Fuel storage is a central part of farm management, keeping tractors, trucks, irrigation pumps, and small engines running day after day. Most farms rely on both diesel—for tractors, combines, and generators—and gasoline—for pickups, ATVs, and small engines. The question many farmers face is whether to use split farm tanks (single tanks divided into compartments for multiple fuels) or maintain separate tanks for each type.
At Mills Equipment, we’ve worked with farms of all sizes to evaluate fuel storage needs. While split tanks can save space and simplify logistics, they also come with unique challenges related to safety, compliance, and maintenance. This guide walks through common configurations, advantages and disadvantages, and practical factors to consider before investing in a split fuel tank system.
What Are Split Farm Fuel Tanks?
A split farm fuel tank is a storage tank divided into two or more compartments, each holding a different type of fuel. For farms, the most common split configuration is diesel in one compartment and gasoline in the other, though some tanks may include compartments for kerosene or DEF (Diesel Exhaust Fluid).
Split tanks are available in:
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Portable skid tanks: Mounted on trailers or frames for fueling in the field.
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Stationary aboveground storage tanks (ASTs): UL-142 certified, often with dual compartments separated by welded steel walls.
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Truck-mounted split tanks: Used for mobile fueling across different fields.
By combining multiple fuels in one tank system, farms reduce their footprint and centralize fueling operations.
Pros of Split Farm Fuel Tanks
1. Space Efficiency
Instead of two separate tanks, split tanks use 4 separated walls, bases, and containment. This saves valuable yard space and simplifies farm layouts.
2. Centralized Fueling
Having both gasoline and diesel in the same location allows employees to fuel different types of equipment quickly without moving between tanks.
3. Cost Savings on Installation
A single pad, containment berm, and pump system may support both compartments, lowering upfront costs compared to installing two entirely separate tank systems.
4. Flexibility for Mobile Use
Split skid tanks or trailer-mounted tanks are highly practical for field operations. Farmers can bring both fuels into the field, reducing downtime during planting or harvest.
5. Simplified Deliveries
Fuel suppliers can top off both fuels in one stop, saving time and reducing delivery fees.
Cons of Split Farm Fuel Tanks
1. Risk of Cross-Contamination
Gasoline and diesel must be carefully segregated. Even small leaks between compartments or shared piping systems can cause contamination, which is costly to remediate.
2. Compliance Complexity
UL-142 and NFPA 30 standards apply separately to diesel and gasoline. Diesel is combustible, while gasoline is flammable and subject to stricter requirements. Compartments must meet all applicable safety and venting rules.
3. Limited Capacity Flexibility
Split tanks have fixed compartment sizes. If your farm uses far more diesel than gasoline, you may run short on diesel capacity while gasoline sits unused.
4. Higher Replacement Costs
If one side of a split tank develops issues (like corrosion or leaks), the entire tank system may need repair or replacement, even if the other side is still in good condition.
5. Insurance and Inspection Hurdles
Insurers often require separate containment and labeling for gasoline and diesel, even within a split tank. Inspections may be more frequent and documentation more detailed.
Key Safety Considerations
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Labeling: Each compartment must be clearly labeled “Diesel” or “Gasoline.” Mislabeling can lead to fueling mistakes with costly engine damage.
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Venting: Gasoline compartments require flame arrestors and stricter venting standards than diesel. Both must be designed separately.
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Containment: Spill containment must account for the largest compartment volume, and both compartments count toward SPCC thresholds (1,320 gallons).
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Pumps and hoses: Use dedicated pumps and hoses for each fuel type. Color-coded handles (green for diesel, red for gasoline) help prevent cross-use.
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Fire protection: Gasoline requires a greater distance from structures, ignition sources, and electrical systems than diesel.
When Split Tanks Work Best
Split tanks are especially beneficial for:
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Small to mid-sized farms with moderate fuel usage of both diesel and gasoline.
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Operations with mobile fueling needs, where field fueling efficiency outweighs capacity flexibility.
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Farmyards with limited space, where installing two full-size tanks is impractical.
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Farms prioritize convenience over maximizing single-fuel storage.
When Separate Tanks May Be Better
Separate tanks are often preferable when:
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The farm uses significantly more diesel than gasoline (common for row crop and grain operations).
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Compliance requirements are stricter in your state for gasoline tanks.
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Insurance premiums are higher for mixed storage setups.
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The farm already has established containment and fueling infrastructure.
FAQs About Split Farm Fuel Tanks
Are split tanks legal for storing gasoline and diesel together?
Yes, provided they meet UL-142 certification, NFPA standards, and EPA SPCC requirements. Compartments must be fully segregated with proper venting and labeling.
Do split tanks require double containment?
Yes. Both fuels count toward SPCC thresholds, and spill containment must be sized for the largest compartment.
Can I retrofit an existing tank into a split configuration?
No. Tanks must be manufactured and certified as split tanks. Retrofitting an existing tank violates safety and insurance rules.
Are split tanks more expensive?
Upfront cost per gallon is higher than a single-fuel tank, but farms save on installation, delivery, and space compared to separate systems.
How do I prevent fueling mistakes?
Use color-coded nozzles and labels (green for diesel, red for gasoline) and train employees on fueling procedures.
Do split tanks last as long as separate tanks?
Yes, provided they are maintained properly. Lifespan typically runs 15–25 years, depending on material and corrosion protection.
Supporting Smarter Fuel Storage
Split farm tanks offer a practical solution for many farms balancing diesel and gasoline needs, but they are not one-size-fits-all. They save space, reduce installation costs, and improve convenience, but they also bring compliance challenges and less flexibility in capacity.
At Mills Equipment, we help farmers evaluate whether split tanks are the right choice for their operations. We provide UL-certified split and single-fuel tanks, containment systems, and fueling equipment designed to meet both safety and regulatory requirements. By choosing the right configuration, farms can reduce risks, streamline fueling, and protect long-term investments in their equipment.