Presigned URLs with ExAws

Hello! I am using ExAws and the code below to make a presigned request for uploading image files to Amazon S3. All is well except that the permissions on the uploaded file are not being set to public-read:

 def make_presigned_url(bucket, path, mime_type) do
    query_params = [{"ContentType", mime_type}, {"ACL", "public-read"}]
    presign_options = [query_params: query_params]
    {:ok, presigned_url} = ExAws.Config.new(:s3) 
        |> ExAws.S3.presigned_url(:put, bucket, path, presign_options)
    presigned_url 
 end

Do you see any other mistakes?

PS. Here is .typical presigned url produced with the above:

https://s3.amazonaws.com/noteimages/jxxcarlson/carr_fire_2.jpg?ACL=public-read&ContentType=image%2Fjpeg&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=AKIAJQYJYCIAWH6DGHIQ%2F20180809%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Date=20180809T045031Z&X-Amz-Expires=3600&X-Amz-SignedHeaders=host&X-Amz-Signature=e6e620f563606cfea26340c0f8f402bad35a5c50a841b25d5168bccf52f6da15