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OIL STORAGE TANKS
ABANDONING OIL TANKS
AFUE DEFINITION, RATINGS
AGE of OIL TANK
ANODES & DIP TUBES on WATER HEATERS
BIOGAS PRODUCTION & USE
BURIED OIL TANK ADVICE
BURIED OIL TANKS, FINDING
COMBUSTION PRODUCTS & IAQ
DEFINITION of Heating & Cooling Terms
DIAGNOSE & FIX HEATING PROBLEMS-BOILER
DIAGNOSE & FIX HEATING PROBLEMS-FURNACE
DIRECT VENTS / SIDE WALL VENTS
DIRECTORY of OIL TANK EXPERTS
FILTERS, OIL on HEATING EQUIPMENT
FIRE SAFETY CONTROLS
FLAME COLOR, BLUE vs YELLOW COMBUSTION
FLOATING UP OIL STORAGE or SEPTIC TANKS
FLOODED HEATING EQUIPMENT REPAIR
FLOODED WATER HEATER REPAIR
FUEL OIL TYPES & CHARACTERISTICS
FUEL UNIT, HEATING OIL PUMPS
GALVANIC SCALE & METAL CORROSION
GAUGES ON HEATING EQUIPMENT
HEAT LOSS in BUILDINGS
HEAT TAPES, Heat, Insulation prevent Freeze-Up
HEATING COST FUEL & BTU Cost Table
HEATING COST SAVINGS METHODS
HEATING OIL CLOUD WAX GEL POINT
HEATING OIL EXPOSURE HAZARDS, LIMITS
HEATING OIL - OLD, USEABLE?
HEATING OIL PIPING TROUBLES
HEATING OIL SLUDGE
HEATING OIL TANKS
HEATING OIL TYPES & PROPERTIES
HEATING OIL USAGE RATE
HEATING SYSTEM NOISES
HOME BUYERS GUIDE TO OIL TANKS
HOT WATER HEATERS
NO HEAT - BOILER
NO HEAT - FURNACE
NOISE CONTROL for HEATING SYSTEMS
NOISES COMING FROM WATER HEATER
ODORS & SMELLS DIAGNOSIS & CURE
ODORS FROM HEATING SYSTEMS
OIL BURNER FUEL UNIT
OIL BURNER INSPECTION & REPAIR
OIL BURNER NOISE SMOKE ODORS
OIL BURNER SOOT & PUFFBACKS
OIL FILTERS on HEATING EQUIPMENT
OIL FILTER MISSING
OIL FUEL TYPES & CHARACTERISTICS
OIL LINE CLOGGING FIX
OIL LINE QUICK STOP VALVES
OIL LINE SAFETY VALVES
OIL ODORS, LEAKY OIL TANK PIPING
OIL PUMP FUEL UNIT
OIL SPILL CLEANUP / PREVENTION
SOOT on OIL FIRED HEATING EQUIPMENT
STAIN DIAGNOSIS on BUILDING INTERIORS
Oil Storage Tank & Piping Failure or Leak Rates - Oil Tank Leak Probability as a Function of Tank Age, Location, Condition, Soil Conditions and Other Factors: this document discusses oil tank leaks or oil storage tank failure rates as a function of oil storage tank age, the oil tank location (indoors, outdoors above ground, buried outdoors, oil tank condition, and for buried oil tanks, the soil conditions. We point out that studies show that significantly more leaks occur in the oil piping system than in the tanks themselves.
Steel oil storage tanks, especially if buried and 15-20 years old or older are at a significant risk causing costly oil leaks and risking environmental damage. Since significant costs are involved in oil tank replacement and in cleaning up oil-contaminated soils or building materials, testing and inspection are appropriate when one is buying or evaluating a property where tanks are installed.
Green links show where you are. © Copyright 2013 InspectAPedia.com, All Rights Reserved. Author Daniel Friedman.
Oil Tank Leak Rate in U.S. EPA Study performed in New York
A study of 500 underground fuel storage tanks was completed for the U.S. EPA and studied tanks on Long Island in New York in 1988. See "[Fuel Storage] Tank Corrosion Study", U.S. EPA report on gasoline and oil tank corrosion, November 1988. Of those 500 storage tanks about half were used for gasoline storage and about one fourth were used for home heating oil storage. But significantly the underground storage tank leak rate did not depend on what fuel was being stored.
The major conclusions of the New York / EPA fuel storage tank leak study were summarized as follows:
Petroleum Product Storage Tank Leak Rate in Maryland, 1986 Study finds 40% Leak Rate of which Oil Piping Caused 82% of all leaks
This study included not just heating oil storage tanks but also gasoline tanks, waste oil tanks, and emergency generator tanks (kerosene or diesel fuel). The finding that more heating oil storage system leaks occurred in the oil piping than in tanks themselves is consistent with the New England study (reported above) that found roughly twice as many leaks in the oil piping system than in oil tanks.
Significantly, Heck's study indicated that age was not a determining factor in the occurrence of leaks at oil & gasoline tanks in her study, an observation that makes sense given the high percentage of leaks traced not to the tank but to piping problems.
Also significant, Heck's study points out that among petroleum product storage tank leak failures there were two distinct categories of oil leak types & locations that are consistent with our own field experience:
Petroleum product storage tank leaks at the top of tanks occurred at
News media reportage of oil tank leaks has suggested significant contamination issues in some parts of the U.S., particularly where the aquifer is common and prone to widespread movement of contaminants leaked onto or into the ground.
"Almost 10,000 gasoline and oil spills, some of them more than a decade old, are contaminating the underground aquifers that supply drinking water to Long Island and southeast Queens even as state environmental officials aren't enforcing laws that call for complete cleanups."
The article continues to site gas stations as a buried leaky petroleum product storage tank primary offender, and warns that private wells are at particular risk of dangerous contamination.
[Newsday, Dan Fagin, August 23, 1998, http://www.junkscience.com/news3/nylirbca.htm]
We have indeed had occasional reports of private wells and water supplies being contaminated by leaky gas station fuel tanks, and one instance was reported [privately] of a private well and local ground water contaminated by an owner who dumped waste oil into what s/he thought was an "abandoned water well". Never ever use an abandoned well or even a septic system to dispose of unwanted oils or other chemicals.
Real Estate Publications, while reluctant to scare home owners and buyers by aggressive reporting on leaky oil tanks (which can involve a very large cleanup expense), also cite the concern for leaking oil tanks.
"Statistics indicate as many as 25% of all underground storage tanks (USTs) may now be leaking. These underground tanks may hold oil or gas but can most frequently be found at homes heated with oil. Over time, there is a tendency for these older tanks to corrode and leak their contents into the ground and possibly into the ground water. Because of the great expense involved in cleaning up the contamination caused by leaking tanks, it behooves those that have older underground tanks, to have them or the soil tested."
[This article, at a website published by a Maryland real estate firm, has appeared on numerous websites. The original source and basis of statistics were not cited in the article. http://www.soldbyteresa.com/information_center/article_archive/buried_oil_tanks.dwt 4/27/06]
European studies of oil tank leak rates have confirmed that the risk of buried (steel) oil tank leaks increase significantly when tanks are about 20 years old. [Norway Clean Oslo Fjord project and references cited above.] However leaks can occur even when a tank is brand new if the tank is damaged during installation or if its piping is not correctly installed.
Smaller leaks or spills around oil tanks may occur during tank fill operations.
For an interesting non-residential study of oil tank leaks, see
History, 200 Area Tank Farms. See
Survey, Nuclear, Westinghouse Hanford to participate in an interesting
Fuel or Heating Oil Storage Tank Failure Mechanisms
The causes of oil tank leaks or tank failures are discussed briefly at OIL TANK FAILURE MECHANISMS - "Buried fuel oil tanks, oil or gas, basic advice for home owners and home buyers, home inspection report language", which lists the most-common causes of oil leaks in above ground or buried oil storage tanks.
OIL TANK FAILURE CAUSES provides the details of the common mechanisms leading to buried or above ground oil storage tank leaks and failure.
In New England, for a two year period [1984-5] oil heat customers were surveyed by the oil heat industry, disclosing that oil tank piping leak rates back in 1984-1985 were 2.5 fuel line leaks per 1000 oil heating customers. This was 1 1/2 times as many oil piping leaks as buried oil tank leaks during that period. [Keep in mind that by 2010 the oil tank leak data would be different, both because the older oil tanks would be at a higher risk of leakage, and because at the same time, by 2010 many older oil storage tanks would have been replaced.
These heating oil tank leak rates and oil tank fuel line leak rates were reported in Fuel Oil and Oil Heat magazine, August 1985 p.18. We do not have similar data for buried LP gas storage tanks in residential application.
Frequently Asked Questions (FAQs) about Oil Tank Failures & Failure Rates
Question: What is the oil storage tank failure rate for specific countries?
Please do you have any Material on Tank Storage / Failure rates for Nigeria. Many Thanks. [Anon]
Reply: here are some questions to ask, data to gather, to form an opinion about probable risk of oil tank leaks or failures in a given geographic area
A competent onsite inspection by an expert usually finds additional clues that help accurately diagnose a problem with failing oiltanks in a specific geographic area. That said, sorry, no we don't have information specifically for your country. However if we (or you) can dig up some oil tank installation information we could probably make a reasonable and general statement about relative risk levels of leaks. For example, you'd need to collect guesses or actual data on
- the total number of tanks installed indoors, outdoors above ground, outdoors buried
There are also some simple inspections and tests that can be peformed on existing tanks as spot checks or for representative samples.
Questions & answers or comments about oil tank failure rates, leak data, and the causes of oil storage tank failures.
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Technical Reviewers & References
Related Topics, found near the top of this page suggest articles closely related to this one.
Five hundred plain steel [underground fuel storage] tanks plus twelve corrosion protected [under ground oil] storage tanks were removed from the ground over an eighteen month period in Suffolk County, Long Island, New York. The oil tanks were examined carefully before disposal to gather statistics on the nature and extent of steel oil storage tank corrosion that had attacked them. Information was gathered on the number, type, location, and size of oil storage tank perforations [oil storage tank leak points] the general interior and exterior corrosion condition of the oil storage tank, soil, backfill, and groundwater conditions; the presence of leaked product [heating oil], and oil storage tank statistics such as tank volume, steel plate thickness, location, product [type of heating oil stored], tank age, etc. The statistics were compiled and compared, observations made, and conclusions developed. The major conclusions [were] summarized as follows:
In September 1986, a precision tank testing program was started to bring a major Maryland utility into compliance with the State of Maryland Oil Spill Control Regulations regarding underground storage tanks. This program involved the testing of over 240 tanks ranging in size from 300 gallons to 1,500 gallons located throughout the entire state of Maryland.
Analyses of the testing results revealed that 40% of the systems tested leaked. Piping leaks caused 82% of the testing failures and tank leaks caused the remaining 18%. Tank systems located in urban areas experienced a 50% testing failure rate, while tank systems located in rural areas experienced only a 25% failure rate. Leaks in tank systems in urban areas appear to be the result of structural loading and corrosion, affects [effects] absent in rural areas. The age, capacity, and usage of the tanks did not have a role in causing leaks either in the piping or the tank.