Subject to sections 128, 133 and 135(3) below, a sewerage undertaker may from time to time give a direction varying the conditions which have been attached to any of its consents under this Chapter to the discharge of trade effluent into a public sewer.
Subject to subsections (3) and (4) and section 125 below, no direction shall be given under this section with respect to a consent under this Chapter—
Subsection (2) above shall not prevent a direction being given before the time specified in that subsection if it is given with the consent of the owner and occupier of the trade premises in question.
A direction given with the consent mentioned in subsection (3) above shall not affect the time at which any subsequent direction may be given.
The sewerage undertaker shall give to the owner and occupier of the trade premises to which a consent under this Chapter relates notice of any direction under this section with respect to that consent.
A notice under subsection (5) above shall—
For the purposes of this section references to the variation of conditions include references to the addition or annulment of a condition and to the attachment of a condition to a consent to which no condition was previously attached.