Environmental quality risk assessment criteria for soil at manufacturing facilities
1 Scope
According to the general risk assessment method, this standard specifies the calculation method for the limit value of environmental quality criteria for soil at manufacturing facilities (hereinafter referred to as "soil criteria") and the general soil criteria limit value.
This standard is applicable to the environmental quality risk assessment of soil inside battery limits at the siting stage and after production activities at manufacturing facilities, and does not apply to mining, farmland and residential land.
2 Normative references
HJ/T 20-1998 Technical specifications on sampling and sample preparation from industry solid waste
3 Classification of criteria
Two sets of criteria are developed: soil criteriadirect contact and soil criteriamigration to groundwater.
3.1 Soil criteriadirect contact: It is used to protect workers who come into contact with soil through improper ingestion or dermal contact during production activities at manufacturing facilities. It applies to soils within the surface and 0.6 m below the surface.
3.2 Soil criteriamigration to groundwater: it is used to ensure that the drinking water sources beneath the soil inside the manufacturing facility battery limit are not contaminated by the chemical substances due to soil leaching. It is only applicable to soils above the groundwater level when the groundwater beneath a manufacturing facility is or will be used as a drinking water source.
If the groundwater beneath a manufacturing facility is or will not be used as a drinking water source, the soil criteriadirect contact shall be implemented.
4 Calculation formulae for criteria values
The criteria values for soil at manufacturing facilities are calculated using the following formulae.
4.1 Calculation formula for soil criteriadirect contact:
where,
TD0 = the target dose (mg/(kg·d)), which refers to the amount of direct oral exposure to soil per day (per unit body weight) for exposed workers under different risk conditions.
where, for those with carcinogenic risk, TD0 = 10-5/SForal;
for those without carcinogenic risk, TD0 = 1·RfDoral;
SForal = the oral slope factor (mg/(kg·d))-1*;
RfDoral = the chronic oral reference dose (mg/(kg·d))*;
BW = the body weight (kg);
AT = the average time (d);
CF = the conversion factor (106mg/kg);
EFs = the exposure frequencies (d/a);
ED = the exposure duration (a);
FC = the share of contaminated soil (unitless);
Foreword i
1 Scope
2 Normative references
3 Classification of criteria
4 Calculation formulae for criteria values
5 Generic soil criteria value
6 Soil sampling, sample preparation and test methods
7 Implementation
8 Annex A (Informative) Toxicity value of chemical substances
9 Annex B (Informative) Criteria values for groundwater
10 Annex C (Informative) Exposure factors adopted by generic soil criteria and their calculation example