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Petroleum Bulk Storage Underground Tank Tightness Testing FAQ's

NOTE: This information is intended to provide facility owners and operators answers to commonly asked questions. Facility owners should obtain a copy of the state Petroleum Bulk Storage (PBS) regulations from their local DEC Regional Office, and read them carefully and in their entirety. Facility owners are responsible for complying with all of the PBS regulations.

1. What NYS law requires tank tightness testing?

In an effort to prevent leaks and spills, the New York State Legislature passed the Petroleum Bulk Storage (PBS) Law (Article 17, Title 10 of the Environmental Conservation Law) requiring DEC to develop and enforce a State code for storage and handling of petroleum. The resulting regulations are Parts 612, 613, & 614 of Title 6 of the New York State Code of Rules and Regulations (6 NYCRR Parts 612, 613, & 614). Part 612 covers registration and notification requirements. Among other things, Part 613 requires owners to periodically test underground systems, inspect aboveground storage systems and report test results to DEC. Any equipment found leaking must be repaired or replaced in accordance with Part 614, the standards for new or substantially modified facilities, or closed in accordance with section 613.9.

2. Which tanks must be tested?

Only underground PBS tanks must be tested for tightness. Individual underground tanks and connecting piping systems that are larger than 1,100 gallons and that store fuels or motor lubricants such as gasoline, heating oil, heavy residual fuel oils (except #5 and #6 fuel oil), kerosene or reprocessed waste oil used as a fuel or lubricant, must be tested periodically. These include manifolded systems (tanks which are interconnected by piping) where combined capacity of the manifolded tanks and piping exceeds 1,100 gallons.

Tanks in subterranean vaults or basements which cannot be visually inspected are considered underground tanks and must be tested. However, tanks in subterranean vaults which are accessible for visual inspection or wrapped tanks in New York City that have weep holes that can be visually inspected for leakage, are considered aboveground, and therefore do not have to be tested. However, these aboveground tanks must be inspected. (See section 613.6 for more information.)

No periodic testing is required for:

  • Tanks storing #5 or #6 fuel oil;
  • Systems consisting of corrosion-resistant* tanks and piping, with leak monitoring; and
  • New systems installed in compliance with the standards for new construction (6NYCRR Part 614).

* Corrosion-resistant systems include those constructed of fiberglass-reinforced-plastic (FRP); steel protected by fiberglass (FRP) coatings, or steel that were installed with sacrificial anodes, or impressed current systems (cathodically protected). Steel tank and piping systems that have been retrofitted with cathodic protection or an interior lining are not considered corrosion resistant and must be tested whether or not any other leak detection system is in use on the tank system.

3. What should I do if I think the notice has been sent in error and that I am not required to test my tank(s)?

If you believe that your tank(s) is not required to be tested, you must call the regional office and speak with a member of the PBS staff. They will guide you on the requirements for your tank system. If you ignore this tank testing notice, follow-up enforcement will occur.

4. When must tanks be tested?

Unprotected tanks, such as bare steel, asphalt coated, or painted steel tanks, must be tested when 10 years old. Corrosion-resistant tanks, such as fiberglass or cathodically protected tanks, must be tested when 15 years old. All tanks which require testing must be retested every five (5) years from the date of the last test. Tanks and pipes which were installed corrosion-resistant and are equipped with leak monitoring systems do not require testing but do require periodic monitoring of the leak detection system and inventory monitoring.

Initial tests for tanks of unknown age and for tanks whose test was due at the start of the Petroleum Bulk Storage Program, were due for testing at the end of the two-year "phase-in" period, which was December 27, 1987. Tanks must now be tested on or before the due date which is listed on the five (5)-year registration certificate issued by DEC. (Note: Due dates might not appear on the certificate for manifolded tanks where individual tanks are less than 1,101 gallons: however, if the combined capacity is over 1,100 gallons, these tanks must be tested.)

When the ownership of a PBS facility is transferred, the new owner should submit the registration application along with any test results for tanks tested by the previous owner within the past five (5) years, in accordance with section 613.5.

Owners who fail to test tanks properly before the due date may be subject to civil, administrative and criminal penalties.

5. Who is responsible for testing?

Under the law, the tank owner (not operator) are responsible for having tanks and piping tested periodically by a qualified technician. However, an operator may be held liable for penalties for operating a tank or tanks which have not been properly tested. In New York City, the City Fire Department must also be contacted prior to testing motor fuel tanks and piping. Operators of regulated facilities should remind owners of these testing requirements.

6. What is a tightness test?

A tightness test is a means of determining whether an underground storage tank and its piping system are leaking. DEC requires using a test that can detect a tank or piping leak (leak threshold) of 0.05 gallons per hour (gph) or smaller. The test(s) used must detect leaks from the entire tank system - liquid portion of the tank, the vapor space above the product, and all underground product piping. There are four test types or combination of test types that can be used to accomplish this:

  • A volumetric overfill test (a separate product piping test may also be needed depending on the tank system configuration);
  • A volumetric underfill test in conjunction with a non-volumetric ullage (vapor space) test and product piping test;
  • A non-volumetric vacuum test (a separate product piping test may also be needed depending on the tank system configuration); and
  • A non-volumetric tracer test.

There are many variables which can affect the ability of each of these tests to detect a leak. Volumetric tests require tanks be taken out-of-service for a period of time so that the product in the tank has a chance to stabilize. One of the common variables for almost all test methods is the need to know if groundwater is around the tank. In order to compensate for the effect of groundwater around the tank, it's depth must be determined on site by using either a well or well point (without this information on the test report, the test is invalid).

Because some tests compensate for variables better than others, DEC has compiled a list of tank tests which meet the requirements set forth in the regulations and which give results that are acceptable to the Department. A copy of this list is available from the DEC Regional Offices. A list of all leak detection methods, including tank tightness tests, with a specification page that indicates how each leak detection method must be used is available at the web site for the National Work Group on Leak Detection Evaluations (See "Links Leaving DEC's Website" on the right menu of this page). Tests must be conducted in accordance with this specification in order to be acceptable. [When looking at the website, look under "Method Index" and then one of the following categories: volumetric overfill, volumetric underfill, non-volumetric tank tightness test method (tracer), non-volumetric tank tightness test method (ullage), non-volumetric tank tightness test method (vacuum), or line tightness test method.]

There may be instances, as with underground tanks larger than 50,000 gallons, where it is technically impossible to perform a tank test with a leak threshold of 0.05 gph. In such cases, the owner must perform an alternative test or inspection which is acceptable to the Department. You must contact the regional office for further information.

7. Who is a qualified tester and where do I find one?

Each test manufacturer trains and certifies technicians who performs that test. Each technician will have a certificate that indicates that they have been properly trained as well as an expiration date for that certification. The certification number for the technician performing the test must be included on the test report. Companies that provide tank testing services can be found in the telephone book, or you might get a referral from your petroleum supplier. In some cases, the regional office may also maintain a list of companies that provide tank testing services. If you have any questions about a technician, call the test manufacturer. The manufacturer's phone number is on the list found at the website for the National Work Group on Leak Detection Evaluations (See "Links Leaving DEC's Website" on the right menu of this page).

8. How are test results reported?

The test report must include the test results, calculations, how groundwater was determined and all information required in 6 NYCRR subparagraph 613.5(a)(4)(ii). This test report must be sent to the Regional Office. One copy of the report must be kept on file by the tank owner for at least five (5) years.

Test results must be submitted to DEC by the owner or the test technician within thirty (30) days after the test is performed.

9. What if my tank fails a tightness test?

If the tightness test indicates that the storage system (tank and associated piping) is leaking, the leak must be reported to the State Spill Hotline within two (2) hours by any person with knowledge of the leak. The Toll-free State Spill Hotline is 1-800-457-7362 from within New York State and 518-457-7362 when calling from outside the state. The next step is to quickly determine the source of the leak, whether tank or piping. Once the source is isolated, the tank must be promptly emptied, and the leaking tank or pipe taken out-of-service and repaired or replaced in accordance with the PBS regulations.

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