Bacteria Rulemakin
gInclusion of Bacteria Limits
in TPDES Permits
EPA Objections EPA review 303d list for bacteria February 2007 –July 2008
Approximately 100 draft permits not approved
EPA Interim Agreement
303d list Bacteria TMDL Over 5 MGD >100 cfu/100 ml New & amended permits Oyster water Effluent limits
EPA Long Term Agreement
Propose rule by July 1, 2009
Adopt rule by Dec 31, 2009
Requires limits upon permit issuance
Objections to any permit without bacteria limits after Jan 1, 2010
Rule Timeline Proposal – May 20, 2009 Comment Period
Jun 5 – Jul 5, 2009 Adoption – Oct 28, 2009 Effective – Nov 19, 2009
Implementation Next permit action
New Renewal Amendment
EPA agreement allows no compliance schedule
Recommend starting evaluations now
Bacteria Permit Limits
Notification language in all permits E. coli for fresh water Enterococcus for salt water Limits effective at issuance
No compliance schedule Possible exceptions for small facilities
E. coli Permit Limits
Fresh Water Numerical limit in rule
OR Refer to WQ Standards WQ Standards changing
126 cfu current 206 cfu proposed
Enterococcus Permit Limits
Salt water discharges WQ Standards not changing
Numeric limit = 35 cfu
Large Domestic Facilities
Interim Sampling Schedule
>50 MGD – 5/week 20-50 MGD – 3/week 5-20 MGD – 1/week <5 –no monitoring
Monitoring Frequencies
Based on permitted flow Ultraviolet vs chlorine Increased frequency:
application screening 303d segment sensitive water body
Continued Need for Chlorine Testing
Retain 4.0 mg maximum 0.1 mg dechlor
Regular check between bacteria samples
Delay in bacteria results
Chlorine Contact Chambers
Recommend evaluating now If undersized or short-circuiting
Violating current regulations No compliance schedule
Sample Holding Times
Standard Methods 9221 & 9222 Holding time – 6 hours Travel time issues SWQM in-stream variance
Laboratory Issues In-house testing
without certification Contract lab must be
NELAC certified Proximity to plant Increased workload
21-day retention time Recommend evaluating
Capacities Sample Locations Wildlife impacts (birds, etc)
Compliance schedule for new construction
Pond Systems
Wet Weather Issues
Affects a limited number of facilities Blending Other options for stand-alone
facilities that can’t meet limits
Industrial Facilities Bacteria limits for
domestic outfalls Commingled domestic
and process outfalls Internal outfalls vs
external outfalls Monitoring frequency
Discussion Topics Questions
Suggestions
Solutions
Contact Us Kent Trede
[email protected] 512.239.1747
Sherry Smith [email protected] 512.239.0571
Chris Linendoll [email protected] 512.239.4515
Fecal vs Residual ChlorineMinor municipal facilities
(114 data points)
0
0.5
1
1.5
2
2.5
3
3.5
4
0 5 10 15 20
residual chlorine (mg/L)
Feca
l col
iform
(log
of #
/100
ml)
Fecal Coliform(log)
Single samplemaximum log(2.6)Geometricmean log (2.3)
E. coli vs Residual ChlorineMinor municipal facilities
(114 data points)
00.5
11.5
22.5
33.5
44.5
5
0 5 10 15 20
residual chlorine (mg/L)
E. c
oli (
log
of #
/100
ml)
E. coli log
Single samplemaximum log (2.6)
Geometric mean log(2.1)
Possible Limit Scenarios
EPA national criteria = WQ Stds contact criterion
A % of EPA/WQS criteria -- safety factor
Primary contact criteria from WQS at permit issuance
Individual receiving stream criterion
Current WQ Stds
Freshwater E. coli 126 cfu/100 mls Saltwater
Enterococci 35 cfu/100 mls
Proposed WQ Standards Freshwater E. coli 206 cfu/100 ml
Saltwater Enterococci 35 cfu/100 ml
Daily Maximum Limit
Current Standard E coli
394 cfu/100 ml Enterococci:
89 cfu/100 ml
Proposed Standard E coli
399 cfu/100 ml Enterococci
104 cfu/100 ml
Alternate Daily Max Method
Daily max = Daily avg x (3.11/1.47) = Daily avg x 2.12
SIP established ratio (pg 57)
Thanks for coming!
Top Related