Auckland's biggest supplier of sand for concrete is still fighting to mine a beach north of the city.

Earlier this month, McCallum Brothers was declined resource consent by Auckland Council for offshore sand extraction at Pakiri Beach, due to concerns for the likes of marine and bird life.

They have now lodged an appeal to the Environment Court, claiming the environment will be worse off, if they have to source sand from elsewhere.

Managing Director Callum McCallum told Mike Hosking there are also very few sources of consented sand which is suitable for the work they do.

He says any of the current sources either have too small a consent, in terms of volume, or they don't have the capacity.

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