On a per ton basis, our emission rate has declined every year since 2010. In 2017, our greenhouse gas emission rate was 116 kilograms of carbon dioxide equivalents per ton of waste and recyclables received. This is a 20% reduction since our last report, which means we have achieved our goal of continuous improvement.
We attribute our success to our investment in landfill capping and landfill gas collection infrastructure, as well as select fuel and energy efficiency projects. Still, we see opportunities to improve in the areas of landfill gas recovery, fleet fuel efficiency, and facility energy efficiency, as detailed below
Since 2005, our focus on landfill gas collection has prevented millions of metric tons of greenhouse gas emissions. Much of this gas was diverted to landfill gas to energy facilities to produce renewable electricity, thus yielding a second greenhouse gas benefit.
Still, landfill gas continues to account for 87% of our overall carbon footprint. We believe that we can further enhance the gas capture performance at our landfills. We will do so with a renewed focus on well-tuning and continued strategic investments in landfill gas infrastructure.
Our fleet is the second largest contributor to our overall carbon footprint, accounting for 11% of our total emissions. Other emissions from our fleet, as with any heavy-duty vehicles, include particulate matter and NOx, which impact local air quality.
As discussed earlier in this report, we are improving the emissions performance of our vehicles through our 5-year fleet plan, which is systematically increasing the number and percentage of new (model year 2007 or later) vehicles within our fleet. Because these newer vehicles have better emission controls, our fleet is getting cleaner with each passing year.
We will achieve further improvements through a continued focus on integrating alternative fuel vehicles into our fleet, provided that they must meet our standards for reliability and performance. We will also continue to pursue routing efficiency opportunities to reduce our fuel consumption while improving our productivity.
Heavy-duty trucks and equipment rely on liquids like fuel, lubricants, and coolant to operate. To protect our local water resources, we need to properly manage the storage and distribution of these liquids, prevent spills, and respond rapidly when spills do happen. Each of our maintenance shops has best management practices and infrastructure for properly handling liquids, and relevant employees are trained in spill prevention and response. Our equipment preventive maintenance programs help to minimize the potential for spills by identifying and correcting worn or damaged components on a proactive basis. When accidents do happen, our staff are trained to respond quickly to contain, clean up, and report the spill. In 2017, we had 93 reportable spills, including 25 that occurred at our facilities, and 68 that occurred off-site. Each spill was properly reported, contained and remediated, and documented with appropriate corrective actions. The majority of the reportable spills consisted of small hydraulic fluid or lubricant releases contained to the immediate spill area, and no spills to surface water or wetlands occurred.
Stormwater is the rain and snowmelt that flows over the surface of the land. To protect local water resources around our facilities, we need to ensure that this water doesn’t pick up and carry contaminants or excess sediments off-site. We deploy best management practices to keep runoff clean and prevent erosion. To track performance, we regularly monitor and sample our outfalls and report the results to regulators as required by our stormwater permits.
Each of our active MSW landfills is equipped with a highly-engineered double composite liner system designed to contain and collect the liquid – called leachate – that percolates through the waste. These liner systems contain both primary and secondary monitoring systems, so we can be sure they’re working properly. In 2017, we collected over 100 million gallons of landfill leachate and delivered it to permitted wastewater facilities for treatment. To protect the quality of our leachate, we have special waste approval processes and waste screening practices to ensure that our facilities accept only the waste materials they were engineered to manage.
Litter on the land can have the potential to be transported by wind or stormwater to water bodies, so we see litter control as a form of water protection. At each of our facilities, collecting windblown litter is a part of daily operations. Our landfills use redundant litter control systems including portable litter fences, permanent perimeter net systems, and manual collection efforts to control wind-blown debris. Our collection drivers do their best to minimize windblown litter as they collect waste and recyclables. One program that has had litter prevention benefits is the transition from open recycling bins to wheeled recycling carts with lids.
Odor management is a complex science that draws on the fields of meteorology, physics, biology, chemistry, and more. At our landfills, we identify two broad classes of odors: those related to arriving waste and those related to waste-in-place that is breaking down. To control the latter form of odors, we rely on the same landfill gas collection systems that we use to cut our carbon footprint and produce renewable energy (as discussed in the preceding pages). To manage odors from incoming waste, we deploy daily cover systems and misting technologies that capture and contain odiferous compounds. Where possible, we also work with customers to pre-treat their waste in ways that mitigate odors at the source, so they are stable upon arrival at our facilities.
To operate our facilities, we maintain hundreds of permits and certifications, and are held accountable for thousands of permit conditions and requirements encompassing everything from major environmental protections to relatively minor labeling and administrative reporting requirements. To ensure ongoing compliance, our facility managers and operators receive support from our safety, environmental compliance, and engineering specialists. These specialists conduct internal audits and permit reviews, maintain databases of permit conditions and deadlines, develop training programs, and communicate with external regulators to keep abreast of evolving rules and requirements. The team also works to ensure rapid corrective response in the event that incidents do occur. Each year, we evaluate the environmental compliance incidents that occurred during the previous twelve months and implement corrective actions to prevent reoccurrence. Our corrective actions can include the construction or installation of new engineering controls, retraining of company staff, the assignment of additional internal or external technical resources, or improvements to our reporting and information-sharing practices. Still, we strive for continuous improvement and our goal each day, month, and year is to achieve a perfect record of zero environmental compliance incidents.
Efficient Heating and Cooling: To keep our servers at optimal temperatures, we are constantly removing heat from our server room. Rather than letting that heat go to waste, we now capture it and use it to heat our offices. By installing water-sourced row coolers in our server room, installing and optimizing heat pumps, upgrading our inefficient cooling tower, and re-piping our boiler, we're keeping our offices comfortable while reducing our use of propane and electricity.
Energy Management System (EMS): Our new EMS gives us unprecendented visibility and control over our lighting, heating, and cooling. This enables us to make ongoing adjustments to optimize both emplyoee comfort and energy efficiency.
LED Smart Lighting Upgrades: Our home office (along with our neighboring recycling facility and administrative buildings) underwent lighting upgrades which have yielded significant efficiencies. By installing efficient LED smart lights, we cut our overall wattage, optimized lighting levels, and enabled sensors and dimmers that automatically adjust the lights when no one is around, or when ambient lighting changes.
We expect these improvements to help cut our electricity, propane, and water consumption. As we close in on the one-year mark of having completed the retrofits, we will soon be able to calculate and report the precise savings and benefits. We thank Efficiency Vermont for their support.
Emerging contaminants can be found in common household and commercial products such as detergents, fragrances, medications, disinfectants, stain repellants, water-proof coatings, and more. Given their prevalence in so many consumer products, these constituents also appear in our waste streams.
The most recent emerging contaminant with relevance to disposal streams is a group of man-made chemicals called Per- and Polyfluoroalkyl Substances (PFAS), which have been manufactured and used around the world since the 1940s. They can be found in food and food packaging, commercial household products such as stain and water-repellent fabrics, nonstick products, polishes, paints, cleaning products, and fire-fighting foams.
As scientists learn to detect these low-concentration chemicals, we must all rely on public health researchers and policy-makers to keep pace and provide steady and prudent guidance on how society should adapt and respond to this new information.
Energy consumption at our operating facilities and offices account for only 2% of our overall carbon footprint. And interestingly, we generate substantially more electricity than we consume, as shown in the graphic here. Still, we are committed to energy efficiency improvements because most measures also yield safer and more productive work environments for our employees.