A "cavalier" company boss who killed his childhood friend after sending him into a lake to retrieve golf balls has been jailed for more than two years.
Dale Pike, 25, was supposedly supervising Gareth Pugh, 29, when he entered the water at Peterstone golf club, near Newport, South Wales, to collect golf balls.
Cardiff Crown Court heard that Pike, who had founded Boss Golf Balls with his father Jonathan, was using unsuitable diving equipment, had ignored health and safety guidelines and could not supervise Mr Pugh properly because one of his arms was in plaster.
He was also not qualified to dive either recreationally or commercially and was not trained to supervise others diving.
Pike would pay golf courses 10p for every golf ball he collected and would then sell them online - charging up to £30.99 for a pack of 20 balls.
Mr Pugh, a father-of-one who had the mental age of a nine-year-old when he was 13, worked for Boss Golf Balls on an ad hoc basis, earning up to £40 a day collecting balls.
The incident happened on February 11 last year while Mr Pugh was using diving equipment for the first time, which supplied air from a length of pipe attached to a surface compressor.
Prosecutor Philip Evans QC said: "The defendant was the only other person present and was supposedly acting as the 'banksman' keeping a look out. But that was not effective because he had one of his arms in plaster.
"He realised he had not seen Mr Pugh for some time and the emergency services were called. By the time Mr Pugh had been located he had been submerged for 70 minutes."
Pike had made inquiries with professional diving companies about what he needed to do to collect golf balls safely and was told he would need a qualified team of five people, costing around £1,250 a day, but he only wanted to pay £40 a day.
"There is evidence that the defendant knew of the risks and that this activity was governed by the health and safety regulations. It is clear the defendant knew that the activities he was undertaking were governed by Health and Safety Executive rules and he chose to ignore them," Mr Evans said.
Pike had told prospective employers that he had all the necessary qualifications to run a company retrieving golf balls from ponds and lakes.
A health and safety investigation found there were 16 breaches of regulations, including no risk assessment, Mr Pugh was not qualified to dive, he was not attached to a rope and the equipment he used was not suitable for the job.
"This is a case where many of the failings are stark and many of them were simply matters of basic common sense which this defendant chose to ignore," Mr Evans said.
It is not clear what happened to Mr Pugh but he became detached from his face mask while he was at the bottom of the 2.4 metre deep lake.
His body was found with his bag containing 341 golf bags. The father-of-one had drowned.
At a previous hearing, Pike, of Chain Walk, Glynneath, Neath, admitted a charge of manslaughter by gross negligence.
Davis Elias QC, defending, said: "He has expressed sincere and genuine remorse.
"He does not accept that Gareth Pugh's vulnerability was exploited. He had known him for many years and regarded him as a friend and an equal.
"Dale Pike decided foolishly that the equipment that he purchased was sufficient to enable whoever would use it to go deeper into the lakes.
"He did not believe that this sort of thing would ever be able to happen and he accepts complete responsibility for the failings.
"He naively and foolishly believed all would be well in that lake."
Judge Keith Thomas jailed Pike for 32 months and told him: "You ignored both the risks and advice because it would eat into your profits.
"Instead you sent Mr Pugh into a pond with inadequate equipment, a complete lack of training, and only you as a completely untrained and incapacitated back-up.
"You allowed him to take these risks in order to make a quick buck. I am satisfied that the risk of death or serious injury was obvious to you, and your cavalier attitude to safety was the cause of Mr Pugh's death.
"You ignored all the safety advice for your own personal and financial gain. I accept with hindsight that you bitterly regret what happened and that is reflected in your guilty plea."