Minnesota Administrative Rules

7151.6600 CORROSION PROTECTION.

Subpart 1.

General.

Owners and operators shall apply corrosion protection to all steel tanks and tank systems except as otherwise provided in subpart 5.

Subp. 2.

Tanks.

The floor of an existing steel aboveground storage tank must be protected from external corrosion using one or more of the following methods:

A.

the tank is elevated so that the underside of the tank's floor is not in contact with any surface other than the supports;

B.

the tank rests on a continuous concrete slab that is designed to prevent water from accumulating under the tank floor;

C.

the tank is double walled;

D.

the tank is double-bottomed with:

(1)

a vacuum pulled on the interstitial space; or

(2)

a cathodic protection system installed in the interstitial space;

E.

the tank floor is:

(1)

cathodically protected; and

(2)

internally lined in accordance with American Petroleum Institute Standard 652;

F.

the tank floor is:

(1)

cathodically protected; and

(2)

internally inspected in accordance with American Petroleum Institute Standard 653 prior to November 1, 2003, and thereafter as indicated by the results of the inspection; or

G.

the tank floor is:

(1)

internally lined in accordance with American Petroleum Institute Standard 652; and

(2)

internally inspected in accordance with American Petroleum Institute Standard 653.

Subp. 3.

Lines.

An existing steel line must be protected from external corrosion using one or more of the following methods:

A.

the line is not in contact with soil;

B.

the underground line is cathodically protected; or

C.

the underground line is double walled.

Subp. 4.

Design criteria.

Cathodic protection of existing steel tanks and lines must be designed by a corrosion expert in accordance with American Petroleum Institute Standards 651 and 1632, as applicable.

Subp. 5.

Exclusions.

A secondary containment area for tanks or tank systems which complies with the requirements of part 7151.5400, subparts 1, 2, 3, items B to I, and 4, is excluded from the requirements of this part.

Subp. 6.

Timing of compliance.

Owners and operators shall comply with this part effective November 1, 2003.

Statutory Authority:

MS s 115.03

History:

23 SR 883; 25 SR 556

Published Electronically:

October 2, 2007