Lethbridge Herald, The (Newspaper) - September 3, 1974, Lethbridge, Alberta
Tuesday, September 3, 1974 LETHBRIDGE HERALD The red-and-white incinerator stack of Shell Canada's Waterton gas plant looms over five pigs and 10 yearling heifers confined almost in the shadow of the 500-foot stack. Although the 15 animals and a nearby grain and hay crop are only a mile downwind of Shell's massive plant, the oil company isn't ex- pecting any complaints about air pollution from the operators of the mini-farm. The operators, in this case, are researchers working for Farm and Ranch Management, an agricultural consulting firm hired by Shell. The mini-farm is part of a unique probe to discover the effects of gas plant emissions on downwind vegetation and livestock. Shell plant officials say that after 30 months, the experiment's results indicate that sulphur dioxide released from the plant into the at- mosphere has little effect on plants and no effect on livestock. Independent Plant manager Cliff Paulson says the results are the product of an independent inquiry. Farm and Ranch, he adds, were given com- plete freedom in locating test sites. Shell also gave Farm and Ranch free reign in reporting research to interested area ranchers. The farm-ranch experiment started in the summer of 1972 as researchers picked six growing sites downwind of the gas plant in known areas of ground-level pollution. Six companion sites out- side the emission zone were chosen for similarity of sunshine-hours, rainfall, exposure and natural foliage. Researchers then planted alfalfa, barley and brome in five-gallon pots at all 12 sites. Identical soil was used and all plants received similar watering and fertilizing. With atmospheric conditions intended to be the major cause of crop variations, researchers repeated pot experiments last summer and again this summer. Results have not been conclusive, says manager Paulson, because the first two summers had such different weather that crops could not be compared. In 1972, alfalfa and barley crops inside the emission area failed to grow as well as their counterparts in clean air. But brome hay yields were txvo per cent higher at emission-zone sites. In 1973, researchers also seeded the three crops on 12 50- by 54-foot plots to simulate farm conditions. The potted crops performed equal- ly well .last summer, with no appreciable difference between emission-zone and control sites. The cereal and forage crops planted in all 12 plots suffered from lack of moisture in 1973. Both pot and plot experiments will be continued until the end of the 1976 crop year, says plant manager Paulson. While crop experiments haven't proved very much of anything, en- vironmental co-ordinator Brad Sawyer says livestock experiments indicate there is no hazard to animals exposed to sulphur emissions. Researchers chose 12 sites to raise mice and commercial broil- ing chickens, with nine sites inside and three sites outside the plant's emission area. In 1972, 40 newly-hatched chicks and 24 female mice took up residence in each of the 12 sites. Subsequent autopsies failed to turn up anything unusual, says Paulson. A rate-of- gain experiment conducted at the same time showed broilers in each location gained weight equally. The chicken experiments were repeated last summer with 40 com- mercial broilers at each of four sites inside, and two sites outside the emission zone. More tissue samples and further rate-of-gain and feed conversion tests followed earlier results, with all chickens apparently enjoying equal health. Two hundred of the broilers were killed and inspected in a poultry processing plant in Calgary, say Paulson and Sawyer, with no rejec- tions and no birds exhibiting dis- ease. The chickens have since been replaced by pigs which arrived a year ago. Now Shell has two boars and eight sows in two pens. Pigs at the emission-zone pen gained weight and converted feed as ef- ficiently as pigs in the clean air pen. say both Shell men. Health watch The most recent additions to Shell's livestock pens are 20 Hereford heifer calves which arriv- ed nine months ago. Like the pigs, they will be watched for general health, tested for weight gain and feed conversion and bred for fertili- ty and genetic consistency.- At each of two sites five yearlings are now given feed grown inside the emission zone. Five are given feed grown outside. All cattle drink the same water. Additional report Page 5 'TREATMENT PLANT WILL REDUCE EMISSIONS' Shell Canada officials are predicting the off-gas treatment plant currently being built at Waterton gas plant will reduce sulphur emissions as well as costly production cutbacks. The Waterton plant, one of the largest sulphur-recovery plants in the world, is permitted by the Energy Resources Conservation Board to emit 248 long tons of sulphur dioxide into the air every day. A long ton weighs pounds. With the permit from ERCB to install the treatment plant (nicknamed SCOT) Shell must reduce the daily emission to a maximum of 80.6 tons. Although Shell's Waterton plant meets current ERCB clean air standards, the plant has its good and its bad days. On a good day, 310 million cubic feet of gas flow through the plant. At the same time, 180 tons of sulphur dioxide goes up the stack. Although 180 tons is well below the permissible level of 248, it's still enough to cause problems. On a bad day, normal emissions are forced down to ground level by high winds or Chinooks. Or a compressor may break down, leaving excess gas to be burned off or "flared.'' Flaring, sometimes a result of human error, produces extra sulphur dioxide, which is recorded by emission monitors. Trailers stationed in areas of high ground level concentration of sulphur dioxide monitor the air, telemetering data into a computer at the plant. The computer interprets the data, and warns the operator of the plant to start cutting back production if the emission levels reach 50 per cent of allowable concentration. Shell officials say the SCOT plant will almost completely recover sulphur, converting it into liquid sulphur which is then or made into dustless chunks, for shipment.