D.C. Mun. Regs. tit. 20, r. 20-6101

Current through Register Vol. 72, No. 2, January 10, 2025

Rule 20-6101 - PERMANENT CLOSURE AND CHANGE-IN-SERVICE

6101.1

Each responsible party permanently closing an UST or changing the use of the UST to storage of a non-regulated substance (a change- in-service) shall comply with the requirements of this section.

6101.2

Not less than two (2) weeks before a permanent closure or a change- in-service of an UST, the responsible party shall notify the Department by submitting an UST activity notification form, which is available on the Department's website at https://doee.dc.gov/page/ust-forms- guidance-and-public-documents. Notice is not required if such action is taken pursuant to a corrective action plan approved by the Department.

6101.3

The responsible party may use the following codes of practice, or an alternative industry standard or code of practice approved by the Department in accordance with § 5506, to comply with the cleaning and closure requirements of this section:

(a) American Petroleum Institute Recommended Practice RP 1604, "Closure of Underground Petroleum Storage Tanks";

(b) American Petroleum Institute Standard 2015, "Safe Entry and Cleaning of Petroleum Storage Tanks, Planning and Managing Tank Entry From Decommissioning Through Recommissioning";

(c) American Petroleum Institute Recommended Practice RP 2016, "Guidelines and Procedures for Entering and Cleaning Petroleum Storage Tanks"; or

(d) National Fire Protection Association Standard 326, "Standard for the Safeguarding of Tanks and Containers for Entry, Cleaning, or Repair."

6101.4

Before a change- in-service, the responsible party shall empty and clean the tank by removing and properly disposing of all liquid and all accumulated sludge in compliance with applicable laws and regulations.

6101.5

Before an UST system is removed from the ground, the responsible party shall empty the UST system, if it is not already emptied during the temporary closure period, and clean it by removing and properly disposing of all liquids and all accumulated sludge in compliance with applicable laws and regulations.

6101.6

For each UST system that is to be closed permanently, the responsible party shall remove the tank from the ground, unless a tank removal variance is granted by the Department pursuant to § 6101.7.

6101.7

A responsible party may apply for a tank removal variance (for closure-in-place) by submitting the following documents:

(a) A written request for a tank removal variance;

(b) Written certification of the existence of the conditions stated in § 6101.8, with supporting documentation, from a professional engineer licensed in the District; and

(c) A tank interior inspection report or the results of analysis of soil borings taken from soil adjacent to t he tank if the interior cannot be inspected.

6101.8

The Department may grant a tank removal variance if removal of the tank is likely to cause substantial structural damage to buildings or other improvements on the property, or there are other circumstances that make removal of the tank infeasible.

6101.9

If the Department grants a variance, the responsible party shall ensure that the tank is emptied, cleaned, and filled with an inert solid material, such as cement, or another material approved by the Department in accordance with § 5500.5.

6101.10

Before a change- in-service or permanent closure of an UST, the responsible party shall conduct a closure assessment of the excavation zone to test for the presence of a release in the areas around the UST system where contamination is most likely to be present.

6101.11

In selecting sample types, sample locations, and analytical methods for the closure assessment, the responsible party shall consider the method of closure, the nature of the stored substance, the type of backfill, the depth to groundwater, and other factors appropriate for identifying the presence of a release. The responsible party shall comply with any directives that may be issued by a Department inspector regarding the number of samples and the location of soil borings or groundwater monitoring wells.

6101.12

If contaminated soil, contaminated groundwater, free product, or vapor are discovered during the closure assessment, or by any other manner, the responsible party shall begin corrective action in accordance with the applicable provisions of Chapter 62, except as provided in § 6101.15.

6101.13

Soil excavated during removal or corrective action shall be handled as follows:

(a) Soil that has been tested and that does not exceed Tier 0, or Tier 1 for total petroleum hydrocarbon gasoline range organics (TPH-GRO) on sites with current or future residential use, screening levels may be placed on the site and shall be covered with plastic as a soil erosion control measure until backfilled or permanently stabilized;

(b) Soil that exceeds Tier 0, or Tier 1 for TPH-GRO on sites with current or future residential use, standards shall be treated or properly disposed of at an approved disposal location;

(c) When approved by the Department, excavated soil may be stockpiled at the excavation site for no more than ten (10) business days pending completion of testing and analysis for contaminants; and

(d) Soil shall not be placed on another property unless specifically approved by the Department in accordance with § 5500.5.

6101.14

Soil that exceeds Tier 0, or Tier 1 for TPH-GRO on sites with current or future residential use, risk-based screening levels shall not be returned to the excavation pit or used on the site without treatment.

6101.15

If a release of a regulated substance has occurred, the responsible party shall evaluate the excavation zone as follows:

(a) Remove contaminated soils to a depth of at least five feet (5 ft) below the tank bottom and a width of at least five feet (5 ft) from the sides of the tank;

(b) Assess the excavation zone for evidence of contamination (such as free product or vapors requiring initial response, initial abatement actions, or free product removal pursuant to §§ 6203 or 6204) and sample the remaining soil for chemicals of concern;

(c) If the levels of chemicals of concern in the remaining soil exceed the Tier 1 screening levels, take at least one (1) groundwater sample to determine whether any chemicals of concern in groundwater exceed the Tier 1 screening levels;

(d) Remove additional soil from the excavation zone as necessary until the levels of chemicals of concern in the remaining soil are below Tier 1 screening levels, the groundwater does not exceed the Tier 1 screening levels, and there is no other evidence of contamination; and

(e) If the criteria set forth in paragraph (d) of this subsection cannot be met, begin corrective action in accordance with the applicable provisions of Chapter 62.

6101.16

Within thirty (30) days after completing the permanent closure or change- in-service, the responsible party shall submit to the Department a closure assessment report in a format provided by the Department and submit an amended UST facility notification form, both of which are available on the Department's website at https://doee.dc.gov/page/ust- forms-guidance-and-public-documents. The Department may open a LUST case and require additional site assessment and cleanup according to Chapter 62.

D.C. Mun. Regs. tit. 20, r. 20-6101

Final Rulemaking published at 40 DCR 7835, 7878 (November 12, 1993); as amended by Final Rulemaking published at 46 DCR 7699 (October 1, 1999); amended by Final Rulemaking published at 67 DCR 1778 (2/21/2020)