如何创建无法访问数据的Web应用程序？

Premise: The requirements for an upcoming project include the fact that no one except for authorized users have access to certain data. This is usually fine, but this circumstance is not usual. The requirements state that there be no way for even the programmer or any other IT employee be able to access this information. (They want me to store it without being able to see it, ever.): The requirements for an upcoming proje