She’s sitting 60-feet underground between South Jackson Street and South Main Street among a mix of native dirt and fill tossed into place from as early as the 1800s.
She has just 450 more feet to travel before leaving that fill behind. It will also mark the end of phase one in the $4 billion tunnel project that will stretch 1.7 miles from adjacent to Safeco Field to Battery Street.
The drill head is made from armoured steel and the cutter heads (tips) are tungsten carbide (hardest man made material next a laboratory diamond). They will bore right through the absolute hardest of rock. It will even cut steel effortlessly.
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KNOW YOUR MAKER BEFORE YOU'RE MADE TO
I know the ledge, his sister's a jumpoff
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