Dataset DOI: 10.5061/dryad.q573n5tvp

Description

The rapid growth of unconventional oil and gas development (UOGD) in Colorado’s Denver-Julesburg (DJ) Basin has heightened concerns about noise and air quality impacts, particularly near drilling sites. This study evaluated hazardous air pollutants (HAPs) and noise exposure from UOGD operations through quantifying volatile organic compound (VOC) concentrations, monitoring noise levels, and employing air dispersion modeling. Near-pad measurements during well drilling, hydraulic fracturing, coiled tubing/millout, flowback, and early production revealed short-term spikes in UOGD-related VOCs, with benzene occasionally exceeding acute health guidelines.

The study provided the first estimates of speciated VOC emissions from coiled tubing/millout, indicated increased C8-C10 n-alkane emissions from synthetic drilling muds, and showed that closed-loop, tankless systems significantly reduce benzene and total VOC emissions during flowback. A new model (TRACER) was developed to simulate preproduction emissions. Noise levels consistently exceeded Colorado regulations at 350 feet during all activities, with C-weighted noise remaining elevated at 1,975 feet during drilling and fracking. The findings suggest that while improved operational practices and setback distances in the DJ Basin have reduced air pollution and noise exposure near UOGD, acute benzene exposure and noise remain concerns, particularly at closer distances, and may pose higher risks in other basins lacking similar regulations and practices.

Method

Air quality and noise impacts of UOGD operations conducted by three major DJ Basin operators were studied at four large well pads at three locations across the basin. Studied operations included well drilling, hydraulic fracturing, coiled tubing/millout operations, flowback, and early production. Methane and speciated volatile organic compound (VOC) measurements were made at near-pad and background locations to characterize increases in concentrations associated with specific UOGD activities. A- and C-weighted noise levels were monitored at multiple locations. Air dispersion and noise modeling were conducted to assess impacts as a function of distance from well pad operations.

Files and variables

Overview

This dataset contains results presented in the study report: Measuring and Modeling Air Pollution and Noise Exposure Near Unconventional Oil and Gas Development in Colorado and corresponding observations, simulations, and used in our analyses.

Description of the data and file structure

This dataset includes multiple zip files, each accompanied by its own README file that explains the data and file structure, data format, and instructions for executing any included scripts.

Detailed descriptions of the files are provided below:

• 1_Obs_CSU_GC.zip: Contains VOC concentrations in air samples from weekly-integrated and plume-triggered canisters deployed at near-pad locations. It also includes canisters collected during mobile sampling, on-pad sampling, and headspace analyses of drilling muds. The air samples were analyzed by a five-channel GC operated by the Jeff Collett research group at Colorado State University.
• 2_Obs_CSU_SPOD.zip: Contains 1-minute air monitoring data from SENSIT SPOD Sensors deployed near well pads. The SPOD Sensor uses a Photon Ionization Detector (PID) to provide isobutylene equivalent mixing ratios of total volatile organic compounds (TVOCs). It also provides meteorological parameters, including wind speed, wind direction, air temperature, and pressure.
• 3_Obs_CSU_Mobile.zip: Contains mobile sampling results. The mobile lab is equipped with an Entanglement AROMA VOC Sensor, a LICOR-7810 CH4/CO2 Analyzer, and an AIRMAR (RX350) weather station.
• 4_Obs_CDPHE_CAMML.zip: Contains hourly measurements of VOCs and 1-minute measurements of meteorological conditions, methane (CH4), nitric oxide (NO), nitrogen dioxide (NO2), and particulate matter (PM2.5 and PM10). This data is from the Colorado Air Monitoring Mobile Lab (CAMML) operated by the Colorado Department of Public Health & Environment (CDPHE).
  • VOCs were measured by a Markes UNITY-2 thermal desorber (TD) with a Thermo Fisher Scientific Trace 1300 GC system.
  • CH4 was measured by a Los Gatos Multi-Gas Carbon Emission Analyzer.
  • NO and NO2 were measured using a TAPI 200 Series NOx Analyzer.
  • PM2.5 and PM10 were measured by a GRIMM EDM 180 Monitor.
• 5_Obs_CU_Noise_Measurements.zip: Contains 1-second noise measurements (NoiseData_X.csv) collected by sound level meters (SLMs) at multi-well pad Sites 2 and 3.
• 6_Obs_CU_Triggered_Audio_Rcordings.zip: Contains 76 folders of triggered audio recordings from different sites on different dates.
• 7_Sim _Concentrations.zip: Contains simulated hourly and weekly concentrations using the TRACER Pre-Production Model for near-pad monitoring locations and for a range of distances for triggered events. The model is archived in a separate GitHub repository.
• 8_Sim_AERMOD_WRF.zip: Contains the WRF meteorological inputs for the AERMOD simulations as well as processed outputs from AERMOD modules.
• 9_Results_Health_Risks.zip: Contains hazard quotients and indices calculated based on weekly, triggered, and CAMML VOC measurements.

Data Formats

• .csv: Contains quality-controlled observation results from air monitoring sites.
• .xlsx: Utilized for organizing and presenting data.
• .txt: README files.
• .wav, .ogg: Triggered audio recordings.

Code/software

Software

• TRACER Pre-Production model is available at: https://github.com/dp7-PU/HEI_TRACER_Preproduction.

Access information

Data used to derive emission rates is archived separately at: https://doi.org/10.5061/dryad.g1jwstqzs.