What's New in WQS by John DeLashmit, P.E., at REGFORM's 2013 Missouri Water Seminar, Sept. 5, 2013
1. John A. DeLashmit, P.E.
USEPA Region 7
REGFORM Water Conference
September 5, 2013
2. The List
Recreational Criteria Recommendations
Ammonia Criteria Recommendations
Proposed WQS Regulation Clarifications
3. Recreational Criteria
Recommendations
Published in the Federal Register on November 29,
2012 (per Consent Decree and Settlement Agreement)
Two sets of recommended criteria; EPA will accept
either from states and tribes
Criteria expressed as a geometric mean (GM) and a
“statistical threshold value” (STV)
Freshwater may use E. coli or enterococci as indicator
Criteria are for primary contact recreation, known in
MO as Whole Body Contact Recreation
4. Recreational Criteria
Recommendations (cont.)
Averaging interval should not be greater than 30 days
Water body GM should not exceed GM criterion
during any 30-day interval
Should not be greater than 10% excursion frequency of
STV during a 30-day interval
Single-sample maximum (SSM) concentrations will no
longer be used
States are expected to address these recommendations
in their next triennial review
7. Ammonia Criteria
Recommendations
Published in the Federal Register on August 22, 2013
Supersedes recommended criteria from 1976, 1985, and 1999
Revision necessary because EPA became aware of new toxicity
studies showing the relative sensitivity of freshwater mussels to
ammonia
Since publication of draft criteria in 2009, additional studies
have validated sensitivity of unionid mussels and gill-breathing
snails to ammonia
New criteria are more stringent than 1999 recommendations
Duration components remain the same – a one-hour average for
the acute criterion and a 30-day average for the chronic criterion
States are expected to address these recommendations in their
next triennial review
10. Proposed WQS Regulation Changes
Core of current rules in place since 1983
Proposed rules were published in the Federal Register
yesterday
EPA is considering changes to the following:
Administrator’s determinations that new or revised WQS are
necessary
Designated uses
Triennial reviews
Antidegradation
Variances to water quality standards
Compliance schedule authorizing provisions
11. Proposed WQS Regulation Changes
(cont.)
The Administrator’s determination update clarifies
what constitutes an Administrator’s determination
under 303(c)(4)(B) of the Clean Water Act
The designated uses update clarifies the EPA’s
minimum expectations for designated uses
The triennial reviews update strengthens the triennial
review requirements
12. Proposed WQS Regulation Changes
(cont.)
Antidegradation update clarifies that implementation
methods are to be adopted in rule and specifies the
minimum requirements.
Variances update establishes regulatory expectations
for variances to support consistent, appropriate,
transparent and enforceable implementation
Compliance schedule authorizing provisions update
specifies that compliance schedule authorizing
provisions must be adopted as part of a state or tribe’s
water quality standards, and therefore must be
submitted to EPA for review and action