1. Why Metrics Matter: Prioritizing Strategies for Measuring and Managing Reactive Nitrogen in the San Joaquin Valley Ariel Horowitz, William R. Moomaw, Dan Liptzin, Benjamin Gramig, Carson Reeling, Johanna Meyer, and Kathleen Hurley Tufts university Fletcher School of International Law and Diplomacy University of California – Davis Purdue University Western Michigan University 10/03/2015HOROWITZ 1

2. Outline o Introduction o Current approaches to managing nitrogen in the United States o Nitrogen in the San Joaquin Valley o Multiple metrics approach o Implications arising from use of multiple metrics o Conclusions 10/03/2015HOROWITZ 2

3. Impacts of reactive nitrogen o Health impacts o Respiratory (NO x ) o Colon cancer (NO 3 - ) o Biodiversity loss o Acid rain o Climate change (N 2 O) o N saturation 10/03/2015HOROWITZ 3 http://www.stockholmresilience.org/21/research/research-programmes/planetary-boundaries.html

4. Study area San Joaquin and Tulare hydrological regions One of the most agriculturally-intensive areas of the world! 10/03/2015HOROWITZ 4

5. Current regulation of nitrogen in the USA o Clean Air Act o Regulates emissions o NO X (criteria pollutant) o NH 4 o Ammonium nitrate particulates o Clean Water and Safe Drinking Water Acts o Regulates concentrations o Nitrate o No regulation based on damages caused! 10/03/2015HOROWITZ 5

6. Nitrogen flows Shown in tonnes/year Croplands Leaching 200,000 Croplands Leaching 200,000 Runoff 43,000 (Incl. 29,000 from crops) Runoff 43,000 (Incl. 29,000 from crops) Fertilizer 300,000 Fertilizer 300,000 Dairies - Leaching 11,000 Dairies - Leaching 11,000 Dairies - Volatilization NH x – 120,000 N 2 O – 1600 Dairies - Volatilization NH x – 120,000 N 2 O – 1600 Harvested Crops 280,000 Harvested Crops 280,000 Stationary Emissions NH x – 30,000 NO x – 13,000 N 2 O – N.E. Stationary Emissions NH x – 30,000 NO x – 13,000 N 2 O – N.E. Mobile Emissions NH x – 2400 NO x – 53,000 N 2 O – N.E. Mobile Emissions NH x – 2400 NO x – 53,000 N 2 O – N.E. N 2 Fixation 130,000 (Incl. 100,000 to crops) N 2 Fixation 130,000 (Incl. 100,000 to crops) Deposition to Land NH x – 28,000 OxN – 34,000 Deposition to Land NH x – 28,000 OxN – 34,000 Deposition to Water NH x – 340 OxN – 610 Deposition to Water NH x – 340 OxN – 610 Dairies - Manure 190,000 Dairies - Manure 190,000 Wastewater Treatment N 2 – 1500 N 2 O – 10 NO 3 - (ground) – 7100 NO 3 - (surface) – 5500 Biosolids – 1700 Wastewater Treatment N 2 – 1500 N 2 O – 10 NO 3 - (ground) – 7100 NO 3 - (surface) – 5500 Biosolids – 1700 Septic System Leaching 3700 Septic System Leaching 3700 Soil Emissions NH x – 61,000 NO x – 16,000 N 2 O – 6100 N 2 – 3600 Soil Emissions NH x – 61,000 NO x – 16,000 N 2 O – 6100 N 2 – 3600 10/03/2015HOROWITZ 6 N 2 /non-reactive Oxidized N NH x N2ON2O

7. Nitrogen damages Shown in $1000/year Croplands Leaching $500,000 Croplands Leaching $500,000 Runoff $120,000 (Incl. $87,000 from crops) Runoff $120,000 (Incl. $87,000 from crops) Fertilizer N.E. Fertilizer N.E. Dairies - Leaching $30,000 Dairies - Leaching $30,000 Dairies - Volatilization NH x – $490,000 N 2 O – $24,000 Dairies - Volatilization NH x – $490,000 N 2 O – $24,000 Harvested Crops N.E. Harvested Crops N.E. Stationary Emissions NH x – $300,000 NO x – $170,000 N 2 O – N.E. Stationary Emissions NH x – $300,000 NO x – $170,000 N 2 O – N.E. N 2 Fixation N.E. N 2 Fixation N.E. Deposition to Land NH x – $220,000 OxN – $270,000 Deposition to Land NH x – $220,000 OxN – $270,000 Deposition to Water NH x – $1600 OxN –$2300 Deposition to Water NH x – $1600 OxN –$2300 Dairies - Manure N.E. Dairies - Manure N.E. Wastewater Treatment N 2 – N.E. N 2 O – $150 NO 3 - (ground) – $19,000 NO 3 - (surface) – $14,000 Biosolids – N.E. Wastewater Treatment N 2 – N.E. N 2 O – $150 NO 3 - (ground) – $19,000 NO 3 - (surface) – $14,000 Biosolids – N.E. Septic System Leaching $9600 Septic System Leaching $9600 Mobile Emissions NH x – $340,000 NO x – $1,500,000 N 2 O – N.E. Mobile Emissions NH x – $340,000 NO x – $1,500,000 N 2 O – N.E. Soil Emissions NH x – $360,000 NO x – $220,000 N 2 O – $91,000 N 2 – N.E. Soil Emissions NH x – $360,000 NO x – $220,000 N 2 O – $91,000 N 2 – N.E. 10/03/2015HOROWITZ 7 N 2 /non-reactive Oxidized N NH x N2ON2O

8. Different metrics suggest different actions Top 5 flows by MASS: 1.Fertilizer 2.Crop export 3.Leaching from croplands 4.Manure from dairies 5.NH 3 volatilized from dairies Top 5 flows by DAMAGE: 1.Mobile NO x 2.Leaching from croplands 3.NH 3 volatilized from dairies 4.Atmospheric deposition 5.Mobile NH 3 10/03/2015HOROWITZ 8

9. Flows and damages are both localized! 10/03/2015HOROWITZ 9

10. Use of Nr leads to concentrated burdens o Damage costs are extremely geographically- specific o Health damage cost due to tailpipe NO x conversion to PM2.5 in San Joaquin Valley: $22.74/kg o Health damage cost due to tailpipe NO x conversion to PM2.5 in Chesapeake Bay: $15.83/kg o Some damages are known but unpriced o Biodiversity loss o N saturation o Damaged quality of life o Benefits of Nr use are distributed; costs are concentrated! 10/03/2015HOROWITZ 10

11. Conclusions o A unified strategy is needed to measure and manage Nr in all its forms o Mass- and concentration-based regulations do not consider how damage varies by source o Damage costs are extremely geographically-specific o Health effects dominate damage costs o Using a combination of damage costs and abatement costs can identify cost effective mitigation options o Multiple metrics approach combined with improved monitoring will increase the effectiveness of policies and actions for managing Nr 10/03/2015HOROWITZ 11

12. Thank you! Questions? WE GRATEFULLY ACKNOWLEDGE SUPPORT FROM THE DAVID AND LUCILE PACKARD FOUNDATION, THE NETHERLANDS MINISTRY OF ECONOMIC AFFAIRS, AND THE US DEPARTMENT OF AGRICULTURE NATIONAL INSTITUTE OF FOOD AND AGRICULTURE (NIFA) HATCH PROJECT W-3133. 10/03/2015HOROWITZ 12

13. Damage flows Source of NrDamage Cost ($/kg) Atmospheric Emissions HEALTH EFFECTS Mobile NO x a 22.74 Nonmobile NO x a 7.39 Mobile NH 3 a 140.36 Dairy and fertilizer NH 3 a 3.02 Nonmobile NH 3 a 9.18 Biome NH 3 a 17.01 OTHER COSTS Reduced visibility 4 0.31 Crop declines from ozone (NO x only) 4 1.51 Forest declines from ozone (NO x only) 4 0.89 N 2 O - UV Damage 4 1.33 N 2 O - Climate Change13.52 Aqueous Nitrate treatment in wells 4 0.16 Colon cancer due to nitrate in wells 4 1.76 Undesirable taste 9 0.14 Nitrate contamination 9 0.54 From Deposition Damage to buildings from acidification (NO x only) 4 0.09 Loss of plant biodiversity from N enrichment 9 7.73 Deposition of NO x b 3.27 Deposition of NH 3 b 0.62 10/03/2015HOROWITZ 13

14. Emissions (2008 NEI) of secondary PM 2.5 in the SJV Nitrate Mobile sources Classification of source categories Stationary sources Allocation of secondary PM 2.5 Ammonium ion from Nitrate Ammonium ion from sulfate Sulfate Reduction in PM 2.5 from eliminating NO 3 - flow (Table S1) Source apportionment based on air quality model in Ying and Kleeman (2006) EPA BenMap model Health impacts Economic damages N r Chemical Cascade N r Damage Cascade