tailieunhanh - The department of Pesticide Regulation

Organic crops must be protected from potential contamination by adjoining conventional farms, as well as from non-organic fields in split operations. The drift and run-off of prohibited substances, as well as the pollen drift from GMO varieties, can compromise the farm’s organic certification status. The certifying agency can require water, soil, and plant testing in cases where contamination is suspected. Preventative strategies include the use of buffer zones and barriers, altering drainage patterns, posting “no spray” signs, and cooperating with neighboring conventional farmers. Growers with split operations must take additional steps to prevent the commingling of. | c pr Department of Pesticide Regulation Mary-Ann Warmerdam Director M E M O R A N D U M Edmund G. Brown Jr. Governor TO Randy Segawa Environmental Program Manager I Environmental Monitoring Branch Original signed by Frank Spurlock FROM Daniel R. Oros . for Environmental Scientist Environmental Monitoring Branch Frank C. Spurlock . Original signed by Research Scientist III Environmental Monitoring Branch 916-324-4124 DATE January 28 2011 SUBJECT ESTIMATING PESTICIDE PRODUCT VOLATILE ORGANIC COMPOUND OZONE REACTIVITY. PART 2 REACTIVITY-WEIGHTED EMISSIONS ABSTRACT In this memorandum we a describe a procedure for estimating ozone O3 formation potential of pesticide products b compare 1990 and 2007 ozone season pesticide O3 formation potentials in the San Joaquin Valley SJV c compare the relative contribution of individual product components to SJV O3 formation potentials d compare the relative contribution of different products to SJV O3 formation potentials and e compare SJV O3 formation potentials based on both the maximum incremental reactivity MIR and equal benefit incremental reactivity EBIR scales. As used here ozone formation potential OFP does not refer to actual O3 produced but is instead a relative measure of reactivity-weighted mass Volatile Organic Compound VOC emissions. Note A full listing of all acronyms is given in Appendix 1 at the end of this paper. Although SJV VOC mass emissions were approximately 15 lower in 2007 than 1990 differences were smaller for total ozone season SJV OFPs as determined on either the MIR or EBIR scales. In 1990 the estimated MIR OFP was tons per day O3 equivalents tpdoe and the EBIR OFP was tpdoe. In 2007 the MIR OFP was tpdoe while the EBIR OFP was tpdoe. Nonfumigant products were greater contributors to total SJV OFP in both years than fumigants. The estimated nonfumigant product OFP contribution was and tpdoe MIR basis and and tpdoe EBIR basis in 1990 and 2007 respectively. .