37 Oil and gas well drilling, and oil and gas well completion and workover services, namely, preparing wells for production and cleaning, repairing and maintaining re-entered wells; plugging and abandonment of oil and gas wells; laying and construction of pipelines; oil field construction and maintenance services of drilling location and well site pads; installation and maintenance of surface production equipment, flow lines and gathering lines; rental of water filtration units for industrial use; rental of oil and gas well drilling tools, production testing units, and fishing tools; environmental remediation services, namely, oil field waste disposal; snow removal services; mixing, pouring and laying concrete used to plug oil and gas wells and build oil field structures; rental of industrial X-ray equipment; contract oil and gas well drilling services