Geosyntec’s Yafrate Designs Solutions for Elevated Temperature Landfills

Elevated temperature landfills pose serious hazards; however, detecting and monitoring these conditions can be difficult.

Nick Yafrate was recently named as one of Waste360’s 40 Under 40 award recipients because of his experience working with more than a dozen elevated temperature landfills around the United States to install innovative new monitoring instruments and create long-term strategies for addressing potentially volatile landfill issues.

Waste360 spoke with Nicholas (Nick) Yafrate, a senior engineer at Geosyntec Consultants, about helping clients identify, alleviate, and prevent issues related to elevated temperature landfills.

Waste360: What are some of your major responsibilities in your current position?

Nick Yafrate: I am a project manager for solid waste facility expansions and instrumentation projects. That includes design and permitting of solid waste facilities. I also do slope stability monitoring for landfills across the country to help ensure that the landfill slopes are stable.

Within the last three or four years, much of my focus has been working with elevated temperature landfills. These are landfills where the internal temperature of the waste is increased beyond the normal landfill operating temperature. Usually, a maximum of about 130°F is expected, and elevated temperature landfills sometimes have temperatures above 300°F. There are regulatory and operational implications to having temperatures that high, and I’ve been working on sites helping to evaluate the temperatures and deal with the implications of those elevated temperatures.

Waste360: What are some challenges that you’re seeing?

Nick Yafrate: Challenges that we’ve been working on recently with elevated temperature landfills include simply monitoring the temperature within landfills. Most standard instruments that are available weren’t designed to be installed in a landfill because of the harsh conditions. The corrosive environment will damage many standard instruments. We’ve worked with instrumentation manufacturers to develop instruments that will hold up within the landfill and still be able to monitor temperature and monitor pressure.

We’ve also pioneered the use of fiber optics in landfills to measure temperatures. They were used in the oil and gas industry, and now we’ve been able to adapt them for use in landfills. Fiber optics have provided useful information for our clients that they couldn’t have obtained otherwise.

We’ve also been working with our clients to manage landfills that have elevated temperatures. Those are non-standard solid waste industry problems that we’ve been dealing with over the last five or more years.

Waste360: What do you think interests you most about what you’re doing?

Nick Yafrate: Solid waste engineering is very challenging. Things are always changing. With standard engineering materials the properties are very well-documented as to how they behave. There are relatively straight-forward ways to design with them, but solid waste is heterogeneous. You never know exactly what you’re going to get coming into a landfill. You never have the exact same problem at a site, and it’s challenging and interesting to understand what sites are dealing with and come up with solutions that work for them.

Waste360: What is something that you’re really excited about where you have worked with a client to create some sort of change?

Nick Yafrate: The use of fiber optics in landfills has been revolutionary for the way things are monitored in the landfill. We’ve been able to apply it in many different landfills and it’s something that no one had heard about four years or so ago.

Waste360: What do you wish some of your clients knew or what is something they could do differently to improve their landfills?

Nick Yafrate: Landfills sometimes run into problems when they take a different waste stream, or a new waste stream, that had not really been planned for during the design and permitting phase. It doesn’t mean that they shouldn’t take the waste, but it may have different properties and need to be managed differently than the waste properties used during the design. The waste may result in problems with slope stability, the gas system or leachate collection system, or even elevated temperatures.

Sometimes the change in waste type is not shared with the folks who designed the landfill, and the designers are then called to address the problem resulting from that waste. Although many landfills do plan ahead for potential problems resulting from alternative wastes, some could benefit from further preparation to help ensure they don’t run into problems.

Waste360: What advice might you give to a young person to encourage him to consider a career in the waste management industry?

Nick Yafrate: I think people are scared off by the image of the landfill. It’s dirty and it’s smelly, but most of the time, you’re not sitting out on a waste pile and walking through waste. Most of the time is spent designing or planning how to build it safety and efficiently. As I mentioned before, designing a landfill is often much more challenging than a standard engineering problem you face when building a house or a building where the materials are very well-known and their properties are well-documented. Designing with waste makes the work challenging and interesting.

I would also say that for young people coming into the industry, asking questions and pushing to work in the areas that they find interesting will really help to develop their careers.

Waste360: As you look out over the next few years, what would you like to see with either the industry developing new regulations or behaviors you would love to see your clients adopt?

Nick Yafrate: As we’ve been working with elevated temperature landfills, we’ve identified several factors that may be precursors or indicative of landfills that may develop elevated temperatures. Whether it’s changes in the gas or leachate properties, I think it’s something that landfill owners are going to need to become aware of so they can stop the development of an elevated temperature landfill.

Waste360: So, helping them to be more proactive about monitoring their own sites?

Nick Yafrate: Yes, I think helping landfill owners become proactive in monitoring for the conditions that may result in elevated temperatures would certainly be helpful. I think that’s coming. Based on literature that we are publishing here at Geosyntec about elevated temperature landfills and the industry as a whole, I think people will be aware of these issues in the future and be cognizant of potential problems at their sites.