42 Engineering and surveying services; engineering services, namely, carrying out evaluations, appraisals, research work and writing reports in the fields of science and technology; scientific research; industrial research relating to civil and mechanical engineering in the fields of residential construction, construction of bridges, abutments, bridge abutments, stabilized structures on land, mechanical stabilization of land and structures, fills and embankments, retaining walls, dikes, tunnels, dams, mill ponds, river basins, tidal basins, holding basins, reservoirs and silos; chemical laboratories; testing of materials; technical project studies and research relating to civil and mechanical engineering, namely, studies in the fields of residential construction, construction of bridges, abutments, bridge abutments, stabilized structures on land, mechanical stabilization of land and structures, fills and embankments, retaining walls, dikes, tunnels, dams, mill ponds, river basins, tidal basins, holding basins, reservoirs and silos; construction consultation; technical research relating to civil and mechanical engineering in the fields of residential construction, construction of bridges, abutments, bridge abutments, stabilized structures on land, mechanical stabilization of land and structures, fills and embankments, retaining walls, dikes, tunnels, dams, mill ponds, river basins, tidal basins, holding basins, reservoirs and silos