Keep learning new tips and tricks every year and you will be sure to stay ahead of your odor challenges.
By Joe Provenzano
The world of waste handling is changing. In years past, landfills could operate with little to no impact on neighboring communities, but this is often not the case today. Over the years, landfills have evolved through engineered expansion and many have grown into “mega-landfills” that not only have ballooned outward, but also have risen to up to 300 feet above grade, thus increasing odor exposure to neighboring properties. At the same time, urban sprawl has created widespread situations where neighborhoods and waste handling facilities encroach upon each other, creating more potential for unwanted odor exposure. And, of course, in today’s world, negative information about odor flare-ups spreads quickly thanks to social media and the 24-hour news cycle.
All of these factors combined have created an environment where there is significantly more pressure on waste handling facility operators to mitigate and reduce the odors emitted from their facilities. Today, if a waste handling facility is affecting neighbors, the negative response is likely to be rapid and, in some cases, severe. There are widespread reports of regulatory actions and lawsuits being levied against waste handling facilities.
With all this being said, as the world of waste handling changes, so too must the odor control practices employed by waste handling companies. However unrealistic it may be for the public to expect landfills to emit no odors detectable by their neighbors, it is now incumbent upon facility operators to implement solutions that help reduce odors and thereby reducing the risk of negative reactions from neighbors.
What are the best practices for odor management in this new era? Ask any landfill operator and they will tell you that even when adhering to strict operating plans and permit rules, odor control can be a challenge. Thankfully, there are some useful tips and tricks that the savvy operator can use to improve their facility’s day-to-day odor challenges.
General Tips for Odor Control
• Encourage your operators to stay ahead of the odor problem. Once odor complaints start rolling in, it is tougher to deal with the problem because the issue is already public. By using preventative measures, you stand a better chance than when you use reactive measures.
• Do frequent and honest self-reporting when implementing an odor mitigation plan. This means checking on the success or failure of your odor mitigation measures daily and determining if you need to adjust your strategy.
• Be honest about your operations and evaluations regarding any odors present on or offsite. Without honest evaluations, mitigating potential odors is difficult. Oftentimes, local managers do not want to admit they have odors and sometimes their olfactory senses are immune to it so they cannot detect odors.
• Ensure a weather station is working every day and wind speed and direction is recorded every day of the month. This information is critical when doing an investigation resulting from a complaint.
• Outline a written odor mitigation plan and be specific about that plan. Vague plans lead to vague outcomes.
• Odor surveys should be done before, during and after operating hours as conditions change operationally as well as climatically. These surveys must be documented manually or used within an app. Barometric pressure dropping at night and early morning can carry odors further offsite; therefore, surveys are recommended to be done before and after normal operations.
• Like water sprayed directly at the source of a fire, controlling odor is most successful when odor control solutions are deployed as close to the source of the odor as possible.
• Direct application of odor control products to odorous waste or areas is effective if you use a product that eliminates odor molecules. Masking agents, encapsulators and neutralizers do not work.
• Odor molecules stick to everything and often, empty trailers (such as transfer trailers and sludge trailers) can actually smell worse than full trailers. Trailers should be washed out weekly with a product that not only cleans, but also eliminates odors. During daily operations, a simply installed spray bar can reduce the odor impact to the community when trucks leave empty.
• If you have potential on or offsite odors and you are unclear what to do, raise your hand and ask for help. There are solutions for all types of potential odors.
• Contained, controlled, tight working faces managed throughout the day to keep their size in check helps reduce odor throughout the day.
• If operations are geographically near sensitive receptors like a neighborhood or school, multiple layers of control are sometimes needed. Similar to litter control, a series of odor controls work better than just relying on one.
1. First control system is at the source, through direct application or upwind so the product can cascade over the source and impact the air. An example of this could be to install a misting system on litter fencing placed upwind of the working face. The system should have quick disconnects so they could be easily relocated. A mobile power source and pump along with a holding tank seems to be the most effective way to deliver odor control products in remote locations.
In lieu of litter fencing, bat wings, air cannons or T-posts with nozzles on them are sometimes used for intermediate control systems.
2. Second layer of defense would be downwind of the odor source but not too far from it so as to be effective. An example of this could be to install a misting system on the litter fencing located downwind from the working face.
3. Third layer of controls would be a perimeter system located at or near the property boundary between the working face and the neighbors.
This layer must be placed at the correct height interval to be effective. Establishing airflow patterns is critical in determining the correct nozzle spacing and height to effectively combat fugitive odors from escaping the site.
In instances where this third layer is visible to neighbors, the ability for the neighbor to see odor control misting can have a huge impact on their decision to file an odor complaint. (Odor complaints are commonly reported based on perception, not actual odor detection.)
• Other useful odor control devices include large fan misting systems placed near the working face located so the mist eliminates odorous gases.
• Another effective method is spraying the working face (with a water truck) at the end of the day before deploying the daily cover to eliminate odor molecules and prevent odor complaints throughout the night.
• Upon receipt of odorous waste such as wastewater sludge or industrial waste, directly apply a product to eliminate the odors prior to covering or burying.
• Mixing pits should install a perimeter misting system
• Adding certain chemicals may assist in odor reduction
• In small operations, a drum top mister may work
Landfill GCCS-Gas Collection and Control Systems
• Installation or drilling of new gas collection wells
• Trenching lateral lines between wells and to the header
• Gas well fields
• Intermediate cover with little to no well coverage
• Flare compounds
• Occasional odors can be treated with a water truck applied odor control product
• More frequent occurrences can be managed by portable or permanent odor control systems
Evaporation or Leachate Ponds
• Prevent anaerobic conditions by aeration
• Odor control product through perimeter misting
• Appropriate chemical addition to the pond
Leachate Tank Storage
• Odor control product through perimeter misting
• Appropriate chemical addition to the tanks
• Apply odor control product to all leaks/spills
Special Waste Tips
• Industrial waste from manufacturing or petrochemical plants or sludge from municipal plants sometimes contain nuisance odors like ammonia, mercaptans and strong VOCs.
• Direct application of product to a load of special waste has proven to be a very effective way to manage odorous waste. Using a product that can eliminate odor molecules can help a landfill manage waste that they ordinarily could not.
Waste companies many times have to reject odorous special waste because managing it has become problematic.
• A water truck application for large volumes or a portable, handheld sprayer can easily manage smaller volumes. Regardless of the site’s equipment capabilities, there is a solution.
• Compost operations experience issues with odorous windrows, tipping pads, grinding equipment and runoff basins.
Odors are generated when turning the windrows. Direct application to the windrows immediately after turning can provide days of sustained odor control.
If the operation resides next to sensitive receptors, a perimeter system would help prevent any impact to the community.
Transfer Station Operations
• If the Transfer station operation is located near sensitive receptors, it should have a high-pressure misting system installed to prevent impact to the neighbors.
• The system should include coverage for the following areas:
The doors should have misting down the sides and across the top to treat the air leaving the building
A misting system should be installed over the tipping floor. The system should run at all times when trash is on the tipping floor
Main doors throughout the facility should remain closed as much as possible
Any roof vents or other locations where odors can escape should be covered with odor control misting
Misting over the truck during loading, as well as staging and tarping areas is also very effective
• The transfer station floor and walls should be washed down weekly (or once a month at a minimum) with odor control products to eliminate the odor molecules and clean the walls and floor. This includes the tunnel and/or pit if applicable.
The asphalt/concrete thoroughfares around the facility should be washed down regularly with an odor control product either in a street sweeper or pressure washer
Trucks in and out of the facility carry odorous waste on their tires and undercarriage as well as leak leachate
Trash in the tunnel and/or pit should be removed daily
• Automatic doors on each end of the tunnel/pit should be in place and remain closed before, after and during truck loading.
• While waiting to enter facility, trucks should be staged as far away from neighbors as possible.
Food Waste Processing
• Food waste should be confined to the smallest working area possible.
Moisture content is not a concern
Heavy misting as close to the waste as possible both overhead and on push wall
Direct application is effective for:
Daily wash down of all surfaces and equipment with odor control product using a pressure washer
Odor control is required during offloading and loading
Storage tank vents emit odors when filling and emptying liquids
Tankers emit odors when loading liquids
Stay Ahead of Odor Challenges
Odor control is a fact of life in the modern waste handling industry. Thankfully, because of cutting edge technologies and a more widespread solid understanding of the best practices, effective odor control can be a reality at even the toughest waste handling site. Keep learning new tips and tricks every year and you will be sure to stay ahead of your odor challenges. | WA