Composting vs Landfilling Organics, How to Compare the Cost per Ton

To compare composting and landfilling fairly, put both on a full cost per ton basis: for the landfill, include the value of the airspace each ton consumes, its share of gas, leachate, closure and post-closure obligations, and compliance; for composting, include annualized capital, operations, residuals sent back to disposal, and product revenue, then credit the disposal it avoids. Most comparisons go wrong because they set a compost facility’s full cost against the landfill’s gate rate, which may not recover the landfill’s own long-term costs. This guide gives a worksheet with variables, not prices, so your finance staff can fill it in with your numbers.

Key takeaways

Compare full cost per ton on both sides, not a compost quote against a landfill tip fee.
The landfill’s largest hidden cost is the airspace a ton consumes. Value it at what replacing that capacity would cost you, not at zero.
Federal rules require municipal landfill owners (all except state and federal government entities) to estimate closure and 30 years of post-closure care in current terms and adjust both estimates for inflation every year. Those estimates belong in the per ton cost.
On the composting side, residuals that go back to the landfill and product revenue (or the cost of giving product away) can swing the result.
Run the comparison over the same period for both options, with low, expected and high cases, and report non-cost factors such as mandates and methane separately.

Why gate rates mislead

A landfill’s posted rate is a pricing decision. It may be set to recover current operations, to compete with a neighboring site, or to keep rates steady for residents. It may or may not include the full cost of replacing airspace, funding closure and decades of post-closure care, or upgrading the gas system as the site grows. A compost facility’s cost estimate, by contrast, usually includes capital and operations from day one. Setting one against the other compares a partial cost to a full one.

The fix is to rebuild both sides from their cost components, per ton, over the same planning period. For the composting side, the lifecycle cost guide lists the drivers in detail. Sustainable Generation (SG) makes a related argument in its three-part series, starting with Part 1, on infrastructure decisions that affect budgets for decades: that a low upfront price can become the most expensive decision when the costs show up later as expansion delays, community opposition, retrofits or enforcement.

The landfill side: full cost per ton

Airspace

Every ton placed consumes permitted volume. Convert that to a cost:

Cubic yards per ton (Y) = 2,000 / in-place density in pounds per cubic yard, from your surveys.
Airspace value per cubic yard (A) = what it would cost you to replace that capacity: the next cell, an expansion, a new site, or long-haul transport to another landfill once yours is full. Your landfill engineer and finance staff should agree on the basis.
Airspace cost per ton = Y x A.

The airspace and diversion guide shows how to measure Y and estimate years of life gained.

Closure and post-closure

Under 40 CFR 258.71, owners (other than state and federal government entities, which 40 CFR 258.70 exempts) must prepare a detailed written estimate, in current terms, of what a third party would charge to close the largest area that would ever need final cover, update it for inflation every year while the unit is active, and carry financial assurance for it. Under 40 CFR 258.72, they must do the same for post-closure care, covering annual and periodic costs over the whole post-closure period. 40 CFR 258.61 sets that period at 30 years unless the state changes it, and it includes cover maintenance, leachate collection, groundwater monitoring and gas monitoring.

Closure and post-closure cost per ton (C) = (closure estimate + post-closure estimate) / total tons the landfill will receive over its permitted life, or the share your accounting system already assigns per ton.

Gas, leachate and compliance

Gas system cost per ton (G): wells, headers, flares or energy equipment, monitoring and repairs, spread over tons received. Organics drive gas generation, as the guide to landfill methane rules and organics explains.
Leachate cost per ton (L): collection, hauling or treatment, and the share that relates to wet organic waste.
Compliance and monitoring cost per ton (M): groundwater, surface emissions, reporting and permit fees.

Operations and fees

Operating cost per ton (O): equipment, fuel, labor, daily cover.
Fees and taxes per ton (F): state disposal fees, host fees, or surcharges that apply to disposal but not to composting.
Haul cost per ton to the landfill (H_L).

Full landfill cost per ton = (Y x A) + C + G + L + M + O + F + H_L.

The composting side: full cost per ton

Capital

Spread capital over its useful life with a capital recovery factor, the standard engineering economics formula:

CRF = i(1 + i)^n / ((1 + i)^n minus 1), where i is your borrowing or discount rate and n is the life in years.
Annualized capital (K_a) = capital cost x CRF.
Capital cost per ton = K_a / design tons per year.

Use separate lives for separate assets (pad, aeration, covers, mobile equipment), because they wear out at different rates. If you lease instead of buy, the lease payment replaces the capital line. SG’s leasing program names bridging gaps between grant phases as a municipal use, and the guide to leasing vs buying sets out the trade-offs.

Operations

Operating cost per ton (P): labor, fuel, power for blowers, water, maintenance, cover handling, monitoring, lab testing, permit compliance.

Residuals

Contamination, oversize and rejects go back to disposal.

Residual cost per ton (R) = residual fraction (r) x full landfill cost per ton.

Use the full landfill cost here, not the gate rate, for consistency.

Product revenue

Net product value per ton of feedstock (V) = (compost sold per feedstock ton x net price) minus distribution cost. V can be zero or negative if you give compost away or pay to move it. If city departments use the compost in place of purchased material, count the avoided purchase. In California, SB 1383 requires cities and counties to procure an annual quantity of recovered organic waste products, with a target CalRecycle sets from population (CalRecycle procurement), so a city’s own use may be required anyway; see key SB 1383 requirements.

Haul

Haul cost per ton to the compost site (H_C).

Full composting cost per ton = capital per ton + P + R + H_C minus V.

The worksheet

Fill one column for each option. Every value is a variable to replace with your own data.

Line	Landfill	Composting	Source of the number
Airspace consumed (Y x A)	Yes	Only through residuals	Surveys, replacement capacity estimate
Closure and post-closure (C)	Yes	Through residuals	40 CFR 258.71 and 258.72 estimates
Gas system (G)	Yes	No	Gas system budget
Leachate (L)	Yes	Pad water handling sits in P	Leachate budget
Compliance and monitoring (M)	Yes	Included in P	Permit and monitoring budget
Operations (O or P)	Yes	Yes	Operating budgets or vendor estimates
Fees and taxes (F)	Yes	Usually not	State and local fee schedules
Capital per ton	Usually already sunk	Yes (CRF method)	Capital estimate, rate, asset lives
Residuals (R)	No	r x full landfill cost	Pilot data, processor records
Product value (V)	No	Subtract	Market survey, city use
Haul (H_L or H_C)	Yes	Yes	Route analysis
Full cost per ton	Sum	Sum minus V

A worked example in symbols

Suppose your engineer reports Y = 1.4 cubic yards per ton (assumed) and your residual fraction from a pilot is r = 0.10 (assumed).

Landfill full cost per ton = 1.4A + C + G + L + M + O + F + H_L.
Residual cost per compost ton = 0.10 x (1.4A + C + G + L + M + O + F + H_L).
Composting full cost per ton = K_a / tons + P + step 2 + H_C minus V.
Composting is the lower cost option per ton when step 3 is less than step 1.

Rearranging step 4 shows which variable matters most. If A is large (scarce airspace, an expensive next cell), the landfill line grows by 1.4A per ton and composting gains ground quickly. If A is small and the landfill has decades of capacity, composting has to compete on operations, product value and mandates.

Sensitivity: which variables swing the answer

Variable	When it favors composting	When it favors landfilling
Airspace value (A)	Landfill near capacity, next cell hard to permit	Decades of permitted capacity
Residual fraction (r)	Clean source separated feedstock	Heavy contamination
Product value (V)	Steady city use or local buyers	No outlet, compost must be hauled away
Haul (H_C vs H_L)	Compost site on or near the landfill	Compost site far from routes
Utilization	Facility runs near design tons	Tonnage arrives slowly, capital spread thin
Fees (F)	Disposal fees apply to organics	No disposal fees

Utilization deserves its own warning. A compost facility sized for year ten but receiving year one tonnage carries its whole capital cost on fewer tons. The tonnage forecasting guide shows how to phase capacity to the forecast. Modular systems can help: SG rates the SG HEAP® System at 1,000 to 100,000+ tons per year and the SG BUNKER® System at 5,000 to 500,000 tons per year, and it describes the SG MOBILE® System as installed in days to weeks, depending on the site.

What the cost comparison leaves out

Report these beside the cost result, not inside it:

Mandates. In California, SB 1383 sets a target of 75% less organic waste sent to landfills, according to CalRecycle. A mandate is not optional because one option costs less.
Methane. EPA estimates that landfilled food waste is the source of about 58% of fugitive methane from municipal landfills (EPA). EPA’s Waste Reduction Model compares greenhouse gas outcomes of landfilling, composting and other options.
Neighbors and permit risk. A compost facility that generates complaints carries a cost no worksheet captures well. Covered aerated static pile composting with a GORE® Cover is designed to contain odors at the pile; SG’s Part 2 article on how technology choices drive performance and risk in year 1, year 5 and year 15 gives SG’s view of that risk over time.

Steps to run the comparison

Agree the planning period and discount rate with finance staff.
Get Y, remaining airspace and the replacement capacity basis for A from the landfill engineer.
Pull the current closure and post-closure estimates and gas, leachate and compliance budgets.
Get composting capital and operating estimates for two or three methods, with asset lives.
Run a pilot or use comparable data for r and for compost quality. SG’s pilots and demos page describes running batches of your own feedstock to produce data for permits, grants or board approval.
Fill the worksheet for low, expected and high cases.
Report the result with the non-cost factors listed beside it.

FAQ

Why not just compare the compost facility’s cost to our landfill tip fee?

Because the tip fee is a price, not a cost. It may leave out the value of the airspace each ton uses, part of the closure and post-closure obligation, or future gas system work. Rebuild the landfill’s full cost per ton from its components, then compare it with the full composting cost on the same basis and period.

How do we put a value on landfill airspace?

Ask what replacing it would cost: building the next cell, permitting an expansion, siting a new landfill, or hauling waste elsewhere once the site is full. Divide that by the cubic yards it would provide to get a value per cubic yard, then multiply by the cubic yards each ton consumes from your surveys.

Should product revenue be counted?

Yes, but conservatively. Use a net figure after screening, testing and distribution, and allow for seasons when compost does not sell. If city departments use the compost instead of buying soil amendments or mulch, count the avoided purchase. If you expect to give it away or pay to move it, enter a negative value.

Does the comparison change if the compost site is on the landfill?

Often, yes. Haul distance falls, the scale house and equipment may be shared, and residuals have a short trip back to the working face. Shared costs need a fair allocation so neither side looks artificially cheap. The composting at landfills guide covers siting on landfill property.

Next step

Fill in the worksheet with your own landfill data first, then ask for composting estimates to complete the other column. SG’s consulting page and pilots and demos program describe SG’s facility planning, pre-design and pilot demonstration support.

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