The nation’s environmental tribunal froze activity on 64 lots because it said the development endangers the Zona Protectora Cerros de La Carpintera.
The Municipalidad de la Unión was ordered to withhold permits for construction until the issues are resolved.
The lots belong to 47 owners, and they range from 103 to 1,000 square meters, well below the 5,000-square meter minimum for properties near protected areas, officials said.
The agency, the Tribunal Ambiental Administrativo, noted homes being built in risky areas, excessive terracing of the land for homes and a number of other environmental faults. The properties are in the Distrito San Diego.
The development, itself, is on just seven hectares, a bit more than 17 acres.
The tribunal said it would investigate the legality of the entire subdivision. It also is seeking hydrology studies because the suspicion is that there are springs and water recharging areas there.