OFFICE OF GROUNDWATER TECHNICAL MEMORANDUM 2009.03
Subject: GROUNDWATER: Ground water versus groundwater
It has been a longstanding practice within the USGS to spell ground water as two words and to hyphenate when ground water is used as a modifier (e.g., ground-water hydrology). Ground Water Branch Technical Memorandum 75.03 ([water.usgs.gov]) issued just [...]
