Offer Text Edit
Commander Vale believes that the Alchemist might attack the Wellspring Temple, in an attempt to reach the Guardian of Water ... for what nefarious purpose I am afraid to speculate. There has been no word from either Vale, or the Guardian. Scout the Wellspring Temple, and determine if the Guardian of Water is in any danger.
Followup Text Edit
I must be on my way soon. If the Alchemist is attacking Guardians, he will be after the Guardian, at the Watchweald Temple ... assuming the Vanquisher failed to stop him at the Wellspring. The Guardians are immensely powerful beings. They control the elements, and thus provide for life. But they are not inviolate; a sufficiently powerful attacker could overcome them. If the Alchemist was able to do so, then the threat he poses is greater than anything the world has faced since the Netherim invasion a millennium ago.
The story so far...
It appears you were too late! The Alchemist has already reached the Enclave ... and was rebuffed by the Estherian Grand Regent, Eldrayn. The Alchemist fled toward the south, through the Path of the Honored Dead, toward the Wellspring Temple.
Shortly afterward, Commander Vale, another of the Heroes of Torchlight, and a close friend of the Destroyer's, arrived with a platoon of troops. She quickly set off for the Wellspring Temple, to protect the Guardian of Water, in case the Alchemist struck there next. There has been no word from her since.
First, go through the Path of the Honored Dead to access the Temple Steppes. Once in the Temple Steppes, travel to the Wellspring Temple and defeat General Grell on the third floor. Once General Grell is defeated, talk to Commander Vale to complete the quest. After speaking to Commander Vale, interact with the Guardian of Water to begin the next quest, The Guardian's Tale.
Completed Text Edit
I don't know who you are ... but I'm glad you came along! We arrived just as the Alchemist was subduing the Guardian, but he caught us by surprise. We couldn't stop him. Grell and his raiders arrived shortly after the Alchemist left. They've been trying to get in here and loot this place for years; the Alchemist's attack finally gave them the opening they needed.