Sand Mining and Transport: Potential Health Effects. Thomas M. Peters, PhD, CIH Associate Professor University of Iowa Iowa City, IA

Transcription

1 Sand Mining and Transport: Potential Health Effects Thomas M. Peters, PhD, CIH Associate Professor University of Iowa Iowa City, IA Midwest Environmental Health Policy Summit Feb 2014

2 Hydraulic Fracturing Well 2

3 Sand In The Heartland 500-million-year-old rock formations contain high quality silica sand Deposits particularly wellsuited for hydraulic fracturing (fracking) Round and hard Can be screened to be a certain size Ideal for use as a proppant to hold open fissures in stone in a frack well 3

4 Example In Illinois Peru/Lasalle Ottawa Starved Rock State Park

5 Sand Mining Remove overburden Extract deposit Transport to processing

6 Sand Processing & Shipping Barge Truck Train

7 Many Complex Issues Community issues involved in deciding whether to develop this resource Pros Develop economic base Increase jobs Cons Increase pollution Increase noise, trucking Road wear Loss of natural beauty Loss of tourism doi: 7

8 Mass Particulate Matter (PM) Air Pollution Hot processes Vapor particle Dp < 1 µm Combustion (e.g., diesel engine) Mechanical processes Dp > 1 µm Grinding, sanding, excavating Fume Smoke Smog Vapor Nucleate Condense Dust Mist Spray Mechanical Generation µm nm Particle Diameter 8

9 Basis for PM Regulation Increased respiratory symptoms, such as irritation of the airways, coughing, or difficulty breathing Decreased lung function Aggravated asthma Development of chronic bronchitis Premature death in people with heart or lung disease 9

10 PM Regulations EPA (community health) All particle types PM smaller than 10 um (PM 10 ) <155 ug/m 3 over 24-hr PM smaller than 2.5 um (PM 2.5 ) <12 ug/m 3 annual avg; <35 ug/m 3 over 24-hr Only measured in 8 locations in Iowa State issues permits to ensure compliance MSHA and OSHA (worker health) Respirable (~PM 4 ) Particles that enter the deep lung All particle types and specific compounds 10

11 Respirable Crystalline Silica Specific component of PM of concern for mining of sand Silicosis (fibrosis or scarring of lung) Lung cancer Regulatory levels OSHA PM µg/m 3 Protect workers Some states (MN, CA) PM 4-3 µg/m 3 Protect everyone, including venerable populations 11

12 Silicosis Repeat injury; granuloma formation; scarring Normal Alveolus Injured Alveolus Gradual progression Once scarring, generally irreversible

13 Are there risks? We know PM and respirable crystalline silica are hazards. But what about from sand activities? What do we know about exposures? 13

14 Exposures From Sand Mining, Processing, and Handling Sand mining and processing generate airborne PM and respirable crystalline silica Blast, load, and haul Process activities such as crushing Shipping and disposal of waste sand Occupational exposures (miners, transporters) Common to exceed OSHA standards for respirable cyrstalline silica Ways to control are well documented Community exposures Less clear No required monitoring 14

15 Our Work: Answer Several Questions 1. Is particulate matter from sand mining operations hazardous? 2. What are community exposures to PM and respirable crystalline silica? 3. What are risks of developing adverse health effects from inhalation of particulate matter from a sand mine? 15

16 Is PM from sand mining operations hazardous? Collected sand types Unprocessed sand from mine Processed frac sand Characterize physicochemical properties Size distribution Composition Evaluating toxicity Cell testing (in vitro) Done On-going Summer 16

17 Sieve Analysis Mine Sand 60 Mesh Sizes 40 Sand is not one size fines Processed Sand fines Particle Diameter, µm Largest sand removed Some fines removed but a lot still present Fines present health hazard

18 Mass Concentration Wind Simulation Respirable (< 4 µm) Median Diameter = 2 μm Particle Diameter, µm Wind blowing over mine sand or processed sand can generate airborne respirable particles Next, we will assess crystalline silica content

19 What are community exposures to PM and respirable crystalline silica? Atmospheric dispersion modeling Air monitoring and sampling 19

20 Sites to Model Processing Plant with Sand Piles Sand Mine

21 Model Inputs And Receptors Processing Plant Property Line Model Inputs Dust emission rates for sources Topography Meteorological data Receptors Preschool Hospital Wind Rose

22 Sand Processing Emission Sources Wash & Screen Sand from mine Dry to remove moisture Load on trains Silo Storage

23 PM10 Without Fugitive Emissions Preschool Highest values Hospital 23

24 Open Mine Modeling WDNR Lists the following as sources of PM Drilling Blasting Crushing Screening Conveyers/Stackers Material Handling Paved Hauling

25 Air Sampling And Monitoring Traditional air sampling EPA reference method sampling in towns with heavy mining Respirable crystalline silica monitoring outside homes Real-time monitoring First deployment trains carrying sand Other processes (load barges, processing plants, etc) Low-cost detectors <~$1k for continuous monitoring of mine or process Starting Up Starting Up Summer

26 Real-time Monitoring Camera Sound and Vibration Triggers Particle Monitor trains per day pass on two tracks

27 12:54 13:19 13:43 14:08 14:33 14:59 15:25 15:50 16:16 16:41 17:06 17:30 17:55 18:19 18:43 19:07 19:32 19:56 20:21 20:45 21:09 21:33 21:57 22:22 22:46 23:10 23:34 23:58 0:23 0:47 1:11 1:35 1:59 2:23 2:47 3:11 3:35 4:00 4:24 4:48 5:12 5:36 6:00 6:24 6:48 7:12 7:36 8:00 8:24 8:48 9:12 9:36 10:01 10:25 10:49 11:13 12:54 13:19 13:44 14:10 14:36 15:03 15:29 15:55 16:21 16:47 17:12 17:38 18:03 18:27 18:52 19:17 19:43 20:08 20:33 20:58 21:23 21:47 22:12 22:37 23:02 23:27 23:52 0:17 0:41 1:06 1:31 1:55 2:20 2:45 3:10 3:35 4:00 4:24 4:49 5:14 5:39 6:03 6:28 6:53 7:17 7:42 8:07 8:32 8:56 9:21 9:46 10:11 10:35 11:00 11:25 Trains Cause Spike In PM 10 PM10, µg/m Almost all spikes in concentration correlate with train passing Sometimes spike missing or much lower Train 1 Time trains 0 No Train Time Night Next: Associate types of trains from pictures with spikes Clear problem with train detection; suspect wind

28 Low-Cost Detectors Summer Best practices to suppress dust from sand mining operations are available However, no monitoring is performed to ensure practices are followed EPA monitors are too expensive ($20K each) We will apply low-cost detectors ($400) to assess PM concentrations near sand mines

29 Summary Sand is big business in the Heartland of the US Sand mining operations present complicated issues that state agencies and local communities must deal with We hope to answer some key questions related to ambient air exposures PM 4 / respirable crystalline silica PM 2.5 / PM 10 29