Kathy Metropulos Division of Drinking and Ground Waters Protecting your aquifer: What to consider when drilling oil and gas wells.
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Kathy MetropulosDivision of Drinking and Ground Waters
Protecting your aquifer: What to consider when drilling oil and gas wells.
What If?
Goal of SWAP ProgramTo protect the drinking water source
from future contamination
through planning and implementing strategies designed to protect the well field
What is SWAP?
Source Water Assessment and Protection Program
Wellhead Protection developed in 1986
Required by 1996 Amendments to the Safe Drinking Water Act
Requires that all 5,800 Public Water Systems in Ohio take Steps to Protect their Source of Drinking Water
The SWAP Process
Develop and Implement Drinking Water Source Protection Strategies
Define Protection Areas for Wells/IntakesInventory Potential Contaminant SourcesDetermine Susceptibility
The Assessment - Completed by Ohio EPA
The Protection Plan - Completed by Water System
3rd Largest pumper in NE Ohio>6 MGDPop. >50,000>19,000 Service Connections18 Large-Diameter WellsComplex Lagoon SystemNext to Cuyahoga River
Potential Contaminant Sources
Susceptibility Analysis
How susceptible is the source of drinking water (aquifer) to contamination?
High, Moderate or Low
Based On:
Type of Water System
Hydrogeologic Setting
Potential Contaminant Sources
Review of Water Quality Data
Cuyahoga Falls Aquifer Susceptibility
Ground Surface=(0 Feet)
Sand: 22 to 50 Feet
Well Information:Total Depths= 72 - 130 FeetCasing Lengths = 52 - 102 FeetWater Table = 4 - 35 Feet
Sand and Clay: 0 to 22 Feet
Sand and Gravel: 50 to 120 Feet
Creek
Public Water Well
Above-GroundStorage Tank
Ground Water Flow Direction
Potential Ground Water Flow and Contaminant Transport
Potential Chemical PlumePotential
Nitrate Plume
Septic
Oil and Gas Well
Protection Planning
Each public water system is responsible for creating a plan to protect the aquifer.
Each plan will contain regulatory and non-regulatory approaches to protecting the aquifer.
State or federal regulations do not provide for well field protection outside the 300-
foot well isolation radius.
Local authorities are responsible for protecting the well field through ordinance and other non-regulatory means.
Oil and Gas WellsThe Needs
O&G needed to reduce dependency on foreign oil
Helps US economy and supplies
Ohio has 4th largest number of oils and gas wells, behind Texas, Oklahoma, and Pennsylvania
Helps Ohio’s economy
Oil and Gas Wells the facts
In 1884, Ohio Worlds largest oil producer
To date, Ohio has produced over 1 Billion barrels crude oil, and almost 8 trillion cubic feet of natural gas
Currently, over 62,000 active wells
What’s in natural gas and oil?
Natural gas is a mixture of hydrocarbon compounds and small quantities of various non-hydrocarbons existing in the gaseous phase or in solution with crude oil in natural
underground reservoirs
Methane, ethane, propane, butane
Benzene, toluene, xylene (VOC)
Brine: Chloride, sodium, calcium, magnesium, VOCs
Drilling the Well
Drilling through aquifer formations to deep zones (4000 feet deep)
Potential for cross-contamination of aquifer and oil-bearing formation
Fluids used in the drilling process have potential to pollute ground water
Upper zones “cased” off
Drilling the Well
Oil field wastes, drilling muds, cuttings, and other fluids are a GW threat when
stored or disposed of improperly
Must be stored in pits, which are usually lined.
These wastes are usually hauled away
Want all drilling wastes hauled at end of drilling process.
Hydraulic Fracturing of Oil Formation
Hydraulic Fracturing used to increase production.
Acid fluids are put down the well before fracturing.
Fracturing is unpredictable, can create pathways to aquifer.
Fracturing fluids are often
hazardous, not regulated,
and exempt from the Safe
Drinking Water Act.
Storage
Above-ground storage tanks contain either brine or gas– Brine contains ground water, salt,
VOCs– Gas and oil contain VOCs
Above Ground Storage Tanks must be diked– Clay is usually used
Improper disposal of brine and other wastes can cause GW contamination
Brine Disposal
Brine: an unwanted by-product of drilling and production.40,000 to 50,000 barrels of brine produced daily in Ohio
Disposal:~177 brine injection wells in Ohio90-95% of Ohio’s brine disposed of in conventional
Disposal wells Also used in surface applications for dust and ice control
Other Problems
Spills
Vandalism
Acts of God
How Risky is Ground Water Contamination from Oil and
Gas Well Operations in Ohio?
Ohio EPA had ~20 cases in the last 15 years.
ODNR received 800 to 900 ground water contamination cases since the mid-1980s.
20% of these (160 – 180) are oil and gas-related.
This comes to <10 cases per year out of ~62,000 wells operating in Ohio.
Protecting the Aquifer
Drill away from protection area
Risk!
How much risk are you willing to take near the third most prolific
well field in Northeast Ohio?
Once a well field becomes contaminated,It is very expensive,
and takes a very long time, to clean up the contamination.
It would cost millions to replace Cuyahoga Falls’ well field.
Long-Term Geologic Issues
Long-term impacts to soil and ground water
The more source material, the greater the impact over time
Aquifer remediation costs
Possible need for new well field
There is no other area near Cuyahoga Falls that can produce that much water.
Protecting the Aquifer Sample raw water before drilling the oil and gas well
Ensure proper construction of new wells Double case oil and gas well through aquifer
Use non-toxic drilling and hydraulic fracturing fluids,
Use secondary containment with impervious surfaces for all storage, production, and loading areas
Inspect storage tanks and piping systems often to detect leaks and perform preventive maintenance.
Negotiate what will happen if the public well field is affected
“An Ounce of Prevention is Worth a Pound of Cure”
Protection Planning Prevents problems before
they occur
kathy.metropulos@epa.state.oh.us
SWAP Web Site:
www.epa.state.oh.us/ddagw/pdu/swap.html
Ohio EPAKathy Metropulos
330-963-1149
ODNRBob Worstall
330-284-1418 (cell)330-896-0616 (office)
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