department of the environment ground water rule laboratory presentation
TRANSCRIPT
Department of the Environment
Ground Water Rule
Laboratory Presentation
Presentation Overview
• Why the GWR regulations were created.
• General requirements of the GWR.
• Focus on laboratory/ sampling requirements.
• Handouts/ question and answer.
Why??
• EPA is particularly concerned about ground water systems (GWSs) that are susceptible to fecal contamination because these systems may be at risk of supplying water that contains harmful microbial pathogens
Purpose of the GWR
• Reduce public health risk associated with fecal contamination for people served by groundwater sources.
– Viruses
– Bacteria
PWS Requirements Required By:
Notification of 4-log treatment of viruses December 1, 2009
Required Beginning:
Triggered source water monitoring
December 1, 2009
Corrective actions
Compliance monitoring
New sources placed in service must meet triggered source water monitoring requirements or conduct compliance monitoring for 4-log treatment of water
States can require GWSs to conduct assessment source water monitoring
To Whom Does the GWR Apply
• Systems producing and relying 100% on ground water.
• Consecutive systems receiving ground water.
• Mixed systems using surface and ground water.
– Unless they combine all their ground water with surface water prior to treatment meeting the SWTR.
Key Provisions of the GWR
1. Sanitary surveys. (MDE)
2. Corrective action. (MDE- Water Systems)1. Significant deficiencies.
2. Fecal contamination.
3. Monitoring. (You- Water Systems)1. Source Water Monitoring. (Triggered or Assessment)
2. Compliance Monitoring.
Ground Water System
Triggered SourceWater Monitoring
4 Log Treatment and Compliance MonitoringAssessment Source Water Monitoring
GWR and TCR Relationship
• TCR and the GWR work together.
• TCR positive may indicate a problem with the ground water source.
• So, a TCR positive sample triggers a “Triggered Source Water Sample”
– Exceptions
Triggered Source Water Sample
• Ground water system must.
– Collect at least 1 raw water sample per TCR positive at each source that was operating when the TCR positive sample was taken.
– Collect the triggered source water sample within 24 hours of being notified of the positive TCR sample.
• Time extension is possible.
Triggered Source Water Sample
• Must be analyzed for a fecal indicator
1. E. coli
2. Enterococci
3. Coliphage
Fecal Indicator Methodology Method Name
E. coli Colilert
Colisure
Membrane Filter Method with MI Agar
m-ColiBlue24 Test
E*Colite Test
EC-MUG
NA-MUG
9223 B
9223 B
EPA Method 1604
9221 F
9222 G
Enterococci Multiple Tube Technique
Membrane Filter Technique
Membrane Filter Technique
Enterolert
9230 B
9230 C
EPA Method 1600
Coliphage Two-step Enrichment Presence-Absence Procedure
Single Agar Layer Procedure
EPA Method 1601
EPA Method 1602
Sampling Location
• Sample at well or state-approved location
• Sample before treatment
• Might be necessary for GWS to install new sample tap
• GWSs with multiple sources may request approval from state to reduce number of locations
Systems Serving ≤ 1,000 people
• Ground water systems may use a TCR repeat sample to satisfy the GWR triggered source water sample.
– Lab must use an approved E. coli method
What if the “Initial Triggered Source Water” is Positive
• GWS must take 5 “Repeat Triggered Source Water Samples” within 24 hours of being notified of the positive “Initial Triggered Source Water Sample.”– Unless state has already required corrective action.
• See GWR Monitoring Report Form
What if any of the “Repeat Triggered Source Water Samples” are Positive
• The Ground Water System must take corrective action.
Consecutive & Wholesale Systems• Consecutive Systems
– Notify wholesale system(s) of total coliform-positive routine sample taken under the TCR
• Notification required within 24 hours
• Notification must be provided to all wholesale system(s) with ground water source(s) that had provided water to the consecutive system
• Wholesale Systems
– Upon receipt of notification from consecutive system:
• Collect samples from all ground water sources serving the consecutive system within 24 hours of notice
• For any fecal indicator-positive sample, notify all consecutive systems served by that ground water source within 24 hours
3
2
1
System B Consecutiv
e
WholesaleSystem
TC+
EC+W1 W2
System A Consecutiv
e
System A notifies wholesale GWS of TC-positive sample collected under the TCR.
Wholesale GWS samples ground water sources for fecal indicator.
Wholesale GWS notified of source water fecal indicator-positive result notifies all consecutive GWSs served by source, and undertakes state-approved corrective action(s).
Representative Monitoring
• States may allow for GWSs with multiple sources
• Allows system to collect triggered source water sample(s) that represent each monitoring site in TCR sample siting plan
• Representative sample locations must be approved by state
Triggered Source Water Monitoring Plan
• For multi-source systems:
– Identify ground water sources that are representative of each TCR monitoring site
• Each TCR site needs to be associated with at least one source
– May need to submit the plan to the state for approval (if directed by the state)
low pressure zone
Well 1Well 3
TCX
TCY
TCZ
Well 1 Well 3Well 2
Low Pressure Zone
Mixed Zone
High Pressure Zone
1800 Washington Boulevard | Baltimore, MD 21230-1718410-537-3000 | TTY Users: 1-800-735-2258
www.mde.state.md.us
Maryland Department of the Environment
Travis E. Sterner, R.S.Water Supply Program
Interior Pages
• Type.
• Here.