As the article stated, in the 1980s, hikers could park in the Omega Station lot, sign in, and start hiking. Implement a similar sign in, except that the sign in would be a sign off absolving the state and city of any and all liability, that the signer assumes 100% risk of potential major injury and/or death, that the signer relinquishes his/her right to any litigation against the state and city.  No doubt the legal minds for the state and city can come up with the appropriate language for the waiver of liability for the hikers to sign.