Maritime waste treatment firm Nature Group saw shares fall after saying profits would suffer due to its insurance company refusing to pay out on a claim.The firm had claimed £2.45m for damage to property and loss of business following an explosion last May at its waste treatment facility in Gibraltar.The company is appealing the decision but said if it was unsuccessful the group's results would be hit and this would result in an expected profit before tax of approximately £1.5m for the year ended 31 December 2011.Nature added that its current cash reserves were sufficient to deal with the repairs, planned investments and the continuation of the group dividend policy."Whilst this news is disappointing we would like to stress that this is an exceptional situation," the firm said.Investors didn't take kindly to the news, pushing the shares down almost 14% in early trading following the announcement,Nature Group's broker, WH Ireland, was doing what it could on the damage imitation front. "Importantly, a 2,500 tonne chemical tanker for use in the Mediterranean has been acquired, with waste volumes reported to have now returned to the same level as before the incident in Gibraltar," the broker noted. "Demand for the offshore CTUs [compact treatment units] has been strong, with an additional two units currently being built and further opportunities being presented," analyst John Cummins noted.Even WH Ireland acknowledged that the shares are likely to move lower in the short term, but added that it believes "that the investment case and significantgrowth potential for Nature remains particularly attractive."Not surprisingly, the house broker is sticking with its "buy" recommendation, but it has reduced its 12 month share price target to 80p from 95p.