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Implementation Procedures (IPs)
Brittany LeeStandards Implementation
Team512-239-5210
Functions of theStandards Implementation Team
• Technical Review of TPDES Applications• Implementation Procedures for the Texas
Surface Water Quality Standards (RG-194)• Receiving Water Assessments• 401 Water Quality Certification and
Mitigation Banks
Technical Review Process
Administrative Review
**Water Quality Standards Review**
Critical Conditions Review
Dissolved Oxygen Modeling Review
**Biomonitoring Review**
Permit Writer
TPDES Standards Review
• Assess receiving water flow status
• Assign aquatic life uses and associated criteria
• Perform nutrient and TDS screening
• Antidegradation reviews
• Endangered Species review
What are “Implementation Procedures (IPs)”
• A guidance document that explains how TCEQ applies the Texas Surface Water Quality Standards to wastewater permitting
• Example: The Standards assign a 5.0mg/L DO criterion to a segment of the Colorado River
• The IPs establish DO modeling methods to ensure the limits in a wastewater permit will maintain a 5.0 mg/L DO criterion in the river
What’s New with the IPs
• Triennial review process
• EPA approved most of the 2010 IPs on July 12, 2013
• Next water quality standards revision: 2017
• Next IPs revision also targeting 2017
EPA Objections to 2010 IPs:
• Dechlorination • Variances
• Whole Effluent
Toxicity
Dechlorination
IPs propose dechlorinationrequirements for new and expandingdomestic discharges with designflows between 0.5 and 1.0 MGD
Biomonitoring Review
• Focused on “WET”-Whole Effluent Toxicity• Exposure of an invertebrate and
vertebrate species to predict impacts to aquatic life (lethal and sublethal)
• Uses the most recent 5 years of testing, determines reasonable potential
• Formulates language, and “Toxicity limits”
Approved 2010 IPs – Highlights
Changes to Minimum Analytical Levels (MALs) -
now in effect
Nutrient Screening
▸Phytoplankton in open water▸Attached algae; floating algae▸Rooted vegetation▸Aesthetic effects on recreation▸Water supplies: THM, taste & odor▸Aquatic-life: fisheries ↑↓ habitat ↑↓
DO at night↓ diversity↓
IPs – Nutrient Narrative Criteria
30 TAC Chapter 307.4(e):
“Nutrients … shall not cause excessive growth of aquatic vegetation which impair an existing, attainable, or
designated use.”
Nutrients – Typical TP Limits
Permitted Flow (MGD) TP Limit (mg/L)
< 0.5 1.0
0.5 – 3.0 1.0 – 0.5
> 3.0 0.5
Nutrients – Nitrogen Limitations
TN limitations to prevent potential impact to sea grass communities.
Consideration of site specific conditions influencing dispersion and discharge volume in relation to the proximity of sea grasses to outfall.
In the absence of numeric criteria, nitrogen limit recommendations are based on Best Professional Judgment (BPJ) and available site specific data.
Reservoir Criteria• Criteria were
proposed for 75 reservoirs
• EPA approved about half of the criteria proposed
• How does that affect me??
Challenges Ahead
316(b)
Temperature
pH Objections
IP revisions
316(b)-Intake Structures
• EPA’s final rule for existing facilities became effective October 14, 2014
• TCEQ working with EPA and permittees on application/information requirements and implementation issues
• Court challenges still pending
Temperature
Temperature screening stakeholder group started in August 2014
TCEQ is taking initial comments and working on detailed procedures for inclusion in the IPs
Draft procedures to be presented to stakeholders in summer 2016
pH Objections Screening procedure
established with EPA concurrence for certain direct discharges to classified segments
pH Sceening conducted: for major municipal
facilities (≥1 MGD flow)
for industrial process water discharges
Any
Questions
???
