How to create unique GPG Keys for different environments / projects
If you want to create separate key pairs that are not dependent on your personal keys, the easiest way is to use a separate GPG home directory for each. For example, to create keys for "projectB", first create an empty directory, then tell gpg to use that dir as its home:

mkdir projectB-gpg
gpg --homedir ./projectB-gpg --gen-key


That will do what you want, although you will now have the problem of distributing the private keys and passwords securely to each environment.