Years later, I was pals with one Don H, who had a co-share in our hot-air ballooning syndicate. Don had recently retired from the RAF as an air-commodore, and had been a squadron leader at the time of the Torrey Canyon. The initial attempts to set fire to the oil had failed, he said, and he had been part of a dive-bombing team which had attempted to encourage combustion by bombing the wreck with sodium (potassium?) chlorate - containig incendiary devices.
Attempts to burn off the crude oil failed - and it ended with thousands of gallons of detergent dispersants being sprayed into the ocean - with devastating effects on marine life that lasted for years.
Chlorates are powerful oxidsing agents, an ingredient of the notorious "weedkiller' bombs. This retired scientist had much entertainment from sodium chlorate as a teenager when it was still available - pre-IRA - as a weedkiller, as did the lads on a neighbouring estate, who used to make "pipe-bombs" from it (sugar/weedkiller mixture).