The Developments of National Significance (Specified Criteria and Prescribed Secondary Consents) (Wales) Regulations 2016

Underground gas storage facilities

5.—(1) Development relating to underground gas storage facilities is within regulation 3(1)(b) only if the development is within paragraphs (2), (3), (4) or (6) of this regulation.

(2) Development is within this paragraph if it is the carrying out of operations for the purpose of creating underground facilities for the storage of gas in cavities or in natural porous strata and one of the conditions in paragraph (5) is met.

(3) Development is within this paragraph if—

(a) it is starting to use underground facilities for the storage of gas other than in natural porous strata;

(b) the proposed developer is a gas transporter; and

(c) one of the conditions in paragraph (5) is met.

(4) Development is within this paragraph if—

(a) it is starting to use underground facilities for the storage of gas in cavities or in natural porous strata;

(b) the proposed developer is not a gas transporter; and

(c) one of the conditions in paragraph (5) is met.

(5) The conditions are—

(a) the working capacity of the facilities is expected to be at least 43 million standard cubic metres;

(b) the maximum flow rate of the facilities is expected to be at least 4.5 million standard cubic metres per day.

(6) Development is within this paragraph if—

(a) it is the carrying out of operations for the purpose of altering underground facilities for the storage of gas in cavities or in natural porous strata, and

(b) the expected effect of the alteration is to increase—

(i) the working capacity of the facilities by at least 43 million standard cubic metres, or

(ii) the maximum flow rate of the facilities by at least 4.5 million standard cubic metres per day.

(7) In this regulation—

“maximum flow rate” (“cyfradd llif uchaf”) means the maximum rate at which gas is able to flow out of the facilities, on the assumption that—

(a)

the facilities are filled to maximum capacity, and

(b)

the rate is measured after any processing of gas required on its recovery from storage;

“working capacity” (“cynhwysedd gweithredol”) means the capacity of the facilities for storage of gas underground, ignoring any capacity for storage of cushion gas; and

“cushion gas” (“nwy clustogi”) means gas which is kept in underground facilities for the purpose of enabling other gas stored there to be recovered from storage.