TPDES Stormwater Annual Report FY2019 | Page 22

V .
MS4 Screening and Illicit Discharge Inspections
The City of Arlington has implemented a Dry Weather Screening and Monthly Routine Screening program to locate portions of the MS4 with suspected illicit discharges and improper disposals . Results of screening efforts during this permit term as well as a more complete description of the program may be found in MCM 8 , Monitoring , Evaluation , and Reporting . The entire MS4 , but not necessarily each individual outfall , is screened at least once during the five-year permit term .
VI .
NPDES and TPDES Permittee List
The City of Arlington maintains an industrial and construction database containing a list of operators and construction sites that are located within the Arlington city limits . This database contains the name , location , and permit number ( when applicable ) that authorizes stormwater discharges from construction activities .
VII .
MS4 Map
The City of Arlington presently operates a system with approximately 3,610 storm sewer outfalls , 607 miles of storm sewer pipe , and about 19,426 inlets . In the previous permit term , the City implemented an asset identification and inventory program to track all MS4 assets . Unique identifiers are assigned to allow for efficient tracking of system conditions , inspections , and maintenance . The system is GIS based and integrates system inventory data into a system map . Outfall verifications , inlet and manhole locations , and storm sewer pipe identification are continuous activities .
VIII .
Spill Prevention and Response
The Hazardous Materials Response Team ( HMRT ) of the City ’ s Fire Department and Environmental Specialists provide spill response for hazardous material spills . The HMRT provides initial response and containment , while Environmental Specialists ensure removal of the spilled material in a manner that protects water quality . If the spill is minor ( i . e . is not of reportable quantity ), the HMRT will respond and perform the necessary removal actions themselves . There were no changes to the hazardous material spill response procedures during FY18 .
During the 3-IRP , the HMRT expended over 325 man-hours responding to 434 HAZMAT incidents . These are outlined below .
Type of Response
Number of Responses
Hazardous condition , other
87
Combustible / flammable gas / liquid condition , other
6
Gasoline or other flammable liquid spill
33
Gas leaks
246
Oil or other combustible liquid spill
8
Chemical hazards ( Chemical spill or leak )
9
Refrigeration leaks
3
Carbon Monoxide Incidents
33
Total
434
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