosmetics, fast food packaging, and in a type of firefighting foam called aqueous film-forming foam (AFFF). Because PFAS are highly soluble, mobile, and resistant to degradation, they often end up in groundwater or surface waters, which leads to a range of human exposure pathways. Bioaccumulation into plants and animals can then create even more pathways to exposure.

Against this backdrop of uncertainty is the need for information—where are the PFAS hotspots? What are the concentrations? How and where are they moving? How do we manage risks to drinking water and other exposures?

Tetra Tech projects in the United States and Australia provide key information that can be used to address those questions. In Ohio, Tetra Tech is supporting Ohio Environmental Protection Agency’s (EPA’s) implementation of a new statewide program to ensure the safety and sustainability of Ohio’s water supplies. A goal of Ohio’s program is to gather data from public water systems to determine if PFAS are present in drinking water.

“Tetra Tech’s Cincinnati office has served as the Ohio EPA’s contractor since 1996,” said Guy Montfort, who is managing the Ohio contract. “We were selected to help implement the statewide PFAS action plan because of our diverse technical capabilities, unique experience with PFAS sampling projects, and capacity for rapidly implementing large-scale environmental projects.”

Tetra Tech is providing technical support to collect more than 4,500 water samples from 1,500 systems, managing laboratory analyses, and reporting data to Ohio EPA on an ongoing basis.

On the other side of the globe, Dr. Sarah Richards of Coffey, A Tetra Tech Company, is helping Australia’s Department of Defence characterize PFAS contamination associated with the historic use of AFFF products at Royal Australian Air Force Bases Darwin and Tindal. Richards focuses on contaminant migration mechanisms, regulatory frameworks, and risk assessment.

“This work requires reviewing historical information, cross-referencing that information with anecdotal information, and then verifying the accuracy using a well-designed sampling regime,” Richards said. “For PFAS, it’s important to remember that the chemicals go where the water goes, and it doesn’t break down readily. Within a catchment, there may be dozens of sources of PFAS contamination from firefighting foams, manufacturing processes, landfills, or wastewater treatment plants.”

To effectively manage such a persistent and widespread chemical, “we need to know the distribution of contamination in the environment and understand how water moves through soil, groundwater, creeks, and drains,” she said. “Developing environmental remediation targets is complex. Data from a robust risk assessment can be used to identify priority exposure pathways, and a good site model can be used to evaluate the relative contributions of different areas of contamination and provide some basis to establish proportionate actions.”

Richards said that mitigation options typically include immobilization or separation. Destruction techniques, such as thermal destruction, plasma, sonolysis (the breakup of material by means of sound, typically ultrasound), and electrochemical oxidation are also evolving. Tetra Tech is supporting research into the development of several innovative approaches to inhibit the spread of PFAS, including enhanced biodegradation for destruction and enhancing the effectiveness of existing techniques for removal of PFAS from waters.

Providing a safe and sustainable drinking water source in Manitoba

The Local Urban District (LUD) of Landmark is a rural community of approximately 1,300 located 25 kilometers southeast of the city of Winnipeg. Several upgrades to Landmark’s central water system were needed to address the presence of metals and insufficient supply volumes—particularly for fire protection.

Landmark and its partners asked Tetra Tech to design a new treatment facility and upgraded distribution system. After extensive investigative, modeling, and other studies of the groundwater, community infrastructure, and present and future finished water needs, Tetra Tech engineers recommended an innovative treatment approach that addressed multiple stakeholder objectives.

Tetra Tech’s solution had to be economically viable and tailored to the unique physical site conditions. Extensive pilot testing of the proposed technology was conducted, coupled with substantial engagement among the design and client teams to select the final design that would be most suited to the funding structure and future improvements.

“The LUD of Landmark Water Treatment Plant project was an exhilarating challenge that pushed our design team to think outside the box and devise new ways to utilize existing innovative treatment technologies,” said Lin Watt, project manager in Tetra Tech’s Winnipeg Office. The project has had a significant positive social, economic, and environment impact on the community, and provides needed infrastructure for future growth and development while improving water and fire safety.”

Tetra Tech’s approach included using biofiltration and activated alumina to remove impurities—, such as iron, manganese, ammonia, and fluoride—from the groundwater. A chemical pre-treatment system was installed to condition the activated alumina system for fluoride removal. Finally, chlorine was added at the back end of the system to provide final disinfection.

Protecting and Restoring the Health of an Ecosystem

Healthy communities encompass not only people, but plants and animals as well. Tetra Tech’s biologists, engineers, and scientists work to restore and protect fragile ecosystems, which provide multiple benefits to humans, such as flood protection, clean water, carbon storage, and sustainable food supplies.

Conserving vital ecological services and sustaining livelihoods in Cambodia

The Prey Lang Extended Landscape, 3.3 million hectares of forested and cultivated watersheds in northeastern Cambodia, provides critical ecological services—fertile soil, carbon storage, and water for more than a million people. Most of the upper watershed forests that serve to regulate and sustain these services have been classified as protected areas and are home to many of Cambodia’s threatened and endangered animal and plant species. Despite the area’s ecological importance, vast diversity, and beauty, it is under severe threat from deforestation, illegal logging, wildlife trafficking, and the impacts of climate change.

To address these threats, the U.S. Agency for International Development contracted Tetra Tech and its partners—the Wildlife Conservation Society and Conservation International—to implement the five-year Greening Prey Lang program. Across three offices, 120 staff are working with the Cambodian Ministry of Environment and other key stakeholders—including local communities, civil society, and the private sector—to implement a suite of technical capacity-building efforts focused on conservation, communities, and governance.

“We strengthen the ability of rangers, in partnership with local communities, to conserve protected areas by collecting and analyzing up-to-date information to monitor environmental health and prevent environmental crimes,” said Chhith Sam Ath, Greening Prey Lang’s deputy director. Forest rangers and community members collect patrolling data, which is uploaded into the Protected Area Management Platform. The online platform combines remote sensing information on forest cover change with field observations to perform advanced analytics that generate monthly patrol plans and identify specific threats, such as land clearing and illegal logging.

Recent Greening Prey Lang Accomplishments

7 protected areas (1.5 million hectares) were strengthened through zoning, demarcation, and adaptive management planning

500 ranger, Community Protected Area, and joint law enforcement patrols were supported

60,000 people’s livelihoods were improved as a result of conservation, ecotourism, and sustainable production interventions

2 million tons of carbon dioxide emissions were avoided through the protection of forests

Reestablishing fish migration in the southeast United States

Since the late 1930s, endangered migratory sturgeon in the Savannah River have been contending with the Savanah Bluff Lock and Dam, located 180 miles upstream of the Atlantic Ocean deep-water port at Savannah. The Savanah Bluff Lock and Dam was built to aid commercial navigation on the river between Georgia and South Carolina. When commercial traffic on the river ended 40 years ago, the facility deteriorated but still served to support recreation and provide a water supply pool for the growing Augusta, Georgia, population.

USACE saw an opportunity to retain the benefits of the impoundment while helping improve passage for fish. As part of the multifaceted harbor deepening/widening mitigation program, USACE staff partnered with Tetra Tech to design a modified impoundment structure that would maintain the elevation of the upstream pool and allow the passage of fish both upstream and downstream.

The Tetra Tech team in Atlanta, Georgia, developed a unique approach for meeting recreational, water supply, and ecological needs. “The design will allow sturgeon access to their historical spawning areas upstream for the first time in 90 years, while providing a pool of water behind the structure for upstream water supply and recreation,” said Brian Watson of Tetra Tech’s Atlanta office.

Tetra Tech engineers recreated natural pools and riffles using rock weir arches, in which the fish can rest on their upstream journey, including a shallow, low-lying floodplain to accommodate seasonal flood waters.

“Our hydraulic design and modeling team worked with the National Oceanic and Atmospheric Administration, the U.S. Fish and Wildlife Service, and USACE to create a fish passage that meets the required minimum depths and maximum velocities for fish movement through the rock weirs,” Brian said. “We used the HEC-RAS 2D model and computational fluid dynamic modeling software to optimize the fish passage crest height, floodplain bench dimensions, fish resting pool dimensions, and rock boulder placement.” When complete, the resulting structure will be the largest rock weir fish passage in the United States.

Tetra Tech

Tetra Tech

Tetra Tech is a leading provider of high-end consulting and engineering services for projects worldwide. With 27,000 associates working together, Tetra Tech provides clear solutions to complex problems in water, environment, sustainable infrastructure, renewable energy, and international development. We are Leading with Science^® to provide sustainable and resilient solutions for our clients. For more information about Tetra Tech, please visit tetratech.com or follow us on LinkedIn and Facebook.

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