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Plight of Hillsborough Bay
waste by about one-third. Formerly for each tonne of kaolin produced, about 8 t granite matrix was quarried, Of the 7 t of residue 0.6 t was micaceous, most of the rest quartz sand which is stacked in enormous glistening white mounds in the neighbourhood. Even so, there will still be a considerable amount of residue to dispose of and not all of it will go underground. Several large mica dams already in use and another for which planning permission has already been obtained, will receive the rest. Providing authorization for these plans is forthcoming from the Planning and River Authorities, English China Clay will stop discharging micaccous wastes into the rivers by 1974, although the St Austell River will still not be clear because of the nature of the land through which it runs. The upshot of all this toing and froing is that the addition of micaceous wastes to the sea by river or pipeline will be avoided at least for the immediate future. This will be of advantage to crab fishermen in the area and no new beaches will receive a deposit of fine white mica waste, although it is doubtful if those in St Austell Bay already contaminated will ever be anything but white because of the natural sediments carried in the rivers, Against this, more land will be inundated to form mica dams and the white mountains of quartz sand will continue to grow. Underground storage of wastes will reduce their rates of growth but not reduce the despoliation of the countryside. Admittedly it is the coast and not the hinterland which is important to the Cornish tourist industry, but it m y be questioned whether the cornpromise plan is not a short-term expedient rather than a solution to this problem of waste disposal. A longer submarine pipeline and dispersion of the waste over a greater area of sea might well have given protection to the beaches and provided a much longer-term solution without detriment to marine resources,
York River Oil
Spill
A spillage of oil from a broken pipeline at the mouth of the York River, Yorktown. Virginia, USA. was reported to the Coastguard at 2315 h on the night of May 5, The break in the pipeline supposedly occurred at about 2150 h. The type of oil involved was Bunker C, a heavy black oil. According to a comment by Lt Wayne Green of the US Coastguard, circulated by the Smithsonian Institution Center for Short Lived Phenomena, on the morning after the spill, Coastguard investigators reported a heavy film of oil that was about 0.8 mm thick, 0.8 km long, and 90 m wide. From this it was estimated that the slick involved about 265,000 1 of oil. The American Oil Co., however, said that, based on what the pipeline contained and what they pumped back out of the pipeline, they thought it was around 38,000 1. The area involved was chiefly that around the mouth of the river. When the spill occurred, the wind was in the SW and W and most of the oil therefore reached the northern shore. Chemical dispersants were used and caused the oil to break up fairly readily. Also, the wind that day was brisk and the seas were choppy which helped to disperse the 0il.- The oil was thick in only two places along the shoreline. Little patches did come ashore and a r'4inbow sheen could be seen on the river, I00
Amoco started pumping the line out immediately and the main spill was stopped by 2200 h. But the oil dripped throughout the night at a rate of perhaps about 2 1 per minute. A boom was put in the water to contain the oil. By May 8, all the oil that remained was a little bit where the two heavy patches had been. There were no reports of any oil-covered birds, but there was some damage to bottom-dwelling organisms as well as to some of the vegetation in the marsh, particularly the swamp grass. These plants will die out, but they will re-sprout because they received a fairly light coating of oil which disappeared fairly quickly.
Plight of Hillsborough Bay Conditions in Hillsborough 'Bay, in the upper part of Tampa Bay, Florida, have been reviewed by Drs Taylor, Hall and Saloman at the Bureau of Commercial Fisheries Biological Laboratory at St Petersburg Beach, Florida. In a report in the Fishery Bulletin of the US Department of Commerce (Vol. 68, No. 2, 191-202, 1971) they analyse the distribution of sediments and benthic molluscs in the bay and conclude that no less than 42% of the area is unhealthy in that it contains no living molluscs. Hillsborough Bay has about 56 km of shoreline and encloses about 10,360 ha of shallow water nearly half of which is 1.8 m or less deep. The tidal range is small and currents are slow. There are extensive deposits of oyster shell which are dredged by the construction industry and considerable parts of the coast have been dredged for fill material or deepened for shipping. Sewage from a population of some 300,000 receives only primary treatment which removes less than half the suspended solids, and 12,000 m~/day of this effluent is discharged into the bay causing considerable enrichment by nitrogen and phosphorus. It is estimated that rivers flowing into the bay add 557 tons a year of phosphorus from natural phosphate deposits in the area and the local phosphate industry also contributes additional phosphates and sediment. This degree of enrichment is responsible for excessive growths of phytoplankton and filamentous algae which in turn cause wide fluctuations in dissolved oxygen, At times the high BOD may reduce oxygen concentration to 1 ml/1 or less near the bottom. The heavy sediment load results in high water turbidity which reduces the growth of marine grasses to a very few stands. Not surprisingly, catches of fish and crustaceans in Hillsborough 'Bay are lower than in any other region of the Tampa Bay complex. So far as molluscs are concerned, no living specimens were found in nineteen of the stations sampled, indicating that 42 per cent of the seabed there was unhealthy. At eighteen stations, classifled as marginal, at least 50 per cent of the indicator species for the bay were present but, on average, these parts of the bay, which comprise 36 per cent of the area, had only about one-fourth the number of species of mollusc and one half the number of individuals as healthy stations near the mouth of the bay. The authors conclude from experience gamed in R afitan Bay and Biscayne Bay that recovery of marginal zones in Hillsborough Bay would be reasonably quick if pollution was abated, but the heavily silted unhealthy areas would probably require a long time to recover.
York River Oil
Spill
A spillage of oil from a broken pipeline at the mouth of the York River, Yorktown. Virginia, USA. was reported to the Coastguard at 2315 h on the night of May 5, The break in the pipeline supposedly occurred at about 2150 h. The type of oil involved was Bunker C, a heavy black oil. According to a comment by Lt Wayne Green of the US Coastguard, circulated by the Smithsonian Institution Center for Short Lived Phenomena, on the morning after the spill, Coastguard investigators reported a heavy film of oil that was about 0.8 mm thick, 0.8 km long, and 90 m wide. From this it was estimated that the slick involved about 265,000 1 of oil. The American Oil Co., however, said that, based on what the pipeline contained and what they pumped back out of the pipeline, they thought it was around 38,000 1. The area involved was chiefly that around the mouth of the river. When the spill occurred, the wind was in the SW and W and most of the oil therefore reached the northern shore. Chemical dispersants were used and caused the oil to break up fairly readily. Also, the wind that day was brisk and the seas were choppy which helped to disperse the 0il.- The oil was thick in only two places along the shoreline. Little patches did come ashore and a r'4inbow sheen could be seen on the river, I00
Amoco started pumping the line out immediately and the main spill was stopped by 2200 h. But the oil dripped throughout the night at a rate of perhaps about 2 1 per minute. A boom was put in the water to contain the oil. By May 8, all the oil that remained was a little bit where the two heavy patches had been. There were no reports of any oil-covered birds, but there was some damage to bottom-dwelling organisms as well as to some of the vegetation in the marsh, particularly the swamp grass. These plants will die out, but they will re-sprout because they received a fairly light coating of oil which disappeared fairly quickly.
Plight of Hillsborough Bay Conditions in Hillsborough 'Bay, in the upper part of Tampa Bay, Florida, have been reviewed by Drs Taylor, Hall and Saloman at the Bureau of Commercial Fisheries Biological Laboratory at St Petersburg Beach, Florida. In a report in the Fishery Bulletin of the US Department of Commerce (Vol. 68, No. 2, 191-202, 1971) they analyse the distribution of sediments and benthic molluscs in the bay and conclude that no less than 42% of the area is unhealthy in that it contains no living molluscs. Hillsborough Bay has about 56 km of shoreline and encloses about 10,360 ha of shallow water nearly half of which is 1.8 m or less deep. The tidal range is small and currents are slow. There are extensive deposits of oyster shell which are dredged by the construction industry and considerable parts of the coast have been dredged for fill material or deepened for shipping. Sewage from a population of some 300,000 receives only primary treatment which removes less than half the suspended solids, and 12,000 m~/day of this effluent is discharged into the bay causing considerable enrichment by nitrogen and phosphorus. It is estimated that rivers flowing into the bay add 557 tons a year of phosphorus from natural phosphate deposits in the area and the local phosphate industry also contributes additional phosphates and sediment. This degree of enrichment is responsible for excessive growths of phytoplankton and filamentous algae which in turn cause wide fluctuations in dissolved oxygen, At times the high BOD may reduce oxygen concentration to 1 ml/1 or less near the bottom. The heavy sediment load results in high water turbidity which reduces the growth of marine grasses to a very few stands. Not surprisingly, catches of fish and crustaceans in Hillsborough 'Bay are lower than in any other region of the Tampa Bay complex. So far as molluscs are concerned, no living specimens were found in nineteen of the stations sampled, indicating that 42 per cent of the seabed there was unhealthy. At eighteen stations, classifled as marginal, at least 50 per cent of the indicator species for the bay were present but, on average, these parts of the bay, which comprise 36 per cent of the area, had only about one-fourth the number of species of mollusc and one half the number of individuals as healthy stations near the mouth of the bay. The authors conclude from experience gamed in R afitan Bay and Biscayne Bay that recovery of marginal zones in Hillsborough Bay would be reasonably quick if pollution was abated, but the heavily silted unhealthy areas would probably require a long time to recover.