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Chapter 7 Special Mgmt. Areas Brownfields Domenic Rocco, P. E. , CPESC PA DEP – SERO Chief, Permits and Technical Services PA SWM BMP Manual Pilot Training Split Rock, Carbon County
Agenda: • • • Brownfields Lingo Misconceptions Background What’s changed? Permitting for Brownfield Sites Specific Conflicts – E&S – PCSWM • Example Site • Recommendations • Next Steps
Brownfield Lingo & Misconceptions: • Brownfield are realand Environmental Remediation property, the expansion, • Act 2 - The Land Recycling Standards Act of 1995 redevelopment , or reuse of which may be • Act 2 is a voluntary program. complicated Intentthe presence or potential • NIR – Notice of by to Remediate presence of cleanup does not mean the site will be • A brownfield hazardous substances, pollutants afterwards. or “clean” involve a “cap” to isolate contamination. contaminants. (Source: EPA) – May • Not all Clean-ups go through Act 2*. – Ex. Superfund • Not all sites qualify for Act 2*. • Not all brownfield sites that go through Act 2 require a physical cleanup. – no earth disturbance (for cleanup phase) – “Release of Liability” Protection • “Soil Mgmt Plan” does not cover E&S
Brownfield Lingo & Misconceptions: • Brownfield • Act 2 - The Land Recycling and Environmental Remediation Standards Act of 1995 – Act 2 is a voluntary program. • NIR – Notice of Intent to Remediate • A brownfield cleanup does not mean the site will be “clean” afterwards. – May involve a “cap” to isolate contamination. • Not all Clean-ups go through Act 2*. – Ex. Superfund • Not all sites qualify for Act 2*. • Not all brownfield sites that go through Act 2 require a physical cleanup. – no earth disturbance (for cleanup phase) – “Release of Liability” Protection • “Soil Mgmt Plan” does not cover E&S
Background: • Brownfield projects have become a significant portion of the NPDES workload. (SERO > 40%)* • Brownfields are common in urbanized areas and along old industrial corridors* – rivers, canals and railroads. • Pre – 2005: Permits not needed for brownfield cleanups under Act 2. – Many problems encountered with clean up w/ improper E&S Controls – Citizen complaints – Finger pointing • Full Circle: Different interpretation of existing rules.
What’s changed? • Brownfield sites under Act 2 now require NPDES Permits – Clean up – Redevelopment Both need NPDES permits • In many cases, Individual Permits required. – Potential to discharge chemicals, solvents or other hazardous waste. • Levels of Contamination: PAG-2 – Residential Statewide Health Standard – Non-Residential Statewide HS Indiv. Permit – Background Standard (GW) – Site Specific Standard • Act 2 NIR Letters now reflect these changes. • Cleanups under Superfund are still exempt from NPDES Permits (permit equiv) • PA SWM BMP Manual has section on Brownfields - (Section 7. 2) – Future: Expect to see new BMPs or changes to existing BMPs for Brownfield Sites. *
Permitting for Brownfield Sites: Brownfields Clean-up Consultant Contractor Communication Redevelop. ? Consultant Lead? Contractor
Permit Reviews: • Require a great deal of coordination • Internal Coordination: – Brownfields & Cleanups are not just Act 2 • Act 2 – ECP/Special Projects • Superfund – ECP/HSCA • Ag Orchard – Waste Management – “Addressing Pesticide Contamination on Agricultural Land Proposed for Development” • Other clean up – Waste Management • External Coordination: • Cleanup Consultant/Contractor • Redevelopment Consultant/Contractor • Owner/Applicant
Site Constraints: Brownfields Site Characterization • Contaminant Sources • Transport Mechanisms – Soil – Groundwater – Surface Water Remedial Decision: • • Monitored Natural Attenuation In-Situ Capping Dredging & Excavation (Soil) Pump & Treat (GW) • Exposure Pathways – Receptors • Human • Ecological Potential for Sediment Mobility
Risk Assessment? • Risk-based approach • E&S Program deals with both direct pollution and potential pollution • Applicant needs to convince Plan Reviewer(s) that the risk associated with a contaminated discharge has been abated to a level protective of human health and/or the environment.
Provide a detailed written description of the project. If phases, describe amount of disturbance in first phase and the planned disturbance in each subsequent phase. Application Form 1 Remediation 50 10 04/2007 06/2007 2 Redevelopment 50 40 07/2007 07/2009 Details - Dominant land use for the 5 years preceding the planned project. Details – land uses for the past 50 years, or longer if known. Heavy Metals (Lead) 1. 2 mg/Kg Foundation Soil VOC’s (Benzene) UST Groundwater See Attached 07/03 (12) 8/04 (2) See Attached
E&S Conflicts: • Pollutants of Concern? – VOC’s (Benzene), Heavy Metals (Lead, Arsenic) • Application asks for potential pollutants – Section rarely completed correctly. * – How to disseminate info once received? • What contaminant levels pose a concern? • How are contaminants transported? – – Suspended or in-solution? Can conventional E&S BMPs do the job? What additional BMPs are needed? Information needs to be presented in “plain language”. • Conflicts with Redevelopment activities: – Basin/Trap/Swale – Building foundation – Utility lines!!
Typical E&S Mechanisms • GOAL – to prevent a discharge from a contaminated area. • Avoid/Minimize/Protect (Erosion Control) • Settling (Sedimentation Control) • Filtration (Sedimentation Control)
Erosion Control Structural (Stabilization) Non-Structural – Temporary • Minimize Disturbance • Mats/Blankets/Linings • Seasonal Restriction • Mulching • Phasing • Vegetation • Construction Sequence – Permanent • Vegetation • Imperviousness
Sedimentation Control • Settling – – Silt Fence Compost Berms* Traps Basins • Filtration – – – Compost “Filter” Berms* Rock Filters/Inlet protection Filter socks* Filter bags (pumping) Flocculants (PAM)* Source: EPA • Isolate, Collect and Dispose – Berms – Sumps – Small areas - $$$ Source: Terra Tubes
Compost Berms Compost Socks Compost Blanket
THE USE OF COMPOST AS AN EROSION AND SEDIMENT CONTROL BEST MANAGEMENT PRACTICE MATERIAL Compost shall be a well decomposed, weed free organic matter derived from agricultural, food, and yard or wood/bark organic matter source. The compost must be aerobically composted at a Pennsylvania Department of Environmental Protection (DEP), Bureau of Waste Management permitted site. The compost shall possess no objectionable odors and will be reasonably free (<1% by dry weight) of man-made foreign matter. The compost product shall not resemble the raw material from which it was derived. The physical parameters of the compost should be: p. H 5. 5 – 8. 0 Pg. 136 a in PA E&S Manual Moisture Content 35% - 55% Particle Size 98% pass through 1” screen Soluble Salt Concentration 5. 0 d. S Maximum COMPOST FOR EROSION CONTROL Compost shall be uniformly applied at a rate of 270 – 540 cubic yards per acre (2 to 4 inch layer) to slopes of up to 2: 1. Slopes with problem soils and more runoff will require greater application rates. On highly unstable soils, use compost in conjunction with appropriate structural measures. Spread the compost uniformly, then track (compact) the compost layer using a bulldozer or other appropriate equipment. Alternatively, apply compost using a pneumatic (blower) unit. Project compost directly at soil, thereby preventing water from moving between the soil-compost interface. Apply compost layer approximately 3 feet over the top of the slope or overlap it into existing vegetation. Follow by seeding or ornamental planting. Where planning immediate grass, wildflower, or legume seeding or ornamental planting, use only a well composted product that contains no substances toxic to plants. Very coarse composts should be avoided if the slope is to be landscaped or seeded, as it will make planting and crop establishment more difficult. Composts containing fibrous particles that range in size produce a more stable mat. COMPOST FILTER BERMS Compost may also be used to construct a filter berm for sediment control. Composts denser in nature and containing particles that range in size produce the most stable berms. Do not use compost filter berms in channels. Construct a 1 ½ to 2 foot high by 2. 5 to 3 foot wide berm of compost parallel to the base of the slope or other affected area. For maximum water filtration ability, construct a 1 ½ to 2 foot high trapezoidal berm which is 3 feet wide at the top and 4 feet wide at the
Other E&S measures • Anionic Polyacrylamide Flocculants (PAM) • Alternate Daily Cover products. – Posi-shell – Large stockpiles Site Specific blends Technology from Landfills
PCSWM Conflicts: • What areas are suitable for infiltration? – Area of historic fill and industrial use • Train yard • Incinerator • Manufacturing facility • Where are the known “hot spots”? – Usually doesn’t cover entire site. • What is the contingency plan in the event unexpected contamination is uncovered? • Avoid Redevelopment/Cleanup Overlap
Typical PCSWM Mechanisms BMPs: • Structural • Non Structural Function: • Volume Control ? • Water Quality • Channel Protection • Flood Control
Which PCSWM BMPs? • Non Structural – Reducing ED/Imperv. – Disconnecting Imperv. – “Greening” things up • Structural – Water Quality • Bioretention – Utilize Parking Islands • WQ Inserts/Inlets – Green Roofs – Capture & Reuse • Cisterns – Restoration BMPs • Riparian, Landscape, Soil Amend, Floodplain – Infiltration still viable outside of hot areas.
Example Site: E&S Control Plan Non-Structural • Supplemental Notes – Site Preparation HOT SPOTS – General Notes – Maintenance EXCERPTS: • Construction Sequence DURING EXPOSURE, TEMPORARY DIVERSION BERMS WILL BE INSTALLED TO DIVERT WATER AROUND IMPACTED AREA. PCSWM Plan ANY QUESTIONABLE MATERIAL ENCOUNTERED WILL BE STAGED ON Non-Structural PLASTIC SHEETS WITH FILTER BERMS…. Heavy Metals Typically, no additional FREE WATER IN IMPACTED AREAS WILL BE COLLECTED FOR DISPOSAL. vicinity • Avoid Infiltration in runoff from clean up so VOCs SPECIAL CARE WILL BE TAKEN TO MINIMIZE EXPOSURE DURING of hot spots. no PCSWM needed until DEMOLITION PHASE TO AVOID DISCHARGES OF CONTAMINANTS… redevelopment • Sequence/Notes ENVIRONMENTAL MONITOR SHALL TEST UNDERLYING SOILS TO • In H. S. CONFIRM ATTAINMENT OF STATEWIDE RESIDENTIALsome cases, follow normal protocols.
Example Site: E&S BMPs Compared with Silt Fence: • Better performance* • Less maintenance headaches • Some can be left in place
Recommendations: • Complete Application: – Potential Pollutants– Table A. 8 – Identify Hot Spots on Site Plans Good Site Characterization is critical – Permit Coordination - Section G • ECP/Waste Reviewers & any tracking number. • Full disclosure – What’s on the site? – How are all “concerns” being addressed • Unless “hot spots” are out of the proposed development area, redevelopment should wait until clean up is completed. • Thinking out of the box: – BMP Selection – beyond the “typical” – Plan Notes and Construction Sequencing are major tools.
Next Steps: • Update the application and instructions. • Public Education – Create Fact Sheets – Outreach • Possibly create a new GP for “low risk” brownfield clean-ups. • Update Guidance – E&S Pollution Control Manual – SWM BMP Manual • Share info and learn from each other. - FIN -