Active Well Defense in the Bakken: Case Study of a Ten-Well Frac Defense Project, McKenzie County, ND

Abstract

AbstractThe effects of well interference between existing producing wells and newly stimulated wells (commonly known as "frac hits") are of growing concern as full-density development accelerates across all the North American shale plays. Strategies to mitigate the negative effects of such interference are becoming increasingly important as frac hits become more frequent.This case study presents a second-generation active well defense project involving four new wells and six offsetting legacy wells in the Bakken and Three Forks formations located in the North Fork Field, McKenzie County, ND. The operator has experienced numerous examples of stimulation interference in this field as its development operations have progressed into the full-density phase. Stimulation interference is defined as any increase in pressure occurring in a well as a result of stimulation activities in an offset or nearby well. While such interference has not necessarily had a lasting effect on legacy production, it has in some cases resulted in the need for costly remediation due to the migration of solids into the legacy laterals. The well defense efforts described herein are intended to minimize the need for post-stimulation remediation in legacy wells by preventing solids migration.