Mepa said today it has acted within the parameters of existing laws and policies in the case of development at Wied il-Ghasel.
NGOs and Mosta residents yesterday staged a peaceful rally against the development of apartments and garages in the valley.
They insisted that although in 2002 the planning authority had proposed that the line of development should retreat to protect the valley, seven years later it issued a permit for the development of 26 apartments and garages.
But the authority said this evening that a number of issues were wrongly interpreted.
It said that in 2004, it granted an outline development permit to demolish an existing dwelling and to construct an old people's home, which included a considerable area outside development zone.
At that time, Mepa insisted that the development would only be permitted within the development boundaries.
Eventually an outline permit was issued for development on the same site, within development schemes.
It said that although the outline development permit was issued for an old people's home and the full development permit was granted for the construction of apartments, both uses were acceptable within development boundaries.
Mepa said that the NGOs were wrong to assume that its decision put a girna on site under threat.
"The conditions of Mepa development permit stipulate a bank guarantee of €50,000 and require the developer to restore the girna.
"In this regard, one has to mention that the way the proposal was restrained within development zone will also manage to screen a considerable stretch of less attractive back elevations."
The authority's decision is subject to an appeal currently pending before the Environment and Planning Review Tribunal, which is completely independent from the Authority.
"It is pertinent to note, that whereas under the provisions of the Development Planning Act, most of which has been repealed, a third party appeal does not suspend the execution of a development permit.
"Under the provisions of the new Environment and Development Planning Act, in case of an appeal involving a site which lies outside the development zone or in a protected area, in a case of a scheduled property (level 1 or 2), in a property where there is archeology or in cases of demolition of facades in UCA, the execution of a development permit is suspended pending such an appeal.
"Therefore, this particular case does not fall under this regulation since the site mentioned in this article falls within the development boundaries," Mepa said.
It pointed out that this particular case was determined much prior to the coming into force of the new legislative and administrative procedures, which were intended to enhance and ensure that all decisions were transparent and subject to sustainable development principles.
It welcomed active participation by residents and NGOs, and said it listened to their concerns.
"However, Mepa is an institution that is mandated to act within the parameters of existing laws and policies, and in this case it has acted entirely within these parameters," it said.