Infrastructure Week (May 16–23) is a national week of events, media coverage, education, and advocacy efforts to bring the state of the nation’s infrastructure to the attention of all Americans. Forester Media, the publisher of MSW Management magazine, is an Infrastructure Week affiliate. John Trotti, MSW Managing Editor recently surveyed Jim Walsh, P.E., BCEE, President and CEO of SCS Engineers and long-time friend of the magazine on the topic. Jim is first out of the blocks to answer the four questions John asked of respondents from MSW and Forester’s other publications, Business Energy, Erosion Control, Grading & Excavation Contractor, Stormwater, and Water Efficiency.
MSW Management (MSW): Which infrastructure projects should be given priority? Roads and bridges? Dams and levees? Water supply? Electrical grid? Waste management?
James Walsh (JW): Typically public safety, cost, and benefit determine the priority for infrastructure projects, and different political jurisdictions have different priorities. Where highways and bridges are new but waste management facilities are old, the priority might be waste management facilities, and vice-versa. Some types of infrastructure are more amenable to private sector solutions, which can allow the government to focus on other types of infrastructure. The trend in waste management, for example, has been to rely on the private sector in the last decade
Each segment faces difficult challenges; the most significant is funding. Waste management does not necessarily have priority over other projects, but has progressed by regionally identifying the infrastructure necessary. Thus, each region avoids the pitfalls of competing for funding with other regions and other projects.
SCS Engineers focuses on waste management, but there are opportunities to interact with other segments in sustainable ways. For instance, we have energy clients who supply coal ash to specialty cement companies who use it to make “green” cements that last longer in applications such as road construction. We design and construct facilities that take the byproduct gases from the decomposition in landfills to generate electricity reducing their dependence on fossil fuels, or directly use the gas for energy to power wastewater plants simultaneously cleaning and conserving water. We find ways to safely redevelop contaminated property supported by existing infrastructure, thus reducing the need to build new infrastructure.
In short, we work toward helping clients find sustainable solutions to infrastructure projects.
MSW: Is there a solution to long-term infrastructure funding?
JW: With respect to the waste management infrastructure, waste systems require significant capital investment in land, equipment, facilities, and infrastructure. While many governments have decided to rely on private industry instead of financing new governmental facilities, others have become much more sophisticated in adopting private sector approaches to financing. Pro-Forma Economic Life-Cycle Models can assist governmental entities to identify the critical variables that can impact the success of an infrastructure project. Moreover, economic models evaluate how various components of a waste system and variable assumptions integrate together into a sensible approach. Pro Forma Economic Models allow for a careful analysis of the life-cycle costs and potential revenue sources and identify factors that will influence the waste system costs and demonstrate how to adequately and equitably fund the system. These Models provide different scenarios and eliminate options that are not financially feasible or do not fit a region’s short- and long-term needs or priorities. Sensitivity analysis can be conducted to understand better the impact these variables have on capital costs, operating expense, and the overall system economics. By assessing the economic and regional benefits first, we can focus on designing and building infrastructure solutions that are safer, longer lasting, and affordable. Other benefits include adjusting the Model if there is a major change in the commodity market, such as plastics’ recycling is experiencing now and when considering the use of new technologies.
Every industry segment and every region have a different blend of socio-political conditions, geography, and monetary resources—we assess and design to their particular needs. Adopting new waste management technologies, such as anaerobic digestion or waste diversion, as part of an overall waste management program can be integrated into the Model to study how, and if, they sensibly integrate within the existing program. New technologies are typically more expensive than mature technologies such as recycling facilities and landfills, but that condition alone is not why they are considered valuable to a region. The framework considers elements key to integrating anaerobic digestion for example into a long-term program. Capital investment, a significant centralized source of high-quality organic waste, power costs and economic utility incentives, limited land suitable for composting, lack of conventional waste-to-energy facilities, or a ban on organics disposal in landfills are some of the considerations.
Many states are developing organics diversion initiatives, discouraging or banning organics from landfills; they will want to develop separate capacity for diversion within their overall program to build a sustainable plan for the long-term. In some states there is plenty of environmentally sound landfill capacity, recycling facilities have adequate capacity, and the socio-political climate has different ideals. What works in Iowa might not be suitable for California.
MSW: What kind of harm is the current state of our infrastructure doing to the economy and the community?
JW: Every four years, the American Society of Civil Engineers releases a “Report Card for America’s Infrastructure” depicting our nation’s infrastructure condition and performance. In a traditional school report card format, individual infrastructure segments are assigned letter grades—solid waste has the highest grade of B- in the most recent report published in 2013. The waste management infrastructure in the United States is robust, diverse, and significantly supports our economy and communities by providing safe and cost-effective management of the materials that we discard on a daily basis.
MSW: What can various government entities—from local to Federal—do to attract private sector support and investment?
JW: In the United States, private solid waste facilities manage 75% of the municipal wastestream. The waste management industry has many examples of public/private partnerships and significant investment by the private sector. Just look at firms like Waste Management Inc., Republic Services Inc., Waste Industries, Waste Connections, WCA Waste Corporation, Covanta, and Wheelabrator, which own and operate numerous landfills, compost facilities, waste-to-energy facilities, transfer stations, processing facilities, alternative technologies, and hauling companies. These facilities require significant private investment. Allowing private industry to participate in the management of waste management infrastructure brings needed fiscal discipline and accountability to the overall waste system infrastructure.
The private sector is attracted to markets that are predictable and that provide an appropriate return on investment. Jurisdictions with a reputation for making sudden unpredicted changes in regulations that adversely affect the return on investment will find it difficult or impossible to attract private sector support.
The waste management sector and SCS Engineers have seen our share of magic technologies that are literally too-good-to-be-true, yet somehow attract governmental support both financial and otherwise. It is fine for government agencies to provide grant support for research related to promising new technologies, but adopting an unproven technology as the sole means of waste management is inviting a public health crisis. Private sector investment is not attracted to jurisdictions that have unrealistic expectations.
About James Walsh, PE, BCEE, President and CEO of SCS Engineers
Jim has worked at the forefront of sustainable waste management for more than 40 years. He has authored numerous publications, technical support documents, presentations for the USEPA, US DOE, the Gas Research Institute while serving the Solid Waste Association of North America (SWANA), National Waste and Recycling Association (NWRA), and the Environmental Research and Education Foundation (EREF), among others.
Taken as a whole, mixed MRFs have operated well since their reincarnation in the early 1990s and continued refinement through today. The sorting technology, which has been evolving for the last 25 years, has been proven to work and is reliable. Complete, pre-engineered integrated systems have been available now for years from a growing selection of established companies dedicated to the solid waste industry that can provide planning, engineering, manufacturing, controls, and startup, whether for new facilities, or retrofits of existing older facilities.
With that said, the following conclusions are offered for consideration:
Contact the authors: Bruce Clark and Marc Rogoff
Dr. Dale W. Daniel, an Associate Professional with SCS’s Oklahoma City office, recently published a summary article of his dissertation research through the U.S. Department of Agriculture’s Conservation Effects Assessment Project. The primary goal of the research was to provide under-standing of the potential climate mitigation services provided through wetland conservation and restoration in the High Plains region of the United States. Focus was placed on greenhouse gas (GHG) emissions from wetlands and adjacent upland landscapes as well as identifying some of the drivers of GHG flux that are influenced by various land management practices. The project also sought to understand how sediment removal from wetland basins influenced Carbon and Nitrogen content as well as Carbon sequestration services.
In 2007, the Society for Ecological Restoration International (SER) stated that global climate change is a real and immediate threat that requires action, and ecological restoration is one of the many tools that can help mitigate that change (SER 2007). However, recent debate within the conservation science community has arisen concerning whether restoring ecosystems for C offset projects may shift focus away from other important benefits to society (Emmett-Mattox et al. 2010). Indeed, not all ecosystem restorations make viable ecological offset projects for industries seeking to reduce their C emissions, and those that do, may not always occur in areas where restoration funding is needed the most. This study demonstrated that management practices focused on restoring natural landscape functions, including native species plantings and basin sediment removal, can increase climate mitigation services provided by wetland and upland ecosystems within a region heavily impacted by land use change.
By Ali Khatami, Ph.D, P.E., SCS Engineers National Expert
Leachate seeping out of a landfill slope can be a major issue during the active life of a landfill, and waste operators undertake significant efforts to control and manage it. Uncontrolled seeps can cause soil erosion on the slope, odor issues, and unpleasant scenery on the landfill slope which is visible to adjacent public roads or properties. Leachate can also travel beyond the liner boundaries into perimeter ditches.
Leachate also can seep below the final cover, and that causes a different set of problems. Leachate seeps below final landfill covers are rarely discussed because of the general consensus that they become inactive after construction of the final cover system. That may be true under certain conditions, but very often, leachate seeps remain active as long as the source of water remains active and continues discharging through the seep locations. Leachate seeps below final covers can potentially:
If the final cover geomembrane is not welded to the bottom liner geomembrane, leachate seeping to the toe of the slope can reach the landfill perimeter ditch and contaminate the surface water, or it can percolate into the ground and cause ground water contamination that may be detected in nearby groundwater monitoring wells. Leachate seep also may enter the perimeter berm structure and saturate the berm to the point that the stability of the landfill slope becomes a concern.
If the final cover geomembrane is welded to the bottom liner geomembrane, the only way to address the accumulation of leachate under the cover at the toe of the slope is to open the geomembrane, remove the leachate, and close the geomembrane again. However, this process does not solve the seep problem, which will continue to recur.
SCS has designed various leachate toe drain systems to collect and dispose of leachate that flows below the final cover geomembrane. Leachate toe drains have become a standard feature in the final cover designs for some of our clients who have experienced the benefits of the system.
If you have leachate seep issues at your landfill, please contact SCS. We can develop a design specific to your landfill and the conditions at your facility. We also provide construction recommendations and a preliminary cost estimate for implementation of the system. SCS has extensive experience with the permitting of these systems; we prepare modification applications for permitting purposes and obtain approval from the state regulatory agency. SCS can also prepare the construction plans. We also offer design-build options, employing our SCS Field Services Construction group to construct the system, which often can be a cost-effective way to implement your system.
Questions? Contact Ali Khatami, PhD, 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.
Long story short, an escapee from San Quentin and any uncontrolled methane air molecule may be more similar than we may presume. In fact, a common LDAR practice is to use an infrared imaging camera; similar to the camera often used in search of fugitive criminals.
On a serious note, fugitive emissions are something that both industry and regulators have been focused on for decades, and the past and present efforts made to limit them are no less than remarkable.
Specific to Onshore Oil and Gas Exploration & Production, the Federal Regulations applicable to fugitive emissions are fairly young. Finalized in 2012, NSPS OOOO is no longer a toddler and is in the middle of growing into NSPS OOOOa (Public Comment Deadline March 11, 2016). On a national scale, NSPS OOOOa will expand fugitive emission monitoring and control requirements (VOC’s and methane) to several facility types associated with the industry and is expected to be finalized before the close of 2016.
In California, fugitive emissions from Onshore Oil and Gas Exploration & Production have been regulated for a long time. In fact, the O&G industry in Santa Barbara County has dealt with fugitive emission requirements since 1979. Since then SCS Engineers has been assisting with fugitive emission monitoring for our valued clients. Today, SCS Engineers provides the Oil and Gas Exploration and Production industry with efficient and effective LDAR services.
So fear not, SCS Engineers is ready to supply the knowledge and skill set you need to stay compliant, maintain your operations, and respect your bottom line. Remember, unless the doors are closed, pumps are turned off, and equipment is flushed and plugged; fugitive emissions requirements and LDAR will likely still apply.
Applicability: Determining Federal vs. State oversight is the first step. Non-Major Source Oil and Gas Production facilities are either subject to NSPS OOOO (soon to be OOOOa) or a related State specific rule (i.e. Colorado Regulation 7). Once oversight is determined, then there may still be exemptions for your facility (i.e. facility constructed before August 23, 2011). And finally, once regulatory oversight is confirmed and you determine that LDAR is required for your facility, then the last step is to figure out which equipment is applicable (i.e. VOC content > 10% by weight). Basically, an applicability determination can be daunting.
Equipment: EPA’s Method 21 is historically and currently referenced in all LDAR regulations. Method 21 requires an instrument such as the Flame Ionization Detector (FID) or Photo Ionization Detector (PID). More recently the Optical Gas Imaging (OGI) Camera has been included in LDAR regulations and utilized in LDAR programs. Presently, there are several instrument technologies that exist and are in the works, but not yet mainstream in Oil and Gas sector. Ultimately, if you were to find yourself conducting LDAR monitoring at your oil and gas facility tomorrow per an established regulation, you would most likely need to use an FID or OGI.
Recordkeeping: Personally, I like the simplicity of using paper forms for field notes; however, the old-fashioned way comes with risk. The up-front and ongoing data involved with an LDAR program is too much for maintaining a paper to computer process, regardless of how organized you think you are. Therefore, a computer database platform is recommended and necessary for managing your LDAR recordkeeping. Beyond just recordkeeping, a database platform can organize schedules, alerts, generate reports, extract trends, and many other applications to help keep your LDAR program compliant. One such platform worth considering is SCSeTools™. This cloud-based software can provide the database capabilities used on the desktop, but almost more importantly, provides mobile data input capabilities with the SCS MobileTools™ application fit for Android and IOS systems. Keep the fugitives from escaping, and document containment for the authorities!
About Lucas Marsalek: Lucas has been an Environmental Consultant for over 8 years; he applies his expertise as a leader for oil and gas production environmental and regulatory compliance projects. Marsalek has a B.S. in Forestry and Natural Resource Management from California Polytechnic State University, San Luis Obispo, CA.
Whether you want to discuss LDAR or Dodger baseball, don’t hesitate to contact me, or SCS Engineers.
Resources:
Learn more on the SCS service pages and read SCS project case studies from across the nation to help fine tune your program.
Outside links to the EPA proposed rulemaking website:
This workshop was insightful, tightly constructed, and – most impressive – able to deliver high quality information that businesses can use immediately. I have been to hundreds of business workshops where companies feel drowned in the amount of expert information coming at them. Not so at this concise, one-hour workshop where businesses clearly understood the next steps they should take and where they can find resources to help them proceed.
Jo Marie Diamond, President and CEO, East County Economic Development Authority after attending the SCS seminar in San Diego, CA. on March 1, 2016.
SCS Engineers staff professionals are available to answer questions about compliance and the proposed fee schedule changes for attendees and any business unsure about the storm water permit. We can help clarify questions such as:
See the slide presentation here if you have not attended the seminars.
If you have questions about how the storm water permit could impact your business, or would like to know more about the permit fees, please contact Cory Jones, your nearest SCS office in California, or .
Cory Jones, P.E., ToR, QSIP, is a stormwater program manager at SCS Engineers. Jones manages complex projects for private and public clients that include site/civil, water/wastewater and stormwater engineering. He has completed a wide variety of special studies in storm water management and National Pollutant Discharge Elimination System (NPDES) compliance for federal, state and municipal public agencies.
The benefits of implementing these cleaning recommendations for leachate collection pipes will help keep the pipes clean and fully functioning; helping landfill operators prevent the potentially serious complications of clogged pipes and immovable leachate.
By Dr. Ali Khatami, P.E., SCS Engineers
Some states require that leachate collection pipes be cleaned with high-pressure jets on a regular basis (for example, every ten years or even more frequently); however, the rules don’t clarify or set forth the specific conditions under which the jet cleaning should be performed. Some landfills have undertaken jet cleaning while the pipes are partially or fully submerged in leachate above the liner. Unfortunately, jetting under water may drastically reduce the effectiveness of the pressurized jet, resulting in a pipe that is not cleaned properly. This is even more important when the jetting is intended to remove biological growth on the pipe walls and in the perforation openings.
In addition, many states do not require videotaping the pipe after jetting. Videotaping is the best way to verify that the pipe was cleaned successfully. If the leachate collection pipes are not properly cleaned, then over a period of 20 years or so, they can be adversely impacted by severe biological growth and buildup in the pipe perforations to the point that liquid can no longer enter the pipe.
Another shortcoming is that the rules do not specifically require that the riser pipes (where the submersible pumps are located) be cleaned or videotaped. Therefore, due to the added costs, some landfill operators may not clean the riser pipes as part of the required cleaning events, or they may delay such cleanings for an extended period. This can prevent leachate from flowing into the riser with the direct and serious consequence that leachate cannot be removed from the sump.
Another issue to consider is that pressurized jet cleaning procedures do not necessarily push the solids that separate from the pipe wall out of the pipe inlet opening through which the cleaning nozzle entered the pipe. As a result, these solids flow out of the pipe and into the gravel bedding on the outside of the pipe, and can potentially clog the void within the gravel pack around the pipe or in the sump. Clogging the sump gravel can mean reduced flow capacity from the leachate collection pipe to the riser pipe and the submersible pumps.
To resolve these issues, SCS recommends the following:
The benefits of implementing these recommendations will help keep the pipes clean and fully functioning. These suggestions help prevent potentially serious complications that the landfill operator may have to address if the pipes are clogged and leachate cannot be removed.
Questions? Contact Ali Khatami, PhD, 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.
Thirty-four senators and 171 representatives argue in a brief filed February 23, that the EPA overstepped its boundaries in creating the carbon-cutting Clean Power Plan. In short, the brief states that they feel that Congress never gave the EPA a clear statutory directive or authority to transform the nation’s electricity sector. The brief points out that the EPA seeks to make “decisions of vast economic and political significance” under a “long-extant statute,” and in doing so must point to a “clear statement from Congress.”
Yesterday’s brief comes just two weeks after the U.S. Supreme Court ruled the EPA cannot begin enforcing the rule until legal challenges filed by 25 states and four state agencies are resolved.
The D.C. Circuit Court of Appeals will hear oral arguments on the merits of the states’ case on June 2.
With the brief it is clear that the Clean Power Plan is not only facing legal challenges but also political ones. It may be left for the next Administration to pick up this pieces and decide the fate of the Plan.
One general problem that is encountered in traditional designs is the potential for clogging of geotextiles in the vicinity of the leachate collection pipes.
Traditionally, leachate collection pipes are encased in gravel, wrapped in geotextile, and positioned above the leachate collection system geocomposite drainage layer inside a trench or at the trough of the bottom of a cell. In a traditional design, leachate travels through the geonet component of the geocomposite and reaches the leachate trench where the leachate collection pipe is located. Here, leachate must flow out of the geocomposite, through the upper geotextile component, and then through the geotextile wrapped around the gravel, before entering the gravel and eventually flowing through the pipe. The flow through the geotextiles is concentrated in small areas on the two sides of the leachate collection pipe-gravel-geotextile wrap. Considering the large volume of leachate that follows this path over the life of the cell, it is evident why traditional designs are doomed to clog.
The clogging impedes the free flow of leachate from the geocomposite drainage layer to the leachate collection pipe. As the clogging occurs, the leachate must find a new flow path (most likely further back from the collection pipe), and flow out of the geocomposite, through the geotextile wrap at a different location, and eventually enter the gravel and pipe. This new location will eventually clog as well for the same reasons that the initial location was clogged. This process continues until the geotextile within the leachate trench becomes completely clogged and the system loses functionality. Unfortunately, the periodic cleaning of leachate collection pipes (usually every few years) cannot address this issue because the problem is outside the pipe and the high-pressure jets inside the pipes do not reach the clogged locations.
The solution is to eliminate geotextiles from the flow path of the leachate, extending from the geocomposite drainage layer to the leachate collection pipe. Over the past several years, SCS has successfully designed and constructed numerous landfill cells with no geotextile in the flow path of leachate from the geocomposite drainage layer to the leachate collection pipe. The design follows the “Rule of Transmissivities” which dictates that a proper design should provide the free flow of leachate from one medium to another and that only occurs when the transmissivity of the latter medium is equal to or greater than the transmissivity of the former medium. If a design does not satisfy the Rule of Transmissivities, there may be potential for clogging, bottlenecking of flow, and other consequences resulting from impeded flow in the system.
SCS Engineers is a leader in the design of landfill lining systems, and we have experience with issues that may not be familiar to other firms. If you are interested in the design of a leachate collection system at your facility, please contact SCS. Our professional engineers will gladly review your design and make recommendations if needed. We can identify potential issues and improve designs to prevent future problems and maintenance during the life of your facility.
Questions? Contact Ali Khatami, PhD, 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.
Read more here. Rule of Transmissivities at Material Interfaces in Landfill Leachate Collection Systems, in Talking Trash
Pressure testing of HDPE pipes takes place at almost every landfill lining system and landfill gas collection system construction project. The pipes must be tested to make sure the fusion welds are intact and are not leaking. When engineers specify pressure testing, they identify the required test pressure, the duration of the test, and the allowable pressure drop at the completion of the test. The test pressure may vary from one pipe application to another. For example, the specified test pressure may be as high as 1.5 to 2 times the maximum service pressure in the pipe for leachate forcemain pipes; whereas for pipes used in landfill gas collection systems, where the pipes are under vacuum, the specified test pressure may be less. Test duration may vary from one hour to a few hours, and the allowable pressure drop may vary from zero to a percentage of the initial pressure.
What is often missing from pressure test specifications is the effect of the ambient temperature variation on the pressure changes within the pipe during the test. If incompressible fluid (e.g., water) is used for pressure testing, pressure changes due to ambient temperature variations are less significant than when compressible fluid (e.g., air) is used.
For incompressible fluids, SCS has developed a mathematical model that enables the engineer or contractor to calculate pressure changes due to ambient temperature variations during the test. The calculated pressure change should be considered when evaluating whether the test results are passing or failing. Increasing ambient temperatures during the test may cause expansion in the pipe, and the expansion causes an additional pressure drop that is not caused by any leak in the welds. On the other hand, decreasing ambient temperatures may cause contraction in the pipe, which increases pressure in the pipe. In this case, a pressure drop due a leak in the weld may not be detected because of a higher pressure created inside the pipe due to pipe contraction. It is recommended that engineers or contractors use the mathematical model to calculate a modified allowable pressure drop by considering the calculated pressure change (positive for pipe expansion or negative for pipe contraction) before the pass/fail assessment is carried out.
Recently during the test period in the field, a pressure drop was experienced that slightly exceeded the specified allowable pressure drop. Field staff reported ambient temperature variation during the two-hour test. When the modified allowable pressure drop was calculated using SCS’s model to account for the ambient temperature variation, the test ended up passing. Note that field documentation is extremely important for assessing the pass/fail results. This becomes even more important when the specified test duration is several hours long and the ambient temperature variation is significant.
Questions? Contact Ali Khatami, PhD, 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.
Read more here. Pass/Fail Criterion for HDPE Pipe Pressure Testing Using Incompressible Fluid, in Talking Trash, March 2015