Start with dates, times, location, weather, the type of sound, and a short description of what changed. Keep recordings and notes organized, but do not claim a source without evidence.
Then compare the observations to permit conditions, testing schedules, and the local complaint process.
What to verify locally: A structured log makes a concern easier for a regulator or operator to evaluate.
Build a usable record
Use original public records whenever possible. A developer statement can explain an intent; an approval, permit, or utility filing is where enforceable details are more likely to appear.
Know where to complain
Record the date, document title, agency, page number, and project address. That turns a claim into something another reader can check.
Evidence standard: this guide avoids treating a proposal as a completed project, and avoids treating a missing record as proof that no impact exists.