Hop addition question

As a rookie brewer I am interested in trying the following recipe but have a question on the addition of the hops. It states to add hops a second time at 0 minutes. My question is do you leave them in until the wort is cooled or through the ferentation process?

Blond Ale Homebrew Recipe Description:

1. Grain Bill: Crystal 40 8 oz
Crystal 10 8 oz

2. Malt extract: Pale 6 lbs

3. Hopping Schedule: Cascade 1.0 oz 0 min
Cascade (4.7%) 1.6 oz 60 min

4. Yeast: White Labs California WLP001 Ale or

W yeast American 1056 Ale

5. Fermentation Temperature: 60 to 70 degrees Fahrenheit

6. Starting Gravity: 1.045

This is a great web site that I have learned a lot from so far.

I would toss them in without a bag and let them stay in through fermentation.

Yes, you add them at 0 minutes, and then turn off the flame. The hops stay in the wort as it is cooled. Once it's cooled, you may strain the wort into the fermenter with a sanitized strainer or funnel, or just pour it in without straining. The hops will fall out to the bottom after fermentation is over. I usually don't bother to strain my wort, unless I've used a ton of leaf hops that may clog up my siphon later.