Context. Noise and vibration impact studies for the Environmental Impact Study (EIA) of the Junquillos Wind Farm (owner Colbún S.A., client WSP Ambiental S.A.), located in the commune of Mulchén, Biobío Region. The project comprises 63 wind turbines, a step-up substation and a 220 kV transmission line of approximately 12 km.
Methodology. The noise baseline was characterised with 8 continuous background-noise measurement points over 14 days each, complemented by discrete measurements at the receptors within the area of influence. On that basis, noise levels were modelled at a total of 238 receptors using CadnaA software (ISO 9613), covering five environmental protection objects —human health, native fauna, ways of life and customs of human groups, tourism value and cultural heritage— for the construction, operation and closure/decommissioning phases, in daytime and night-time periods, in accordance with the 2019 SEIA Guide and Decree D.S. No. 38/2011. The operation phase incorporated the synergistic effects of nearby wind farms and the contribution of the substation and transmission line. The vibration study assessed 192 receptors associated with human health and 3 with cultural heritage, with baseline measurement at 35 receptors and level projection following the Caltrans and FTA guidelines, given the absence of a national standard.
Results. Noise modelling identified, for the construction phase, a limited set of receptors exceeding the maximum permissible levels, for which mitigation measures were proposed to achieve regulatory compliance; in the operation phase the projected levels meet the applicable standards. The vibration study concluded that the projected levels remain below the reference thresholds, ruling out vibration impact.
