If you head outside the Wallach main town, to the south, going 21 east and then 7 south you will end up outside a Bene Gesserit research facility. If you go inside and follow the stairs to the top floor, to the south you'll find the Reverend Mother in charge, and she's lost an important file.
Outside her room, to the southeast there's something up with the ceiling. Push it and it should eventually lead you to a room that's locked from the outside. Search the desk for a key and then head back down the stairs. Walk around towards the north - northwest or northeast both lead you to the same spot eventually. There should be a drawer here or north where there's an admiral. Get that key with the key you found earlier, then head south of the admiral and unlock the door. In here, search statue, until you find the file. Return it for your reward: 2 quest points and 10,000 solaris.