A mining operation brings together dozens of noise sources running at once — drilling, blasting, crushing, conveyor belts, processing plants and haul truck traffic — and often does so in quiet rural areas where the nearest receptors are isolated dwellings and, above all, native wildlife. That combination makes noise and vibration a recurring point of attention in the environmental assessment of mining projects, and a weak baseline tends to end in observations from the authority that delay the project schedule.
When and how mining noise is assessed in the SEIA
Mining development projects are one of the categories that enter the SEIA under the system’s Regulation (D.S. No. 40/2012), whether as a Declaration or a full Environmental Impact Study. For the acoustic component, the methodological reference is the SEA’s guide for predicting and assessing noise and vibration impacts in the SEIA: a baseline at the receptors, characterisation of the sources, modelling of the construction, operation and closure phases in daytime and night-time periods, and comparison against the stationary-source standard. Since most operations run continuously, the night-time period — the most demanding one — usually defines the outcome of the assessment.
Rural areas: the limit is set by background noise
The standard in force today is D.S. No. 38/2011, and its successor has already been published: D.S. No. 14/2024 comes into force 18 months after publication for projects entering the SEIA (27 August 2027) and 30 months after publication as a general rule. In rural areas — the typical setting for mining — the limit is not a fixed number: the new standard refers to Tables No. 6 and No. 7, whose values depend on the rural background noise level measured at the receptor itself. The quieter the surroundings, the stricter the limit, with stepped values that start at 40 dBA (for both the daytime and the night-time period). That is why the background noise measurement is not a formality: it defines the standard against which the operation will be assessed throughout its life.
Vibration and blasting: international criteria
Chile has no national vibration standard, so accepted practice in the SEIA is to assess against international criteria: those of the FTA (Federal Transit Administration) and Caltrans for annoyance to people and damage to structures, and blasting-specific criteria such as the Australian standard AS 2187-2. The assessment requires a baseline vibration condition at the receptors, characterisation of the sources — including operational blasting — and, where appropriate, control and monitoring measures.
Noise and wildlife: one of the biggest challenges for mining projects
Noise affecting wildlife is usually the worst case for the noise assessment of a mining project in the SEIA. Operations of this kind tend to be located far from dwellings, but there are often habitats of ecological relevance close to the project, which makes the wildlife noise assessment decisive. Chinchillas are a recurring case, frequently with burrows that require specific protection, so getting that assessment right is essential for the project to be sustainable.
How we help
At Acústica Austral we deliver noise and vibration impact studies for the SEIA in the mining sector: baseline campaigns with class 1 instrumentation, modelling in CadnaA, vibration assessment under FTA and Caltrans criteria, and technical responses to SEA observations through to their resolution. Among others, we produced the noise and vibration studies for the rail project connecting Minera Escondida with the ports of Antofagasta and Mejillones, which — after a first submission was not admitted for processing — was resubmitted with our studies and obtained approval.
If you are preparing a mining project for the SEIA or have already received observations, book a 20-minute call and we will review your case.
He leads Acústica Austral’s environmental noise and vibration studies for the SEIA across energy, port and infrastructure projects, and has contributed to reference work for Chile’s Ministry of the Environment.
Meet the team →Free resources for your project
Guide to the D.S. N°14/2024 and the acoustic checklist for entering the SEIA, in PDF. We email them to you.