At my parents place the previous owners used to bury their garbage here. My parents have lived here for over 26 years and it hasn;t caused too many problems, but occasionally in the paddock weird things surface up hehe. Also when it rains some little sink holes occur, eeep! Nothing too dangerous so far, fingers crossed, most of the known places we have dug up and removed the most of it and repacked the earth to avoid the sink hole things.
We still know of some older families in the area who refuse to use the garbage collection and bury their garbage. If council found out they could get into a lot of trouble as it is not allowed anymore because garbage collection is included in your yearly property rates. It is kinda gross when it rains alot cause you can relly smell which places are burying it!