A Discussion of Cumulative Impacts

1. A Discussion of Cumulative Impacts Presented By Krishnan Ramamurthy and Michael A. Corbin

2. Overview • Starting from Common Ground • Language/terms • Understanding Current DEP Program (air, waste, water and mining) Authority for Cumulative Impacts • Agreeing to Common Goals • When should we use Cumulative Impacts Analysis • External Work Group recommendations related to sources and/or areas • How should we implement Cumulative Impacts Analysis

3. Starting from Common Ground • Language/terms • National Environmental Policy Act definition of Cumulative Impact -”Cumulative impact” is the impact on the environment which results from the incremental impact of the action when added to other past, present, and reasonably foreseeable future actions.... Cumulative impacts can result from individually minor but collectively significant actions taking place over a period of time. See 40 CFR 1508.7.

4. Starting from Common Ground • Language/terms • Cumulative Risk Assessment - involves the consideration of the aggregate ecological or human health risk to the target entity (i.e., maximum exposed individual ) caused by the accumulation of risk from multiple stressors such as multiple pathways and multiple sources. The environmental stressors may include, but are not limited to, radiation, microbiological agents, chemicals, vibrations, traffic congestion, and noise pollution. • Additive effect - Combined effect of two chemicals is equal to the sum of the effect of each chemical alone. (1+1 =2)

5. Starting from Common Ground • Background - Cumulative risk assessments are typically performed to assess the aggregated risks from various pollutants released at a single facility through either a route of exposure (inhalation) or multiple routes of exposure, which include inhalation, soil ingestion and food intakes. The cumulative assessment, in theory, could include the effect of synergism and antagonism. However, synergistic and antagonistic effects cannot be quantified at present. The additive effects are included in the assessment. For example, the carcinogenic effects of various chemicals are added to represent the total potential cancer risks.

6. Starting from Common Ground • There are other methods, aside from cumulative risk assessments, that can be used to determine cumulative impacts such as the number of facilities in an area and the volume of activity or discharge and the resulting effect on the surrounding area. Similarly, cumulative exposures from multiple facilities can be modeled and compared to existing health based standards.

7. Starting from Common Ground • Various versions of cumulative risk assessments - • Single Point Source - Single Medium (typically inhalation) Various Pollutants • Multiple Point Sources - Single Medium - Various Pollutants • Multiple Sources including point, non-road, highway and area - Single Medium - Various Pollutants • Point - factories, power plants, refineries • Non-road - mowers, tractors, ATV’s • Highway - cars, trucks, buses • Area - wood-stoves, fireplaces, dry cleaners, gas stations

8. Starting from Common Ground • Various versions of cumulative risk assessments - • Single Point Source -Multi -Media - Various Pollutants • Multiple Point Sources- Multi-Media - Various Pollutants • Multiple Sources - Multi - Media - Various Pollutants • Note: It is progressively more complicated and intensive as you consider more sources, media and pollutants.

9. Starting from Common Ground • Focus on: • Cumulative Risk Assessment • Additive effect • Other impacts (i.e. number of facilities or volume of activities)

10. Starting from Common Ground • Understanding Current DEP Program (air, waste, water and mining) Authority for Cumulative Impacts • The forgoing list is not intended to be an exhaustive list of all of the Department's authority to conduct cumulative impact analysis. Rather it is intended to highlight the clearest examples of that authority. • Air Quality. “40 C.F.R. § 51.166 (Prevention of significant deterioration of air quality), as incorporated by 25 Pa. Code § 127.81: Requires modeling of point sources of criteria pollutants for new construction and modifications of major air sources in attainment areas. The Department may not issue a plan approval if the resulting emissions from the new or modified air source will cause an exceedance of National Ambient Air Quality Standards (NAAQS)."

11. Starting from Common Ground • Water Quality - • 25 Pa. Code § 92.81 (General NPDES permits): Authorizes the Department to issue General NPDES permits for point sources which "individually and cumulatively do not have the potential to cause significant adverse environmental impact." • 25 Pa. Code § 105.18a (Permitting of structures and activities in wetlands): Prohibits the Department from granting a permit for a dam, water obstruction or encroachment in or around exceptional value wetlands unless the applicant demonstrates that the "cumulative effect of the project and other projects will not result in impairment of the Commonwealth's exceptional value wetland resources." Cumulative effects are also a permitting factor for other types of wetlands. See also 25 Pa. Code § 105.14.

12. Starting from Common Ground • Water Quality Continued • Valley Creek Coalition v. DEP, Docket No. 98-228-MG (December 15, 1999): Environmental Hearing Board stated that Department should consider cumulative effect of discharges in exceptional value waters. • Proposed Regulation: 25 Pa. Code § 96.4 (TMDLs): Would require the Department to develop Total Maximum Daily Loads (TMDLs) for impaired watersheds.

13. Starting from Common Ground • Mining • 35 P.S. § 691.315 (Operation of mines): Requires mining applicants to include sufficient information in applications for the Department to make an assessment "of the probable cumulative impacts of all anticipated mining in the area upon the hydrology of the area and particularly upon water availability." • 25 Pa. Code § 86.37 (Criteria for permit approval or denial): Prohibits the Department from approving a permit for coal mining unless an assessment of probable cumulative impacts of all anticipated mining in the general area of the hydrologic balance has been made by the Department and the activities proposed have been designed to prevent material damage to the hydrologic balance outside the proposed permit area.

14. Agreeing to Common Goals • When should DEP use Cumulative Impacts Analysis to address concerns in minority and low-income communities? • The Environmental Justice Work Group recommended the following: • Demographics. 30% minority population and/or 20% low-income population. • Trigger permits • Opt-in situations. • Should DEP consider other factors such as: • Number of facilities. • Health

15. Agreeing to Common Goals • What are EJAB’s cumulative Impact Analysis recommendations. • What factors should we consider when conducting the Cumulative Impacts Analysis in minority and low-income areas? • Should we also consider recommendations beyond cumulative risk, i.e. number of exposures, number of facilities (clustering) and volume of activities? • How should we implement Cumulative Impacts Analysis • EJAB should consider recommending that DEP and the Cumulative Impacts Subcommittee report back to the EJAB with a detail proposal on the implementation of Cumulative Impacts Analysis.

16. Agreeing to Common Goals • Coming to terms with authority issues. • What, if any, additional authority is needed to implement a proposed cumulative impacts analysis. • Policy • Regulation • Statute

17. Agreeing to Common Goals • What is the process? • Policy. Is there a need for a cumulative impact screening process? . • Regulation. • Statute. • How do we develop a detail methodology to conduct a cumulative impact analysis. • What are the time factors for each of the above?

18. Conclusion • The DEP Internal Work Group and the Cumulative Impacts Subcommittee should work to address this issue and report back to EJAB. • DEP and EJAB should develop a reasonable and flexible plan to address this complex issue.