To help diagnose generalized anxiety disorder, your health provider may: 1  Do a physical exam to look for signs that your anxiety might be linked to an underlying medical condition. 2  Order blood or urine tests or other tests, if a medical condition is suspected.
Runoff that occurs on the ground surface before reaching a channel is also called a nonpoint source. If a nonpoint source contains man-made contaminants, or natural forms of pollution (such as rotting leaves) the runoff is called nonpoint source pollution.
The less water the ground can absorb, the more runoff on the surface there will be. This is called permeability. A surface with high absorption ability has high permeability, and a surface with low absorption ability has low permeability. This image shows permeability rates for different types of surfaces (see video).