Na Nọvemba 2, Ọfịs General nke Ministry of Ecology and Environment nyere "Ọkwa banyere ibipụta na nkesa "Ndepụta zuru oke nke nchekwa gburugburu (2021 Edition)" (Environmental Office Comprehensive Letter [2021] No. 495).Na "Ndepụta zuru oke nke nchekwa gburugburu ebe obibi (2021 Edition)", unyi na-acha anụnụ anụnụ/coke/pitch (belụsọ maka distillation site na iji ikuku, ikuku ma ọ bụ ikuku na ikuku na-aga n'ihu distillation Filiks) na coking (koodu ụlọ ọrụ 2520) na ígwè ọdịnala na ígwè. ụlọ ọrụ, ígwè Rolled (ụlọ ọrụ koodu 3130) chromium-plated ígwè mpempe akwụkwọ (ma e wezụga trivalent chromium electroplating usoro) / agba-ntekwasa efere (ma e wezụga chromium-free agba mkpuchi usoro) ngwaahịa, ferroalloy smelting (ụlọ ọrụ koodu 3150) metal manganese / metal silicon / metal chromium ngwaahịa , Usoro nke ngwaahịa na-emepụta site na-ekpo ọkụ na-ekpo ọkụ galvanizing usoro na ígwè (koodu ụlọ ọrụ 3208) bụ ngwaahịa "oke mmetọ";A naghị ekepụta ngwaahịa ndị na-emepụta ígwè (koodu ụlọ ọrụ 3210) na nchara (koodu ụlọ ọrụ 3220) dị ka "oke mmetọ" na "oke ihe ize ndụ gburugburu ebe obibi" "ngwaahịa.