Dubbed “bio-blocks,” they offer a zero-carbon substitute to their concrete alternatives and were engineered by Prometheus Materials and the Chicago-based architecture firm Skidmore, Owings ...

The tiniest blocks are less than an inch long, smaller than a domino or a miniature toy car. The largest are 22 inches long, surpassing the size of a standard concrete block from a hardware store.

But there are also concrete blocks in parking strips in Ballard, SoDo and North Seattle. The blocks are cheap, costing $20 to $40 each.

Six more concrete blocks, some of which contained chemical drums, have been found buried at Bethpage Community Park, according to the state Department of Environmental Conservation. The DEC says ...