Dan, The sources of alkaline etchant should perhaps be judged more by the places where spent alkaline etchant can be reclaimed. We at MacDermid sell and reclaim in the northeast where we have a factory. Your transportation cost will be more a function of where you ship for reclaim, as many states consider spent as hazardous waste, and you will have to deal with manifesting regulations and waste hauler licensees. Most etch suppliers/reclaimers have their own fleet of trucks with hazardous waste licenses for spent. Tranportation costs depend on where you ship the spent etch - at least as much as the source of the fresh. Phibrotech certainly is a major supplier/reclaimer in the Los Angeles area. You can bubble ammonia gas into the sump from anhydrous cylinders. This is what is being lost up the vent system. Or, if your sump turnover is low, try to reduce sump volume with glass bricks. This will turn the sump over more often so that the replenisher cascading in from the recirculating rinses has more effect to raise pH. Denny Fritz MacDermid --------------------------------------------------------------------------------- Technet Mail List provided as a free service by IPC using LISTSERV 1.8d To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt delivery of Technet send the following message: SET Technet NOMAIL Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail Archives Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ---------------------------------------------------------------------------------