Investigation of environmental activity levels of bone-coal min-ing area in five provinces

During 1991-1993,the activity levels of the bone-coal mines were investigated in Zhejiang,Hubei,Hunan,Jiangxi and Anhui Province,respectively,where the reserve of bone-coal is about 90% of our country’s total reserve.The average of γ radiation doserate level measured for bone-coal,bone-coal cinder(BCC) and bone-coal cinder brick(BCCB) in these provinces is about 500 nGy/h,400 nGy/h and 700 nGy/h respectively,while that for fields,roads and houses made of BCCB in corresponding regions of these provinces is about 200 nGy/h,260 nGy/h and 300 nGy/h respectively.It is shown that the environmental activity level of bone-coal mining area is about 3 times higher than the reference spots.

Survey of radon concentrations in bone-coal mining areas and inside BCCB houses in five provinces

It was investigated that the radon concentrations in bone-coal mining areas,in outside and inside BCCB houses and ordinary red-brick (ORB) houses of the reference points in Hubei,Hunan,Jiangxi,Zhejiang and Anhui Provinces. It was shown that the average annual radon concentration inside BCCB houses in the bone-coal mining areas in the five provinces ranges from 85.7 to 303 Bq/m3,with an average of 151 Bq/m3,which is 3 times that inside ORB houses at the reference points. The average annual radon concentration outside BCCB houses in the bone-coal mining areas in the five provinces ranges from 12.0 to 73.8 Bq/m3,with an average of 34.9 Bq/m3,which is 1.5 times that outside ordinary ORB at the reference points. And the radon concentration in shafts of Hubei and Zhejiang Prov- ince is 9.51×103 Bq/m3 and 965 Bq/m3,respectively. This report also shows the changing patterns of radon concen- trations with day,season,height,etc.