Common Phenomena of Excessive Levels of Substances in Groundwater

Groundwater is water stored in the voids of strata below the vadose zone, including rock pores, fissures, and karst caves. Due to variations in the regions it flows through, groundwater often exhibits elevated levels of certain substances. The following are common examples of groundwater exceeding safe levels:

I. Characteristics of Groundwater with Excessive Iron Content

① Well water turns yellow: Clear well water turns light yellow after several hours to a day in a pool;

② Well water has yellow sediment: After several days, yellow iron sludge settles at the bottom of the pool, staining the pool walls yellow;

③ After boiling, the water turns slightly yellow; the higher the iron content, the deeper the yellow color;

④ Well water has an oil film: An oil film floats on the surface of the well water;

⑤ Well water has a fishy smell: Freshly drawn well water has a distinct metallic smell.

II. Characteristics of Groundwater with Excessive Manganese Content

① Manganese has a weak staining ability; its staining effect is not noticeable when iron is also excessive.

② Excessive manganese alone will stain the pool walls and the ground near water use black and cause delamination.

③ Washing clothes will darken their color.

III. Characteristics of Groundwater with Excessive Hardness

① After boiling, white lumps appear at the bottom of the kettle.

② It clogs water pipes, causing poor water flow.

③ Cleaning furniture will leave white residue.

Excessive levels of certain substances in groundwater will render it unsuitable for use. Therefore, to meet our usage standards, it should be treated before use.