[ vā′dōs′ ]
A subsurface zone of soil or rock containing fluid under pressure that is less than that of the atmosphere. Pore spaces in the vadose zone are partly filled with water and partly filled with air. The vadose zone is limited by the land surface above and by the water table below. Compare phreatic zone.
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What Does “ZIP Code” Stand For?It’s a hectic time of year for the U.S. Postal Service. Those packages you ordered on Cyber Monday are steadily arriving. You’re probably even receiving a few holiday greetings the old-fashioned way — snail mail. The half million employees who work for the USPS rely heavily on the five- or nine-digit ZIP codes for efficient and reliable mail delivery. So, it makes sense that the …
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