BASE INSTINCT: Amec is strengthening the foundations of the 7km long Richmond-San Rafael Bridge across San Francisco Bay, California, to increase its resistance to seismic forces. The crossing is located between the notorious San Andreas and Hayward faults, but has never yet suffered earthquake damage despite its slender proportions. Under a £40M contract Amec's US foundations unit will install 500 micropiles, of 300mm diameter and up to 70m long, in 31 piers to supplement existing raked Hpiles. New pile caps and large diameter bored piles will help reinforce a further 45 piers. All strengthening work is due to be completed by 2003.