Maura Dougherty is joining SCS’s Southwest Business Unit as a Senior Project Manager in the solid waste engineering practice. Dougherty will execute engineering design, operations support, and construction quality assurance projects. She is responsible for project management, client service, business development, technical leadership, and overseeing professional staff teams. Dougherty reports to Vice President and Southwest Business Unit Director of Engineering, Vidhya Viswanathan, P.E., from SCS’s Pleasanton office.
“Maura is a senior professional with proven extensive success in solid waste engineering, construction, and construction quality assurance solutions,” said Viswanathan. “Her experience managing landfill and landfill gas collection and control system engineering and construction projects strengthen our efforts to support our solid waste and recycling clients.”
Dougherty is a registered Professional Engineer in California, Oregon, Washington, and Hawaii. She brings over 20 years of experience overseeing landfill engineering and construction projects, coordinating with regulatory staff, conducting design and technical reviews, and supporting construction work. Dougherty earned her B.S.E. in civil engineering at the University of Princeton and her M.S. in environmental engineering from U.C. Berkeley.
Paul Migwi joined SCS in May 2017 as an Associate Professional in the Overland Park office. Paul graduated from Kansas State University in 2017 earning a Bachelor’s of Science in Civil Engineering with a structural and environmental focus. He is now pursuing his Master’s in Engineering Management at KSU.
Paul was born in Kenya, and at the age of sixteen moved to the United States with his family. As a child, his dream was to become a pilot. When he grew up, he chased his dream and joined the military. Paul chose the United States Air Force because of its Civil Engineering and Pilot programs. In the four years that he served in the Air Force, he learned a lot about teamwork, engineering, and how to achieve his career goals.
After a year in training, Paul was deployed to Afghanistan for six months. After he returned, he worked at different Air Force bases and learned about construction, buildings, and concrete sheet metal. One of his best experiences and most memorable moments was at his first station in Guam where he worked with colleagues to construct a building in the middle of the forest. They used a technique called concrete tilt-up, which is pouring concrete sections horizontally on concrete slabs, and once they are cured, raising, or “tilting”, them with a crane and attaching them on a Pre-Engineering building (PEB). After multiple sections are created and raised, a building is eventually created. When the project was finished, Paul was amazed. Seeing the results of all the hard work he and his colleagues put into a building was a very gratifying feeling. He learned a lot about the technical process, but also about the importance of working as a team. To this day he still remembers just standing there and looking back at the completed building; “it looked awesome,” he said.
Paul’s military experience has helped him in so many ways, especially working well with others. He learned the value of teamwork, and how to work with different personalities. Teamwork has definitely helped him be successful at SCS Engineers. Paul says his favorite part of working at SCS is the people. It doesn’t matter what project he works on, he always enjoys working with his colleagues. They are helpful and supportive and always happy to lend a hand, and they are a big reason why he feels he has been successful at SCS.
Although Paul’s dream to become a pilot led him to join the military, his career goals and ambitions have changed. He enjoyed mathematics and science and wanted to pursue a career where he could use those skills. He majored in Civil Engineering and interned with a construction firm, envisioning a career in construction. Environmental engineering had not crossed his mind until he attended a KSU Career Fair where he interacted with an SCS employee who opened up his eyes to the possibilities. Later that day, Paul did his own research on SCS and was extremely impressed. He loved everything about the company, from what we do, the size of the Overland Park office, and the projects we perform. It also helped that he had friends who had interned with SCS in the past.
His everyday work varies at SCS; he designs using AutoCAD, and his main focus is on solid waste. He prepares Storm Water Pollution Prevention Plans (SWPP), Spill Prevention Control and Countermeasures Plans (SPCC), Facility Response Plans (FRP), and Control Quality Assurance (CQA), among other projects. Paul’s goal is to be out in the field more often. He believes that, in order to become a better designer, he needs to understand how things work in the field.
One of the biggest challenges that Paul has been successful in overcoming is balancing work and life. As a full time student and full time SCSer, it sounds very simple, but time management has made a huge difference in Paul’s life.
One of his greatest achievements and contributions at SCS was working on a permit modification. When one of their sites was at risk of a permit violation, Paul and the team had to redesign a practical and feasible landfill that would be acceptable to the state. When redesigning this landfill, Paul had to keep certain requirements in mind, such as water storage and how it affects the existing infrastructure, elevation, slope, and overall design. This project involved a lot of long days and nights, and, according to Paul, has been the best project he has worked on by far. It helped him see the big picture and truly understand how other projects work.
Paul is very ambitious and goal-driven; he has done a lot in his career and continues to push himself to grow every day. In his free time, he likes to be challenged and enjoys biking on bike trails. His advice to anyone interested in SCS is to, “Jump at the first chance you get; it is an awesome place to work!”
SCS would like to thank Paul and all of the Veterans at SCS for their service. Happy Veteran’s Day to everyone who has served!
CQA is essential for ensuring the proper construction of GCCS and meeting the intent of the design, and can help prevent safety mishaps. Even highly experienced design-build teams invest in expert CQA professionals to protect their capital investment, maintain maximum LFG capture through constructed GCCS, and keep operating and maintenance costs in line. It is critical for CQA person-nel to understand the overall intent of the design drawings, current field conditions, long-term conditions, and strict safety protocols. They must also have the expertise to respond to the questions contractors have during construction, especially regarding modifications to the design which will positively impact safety, long-term performance, and maintenance.
Part 1 of the 3-part article series in MSW Magazine discussed essential elements of the piping system in a landfill gas collection and control system (GCCS). The authors examine landfill GCCS design perspective and the benefits of designing landfill gas (LFG) headers outside of the waste boundary. In Part 2, we focus on construction quality assurance (CQA) services and outline the process of taking the design drawings through completion of the CQA report.
Read Part 2 here. Contains link to Part 1.
SCS Engineers’ Phillip E. Gearing, PE is a winner of the SWANA 2017 Young Professional Award from the Wisconsin Badger Chapter. The Solid Waste Association of North America honors individuals like Phil who make a significant difference in the solid waste industry.
Phil represents the best of the young professionals working within Wisconsin’s solid waste industry. Clients, contractors, and team members appreciate Phil’s leadership and passion for doing the job right.
He is a dedicated father of three children and an avid fan of all things Wisconsin, namely Badger sports, Green Bay Packer football, and Brewer baseball. Wisconsin from head to toe! Phil was raised on a dairy farm in Jackson County near Merrillan and attended the University of Wisconsin – Madison where he earned his B.S. in Geological Engineering, Geology, and Geophysics.
Phil serves clients out of the SCS Engineers office in Madison, WI.
The drainage layers of landfill final covers normally go through a rigorous flow capacity evaluation. This evaluation is necessary to ensure that the volume of water reaching the drainage layer due to percolation of precipitation water through the final cover upper soil layer will not overwhelm the drainage layer in its flow path. If the flow volume in the geocomposite drainage layer is greater than the capacity of the drainage layer, water will exit the geocomposite and enter the overlying soil. The water entering the soil layer can easily saturate the lower portion of the soil layer, which will affect the stability of the slope. The geocomposite should always be designed to have a flow capacity greater than the flow rate of water running through it.
Concave areas of a landfill slope experience flow patterns quite different from slopes that go straight down. Slopes with concaved geometry have an unequal crest and toe lines – the toe line being smaller than the crest line. As a result, the width of the concaved slope decreases as the distance from the crest line increases in the downward direction. The narrowest width of the concaved slope is at the toe of the slope. The drainage layer on the slope experiences the same width change from the crest line to the toe line. This means that the overall width of the channels that carry water within the geocomposite drainage layer decreases toward the toe line, and, therefore, the depth of water in the channels increases. This phenomenon is referred to as flow convergence, and the convergence is toward the vertical centerline of the concaved slope. The flow convergence may be significant enough to increase the water depth in the geocomposite in the vicinity of the vertical centerline of the slope to greater than the thickness of the geocomposite. That, in turn, forces water out of the geocomposite and into the overlying soil, which may result in slope stability problems.
To complement the geocomposite flow capacity along the vertical centerline of the concaved slope in order to accommodate the higher water flow rates in the system, a pipe-gravel-geotextile (a burrito) may be constructed along the vertical centerline of the slope. The burrito, which would be positioned directly over the geocomposite drainage layer, increases the flow capacity of the system at and in the vicinity of the vertical centerline of the concaved slope. The burrito will receive water from the geocomposite where the water depth exceeds the geocomposite thickness. The burrito will be connected to the toe drain system at the toe of the slope, and water in the burrito will be discharged to the toe drain. The water in the toe drain, in turn, leaves the final cover through lateral drain pipes at regular intervals.
It should be noted that not every concaved slope requires a burrito. Some concaved slopes may be fairly wide, and the convergence of water inside the geocomposite may not be significant enough to cause the depth of water to exceed the geocomposite thickness. But, if the concavity of the slope is significant, a severe convergence of water in the geocomposite drainage layer is more likely. In that case, a burrito along the vertical centerline of the concaved slope is highly recommended.
A cautionary construction related note seems to be appropriate at this point. During construction, extra care should be taken to ensure that all geocomposite panels within the boundary of the concaved slope run such that the machine direction of the panels follows a path from the top toward the bottom of the slope. If some geocomposite panels are installed with the machine direction running across the slope width, significant turbulence in the flow will be created at the point where panels running in one direction transition to the panels running in the other direction. The turbulence will reduce the flow capacity of the geocomposite.
If you are planning to install a final cover over a portion of the slope that has concaved geometry and you want your final cover design to properly address flow volumes in the geocomposite drainage layer, please contact us. SCS Engineers has extensive experience with these types of circumstances, and we will gladly review your case and make recommendations. Learn more here.
If you have comments or questions about this article, please contact Dr. Ali Khatami.
Ali Khatami, Ph.D., PE, LEP, CGC, is a Project Director and a Vice President of SCS Engineers. He is also our National Expert for Landfill Design and Construction Quality Assurance. He has nearly 40 years of research and professional experience in mechanical, structural, and civil engineering.
Dr. Khatami has acquired extensive experience and knowledge in the areas of geology, hydrogeology, hydrology, hydraulics, construction methods, material science, construction quality assurance (CQA), and stability of earth systems. Dr. Khatami has applied this experience in the siting of numerous landfills and the remediation of hazardous waste contaminated sites.
Dr. Khatami has been involved in the design and permitting of civil and environmental projects such as surface water management systems, drainage structures, municipal solid waste landfills, hazardous solid waste landfills, low-level radioactive waste landfills, leachate and wastewater conveyance and treatment systems. He is also involved in the design of gas management systems, hazardous waste impoundments, storage tank systems, waste tire processing facilities, composting facilities, material recovery facilities, landfill gas collection and disposal systems, leachate evaporator systems, and liquid impoundment floating covers.
Have you ever found in the sleeve or the pocket of a new shirt the “Inspected By…” piece of paper? You probably don’t think twice about it. You simply look at it and throw it away. However, if you were to think about it, what might the process be to inspect the garment? To be sure the sleeves are the same length, or the collar is sewn on correctly, or that it has all the buttons. That tag is intended to signify that the product was reviewed and has met its required standards to be placed in service.
Ever wonder if anybody reviews the bottom of a landfill? When is it ready to be placed in service?
When I was a kid, a landfill was, for the most part, a hole in the ground filled with trash. Well, we still dig a hole, but since the early 1990’s, municipal solid waste landfills (MSWLF) require a containment system on the bottom and sides of the landfill beneath the waste. These containment systems, i.e. liner systems, are designed to protect human health and the environment by serving as a barrier between the waste and liquid in the landfill from the soil and groundwater outside the landfill. These liner systems are typically constructed of compacted clay liners and geosynthetic materials which are documented and inspected to ensure the liner system was built in accordance with the permit requirements and its overall purpose of protecting the environment.
The landfill liner inspection process is usually called Construction Quality Assurance (CQA) and is an important and integral component of protecting the environment. CQA is generally performed by a third party firm to provide an unbiased evaluation of the liner construction independent of the owner or the contractor.
SCS provides Landfill CQA services across the country. We have proven, experienced field staff that observe, document and test specific physical properties of the soil liner and geosynthetics. Our engineers are experienced and licensed to certify that the liner was built in accordance with the permit requirements.
Landfill CQA is not limited to the liner system. SCS provided CQA for final cover systems, leachate forcemain systems, and methane extraction systems.
If you are wondering more about landfill CQA or have a need for your facility, give us a call. We’d be happy to discuss in more detail and assist with your project. SCS is ready to serve, and help to bring your project in service.
Contact Jeff Reed