var spatialRef = pMap.SpatialReference;
            double calculatedTolerance = 0.0;

            if (spatialRef != null && spatialRef.HasXYPrecision())
            {
                var spRefTolerance = spatialRef as ISpatialReferenceTolerance;
                if (spRefTolerance != null && spRefTolerance.XYToleranceValid == esriSRToleranceEnum.esriSRToleranceOK)
                {
                    calculatedTolerance = spRefTolerance.XYTolerance;
                }
                else
                {
                    calculatedTolerance = -1.0;
                }

            }

            pSpatFlt.Geometry = pTopOp.Buffer(calculatedTolerance);