Construction of horizontal wells in municipal solid waste using a directional drill

Horizontal directional drilling (HDD) has been employed in many situations including cable lines under rivers and rehabilitation of pipelines under buildings and busy traffic. Within the context of a municipal landfill site, a by-product of organic waste (leachate) accumulates within an established landfill. Leachate is a liquid produced from the wastes placed inside landfills and rain that percolates through the wastes and reacts with the products of decomposition. This thesis investigates the effectiveness of employing HDD techniques to extract leachate in the municipal landfill application.; There are two primary objectives of this research: (1) Identify key parameters that influence horizontal well installations in landfill applications; and, (2) Examine the efficiency and effectiveness of employing a carrier case to protect the product pipe.; Employing HDD techniques in landfill applications provide several challenges, including unknown waste material density, unknown waste material hardness, and unknown drilling operation and waste material interaction. There are limited documented studies or research related to HDD techniques in landfill applications. In addition, conventional HDD studies cannot be directly applied in this research as the drilling medium parameters are virtually unknown.; This research incorporated a trial site to gather field data related to the primary objectives described above. The trial site is located at the Region of Waterloo Landfill site located on Erb Street in Waterloo, Ontario. The installations took place at the Original Landfill Area (OLA). The OLA is currently inactive and capped. The vertical wells, originally installed to control the leachate, have degraded resulting in the landfill gas collection system to work inefficiently. The field installation of two horizontal wells (in opposing directions) were put in practice not to replace vertical wells, but to assist in capturing and collecting leachate. The installations were monitored and key parameters were recorded.; In addition to understanding key parameters in an HDD process, the efficiency and effectiveness of using a carrier case, during the installation to protect the product pipe, was investigated. Carrier pipe material candidates included HDPE and steel. In both trials, an HDPE product pipe was within the carrier pipe to protect the product pipe from damage. A section of each carrier pipe (one HDPE and one steel) was equipped with sensors, including internal load bolt, pressure transducers, strain gauges, displacement transducers, and thermocouples, to monitor elastic and plastic deformations the carrier pipe during installation. Due to the geometry of the steel carrier pipe, only limited sensors were installed. A data acquisition system was designed and installed within the product pipe to record the sensor readings.; The results indicate that drill rig torque is essential when drilling through municipal landfill waste. Strain and displacement data from both HDPE and steel carrier pipes indicate the approximate location of hard objects within the landfill. Fluid pressure data suggest the pressure within the landfill was lower than expected.; Based on the findings within this research, coupled with similar studies in the US and UK, it is recommended that all landfill HDD installations employ maxi-HDD rig to have sufficient torque during installation. Furthermore, modification of the reamer and a cover for the swivel is recommended in future installations to prevent in-situ objects interfering with the drilling operation.