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Sulfate bearing soil

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I recently had a soils test done for a propsective residence. The sulfate
content came out at between .15 and .20 % by weight of soil, excpet for 1 of
9 samples which tested at 3.7%. I have asked the testing laboratory to
confirm their results, as this was also sampled within 3 feet above and
below other samples which tested at between the .15 and .20 %. The pH was
also down on this single sample to 3.5, whereas the other samples were
around 5.1 to 6.5. My question is: would it be enough to remove high sulfate
content  locally from around the foundation without resorting to Type V
cement with added pozzolans? Are there other methods to avoid sulfate or
acid attack? If the test results are correct, and I hav enot reason to
believe they are wrong, it also appears that the sulfate is not migrating.

For information, there was a significant amount of debris found in the trial
pits at 8 to 12 feet below the surface. The site was a former horse track
with a pond, which was filled in. The locations of the track and pond are
not known, but are likely to be in the vicinity of the pits. Safe bearing
capacity has been estimated at 4500 psf.

Thanks for any suggestions.

James Cohen
James Cohen Consulting, P.C.