Oil tank leak

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Max W

Feeling the Heat
Feb 4, 2021
344
Maine
We had a new oil tank installed this week. This was the result of an unfortunate event and recovery help from an unexpected source. Our smoke / CO2 alarms went off on a Saturday afternoon. We were home. A search found oil was leaking from around the welded outlet on one of two inter connected 275 gallon oil tanks that were here when we purchased the house 7 years ago. They contained about 250 gallons of #2. Surprising to me, the detectors must have picked up something in the fumes. We hadn’t smelled anything. The alarm likely saved us from a very major disaster. It turned out the second tank was in danger and also needed removal. Dealing with the leak and clean up is a story that would take more space. Between the wood cookstove and heat pump we seldom burn oil or think about the boiler or tanks. Want to put it out there if you burn oil and have an old tank you may want to regularly inspect it. I learned fuel oil can hold water and tanks rust from the inside out. If you see rust on the bottom outside of your tank it is a serious sign that all may not be well on the inside.
 
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Reportedly some insurance companies will not insure homes with tanks older than 30 Years. I am keeping an eye out for Roth type tank with second containment. My tank is around 30 years old.

There is no easy way to check the thickness, once they start leaking, the damage is pretty serious. My parents had a nice clean tank, no evidence of rust on the outside. My mom asked to to go look at it as she had seen an oil drop under it so she put a pan under it. I had them call the oil company and they were there the next morning to pump it out and replace it. They could push a screwdriver through several spots int he bottom without much effort. My experience with industrial tanks is that the corrosion is not uniform, small "pimples" will form on the bottom of the tank which will rot through quicker than the rest of the bottom. New steel tanks can be ordered and may be required to have a "double bottom" but the Roth design is superior as the inner tank is plastic so it does not rot.
 
Corrosion is rarely uniform on the interface between oxide and metal (even for aluminum).

It may look uniform on the interface between oxide and air, but that does not mean anything.

I had an oil leak here where the oil line (going down thru the slab on one side of the basement and coming up to the boiler at the other side of the basement) meets the oil filter. Turns out the Cu line had some thick orange plastic sleeve that the installers had to take off where they flared out the line. However, they did not use a utility knife to do that, but used pliers/cutters. The result were two nicks into the copper. Over the course of 5 years (and after I bought the place), vibrations opened up a crack in the Cu line, and we had a dripping leak. I think there were 5 gallons of oil under the vinyl floor before I figured out what the smell was (not being used to oil heat yet...).

That was an interesting project to do - but I would advise to avoid it at all costs. Oil soaks studs, travels up through drywall, studs, and insulation. It spreads very quickly (capillary action, I presume) under e.g. vinyl "laminate" (not sure of the name; wood looking vinyl pieces clicking together). The result is you have to rip up the floor to the slab, take out the walls including studs (load bearing walls?). Walls are easy to replace, but the floor needs cleaning. Kitty litter first. Soap and warm water and drying many times after. Then we used some powder sold at stores where plumbers get their parts that appears to neutralize the oil. Not sure what it does, but we used it. Then clean all that stuff up and seal the slab, as the oil penetrates into the concrete and you'll never get rid of the volatiles completely otherwise. Then redo the floors, paint the walls. Looks as new. (well, it IS new now...)

I did not like sealing up contamination in the slab, but I was told that's the only way.

chitload of work (or VERY expensive, according to the insurance company...) - so do check your oil tank AND lines regularly.
 
My coworker parent's house had a line under the slab. They ran out of oil one day and called for a refill of 250 gallons, it was empty again in about a day. The slab had to be removed, the worse of the impacted soil was removed and then a pump and treat system was installed in shed in the backyard. The pump and treat was there for 10 years and it needed power 24/7 to run plus annual maintenance.
 
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When we had oil our insurance Co. make us replace tanks every ten years
Made me so mad we had not touched a drop of oil in 35 years all the new tanks
never had oil put in them . They would just say new tank or double your ins. rate
Have propane now ins went down and I have had 2 full tanks for the last 3 years
not used any more than is necessary to test the system twice a winter
 
wow. I think that (replace on a schedule or else) is exception rather the rule, at least from what I've seen.
I only use the oil to make hot water - and as back-up heat (for insurance company).

Stagnant systems with fluids in them need shorter inspection intervals imo.
 
I knew we were lucky but reading these other accounts makes me feel even more fortunate that we were home and that somehow the co2 alarm sensed something. I was curious as to what leak alarms might be out there and was looking at Oil Yeller alarms. Looks like they are geared to the home owner. They set in a tray under a tank or filter. Something like that could save a lot of pain.

Our spill covered maybe an 70 ft2 area and had just about reached the corner drain that runs to daylight when I started catching it and filing 5 gallon pails while waiting for our oil company to come pump the tank into the still good one. The tech suggested cat litter and Dawn detergent for clean up. The litter worked pretty well overnight and I spread it for a second overnight. The fumes were exhausting through a fan in the bulkhead doorway temporarily sealed with Typar. All house windows were open continuously. (I ran the exhaust fan for a couple of weeks, even after the cellar smelled ok.)

Next step, wash out the spill. Some was bound to get into the drain and what would I do with the bucket of oil water mix. I’ve been around for a long time and have done things in a variety of ways, and maybe not always the best, but the cellar drain’s daylight exit is up hill from from drainage leading to the harbor. The call to Maine DEP was very uncomfortable. Am I looking at a big fine for not reporting it right away? The response was a great relief. “Glad you called. We’ll send someone right out to get it cleaned up”. A short time later a very professional energetic woman showed up and in two visits cleaned up and apparently sealed the odor with a liquid coating. She said the first concern was for our health and if we had called right away they would have pumped the tank (saving us $375 to the oil company) into their truck’s tank if we only had one. She would have set up an industrial exahust fan to keep the air in the house clear.

It turned out very small amount of oil had reached the outside and was easily cleaned with pads left to catch any more. I learned that Dawn would have broken up and dispersed oil and making it so much harder to for any outdoor clean up. This DEP rep inspected our other tank and found it also rusted and in danger of leaking. She connected us to program here in Maine, funded by oil dealers, that covered almost the entire cost of taking out the old tanks and replacing them with a new double bottomed one. That included pumping our approx 250 gallons of oil from the old to the new one.
 
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You are fortunate in Maine, they surcharge the cost of heating oil and have fund a that assists with clean up of leaking oil tank.

In my opinion a leak detector in a tray is better than nothing but definitely not a good substitute for a double contained tank. I have heard of a couple of tanks where a homeowner had attempted to store something under the tank and hit the bottom of the tank when sliding things in and out and popped a hole in the bottom. The tank drained its contents into the basement very quickly.

I also heard of one from an owner of a seasonal camp. Its had a gravity sump in the floor that was supposed to run to daylight. Some animal built a nest in the pipe and plugged it. It was in an area with shallow ground water table. The spring snow melt backed up the sump into the basement. When they found it the water was about 4 foot deep. It had "floated" the oil tank but luckily the oil line had stayed on. They did have a few containers of used motor oil that they used to light large wood stove in the basement. These leaked into the water so there was an oil slick floating on top of the water. They pumped the basement out into the woods behind the camp (rural Maine) and as the level went down there was a sheen of oil on everything. They threw a lot of stuff away and I think Dawn was used to wash everything down and out the drain. i think heating oil being lower viscosity is harder to get rid of the smell than motor oil.
 
also keep in mind incase someone is reading this and they have the same problem. the oil companies around here won't deliver oil to you if your tank is so old. i'm not sure of the age that they go buy but my aunt had a bunch of oil companies say the same to her.
 
Thanks for resurrecting this thread fbelec. Call it coincidence or synchronicity, but I had decided a few weeks ago to replace our old oil tank of unknown age. No sign of trouble, but it has obvious surface rust, and old photos of renovations tell me it has been sitting in its current location 28 years. I'm not sure if it was even new then, or just relocated from the room where the boiler previously resided. Old house, with numerous renovations since the tank was moved to its current location in the deepest bowels of the basement, so it's going to be a long and interesting day, when it happens later this month. We scheduled it to coincide with our tank running dry, or near so enough that we can run on a temporary tank a few days, in the interim.

A tech at my present oil company likes to tell a story of one old (subsequently "retired") delivery truck driver who accidentally filled a customer's basement with fuel oil. He doesn't know why the guy ignored the lack of any whistle coming from the vent, but apparently the customer had the tank disconnected and removed, and didn't tell their fuel supplier. Delivery truck showed up on the regular schedule, and pumped more than 550 gallons into the basement, before realizing something must be wrong. They had a long few days of cleaning up the initial mess, before remediation could even begin.
 
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same thing happened to a customer of mine except his tank was still there and a bee built a nest inside the whistler pipe but the oil driver he still kept pumping blew the side off the tank and that allowed 300 gallons to flow to the dirt floor. the lady on the 2nd floor was waiting for the bus across the street and seen the thick black smoke billowing from the chimney and ran home to get her husband and kids out of the house and anyone left in the 4 family. the oil burner that was running shut down but the lake of oil was seeping into the hot oil chamber and was smokey because of not being sprayed. when all was said and done the oil company's insurance paid to have the dirt floor removed down to ten feet and the foundation walls were replaced from the footing up 4 feet. and because of the smell of number 2 heating oil the wood floors had to be replaced on the 1st floor in 1 apartment and the soft furniture on both 1st floor apartment and clothes had to be replaced. this was 25 to 30 years ago and back then cost the oil company's insurance $300,000. now because i know the oil company's owner i found out the the same guy did it again the following week. this house was built in 1805 the owners apartment still had the original fireplace and cast iron arm with a pot hanging for cooking. oh ya and almost forgot they had to change 2 gas boilers and 2 water heaters
 
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Leaving old tanks and filler in place is not unusual. I have run into a few. My brother switched to gas at one point and left the tank full of oil for at least ten years complete with the fill pipes. I think he had an underfloor line so at any point it could have rotted out and started dumping the oil. The last firm I bought oil from has a red tag with customer number on the filler pipe and the drivers are not supposed to fill any tank without the tag. The problem is these days is there is shortage of drivers and few folks can afford a 250 gallons of oil in one fill up, during a cold snap those drivers are driving seven days a week 12 plus hours a day making small fills. A portion of them are in the dark and in the snow. Cities and towns do not enforce regulations to have an easy to read visible house number marking so its easy for a tired driver being pounded on to crank out the deliveries to see a fill and hook up to it. I have known several folks who have gotten free fills of oil from dealers that go confused and filled the wrong tank.
 
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Leaving old tanks and filler in place is not unusual. I have run into a few. My brother switched to gas at one point and left the tank full of oil for at least ten years complete with the fill pipes. I think he had an underfloor line so at any point it could have rotted out and started dumping the oil. The last firm I bought oil from has a red tag with customer number on the filler pipe and the drivers are not supposed to fill any tank without the tag. The problem is these days is there is shortage of drivers and few folks can afford a 250 gallons of oil in one fill up, during a cold snap those drivers are driving seven days a week 12 plus hours a day making small fills. A portion of them are in the dark and in the snow. Cities and towns do not enforce regulations to have an easy to read visible house number marking so its easy for a tired driver being pounded on to crank out the deliveries to see a fill and hook up to it. I have known several folks who have gotten free fills of oil from dealers that go confused and filled the wrong tank.
When our tanks were out of commission and we were awaiting a new one I got some good advice. Notify the oil company and block off the fill pipes for these reasons.
 
The problem is these days is there is shortage of drivers and few folks can afford a 250 gallons of oil in one fill up, during a cold snap those drivers are driving seven days a week 12 plus hours a day making small fills.
Piss-poor management, in that case. It's a miracle the delivery company is in business.

Back when I was too poor to write a single check for an oil fill, I was on an installment program, so I could spread the cost out over the course of the year. Even those folks getting small fill-ups are using what they're using, the delivery co. is just absorbing all that extra cost of driving around to put a few gallons at time into each tank. They would do well to force those customers onto installment plans, so they could make one trip and do one fill-up, in place of five trips for five fill-ups.
 
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or charge per trip in a 30 day period
I like the idea, but this plan would hurt legit users getting multiple full fill-ups inside 30 days. A surcharge on partial fills would be more appropriate.
 
We had a min fill. You could not call up and get 100$ worth
the min at the time was 200$ Mind you this was years ago (15)
we have been off oil for 6 years
 
Installment plans only work if the owners and tenants have a credit rating. Disproportionally, the poor are the ones that are heating old poorly insulated places. The elderly who depend on only Social Security, tend to live from check to check and they typically have a choice of food, drugs or heat so laying out a $1000 bucks for a tank fill just will not happen. In many cases their credit rating is poor, the days of small family oil firms is rapidly going away where the owner was local and had some flexibility. They are being scooped up by regional firms that are far less flexible. Most have minimum delivery with surcharges on smaller deliveries. Many do a credit check even for installment plans as they do not want the hassle. I have seen folks who buy a couple of 5 gallon cans of offroad diesel when they can afford to rather than pay the surcharges for small deliveries and hope they dont need a service call to get the furnace running when it runs out.
 
Bad situation, but I will still argue the installment plan is the ultimate solution, rather than cash payments on small deliveries.

1. Cash for small deliveries, with a surcharge for partial fill, is net negative value to customer. They are ultimately paying more for what they are getting, and they already have budget issues.

2. Cash for small deliveries still puts more trucks and more pollution on the road.

3. Forcing people to haul their own cans of off-road diesel leaves them up Schitt's creek when they have an equipment issue. They would ultimately be better off, for lower net cost and safety, on a service plan.

Fixing the financing constraints around issuing installment plans, with regulation or public or private assistance if necessary, would be a better solution for everyone involved. Unfortunately, doing that without a few select well-connected providers reaping most of the benefit, is where municipalities usually fail.
 
"subscription" oil deliveries here are based on what the oil company estimates you use based on history and weather, and *they* decide when they top you up. The one year I did this, I'd only call them if my tank would get low. (Which never happened.)
So if *they* make 12 hr days of small deliveries, it is indeed piss poor management.
On the other hand, companies that do "on call" deliveries (without a subscription), give lower prices per gallon for larger deliveries. That's what I do when I need oil: call my company and tell them to fill the tank (i.e. 150-200 gallon deliveries). Depending on the ratio of such customers with larger deliveries, and subscription ones with smaller ones, they can add one or two smaller ones on a route with larger ones. It's like adding 1" sticks to a firebox with splits to utilize the full volume.

My view, it's the oil delivery companies that make the choice for small deliveries. I don't care then.
And if it's the customer calling for 25 gallons, they already cahrge more per gallon for such deliveries - precisely for the reason of higher cost.

So I don't see the issue.
 
So I don't see the issue.
The issue was people calling the oil delivery company for repeated small deliveries, because they couldn't afford a full fill. It's been awhile since I was on a full installment plan with service contract, but when I was, I paid the same price for oil (no premium), and also got a huge discount on service, and also got free coverage for any system failures within 12 months of last service. It was a good deal.
 
Wow! Interesting - thanks for sharing.

I think most CO sensors are just looking for something they can oxidize. Normal air being oxygen and nitrogen, oxidation is generally a 'no', so the sensor sits there quietly. If anything like CO comes along, then CO + O2 > CO2 is possible and the sensor is tripped.

If it were a precision scientific sensor, then there might be other physical or software additions to screen out false positives. But as you see, generally, anything 'able to oxidize' in your home air is bad... natural gas, hydrocarbon vapors from gasoline, diesel fuel, fuel oil, paint thinner, etc. It's cheaper to leave the sensor with a lot of co-sensitivity and in home application, not necessarily a bad thing!

Guess the other key thing - if you see a leak, be very careful in your plan to deal with it. Knew a guy that noticed a small pinhole leak and thought he'd 'tighten the fitting up a bit'. Well, the rusted, paper thin metal totally shredded at a turn of the wrench and turned a few drops into a full on gush! Luckily, this was a coolant system, so a big mess of rusty water was the worst of it. But I can imagine the same with fuel oil in a basement - that would be bad!!
 
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No, CO sensors work either by a gel that changes color upon absorbing CO, a transistor whose channel conductivity changes upon CO adsoption, or a solution whose conductivity changes upon CO entering the solution.

They are *not* (necessarily) sensitive to other combustibles in the air. Don't make that mistake thinking you're covered for something (e.g. propane) when you're not.
 
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I like the idea, but this plan would hurt legit users getting multiple full fill-ups inside 30 days. A surcharge on partial fills would be more appropriate.
your idea is a better one. but if they are using that much they should get two tanks. i have customers that have two 330 gallon tanks. big houses. one was getting a fill every week or she would run out so the plumber install two oil burners and i wired them on a computer so most of the time it was running one unless it needed more
 
Years ago a friend had an old camp converted to a year round place with an outdoor oil tank. They were painting the house and someone leaned against it. One of the legs snapped off at the threads and it fell down and broke off the outlet pipe at the tank. They initially used a finger and then wooden stick to slow down the flow and then had to empty it out. All they had was plastic trash cans so they stuck garbage bags in them and hand pumped the tank with hand bilge pump from a boat. They had abotu 150 gallons in there and it realy did not make much of mess.

I think Maine now requires that outdoor tanks have steel shields over the outlet pipe, valve and filter to keep those lines from being broken off by ice or snow.