I am an organic farmer and have been since 1993. I am also a conventional farmer and have been growing biotech crops since 1998. No organic farmer has ever lost his certification due to inadvertent GMO presence in their crop. The federal National Organic Program – NOP – has stated that as long as the organic grower did not intentionally use “excluded methods” i.e. GMO seed is an excluded method in organic production, that a grower will not lose their organic certification. So unless an organic grower intentionally plants a crop with GMO traits, the certification of their organic land and crops will not be affected.
If GMO traits are found in the organic farmers crop, it is usually up to the buyer of the crop to accept or reject his product based on their contract specifications which does allow for a certain percentage of GMO traits to be present. Organic certification does not equal zero presence of a GMO trait. Low-level presence of a GMO trait in organic production is allowed as long as the grower has followed the organic process necessary for organic production.
There are many ways to have a GMO trait appear in an organic crop other than pollen drift from a nearby neighbor. The planting seed may have been mixed with biotech trait seed, the planter, harvesting equipment, trucks or storage facility may not have been cleaned properly. Pollen from a neighbor is only one of many ways that can affect an organic grower. Organic crops with GMO presence can and are sold as organic; the USDA organic certification does not have a zero policy.
There are different buyers with different contract specifications available to a grower. If for some reason the organic crop could not be sold as organic, it could be sold into the conventional market.
As an organic grower I communicate with my neighbors and use different planting dates or separation to avoid pollination from any surrounding crops whether from my own biotech crops or those of my neighbors. We choose to grow different crops with different cropping systems, organic, conventional and biotech, all on the same farm and without issues of pollen flow from one to the other.