What environmental restrictions apply to building or operating a hotel at Lake Atitlán (Decree 64-97, CONAP)?

Decree 64-97 (Aug 6, 1997) declares the Lake Atitlán basin a Multiple Use Reserve Protected Area: ≈625 km² (the lake 130 km²), administered by the national protected areas council (CONAP) under its master plan. Management zones (article 4): multiple use 139.8 km² (25%, settlements and agriculture), recovery 72.1 km², forest management 30.3 km², archaeological-cultural 76.1 km², extensive use (the lake), protective forest 147 km² and primitive 29.3 km² (the volcanic cones). Article 9 orders the prevention of 'industries or potentially polluting activities, as well as works that may cause a significant alteration of ecological conditions'. Under article 20 of the Protected Areas Act (Decree 4-89), any firm with commercial or tourism activities inside a protected area must sign a contract 'by mutual agreement with CONAP', on conditions 'determined by an environmental impact study' compatible with the master plan.