Objective The aim is to evaluate the environmental risk and explore the feasibility of clear water drilling cuttings soilization.

Methods The structural and chemical properties, microbial composition and pollution characteristics of clear water drilling cuttings were analyzed systematically, and the soilization experiment of clear water drilling cuttings was also carried out.

Results The main components of clear water drilling cuttings are similar to those of surface soil. The particle size distribution of cuttings is wide and the particle size distribution of cuttings from different sources varies greatly. The water retention rate is very poor and the fertility is low. Compared with the surface soil, the diversity of bacteria in the cuttings was similar; However, the diversity of fungi was significantly lower. The oil content, biological toxicity and heavy metal content of clear water drilling cuttings were all lower than relevant standards. The results of soilization experiment showed that in some treatments, the contents of Cr, Hg and Pb in plants exceeded the relevant standards, After mixing with soil in different proportions, the concentration of heavy metals in plants decreased significantly, which could meet the food safety standards.

Conclusions Clear water drilling cuttings exhibit low environmental risk, high soilization security, but low fertility, thus it is not suitable to be used as planting soil directly. The risk of heavy metal bioaccumulation can be controlled by mixing with soil in different proportions, selecting different plants or planting non-edible plants, etc., so as to realize the safe and effective soilization of clear water drilling cuttings.