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Discharge Monitoring Report (DMR) Pollutant Loading Tool

Note: This area of the DMR Loading Tool includes data used for EPA's annual review of industrial effluent discharges. EPA's Office of Water is responsible for developing programs and tools authorized under the Clean Water Act (CWA), which enables EPA and the states to protect and restore the Nation's waters. The CWA requires EPA to annually review and, if appropriate, revise its water pollution control technology-based regulations, called "effluent limitations guidelines" or "effluent guidelines" that limit the discharge of pollutants to waters of the U.S. from industrial facilities. As part of the EPA's annual reviews, EPA estimates the load of pollutants discharged using a combination of discharge monitoring report (DMR) data, from ICIS-NPDES, and Toxics Release Inventory (TRI) data. EPA also assigns a relative toxic weight to the estimated loads to rank industrial categories by toxic weighted pound equivalents (TWPE). For more background on EPA's effluent guidelines program see EPA's Effluent Guidelines website.

EPA reviews the DMR and TRI data used to calculate effluent loads and TWPE for accuracy prior to further investigating industrial categories for possible effluent guideline revisions. For identified outlier data, EPA contacts states and facilities to confirm and update (if appropriate) data values and units. For information on the methodology and types of changes identified, see EPA's most recent odd-numbered year Annual Effluent Guidelines Review Report (PDF) (169 pp, 2MB) on the Effluent Guidelines Plan webpage. Because of this review and EPA's methodology for interpreting data and calculating loads, the calculated loads and category rankings may differ from original calculations using DMR and TRI data that have not been updated. Data that have been updated by EPA's annual reviews are indicated by green flags designating that a change has been made to a concentration, quantity, or flow value. A listing of the DMR and TRI data changes from the most recent annual review is available in the Annual Effluent Guidelines Review Report Appendices (PDF) (241 pp, 3.3MB).

Point Source Category Information - Steam electric power generating (DMR)

EPA 304M Annual Review flag — Indicates load was altered by EPA’s 304M Annual Review. You can hover over the green flag to see the original load from the DMR data.

Top Pollutants - Toxic-Weighted Pounds (TWPE) (2011)
Pollutant Name Total DMR TWPE (lb-eq/yr) % of Category TWPE Cumulative % of
Category TWPE
Arsenic 1,426,285  Original DMR load is 1,426,037 43.3 43.3
Selenium 854,154  Original DMR load is 854,119 25.9 69.3
Copper 250,169  Original DMR load is 250,083 7.604 76.9
Total Residual Chlorine 175,981  Original DMR load is 176,132 5.34 82.2
Aluminum 173,403 5.27 87.5
Boron 88,846 2.7005 90.2
Mercury 45,361 1.37 91.6
Ammonia as N 42,644 1.29 92.9
Iron 32,589 0.99 93.9
Lead 24,755  Original DMR load is 24,558 0.75 94.6

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Top Receiving Watersheds (2011)
HUC-12 Code HUC Name Total DMR TWPE (lb-eq/yr)
110702040101 Wolf Creek 275,972
050200030309 West Run-Monongahela River 162,771
051402011006 Red Bush-Little Pigeon Creek 113,838
051201111601 Turtle Creek Lake-Turtle Creek 77,717
050302011009 Cow Creek-Ohio River 71,928  Original DMR load is 72,079
041401010603 Mill Creek-Frontal Lake Ontario 34,349
050100090304 Chartiers Run-Allegheny River 33,710
041300010603 Keg Creek-Frontal Lake Ontario 31,865
011000030305 Fenger Brook-Frontal Lond Island Sound 25,344
040400020101 Wind Point-Frontal Lake Michigan 24,216

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Top Facility Discharges in Toxic-Weighted Pounds (TWPE) (2011)
NPDES ID Facility Name City, State SIC Code HUC-12 Code Top Pollutant Top Pollutant TWPE (lb-eq/yr)
CA0108073 SAN ONOFRE NUCLEAR GENERATING STATION UNIT 2 SAN CLEMENTE, CA 4911 180703010403 Arsenic 525,118
CA0108181 SAN ONOFRE NUCLEAR GENERATING STATION UNIT 3 SAN CLEMENTE, CA 4911 180703010403 Arsenic 481,560
CA0108073 SAN ONOFRE NUCLEAR GENERATING STATION UNIT 2 SAN CLEMENTE, CA 4911 180703010403 Selenium 348,687
CA0108181 SAN ONOFRE NUCLEAR GENERATING STATION UNIT 3 SAN CLEMENTE, CA 4911 180703010403 Selenium 288,041
KS0079057 WOLF CREEK NUCLEAR OPERATING CO JAMES RUDEEN BURLINGTON, KS 4911 110702040101 Arsenic 275,972
WV0004731 FORT MARTIN POWER STATION MAIDSVILLE, WV 4911 050200030309 Selenium 150,098
IN0002259 VECTREN CORP - SIGECO F. B. CULLEY STATION NEWBURGH, IN 4911 051402011006 Aluminum 77,272
CA0108073 SAN ONOFRE NUCLEAR GENERATING STATION UNIT 2 SAN CLEMENTE, CA 4911 180703010403 Copper 72,693
CA0108181 SAN ONOFRE NUCLEAR GENERATING STATION UNIT 3 SAN CLEMENTE, CA 4911 180703010403 Copper 55,970
WV0000761 PLEASANTS WILLOW ISLAND POWER STATIONS WILLOW ISLAND, WV 4911 050302011009 Total Residual Chlorine 53,738  Original DMR load is 53,889

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