UNITED STATES ENVIRONMENTAL PROTECTION AGENCY Region 1 S Post Office Square, Suite 100 BOSTON, MA 02109-3912 CERTIFIED MAIL RETURN RECEIPT REQUESTED APR 0 1 2015 Mr. William McGuiness Senior Project Manager White Skanska Kiewit, N 200 lnnerbelt Rd. Somerville, MA 02143 Re: Authorization to discharge under the Remediation General Permit (RGP) ­ MAG910000. Green Line Extension I Commuter Rail Maintenance Facility Access Road site located at 200 Innerbelt Road, Somerville, MA 02143, Middlesex County; Authorization# MAG910671 Dear Mr. McGuiness: Based on the review ofa Notice ofIntent (NOI) submitted by Frank Ricciardi, from Weston & Sampson., on behalf of your company White Skanska Kiewit, N , for the site referenced above, the U.S. Environmental Protection Agency (EPA) hereby authorizes you, as the named Operator, to discharge in accordance with the provisions ofthe RGP at that site. Your authorization number is listed above. The checklist enclosed with this RGP authorization indicates the pollutants which you are required to monitor. Also indicated on the checklist are the effluent limits, test methods and minimum levels (MLs) for each pollutant. Please note that the checklist does not represent the complete requirements ofthe RGP. Operators must comply with all ofthe applicable requirements ofthis permit, including influent and effluent monitoring, narrative water quality standards, record keeping, and reporting requirements, found in Parts I and II, and Appendices I - VIII of the RGP. See EPA's website for the complete RGP and other information at: http://www.epa.gov/regionl/npdes/mass.html#dgp. Please note the enclosed checklist includes parameters that your consultant marked "Believed Present" . The checklist also includes other parameters for which your laboratory reports indicated there was insufficient sensitivity to detect these parameters at the minimum levels established in Appendix VI of the RGP. Also, please note that the metals included on the checklist are dilution dependent pollutants and subject to limitations based on a dilution factor range (DFR), due to the ample dilution at the point ofdischarge (97) the DFR applicable for this pollutant is within a dilution range greater than 50 to one hundred (>50-100) established in the RGP. (See the RGP Appendix IV for Massachusetts facilities). Therefore, the limit for arsenic of500 ug/L, copper of 260 ug/L, lead of66 ug/L, nickel of I ,451 , zinc of 1,480 ug/L and iron of5,000 ug/L, shall not be exceeded in the discharge. This general permit and authorization to discharge will expire on September 9, 2015. You have reported that this project will terminate on July 31, 2015. You are required to submit a Notice of Termination (NOT) to the attention of the contact person indicated below within 30 days of project completion. Thank you in advance for your cooperation in this matter. Please contact Victor Alvarez at 617­ 918-1572 or [email protected], ifyou have any quest ions. Sincerely, ·1'J,~ /1~/iu.'( - Thehna Murphy, Chief Storm Water and Construction Permits Section Enclosure cc: Robert Kubit, MassDEP Stanley Coty, Commissioner, Somerville DPW Frank Ricciardi, Weston & Sampson 2 2010 Remediation General Permit Summary of Monitoring Parametersill NPDES Authorization Number: MAG910671 Authorization Issued: March 2015 FacilityjSite Name: Green Line Extension/Commuter Rail Maintenance Facilit'_Access 200 Innerbelt Road, Somerville, MA 02143 Facility/Site Address: Email address of owner: [email protected] Legal Name of Operator: White Skanska Kiewit, JV Mr. William McGuiness, Senior Project Manager, 200 Innerbelt Operator contact name, title, Rd. Somerville, MA 02143 and Address: Email: Williammcauiness\alskanska.com Estimated date of the site's Completion: ISeptember 31 2015 Category III- Contaminated Construction Dewatering. Category and Sub-Category: Subcategory A. & B. General Urban Fill sites and Known Contaminated Sites, respectively. RGP Termination Date: September 10, 2015 Receiving Water: Miller River Monitoring & Limits are applicable if checked. All samples are to be collected as grab samples Effluent LimitlMethod#lML (All Effluent Limits are shown as Daily Parameter Maximum Limit, unless denoted by a **, in that case it will be a Monthly Average Limit) ..; 1. Total Suspended Solids 30 milligrams/liter (mg/L) **, SO mg/L for (TSS) hydrostatic testing** Me#160.2/ML5ug/L ..; 2. Total Residual Chlorine Freshwater= 11 ug/L ** Saltwater = (T'RC) 1 7.5 ug/L **/ Me#330.5_LML 20u_gll 3. Total Petroleum ..; 5.0 mg/L/ Me# 1664A/ML S.Omg/L Hydrocarbons (TPH) 2 3 Freshwater = 5.2 ug/1 ** Saltwater = 1.0 ..; 4. Cyanide (CN) • ug/L **L Me#335.4/ML 10UQ/L Sug/L /50.0 ug/L for hydrostatic testing 5. Benzene (B) only/ Me#8260C/ML 2 ug/L (limited as ug/L total BTEX)/ Me#8260C/ 6. Toluene (T) ML 2ug/L (limited as ug/L total BTEX) Me#8260C/ 7. Ethylbenzene (E) ML 2ug/L 8. (m,p,o) Xylenes (X) _(limited as ug/L total BTEXj_ Me#8260C/ 3 Effluent LimitlMethod#lML (All Effluent Limits are shown as Daily Parameter Maximum Limit, unless denoted by a **, in that case it will be a Monthly Average Limit) ML 2ug/L 9. Total Benzene, Toluene, Ethyl Benzene, and Xylenes 100 ug/L/ Me#8260C/ ML 2ug/ L (BTEX) 4 10. Ethylene Dibromide (EDB) 0.05 ug/1/ Me#8260C/ ML 10ug/L (1 2- Dibromoethane) 11. Methyl-tert-Butyl Ether 70.0 ug/I/Me# 8260C/ML 10ug/ L (MtBE) 12.tert-Butyl Alcohol (TBA) Monitor Only(ug/L)/Me# 8260C/ML 10ug/L (TertiarvButanol) 13. tert-Amyl Methyl Ether Monitor Only(ug/ L)/Me# 8260C/ML 10ug/ L (TAME) 14. Naphthalene 5 20 ug/L /Me#8260C/ML 2ug/L 15. Carbon Tetrachloride 4.4 ug/L /Me#8260C/ ML 5ug/L 16. 1,2 Dichlorobenzene (o- 600 ug/ L / Me# 8260C/ ML 5ug/ L DCB) 17. 1,3 Dichlorobenzene ( m- 320 ug/ L /Me# 8260C/ ML 5ug/L DCB) 18. 1,4 Dichlorobenzene (p- 5.0 ug/L /Me#8260C/ ML 5ug/L DCB) 18a. Total dichlorobenzene 763 ug/ L - NH only /Me#8260C/ ML 5ug/L 19. 1,1 Dichloroet hane (DCA) 70 ug/L /Me#8260C/ ML 5ug/L 20. 1,2 Dchloroethane (DCA) 5.0 ug/L /Me#8260C/ ML 5ug/L 21. 1,1 Dichloroethene (DCE) 3.2 ug/L/Me#8260C/ ML 5ug/L 22. cis- 1,2 Dichloroethene 70 ug/ L/Me#8260C/ ML 5ug/L (DCE) 23. Methylene Chloride 4.6 ug/L/Me#8260C/ ML 5ug/L 24. Tetrachloroethene (PCE) 5.0 ug/L/Me#8260C/ ML 5ug/L 25. 1,1,1 Trichloro-ethane 200 ug/ L/Me#8260C/ ML 5ug/L (TCA) 26. 1,1,2 Trichloro-ethane 5.0 ug/L /Me#8260C/ ML 5ug/L (TCA) 27. Trichloroethene (TCE) 5.0 ug/L /Me#8260C/ ML 5ug/L 28. Vinyl Chloride 2.0 ug/ L /Me# 8 260C/ ML 5ug/ L (Chloroethene) 29. Acetone Monitor Only(ug/ L)/Me#8260C/ML 50ug/ L 30. 1,4 Dioxane Monitor On ly /Me#1624C/ML 50ug/L 300 ug/L Me#420.1&420.2/ML 2 ug/L/ 31. Total Phenols Me# 420.4 /ML 50ug/L 1.0 ug/L / Me# 8270D/ ML Sug/ L,Me# 604 32. Pentachlorophenol (PCP) &625/ML 10ug/L y 33. Total Phthalates 3.0 ug/L ** /Me#8270D/ML 5ug/L, (Phthalate esters) 6 Me#606/ML 10ug/L& Me#625/ML 5ug/L 34. Bis ( 2-Ethylhexyl) 6.0 ug/L /Me# 8270D/ML Pht halate [Di­ (ethylhexyl) 5ug/ L,Me# 606/ML 10ug/ L & Me# 625/ ML Phthalate] 5ug/L 4 Effluent LimitlMethod#lML (All Effluent Limits are shown as Daily Parameter ~aximum Limit, unless denoted by a **, m that case it will be a Monthly Average Limit) 35. Total Group I Polycyclic 10.0 ug/L v' Aromatic Hydrocarbons (PAH) 0.0038 ug/L /Me#8270D/ ML Sug/L, a. Benzo(a) Anthracene 7 v' Me#610/ML Sug/L& Me#625/ML Sua/L 0.0038 ug/L /Me#8270D/ ML Sug/L, b. Benzo(a) Pyrene 7 v' Me#610/ML Sug/L& Me#625/ML Sua/L 0.0038 ug/L /Me#8270D/ ML Sug/L, c. Benzo(b)Fiuoranthene 7 v' Me#610/ML SuQ/L& Me#625/ML Sua/L 0.0038 ug/L /Me#8270D/ ML Sug/L, d. Benzo(k)Fiuoranthene 7 v' Me#610/ML Sua/L& Me#625/ML Sua/L 0.0038 ug/L /Me#8270D/ML Sug/L, e. Chrysene 7 v' Me#610/ML Sua/L& Me#625/ML Sua/L 0.0038 ug/L /Me#8270D/ML Sug/L, f . Dibenzo(a,h)anthracene 7 v' Me#610/ML Suo/L& Me#625/ML Sua/L 0.0038 ug/L /Me#8270D/ML Sug/L, g. Indeno(1,2,3-cd) Pyrene 7 v' Me#610/ML Suo/L& Me#625/MLSua/L 36. Total Group II Polycyclic 100 ug/L Aromatic Hydrocarbons (PAH) X/Me#8270D/ML Sug/L,Me#610/ML h. Acenaphthene Sl.lg/L & Me#625/ML Sua/L X/Me#8270D/ML Sug/L,Me#610/ML i. Acenaphthylene Sua/L & Me#625/ML Sua/L X/Me#8270D/ML Sug/L,Me#610/ML j. Ant hracene Sug/L & Me#625/ML Sua/L X/Me#8270D/ML Sug/L,Me#610/ML k. Benzo(ghi) Perylene Sug/L & Me#625/ML Sug/L X/Me#8270D/ML Sug/L,Me#610/ML I. Fluoranthene Sug/L & Me#625/ML Sug/L X/Me#8270D/ML Sug/L,Me#610/ML m. Fluorene Sug/L & Me#625/ML Sua/L 20 ug/1 I Me#8270/ML Sug/L, Me#610/ML n. Naphthalene s Sug/L & Me#625/ML Sug/L X/Me#8270D/ML Sug/L,Me#610/ML o.