How do you set up a fleet fuel quality management program?

Fuel filter changes on your fleet trucks used to follow a predictable maintenance schedule. Now some trucks need new filters every few weeks. Two vehicles have already needed injector replacements this year. And the trucks that fuel at the cardlock across town don't seem to have the same problems.

Everyone suspects the bulk storage tank. But nobody has actually tested the fuel.

That's where a fleet fuel quality management program comes in. Instead of guessing what's causing the problems, you establish a baseline for fuel quality, put routine monitoring procedures in place, and establish specific limits that tell you when corrective action is necessary.

Done right, the program takes fuel quality from something you only think about when there's a problem and turns it into something you can actively manage. And that gives you a way to connect fuel quality with maintenance costs, filter replacement intervals, and even your fleet's cost per mile.

What Does a Fleet Fuel Quality Management Program Include?

A fleet fuel quality management program covers the bulk storage tank, the fuel coming into it, and the fuel being dispensed into vehicles. It includes tank inspections and baseline testing, delivery checks, appropriate chemical treatment, water monitoring and removal, routine fuel testing, written action limits, and recordkeeping.

Why is this more important today than it was 20 years ago?

One reason is that today's ultra-low sulfur diesel (ULSD) is different from the diesel fuel fleets used decades ago. Modern refining processes have changed fuel composition, and some of the naturally occurring compounds that contributed to fuel stability may be reduced during processing. Depending on the fuel's composition and storage conditions, oxidation and sediment formation can become concerns during extended storage.

Microbial contamination is another concern, especially when water accumulates in storage tanks. Microorganisms can grow at the fuel-water interface, producing biomass and other byproducts that contribute to filter plugging and corrosion.

Bell FTS service experience suggests that untreated ULSD stored under typical conditions may begin developing significant quality problems within 6 to 12 months. That's not a fixed expiration date, but it illustrates why fuel turnover and storage conditions matter, particularly for seasonal equipment and low-use tanks.

The tank itself deserves attention, too.

In a 2016 investigation of underground storage tanks containing diesel fuel, the EPA found moderate or severe corrosion in 35 of the 42 tank systems examined. Fewer than 25% of the owners were aware of the corrosion before the investigation. The agency also detected ethanol in 90% of the fuel samples, suggesting that cross-contamination can occur during fuel distribution.

The EPA didn't identify one definitive cause of the corrosion, although microbiologically influenced corrosion was considered a possible contributor. And while the study wasn't designed to represent every diesel storage tank in the country, its findings demonstrated why internal tank inspections are important.

Bell FTS approaches these problems by combining fuel testing, appropriate chemical treatment, and mechanical services such as filtration, fuel polishing, and tank cleaning. That's important because no single treatment method addresses every potential fuel quality problem.

Start the Program With a Baseline Test of Every Bulk Tank

Every effective fleet fuel quality program starts with knowing the condition of the fuel and the tanks you're managing.

Begin by making an inventory of every bulk storage tank. Record its capacity, age, fuel type, and average monthly throughput. Include information about the tank's construction, maintenance history, and any recurring fuel-related problems.

Then establish a fuel quality baseline using a comprehensive testing package, such as the Bell FTS Mission Critical ASTM test slate, along with ATP microbial testing. For underground tanks, consider an internal camera inspection to evaluate the condition of accessible components.

These results give you a starting point and help identify which tanks need immediate attention.

Fuel turnover is particularly important.

A 10,000-gallon tank that turns over every week presents a different set of storage concerns than a 2,000-gallon tank at a satellite yard that supplies snowplows or standby generators and might turn over only twice a year.

Fuel in low-turnover tanks has more time to age and oxidize. Water can accumulate, and microbial contamination can develop if conditions are favorable.

Record the biodiesel content of the fuel, too. Biodiesel blends can introduce additional storage considerations, including oxidation stability and water management. The extent of those concerns depends on the blend percentage, fuel quality, and storage conditions.

Sampling is especially important because contamination isn't always distributed evenly throughout a tank.

Use appropriate sampling equipment to collect a bottom sample and a representative sample of the stored fuel. Bottom samples can reveal accumulated water, sludge, sediment, and contamination near the fuel-water interface. A representative fuel sample helps establish the condition of the fuel being stored and supplied to equipment.

If you want to evaluate the fuel actually reaching your vehicles, collecting an additional sample from the dispensing system can be useful.

For underground tanks, a camera inspection through an accessible opening can help identify corrosion on internal metal components, including drop tubes, probes, and other equipment. The EPA specifically recommended that diesel UST owners investigate the condition of their tank interiors following its 2016 corrosion study.

Bell FTS uses the Mission Critical ASTM testing package and ATP microbial testing to establish the baseline and identify where corrective action is needed.

That might mean chemical treatment, water removal, fuel polishing, or tank cleaning. And if the fuel is already outside acceptable specifications, it may require a more extensive response.

What Fuel Quality Limits Should a Fleet Write Into the Program?

A fuel quality management program needs written limits for water, sediment, microbial contamination, and cold-weather performance, along with specific actions to take when those limits are exceeded.

For example, ASTM D975 establishes a maximum of 0.05% water and sediment by volume for applicable diesel grades, measured using ASTM D2709. Bell FTS may also use a Karl Fischer water result of 200 ppm as an operational action threshold, depending on the fuel and storage conditions.

Those are two different measurements, and they shouldn't be treated as interchangeable.

The program should also establish procedures for responding to free water, increasing microbial activity, and fuel that may not perform adequately in cold weather.

And don't overlook the importance of identifying who's responsible for taking action when a test result exceeds an established limit.

Written limits accomplish two important things.

First, they tell your technicians what to look for and what to do when something falls outside the acceptable range. Second, they turn laboratory results into actionable information.

For example, a water and sediment result of 0.08% by ASTM D2709 tells you the fuel exceeds the 0.05% maximum specified by ASTM D975 for applicable diesel grades. Without a written action limit, that result might sit in someone's inbox until filters start plugging or equipment problems develop.

Cold-weather performance deserves special consideration because the appropriate limits depend on where and when your fleet operates.

ASTM D975 doesn't establish one cloud point requirement for the entire country. Instead, it provides guidance based on regional temperatures and seasonal conditions. Fleets should establish cold-flow requirements that reflect their actual operating environment, including the temperatures equipment may experience overnight or during severe winter weather.

And remember, a limit is only useful if you're testing often enough to catch problems before they become expensive.

A fuel sample that passed in March doesn't necessarily tell you what condition the fuel will be in by August.

How Should a Fleet Check and Treat Each Fuel Delivery?

Every fuel delivery should be checked before it's accepted into bulk storage, and any required fuel treatment should be added at the appropriate time to ensure proper mixing.

Start by confirming that the delivered fuel matches what you ordered. Check the product grade, biodiesel content, and delivery documentation. Where practical, collect a representative sample from the transport before unloading.

A simple visual inspection can catch some obvious problems.

ASTM D4176 provides a procedure for evaluating fuel appearance, including visible water, sediment, and haze. Fuel that appears cloudy or contains visible contamination deserves further investigation before it's accepted.

But a clear-and-bright appearance doesn't guarantee that fuel meets every ASTM specification. Problems involving oxidation stability, dissolved water, or other fuel properties may not be visible.

Consider keeping a properly labeled retained sample from each delivery. Record the date, supplier, delivery identification, and any other relevant information. If a fuel quality problem develops later, those samples may help establish whether the problem originated with the delivered fuel or developed during storage.

Check the receiving tank for water before the delivery, and document any unusual conditions.

Fresh fuel entering a tank can stir up sediment, water, and other material that has accumulated on the bottom. When operations allow, giving the fuel time to settle before dispensing can reduce the likelihood of carrying that material into vehicles.

Fuel treatment is another important part of the delivery process, but the right treatment depends on the condition of the fuel and the problems you're trying to prevent.

For example, Tank Treatment SDF can be used as part of a preventive maintenance program to help manage sludge and deposits while providing corrosion protection. At a treatment ratio of 1:10000, a 5,000-gallon delivery would require 0.5 gallon of product.

Where microbial contamination is a concern, Bellicide may be incorporated into the program at the appropriate maintenance or corrective treatment rate. The decision should be based on the tank's condition, microbial testing history, and the product's registered label directions.

For tanks with slow fuel turnover, Dee-Zol Life can provide additional protection against fuel degradation during storage. At its recommended 1:2000 treatment ratio, a 5,000-gallon delivery would require 2.5 gallons.

Cold-weather treatment should also be planned ahead of the season. Antigels like Diesel Gel Defense work best when added and thoroughly blended before the fuel reaches temperatures where wax crystals begin forming. Typically, this is around freezing (10-12 degrees above the Cloud Point). Don't wait until the fuel has already gelled to start thinking about winter treatment.

The important thing is to match the treatment to the actual fuel quality risks, rather than assuming every tank needs exactly the same combination of products.

Chemical treatment has its limits, however.

If a fuel delivery fails critical specifications, such as flash point or distillation characteristics, you shouldn't assume an additive can correct the problem. Depending on the nature of the contamination, the fuel may need to be rejected, removed, or handled through an appropriate corrective process.

That's another reason why checking fuel quality before it enters your storage tank is so important.

How Often Should a Fleet Test Stored Diesel and Change Filters?

Fleet operators should check bulk storage tanks for free water at least monthly, perform microbial testing on a regular schedule, and conduct comprehensive fuel quality testing at least annually.

The appropriate testing frequency depends on several factors, including fuel turnover, storage conditions, the presence of biodiesel, and the tank's history of contamination.

Bell FTS commonly recommends a baseline program that includes periodic water checks, semiannual ATP microbial testing, and an annual ASTM fuel quality test package. Tanks with a history of contamination, frequent deliveries, or other elevated risks may justify more frequent monitoring.

For federally regulated underground storage tanks, 40 CFR 280.36 generally requires walkthrough inspections every 30 days, including checks of spill prevention and release detection equipment. Those inspections aren't the same as fuel quality testing, but they provide a convenient opportunity to incorporate additional water monitoring into the maintenance routine.

And don't overlook one of the most useful sources of information you already have: your fleet's fuel filter replacement records.

Most fleet maintenance departments track filter changes. But how often do they look at that information specifically for signs of fuel contamination?

Start recording fuel filter replacement intervals by vehicle, along with dispenser filter changes at each bulk storage location. If your dispensing equipment has differential pressure gauges, record those readings as well.

Then look for patterns.

If multiple vehicles fueled from the same storage tank suddenly begin experiencing shorter filter life, that points toward a possible problem with the bulk fuel supply.

On the other hand, if one truck is repeatedly plugging filters while other vehicles using the same fuel operate normally, the problem may be isolated to that vehicle's tank or fuel system.

Those distinctions can save considerable time and money by helping you investigate the right source of contamination.

ATP microbial testing adds another useful layer of information.

By tracking microbial activity over time, you can identify increasing contamination before it becomes severe enough to cause widespread filter plugging or equipment problems.

A single ATP result tells you something about the condition of the sample at that moment. Repeated testing gives you a trend, and that trend can help determine whether preventive treatment is working or whether more aggressive corrective action is necessary.

What Does a Fleet Fuel Quality Program Cost to Run?

Based on Bell FTS service experience, a preventive fuel quality management program that combines testing and treatment may cost approximately $700 to $2,000 per tank annually. Actual costs depend on tank size, fuel turnover, testing frequency, treatment requirements, and the number of storage locations involved.

Compare that with the cost of addressing contamination after it becomes a serious problem.

Emergency fuel polishing may cost several thousand dollars, while extensive tank cleaning can cost considerably more. And those expenses don't include fuel filter replacements, injector damage, equipment downtime, or lost productivity.

A preventive program isn't just about keeping the fuel clean. It's about reducing the likelihood of those larger, unexpected expenses.

The program also needs someone who's responsible for making sure it gets done.

For most fleets, that responsibility will fall to the maintenance manager or another person already responsible for fuel purchasing, storage, or equipment maintenance.

Keep fuel testing results, delivery records, treatment history, and filter replacement information together whenever possible. Ideally, that information should be accessible through the same maintenance management system you're already using.

That makes it easier to identify relationships between fuel quality and maintenance costs.

It's also important to recognize what a fuel quality management program can't do.

It can't make consistently poor-quality fuel from a supplier meet the proper specifications. That's a purchasing and supplier-management issue. Make sure your fuel contracts identify the applicable ASTM D975 requirements, and establish procedures for documenting and addressing questionable deliveries.

For smaller fleets with only one storage tank, a comprehensive program may not be necessary. An annual fuel quality test, periodic ATP testing, and routine water monitoring may provide an appropriate starting point.

Bell FTS offers Fuel Secure as a way to put routine fuel testing and monitoring on a scheduled program. Depending on the service level, Fuel Secure can include ASTM testing, microbial monitoring, trend analysis, and treatment recommendations.

The objective is to make fuel quality management predictable rather than waiting until a contamination problem forces you to act.

Start With Your Slowest Tank

If you're not sure where to begin, start with the bulk storage tank that has the lowest fuel turnover.

Maybe it's the tank at a satellite yard that supplies seasonal equipment. Or perhaps it's the tank that feeds your standby generators and only gets replenished a few times a year.

Those are the kinds of tanks where fuel quality problems can develop without anyone noticing until the equipment is needed.

Start with a baseline fuel quality assessment using a comprehensive ASTM testing package, such as the Bell FTS Mission Critical test slate, along with ATP microbial testing.

The results will help you determine whether the fuel needs corrective action and what kind of ongoing monitoring makes sense.

And once you've established that baseline, you can begin building a fuel quality management program for the rest of your fleet.

Bell FTS can help with testing, treatment recommendations, and ongoing monitoring through its Fuel Secure program.

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Prefer to talk it through? Call Bell Fuel & Tank Services at 407-831-5021.