Natural gas cash prices in West Texas, which dipped below zero in recent days, sank to the lowest in almost 14 months, as traders expect pipeline maintenance in the area to stifle movement of the fuel for some time.Gas for next-day delivery at the Waha hub in the prolific Permian region remained negative Monday although recovered from a multi-month low last week, according to traders familiar with intraday prices, which were not publicly available. Prices Friday fell to around negative $3.03 per million Bri ...