Transfer Station design is tough and tedious. The design affects daily operations, capital layout, operating costs, maintenance costs, customer acquisition, safety, relationship with the host community(ies), labor costs, and many other items, so it can’t be taken lightly.
Transfer Station facilities may seem simple but are very complicated to design and construct to handle the daily activities and abuse that they endure. Most people look at a transfer station and think, metal building and concrete floor… what’s so difficult about that? In short, the design must consider the following items:
- Owner’s Operational Preference & Safety Requirements,
- Local Municipality Requirements / Host Agreements / Design Requirements,
- Environmental Agency Design Requirements,
- Materials Received & Sorting Requirements,
- Customer Make-Up,
- Outbound Material Load Out & Schedule,
- Site Size, Location & Restrictions,
- Requested Life of Facility,
- Growth Expectations / Facility Expansion, and
- Other Activities Occurring on Site.
So, let’s touch briefly on each of these items that must be considered when designing a transfer station facility. In subsequent blogs, we will dive into more detail on each of these design requirements.
Owner’s Operational Preference & Safety Requirements: Every site is unique, and each owner has their operational preferences. This goes from traffic flow requirements, equipment used on site, scaling preferences, software, operating hours, materials to recover (if any), materials used within the building, vehicle time on site, activities allowed on site, employee count, whether they operate it or subcontract out that portion and many other items. A good design firm gathers as much about the owners operating preferences as possible BEFORE they start the design process. We do this in the scoping phase, also known as preliminary design. Safety is a discussion all on its own with the operator and needs to be clearly understood by the design team.
Local Municipality Requirements / Host Agreements / Design Requirements: As all the operators out there know, the local jurisdiction can impose many different requirements on the company. This can range from improvements outside of your property lines, traffic/routing requirements, recovery/diversion requirements, exterior façade / aesthetic requirements, hours of operations, parking, stormwater, and many other factors that must be gathered at the onset of the design or during the preliminary design phase. Also, part of this will be the fire marshal requirements.
Environmental Agency Design Requirements: Depending on the state the facility will be located, each agency has its preference and most of this discussion will take place during the environmental permitting stage. Items that typically are discussed at this point are throughput allowed on an annual or daily basis, where the material will go, size of tipping floor, operating / equipment to be used, overhead door requirements, inbound material hours allowed, outbound materials handling, employee requirements, inspection requirements, leachate control, radiation detection requirements (if needed), and other various topics depending on the permit process in your state.
Materials Received & Sorting Requirements: While this is touched on in previous sections above, it’s important for the design because the transfer station design firm needs to understand the material make-up, quantities, storage requirements, outbound loading process, and what the owner will do with the materials while on site. For instance, if you are taking MSW and some recyclables, you will want to make sure that the water runoff from the MSW doesn’t contaminate the recyclable materials because then they lose value. The design firm must understand how you are going to receive, handle and send out all materials received so they can plan your floor accordingly. Some items (compost, C&D) can be stored outside the transfer facility but each governing authority treats this differently, so you have to understand ALL the requirements.
Customer Make-Up: This is important because if the transfer facility only takes internal volume, the site should be straightforward to get trucks in and out quickly. However, when you start mixing in third party haulers (whether it’s other waste trucks or small dump trucks, drywallers, demo firms, landscapers, roofers, etc.) it becomes increasingly more difficult to ensure that you have enough bays in the facility to allow for your
trucks to get in and out quickly and to allow for the third party to safely dump within the transfer station in an expedited manner. Now, throw in residents coming to dump small truckloads, garbage bags, and other customers that could be paying cash and your job becomes even more difficult when designing the transfer station to be efficient.
Outbound Material Load Out & Schedule: The outbound schedule is typically driven by the facility receiving the material and the hours of operation your transfer station is allowed to be open. As an example, if a landfill is 2 hours away and doesn’t open until 6 AM, you would want to have trailers loaded and on the road by 4 AM. However, if your operating agreement doesn’t allow you to operate until 5 AM, you will need to pre-load trailers the day before, so the hauler can pick them up and leave at 4 AM without you opening. On the other hand, if the landfill closes at 4 PM but you receive material until 5 PM and it’s a 2-hour drive to the landfill, the material on your floor will need to be either stockpiled until morning OR pre-loaded into trailers because the last load going to the landfill will likely be no later than 1:30 so they can be tipped and out of the landfill by 4 PM. This means you have 3.5 hours of receiving material, stockpiling on your floor that you can’t haul off-site. You have the same issues with recyclables that need to be dealt with. We call this Floor Balancing. This is an exercise we conduct during the scoping/preliminary design phase.
Site Size, Location & Restrictions: Some sites have plenty of acreages, some are tight, some are rural, some are in the city, some are near residences (some are not), and some have heavy stormwater storage requirements, and some don’t. There are hundreds of items to consider during the site selection process. Cambridge’s scoping or preliminary design phase often includes assisting clients with this process by conducting site walk-thru, preliminary layouts, traffic pattern assessments, conceptual designs, and budgets for various options being considered.
Requested Life of Facility: Every owner has an idea of the capital outlay they want to stay within or the limit of financing available, as well as what kind of annual operating expenses they can handle based on the projected revenue of the facility. Depending on the owner’s preference, we design the facility to meet these requirements. Several things that are done to modify the “life expectancy” or to “limit the annual OPEX or repair requirements” are thicker concrete push walls, thicker tipping floor, more robust overhead door protection, stick-built scale house vs. modular trailer, galvanizing the metal building, heavy-duty deflector vs. lighter weight design, and other various items we work through with the owner. The transfer station design can vary greatly and affects the costs in several different ways that we work with the owner in determining their goals.
Growth Expectations / Facility Expansion: Markets expand and contract and each owner has different ideas on what they expect for the expansion of their market and their internal volume and the ability to add third-party customers. This must be clearly understood by the transfer station design firm and planned into the overall site design so that when the time comes to expand it doesn’t hinder their ongoing operations too much. Along with volume growth, the “evolving ton” is a real thing. Just because you accept and sort certain materials today, doesn’t mean that 5 years from now you will have the same operation. You need to plan for changing operations and flexibility as much as you can today.
Other Activities Occurring on Site: Outside of just the transfer station design mentioned above, some companies combine their transfers with hauling companies, closing landfills, recycling facilities, compost facilities, and other various operations. A good design firm understands the entire scope of the operations on site and incorporates the transfer station into it seamlessly and, more importantly, safely.
As I mentioned when this blog started, transfer station design is not easy and can’t be over-simplified. You must hire the right partner to help you through everything mentioned in this article as well as all the other items I didn’t get to. Cambridge has completed over 120 solid waste facilities, including over 60 transfer stations, whether it be new construction, modifications, improvements, or otherwise. We can help you get the right facility for what you need. We pride ourselves on durable, cost-effective facilities. Cost-effective, not only in construction but also in helping you manage your operations costs.
Jeff Eriks – President
