Memorial Day Weekend 0.004 BTC ($107) Brainwallet Puzzle!

I'm giving away 0.004 BTC ($107 USD) to one clever Redditor to celebrate my 3-day weekend.

1HQrkiDXxmJddCVxswjGPC7xxmUawihzeK

The passphrase to this brainwallet is correct horse battery staple

To see the private key, you must know the salt. Here is your first clue.

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Contest expires Monday Night. Solution(s) will be posted whether prize is claimed or not. I've given out over 0.03 BTC ($800) in past contests and puzzles! If this post reaches the top, I'll post additional clues. Good luck!