Directional Boring, often undifferentiated from Horizontal Directional Drilling (HDD), is a minimal impact trenchless method of installing underground pipe, conduit, or cables in a relatively shallow arc or radius along a prescribed underground bore path by using a surface-launched drilling rig. – wiki
Drilling fluid disposal are cost prohibitive, environmentally risky and/or threaten the mechanical integrity of the well. Chemical solidification of the pit contents and disposal into a permitted commercial injection well are expensive, particularly where large quantities of high-chloride (>5,000 ppm) mud are being injected into a commercial disposal. For a typical 14,000 ft well in Western Oklahoma, it would not be unusual to spend $60,000 for either of these methods of disposal.