Status of Nutrient Standards in Texas

Transcription

1 Status of Nutrient Standards in Texas May 28, 2010 Presented by: Ana J. Pena-Tijerina, Ph.D., P.E. David Harkins, Ph.D., P.E. In collaboration with: Raj Bhattarai, P.E., DEE Austin Water Utility

2 This Presentation Discusses the Following Items 1. Regulatory background 2. TCEQ regulatory updates 3. Nutrient limits in Texas 4. Impact on TPDES permits 5. Bacteria limits

3 Nutrients are Among the Top Causes of Water Quality Impairment Lake Texoma Algal blooms The First Falls at Lake Buchanan Rooted vegetation Source: Lake Travis

4 Nutrient Regulations are Fairly New 1. Case-by-case basis 2. A few numerical standards based on narrative criteria 3. EPA National Strategy (1998) 4. Environmental groups petition EPA to redefine secondary treatment to include nutrient removal (2007) 5. Environmental groups sue EPA to establish numerical nutrient criteria in Florida, Wisconsin, Mississippi River Basin, and Northern Gulf of Mexico ( )

5 EPA s 1998 Strategy 1. Geographic Region and Waterbody Approach 2. Waterbody-Type Guidance Documents 3. Adding Numeric Levels for Nutrients to Water Quality Standards

6 US EPA Ecoregion Delineation

7 Frequency Distribution Approach Two approaches for establishing a reference condition Value using total phosphorus as an example.

8 TP Criteria Proposed by EPA Lakes/Reservoirs Rivers/Streams TP (mg/l) Ecoregion

9 TN Criteria Proposed by EPA Lakes/Reservoirs Rivers/Streams TN (mg/l) Ecoregion

10 Nutrient Criteria from EPA We do not have ecoregional nutrient criteria recommendations for these ecoregions because there is not enough data to support them. We do not intend, at this point, to develop them, as most states are opting to develop stressorresponse based criteria rather than distribution based - Steve Potts, Office of Water, Office of Science and Technology, Health and Ecological Criteria Division, EPA Headquarters, March 24, 2009

11 Stressor-Response Based Approach 1. Establish acceptable levels of Chl a or other parameters for intended water use. 2. Find site-specific nutrient level that corresponds to the desired level of Chl a or other parameters.

12 Number of States with Adopted Numeric Nutrient Standards by Year and Water Body Type

13 EPA Nutrient Criteria for Texas Ecoregions for Reservoirs Region TP (mg/l) TN (mg/l) III IV V IX X III. Xeric West IV. Great Plains Grass and Shrublands V. South Central Cultivated Great Plains IX. Southeastern Temperature Forested Plains and Hills X. Texas-Louisiana Coastal and Mississippi Alluvial Plains

14 EPA Nutrient Criteria for Texas Ecoregions for Rivers/Streams Region TP (mg/l) TN (mg/l) III IV V IX X III. Xeric West IV. Great Plains Grass and Shrublands V. South Central Cultivated Great Plains IX. Southeastern Temperature Forested Plains and Hills X. Texas-Louisiana Coastal and Mississippi Alluvial Plains

15 Chapter 307 is under Review The TCEQ has proposed updates to the 2010 Texas Surface Water Quality Standards (TSWQS) and the Procedures to Implement the Standards (IPs) The target adoption date is June 30, If adopted, it will become effective in July, 2010.

16 Water Quality Standard The Standards are developed to maintain the quality by identifying appropriate uses for the state s surface waters. Water quality standards are the basis for establishing discharge limits in wastewater and storm water discharge permits. Sets in stream water quality goals for total maximum daily loads (TMDLs)

17 Other Nutrient Controls 1. Antidegradation provisions of the Standards (Section 307.5) 2. Watershed rules (30 TAC Chapter 311) 3. Edwards Aquifer rules (30 TAC Chapter 312) 4. Impaired Waters (303 d) Colorado River requires TP = 1 mg/l

18 How TCEQ is Planning to Determine Limits Reservoirs: Nutrient limits focus on TP rather than TN! (1) Apply general guidelines (2) If guidelines indicate potential TP limit, apply site-specific screening factors: Level of concern low, moderate, high Weight-of-evidence Streams: Similar to reservoirs with different level of concern parameters.

19 Anticipated Typical TP Limits in Texas Permitted Flow (MGD) Typical TP Limit (mg/l) < to 1.0 > More stringent limits may be recommended to protect unusually sensitive aquatic environments. Less stringent limits may be recommended when there are unusual mitigating factors.

20 Current Permits with TP Limits

21 Current Effluent P Limits Florida Everglades Lake Onondaga, NY Illinois River, OK Spokane, WA 0.05 to 0.01 Oregon; Ontario EPA Eco-Region Criteria Northern Georgia Clark County, Nevada to to 0.09 Chesapeake Bay 1.0 to Phosphorus in mg/l

22 Current Effluent N Limits Florida AWT Washington, DC Maryland ENR 3.0 LOTT, WA TIN Virginia Significant EPA Eco-Region Criteria Westchester Co, NY 0.10 to New York City UER Bucklin Point, RI Total Nitrogen in mg/l 4.0 to 9.0

23 Summary of Permit Limits and Criteria Being Considered Parameter Typical Texas Permit NRDC Proposed Secondary Treatment Draft Florida Water Quality Standards Draft EPA Criteria Guidance Phosphorus Total Nitrogen

24 How Does it Impact the Utilities? Most plants will be required to begin or increase the removal of phosphorus New treatment processes required: a. Biological nutrient removal b. Chemical precipitation c. Tertiary filtration d. Membranes This green initiative means $

25 Summary Recent regulatory updates impact the design and operation of the wastewater treatment plants. It is important to follow and review the current revisions to the TSWQS as well as the Implementation Procedures Nutrient limits are coming to Texas.

26 Changes in TPDES Permits 1. Spring 2007 EPA notified TCEQ EPA will object to any domestic waste-water permits after January 1, 2010 that do not include effluent limitations and monitoring requirements for bacteria to meet state water quality standards. 1. Jan Jan Water Quality Advisory Work Group a. addressed these concerns through a series of meetings

27 Interim Approach 1. Effective July 1, 2008 to December 31, 2009 a. Draft Permits with Notice of Application and Preliminary Decision and EPA conditional no objection letters b. Effluent Limits and Monitoring Required Domestic dischargers discharging into impaired [303(d)] water bodies for bacteria that meet 1 of following (regardless of size): Sample submitted with application exceeds 100 col/100ml New discharge or amendment to increase flow Discharges to oyster harvest waters Discharges to approved TMDL for bacteria Monitoring Frequency dependent upon result of effluent data Effluent limit at standard (or TMDL) c. Monitoring Required Large Domestic dischargers (>5 MGD) Frequency based on size of facility

28 Long Term Resolution 1. Effective January 1, 2010 State rules and procedural documents to include adopted changes to include effluent limits and monitoring of bacteria in all TCEQ domestic wastewater permits 2. These changes can be found in 30 TAC Rule 319.9(b)

29 Bacteria Monitoring Regulations 30 TAC 319.9(b) Frequency of Bacteria Measurement monitoring requirements Flow (mgd) Minimum Required Frequency Chlorine Systems Ultraviolet Systems Natural Systems >10 5/week Daily Daily >5-10 3/week Daily 5/week >1-5 1/week Daily 3/week > /month Daily 1/week /month 5/week 2/month <0.1 1/quarter 5/week 1/month **Monitoring Schedules for other constituents as described in 30 TAC 319 still apply

30 Bacteria Monitoring Regulations 30 TAC 319.9(b) A permittee that has at least twelve months of uninterrupted compliance with its bacteria limit may request a less frequent measurement schedule from the commission. Violation will require return to the standard frequency schedule. a. Facility must wait 24 months from date of violation to reapply for less frequent monitoring. A chemical system other than chlorine will be required to comply with the ultraviolet frequency schedule.

31 Effluent Limitations 1. Must meet current state standards (30 TAC 309) a. Freshwater E. coli 126 MPN/100mL (30-day average/geomean) b. Saltwater Daily max 394 MPN/100mL Enterococci 35 MPN/100mL (30-day average/geomean) Daily max 89 MPN/100mL 2. TMDL trumps standard a. Often more restrictive

32 Other Things to Consider 1. Bacteria limits and monitoring are added when: a. Renewed b. Have an amendment with renewal, or c. New domestic permit 2. DOES NOT apply to domestic TLAP permits or industrial discharge permits 3. Phased Out of sampling for Fecal coliform 4. New Proposed standard for E. coli a. 206 MPN/100mL (geomean) Pending EPA approval Expect final decision by end of 2010

33 Questions?