Can someone out there verify my conversions? I get higher values and don't want to mislead anyone.
ppb = 1/billion.
78,000 ppb = (78,000 oz)/(1,000,000,000 oz) x (32000 oz)/(1 ton).
Or
78,000 ppb = (78,000 g)/(1,000,000,000 g) x (907184.7 g)/(1 ton).
These work out to 2.5 oz/ton or 71 g/ton.