The Debate Over the Highest and Best Use of Organics

By Elizabeth Lowell

Recently, there has been a lot of debate over organics in the landfills and a landfill’s role in generating energy in the form of landfill gas. Today’s landfills are constructed as sanitary landfills, meaning they have a liner and they are sealed with a cap when full. The material disposed into them is compacted very, very tightly. In practice, this turns landfills into great big anaerobic digesters that produce a form of biogas with around 50% methane content.  The amount of electricity a landfill can generate and its emissions of greenhouse gas emissions are determined by its landfill gas capture efficiency. Just like at wastewater treatment plants, dairy farms, and high solids anaerobic digesters, in landfills the greatest producer of biogas is organic waste like yard clippings and food scraps.

Here is the debate: Should organics be dumped in landfills that capture biogas and generate energy? Or should they be diverted, even banned, from landfills and sent to composting, and increasingly anaerobic digestion, facilities?

BioCycle Magazine’s May 2010 issue was titled Putting the Landfill Energy Myth to Rest and included a 12-page article covering everything from gas generation and decomposition rates at landfills to the nutrient content in organic waste and various organic processing technologies. A complimentary PDF of the article may be downloaded from BioCycle: http://www.jgpress.com/1005_lem/bc1005lem.html. Days after the article hit the presses, Florida Governor Charlie Crist vetoed a bill that would have overturned a state ban on disposal of leaves and other yard waste in landfills. In his letter to the state legislature explaining his veto, the Governor stated, “Although the bill requires landfills to capture and make beneficial use of methane gas to qualify to accept yard trash, it directs materials to landfills that would otherwise be recycled.” The legislature has recently set a 75% recycling goal for the state. Read more on Governor Crist’s veto at Waste & Recycling News or at Harvest Power’s blog here or here.

During the same month that BioCycle issued its report, SWANA (the Solid Waste Association of North America) approved a statement concluding that a report entitled The Importance of Landfill Gas Capture and Utilization in the U.S. “presents a valid representation of the state-of-the-art of landfill gas capture and recovery as practiced in the U.S.” SWANA went further, endorsing certain conclusions of the report as being “fully consistent with [the organization’s] mission and policies.” To read more about SWANA’s position, click here.

The Landfill Gas Capture and Utilization report details the efficiency of gas generation and capture, noting that efficiency varies from landfill to landfill based on when the capture system is put in place, the content of the waste stream the landfill receives, and many other factors. It also discusses the lower capital costs associated with gas capture systems (though it does not include an analysis of the capital and operating expenses of landfills, which serve as the gas producer), and carbon reduction credits associated with composting versus landfill gas, focusing on detectable emissions from composting operations while acknowledging that these vary greatly by facility and are substantially decreased by well-run operations.

The report, while lengthy and thorough, neglects to mention the numerous beneficial properties of compost.  Compost and compost-based soil products add nutrients, improve soil structure, aid in water retention, reduce erosion, and enhance plant growth. Compost-based soil products also offer an alternative to petro- and chemical-based fertilizers. A landfill gas capture system, no matter how efficient, will never produce compost.

These are just two of many articles and discussions on the topic. The debate continues.  We can put organic waste in landfills and produce energy.  We can put organic waste in composting facilities and benefit from the resulting compost. We can create renewable energy and high quality compost from organic waste through anaerobic digestion and composting. So what is the highest and best use (in terms of economics, efficiency, and environmental impacts/benefits) of organic waste? At Harvest, our money is on energy and compost.

Organics Recycling Industry Proactively Addressed Florida’s HB 569

By Tom Kelley

On June 2, 2010, Florida’s Governor Charlie Crist demonstrated his commitment to recycling: he vetoed House Bill 569 that would have repealed a state-wide ban related to yard waste disposal in landfills.  The organics recycling industry, led by the United States Composting Council and supported by multiple state and national organizations and companies, took a proactive stance and wrote letters to Governor Crist.  He got the message: the ban on yard waste benefits the economy and the environment. Here’s how.

• Recycling yard waste helps Florida’s small businesses. Florida has 264 registered facilities that manufacture compost and mulch from yard trimmings.  The industry provides 1000’s of jobs.  These small businesses are for the most part owned and operated by Florida residents who sell their products to other Florida businesses, keep profits within the state and use the services of other small businesses.  The Institute for Local Self Reliance recently documented that composting creates four times as many jobs as land-filling the same material.
• Recycling yard waste contributes to energy independence. Yard trimmings, due to its high lignin content, decompose slowly and only partially in a landfill environment, contributing an insignificant amount to Florida’s energy needs.  These organic materials are put to better use through composting.
• Allowing yard waste in landfills hurts the environment. Only a fraction of the methane that is generated in landfills is captured by the collection system (estimates vary considerably: the EPA puts the capture rate at 75%, while the Intergovernmental Panel on Climate Change states that over the landfill’s entire life that rate may be as low as 20%).  The methane that escapes is 30 times more harmful to global climate change than the carbon dioxide that is generated when yard waste is composted instead of land-filled. That does not count the missed benefits to the environment from composting including improved water quality, reduced irrigation needs, water conservation, healthier plants and improved storm water management. As Florida State researchers have shown, compost’s benefits would help improve yields in a number of crops.
• Recycling yard waste is in line with laws and the US EPA. Title 29, Chapter 403, section 703 of the Florida Statutes, defines “Recycling” as “any process by which solid waste, or materials that would otherwise become solid waste, are collected, separated, or processed and reused or returned to use in the form of raw materials or products.” Burying yard waste in landfills, methane collection or not, is NOT recycling, because there is no return to use.
• Recycling yard waste affirms the position of Solid Waste Management Association of North America (SWANA), the national association representing the landfill industry. A joint position statement in 2006 by SWANA and the USCC states that advances in landfill technology “should be accomplished without encouraging more organics to be placed in landfills, and without reversing hard won and effective programs and regulatory efforts that have raised recycling rates for organic residuals. Energy recovery, in bioreactor or conventional landfills, must be pursued without relaxing recycling initiatives and without improperly creating incentives for more land disposal.”

In addition, of the 23 states that have bans in place on land-filling yard debris, NONE have been overturned. In 2003, Governor Vilsack of Iowa, set a precedent for a governor’s veto of a ban repeal passing the legislature when he stated that without his veto, “this action will be a major step backwards for integrated solid waste management.”

Floridians have a proud history of protecting the environment and looking for ways to recycle organic materials.  The Florida Legislature committed a huge error in passing this legislation, but the organics recycling industry joined together to communicate the environmental and economic impacts of yard waste bans.  The good news, Governor Crist did the right thing, —he vetoed this bill.

Thank you, Florida, for continuing to recycle yard waste.

Scotland Takes Action: Waste No More for Anaerobic Digestion Output

From SEPA (Scottish Environmental Protection Agency)

Scotland’s environment watchdog has confirmed that anaerobic digestion output that is certified under the new PAS110 quality assurance scheme and that satisfies prescribed production and usage criteria will not be subject to waste regulatory controls. Anaerobic digestion is becoming an increasingly popular treatment method for biowastes, including food waste. It produces a biogas, which can be used to produce renewable heat or power, and digestate, which can be used to return organic matter to soils.

Kenny Boag, SEPA head of Waste Policy, said:

“There is significant and growing interest in the use of anaerobic digestion technology in Scotland. It is a technology that can help maximize the recovery of value and resource from source segregated biodegradable wastes, principally through the recovery of biogas and high quality soil improvers.

“SEPA is aware that sometimes regulation can be perceived as involving requirements that are not commensurate with the environmental risk attached to the particular operation. By adopting this regulatory position on PAS 110 certified digestates SEPA is satisfied that we may secure the necessary level of protection of the environment and human health in a way that will encourage development and investment in anaerobic digestion technology as a means of dealing with source segregated wastes.”

Iain Gulland, Director of Zero Waste Scotland, said:

“Anaerobic digestion has a major role to play in delivering a Zero Waste Scotland.

“Returning nutrients from food and other organic materials to the soil, so they can improve soil quality and support food production, is the kind of closed-loop approach we need.

“We welcome SEPA’s decision to take this regulatory position for PAS110-certified digestate. It will help to provide a vote of confidence in an important and burgeoning industry, and we will continue to work with producers to further build confidence in digestate.”

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