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If you're in Los Angeles County you could get a fine for burning them, since there is a moratorium on burning any wood, paper or other wood product material. They're handing out citations for lighting your fireplace even if it's a gas log fire. No barbecues.
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So far they haven't made smoking tobacco illegal.
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But ironically, come January 1st, marijuana will become legal, so I guess you won't be fined for burning that. Go figure.
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To be safe, I'd say bury the cards with some lye mixed in. If you don't have any lye then sprinkle Liquid Plumber or the like on them. Bury them deep enough so your dog won't dig them up!
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