Barton will lead to books and some documents from the USGS and EPA. Try searching Subject Keywords combinations such as phosphorus, phosphate, environment*, anaylysis, water content. Here are some examples:
This book summarizes the most recent policies and strategies for phosphorus removal and recovery from municipal, residential and agricultural wastewater effluents and runoff..
An illustrated account of the creation of the Charles River Basin, focusing on the precarious balance between transportation planning and the stewardship of the public realm.
The highly acclaimed Encyclopedia of Analytical Chemistry provides a much needed professional level reference work for the 21st Century. Encyclopedia of Analytical Chemistry is the most comprehensive analytical chemistry reference available, covering all aspects from theory and instrumentation through applications and techniques. All fields of chemical research are covered: analytical, organic, physical, polymer, inorganic biomedical, environmental, pharmaceutical, industrial, petroleum, forensics and food science.