Well spacing is one of the biggest decisions in a field development in unconventional shale plays. Not having optimized well spacing will either cost the operators additional capital or increase potential for unearned revenue. Well spacing must be close enough to contact as much stimulated reservoir volume (SRV) as possible, while taking advantage of time value of money. However, it must be far enough to minimize fracture interference (well to well interference and frac hits) and over-capitalization in a field development. Well spacing is impacted by many factors. The most important parameters requiring more study are matrix permeability, fracture half-length, dimensionless fracture conductivity (impacted by completions design), reservoir properties, capital expenditure, operating costs, and gas pricing.
Deep dry Utica/Point Pleasant Shale is a new resource with limited data. The optimum well spacing in deep dry Utica is yet to be determined. This paper goes through a practical workflow that can be used to estimate the optimum well spacing based on various forecasts obtained from various half-length, permeability, and dimensionless fracture conductivity assumptions using hybrid or numerical models. In addition, a sensitivity analysis will be performed on the impact of gas pricing, capital expenditure, OPEX, permeability, and conductivity on the optimum spacing design selection. To create long term value for the shareholders, well spacing must be selected based on NPV. Production volumes could be important to the strategic development of a company, but the single economic parameter that creates long term value for the shareholders of a company is NPV. Therefore, NPV is used to optimize well spacing in this analysis. A case study from a successful deep dry Utica well located in Westmoreland County, PA will also be reviewed and presented as part of the workflow in this paper.