N.M. Admin. Code § 20.5.108.803

Current through Register Vol. 35, No. 23, December 10, 2024

Section 20.5.108.803 - MANUAL TANK GAUGING REQUIREMENTS FOR USTS

A. Manual tank gauging:

(1) may be used as the sole method of release detection for regulated underground tanks of 550 gallons or less nominal capacity and tanks with a nominal capacity of 551 to 1,000 gallons that meet the tank diameter of 48 inches or 64 inches for the life of these tanks;

(2) may be used as a method of release detection for regulated underground tanks with a nominal capacity of 551 to 1,000 gallons, with a diameter other than either 48 inches or 64 inches, for 10 years after installation in conjunction with periodic tank tightness testing in accordance with 20.5.108.802 NMAC and 20.5.108.804 NMAC;

(3) may be used as a method of release detection for regulated underground tanks with a nominal capacity of 1,001 to 2,000 gallons with any diameter for 10 years after installation in conjunction with periodic tank tightness testing in accordance with 20.5.108.802 NMAC and 20.5.108.804 NMAC;

(4) shall not be used after the 10^th year of the installation for tanks described in Paragraphs (2) and (3) of this subsection; after the 10^th year, owners and operators shall change to a method described in 20.5.108.805 NMAC through 20.5.108.809 NMAC; and

(5) shall not be used to meet the requirements of this part for tanks of greater than 2,000 gallons nominal capacity.

B. Owners and operators of underground storage tanks who use manual tank gauging as release detection shall ensure the following:

(1) tank liquid level measurements are taken at the beginning and ending of a period of at least 36 hours during which no liquid is added to or removed from the tank;

(2) level measurements are based on an average of two consecutive stick readings at both the beginning and ending of the period;

(3) the equipment used is capable of measuring the level of product over the full range of the tank's height to the nearest one-eighth of an inch;

(4) a suspected release is reported in accordance with the requirements of 20.5.118 NMAC if the variation between beginning and ending measurements exceeds any of the weekly or monthly standards as follows:

(a) underground storage tank with a nominal capacity of 550 gallons or less, with a minimum test duration of 36 hours, where the weekly standard for one test exceeds 10 gallons, or the monthly standard for a four-test average exceeds five gallons;

(b) underground storage tank with a nominal capacity of 551 gallons through 1,000 gallons with a tank diameter of 64 inches and a minimum test duration of 44 hours, where the weekly standard for one test exceeds nine gallons or the monthly standard for a four-test average exceeds four gallons;

(c) underground storage tank with a nominal capacity of 551 gallons through 1,000 gallons with a tank diameter of 48 inches and a minimum test duration of 58 hours, where the weekly standard for one test exceeds 12 gallons or the monthly standard for a four-test average exceeds six gallons;

(d) underground storage tank with a nominal capacity of 551 gallons through 1,000 gallons, with a minimum test duration of 36 hours, where the weekly standard for one test exceeds 13 gallons or the monthly standard for a four-test average exceeds seven gallons;

(e) underground storage tank with a nominal capacity of 1,001 gallons through 2,000 gallons, with a minimum test duration of 36 hours, where the weekly standard for one test exceeds 26 gallons or the monthly standard for a four-test average exceeds 13 gallons.

C. At least annually, owners and operators shall check the operability and serviceability of any measuring device or equipment used for manual tank gauging in accordance with Subsection A of 20.5.108.800 NMAC.

D. Measurements and results of each monthly monitoring period shall be maintained in accordance with the recordkeeping requirements in 20.5.108.815 NMAC and shall be provided to the department upon request.

N.M. Admin. Code § 20.5.108.803

Adopted by New Mexico Register, Volume XXIX, Issue 14, July 24, 2018, eff. 7/24/2018