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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
Cadmium, total recoverable 3,237,276 25.1 25.1
Copper, total recoverable 2,436,864  Original DMR load is 2,436,859 18.9 44.06
Arsenic, total recoverable 2,314,041  Original DMR load is 2,314,021 17.9 62.02
Zinc, total recoverable 2,027,392  Original DMR load is 2,027,389 15.7 77.7
Selenium, total recoverable 938,607  Original DMR load is 938,604 7.28 85.06
Lead, total recoverable 553,173  Original DMR load is 553,168 4.29 89.3
Chlorine, total residual 211,407  Original DMR load is 211,558 1.64 90.9
Nickel, total recoverable 211,015  Original DMR load is 211,014 1.63 92.6
Aluminum, total recoverable 117,323 0.91 93.5
Chromium, hexavalent tot recoverable 99,207 0.77 94.3

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Top Receiving Watersheds (2011)
HUC-12 Code HUC Name Total DMR TWPE (lb-eq/yr)
180701060702 Alamitos Bay 9,259,071
110702040101 Wolf Creek 275,972
050200030309 West Run-Monongahela River 162,771
180701060606 Coyote Creek-San Gabriel River 144,028
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
180701040500 Manhattan Beach-Frontal Santa Monica Bay 50,442
050100090304 Chartiers Run-Allegheny River 33,710
041300010603 Keg Creek-Frontal Lake Ontario 31,865

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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)
CA0001139 AES ALAMITOS POWER PLANT LONG BEACH, CA 4911 180701060702 Cadmium 3,220,760
CA0001139 AES ALAMITOS POWER PLANT LONG BEACH, CA 4911 180701060702 Copper 2,250,198
CA0001139 AES ALAMITOS POWER PLANT LONG BEACH, CA 4911 180701060702 Zinc 2,016,626
CA0001139 AES ALAMITOS POWER PLANT LONG BEACH, CA 4911 180701060702 Arsenic 781,488
CA0001139 AES ALAMITOS POWER PLANT LONG BEACH, CA 4911 180701060702 Lead 547,596
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 CORP. BURLINGTON, KS 4911 110702040101 Arsenic 275,972

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