30,000 words is not a small work, someone with extended focus and speed is required for this task.
I believe I have the prerequisites for this task, I have a great deal of experience in this field, I am certain that you will not be disappointed by my work.
I can and will proofread this with quality, and with speed. You can be satisfied with the belief that your work is in good hands.
If you want to contact me directly to clear any doubts about me, my work, or my language, please ask for my contact and we can have a meeting through Skype.
I hope you consider me for this position.
Thank you.