Yes i would recommend calling and letting them know you are interested in volunterring. This way you may be able to make arrangements to go in when they can speak to you.
If you are looking for a job or volunteer work, it's always best to go in person. You can also see if they have any info on their website first
Call them and tell them you want to volunteer and they should be able to tell you how
I was told that you go up there and feel out an application and they look it over then call you sorry that is all I know
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