Evolution of multi-well pad development and influence of well pads on environmental violations and wastewater volumes in the Marcellus shale (USA).

A majority of well pads for unconventional gas wells that are drilled into the Marcellus shale (northeastern USA) consist of multiple wells (in some cases as many as 12 wells per pad), yet the influence of the evolution of well pad development on the extent of environmental violations and wastewater production is unknown. Although the development of multi-well pads (MWP) at the expense of single well pads (SWP) has been mostly driven by economic factors, the concentrated nature of drilling activities from hydraulic fracturing and horizontal drilling operations on MWP suggests that MWP may create less surface disturbance, produce more volumes of wastewater, and generate more environmental violations than SWP. To explore these hypotheses, we use geospatial techniques and statistical analyses (i.e., regression and Mann-Whitney tests) to assess development of unconventional shale gas wells, and quantify environmental violations and wastewater volumes on SWP and MWP in Pennsylvania. The analyses include assessments of the influence of different types of well pads on potential, minor and major environmental events. Results reveal that (a) in recent years, a majority of pads on which new wells for unconventional gas were drilled are MWP, (b) on average, MWP have about five wells located on each pad and thus, had the transition to MWP not occurred, between two and four times as much land surface disturbance would have occurred per year if drilling was relegated to SWP, (c) there were more environmental violations on MWP than SWP, but when the number of wells were taken into account, fewer environmental violations per well were observed on MWP than on SWP, (d) there were more wastewater and recycled wastewater volumes per pad and per well produced on MWP than on SWP, and (e) the proportion of wastewater that was recycled was higher on MWP than SWP. This study sheds light on how the evolution from SWP to MWP has influenced environmental violations and wastewater production in a field that has undergone rapid development in recent years.

Bone Health Screening Practices Among Neurologists in Patients on Antiepileptic Drugs: A Quality Improvement Project.

BACKGROUND: Pediatric patients with epilepsy are at risk for low vitamin D levels, increasing the risk for bone fractures, yet standardized bone health screening is not part of routine care. METHODS: We surveyed pediatric neurologists (n = 68) at our center regarding screening practices, using an 11-item survey; constructed a bone health treatment algorithm; and developed a training intervention to improve screening rates. RESULTS: The overall survey response rate was 47%. Among respondents, 64% estimated that they screened for bone health less than 25% of the time. Chart review before the intervention demonstrated an overall screening rate of 25.1% (n = 50/199). One year after implementation of a standardized algorithm, the overall screening rates increased to 53.8% (n = 100/186). The frequency of prescribing vitamin D for patients treated with antiepileptic medications increased among general neurologists (preintervention rate 16%, postintervention rate 51%, P < 0.01) as well as among epileptologists (preintervention rate 45%, postintervention rate 57%, P = 0.04). CONCLUSION: In a relatively short follow-up period, there were significant changes in care patterns regarding screening for bone health in pediatric patients with epilepsy. Further implementation measures are underway to increase bone health screening and care in this population.