Transcript Protecting Your Drinking Water

Protecting your aquifer:
What to consider when
drilling oil and gas wells.
Division of Drinking and Ground Waters
Kathy Metropulos
What If?
Goal of SWAP Program
To 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
The Assessment - Completed by Ohio EPA
Define Protection Areas for Wells/Intakes
Inventory Potential Contaminant Sources
Determine Susceptibility
The Protection Plan - Completed by Water System
Develop and Implement Drinking Water Source
Protection Strategies
3rd Largest pumper in NE Ohio
>6 MGD
Pop. >50,000
>19,000 Service Connections
18 Large-Diameter Wells
Complex Lagoon System
Next 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 and Clay: 0 to 22 Feet
Sand: 22 to 50 Feet
Sand and Gravel: 50 to 120 Feet
Well Information:
Total Depths= 72 - 130 Feet
Casing Lengths = 52 - 102 Feet
Water Table = 4 - 35 Feet
Potential Ground Water Flow
and Contaminant Transport
Above-Ground
Storage Tank
Oil and Gas
Well
Septic
Public
Water Well
Creek
Potential
Nitrate Plume
Potential Chemical
Plume
Ground Water Flow Direction
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.
Local authorities are
responsible for protecting
the well field through
ordinance and other nonregulatory means.
State or federal regulations do not provide
for well field protection outside the 300foot well isolation radius.
Oil and Gas Wells
The 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 Ohio
90-95% 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 gasrelated.
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
Protection Planning
Prevents problems before
they occur
“An Ounce of Prevention is
Worth a Pound of Cure”
ODNR
Ohio EPA
Bob Worstall
Kathy Metropulos
330-284-1418 (cell)
330-963-1149
330-896-0616 (office)
[email protected]
SWAP Web Site:
www.epa.state.oh.us/ddagw/pdu/swap.html