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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 more information on the types of errors identified, see EPA's Technical Support Document for the 2010 Effluent Guidelines Program (PDF) (255 pp, 3.4MB). Because of this review, and EPA's methodology for interpreting data and calculating loads (explained in EPA's Technical Support Document for the Annual Review of Existing Effluent Guidelines and Identification of Potential New Point Source Categories), the calculated loads and category rankings may differ using DMR and TRI data that has not been updated. Data that have been updated by EPA's annual reviews are flagged by green flags designating that a change has been made to a concentration, quantity, or flow value. View a listing of the changes for the most recent annual review (PDF) (1 p, 7K).

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 3,246,697 20.4 20.4
Arsenic, total recoverable 2,478,703 15.6 36.1
Copper, total recoverable 2,459,530 15.5 51.6
Zinc, total recoverable 2,032,124 12.8 64.4
Cadmium, total (as Cd) 1,460,130 9.21 73.6
Selenium, total recoverable 949,236 5.98 79.6
Hydrazine 929,297 5.86 85.5
Lead, total recoverable 570,886 3.601 89.1
Chlorine, total residual 229,489  Original DMR load is 229,643 1.44 90.5
Nickel, total recoverable 211,312 1.33 91.8

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Top Receiving Watersheds (2011)
HUC-12 Code HUC Name Total DMR TWPE (lb-eq/yr)
011000030304 Niantic River 945,155
050200030309 West Run-Monongahela River 162,780
051402011203 Cowhide Slough-Ohio River 113,838
050302011009 Cow Creek-Ohio River 68,016  Original DMR load is 68,170
050902010601 Crooked Creek-Ohio River 52,120
020801070204 Sarah Creek-York River 43,409
020302030000 Long Island Sound Deep 30,526
040900010307 Bunce Creek-Frontal St. Clair River 22,240
060400050402 Tennessee River-Indian Creek 18,076
041401010603 Mill Creek-Frontal Lake Ontario 17,608

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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 L L C LONG BEACH, CA 4911 180701060600 Cadmium 3,220,760
CA0001139 AES ALAMITOS L L C LONG BEACH, CA 4911 180701060600 Copper 2,250,198
CA0001139 AES ALAMITOS L L C LONG BEACH, CA 4911 180701060600 Zinc 2,016,626
SC0002925 CP&L ROBINSON PLANT HARTSVILLE, SC 4911 030402010606 Cadmium 1,433,716
CT0003263 MILLSTONE NUCLEAR POWER STATION WATERFORD, CT 4911 011000030304 Hydrazine 927,786
CA0001139 AES ALAMITOS L L C LONG BEACH, CA 4911 180701060600 Arsenic 781,488
CA0001139 AES ALAMITOS L L C LONG BEACH, CA 4911 180701060600 Lead 547,596
CA0108073 SOUTHERN CALIFORNIA EDISON COMPANY SAN CLEMENTE, CA 4911 180703010303 Arsenic 524,823
CA0108181 SOUTHERN CALIFORNIA EDISON SAN CLEMENTE, CA 4911 Arsenic 481,266
CA0108073 SOUTHERN CALIFORNIA EDISON COMPANY SAN CLEMENTE, CA 4911 180703010303 Selenium 348,524

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