my country's current "Groundwater Quality Standard" was issued in 1993. Over the past 14 years, my country's groundwater pollution has undergone new changes, and water quality monitoring technology has also made great progress. Recently, the new version of the "Groundwater Quality Standard" jointly proposed by the Ministry of Land and Resources and the Ministry of Water Resources was officially released. This standard has made many revisions to the original content. The main technical changes are as follows:

The water quality indicators have been increased from 39 items in GB/T14848-1993 to 93 items, an increase of 54 items;

Divide groundwater quality indicators into conventional indicators and unconventional indicators;

The number of sensory properties and general chemical indicators increased from 17 to 20, with the addition of three indicators: aluminum, sulfide and sodium; the permanganate index was replaced by oxygen consumption, and the four indicators of total hardness, iron, manganese and ammonia nitrogen were revised;

The number of inorganic compound indicators in toxicology has increased from 16 to 20, with the addition of four indicators, namely boron, antimony, silver and thallium, and the revision of 11 indicators, namely nitrite, iodide, mercury, arsenic, cadmium, lead, beryllium, barium, nickel, cobalt and molybdenum;

The number of organic compound indicators in toxicology indicators increased from 2 to 49, including chloroform, carbon tetrachloride, 1,1,1-trichloroethane, trichloroethylene, tetrachloroethylene, dichloromethane, 1,2-dichloroethane, 1,1,2-trichloroethane, 1,2-dichloropropane, bromoform, vinyl chloride, 1,1-dichloroethane, 1,2-dichloroethylene, chlorobenzene, o-dichlorobenzene, p-dichlorobenzene, trichlorobenzene (total amount), benzene, toluene, ethylbenzene, xylene, styrene, 2,4-dinitrotoluene, 2, 6-Dinitrotoluene, naphthalene, anthracene, fluoranthene, benzo(b)fluoranthene, benzo(a)pyrene, polychlorinated biphenyls (total amount), hexachlorocyclohexane (lindane), hexachlorobenzene, heptachlor, atrazine, pentachlorophenol, 2,4,6-trichlorophenol, di(2-ethylhexyl) phthalate, carbofuran, aldicarb, dichlorvos, methyl parathion, malathion, dimethoate, chlorothalonil, 2,4-DT, chlorpyrifos and glyphosate; DDT and hexachlorocyclohexane were replaced by DDT (total amount) and hexachlorocyclohexane (total amount), respectively, and the amendments were made;

The total alpha radioactivity was revised in the radioactivity index;

The relevant regulations on comprehensive evaluation of groundwater quality have been revised.