Complex sentence: Their condition was generally sound as of the year 2000, but the reinforcement bars of deteriorating hollow concrete block piles, which in the 1960s replaced the jarrah piles, are so corroded by saline soil that instability threatens several magazines.
Split into simpler sentences: Their condition was generally sound as of the year 2000. But the reinforcement bars of deteriorating hollow concrete block piles, which in the 1960s replaced the jarrah piles, are so corroded by saline soil that instability threatens several magazines.